diplomarbeit_cristinafritzsche
The formation of chlorinated
organics during electrolytic urine
treatment
Master thesis of Cristina Fritzsche
August 2012
Supervision: Hanspeter Zöllig and Kai Udert
Professor: Eberhard Morgenroth
The formation of chlorinated organics during electrolytic urine treatment
Plagiats ding
The formation of chlorinated organics during electrolytic urine treatment
Abstract
This master thesis is part of the VUNA project which aims for nutrient recovery and treatment
of urine in decentralized treatment facilities. Electrolysis is used to remove nitrogen through
electrolytic ammonia oxidation. It is a promising treatment option because it is not
susceptible to inflow variations. However, a disadvantage of electrolysis is that chlorinated
organics, which are dangerous for environmental and human health, might be formed.
The overall goal of this master thesis is to analyze the processes of chlorinated organics
formation during electrolytic treatment of stored urine. The subgoals are to choose four
chlorinated, organic substances of interest, to develop a measurement method for these
substances, to quantify the current efficiency in experiments with urine and to either accept
or reject the following hypotheses: 1) Chlorinated organics are formed during the electrolytic
treatment of stored urine. 2) If the electrode potential applied in electrolytic urine treatment is
lower than the potential needed for chloride oxidation, no chlorinated organics are formed.
Through a screening experiment, the following four substances of interest were chosen due
to their high toxicity and abundance: Di-, tri-, tetrachloromethane and chlorobenzene. Since it
was found that a substantial part of these substances moves into in the gas phase, two
identical traps filled with dodecane were added to the electrolysis batch reactor. The gas
evolving from the electrolysis was sucked through the traps with a pump. In recovery
experiments, it was found that almost all of the tetrachloromethane and chlorobenzene, but
only about 40% of the dichloromethane that left the reactor could be recovered in the traps.
The measurement method is subject to a high uncertainty, which is mainly due to the
volatility of the substances.
With voltammetry experiments it was found that when using a graphite electrode ammonia
oxidation started at about 0.5V vs. MSE and chloride oxidation at around 0.9V vs. MSE. With
a graphite anode three urine experiments were conducted: Two at the upper potential (1.3V
vs. MSE), where chlorinated organics were expected, and one at the lower potential (0.8V
vs. MSE), where none were expected. With a boron doped diamond anode, ammonia
oxidation started at about 1.2V vs. MSE and chloride oxidation at about 1.4V vs. MSE. This
means that with a boron doped diamond anode the potential range in which ammonia gets
oxidized but chloride does not is very narrow. Therefore, only one urine experiment where
the formation of chlorinated organics was expected, was conducted at 2V vs. MSE.
Current efficiencies [μg/C] were calculated for chlorobenzene in the urine experiments
because for the other substances the concentrations found were too low. For graphite, the
current efficiencies in the first two experiments with the upper potential were 0.0042 μg/C
and 0.0068 μg/C. In the experiment with the lower potential, the current efficiency was
0.0024 μg/C, and in the experiment with a boron doped diamond it was 0.0035 μg/C.
Ammonia was oxidized in all experiments. For a graphite anode with a lower potential, the
current efficiency for ammonia oxidation was higher (-0.12 μg/C) than with an upper potential
(-0.04 μg/C and -0.06 μg/C).
It can be concluded that the presented measurement method is well applicable for
chlorobenzene and tetrachloromethane, but not for dichloromethane. The trap height could
be increased and the bubble size decreased to improve the diffusive transport from the gas
into the dodecane.
The first hypothesis can be accepted: Chlorinated organics are formed during the electrolysis
of stored urine. The second hypothesis cannot be accepted: Chlorinated organics are also
formed at the lower potential. However, it still is thought to be a good strategy to control the
formation of chlorinated organics by lowering the potential, because the results have shown,
that at a lower potential, less chlorobenzene was formed. In future experiments, the potential
could be stepwise decreased and toxicity measurements could be conducted to find a
potential at which the concentration of the produced chlorinated organics is not harmful.
A substantial part of the chlorinated organics moves to the gas phase. If the formation of
chlorinated organics cannot be prevented during electrolysis of stored urine, the electrolysis
reactor should be built in open air to dilute the chlorinated organics in the atmosphere.
The formation of chlorinated organics during electrolytic urine treatment
Table of Contents
1.
2.
Introduction......................................................................................................................1
1.1.
Context .................................................................................................................... 1
1.2.
Electrolytic oxidation of ammonia and chloride ........................................................ 2
1.3.
The formation of chlorinated byproducts .................................................................. 3
1.4.
Hypothesis and goals .............................................................................................. 5
Methode ............................................................................................................................6
2.1.
3.
Development of the measurement method .............................................................. 6
2.1.1.
Reactor setup ................................................................................................... 6
2.1.2.
Screening experiment ....................................................................................... 7
2.1.3.
Calibration of the GC/MS .................................................................................. 7
2.1.4.
Recovery experiments ...................................................................................... 8
2.1.5.
Model ............................................................................................................... 8
2.2.
Cyclic voltammetry................................................................................................... 8
2.3.
Urine experiments.................................................................................................... 9
Results and discussion ................................................................................................. 10
3.1.
Development of a measurement method ............................................................... 10
3.1.1.
Substances ..................................................................................................... 10
3.1.2.
Recovery experiments .................................................................................... 11
3.1.3.
Uncertainties................................................................................................... 17
3.1.4.
Model of the recovery experiments ................................................................. 18
3.1.5.
Summary ........................................................................................................ 18
3.2.
Cyclic voltammetry experiments ............................................................................ 19
3.2.1.
Graphite.......................................................................................................... 19
3.2.2.
Boron doped diamond .................................................................................... 20
3.3.
Urine experiments.................................................................................................. 21
3.3.1.
Graphite.......................................................................................................... 22
3.3.2.
Boron doped diamond .................................................................................... 25
3.3.3.
Concentrations in the gas leaving the system ................................................. 25
3.3.4.
Nitrogen and COD degradation ...................................................................... 26
3.3.5.
Comparison of the graphite and the boron doped diamond electrode ............. 26
4.
Conclusion and outlook ................................................................................................ 27
5.
Acknowledgements ....................................................................................................... 29
6.
References ..................................................................................................................... 30
Cover picture: Photo and schema by Cristina Fritzsche. Graph: GC/MS analysis of a sample
from the screening experiment.
i
The formation of chlorinated organics during electrolytic urine treatment
Table of figures
Figure 1: Two possible process schemes to recover nutrients from urine: Evaporation and
Precipitation, with electrolysis as part of the process combinations (Source: Udert, 2010.
Changes by Hanspeter Zöllig). ............................................................................................... 1
Figure 2: Simplified schema of the process of electrolytic urine treatment. Desired reaction:
Ammonia oxidation. Undesired reaction: Formation of chlorinated organics. ......................... 3
Figure 3: Schema of the experiment process. Squares: experiments / process steps. Italic:
Goals of the process steps..................................................................................................... 6
Figure 4: Experiment setup for the screening experiment, the recovery experiments and the
urine experiments. The gas from the potentiostatic experiments is sucked through two traps
filled with dodecane to trap chlorinated organics. The gas flow is controlled with a valve and
measured with a gasmeter. The reactor is mixed with a magnetic stirrer. .............................. 7
Figure 5: Experiment Blank_1. Concentration of chlorinated organics at three different
places in the system changing with time. 2.4mg of chlorinated organics spiked into a reactor
of 300ml 1M NaClO4 solution. Applied current density: 5mA/m2. Evolving gas sucked through
two traps of 10ml dodecane each (gas flow: 1.24l/h). Data points with orange box:
concentration higher than calibration area. .......................................................................... 11
Figure 6: Experiment Blank_2. Concentration of chlorinated organics at three different
places in the system changing with time. 1.2mg of chlorinated organics spiked into a reactor
of 300ml 1M NaClO4 solution. Applied current density: 5mA/m2. Evolving gas sucked through
two traps of 12ml dodecane each (7.12l/h). Data points with orange box: Concentration
higher than calibration area.................................................................................................. 12
Figure 7: Experiment Air_2. Concentrations of chlorinated organics at three different places
in the system changing with time. 1.2mg/l of chlorinated organics spiked into a reactor of
300ml distilled water. No current applied, turbulence generated with a high turbulence
magnetic stirrer. Evolving gas sucked through two traps of 82ml dodecane each (1.04l/h).
Data points with orange box: Concentration higher than calibration range. .......................... 13
Figure 8: Experiment Blank_4. Concentrations of chlorinated organics at three different
places in the system changing with time. 1.2mg of chlorinated organics spiked into a reactor
of 300ml 1M NaClO4 solution. Applied current density: 5mA/m2. Evolving gas sucked through
two traps of 82ml dodecane each (1.74l/h). Data points with orange / grey box: Concentration
higher / lower than calibration range. ................................................................................... 14
Figure 9: Mass balance. Mass found in reactor, trap 1 and trap 2 respectively, divided by the
mass maximally found in the reactor. Reactor of 300ml 1M NaClO4 solution. Applied current
density: 5mA/m2. Evolving gas sucked through two traps of 82ml dodecane each. Gray data:
Low concentration with high uncertainty, assumed zero. Pink square: Everything that leaves
the reactor is expected to end up in the first trap.................................................................. 15
Figure 10: Uncertainties of the measurement method for the analysis of chlorinated .......... 17
Figure 11: Cyclic voltammetry experiment with a graphite electrode, a graphite counter
electrode and a MSE reference electrode. Scan rate: 200mV/s, scan from -1.3V to 1.4V. For
all four experiments the 1st cycle of five cycles is shown. Red lines: Upper and lower
potential, chosen for urine experiment with and without formation of chlorinated organics. .. 19
ii
The formation of chlorinated organics during electrolytic urine treatment
Figure 12: Cyclic voltammetry experiment with a boron doped diamond electrode, a platinum
wire as a counter electrode and a MSE reference electrode. Scan rate: 200mV/s, scan from 2’300mV to 2’200mV. For all four experiments the 1st cycle of five cycles is shown. Red line:
Potential, chosen for the urine experiment, production of chlorinated organics is expected. 20
Figure 13: Production of chlorinated organics during electrolytic treatment of urine. Boron
doped diamond anode and graphite cathode. Applied potential: 2V vs. MSE. 300ml of stored
urine. Evolving gas sucked through two traps of 20ml dodecane each (gas flow: 1.74l/h).
Data points with orange box: Concentration higher than calibration area. ............................ 25
Table of tables
Table 1: Literature values for the potentials for H2 and O2 evolution and the oxidation of NH3
and Cl-. .................................................................................................................................. 9
Table 2: Characteristics of the chlorinated organics of interest. Values at 25°C (Sources: 1),
3), 4), 10) Schwarzenbach, 2003, 2) Frenkel, 2002, 6) Hand, 2003; Bullister, 1998, 7) Xie,
1994, 8) Abraham, 1994, 10) US EPA, 2012, 11) Anderson, 1957; Hansen, 1967). ............ 11
Table 3: Risks for human health and for the environment (Source: EU regulations). ........... 11
Table 4: Experiment set up and parameters for the electrolytic treatment of urine. Gas
evolving from electrolysis sucked through two traps filled with dodecane. Italic: Controlled
parameters. Eup = upper potential: formation of chlorinated organics expected. Elow = lower
potential: No formation expected. Index G = graphite, index BDD = boron doped diamond. 21
Table 5: Current efficiencies of the formation of chlorinated organics in electrolytic treatment
of stored urine with graphite electrodes. Potentials applied: Eup_G1 and Eup_G2: 1.3V vs.
MSE. Elow_0.8V vs. MSE. Eup = upper potential: Formation of chlorinated organics
expected. Elow = lower potential: No formation expected. Gray background: Concentrations
too low to calculate efficiencies. Yellow background: Current efficiencies for comparison. ... 22
Table 6: Chloride degradation and formation of chlorine in electrolytic treatment of stored
urine. Potentials applied: Eup_G1 and Eup_G2: 1.3V vs. MSE. Elow_G1: 0.8V vs. MSE. G =
graphite electrode, BDD = boron doped diamond electrode. ................................................ 23
Table 7: Removal of nitrogen and COD / Production of nitrate and nitrite in 4 experiments for
potentiostatic electrolytic treatment of stored urine. G = graphite anode, BDD = boron doped
diamond electrode. Applied potentials: Eup_G1 and Eup_G2: 1.3V vs. MSE. Elow_G1: 0.8V
vs. MSE. Eup_BDD1: 2V vs. MSE. Total nitrogen = ammonia + nitrite + nitrate. .................. 26
iii
The formation of chlorinated organics during electrolytic urine treatment
1. Introduction
1.1.
Context
This master thesis is part of the VUNA project, which aims for nutrient recovery and
treatment of urine in decentralized water treatment facilities. There are different process
combinations to reach this goal and electrolysis is one of the treatment steps (figure 1).
Figure 1: Two possible process schemes to recover nutrients from urine: Evaporation and Precipitation,
with electrolysis as part of the process combinations (Source: Udert, 2010. Changes by Hanspeter Zöllig).
Ammonia oxidation is the main goal of the electrolytic urine treatment in the VUNA project.
Ammonia can either be completely oxidized to elementary nitrogen to remove it from the
solution, or it can be partially oxidized to ammonium nitrate or nitrate, which can then be
used as a fertilizer.
For several reasons, chemical oxidation is an attractive alternative to the biological oxidation:
The treatment is highly efficient, persistent organic compounds also get removed and there is
no need for chemicals, as current is the only process input (Anglada et al., 2009). An
additional advantage which is important in the VUNA project is that in contrast to a biological
treatment, an electrolytic treatment is not susceptible to irregular inflow conditions (Eawag,
2010). It can therefore be used in decentralized application where inflows are irregular and
sometimes no urine is discharged over a long time period. The disadvantages of electrolysis
are the high energy consumption and the formation of chlorinated organics, which can
endanger the environment and human health.
If electrolysis is used as a treatment step in the VUNA project, toxic effluents might therefore
be produced. With this context in mind, the goal of this master thesis is to achieve a better
understanding of the formation of chlorinated organics during electrolytic treatment of source
separated urine and to suggest how this formation could be prevented. To define specific sub
goals, the processes that lead to the formation of chlorinated organics and the parameters
influencing this formation have to be identified.
1
The formation of chlorinated organics during electrolytic urine treatment
1.2.
Electrolytic oxidation of ammonia and chloride
Electrolysis is a chemical process that can be used to remove pollutants from a conducting
liquid phase. By applying a voltage to a electrolysis cell, a current is flowing between anode
and cathode and thereby pollutants can be oxidized and reduced. For a certain reaction to
happen, a certain potential is needed. This consist of the thermodynamically necessary
potential (E°) plus the overpotential which depends on the electrode material and the
electrolyte.
There are different ways of electrolytic oxidation:
1. In direct oxidation, the pollutant is adsorbed to the surface of the electrode and loses
electrons through interactions only with the electrode surface (Panizza et al., 2009).
2. When the applied potential is high enough, intermediates of the oxygen evolution
reaction (e.g. hydroxyl radicals) can oxidize pollutants. (Panizza et al., 2009).
3. In indirect electrolysis, the oxidation takes place in the bulk phase or at the electrode and
is mediated through a compound electrolyticly built directly at the electrode or in its
vicinity (Panizza et al., 2009).
The type of oxidation that is favored is assumed beside others to depend on the compound
to be removed, on the electrode, on the applied potential and on the composition of the
electrolyte.
Ammonia oxidation
Electrolysis has been used for nitrogen, phosphorus and organic compound removal in urine
(Ikematsu et al., 2006; Ikematsu et al., 2007) and for ammonia oxidation (de Vooys et al.,
2001; Kapalka et al., 2010a; Kapalka et al., 2010b; Kapalka et al., 2011). In electrolytic
treatment of fresh urine urea is first degraded to ammonia which is then oxidized to nitrite or
nitrogen gas (Ikematsu et al., 2006).
Ammonia can be oxidized in different ways. When platin based electrodes are used,
ammonia is mainly directly oxidized (simplified from de Vooys et al., 2001):
NH3,ads  NH2,ads + H+ + eNH2,ads  NHads + H+ + eNHads + NHads  N2 + H+ + eWith metal oxide electrodes, the oxidation process of ammonia is less understood, but it is
known that ammonia is oxidized through several steps to various nitrogen compounds
(Kapalka et al., 2011). Ammonia can also get oxidized indirectly with chloride (Vlyssides et
al., 1997; Li et al., 2009). Kapalka et al. (2010b) stated that ammonia can get efficiently
removed from acidic solution by chlorine.
In figure 2, the possible ways of ammonia oxidation are shown schematically.
Chlorine
Active chlorine species are mediator compounds, which can be used to indirectly oxidize
various pollutants. The oxidation of the pollutant can either take place at the anode (through
oxochloro species generated by the interaction of the chloride with the electrode surface) or
in the bulk solution through oxidants as chlorine, hypochlorous acid or hypochlorite. These
oxidants are produced by the oxidation of chloride ions (Panizza et al., 2009):
2
The formation of chlorinated organics during electrolytic urine treatment
2Cl-  Cl2 + 2eCl2 + H2O  HOCl + H+ + ClHOCl  H+ + OClIn figure 2, the oxidation of chloride is shown schematically.
1.3.
The formation of chlorinated byproducts
The explicit electrolytic reactions for the oxidation of organic compounds with active chlorine
and the formation of chlorinated organics are complex and not fully understood (Panizza et
al., 2009). It is assumed that chlorinated organics are the product of a reaction between
active chlorine, which is the result of oxidized chloride ions, and organic compounds. In
urine, organic compounds and chloride ions are present (appendix 1; Putnam et al., 1971),
so the formation of chlorinated organics during electrolysis is possible. In figure 2, a
simplified schema of the process of electrolytic treatment of stored urine is shown. In stored
urine, most of the nitrogen is present as ammonia (appendix 1; Laureni et al., 2012).
Ammonia can be oxidized directly or indirectly. The reaction for the formation of chlorinated
organics can either happen at the electrode or in the bulk phase. It is not known which
organic substance is the source of the carbon of chlorinated organics. In stored urine, almost
50% of the carbon is present as acetate (appendix 1.1; Geigy, 1977). When a graphite anode
is used, there is an additional potential source for carbon: Graphite is known to corrode when
used as an anode in electrolysis (Panizza et al., 2009). It is possible that carbon species
from the corroded graphite react with the active chlorine and build chlorinated organics.
Figure 2: Simplified schema of the process of electrolytic urine treatment. Desired reaction: Ammonia
oxidation. Undesired reaction: Formation of chlorinated organics.
The formation of chlorinated organics in electrolytic treatment has been studied by a few
researchers (Bonfatti et al., 2000b; Anglada et al., 2010; Lei et al., 2007), but the main
interest lies in the research about the oxidative power of chlorine and the indirect oxidation of
organics by active chlorine.
It is assumed that the factors influencing the electrolytic oxidation of organic compounds in
the presence of chlorine also influence the formation of chlorinated organics. According to
Panizza et al. (2009) and Anglada et al. (2010) the following factors are important:
3
The formation of chlorinated organics during electrolytic urine treatment
•
•
•
•
•
•
•
Electrode material
Potential / current density
Treatment time
Chloride concentration
Solution temperature
pH
Concentration and type of organic compounds
Electrode material
Electrodes are the catalysts of the electrolytic oxidation, they either take up or give away
electrons. As explained in chapter 1.2, the electrode material has an influence on how the
reaction takes place (e.g. direct or indirect).
Potential / current density
The type of reactions that occur during electrolytic treatment can be influenced by the
potential that is applied. The potentials needed for a certain reaction are thought to depend
beside others on the compounds, the electrolyte and the electrode. Reactions can therefore
be triggered or prevented by changing the electrode potential. Anglada et al. (2010) stated
that the formation of trihalomethanes (e.g. chloroform) increases with increasing current
density.
Chloride concentration
The oxidative power of chlorine has been confirmed by different researchers. Kapalka et al.
(2010b) stated that electrolytic oxidation mediated with chlorine has especially gained
attention in waste water treatment because of its abundant occurrence. They found that
ammonia can be efficiently removed in electrolysis with active chlorine. Bonfatti et al. (2000a)
found that glucose oxidation on a Ti/Pt electrode in an alkaline electrolyte is faster at higher
chloride concentrations. Panizza et al. (2009) stated that the presence of chloride also
inhibits the oxygen formation and therefore higher potentials can be applied in the
electrolysis, which means that the oxychloro radicals have a higher oxidative efficiency.
Czarnetzki et al. (1991) also found that in the electrolysis of NaCl the current efficiency for
hypochlorite increases and the current efficiency of chlorate and oxygen decrease with
increasing NaCl concentration. This means that the process of active chlorine production
gets more efficient at a higher chloride concentration.
Concentration and type of organic compounds
There are different compounds present in fresh, stored and processed urine and therefore
also the amount of formed chlorinated organics might differ. In fresh urine, there is a lot of
different COD species present, and in stored urine almost 50% of the COD is acetate
(appendix 1.1). Bonfatti et al. (2000b) didn’t find any chlorinated organics in an electrolytically
treated glucose and chloride solution, but Anglada et al. (2010) found chlorinated organics in
electrolytically treated urine. One reason for that could be the different organic compounds
present.
4
The formation of chlorinated organics during electrolytic urine treatment
pH, temperature and treatment time
The pH has an influence on the chloro and organic species present in the solution. At a lower
pH the formation of ineffective chloro species (chlorate and perchlorate) can be reduced
(Kapalka et al. 2010b). This is reconfirmed by Amstutz et al. (2012). During electrolytic
oxidation of glucose the pH decreases (Bonfatti, 2000b). Bonfatti et al. (2000a) found that
with increasing pH the reaction rate for the oxidation of organics increases.
Bonfatti et al. (2000a and 2000b) found that the electrolytic oxidation of glucose in a chloride
containing solution gets faster when the temperature is decreased. One reason for this could
be the decrease of the oxygen evolution rate at a lower temperature. Another reason could
be the decrease of chlorate formation. This is consistent with the findings of Kapalka et al.
(2010b), who stated that a high temperature favors chlorate formation.
In electrolytic treatment of mine leachate with a BDD electrode, Anglada at al. (1010) found
that the formation of chlorinated organics increases with treatment time for thrihalomethane
(e.g. chloroform), haloacetonitriles and haloketones and decreases for 1,2-dichloroethane
(Anglada et al., 2010; using a BDD electrode).
1.4.
Hypothesis and goals
To provide a nontoxic effluent after electrolytic urine treatment, the formation of chlorinated
organics can either be prevented or an additional treatment step is necessary. Since an
additional treatment step makes the overall treatment more complicated, this thesis aims at
preventing the formation of chlorinated organics during electrolysis. Substances of interest
are chosen to be measured as an indicator for the formed chlorinated organics.
To prevent the formation of chlorinated organics, either the presence of active chlorine or of
the organic compounds has to be prevented. To provide an electrolyte totally free of organics
is not easily possible. Active chlorine on the other hand is not present in the influent, it
evolves during electrolysis. It is therefore possible to prevent the active chlorine formation
during electrolysis by changing the operation parameters.
The electrode material and the potential are considered to be the most important parameters
for the formation of chlorinated organics. These parameters can be changed and adjusted
easily and therefore in this thesis the influence of these parameters on the formation of
chlorinated organics is analyzed.
The following hypotheses are stated:
1. Chlorinated organics are formed during the electrolytic treatment of urine.
2. If the electrode potential applied in electrolytic urine treatment is lower than the
potential needed for chloride oxidation, no chlorinated organics are formed.
At the end of this master thesis:
•
•
•
•
The substances of interest are chosen.
A measurement method is developed for the substances of interest.
The current efficiency of chlorinated organic production is quantified.
The hypotheses are either accepted or rejected.
5
The formation of chlorinated organics during electrolytic urine treatment
2. Methode
2.1.
Development of the measurement method
A measurement method was developed to quantify the amount of chlorinated organics that
are produced during electrolytic treatment of urine. In figure 3, the schema of the experiment
procedure of this master thesis project is shown. In the preceding chapters, each experiment
or process step will be described. For the experiments with urine, stored urine was used. The
characteristics and names of all experiments can be seen in appendix 2.
Figure 3: Schema of the experiment process. Squares: experiments / process steps. Italic: Goals of the
process steps.
2.1.1. Reactor setup
In the screening experiments it was found that there was also a substantial amount of
chlorinated organics present in the gas phase and not only in the liquid phase of the reactor.
It was concluded that the chlorinated organics are stripped out of the reactor with the gas
evolving from the electrolysis (e.g. H2, O2 and Cl2). Therefore, the gas was sucked out of the
reactor (reactor volume 300ml) and the substances were trapped in two dodecane traps
(volume 10ml, 12ml, 20ml and 82ml, depending on the experiment), which were then
sampled and analyzed with GC/MS (see figure 4 for the reactor setup). The gas flow was
controlled with a valve and not changed during the experiment. The reactor was mixed with a
magnetic stirrer.
Samples were taken from three sections of the system: From the reactor, from trap 1 and
from trap 2. The samples from the reactor were extracted with dodecane, the samples from
the traps diluted if necessary or directly analyzed.
6
The formation of chlorinated organics during electrolytic urine treatment
Figure 4: Experiment setup for the screening experiment, the recovery experiments and the urine
experiments. The gas from the potentiostatic experiments is sucked through two traps filled with dodecane to
trap chlorinated organics. The gas flow is controlled with a valve and measured with a gasmeter. The reactor is
mixed with a magnetic stirrer.
The temperature was controlled at 25°C. The pH was monitored but not controlled.
geometrical surface area of the anode and cathode was 20cm2. The current density
calculated using this geometrical surface area. Either a Ag/AgCl or an MSE electrode
used as a reference electrode, depending on the experiment. The instantaneous flow
measured with a bubble meter and the integrated flow with a gas meter.
The
was
was
was
2.1.2. Screening experiment
A potentiostatic screening experiment was conducted to find out what substances are
present in electrolyzed stored urine. The applied potential was 1.5V vs. Ag/AgCl (= 0.86V vs.
MSE), a graphite anode and cathode were used and the experiment was run for 24 hours.
The gas evolving from the electrolysis was traped with two traps filled with 3ml dodecane in
the first and 2ml in the second trap. The evolving gas from electrolysis was pushed through
the traps by its own pressure. The results of the screening experiment can be seen in
appendix 3.
2.1.3. Calibration of the GC/MS
GC/MS is an analysis method which combines gas chromatography and mass spectrometry.
To quantify the peaks of the GC/MS analysis, a series of calibration solutions was
developed. After multiple series it was found that the optimum analysis range in GC/MS for
the substances of interest is from 0.2mg/l to 1.5mg/l. Four calibration solutions with the
concentrations 0.2mg/l, 0.6mg/l, 1mg/l and 1.5mg/l were developed. The procedure of the
calibration solutions production is shown in appendix 4. The calibration solutions were
renewed at least every two weeks. The samples from the recovery and urine experiments
had to be diluted to reach a concentration that was in the range between 0.2mg/l and
7
The formation of chlorinated organics during electrolytic urine treatment
1.5mg/l. If the concentration of a sample was not in the calibration range, it was assumed to
have a higher uncertainty than a sample with a concentration within the calibration range
(see chapter 3.1.3).
2.1.4. Recovery experiments
The recovery experiments were conducted to quantify how much of the mass spiked into the
reactor can be recovered in the traps and how much is lost with the gas leaving the system.
A known mass of chlorinated organics was therefore spiked into the reactor. Samples were
taken periodically and at three different sections in the system (reactor, trap 1 and trap 2) to
quantify how much can be found where depending on the time.
Blank electrolyte with spiked chlorinated organics (“Blank experiments”)
An inert electrolyte (1M NaClO4) was spiked with a known mass (experiment Blank_1:
2.4mg; all other experiments: 1.2mg) of chlorinated organics. The cell was operated
galvanostatically with a current density of 5mA/m2. Two graphite plates served as anode and
cathode. An Ag/AgCl-electrode in a luggin tip filled with 3M KCl was used as the reference
electrode. In experiment Blank_1, the dodecane volume in each trap was 10ml. In Blank_2 it
was 12ml and in Blank_4 it was 82ml. Blank_3 had to be aborted because the traps were
broken.
Distillated water with spiked chlorinated organics (“Air experiments”)
It could not be excluded that the chlorinated organics get reduced at the cathode during the
electrolysis. For an additional experiment series, the reactor only contained distilled water
and was not electrolyzed. The transport into the traps was only triggered by the sucking
pump and the turbulence in the reactor.
2.1.5. Model
In the recovery experiments it was found that the chlorinated organics cannot be hold in the
traps forever but get stripped out again. To predict the time period where the substances are
still held in the reactor, a model was developed for the system. Berkeley Madonna, a
differential equation solver, was used to develop the model (Macey et al., 2001).
2.2.
Cyclic voltammetry
To determine the potentials needed for chloride oxidation and ammonia oxidation, cyclic
voltammetry experiments were conducted for all three available electrodes (graphite, boron
doped diamond and iridium dioxide). In cyclic voltammetry, the electrode potential is changed
and the resulting current is measured. A positive peak in the voltammogram indicates a
substance getting oxidized and a negative peak indicates a substance getting reduced. The
geometrical surface area of the working electrode was 0.5cm2. Either a graphite stick (area
2.58cm2 for V_G1, V_G2 and V_G3) or a platin wire (area 1.26cm2 for all other experiments)
was used as a counter electrode. A MSE electrode in a luggin tip with saturated K2SO4 was
used as a reference electrode. The area of the counter electrode was chosen at least 2.5
bigger than the working electrode so it could be excluded that the area of counter electrode
limits the current. The electrodes were rubbed with a dry tissue after every experiment and
cleaned by rinsing them with ethanol and distilled water.
The upper potential was changed stepwise in the borders of oxygen and hydrogen evolution.
These borders were found in the literature (table 1). The first experiment was conducted in
8
The formation of chlorinated organics during electrolytic urine treatment
supporting electrolyte (1M NaClO4), the second in a chloride containing solution (0.085M
NaCl and 1M NaClO4), the third in an ammonia containing solution (0.25M NH4ClO4 and 1M
NaClO4) and the last in a solution containing both chloride and ammonia (0.085M NaCl,
0.25M NH4ClO4 and 1M NaClO4). The working electrode was cleaned after each experiment
by cyclic voltammetry in supporting electrolyte (1M NaClO4). To show that the results are
reproducible, the potential was changed in five cycles in every experiment.
In the beginning of each experiment, the pH was adjusted to 9 to simulate the pH of urine
and to guarantee the presence of ammonia, which is getting oxidized more easily than
ammonium. During the electrolysis, the electrolyte was not stirred. The reactor was purged
with argon to remove oxygen from the solution. With ammonia in the solution, Argon bubbling
was done only once before the pH adjustment in the beginning of an experiment series to
prevent NH3 stripping.
-
Table 1: Literature values for the potentials for H2 and O2 evolution and the oxidation of NH3 and Cl .
Potential: [V] vs MSE
Graphite
Iridium dioxide
Boron-doped diamond
2.3.
H2 evolution O2 evolution NH3 oxidation Cl - oxidation
starts at
starts at
peaks at
starts at
-2.2
1.4
0.9
1
-1.3
0.9
0.5
0.7
-2.3
2.2
1.6
Source
Zöllig 2011, unpublished
Kapalka 2010a, 2011
Kapalka 2010b
Urine experiments
For the urine experiments, stored male urine was used. See appendix 1 for the constituents.
The following experiments were planned to test the hypotheses:
It was planned to conduct two experiments for each electrode:
•
•
Upper potential: The upper potential is chosen high enough so that chloride gets
oxidized and active chlorine evolves. Formation of chlorinated organics is expected.
Lower Potential: The lower potential is chosen low enough so that no chloride
oxidizes and therefore no active chlorine evolves. However, the potential is still
chosen high enough so that ammonia can be oxidized.
Samples were taken periodically to analyze the influence of the treatment time and to gain a
better insight into the kinetics of the formation of chlorinated organics. With the results from
the recovery experiment (experiment Blank_4), the concentration in the gas leaving the
system could be calculated.
Beside the samplse for the analysis chlorinated organics, samples for ion chromatography
analysis were taken from the reactor: Ammonia, nitrogen and chloride were measured. COD
(chemical oxygen demand = sum parameter for organic substances) was analyzed using Dr.
Lange tests. COD measurements only make sense when another electrode than graphite is
used because the corroded graphite falsifies the COD measurements.
9
The formation of chlorinated organics during electrolytic urine treatment
3. Results and discussion
3.1.
Development of a measurement method
3.1.1. Substances
To choose certain substances, that will be analyzed and quantified during this master thesis,
relevant substances found in the literature were compared with substances found in the
screening experiment.
Polkowska et al. (2003) analyzed untreated urine and drinking water samples in Poland and
mainly found di- and trichloromethane (chloroform). The concentration in the drinking water
samples was in the μg/l range, in the urine samples it was about one order of magnitude
lower. There were different chlorinated organic substances found in electrolyticly treated
liquids: Anglada et al. (2011) electrolyticly treated landfill leachate and analyzed the evolution
of different halogenated organics. In treated liquid samples they mainly found
trihalomethanes (chloroform, bromdichloromethane, bromoform) in the mg/l range. Lei at al.
(2007) also analyzed electrolyticly treated leachate, which was pretreated in a bioreactor.
Among others they found chloropentyne, trichloropropane, and dichloropropanol. Richardson
et al. (2010) analyzed air and water samples in swimming pools and mainly found
chloroform, bromdichloromethane and dibromchloromethane. Herbert et al. (2010) reviewed
data of emerging disinfection byproducts and prioritized them concerning toxicity,
occurrence, epidemiology and availability of guidelines. Beside others they selected di- and
tetrachloromethane, nitrosamines, chlorate, and formaldehyde as the most critical
unregulated emerging disinfection byproduct.
In the screening experiment samples were taken from from dodecane traps (where the gas
evolving from the electrolytic treatment of urine was trapped) and analyzed with GC/MS. The
following compounds were found: Trichloromethane (chloroform), chloromethane,
dicloromethane, tetrachloromethane, cyanogenchloride, bromomethane, chloropropene,
dichloropropene, dimethylsulfide, and chlorobenzene. For the GC/MS analysis picture see
appendix 3.
Considering the above findings, the following compounds are chosen to be analyzed and
quantified:
• Dichloromethane
• Tetrachloromethane
• Trichloromethane (Chloroform)
• Chlorobenzene
For information about these substances in table 2 the chemical characteristics and in table 3
the risks for human health and the environment are listed. Since no partition coefficient was
found for dodecane, which was chosen to be the trapping agent in this thesis, the partition
coefficient for hexadecane was used as an approximation. The partition coefficient in this
thesis therefore always refers to the partition coefficient of a chlorinated organic substance in
hexadecane.
10
The formation of chlorinated organics during electrolytic urine treatment
Table 2: Characteristics of the chlorinated organics of interest. Values at 25°C (Sources: 1), 3), 4), 10)
Schwarzenbach, 2003, 2) Frenkel, 2002, 6) Hand, 2003; Bullister, 1998, 7) Xie, 1994, 8) Abraham, 1994, 10) US
EPA, 2012, 11) Anderson, 1957; Hansen, 1967).
Molar Mass
Density
Vapor pressure
Henry coefficient
Saturation concentration in water
Henry coefficient in 1M NaCl solution
Saturation concentration in 1M NaCl solution
Partition coefficientin hexadecane
Saturation concentration in hexadecane
Diffusion coefficient in water
Diffusion coefficient in actetone
Unit
Dichloromethane Trichloromethane Tetrachloromethane Chlorobenzene Source
[g/mol]
84.93
119.38
153.82
112.56
1)
[kg/m3]
1316
1479
1584
1101
2)
[Pa]
57'544
25'119
14'454
1'585
3)
[-]
0.11
0.15
1.10
0.15
4)
[g/l]
18.4
8.0
0.8
0.5
5)
[-]
0.14
0.21
1.36
0.24
6)
[g/l]
14.4
5.8
0.7
0.3
7)
[-]
0.0096
0.0033
0.0015
0.0002
8)
[g/l]
206
365
597
327
9)
[cm2/s]
1.50E-05
8.80E-06
8.70E-06
10)
[cm2/s]
3.60E-05
3.54E-05
8.96E-06
11)
Table 3: Risks for human health and for the environment (Source: EU regulations).
Dichloromethane
-suspected of causing cancer
Trichloromethane
-may cause skin iritation
-may cause organ damages
-suspected of causing cancer
Tetrachloromethane
-toxic if inhaled, in contact with skin
-toxic if swallowed
-may cause organ damages
-suspected of causing cancer
-dangerous to the ozone layer
-harmful to aquatic life
Chlorobenzene
-harmful if inhaled
-toxic to aquatic life
-flamable in liquid and vapor
3.1.2. Recovery experiments
The data for the recovery experiments can be seen in appendix 5.
Blank electrolyte spiked with chlorinated organics and a trap volume of 10ml
(experiment Blank_1) and 12 ml (experiment Blank_2)
Figure 5: Experiment Blank_1. Concentration of chlorinated organics at three different places in the
system changing with time. 2.4mg of chlorinated organics spiked into a reactor of 300ml 1M NaClO4 solution.
2
Applied current density: 5mA/m . Evolving gas sucked through two traps of 10ml dodecane each (gas flow:
1.24l/h). Data points with orange box: concentration higher than calibration area.
11
The formation of chlorinated organics during electrolytic urine treatment
In figure 5 it can be seen that the movement of the substances through the system is in
accordance with their characteristics: Tetrachloromethane, which is the least soluble in water
(H = 1.10), got removed out of the reactor first and therefore entered the trap first.
Dichloromethane which is the best soluble in water (H = 0.11) was removed out of the
reactor the slowest. Chlorobenzene, which has the lowest partition coefficient (L = 0.0002)
stayed in the traps the longest. Dichloromethane, with a partition coefficient almost 50 times
higher than the one of chlorobenzene (L = 0.0096), could not be hold in the trap for long.
Not all the mass that should have been spiked in could be found in the reactor in the
beginning of the experiment. This was expected since the process of spiking is subject to a
high uncertainty due to the volatility of the substances (see chapter 3.1.3). Additionally, it is
possible that parts of the substances that were in the reactor right in the beginning were
already stripped and moved into the gas phase before the first measurement was taken. The
concentration of the spiking solution was above the saturation concentration of the
substances. This led to a two phased spiking solution. However, the comparison of the
substances shows that the most soluble compound (dichloromethane) was recovered better
than the least soluble compound (tetrachloromethane).
The data points marked with orange squares might lie out of the linear relationship between
the area discovered in the GC/MS analysis and the calculated concentration. Therefore, they
are considered to have a high uncertainty (see chapter 3.1.3).
Based on the results of experiment Blank_1, it was expected that in the beginning of the
experiment there is a period where most of the spiked mass is still in the system and so it
should be possible to close the mass balance. Therefore, for the next experiment Blank_2
more samples were taken in a shorter experiment time. The trap volume was slightly
increased to hold back more of the substance, by increasing the trap height. The amount
spiked into the reactor was decreased from 2.4mg to 1.2mg to decrease the concentration in
the spiking solution.
Figure 6: Experiment Blank_2. Concentration of chlorinated organics at three different places in the
system changing with time. 1.2mg of chlorinated organics spiked into a reactor of 300ml 1M NaClO4 solution.
2
Applied current density: 5mA/m . Evolving gas sucked through two traps of 12ml dodecane each (7.12l/h). Data
points with orange box: Concentration higher than calibration area.
The concentrations measured in experiment Blank_2 (figure 6) are consistent with the
characteristics of the particular substances. There must have been a spiking error since the
mass of chlorobenzene exceeded the mass that should have been spiked in by a factor of up
12
The formation of chlorinated organics during electrolytic urine treatment
to 6. This could be due to the fact that the concentration of the spiking solution was still
slightly above the saturation concentration of chlorobenzene. It is possible that the volume of
the spiking solution that was spiked into the reactor contained a phase of pure
chlorobenzene, which then led to a much higher concentration in the reactor. Another option
is that a part of the chlorobenzene got absorbed to the anode in experiment Blank_1 and
desorbed again in experiment Blank_2. But the concentration found in Blank_2 in the reactor
was much bigger than the one found in Blank_1, so the option of absorbance is relatively
unlikely. Dichloromethane got hold back in the reactor and did not decrease until after five
hours.
The gas flow had to be increased for experiment Blank_2 because at a lower flow, no
bubbles could be detected in the traps. This is an indication for leaks in the system. It was
observed that the movement through the traps was much faster in Blank_2 than in Blank_1,
which could be a reason the fact that the peaks found in Blank_2 were for most substances
further away from the expected concentration than in the first experiment.
Based on the low recovery it was decided to optimize the system: Higher and bigger traps
(32cm instead of 28cm, 82ml instead of 10ml), which produce smaller bubbles at a lower flow
rate were used. The connection pipes were sealed with silicone. Since the chlorinated
organics might get reduced in the electrolysis, the transport process out of the reactor was
simulated only by high turbulence. The spiking solution was further diluted.
Distilled water spiked with chlorinated organics (experiments Air_1 and Air_2)
Due to the new system conditions (bigger trap, different process to remove substances out of
reactor), the required dilution factors were not known prior to the experiment. Therefore in
experiment Air_1, a lot of measured concentrations exceeded the calibrated concentration
range (appendix 5.3.2.).
Figure 7: Experiment Air_2. Concentrations of chlorinated organics at three different places in the system
changing with time. 1.2mg/l of chlorinated organics spiked into a reactor of 300ml distilled water. No current
applied, turbulence generated with a high turbulence magnetic stirrer. Evolving gas sucked through two traps of
82ml dodecane each (1.04l/h). Data points with orange box: Concentration higher than calibration range.
The results of the second experiment can be seen in figure 7. Compared to the experiments
with electrolysis, after three hours the concentrations in the reactor especially for di- and
trichloromethane were not substantially decreasing anymore. The substances partially
stayed in the reactor.
13
The formation of chlorinated organics during electrolytic urine treatment
The results above show that the process of transporting the substances out of the reactor by
applying turbulence is much different from the transport process by stripping with the gas
evolving from the electrolysis. The substances did not enter the traps as fast as in
experiments Blank_1 and Blank_2, where the peak in trap 1 was already detected at 7 hours
after the start. In experiment Air_2, it didn’t even appear after 24 hours (appendix 5.4.2).
Therefore, it was decided to rearrange the system setup back to the electrolysis and accept a
potential loss due to electrolytic reduction. The teflon pipes that were used for the
experiments Air_1 and Air_2 were exchanged with tygon pipes for the next experiment. This
was done to exclude any influence of the fluorocarbon polymers of Teflon, which are
chemically very similar to the chlorinated organics. The peaks in trap 1 and trap 2 in the
beginning indicates that the traps were not sufficiently cleaned after the previous experiment.
For all following experiments, the cleaning process was optimized (additional rinsing with
acetone).
Blank electrolyte spiked with chlorinated organics and a trap volume of 82 ml
(experiment Blank_4)
Figure 8: Experiment Blank_4. Concentrations of chlorinated organics at three different places in the
system changing with time. 1.2mg of chlorinated organics spiked into a reactor of 300ml 1M NaClO4 solution.
2
Applied current density: 5mA/m . Evolving gas sucked through two traps of 82ml dodecane each (1.74l/h). Data
points with orange / grey box: Concentration higher / lower than calibration range.
The results experiment Blank_4 can be seen in figure 8. The data is again consistent with
the characteristics of the substances. Since the concentration in the spiking solution was
much below the saturation concentration, only one phase was detected in the spiking
solution. It is therefore not possible that pure chlorinated organic phases were spiked into the
reactor. This could be a reason for the fact that compared to the experiments Blank_1 and
Air_2, the recovery in the reactor was worse. The detention of chlorobenzene in the first trap
was better than for the other substances: The chlorobenzene concentration in trap 2 is close
to zero until after six hours, for the other substances the concentration in trap 2 already
increases after about three hours.
The data points indicated with gray squares lie below the concentration range of the
calibration. The uncertainty is considered to be big (see chapter 3.1.3).
In the beginning there is a time period where almost no substances can be measured in trap
2 and it can therefore be assumed that the loss out of the system with the gas out of trap 2 is
not very big. This means that ideally everything that leaves the reactor enters trap 1 or trap 2.
14
The formation of chlorinated organics during electrolytic urine treatment
The pink squares in figure 9 indicate the time when the mass balance is calculated. It is
assumed that in this period the reactor was fully mixed and nothing enters the reactor
anymore.
The mass spiked into the reactor is not taken into account for the mass balance, since for
this step the uncertainties are as mentioned very big. For the mass balance it is therefore
assumed that 100% of what can be found in the system is the mass that was maximally
found in the reactor during the experiment. This is a good assumption for all substances
except for tetrachloromethane, which is very insoluble in water (H = 1.10) and immediately
moves to the gas phase.
It is taken into account that there is always both, movement of substance from the gas into
the liquid phase and the other way around. But due to the characteristics of the substances it
is assumed that the resulting flux in the time period where the mass balance is calculated is
always from the reactor into the gas phase and from there into the dodecane trap.
In figure 9 and in appendix 5.5.2, it can be seen that for dichloromethane 41% of the mass
that left the reactor was found in the traps and for trichloromethane it was 79%. There was
more tetrachloromethane found in trap 1 than what was leaving the reactor (131%). This is
as mentioned due to the low solubility of tetrachloromethane in water. Even in a
measurement five minutes after spiking it was not possible to capture all the mass that once
has been in the reactor. For chlorobenzene, 94% of what had left the reactor could be found
in the traps.
Figure 9: Mass balance. Mass found in reactor, trap 1 and trap 2 respectively, divided by the mass
2
maximally found in the reactor. Reactor of 300ml 1M NaClO4 solution. Applied current density: 5mA/m .
Evolving gas sucked through two traps of 82ml dodecane each. Gray data: Low concentration with high
uncertainty, assumed zero. Pink square: Everything that leaves the reactor is expected to end up in the first trap.
For tetrachloromethane and chlorobenzene it can be assumed that everything that has once
been in the reactor can be found in the traps, as long as the substances do not break
15
The formation of chlorinated organics during electrolytic urine treatment
through into the second trap. For di- and trichloromethane, not all of what had been in the
reactor could be found in the traps. The transport was not fast enough so that all the
substance could be transferred from the gas phase into the dodecane, in the time given
inside the trap. In this case the gas bubble is not in equilibrium with the trap, when leaving
the trap.
Between trap 1 and trap 2, the same concept can be applied as between the reactor and trap
1 (appendix 5.5.3). After 3 hours, it was be expected for di-, tri- and tetrachloromethane that
almost nothing entered trap 1 anymore and ideally that everything leaving trap 1 entered trap
2. For tetrachloromethane, this was almost the case (72% recovery) over the whole
experiment duration. Also for trichloromethane, 80% could be recovered until 21 hours after
the experiment start. After 21 hours, the mass of trichloromethane in trap 1 and trap 2
decreased in a similar manner. For dichloromethane, 40% was recovered. For
chlorobenzene, the concentration in trap 1 was increasing over the whole experiment
duration. After an experiment duration of almost two hours, the mass found in trap 1 was
already 2.5 times bigger than the mass spiked in. Due to the consistency of the data it is
assumed that there was no spiking error in this experiment. It is possible that during the
electrolysis, chlorobenzene gets built by a reaction between corroded graphite and chloride
that was left from the voltammetry experiments where the same electrode was used. The
electrodes where rinsed with ethanol and water after the experiment, but due to the porosity
of the graphite it is possible that inside the graphite, there was still a storage of chloride left.
Calculating the mass in the gas and the mass that leaves the system
The concentration in the gas leaving the reactor Cg can be calculated with the mass balance
over trap 1:
𝑚𝑔 = 𝐶𝑔 ∗ (𝑡2 − 𝑡1 ) ∗ 𝑄𝐺 = 𝑉 ∗ (𝐶2 − 𝐶1 )
where V is the trap volume, C2 and C1 are the concentration at time t2 and t1 in the trap where
the gas enters and QG is the gas flow. This is only valid with the assumption, that the gas
bubble is in equilibrium with the dodecane when leaving the trap.
The concentration in the gas leaving trap 1 (and entering trap 2) can also be calculated with
a mass balance. Since trap 1 and trap 2 have an identical setup, the linear correlation of the
gas leaving trap 1 with the concentration in trap 1 can then be applied to trap 2 and thereby
the loss out of the system can be quantified.
The use of this equation is only possible when the concentration in the gas bubble leaving
the trap is in an equilibrium with the concentration in the trap. The linear correlations for di(R2 = 0.70), tri-(R2 0 0.86) and tetrachloromethane (R2 = 0.85) are considered to be
applicable. For chlorobenzene there was no data set where the concentrations in trap 1 and
trap 2 were both in the range of the GC/MS calibration. The values used for the calculation of
the correlation are subject to a high uncertainty and therefore the correlation is less good (R2
= 0.44; see appendix 6).
16
The formation of chlorinated organics during electrolytic urine treatment
3.1.3. Uncertainties
Figure 10: Uncertainties of the measurement method for the analysis of chlorinated
organics production during electrolysis of urine.
In figure 10, the sources of uncertainty in the measurement process are shown
schematically. The main reason for the uncertainties is the volatility of the compound.
Since not enough gas tight syringes were available, the pure chlorinated organics had to be
spiked with vacuum pipettes, which makes it possible that the substances gas out. Another
source of uncertainty is the different sample preparation of the samples from the reactor
and from the traps. For the extraction, the samples were shaken for 10 seconds and then
left standing for 15 minutes before pipetting the dodecane phase (which stands above the
water phase) to the GC/MS vials. It cannot be guaranteed that after this time, all the
chlorinated organics had diffused from the water to the dodecane phase. At a higher
concentration the diffusion is quicker and for chlorobenzene it is assumed to be faster than
for dichloromethane. Since air was sucked through the system, the loss due to leaks is not
considered to be big, but the substances can be hold back on the way on the trap walls, in
the tubes or at the electrode. Another source of uncertainty is the time lag between the
sample preparation and the GC/MS analysis. Because a calibration series is necessary for
every sample series, one experiment was analyzed as a whole. During the experiment, the
already taken samples were stored in the fridge. But it takes almost 45 minutes to analyze
one sample which means that after the analysis started, there was still a long time period
until the last sample got analyzed. In this period, diffusion out of the GC vial was observed,
even though the vials were properly sealed.
The mass spectrometry area that is the result of the GC/MS analysis does only correlate
linearly with the concentration added over a certain concentration range. To get into this
concentration range, the samples from the experiments had to be diluted. But often the
dilution rates could not be chosen ideally because it was not known before the experiment
which concentrations had to be expected. Therefore, some concentrations exceeded the
calibrated concentration range. In this case, the calculated concentration is lower than the
real concentration in the sample because at high concentrations, the GC pillar cannot take
up everything entering it. Below a certain concentration (0.1mg/l for chlorobenzene, 0.05mg/l
for the other substances), the mass spectrum peak is hard to divide from the background
solution (dodecane, syringe cleaning agent). Including the uncertainties, the concentration
then was assumed to be zero. For the calculation of the recovered mass in the recovery
17
The formation of chlorinated organics during electrolytic urine treatment
experiments and for the current efficiency in the urine experiments, only values within the
calibration range were used.
3.1.4. Model of the recovery experiments
A model was developed for the recovery experiments to predict the time range in which
nothing would be lost out of the system and in which therefore it should be possible to get a
consistent mass balance. The underlying assumption of the model was that the gas bubbles
are in equilibrium with the solution when leaving the reactor or the traps (appendix 7.1). The
Berkeley Madonna code can be found in appendix 7.2. Calibrating the model with the data of
experiment Blank_4 did not lead to a satisfying result. The substance transport out of the
reactor is displayed too slow and the concentrations do not match (appendix 7.3). The
assumption of equilibrium probably does not describe the system well enough to achieve a
satisfying calibration. Due to lack of time, the improvement of the model was not pursued.
The next steps would have been the following:
•
•
•
•
Including the KLa value for all substances in the trap into the model, since the
equilibrium assumption may not be appropriate for the traps. For the reactor it is
assumed to be appropriate because the bubbles were very small (about one tenth of
a millimeter) and the retention time of the bubbles was very large because they got
attached to the electrodes before leaving the reactor.
Including the process of surface turbulence in the reactor into the model. In the trap,
the surface is much smaller and the surface turbulence is not thought to have a big
effect.
Improving parameter accuracy: Conduct experiments to find the partition coefficient
of the substances in dodecane instead of hexadecane and to find the henry
coefficient in 1M NaClO4 instead of 1M NaCl.
Conducting several recovery experiments with the same setup and different
parameters (for example changing the gas flow) to calibrate and validate the model.
If it is possible to develop a validated model, it could then be used to analyze the production
of chlorinated organics during electrolysis and to predict the concentration of chlorinated
organics in the gas phase after a certain treatment time.
3.1.5. Summary
The results of the recovery experiments show that the substances move through the system
according to their characteristics. Since the last experiment with the improved trapping
system could not be repeated due to lack of time, it is not sure if the results are reproducible.
The fact that especially for di- and trichloromethane only a part of the substance that left the
reactor could be recovered in trap 1 and trap 2 is an indication that the gas bubble is not in
equilibrium with the liquid phase when leaving the traps. The assumption of equilibrium that
was used for the calculation of the substances in the gas phase might therefore not be
correct for di- and trichloromethane. Quantifying the production of chlorinated organics based
on the here presented data is therefore subject to a big uncertainty. An analysis and
comparison of data from different experiments is still possible because the uncertainties are
expected to be the same for all experiments conducted with stored urine if the same reactor
set up is used. The chlorobenzene measurements are thought to have the lowest
uncertainties because chlorobenzene is best soluble in dodecane and can therefore be
recovered best in the traps and it is also best extracted from the water phase of the samples
from the reactor.
18
The formation of chlorinated organics during electrolytic urine treatment
There are other measurement methods than the one presented in this thesis: Richardson et
al. (2010) injected gas samples directly into the GC/MS. This was not possible here due to
lack of equipment. Choroform in liquid samples was measured using the method of
Lourencetti et al. (2010), but this method is only applicable for trihalomethanes (chloroform,
bromoform etc.) and not for the other substances of interest. Polkowska et al. (2003)
analyzed liquid samples containing di-,tri- and tetrachloromethane with continuous flow thin
layer head space analysis. Also for this method the equipment was not available. Lei et al.
(2007) used dichloromethane as an extraction agent for liquid samples, and Anglada (2011)
used pentane for liquid samples. But since they are both volatile compounds, they are not
applicable in the traps.
3.2.
Cyclic voltammetry experiments
3.2.1. Graphite
The here used graphite electrode consists of graphite and pitch as a binding agent. Graphite
electrodes are cheap, have a large surface area and can combine adsorption and electrolytic
degradation, but the surface corrosion at high currents reduce its life time (Panizza et al.,
2009).
Figure 11: Cyclic voltammetry experiment with a graphite electrode, a graphite counter electrode and a
st
MSE reference electrode. Scan rate: 200mV/s, scan from -1.3V to 1.4V. For all four experiments the 1 cycle of
five cycles is shown. Red lines: Upper and lower potential, chosen for urine experiment with and without formation
of chlorinated organics.
The results of the cyclic voltammetry experiment with a graphite electrode can be seen in
figure 11. In the blank electrolyte, a reduction peak at around 0.9V vs. MSE can be seen.
This might indicate a reaction of the graphite material, for example the reduction of some
surface groups that where oxidized in the higher potential range (1.4V vs. MSE) before.
When ammonia was added, an additional anodic current started at about 0.5V vs. MSE and
had its peak at around 1V vs. MSE. This indicates the oxidation of ammonia. With chloride in
the solution, an additional anodic current started at around 0.9V vs. MSE, which indicates
that chloride oxidation starts. With chloride in the solution, the reduction peak seen in the
blank electrolyte disappeared, instead there was an cathodic peak at around 0.25V vs. MSE.
19
The formation of chlorinated organics during electrolytic urine treatment
The here found results are comparable with the results of an unpublished voltammetry
experiment by Hanspeter Zöllig.
The two potentials for the urine experiment are thus chosen as following:
•
•
Lower potential: 0.8V vs. MSE ( = 1.44V vs. NHE)
Upper potential: 1.3V vs. MSE ( = 1.94V vs. NHE)
3.2.2. Boron doped diamond
Boron doped diamond electrodes are very stable and inert and completely mineralize organic
pollutants with a high current efficiency. The disadvantages of BDD electrodes are their high
costs and the difficulties in finding a substrate for the diamond layer (Panizza et al., 2009).
Chlorine only evolves at a relatively high potential (Kapalka et al., 2010b).
Figure 12: Cyclic voltammetry experiment with a boron doped diamond electrode, a platinum wire as a
counter electrode and a MSE reference electrode. Scan rate: 200mV/s, scan from -2’300mV to 2’200mV. For
st
all four experiments the 1 cycle of five cycles is shown. Red line: Potential, chosen for the urine experiment,
production of chlorinated organics is expected.
The results of the cyclic voltammetry experiment with a boron doped diamond electrode can
be seen in figure 12. Over a wide potential range, there was no current detected at all. This
shows that compared to the graphite and the iridium dioxide electrode, the boron doped
diamond electrode is very inactive in a large potential range. This is due to the fact that
diamond is an electrical insulator and only the boron is able to transport electrons (Fechner
et al., 2001). The electrode material doesn’t get oxidized and reduced.
When ammonia was added, an anodic peak appeared at around 1.2V vs. MSE and had its
maximum at around 2V vs. MSE. Also in the scan back from the higher return potential
ammonia was oxidized. The current was higher than with a blank electrolyte. The chloride
oxidation started at around 1.4V vs. MSE. At 2.2V vs. MSE the current was almost 3 times
higher than with a blank electrolyte. The potential field in which ammonia can be removed
efficiently without any active chlorine produced is very narrow (1.2 V to 1.4V vs. MSE). At the
potential where the highest amount of ammonia gets oxidized, already a lot of active chlorine
got produced.
20
The formation of chlorinated organics during electrolytic urine treatment
With the boron doped diamond electrode only, one experiment was conducted: The potential
for the maximum ammonia oxidation was chosen to find out how much chlorinated organics
have to be expected at the optimum nitrogen removal potential.
Potential: 2V vs. MSE ( = 2.64V vs. NHE)
Also with an iridium dioxide electrode, voltammetry experiments were conducted (appendix
8.1). But Amstutz et al. (2012) found that ammonia oxidation with an iridium dioxide electrode
in urine is inhibited by either oxidation of carbonate or by chlorate formation. It is therefore
considered not to be suitable for ammonia oxidation. No urine experiments were conducted
with an iridium dioxide electrode.
Some additional voltammetry experiments were conducted to test the hypothesis that the pH
drop in the vincinity of the electrode inhibits ammonia oxidation and that this inhibition can be
prevented by applying a low enough potential so that the protons get reduced to hydrogen
gas (appendix 8.2).
3.3.
Urine experiments
Four experiments were conducted for electrolytic treatment of stored urine (table 4). The
data for the urine experiments can be seen in appendix 9. The first experiment with graphite
(Eup_G1) had to be aborted after 4 hours because foam from the reactor entered the traps
and started to clog the bubble diffuser. In the second experiment (EUp_G2) an antifoam
agent was added to the reactor. More dodecane was filled into the traps to have the same
system setup as in the recovery experiments and the experiment was conducted with a
longer experiment duration (Eup_G2). The current density in Eup_G2 was much lower than
in Eup_G1, which is possibly due to the different anodes used in these experiments. In
Eup_G1, the same anode as in Blank_4 was used and in Eup_G2 a new anode was used.
The anode used in Eup_G1 probably has a much higher surface area than the anodes used
in Eup_G2 and Elow_G1 because it has been corroded in Blank_4.
Table 4: Experiment set up and parameters for the electrolytic treatment of urine. Gas evolving from
electrolysis sucked through two traps filled with dodecane. Italic: Controlled parameters. Eup = upper potential:
formation of chlorinated organics expected. Elow = lower potential: No formation expected. Index G = graphite,
index BDD = boron doped diamond.
Potential
Eup_G1
Eup_G2
Elow_G1
Eup_BDD1
Current density Duration
[h]
[V vs. MSE] [mA/cm2]
1.3
50 - 23
1.3
14 - 12.5
0.8
3.5 - 1.4
2.0 / 2.1 3.4 - 1.5 / 2 - 1.7
4:00
29:12
26:00
26:00
Total transTrap volume Gas flow pH
ferred charge
[mA/cm2]
[ml dodecane] [l/h]
[-]
6'703
20
1.82
8.93 - 8.34
26'840
82
1.74
9.01 - 7.34
2'559
20
1.73
9 - 8.85
3'546
20
1.74
8.95 - 8.74
In Elow_G1, the anti-foam agent was added 7 hours after the start of the experiment so that
in the beginning, Eup_G1 and Elow_G1 were still comparable. In Elow_G1, a lower potential
was applied, and therefore, the current density was lower. As in Eup_G2 a new electrode
was used. In Eup_BDD1, the anti-foam agent was added in the beginning of the experiment.
The BDD electrode was used in the voltammetry experiments before. Also for boron doped
diamond, a low current density was expected even though the applied potential was higher
than in all other experiments. This is due to the insulating characteristics of diamond and the
inactivity of the boron doped diamond already discussed in chapter 3.2.2. Another difference
between the experiments is that in Eup_G2 the dodecane volume and therefore the retention
time of the bubbles in the reactor is four times higher than in the other experiments.
21
The formation of chlorinated organics during electrolytic urine treatment
The mass of chlorinated organics evolving over e certain time period can be calculated with
the following equations:
𝒎𝒓 = 𝑉𝑟𝑒𝑎𝑐𝑡𝑜𝑟 ∗ (𝐶𝑟𝑒𝑎𝑐𝑡𝑜𝑟,2 − 𝐶𝑟𝑒𝑎𝑐𝑡𝑜𝑟,1 )
Mass in the reactor liquid:
Mass in the gas phase above the reactor:
𝒎𝒈,𝒕𝒐𝒕 = 𝑉𝑡𝑟𝑎𝑝1 ∗ �𝐶𝑡𝑟𝑎𝑝1,2 − 𝐶𝑡𝑟𝑎𝑝1,1 � +
𝑉𝑡𝑟𝑎𝑝2 ∗ �𝐶𝑡𝑟𝑎𝑝2,2 − 𝐶𝑡𝑟𝑎𝑝2,1 � +
𝑚𝑔,𝑜𝑢𝑡
𝒎𝒈,𝒐𝒖𝒕 = 𝐶𝑔,𝑜𝑢𝑡 �𝑑𝑒𝑝𝑒𝑛𝑑𝑒𝑛𝑡 𝑜𝑛 𝐶𝑡𝑟𝑎𝑝2 � ∗ ∆𝑡 ∗ 𝑄𝐺
Index 2 stands for the end of a certain time step and index 1 for its beginning. The mass lost
in the gas leaving the system is calculated with the relation 𝐶𝑔,𝑜𝑢𝑡 �𝑑𝑒𝑝𝑒𝑛𝑑𝑒𝑛𝑡 𝑜𝑛 𝐶𝑡𝑟𝑎𝑝2 � that
was developed with the data from Blank_4 as described in chapter 3.1.2 and found in
appendix 6.
With a lower current density, a lower production of chlorinated organics is expected, because
less electrons are taken up by the anode in the same time span, which means that less
substance gets oxidized or reduced. To still make an appropriate comparison between the
experiments, they were not compared with the building rates [mg/h] but with the current
efficiency or the “mass produced per transferred charge” [μg/C].
3.3.1. Graphite
In table 5 the average current efficiencies for all compounds for all graphite experiments can
be seen. The development of the mass in the reactor, in trap 1 and in trap 2 with time and
the calculation of the current density can be found in appendix 9.
Table 5: Current efficiencies of the formation of chlorinated organics in electrolytic treatment of stored
urine with graphite electrodes. Potentials applied: Eup_G1 and Eup_G2: 1.3V vs. MSE. Elow_0.8V vs. MSE.
Eup = upper potential: Formation of chlorinated organics expected. Elow = lower potential: No formation
expected. Gray background: Concentrations too low to calculate efficiencies. Yellow background: Current
efficiencies for comparison.
Average current efficiencies over the whole experiment [μg/C]
Eup_G1
Reactor
Gas
Dichloromethane
0.006
0.001
Trichloromethane
0.029
0.02
0
0.001
Tetrachloromethane
Chlorobenzene
Eup_G2
0.004
0.001
Dichloromethane
0
0.002
Trichloromethane
0
0.001
Tetrachloromethane
0
0.0003
Chlorobenzene
Elow_G1
0.001
0.006
Dichloromethane
0
0
Trichloromethane
0
0
Tetrachloromethane
0
0
Chlorobenzene
0
0.002
Total
0.0042
0.0068
0.0024
Due to the higher dodecane volume and the lower current density in Eup_G2 (compared with
Eup_G1), the concentrations of the different substances were often in such a low range, that
including the uncertainties, they had to be assumed zero. This is the same for Elow_G1 with
its even lower current density.
The current efficiencies in Eup_G1 and Eu_G2 differed for all compounds even though the
applied potential was the same. For the gas phase, the current efficiencies for tri- and
22
The formation of chlorinated organics during electrolytic urine treatment
tetrachloromethane were higher in Eup_G1 and the current efficiency for dichloromethane
and chlorobenzene were higher in Eup_G2. The rates in the reactor were generally higher in
Eup_G1 than in Eup_G2.
There are several reasons for the differences between Eup_G1 and Eup_G2: The dodecane
volume in Eup_G2 was four times higher and therefore the retention times in the systems
were different. The new electrode used in Eup_G2 might have produced different substances
than the old one used in Eup_G1. In Eup_G2 anti foam agent was used. The hydrophobic
foam agent might have attracted the substances so that they diffused from the water phase
into the phase of the anti-foam agent, leading to a lower reactor concentration. Additionally,
the treatment time of the first experiment was much shorter. In the model it can be seen that
for chlorobenzene, in the beginning of the treatment the concentration in the reactor
increases faster than in the traps. After about 7 hours, the increase was bigger in the traps
than in the reactor (appendix 7.4). Since the model conceptually describes the given system,
the treatment time could therefore be a reason for the higher current efficiencies in the
reactor in Eup_G1.
Besides the analysis with GC/MS, also Dr. Lange tests for free and total chlorine were
conducted. These tests were originally made for drinking water and not for urine. Since the
urine was diluted ten times, it is assumed that the test has some uncertainties but is still
applicable for comparisons in the range of orders of magnitude. In table 6 it can be seen that
the chloride degradation was best in Eup_G1. In Elow_G1, no chloride got degraded. The
results for bound chlorine, which is a sum parameter for chlorinated organics, are
contradictory to the results from the GC/MS analysis: There was more bound chlorine found
in experiment Eup_G1 than in Eup_G2. The difference could be due to the fact that with
GC/MS, only four substances were measured, while the Dr. Lange test is a sum parameter.
Table 6: Chloride degradation and formation of chlorine in electrolytic treatment of stored urine. Potentials
applied: Eup_G1 and Eup_G2: 1.3V vs. MSE. Elow_G1: 0.8V vs. MSE. G = graphite electrode, BDD = boron
doped diamond electrode.
Removal of Chloride / Production of total and bound chlorine
Transferred charge [C]
Eup_G1
Removal/Production [mg/C]
Eup_G2
Removal/Production [mg/C]
Elow_G1
Removal/Production [mg/C]
Eup_BDD1
Removal/Production [mg/C]
Chloride
Total Chlorine
Bound chlorine
6'703
-0.05
0.0023
0.0015
26'840
-0.01
0.0001
0.00003
3'546
0.07
0.0005
0.0004
2'560
-0.002
0.0005
0.0003
As mentioned in chapter 3.1.5, it is assumed that chlorobenzene has the best measurability.
This is also indicated by the fact that the current efficiency for chlorobenzene could be
calculated in the reactor and the gas phase in almost every experiment (table 5). Therefore,
the comparison of the experiments was done based on the results of chlorobenzene.
Since it was found in the recovery experiment, that for chlorobenzene everything that left the
reactor could be found in the traps, it is assumed that the total current efficiency is the sum of
the one found in the liquid phase and the one in the gas phase (table 5).
Hypotheses
1. Chlorinated organics are formed during the electrolytic treatment of urine.
Since in all experiments chlorinated organics were found, the first hypothesis is accepted.
From the results it cannot be concluded if the chlorinated organics are formed mainly with
acetate, graphite or other carbon species.
23
The formation of chlorinated organics during electrolytic urine treatment
It is assumed that in Eup_G1 the rate of graphite corrosion was the highest, because it had
the highest current density. The highest total graphite corrosion is expected to have
happened Eup_G2 because it had the highest total in transferred charge over the whole
experiment (table 4). The much higher chlorobenzene concentration in Eup_G2 than in
Eup_G1 is an indication that the carbon at least for chlorobenzene might come from the
graphite and that chlorobenzene evolves by the chlorination of the hexagonal carbon
structure of graphite. This indication is confirmed by the results in the recovery experiment
Blank_4, in which additional chlorobenzene was found (figure 8). Acetate and chlorine are
known to react, but the kinetics are considered to be very slow (Kumar et al., 1979). It is
therefore assumed that acetate has to be degraded before it reacts with chlorine and then
leads to the formation of the substances of interest.
Bonfatti et al. (2000b) stated that in electrolytic treatment of glucose (10g/l) mediated by
active chlorine (1 – 10g/l), no chlorinated organics evolved. They used GC/MS and thin layer
chromatography. It is possible that with glucose, no chlorinated organics can be formed.
However, samples were only taken from the liquid phase. It is therefore also possible that
chlorinated organics were actually formed, but because they were stripped out of the reactor,
they were not present in the liquid samples.
The production of chlorinated organics in all three graphite experiments was approximately
linear (appendix 9.5). This was expected since an almost constant current density was
applied for the experiments. In the electrolytic treatment of leachate, Anglada et al. (2011)
also found that trihalomethanes develop close to linearly with time. After a certain time, a
steady state can be expected, with a constant production rate and a constant stripping rate.
2. If the electrode potential applied in electrolytic urine treatment is lower than the
potential needed for chloride oxidation, no chlorinated organics are formed.
In table 6 it can be seen that chlorine was still produced at the lower potential (experiment
Elow_G1). It is therefore plausible that chlorinated organics are still formed (table 5). There
is no sharp potential border between chloride oxidation and no chloride oxidation, so a
potential with absolutely no chloride oxidation would be very low or it might even not be
possible at all. Additionally, the luggin tip (device for potential measurement) and the
electrolyte were not the same for the voltammetry and the urine experiment. It is therefore
possible that the potential applied in the urine experiment differed from the one found in the
voltammetry experiment. Or it is possible that in urine, chloride oxidation is already higher at
a lower potential than in a solution with only natrium perchlorate and chloride.
In table 5 it can be seen that the total current efficiency for chlorobenzene in Elow_G1 was
lower than in Eup_G2 and in Eup_G1. This is an indication that at a lower potential, a lower
amount of chlorinated organics are formed. But the comparison of the experiments is subject
to a high uncertainty: The setup of the experiments is not fully comparable. The comparability
of Eup_G1 and Elow_G1 is given by the same dodecane volume in the traps, but an old
electrode was used in Eup_G1. The comparability between Eup_G2 and Elow_G1 is given
by the fact that in both experiments new electrodes were used, but the trap volume differs.
It is possible that the chlorinated organics which were produced somehow adsorbed at and
diffused into the anode, and therefore not all of the substances were found in the reactor or
traps. The effect would have been bigger in Eup_G1 than in the other experiments because
the old electrode in Eup_G1 is assumed to have had a much higher absorbance capacity
and porosity due to the corrosion. In table 6 it can be seen that in Eup_G1 much more bound
24
The formation of chlorinated organics during electrolytic urine treatment
chlorine was produced compared to the other two experiments. It is therefore possible that in
Eup_G1, less of the substances of interest but more of other compounds that were not
measured, were produced.
3.3.2. Boron doped diamond
Figure 13: Production of chlorinated organics during electrolytic treatment of urine. Boron doped diamond
anode and graphite cathode. Applied potential: 2V vs. MSE. 300ml of stored urine. Evolving gas sucked through
two traps of 20ml dodecane each (gas flow: 1.74l/h). Data points with orange box: Concentration higher than
calibration area.
The results of the experiment with a boron doped diamond electrode can be seen in figure
13. As expected, chlorinated organics got produced. A high concentration of chlorinated
organics could be measured in all parts of the system after two hours, but after 4 hours the
concentration decreased again to close to zero (apart from chlorobenzene).
The COD (chemical oxygen demand = sum parameter for organic substances) and chloride
measurements show that after 4 hours there was no limitation of organic compounds or
chloride that could limit the production of chlorinated organics (appendix 10). It is possible
that only a very small part of organic compounds is available for the production of chlorinated
organics and this was used up after four hours. But since the current density is higher in
Eup_G1 and Eup_G2 than in Eup_BDD1, the limitation should also appear there.
Additionally, the chlorobenzene concentration started to increase at the end of the
experiment without any inhibition. The cathode used in Eup_BDD1 was already used before
in Eup_G1 and Eup_G2. It is possible that a storage of chlorinated organics remained after
Eup_G2. But graphite cathodes do not corrode and the storage in this experiment probably
could not lead to amounts higher than in the other experiments (for comparison see appendix
9.5). Additionally, the effect should also have been seen in the prior experiments, since the
cathode was used in all of them. There was less chloride oxidized in Eup_BDD1 than in
Eup_G1 and Eup_G2 (table 6), therefore it is not plausible that more chlorinated organics
were produced. The experiment has to be repeated to exclude a measurement error. The
current efficiency of chlorobenzene over the whole experiment, not including the high sample
point after two hours, was 0.003 μg/C. It was lower than in Eup_G2 and Eup_G1, but higher
than in Elow_G1.
3.3.3. Concentrations in the gas leaving the system
In the urine experiments (apart from Eup_G2), the dodecane volume was only quarter as big
as in Blank_4. This means that in these urine experiments, the retention time of the bubbles
25
The formation of chlorinated organics during electrolytic urine treatment
in the traps was much shorter than in Blank_4. It is therefore assumed that in the shorter
time spent in the dodecane, less substance could be transferred from the gas to the liquid
phase and compared to Blank_4, more was lost with the gas leaving the system.
Additionally, the concentrations in the gas phase in the urine experiments were lower than in
Blank_4. This also leads to a less efficient diffusion.Due to the above described differences
in the system setups, it can be assumed that the loss with the gas leaving the system was
higher in the urine experiments than in Blank_4. The loss in the urine experiments, which has
been calculated with data from Blank_4 (as described in chapter 3.1.2.), is therefore
underestimated. The higher current efficiencies of some substances in Eup_G2 might
therefore be due to the fact that in Eup_G2 the same trap volume as in Blank_4 was used
and therefore the loss was calculated more accurately (table 5).
3.3.4. Nitrogen and COD degradation
The degradation of nitrogen and COD in all urine experiments can be seen in table 7.
Table 7: Removal of nitrogen and COD / Production of nitrate and nitrite in 4 experiments for
potentiostatic electrolytic treatment of stored urine. G = graphite anode, BDD = boron doped diamond
electrode. Applied potentials: Eup_G1 and Eup_G2: 1.3V vs. MSE. Elow_G1: 0.8V vs. MSE. Eup_BDD1: 2V vs.
MSE. Total nitrogen = ammonia + nitrite + nitrate.
Removal of Nitrogen and COD
Transferred charge [C]
Eup_G1
Removal/Production [mg/h]
Removal/Production [mg/C]
Eup_G2
Removal/Production [mg/h]
Removal/Production [mg/C]
Elow_G1
Removal/Production [mg/h]
Removal/Production [mg/C]
Eup_BDD1
Removal/Production [mg/h]
Removal/Production [mg/C]
Total Nitrogen Ammonia
Nitrite
Nitrate
6'703
6'703
-86
-0.05
-105
-0.06
0.37
0.0002
18
0.011
26'840
26'840
-21
-0.02
-37
-0.04
0.9
0.001
15
0.016
2'560
2'560
-13
-0.14
-17
-0.12
0.03
0.0002
0.12
0.001
3'546
3'546
-16
-0.12
-14
-0.14
0.001
0.00001
0.5
0.005
COD
-23
-0.17
Eup_G1 and Eup_G2 showed a better nitrogen removal rate than Elow_G1 and Eup_BDD1.
But the current efficiency was much better in Elow_G1 and Eup_BDD1: More ammonia was
degraded, while less nitrate and nitrite was produced. If it is assumed that at a lower potential
less chlorine is produced, this means that less chlorine does not lead to a lower nitrogen
removal. It is assumed that at a lower potential there are less reactions that compete for
current (e.g. less oxygen evolution). To reach the same degradation, the treatment time has
to be longer with a boron doped diamond electrode and a graphite electrode with the lower
potential than with a graphite electrode and the upper potential, since the current density is
lower.
Only for Eup_BDD1, COD measurements could be made because corroded graphite
interferres with the COD measurement. In appendix 10, it can be seen that with 3’546
coulomb transferred in a treatment time of 26 hours, a total of almost 600mg of COD were
removed. If it is assumed that the measurement after two hours was an error, a total of less
than 0.01mg of chlorobenzene was produced. It can be seen that only a very small part (ca.
0.002%) of the degraded organic substance ends up as chlorobenzene.
3.3.5. Comparison of the graphite and the boron doped diamond electrode
In electrolytic treatment of stored urine with a graphite electrode (compared with a boron
doped diamond electrode), less nitrogen gets removed per charge with a higher production
of nitrate and nitrite. The corrosion of graphite leads to the requirement of an additional
treatment step to remove the corroded particles.
26
The formation of chlorinated organics during electrolytic urine treatment
With a boron doped diamond electrode, more nitrogen gets removed per charge and less
nitrite and nitrate get produced. This was expected since boron doped diamond electrodes
are known for their complete pollutant oxidation (Panizza, 2009). The higher ammonia
oxidation per charge is also indicated in the voltammetry experiments, since the current only
contributing to the ammonia oxidation (without the reactions of the electrode material itself) is
much higher with a boron doped diamond electrode than with a graphite electrode (figure 11
and figure 12). With a boron doped diamond electrode, the current efficiencies for the
formation of chlorinated organics is lower than with a graphite electrode, if the sample with a
high concentration is assumed to be a measurement error.
The price of the boron doped diamond electrode is assumed to be much higher than for the
graphite electrode. But since boron doped diamond is very inert and doesn’t corrode, its
lifetime is much longer than the one of graphite (Panizza, 2009). In a long-term analysis, the
costs of a boron doped diamond electrode might get amortized earlier than several graphite
electrodes in the same time span. If the goal of the treatment step is fertilizer production, a
graphite anode with a higher potential might be better suited than a boron doped diamond
electrode because more nitrate is produced.
4. Conclusion and outlook
Development of a measurement method for chlorinated organics
The substances of interest can be measured in the developed system. They could not be
held in the traps permanently but got stripped out again after a certain time, depending on
their characteristics. For chlorobenzene and tetrachloromethane, dodecane is a good
trapping agent, but not for dichloromethane. To achieve more efficient trapping, to reduce
uncertainties and to get statistically relevant results, the following actions have to be taken:
•
•
•
•
•
•
The experiment Blank_4 with its improved reactor setup has to be repeated to show
that the results are reproducible.
The residence time and the diffusion efficiency in the traps have to be increased by
increasing the trap height and decreasing the bubble size.
Gas tight syringes have to be used.
To be able to achieve a complete extraction, experiments have to be conducted,
where the movement of the substances from the water to the dodecane phase can be
documented and therefore an optimal extraction process can be developed.
To be sure that graphite does not contribute to any production of chlorinated organics
during the recovery experiments, another electrode than graphite has to be used, e.g.
iridium dioxide or boron doped diamond.
To better characterize the substances, experiments to find the partition coefficient of
the substances in dodecane have to be conducted.
There are alternatives to the measurement method, but as described in chapter 3.1.5 there
was either no equipment or not enough time for the development of such measurement
methods, or the methods were not suitable for the substances of interest or the system
setup.A possible alternative to the here presented method is to analyze only one substance
as an indicator for the other substances of interest.
Urine experiments
Below, the two hypotheses are listed again:
1. Chlorinated organics are formed during the electrolytic treatment of urine.
27
The formation of chlorinated organics during electrolytic urine treatment
In electrolytic treatment of stored urine, chlorinated organics as di-, tri-, tetrachloromethane
and chlorobenzene get produced. Therefore the first hypothesis can be accepted. A
significant part of the produced substances was found in the gas phase and not in the liquid
phase. It has been shown in the experiments that the type of electrode and the applied
potential have an influence on the formation of chlorinated organics.
2. If the electrode potential applied in the electrolytic urine treatment is low enough
so that no chloride oxidizes, no chlorinated organics are formed.
The second hypothesis cannot be accepted because also at the lower potential chlorinated
organics were formed. To find a potential at which absolutely no chlorinated organics are
formed, might be difficult (chapter 3.3.1). In the experiment with a lower potential (Elow_G1),
less chlorobenzene was formed than in the experiments with a higher potential (Eup_G1 and
Eup_G2). It is therefore still thought to be a good strategy to control the formation of
chlorinated organics by lowering the potential. In future experiments the potential could be
stepwise decreased and toxicity measurements could be conducted to find a potential at
which the concentration of the produced chlorinated organics is not harmful.
The following actions have to be taken to be able to decrease uncertainties, to get
statistically significant results and to further analyze the formation process:
•
•
•
•
•
•
•
All experiments have to be conducted with new electrodes and repeated to show that
the results are reproducible.
For the urine experiments, the same experiment setup as in the recovery experiments
has to be used to be able to representatively quantify the loss.
The measurability of the compounds has to be increased by decreasing the trap
volume (but not the height).
The same luggin tip (device for potential measurement) has to be used for the
voltammetry and the urine experiments.
The experiment with the boron doped diamond anode has to be repeated with
another cathode than graphite.
An experiment where active chloride is mixed into the urine has to be conducted
without electrolysis to find if the reaction for chlorinated organics formation is
happening in the bulk phase or if an electrode surface is needed for the reaction.
An electrolysis experiment in which a solution of only acetate and chloride is added
has to be conducted to inquire if acetate is the carbon source.
Impact on the VUNA project
Ammonia was oxidized in all experiments. If the goal of ammonia oxidation is fertilizer
production, it is better to use a graphite electrode because like that more nitrate is produced
than with a boron doped diamond electrode. With a boron doped diamond anode less
chlorinated organics got produced. For safety reasons it is therefore better to use boron
doped diamond. However, a cost calculation has to be included.
A substantial part of the chlorinated organics moves to the gas phase. If the formation of
chlorinated organics cannot be prevented during the electrolysis of stored urine, the
electrolysis reactor should be built in open air to dilute the chlorinated organics in the
atmosphere. Since it is assumed that the more toxic chlorinated organics (e.g.
chloromethane) are the more volatile ones, the gas phase has always to be taken into
account.
28
The formation of chlorinated organics during electrolytic urine treatment
5. Acknowledgements
Hereby I would like to thank the following people, without whom my master thesis would not
have been possible:
•
•
•
•
•
•
Hanspeter Zöllig and Kai Udert, for their excellent supervision, their always open door
and all the interesting discussions.
Eberhard Morgenroth for his helpful comments in the intermediate meetings.
The teams from the technical support (especially Peter Gäumann), for supplying me
with materials and for the bike I could use to drive to Eawag.
Claudia Bänninger and Karin Rottermann for the IC analysis and the assistance with
ordering material.
Joachim Mohn from Empa, for lending me his bubble meter.
My family and friends.
Picture: A graphite anode and cathode, a luggin tip and a pH-meter in a electrolyzed solution
of 1M NaClO4 containing Dichloromethane, Trichloromethane, Tetrachloromethane and
Chlorobenzene (Picture: Cristina Fritzsche, July 2012).
29
The formation of chlorinated organics during electrolytic urine treatment
6. References
Abraham, M.; Andonian, J. et al. (1994) Hydrogen Bonding. Part 34. The Factors that Influence
the Solubility of Gases and Vapours in Water at 298 K, and a New Method for its Determination.
Journal of Chemical Society, Perkin Transactions 2. 1777-1791.
Anderson, K., Hardt, J. et al. (1957) Self diffusion in liquids. 11. Comarison between mutual and
self-diffusion coefficients. Journal of Physical Chemistry 62 (4). 404-408.
Anglada, A.; Urtiaga, A. et al. (2009) Contributions of electrochemical oxidation to waste-water
treatment: fundamentals and review of applications. Journal of chemical technology and
biotechnology, 84. 1747-1755.
Anglada, A.; Urtiaga, A. et al. (2010) Boron-doped diamond anodic treatment of landfill leachate:
Evaluation of operating variales and formation of oxidation by-prodcts. Water research, 45. 828838
Anglada, A.; Urtiaga, A. et al. (2011) Boron-doped diamond anodic treatment of landfil leachate:
Evaluation of operating variables and formation of oxidation by-products. Water research 45. 828838.
Amstutz, v.; Katsaounis, A. et al. (2012) Effects of carbonate on the electrolytic removal of
ammonia and urea from urine with thermally prepared IrO2 electrodes. Manuscript Draft.
Unpublished.
Bonfatti, F.; De Battisti, A. et al. (2000a) Anodic mineralisation of organic substrates in chloridecontaining aqueous media. Electrochemica acta, 46, 305-314.
Bonfatti, F.; Ferro, S. et al. (2000b) Electrochemical incineration of glucose as a model organic
substrate. II. role of active chlorine mediation. Journal of the electrochemical society, 147. 592596.
Bullister, J. and Wisegarver, D. (1998) The solubility of carbon tetrachloride in water and
seawater, Deep-Sea Research I 45, 1285-1302.
Ciba-Geigy, 1977. Wissenschaftliche Tabellen Geigy, Teilband Körperflüssigkeiten (Scientific
Tables Geigy. Volume: Body Fluids), 8th ed. Basel. In German.
Czanetzki, L.R. and Jansen, J.J. (1991) Formation of hypochlorite, chlorate and oxygen during
NaCl electrolysis from alkaline solutions at am RuO2/TiO2 anode. Journal of applied
electrochemistry, 22. 315-324.
Eawag (2010). VUNA, Nutrient Harvesting in South Africa.
http://www.eawag.ch/forschung/eng/gruppen/vuna/index_EN. Last visited: 27.7.2012
Fechner, A.; Kramer, B. (2001) Semiconductor Quantum Structures. Subvolume B, Electronic
Transport. Numerical Data and Functional Relationships in Science and Technology. Springer,
Berlin.
Frenkel, M.; Hong, X. et al. (2002). Thermodynamic Properties of organic compounds and their
mixtures, Numerical Data and Functional Relationships in Science and Technology, Group IV:
Physical Chemistry, Volume 8. Springer Verlag.
Hand, D.; Hokanson, R. et al. (2003) Air stripping and aeration. Department of Civil and
Environmental Engineering. Michigan Technological University
Hansen, C. (1967) The three dimensional solubility parameter and solvent diffusion coefficient.
Danish technical press.
Herbert, A.; Forestier, D. et al. (2010) Innovative method for prioritizing emerging disinfection byproducts (DBPs) in drinking water on the basis of their potential impact on public health. Water
research 44. 3147-3165.
Ikematsu, M.; Kaneda, K. et al. (2006) Electrolytic treatmen of human urine to remove nitrogen
and phosphorus. Chemistry letters, 35. No. 6.
Ikemasu, M.; Kaneda, K: et al. (2007) Electrochemical treatment of human urine for its storage
and reuse as flush wáter. Science of the total environment 382. 159-164.
30
The formation of chlorinated organics during electrolytic urine treatment
Kapalka, A.; Katsaounis, A. et al. (2010a) Ammonia oxidation to nitrogen mediated by
electrogenerated active chlorine on Ti/PtOx-IrO2. Electrochemistry communications, 12. 12031205.
Kapalka, A.; Joss, L. et al. (2010b) Direct and mediated electrochemical oxidation of ammonia on
borod-doped diamond electrode. Electrochemistry communications, 12.1714-1717.
Kapalka, A.; Fierro, S. et al. (2011) Electrochemical oxidation of ammonia (NH4+ / NH3) on
thermally and electrochemically prepared IrO2 electrodes. Electochimica acta 56, 1361-1365.
Laureni M., Wächter M., Durciova B., Mohn J. and Udert K.M. (2012). Transformations and
losses of major urine compounds in a urine-collecting systems. To be submitted to Water
Research.
Lei, Y.; Shen, Z. et al. (2007) Treatment of landfill leachate by combined age-refuse bioreactor
and electro-oxidation. Water research 42. 2417-2426.
Lourencetti, C.; Ballester, C. et al. (2010) New method for determination of trihalomethanes in
exhaled breath: Applications to swimming pool and bath environments. Analytica Chimica Acta
662, 23–30
Macey, R. and Oster, G. (2001) Berkeley Madonna. Modeling and analysis of dynamic systems.
http://www.berkeleymadonna.com. Last visited: 28.07.2012
Panizza, M.; Cerisola, G. (2009) Direct and mediated anodic oxidation of organic pollutants.
Chemical reviews, 109, 6541-6569.
Polowska, Z.; Kozlowska, K. et al. (2003) Relationship between volatile organohalogen
compounds in drinking water and human urine in Poland. Chemosphere, 53, 899-909.
Putnam, D.F. (1971) Composition and concentrative properties of human urine. NASA contractor
report. National aeronautics and space administration (NASA), Washington DC.
Richardson, S.; DeMarini, D. et al. (2010) What’s in the Pool ? A comprehensive identification of
disinfection by-products and assessment of mutagenicity of chlorinated and brominated
swimming pool water. Environmental health perspectives 118. 1523-1529.
Schwarzenbach, R.; Gschwend, P. et al. (2003) Environmental Organic Chemistry. Second
Edition. John Wiley & Sons Publications.
Udert, Kai (2010) Promoting sanitation and nutrient recovery through urine separation. A
Proposal Submitted to the Bill and Melinda Gates Foundation. Eawag, Switzerland.
de Vooys, A.; Koper , M. et al. (2001) The role of adsorbates in the electrochemical oxidation of
ammonia on noble and transition metal electrodes. Journal of Electroanal. Chemistry 506, 127–
137.
Vlyssides, A. and Israilides, C. (1997) Detoxification of tannery waste liquors with an electrolysis
system. Environmental Pollution 97, 147-152.
Xie, W.; Zheng, Z. et al. (1994) Solubilities and Activity Coefficients of Chlorobenzenes and
Chlorophenols in Aqueous Salt Solutions. Journal of Chemical and Engineering Data 39, 568571.
31
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Appendix
The formation of chlorinated
organics during electrolytic urine
treatment
Master thesis of Cristina Fritzsche
1
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Table of Contents
1.
Constituent of fresh and stored urine ......................................................................... 4
1.1.
Organic Compounds................................................................................................ 5
2.
Conducted experiments and their characteristics ..................................................... 6
3.
Screening experiment .................................................................................................. 7
4.
Calibration solution production .................................................................................. 8
5.
Recovery experiments ................................................................................................. 9
5.1.
Experiment Blank_1 ................................................................................................ 9
5.1.1.
5.2.
Experiment Blank_2 .............................................................................................. 12
5.2.1.
5.3.
Data ................................................................................................................. 9
Data ............................................................................................................... 12
Experiment Air_1 ................................................................................................... 20
5.3.1.
Data ............................................................................................................... 20
5.3.2.
Concentration changing with time: Graph ....................................................... 27
5.4.
Experiment Air_2 ................................................................................................... 28
5.4.1.
Data ............................................................................................................... 28
5.4.2.
Concentration changing with time: Graph ....................................................... 36
5.5.
Experiment Blank_4 .............................................................................................. 37
5.5.1.
Data ............................................................................................................... 37
5.5.2.
Mass balance: Reactor vs. tap 1 and trap 2.................................................... 45
5.5.3.
Mass balance: trap 1 vs. Trap 2 ..................................................................... 46
6.
Correlation: Trap vs. gas leaving the trap ................................................................ 47
7.
Model ........................................................................................................................... 48
8.
7.1.
Concept ................................................................................................................. 48
7.2.
Berkeley Madonna Code ....................................................................................... 49
7.3.
Fitted model .......................................................................................................... 51
7.4.
Chlorobenzene concentration over time ................................................................ 52
Additional voltammetry experiments ........................................................................ 52
8.1.
Iridium dioxide electrode........................................................................................ 52
8.2. Changes in ammonia oxidation peaks with increasing cycle number with three
different electrodes .......................................................................................................... 54
2
Appendix: Formation of chlorinated organics during electrolytic urine treatment
9.
Urine experiments ...................................................................................................... 55
9.1.
Data - Experiment Eup_G1.................................................................................... 55
9.2.
Data - Experiment Eup_G2.................................................................................... 59
9.3.
Data - Experiment Elow_G1 .................................................................................. 67
9.4.
Data - Experiment Eup_BDD1 ............................................................................... 69
9.5.
Comparison ........................................................................................................... 72
9.5.1.
Experiment Eup_G1 ....................................................................................... 72
9.5.2.
Experiment Eup_G2 ....................................................................................... 72
9.5.3.
Experiment Elow_G1 ...................................................................................... 73
10. Concentration (mg/l): Ammonia, nitrate, nitrite, chloride, chlorine, phosphate,
sulphate and COD ............................................................................................................. 74
Cover picture appendix: Bastian Etter
3
Appendix: Formation of chlorinated organics during electrolytic urine treatment
1.
Constituent of fresh and stored urine
Fresh Urine
Parameter
Unit
Urine (male)
COD
Ntot
NH3
Urea
Cl
PO4
SO4
Na
K
Ca
Mg
Alk
pH
EC
[mg/l]
[mgN/l]
[mgNH3-N/l]
[mgN/l]
[mgCl/l]
[mgPO4-P/l]
[mgSO4 /l]
[mgNa/l]
[mgK/l]
[mgCa/l]
[mgMg/l]
mmol CaCO3 /l
[-]
[mS/cm]
7580
6240
272
5306
3861
325
891
1952
1963
48.6
29.7
21.9
6.4
21.1
±
±
±
±
±
±
±
±
±
±
±
±
±
±
4697
3541
193
3088
2034
255
648
999
1266
33.7
19.4
13.8
0.5
18.9
Volume
Voids
VolVoid
[l/day]
[voids/day]
[l/void]
1243 ±
3.6 ±
0.35 ±
454
1.2
0.1
Samples
[-]
18
Fresh Urine
COD
Ntot
NH3
Urea
Cl
PO4
SO4
Na
K
Ca
Mg
Alk
pH
EC
Samples
Unit
[mg/l]
[mgN/l]
[mgNH3-N/l]
[mgN/l]
[mgCl/l]
[mgPO4-P/l]
[mgSO4 /l]
[mgNa/l]
[mgK/l]
[mgCa/l]
[mgMg/l]
mmol CaCO3 /l
[-]
[mS/cm]
[-]
±
±
±
±
±
±
±
±
±
±
±
±
±
±
NH3
Urea
8.8%
1.5%
34.1%
4.0%
Cl
PO4
SO4
Na
17.4%
K
1.2%
23.9%
Ca
Mg
Stored urine
Urine (male)
6759
2535
2291
29
2888
183
514
1817
1401
22
1
154
9
24
COD
8.8%
Stored Urine
Parameter
0.1%
0.2%
1455
138
113
36
113
12
51
860
80
24
0
9
0
1
0.1%
0.0%
COD
8.8%
NH3
Urea
11.4%
3.2%
42.5%
1.1%
Cl
PO4
SO4
Na
18.2%
K
Ca
0.2%
14.4%
Mg
11
Figure 1: Constituents of fresh and stored male Urine (Laureni et al., 2012).
Source: Laureni M., Wächter M., Durciova B., Mohn J. and Udert K.M. (2012).
Transformations and losses of major urine compounds in a urine-collecting systems. To be
submitted to Water Research.
4
Appendix: Formation of chlorinated organics during electrolytic urine treatment
1.1.
Organic Compounds
Fresh Urine
Figure 2: Organic compounds in fresh urine.
Stored Urine
Figure 3: Organic compounds in stored male urine.
Source: Presentation “Bioelectrochemical Systems - An Option for Decentralized Urine
Treatment?” of Kai Udert, 2012.
5
Appendix: Formation of chlorinated organics during electrolytic urine treatment
2. Conducted experiments and their characteristics
SCREENING EXPERIMENT, Goal: find chlorinated organics present in electrochemically treated urine
Name
Difference to previous experiment
Potential
[V vs. MSE]
120411_DBPs_E1.3
Current density Trap Volume Gas flow
Duration
[mA/cm2]
[ml]
[l/h]
[h]
0.86
50 - 8
3/2
none
24:00
CALIBRATION EXPERIMENTS, Goal: Calibration of the GC/MS
Name
Difference to previous experiment
120503_Dspike_1
120507_Dspike_2
120508_Dspike_3
120516_Blank1_ST
120523_Blank2_ST
120606_ST
120621_Air1_ST
120706_Blank4_ST
120717_Uup_BDD1_ST
test higher concentration range
test middle concentration range
set final concentration range / use for Blank1
renew Calibration curve
renew Calibration curve / use for Blank2
renew Calibration curve / use for Air1 / Air2
renew Calibration curve / use for Blank4 / Uup_G
renew Calibration curve / use for Uup_BDD1
Concentration range
[mg/l]
0.01 - 1
0.2 - 100
2 - 15
0.2 - 1.5
0.2 - 1.5
0.2 - 1.5
0.2 - 1.5
0.2 - 1.5
0.2 - 1.5
RECOVERY EXPERIMENTS, Goal: Recovery of mass spiked into system
Name
Difference to previous experiment
120516_Blank_1
120523_Blank_2
120531_Blank_3
120620_Air_1
120629_Air_2
120704_Blank_4
more samples in the beginning, slightly bigger traps
renew dodecane volume
no dillusion
addapt dillusion due to Air_1
bigger trap volume, no teflon tubes
Potential
[V vs. MSE]
Current density Trap Volume Gas flow
Duration
[mA/cm2]
[ml]
[l/h]
[hh:mm]
1.1
4.93
10
1.24
46:00
1.18
4.93
12
7.12
24:40
stop experiment due to brok en trap
82
0.78
27:45
82
1.04
27:30
1.52
4.93
82
1.74
51:30
VOLTAMMETRY EXPERIMENTS, Goal: Find upper and lower Potential for urine experiments
Name
Difference to previous experiment
120511_V_G1
120522_V_Ir1
120607_V_G2
120612_V_G3
120613_V_BDD1
120613_V_BDD2
120626_V_Gmix
change upper potential in the range given in next column
lower Potential
[V vs MSE]
-1.3
-1.3
-1.3
-1.3
-2.3
-2.3
(-1.3) - (-2.3)
upper Potential
[V vs MSE]
0.6 - 1.2
0.1 - 0.9
0.6 - 1.5
0.9 - 1.4
1.0 - 2.2
1.0 - 2.2
1.35
Name
120710_Uup_G1
120711_Uup_G2
120717_Uup_BDD1
120719_Ulow_G1
Kathode Potential
[V vs. MSE]
2.66 - 2.17
2.02 - 1.99
1.78 - 1.68 / 1.8 - 1.78
1.75 - 1.67
URINE EXPERIMENTS, Goal: Reject / accept hypothesis
Name
Difference to previous experiment
120710_Uup_G1
120711_Uup_G2
bigger traps, longer experiment, anti foam agent, new anode
120717_Uup_BDD1
increase potential after 6 hours to increase current density
120719_Ulow_G1
new anode, same cathode as in previous experiments
italic = controlled value
Anode Potential
[V vs. MSE]
1.3
1.3
2.0 / 2.1
0.8
Current density Trap Volume Gas flow
[mA/cm2]
[ml]
[l/h]
50 - 23
20
1.82
14 - 12.5
82
1.74
4.5 - 1.9
20
1.74
10 - 1.4
20
1.73
pH
[-]
8.93 - 8.34
9.01 - 7.34
8.95 - 8.74
9 - 8.85
Duration Totally transferred Charge
[h]
[C]
4:00
6'703
29:12
26'840
26:00
3'546
26:00
2'559
6
Appendix: Formation of chlorinated organics during electrolytic urine treatment
3. Screening experiment
Figure 4: Mass spectrum of the sample from trap 1 (3ml) after 24 hours of electrolytic treatment of stored urine.
Dichloromethane, trichloromethane, tetrachloromethane and chlorobenzene were chosen as substances of interest. The peak of trichloromethane is
overlain by the peak of syringe flushing fluid which has a similar mass. Concerning toxicity and occurrence, chloromethane would have been another
important substance, but since it is gaseous at room temperature it would have complicated the production of the calibration solutions.
7
Appendix: Formation of chlorinated organics during electrolytic urine treatment
4. Calibration solution production
Standards CG/MS: 12/06/06
Stock solution 1:
Concentration:
Volume:
Mass:
1000 mg/l
200 ml
0.2 g in 200ml
Stoffe
Dichloromethane
Trichloromethane
Tetrachloromethane
Chlorobenzene
[μl]
152
135
126
182
Dodecan
Stock solution 2:
Concentration:
Volume:
Mass:
20 mg/l
50 ml
0.001 g in 50ml
Stock solution 1
1'000 μl
Dodecan
150
140
130
180
200.000 ml
Molar Mass
Density
g/mol
g/l
Dichloromethane
84.93
1'316
Trichloromethane
119.38
1'479
Tetrachloromethane
153.82
1'584
Chlorobenzene
112.56
1'101
49 ml
Concentration
Volume
Mass
0.2 mg/l
10 ml
0.000002 g in 10ml
Stock solution 2 [μl]
100
300
500
750
9.900
9.700
9.500
9.250
Dodecan [ml]
Dodecane total:
0.6 mg/l
10 ml
0.000006 g in 10ml
1 mg/l
10 ml
0.00001 g in 10ml
1.5 mg/l
10 ml
0.000015 g in 10ml
287.350 ml
Figure 5: Procedure for the production of standard solutions for the GC/MS analysis of samples from electrolytic treatment of urine.
The correlation between mass spectrometry area and concentration was described with a linear function. The intersection of the y and the x axis was
not included in this linear function. The comparison of this concentration values with the concentration values calculated including the interception
showed, that the difference is in a percentage range. Only at low concentrations where the uncertainty is already high due to the low measurability, the
difference can be higher (appendix xx). Therefore it was decided to use the values calculated without including the intersection point.
8
Appendix: Formation of chlorinated organics during electrolytic urine treatment
5. Recovery experiments
N/A = peak not available = not found
Orange: sample above the concentration range
Gray: sample below the concentration range
Green: liquid samples
5.1.
Blue: best range
Purple: assumed value
Average: Chosen value
Experiment Blank_1
5.1.1. Data
In Blank 1 the sample names from the GC/MS analysis and from the evaluation do not
correspond.
Dichloromethane
Results from the GC/MS analysis
Com ponent Nam e
Dichlormethan_84
Sam ple Nam e
0.2_1
0.6_1
1_1
1.5_1
2_1
0.2_2
0.6_2
1_2
1.5_2
2_2
1_liquid
2_gas_1
2_gas_2
3_liquid
4_gas_1
4_gas_2
5_liquid
6_gas_1
6_gas_2
6_gas_1_undil
6_gas_2_undil
7_liquid
8_gas_1
8_gas_2
8_gas_1_undil
8_gas_2_undil
9_liquid
Area
2962317
8054976
12693104
19615180
24452081
2959439
8160843
12966421
19107480
24616625
32043699
11339763
19453665
11768402
10681095
9675231
5244434
1727025
2772059
8939119
9189108
945957
983691
1037652
4053610
4871580
1313775
Equation
Y = 552002+1.22185e+007*X R^2 = 0.9981
Standards
Know Conc Calculated Conc
0.200
0.197
0.600
0.614
1.000
0.994
1.500
1.560
2.000
1.956
0.200
0.197
0.600
0.623
1.000
1.016
1.500
1.519
2.000
1.970
2.577
0.883
1.547
0.918
0.829
0.747
0.384
0.096
0.182
0.686
0.707
0.032
0.035
0.040
0.287
0.354
0.062
Specified
%Diff
-1%
2%
-1%
4%
-2%
-1%
4%
2%
1%
-2%
Calculated
%RSD
0.1%
1.0%
1.6%
1.9%
0.5%
0.1%
1.0%
1.6%
1.9%
0.5%
Dilusion:
assume
high
Dillusion
Reactor
Trap 1
Trap 2
low
1
1
4
Average
1
4
8
10
Average
1.00
4
8
10
Average
best range
2
3
10.31
10.31
3.672
3.67
0.00
3.532
4
1.536
1.54
5
0.032
0.062
0.03
0.69
0.385
0.06
0.29
0.283
0.00
3.53
0.00
6.19
8.290
8.29
0.54
0.71
0.73
0.28
0.35
0.32
0.00
6.19
7.47
7.47
0.73
0.35
9
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Calculated concentrations and masses:
Tim e vs Concentration, Mass
Sample Nr.
1
2
3
4
5
Sample Nr.
1
2
3
4
0.3
Reactor
Time since start [h] eff. Conc [mg/l]
0:00
10.31
1:30
3.67
4:15
1.54
24:00
0.03
46:00
0.06
Time
16.05.2012 12:15
16.05.2012 13:45
16.05.2012 16:30
17.05.2012 12:15
18.05.2012 10:15
Trap 1
eff. Conc [mg/l]
Trap Volume 1 [ml]
Mass [mg]
0.00
10.00
3.53
10.00
8.29
9.00
0.69
7.50
5
0.29
6.00
0.000
0.035
0.075
0.005
= Reactor volume
Mass [mg]
3.09
1.10
0.46
0.01
0.02
Trap 2
eff. Conc [mg/l]
Trap Volume 2 [ml] Mass [mg]
0.00
10.00
6.19
10.00
7.47
9.00
0.73
7.50
0.002
0.35
0.00
0.06
0.07
0.01
6.00
0.00
%Diff
-4%
-5%
-5%
8%
-6%
2%
0%
2%
6%
-1%
%RSD
4.0%
3.7%
5.4%
1.4%
3.3%
4.0%
3.7%
5.4%
1.4%
3.3%
Trichloromethane
Results from the GC/MS analysis
Com ponent Nam e
Chloroform_83
Equation
Y = 203289+1.31021e+007*X R^2 = 0.9919
Standards
Sam ple Nam e Integ. Type
Area
Know Conc Calculated Conc
0.2_1
Method Settings
2724719
0.200
0.192
0.6_1
Method Settings
7697120
0.600
0.572
1_1
Method Settings
12587209
1.000
0.945
1.5_1
Method Settings
21483017
1.500
1.624
2_1
Method Settings
24927411
2.000
1.887
0.2_2
Method Settings
2872087
0.200
0.204
0.6_2
Method Settings
8101162
0.600
0.603
1_2
Method Settings
13568286
1.000
1.020
1.5_2
Method Settings
21062350
1.500
1.592
2_2
Method Settings
26095324
2.000
1.976
1_liquid
Method Settings
23047949
1.744
2_gas_1
Method Settings
59769114
4.546
2_gas_2
Method Settings
24211966
1.832
3_liquid
Manual Integration
8112257
0.604
4_gas_1
Method Settings
32993270
2.503
4_gas_2
Method Settings
20604044
1.557
5_liquid
Method Settings
2569779
0.181
6_gas_1
Method Settings
8001484
0.595
6_gas_2
Method Settings
8512421
0.634
6_gas_1_undil Method Settings
22441522
1.697
6_gas_2_undil Method Settings
18742915
1.415
7_liquid
Manual Integration
685425
0.037
8_gas_1
Method Settings
3095020
0.221
8_gas_2
Manual Integration
3235379
0.231
8_gas_1_undil Method Settings
12644959
0.950
8_gas_2_undil Method Settings
11482744
0.861
9_liquid
Method Settings
1202295
0.076
Dilusion
assume
high
Dillusion
Reactor
Trap 1
Trap 2
low
1
1
4
Average
1
4
8
10
Average
1.00
4
8
10
Average
best range
2
3
6.97
6.97
2.41
2.41
0.00
18.19
4
0.72
0.72
5
0.04
0.08
0.04
1.70
2.38
0.08
0.95
1.77
0.00
18.19
0.00
7.33
25.03
25.03
2.04
1.42
2.54
1.36
0.86
1.85
0.00
7.33
15.57
15.57
1.98
1.85
10
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Calculated concentrations and masses
Tim e vs Concentration, Mass
Sample Nr.
1
2
3
4
5
Sample Nr.
1
2
3
4
5
0.3
Reactor
Time since start [h] eff. Conc [mg/l]
0:00
6.97
1:30
2.41
4:15
0.72
24:00
0.04
46:00
0.08
Time
16.05.2012 12:15
16.05.2012 13:45
16.05.2012 16:30
17.05.2012 12:15
18.05.2012 10:15
Trap 1
eff. Conc [mg/l]
Trap Volume 1 [ml]
Mass [mg]
0.00
10.00
18.19
10.00
25.03
9.00
1.70
7.50
0.95
6.00
0.000
0.182
0.225
0.013
0.006
Mass [mg]
2.09
0.72
0.22
0.01
0.02
Trap 2
eff. Conc [mg/l]
Trap Volume 2 [ml] Mass [mg]
0.00
10.00
7.33
10.00
15.57
9.00
2.54
7.50
0.86
6.00
0.00
0.07
0.14
0.02
0.01
Tetrachloromethane
Results from the GC/MS analysis
Com ponent Nam e
Tetrachlormethan_117
Sam ple Nam e
0.2_1
0.6_1
1_1
1.5_1
2_1
0.2_2
0.6_2
1_2
1.5_2
2_2
1_liquid
2_gas_1
2_gas_2
3_liquid
4_gas_1
4_gas_2
5_liquid
6_gas_1
6_gas_2
6_gas_1_undil
6_gas_2_undil
7_liquid
8_gas_1
8_gas_2
8_gas_1_undil
8_gas_2_undil
9_liquid
Integ. Type
Manual Integration
Method Settings
Method Settings
Method Settings
Method Settings
Manual Integration
Method Settings
Manual Integration
Method Settings
Method Settings
Method Settings
Method Settings
Method Settings
Manual Integration
Method Settings
Method Settings
Manual Integration
Method Settings
Method Settings
Method Settings
Method Settings
Manual Integration
Method Settings
Manual Integration
Method Settings
Method Settings
Manual Integration
Equation
Y = -22843.6+1.6912e+007*X R^2 = 0.9983
Standards
Area
Know Conc
3163390
0.200
9791742
0.600
16385637
1.000
24876591
1.500
33092435
2.000
3459291
0.200
10349286
0.600
17462544
1.000
26231377
1.500
34203711
2.000
9307949
130260746
22265612
2453966
61092440
22390665
721202
14840734
18899678
61240555
74671649
74924
2610231
3767302
18785427
25974836
268187
Calculated Conc
0.188
0.580
0.970
1.472
1.958
0.206
0.613
1.034
1.552
2.024
0.552
7.704
1.318
0.146
3.614
1.325
0.044
0.879
1.119
3.622
4.417
0.006
0.156
0.224
1.112
1.537
0.017
%Diff
-6%
-3%
-3%
-2%
-2%
3%
2%
3%
3%
1%
%RSD
6.3%
3.9%
4.5%
3.7%
2.3%
6.3%
3.9%
4.5%
3.7%
2.3%
Dilution
assume
high
Dillusion
Reactor
Trap 1
Trap 2
low
1
1
4
Average
1
4
8
10
Average
1.00
4
8
10
Average
best range
2
3
2.21
2.21
0.59
0.59
0.00
30.81
4
0.18
0.18
5
0.01
0.02
0.01
3.62
3.52
0.02
1.11
1.25
0.00
30.81
0.00
5.27
36.14
36.14
3.57
4.42
4.48
1.18
1.54
1.79
0.00
5.27
13.25
13.25
4.48
1.79
11
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
1
2
3
4
5
Sample Nr.
1
2
3
4
5
5.2.
0.3
Reactor
Time since start [h] eff. Conc [mg/l]
0:00
2.21
1:30
0.59
4:15
0.18
24:00
0.01
46:00
0.02
Time
16.05.2012 12:15
16.05.2012 13:45
16.05.2012 16:30
17.05.2012 12:15
18.05.2012 10:15
Trap 1
eff. Conc [mg/l]
Trap Volume 1 [ml]
Mass [mg]
0.00
10.00
30.81
10.00
36.14
9.00
3.52
7.50
1.11
6.00
Mass [mg]
0.66
0.18
0.05
0.00
0.01
Trap 2
eff. Conc [mg/l]
0.000
0.308
0.325
0.026
0.007
0.00
5.27
13.25
4.48
1.79
Trap Volume 2 [ml] Mass [mg]
10.00
10.00
9.00
7.50
6.00
0.00
0.05
0.12
0.03
0.01
Experiment Blank_2
5.2.1. Data
Dichloromethane
Results from the GC/MS analysis
Com ponent Nam e
Dichlormethan_84
Sam ple Nam e
0.2_1
0.2_2
0.6_1
0.6_2
1_1
1_2
1.5_1
1.5_2
0_l_stern
0_l
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_l
4_ga
4_gb
5_l
5_ga_1
5_ga_2
5_gb_1
5_gb_2
6_l
6_ga
6_gb
7_l
7_ga
7_gb
7_ga_undil
7_gb_undil
8_l
8_ga
8_gb
8_ga_undil
8_gb_undil
Area
2660488
2686183
8097322
8242229
13595633
14233941
21675983
20825406
15261684
20148678
16016179
918435
616351
17334084
5566434
373841
16630528
9919846
1631345
18764387
11856448
654211
17808848
27113730
20213915
3564871
2660247
10251002
2300470
43369
Equation
Y = -202155+1.42177e+007*X R^2 = 0.9986
Standards
Know Conc Calculated Conc
0.200
0.201
0.200
0.203
0.600
0.584
0.600
0.594
1.000
0.970
1.000
1.015
1.500
1.539
1.500
1.479
1.088
1.431
1.141
0.079
0.058
1.233
0.406
0.041
1.184
0.712
0.129
1.334
0.848
0.060
1.267
1.921
1.436
0.265
0.201
N/A
0.000
0.735
0.176
0.000
N/A
0.000
N/A
0.000
N/A
0.000
N/A
0.000
N/A
0.000
N/A
0.000
N/A
0.000
N/A
0.000
N/A
0.000
%Diff
1%
2%
-3%
-1%
-3%
2%
3%
-1%
%RSD
0.6%
0.6%
1.2%
1.2%
3.2%
3.2%
2.8%
2.8%
repeat
repeat
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
12
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Dilution
assume
high
DILLUSION
Dillusion factor
Reactor
Trap 1
Trap 2
low
0
1
2
Average
1
2
5
Average
1
2
5
Average
2.86
2.86
0.00
Trap 2
2
3
2.281
2.28
4
2.467
2.47
2.368
2.37
2.668
2.67
3.560
3.56
4.241
4.24
4.241
4.24
0.20
0.20
0.64
0.64
0.30
0.30
0.16
0.00
0.00
0.16
0.12
0.00
assume
high
DILLUSION
Dillusion factor
Reactor
Trap 1
best range
1
0.12
low
5
1
2
Average
1
2
5
Average
1
2
5
Average
best range
6
7
8
1.267
0.000
0.000
0.000
1.267
0.000
0.000
0.000
0.000
0.000
0.000
0.000
7.180
7.180
0.880
0.880
0.000
0.000
0.000
0.000
0.000
0.000
1.007
1.007
0.880
0.880
0.000
0.000
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
0
1
2
3
4
5
6
7
8
Time
23.05.2012 12:50
23.05.2012 13:00
23.05.2012 13:30
23.05.2012 14:30
23.05.2012 15:30
23.05.2012 16:30
23.05.2012 17:30
23.05.2012 18:30
24.05.2012 09:00
24.05.2012 13:30
Tim e vs Concentration, Mass
Trap 1
Sample Nr.
eff. Conc [mg/l]
0
1
2
3
4
5
6
7
8
0.00
0.16
3.56
4.24
4.24
7.18
0.88
0.00
0.00
0.3
Reactor
Time since start [h] eff. Conc [mg/l]
0:00
1.09
0:10
2.86
0:40
2.28
1:40
2.47
2:40
2.37
3:40
2.67
4:40
1.27
5:40
0.00
20:10
0.00
24:40
0.00
Trap Volume 1 [ml]
Mass [mg]
12.00
12.00
11.50
11.00
10.20
9.50
8.00
7.00
6.00
5.00
Mass [mg]
0.33
0.86
0.68
0.74
0.71
0.80
0.38
0.00
0.00
0.00
Trap 2
eff. Conc [mg/l]
0.00
0.00
0.04
0.04
0.04
0.06
0.01
0.00
0.00
0.00
0.12
0.20
0.64
0.30
1.01
0.88
0.00
0.00
Trap Volume 2 [ml] Mass [mg]
12.00
12.00
11.50
11.00
10.20
9.50
8.00
7.00
6.00
5.00
0.00
0.00
0.00
0.01
0.00
0.01
0.01
0.00
0.00
13
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Trichloromethane
Results from the GC/MS analysis
Com ponent Nam
Equation
Chloroform_83 Y = -176613+2.42085e+007*X R^2 = 0.9996
Standards
Sam ple Nam e
Area
Know Conc Calculated Conc
0.2_1
4490077
0.200
0.193
0.2_2
4686470
0.200
0.201
0.6_1
14446361
0.600
0.604
0.6_2
14355588
0.600
0.600
1_1
23442586
1.000
0.976
1_2
24301914
1.000
1.011
1.5_1
36325226
1.500
1.508
1.5_2
36138472
1.500
1.500
0_l_stern
20027481
0.835
0_l
21772328
0.907
1_l
12767818
0.535
1_ga
2159475
0.096
1_gb
995424
0.048
2_l
8928329
0.376
2_ga
8102896
0.342
2_gb
492577
0.028
3_l
6380712
0.271
3_ga
12969956
0.543
3_gb
1385257
0.065
4_l
5119978
0.219
4_ga
13837803
0.579
4_gb
300068
0.020
5_l
3657039
0.158
5_ga_1
22690041
0.945
5_ga_2
20373717
0.849
5_gb_1
1251756
0.059
5_gb_2
1053785
0.051
6_l
N/A
0.000
6_ga
6878317
0.291
6_gb
636558
0.034
7_l
118077
0.012
7_ga
N/A
0.000
7_gb
N/A
0.000
7_ga_undil
N/A
0.000
7_gb_undil
N/A
0.000
8_l
N/A
0.000
8_ga
N/A
0.000
8_gb
N/A
0.000
8_ga_undil
N/A
0.000
8_gb_undil
N/A
0.000
%Diff
-4%
0%
1%
0%
-2%
1%
1%
0%
%RSD
2.9%
2.9%
0.4%
0.4%
2.5%
2.5%
0.4%
0.4%
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Dilution
assume
high
DILLUSION
Sample Nr.
Reactor
Trap 1
Trap 2
1
2
Average
1
2
5
Average
1
2
5
Average
low
0
best range
1
1.81
1.81
0.00
2
1.069
1.07
3
4
0.752
0.75
0.542
0.54
0.438
0.44
2.715
2.72
2.895
2.89
2.895
2.89
0.14
0.14
0.32
0.32
0.10
0.10
0.19
0.00
0.00
0.19
0.10
0.00
0.10
14
Appendix: Formation of chlorinated organics during electrolytic urine treatment
assume
high
DILLUSION
Dillusion factor
Reactor
Trap 1
Trap 2
low
5
1
2
Average
1
2
5
Average
1
2
5
Average
best range
6
7
8
0.158
0.000
0.000
0.000
0.158
0.000
0.000
0.000
0.000
0.000
0.000
0.000
4.723
4.723
0.168
0.168
0.000
0.000
0.000
0.000
0.000
0.000
0.295
0.295
0.168
0.168
0.000
0.000
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
0
1
2
3
4
5
6
7
8
Time
23.05.2012 12:50
23.05.2012 13:00
23.05.2012 13:30
23.05.2012 14:30
23.05.2012 15:30
23.05.2012 16:30
23.05.2012 17:30
23.05.2012 18:30
24.05.2012 09:00
24.05.2012 13:30
Tim e vs Concentration, Mass
Trap 1
Sample Nr.
eff. Conc [mg/l]
0
1
2
3
4
5
6
7
8
0.00
0.19
2.72
2.89
2.89
4.72
0.17
0.00
0.00
0.3
Reactor
Time since start [h] eff. Conc [mg/l]
0:00
0.83
0:10
1.81
0:40
1.07
1:40
0.75
2:40
0.54
3:40
0.44
4:40
0.16
5:40
0.00
20:10
0.00
24:40
0.00
Trap Volume 1 [ml]
Mass [mg]
12.00
12.00
11.50
11.00
10.20
9.50
8.00
7.00
6.00
5.00
Mass [mg]
0.25
0.54
0.32
0.23
0.16
0.13
0.05
0.00
0.00
0.00
Trap 2
eff. Conc [mg/l]
0.00
0.00
0.03
0.03
0.03
0.04
0.00
0.00
0.00
0.00
0.10
0.14
0.32
0.10
0.30
0.17
0.00
0.00
Trap Volume 2 [ml] Mass [mg]
12.00
12.00
11.50
11.00
10.20
9.50
8.00
7.00
6.00
5.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
15
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Tretrachloromethane
Results from the GC/MS analysis
Com ponent Nam e
Tetrachlormethan_117
Sam ple Nam e
0.2_1
0.2_2
0.6_1
0.6_2
1_1
1_2
1.5_1
1.5_2
0_l_stern
0_l
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_l
4_ga
4_gb
5_l
5_ga_1
5_ga_2
5_gb_1
5_gb_2
6_l
6_ga
6_gb
7_l
7_ga
7_gb
7_ga_undil
7_gb_undil
8_l
8_ga
8_gb
8_ga_undil
8_gb_undil
Area
3240814
3421884
10900806
10679081
17679556
18390391
27281995
27343544
9462315
7465036
3573429
6983604
480490
1771110
19276027
326965
1055075
30670557
651477
654446
33371639
393200
423559
45800124
42993003
1441729
1347836
15105677
795251
Equation
Y = -219407+1.83201e+007*X R^2 = 0.9995
Standards
Know Conc Calculated Conc
0.200
0.189
0.200
0.199
0.600
0.607
0.600
0.595
1.000
0.977
1.000
1.016
1.500
1.501
1.500
1.505
0.528
0.419
0.207
0.393
0.038
0.109
1.064
0.030
0.070
1.686
0.048
0.048
1.834
0.033
0.035
2.512
2.359
0.091
0.086
N/A
0.000
0.837
0.055
N/A
0.000
N/A
0.000
N/A
0.000
N/A
0.000
N/A
0.000
N/A
0.000
N/A
0.000
N/A
0.000
N/A
0.000
N/A
0.000
%Diff
-6%
-1%
1%
-1%
-2%
2%
0%
0%
%RSD
3.6%
3.6%
1.4%
1.4%
2.8%
2.8%
0.2%
0.2%
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Dilution
assume
high
DILLUSION
Sample Nr.
Reactor
Trap 1
Trap 2
1
2
Average
1
2
5
Average
1
2
5
Average
low
0
best range
1
0.84
0.84
0.00
2
0.414
0.41
3
4
0.217
0.22
0.139
0.14
0.095
0.10
8.431
8.43
9.168
9.17
9.168
9.17
0.15
0.15
0.24
0.24
0.17
0.17
0.79
0.00
0.00
0.79
0.08
0.00
0.08
16
Appendix: Formation of chlorinated organics during electrolytic urine treatment
assume
high
DILLUSION
Dillusion factor
Reactor
Trap 1
Trap 2
low
5
1
2
Average
1
2
5
Average
1
2
5
Average
best range
6
7
8
0.035
0.000
0.000
0.000
0.035
0.000
0.000
0.000
0.000
0.000
0.000
0.000
11.794
11.794
0.277
0.277
0.000
0.000
0.000
0.000
0.000
0.000
0.453
0.453
0.277
0.277
0.000
0.000
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
0
1
2
3
4
5
6
7
8
Time
23.05.2012 12:50
23.05.2012 13:00
23.05.2012 13:30
23.05.2012 14:30
23.05.2012 15:30
23.05.2012 16:30
23.05.2012 17:30
23.05.2012 18:30
24.05.2012 09:00
24.05.2012 13:30
Tim e vs Concentration, Mass
Trap 1
Sample Nr.
eff. Conc [mg/l]
0
1
2
3
4
5
6
7
8
0.00
0.79
8.43
9.17
9.17
11.79
0.28
0.00
0.00
0.3
Reactor
Time since start [h] eff. Conc [mg/l]
0:00
0.53
0:10
0.84
0:40
0.41
1:40
0.22
2:40
0.14
3:40
0.10
4:40
0.04
5:40
0.00
20:10
0.00
24:40
0.00
Trap Volume 1 [ml]
Mass [mg]
12.00
12.00
11.50
11.00
10.20
9.50
8.00
7.00
6.00
5.00
Mass [mg]
0.16
0.25
0.12
0.07
0.04
0.03
0.01
0.00
0.00
0.00
Trap 2
eff. Conc [mg/l]
0.00
0.01
0.09
0.09
0.09
0.09
0.00
0.00
0.00
0.00
0.08
0.15
0.24
0.17
0.45
0.28
0.00
0.00
Trap Volume 2 [ml] Mass [mg]
12.00
12.00
11.50
11.00
10.20
9.50
8.00
7.00
6.00
5.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
17
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Chlorobenzene
Results from the GC/MS analysis
Com ponent Nam e
Chlorbenzol_112
Sam ple Nam e
0.2_1
0.2_2
0.6_1
0.6_2
1_1
1_2
1.5_1
1.5_2
0_l_stern
0_l
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_l
4_ga
4_gb
5_l
5_ga_1
5_ga_2
5_gb_1
5_gb_2
6_l
6_ga
6_gb
7_l
7_ga
7_gb
7_ga_undil
7_gb_undil
8_l
8_ga
8_gb
8_ga_undil
8_gb_undil
Area
6831617
7067356
21827964
21789860
36024677
36660630
55507755
56059667
19332014
108606377
107558589
1617523
1247327
10880214
126832798
120421808
129673694
393825583
422580954
1109066707
134412406
128072200
395336717
473858583
621688872
2350985
397959
38671
160498087
25255495
86085531
Equation
Y = -469566+3.72721e+007*X R^2 = 0.9996
Standards
Know Conc Calculated Conc
0.200
0.196
0.200
0.202
0.600
0.598
0.600
0.597
1.000
0.979
1.000
0.996
1.500
1.502
1.500
1.517
0.531
2.926
2.898
0.056
0.046
3.015
N/A
0.000
N/A
0.000
3.243
3.492
10.579
11.350
29.769
3.619
3.449
10.619
12.726
16.692
0.076
N/A
0.000
0.023
0.014
N/A
0.000
N/A
0.000
N/A
0.000
N/A
0.000
0.000
N/A
0.000
N/A
0.000
0.690
N/A
0.000
0.000
%Diff
-2%
1%
0%
0%
-2%
0%
0%
1%
%RSD
2.2%
2.2%
0.1%
0.1%
1.2%
1.2%
0.7%
0.7%
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Dilution
assume
high
DILLUSION
Sample Nr.
Reactor
Trap 1
Trap 2
1
2
Average
1
2
5
Average
1
2
5
Average
low
0
best range
1
5.85
5.85
0.00
2
5.797
5.80
3
4
6.030
6.03
6.487
6.49
22.701
22.70
17.459
17.46
148.843
148.84
148.843
148.84
0.00
0.00
52.89
52.89
18.09
18.09
0.11
0.00
0.00
0.11
0.09
0.00
0.09
18
Appendix: Formation of chlorinated organics during electrolytic urine treatment
assume
high
DILLUSION
Dillusion factor
Reactor
Trap 1
Trap 2
low
5
1
2
Average
1
2
5
Average
1
2
5
Average
best range
6
7
8
3.449
0.000
0.000
0.000
3.449
0.000
0.000
0.000
0.000
0.000
0.000
0.000
63.631
63.631
0.068
0.068
0.000
0.000
0.000
0.000
0.000
1.380
83.462
83.462
0.068
0.068
0.000
0.690
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
0
1
2
3
4
5
6
7
8
Time
23.05.2012 12:50
23.05.2012 13:00
23.05.2012 13:30
23.05.2012 14:30
23.05.2012 15:30
23.05.2012 16:30
23.05.2012 17:30
23.05.2012 18:30
24.05.2012 09:00
24.05.2012 13:30
Tim e vs Concentration, Mass
Trap 1
Sample Nr.
eff. Conc [mg/l]
0
1
2
3
4
5
6
7
8
0.00
0.11
17.46
148.84
148.84
63.63
0.07
0.00
0.00
0.3
Reactor
Time since start [h] eff. Conc [mg/l]
0:00
0.53
0:10
5.85
0:40
5.80
1:40
6.03
2:40
6.49
3:40
22.70
4:40
3.45
5:40
0.00
20:10
0.00
24:40
0.00
Trap Volume 1 [ml]
Mass [mg]
12.00
12.00
11.50
11.00
10.20
9.50
8.00
7.00
6.00
5.00
Mass [mg]
0.16
1.76
1.74
1.81
1.95
6.81
1.03
0.00
0.00
0.00
Trap 2
eff. Conc [mg/l]
0.00
0.00
0.19
1.52
1.41
0.51
0.00
0.00
0.00
0.00
0.09
0.00
52.89
18.09
83.46
0.07
0.00
0.69
Trap Volume 2 [ml] Mass [mg]
12.00
12.00
11.50
11.00
10.20
9.50
8.00
7.00
6.00
5.00
0.00
0.00
0.00
0.54
0.17
0.67
0.00
0.00
0.00
19
Appendix: Formation of chlorinated organics during electrolytic urine treatment
5.3.
Experiment Air_1
5.3.1. Data
No dillusion was made in Air_1 because it was not known what concentration had to be
expected.
Dichloromethane
Results from the GC/MS analysis
Com ponent Nam e
Dichlormethan_84
Sam ple Nam e
0_2
0_6
1_0
1_5
0_l
0_ga
0_gb
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_l
4_ga
4_gb
5_l
5_ga
5_gb
6_l
6_ga
6_gb
7_l
7_ga
7_gb
8_l
8_ga
8_gb
9_l
9_ga
9_gb
10_l
10_ga
10_gb
11_l
11_ga
11_gb
12_l
12_ga
12_gb
Area
776617
2190583
3404261
5461675
408568
397134
383868
10285587
403186
229219
6052042
405843
243861
7845801
512560
229229
5219237
567817
210554
5067552
802601
204281
5882530
1144221
246981
1921868
334519
2368837
263579
3723270
322403
4724433
329399
10699425
2134525
11665458
2674523
Equation
Y = 9738.11+3.57104e+006*X R^2 = 0.9976
Standards
Know Conc Calculated Conc
0.200
0.215
0.600
0.611
1.000
0.951
1.500
1.527
0.112
0.108
0.105
2.878
0.110
0.061
1.692
0.111
0.066
2.194
0.141
0.061
1.459
0.156
0.056
1.416
0.222
0.054
1.645
0.318
0.066
N/A
0.000
0.535
0.091
N/A
0.000
0.661
0.071
N/A
0.000
1.040
0.088
N/A
0.000
1.320
0.090
N/A
0.000
2.993
0.595
N/A
0.000
3.264
0.746
%Diff
7%
2%
-5%
2%
%RSD
0.0%
0.0%
0.0%
0.0%
N/A
N/A
N/A
N/A
N/A
N/A
20
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
0
1
2
3
4
5
6
7
8
9
10
11
12
Time
20.06.2012 10:45
20.06.2012 10:50
20.06.2012 11:10
20.06.2012 11:30
20.06.2012 11:45
20.06.2012 12:15
20.06.2012 12:45
20.06.2012 13:45
20.06.2012 14:45
20.06.2012 15:45
20.06.2012 17:45
21.06.2012 09:00
21.06.2012 14:30
0.3
Reactor
Time since start [h] eff. Conc [mg/l]
0:00
0.11
0:05
5.76
0:25
3.38
0:45
4.39
1:00
2.92
1:30
2.83
2:00
3.29
3:00
0.00
4:00
0.00
5:00
0.00
7:00
0.00
22:15
0.00
27:45
0.00
Tim e vs Concentration, Mass
Trap 1
Sample Nr.
eff. Conc [mg/l]
Trap Volume 1 [l]
Mass [mg]
0
0.11
0.10
1
0.11
0.09
2
0.11
0.09
3
0.14
0.09
4
0.16
0.09
5
0.22
0.09
6
0.32
0.08
7
0.54
0.08
8
0.66
0.07
9
1.04
0.07
10
1.32
0.07
11
2.99
0.07
12
3.26
0.07
0.01
0.01
0.01
0.01
0.01
0.02
0.03
0.04
0.05
0.08
0.10
0.21
0.23
Mass [mg]
0.03
1.73
1.02
1.32
0.88
0.85
0.99
0.00
0.00
0.00
0.00
0.00
0.00
Trap 2
eff. Conc [mg/l]
Trap Volume 1 [l] Mass [mg]
0.10
0.10
0.06
0.09
0.07
0.09
0.06
0.09
0.06
0.09
0.05
0.09
0.07
0.08
0.09
0.08
0.07
0.08
0.09
0.08
0.09
0.07
0.60
0.07
0.75
0.07
0.01
0.01
0.01
0.01
0.00
0.00
0.01
0.01
0.01
0.01
0.01
0.04
0.05
21
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Trichloromethane
Results from the GC/MS analysis
Com ponent Nam e
Chloroform_83
Sam ple Nam e
0_2
0_6
1_0
1_5
0_l
0_ga
0_gb
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_l
4_ga
4_gb
5_l
5_ga
5_gb
6_l
6_ga
6_gb
7_l
7_ga
7_gb
8_l
8_ga
8_gb
9_l
9_ga
9_gb
10_l
10_ga
10_gb
11_l
11_ga
11_gb
12_l
12_ga
12_gb
Area
1174672
3018724
5133757
8500543
305708
95343
292682
15883413
99942
63422
9469606
88921
62282
12001997
275195
190867
7538496
500087
66095
7376021
1085307
60766
8602459
1778023
61975
3923789
220111
5287205
91898
9409076
132688
11577668
197923
28998420
2044369
322251
32350316
2689606
Equation
Y = -95156.4+5.54651e+006*X R^2 = 0.9943
Standards
Know Conc Calculated Conc
0.200
0.229
0.600
0.561
1.000
0.943
1.500
1.550
0.072
0.034
0.070
2.881
0.035
0.029
1.724
0.033
0.028
2.181
0.067
0.052
1.376
0.107
0.029
1.347
0.213
0.028
1.568
0.338
0.028
N/A
0.000
0.725
0.057
N/A
0.000
0.970
0.034
N/A
0.000
1.714
0.041
N/A
0.000
2.105
0.053
N/A
0.000
5.245
0.386
0.075
5.850
0.502
%Diff
14%
-6%
-6%
3%
%RSD
0.0%
0.0%
0.0%
0.0%
N/A
N/A
N/A
N/A
N/A
22
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
0
1
2
3
4
5
6
7
8
9
10
11
12
Time
20.06.2012 10:45
20.06.2012 10:50
20.06.2012 11:10
20.06.2012 11:30
20.06.2012 11:45
20.06.2012 12:15
20.06.2012 12:45
20.06.2012 13:45
20.06.2012 14:45
20.06.2012 15:45
20.06.2012 17:45
21.06.2012 09:00
21.06.2012 14:30
0.3
Reactor
Time since start [h] eff. Conc [mg/l]
0:00
0.07
0:05
5.76
0:25
3.45
0:45
4.36
1:00
2.75
1:30
2.69
2:00
3.14
3:00
0.00
4:00
0.00
5:00
0.00
7:00
0.00
22:15
0.00
27:45
0.08
Tim e vs Concentration, Mass
Trap 1
Sample Nr.
eff. Conc [mg/l]
Trap Volume 1 [l]
Mass [mg]
0
0.03
0.10
1
0.04
0.09
2
0.03
0.09
3
0.07
0.09
4
0.11
0.09
5
0.21
0.09
6
0.34
0.08
7
0.72
0.08
8
0.97
0.07
9
1.71
0.07
10
2.10
0.07
11
5.25
0.07
12
5.85
0.07
0.00
0.00
0.00
0.01
0.01
0.02
0.03
0.06
0.07
0.13
0.15
0.37
0.41
Mass [mg]
0.02
1.73
1.03
1.31
0.83
0.81
0.94
0.00
0.00
0.00
0.00
0.00
0.02
Trap 2
eff. Conc [mg/l]
Trap Volume 1 [l] Mass [mg]
0.07
0.10
0.03
0.09
0.03
0.09
0.05
0.09
0.03
0.09
0.03
0.09
0.03
0.08
0.06
0.08
0.03
0.08
0.04
0.08
0.05
0.07
0.39
0.07
0.50
0.07
0.01
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.03
0.04
23
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Tretrachloromethane
Results from the GC/MS analysis
Com ponent Nam e
Tetrachlormethan_117
Sam ple Nam e
0_2
0_6
1_0
1_5
0_l
0_ga
0_gb
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_l
4_ga
4_gb
5_l
5_ga
5_gb
6_l
6_ga
6_gb
7_l
7_ga
7_gb
8_l
8_ga
8_gb
9_l
9_ga
9_gb
10_l
10_ga
10_gb
11_l
11_ga
11_gb
12_l
12_ga
12_gb
Area
1097836
2762697
4628716
7156611
315148
272687
10953601
5567716
6195357
75914
100679
3288881
411932
2660244
1397990
2801760
2947721
6475457
113975
10198491
8333
12712233
36543
12892173
86777
19907131
739348
20802752
969338
Equation
Y = 28897.9+4.69738e+006*X R^2 = 0.9987
Standards
Know Conc Calculated Conc
0.200
0.228
0.600
0.582
1.000
0.979
1.500
1.517
0.061
N/A
0.000
0.052
2.326
N/A
0.000
N/A
0.000
1.179
N/A
0.000
N/A
0.000
1.313
0.010
0.015
0.694
0.082
N/A
0.000
0.560
0.291
N/A
0.000
0.590
0.621
N/A
0.000
N/A
0.000
1.372
0.018
N/A
0.000
2.165
0.000
N/A
0.000
2.700
0.002
N/A
0.000
2.738
0.012
N/A
0.000
4.232
0.151
N/A
0.000
4.422
0.200
%Diff
14%
-3%
-2%
1%
%RSD
0.0%
0.0%
0.0%
0.0%
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
24
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
0
1
2
3
4
5
6
7
8
9
10
11
12
Time
20.06.2012 10:45
20.06.2012 10:50
20.06.2012 11:10
20.06.2012 11:30
20.06.2012 11:45
20.06.2012 12:15
20.06.2012 12:45
20.06.2012 13:45
20.06.2012 14:45
20.06.2012 15:45
20.06.2012 17:45
21.06.2012 09:00
21.06.2012 14:30
0.3
Reactor
Time since start [h] eff. Conc [mg/l]
0:00
0.06
0:05
4.65
0:25
2.36
0:45
2.63
1:00
1.39
1:30
1.12
2:00
1.18
3:00
0.00
4:00
0.00
5:00
0.00
7:00
0.00
22:15
0.00
27:45
0.00
Tim e vs Concentration, Mass
Trap 1
Sample Nr.
eff. Conc [mg/l]
Trap Volume 1 [l]
Mass [mg]
0
0.00
0.10
1
0.00
0.09
2
0.00
0.09
3
0.01
0.09
4
0.08
0.09
5
0.29
0.09
6
0.62
0.08
7
1.37
0.08
8
2.16
0.07
9
2.70
0.07
10
2.74
0.07
11
4.23
0.07
12
4.42
0.07
0.00
0.00
0.00
0.00
0.01
0.03
0.05
0.10
0.16
0.20
0.20
0.30
0.31
Mass [mg]
0.02
1.40
0.71
0.79
0.42
0.34
0.35
0.00
0.00
0.00
0.00
0.00
0.00
Trap 2
eff. Conc [mg/l]
Trap Volume 1 [l] Mass [mg]
0.05
0.10
0.00
0.09
0.00
0.09
0.02
0.09
0.00
0.09
0.00
0.09
0.00
0.08
0.02
0.08
0.00
0.08
0.00
0.08
0.01
0.07
0.15
0.07
0.20
0.07
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.01
0.01
25
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Chlorobenzene
Results from the GC/MS analysis
Com ponent Nam e
Chlorbenzol_112
Sam ple Nam e
0_2
0_6
1_0
1_5
0_l
0_ga
0_gb
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_l
4_ga
4_gb
5_l
5_ga
5_gb
6_l
6_ga
6_gb
7_l
7_ga
7_gb
8_l
8_ga
8_gb
9_l
9_ga
9_gb
10_l
10_ga
10_gb
11_l
11_ga
11_gb
12_l
12_ga
12_gb
Area
1422885
3995976
7041164
11159719
170051
30314859
17169147
21585465
13153361
157773
12011261
393752
12791603
1785851
85126
2107487
4718223
6254176
5761566
16395230
90045
20185741
169938
Equation
Y = -151566+7.38714e+006*X R^2 = 0.9975
Standards
Know Conc Calculated Conc
0.200
0.213
0.600
0.561
1.000
0.974
1.500
1.531
0.044
N/A
0.000
N/A
0.000
4.124
N/A
0.000
N/A
0.000
2.345
N/A
0.000
N/A
0.000
2.943
N/A
0.000
N/A
0.000
1.801
0.042
N/A
0.000
1.646
0.074
N/A
0.000
1.752
0.262
N/A
0.000
0.032
0.306
N/A
0.000
N/A
0.000
0.659
N/A
0.000
N/A
0.000
0.867
N/A
0.000
N/A
0.000
0.800
N/A
0.000
N/A
0.000
2.240
0.033
N/A
0.000
2.753
0.044
%Diff
7%
-6%
-3%
2%
%RSD
0.0%
0.0%
0.0%
0.0%
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
26
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
0
1
2
3
4
5
6
7
8
9
10
11
12
Time
20.06.2012 10:45
20.06.2012 10:50
20.06.2012 11:10
20.06.2012 11:30
20.06.2012 11:45
20.06.2012 12:15
20.06.2012 12:45
20.06.2012 13:45
20.06.2012 14:45
20.06.2012 15:45
20.06.2012 17:45
21.06.2012 09:00
21.06.2012 14:30
0.3
Reactor
Time since start [h] eff. Conc [mg/l]
0:00
0.04
0:05
8.25
0:25
4.69
0:45
5.89
1:00
3.60
1:30
3.29
2:00
3.50
3:00
0.03
4:00
0.00
5:00
0.00
7:00
0.00
22:15
0.00
27:45
0.00
Tim e vs Concentration, Mass
Trap 1
Sample Nr.
eff. Conc [mg/l]
Trap Volume 1 [l]
Mass [mg]
0
0.00
0.10
1
0.00
0.09
2
0.00
0.09
3
0.00
0.09
4
0.04
0.09
5
0.07
0.09
6
0.26
0.08
7
0.31
0.08
8
0.66
0.07
9
0.87
0.07
10
0.80
0.07
11
2.24
0.07
12
2.75
0.07
0.00
0.00
0.00
0.00
0.00
0.01
0.02
0.02
0.05
0.06
0.06
0.16
0.19
Mass [mg]
0.01
2.47
1.41
1.77
1.08
0.99
1.05
0.01
0.00
0.00
0.00
0.00
0.00
Trap 2
eff. Conc [mg/l]
Trap Volume 1 [l] Mass [mg]
0.00
0.10
0.00
0.09
0.00
0.09
0.00
0.09
0.00
0.09
0.00
0.09
0.00
0.08
0.00
0.08
0.00
0.08
0.00
0.08
0.00
0.07
0.03
0.07
0.04
0.07
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
5.3.2. Concentration changing with time: Graph
Figure 6: Experiment Air_1. Concentration of chlorinated organics at three different places in the system
changing with time. 1.2mg/l of chlorinated organics spiked into a reactor of 300ml distilled water. No current
applied, turbulence generated with a high turbulence magnetic stirrer. Evolving gas sucked through two traps of
82ml dodecane each (0.78/h). Data points with gray box: concentration lower than calibration range.
The high variation in the concentration values of the samples in the reactor are due to the
fact, that the times for the extraction steps were not defined. From this experiment on the
procedure was unitary: After adding 1ml of sample and 1ml of dodecane, the sample was
shaken for 10 seconds and then let stand for 15 minutes before the dodecane phase (which
is above the water phase) was transferred to the GC vial. The values in gray are below the
calibration range and are assumed to be zero. The values in orange are above the
calibration range and might be underestimated.
27
Appendix: Formation of chlorinated organics during electrolytic urine treatment
5.4.
Experiment Air_2
5.4.1. Data
Dichloromethane
Results from the GC/MS analysis
Com ponent Nam e
Dichlormethan_84
Sam ple Nam e
0_2
0_6
1_0
1_5
1_L
1_GA
1_GB
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_ga_1
4_ga_2
4_gb
5_l
5_ga_1
5_ga_2
5_gb
6_ga_1
6_ga_2
6_gb
7_ga_1
7_ga_2
7_ga_4
7_gb
8_l
8_ga_2
8_ga_5
8_gb_1
8_gb_2
9_ga_2
9_ga_5
9_gb_2
9_gb_4
10_ga_2
10_ga_5
10_gb_2
10_gb_4
Area
887474
2186633
3193170
4883108
4939904
1633051
748671
4786257
474174
203370
3955747
341124
117167
616528
361661
81591
5388150
754509
444053
92789
950730
565879
98374
1274075
654259
332788
97776
5511066
953224
417631
119662
117184
3172429
1147862
304442
203320
3688959
1386119
372668
237978
Equation
Y = 146032+3.15764e+006*X R^2 = 0.9955
Standards
Know Conc Calculated Conc
0.200
0.235
0.600
0.646
1.000
0.965
1.500
1.500
1.518
0.471
0.191
1.470
0.104
0.018
1.207
0.062
0.000
0.149
0.068
0.000
1.660
0.193
0.094
0.000
0.255
0.133
0.000
0.357
0.161
0.059
0.000
1.699
0.256
0.086
0.000
0.000
0.958
0.317
0.050
0.018
1.122
0.393
0.072
0.029
%Diff
17%
8%
-3%
0%
%RSD
0.0%
0.0%
0.0%
0.0%
28
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Dilution
Dillusion - effective concentration [m g/l]
Dillusion
1
Reaktor
1
2
2.5
Average
Trap 1
1
2
4
5
Average
Trap 2
1
2
4
Average
assume
high
low
Dillusion
Reaktor
Trap 1
Trap 2
2
4
5
1.66
2.94
2.41
3.80
3.80
0.47
2.94
0.10
2.41
0.06
0.47
0.19
0.10
0.02
0.02
0.19
0.15
0.14
1.66
0.19
0.19
0.06
0.00
0.14
0.00
0.19
0.00
0.00
0.00
0.00
best range
6
1
2
2.5
Average
1
2
4
5
Average
1
2
4
Average
3
7
8
9
10
1.70
1.70
0.25
0.27
0.36
0.32
0.24
0.26
0.00
0.34
0.00
0.00
0.00
0.51
1.92
2.24
0.43
0.51
0.00
1.59
1.75
1.96
2.10
0.10
0.07
0.09
0.14
0.12
0.13
0.00
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
0
1
2
3
4
5
6
7
8
9
10
Time
29.06.2012 10:30
29.06.2012 10:35
29.06.2012 11:00
29.06.2012 11:30
29.06.2012 12:30
29.06.2012 13:30
29.06.2012 14:30
29.06.2012 15:30
29.06.2012 17:00
30.06.2012 09:00
30.06.2012 14:00
Time since start [h]
0:00
0:05
0:30
1:00
2:00
3:00
4:00
5:00
6:30
22:30
27:30
0.3
Reactor
eff. Conc [mg/l]
Tim e vs Concentration, Mass
Trap 1
Sample Nr.
eff. Conc [mg/l]
Trap Volume 1 [ml]
Mass [mg]
0
0.00
82.00
1
0.47
78.72
2
0.10
78.72
3
0.06
77.08
4
0.14
74.62
5
0.19
72.98
6
0.26
70.52
7
0.34
68.06
8
0.51
66.42
9
1.75
64.78
10
2.10
62.32
0.00
0.04
0.01
0.00
0.01
0.01
0.02
0.02
0.03
0.11
0.13
Mass [mg]
0
3.80
2.94
2.41
0.00
1.14
0.88
0.72
1.66
0.50
1.70
0.51
Trap 2
eff. Conc [mg/l]
Trap Volume 1 [ml] Mass [mg]
0.00
82.00
0.19
78.75
0.02
78.75
0.00
77.13
0.00
75.50
0.00
73.07
0.00
71.45
0.00
69.01
0.00
67.39
0.09
65.76
0.13
63.33
0.00
0.02
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.01
0.01
29
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Trichloromethane
Results from the GC/MS analysis
Com ponent Nam e
Chloroform_83
Sam ple Nam e
0_2
0_6
1_0
1_5
1_L
1_GA
1_GB
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_ga_1
4_ga_2
4_gb
5_l
5_ga_1
5_ga_2
5_gb
6_ga_1
6_ga_2
6_gb
7_ga_1
7_ga_2
7_ga_4
7_gb
8_l
8_ga_2
8_ga_5
8_gb_1
8_gb_2
9_ga_2
9_ga_5
9_gb_2
9_gb_4
10_ga_2
10_ga_5
10_gb_2
10_gb_4
Area
1538315
4138569
6615744
9706104
5640776
1061607
367775
5842214
413704
99358
4911727
378129
62587
806410
446725
49740
6477931
1422018
702117
52377
1957345
1006537
54731
2641239
1317534
622587
58520
6414455
2000581
750591
72975
51347
7261120
2653426
228648
131789
8610459
3344315
297475
169283
Equation
Y = 164205+6.41749e+006*X R^2 = 0.9990
Standards
Know Conc Calculated Conc
0.200
0.214
0.600
0.619
1.000
1.005
1.500
1.487
0.853
0.140
0.032
0.885
0.039
0.000
0.740
0.033
0.000
0.100
0.044
0.000
0.984
0.196
0.084
0.000
0.279
0.131
0.000
0.386
0.180
0.071
0.000
0.974
0.286
0.091
0.000
0.000
1.106
0.388
0.010
0.000
1.316
0.496
0.021
0.001
%Diff
7%
3%
1%
-1%
%RSD
0.0%
0.0%
0.0%
0.0%
Dilution
Dillusion - effective concentration [m g/l]
Dillusion
1
Reaktor
1
2
2.5
Average
Trap 1
1
2
4
5
Average
Trap 2
1
2
4
Average
assume
high
2
3
4
5
0.98
1.77
1.48
2.13
2.13
0.14
1.77
0.04
1.48
0.03
0.14
0.03
0.04
0.00
0.03
0.00
low
0.10
0.09
0.98
0.20
0.17
0.03
0.00
0.09
0.00
0.18
0.00
0.00
0.00
0.00
best range
30
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Dillusion
Reaktor
Trap 1
Trap 2
6
1
2
2.5
Average
1
2
4
5
Average
1
2
4
Average
7
8
9
10
0.97
0.97
0.28
0.26
0.39
0.36
0.29
0.27
0.00
0.37
0.00
0.00
0.00
0.57
2.21
2.63
0.46
0.57
0.00
1.94
2.08
2.48
2.55
0.02
0.00
0.01
0.04
0.00
0.02
0.00
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
0
1
2
3
4
5
6
7
8
9
10
Time
29.06.2012 10:30
29.06.2012 10:35
29.06.2012 11:00
29.06.2012 11:30
29.06.2012 12:30
29.06.2012 13:30
29.06.2012 14:30
29.06.2012 15:30
29.06.2012 17:00
30.06.2012 09:00
30.06.2012 14:00
Time since start [h]
0:00
0:05
0:30
1:00
2:00
3:00
4:00
5:00
6:30
22:30
27:30
0.3
Reactor
eff. Conc [mg/l]
Tim e vs Concentration, Mass
Trap 1
Sample Nr.
eff. Conc [mg/l]
Trap Volume 1 [ml]
Mass [mg]
0
0.00
82.00
1
0.14
78.72
2
0.04
78.72
3
0.03
77.08
4
0.09
74.62
5
0.18
72.98
6
0.27
70.52
7
0.37
68.06
8
0.57
66.42
9
2.08
64.78
10
2.55
62.32
0.00
0.01
0.00
0.00
0.01
0.01
0.02
0.03
0.04
0.13
0.16
Mass [mg]
0
2.13
1.77
1.48
0.00
0.64
0.53
0.44
0.98
0.30
0.97
0.29
Trap 2
eff. Conc [mg/l]
Trap Volume 1 [ml] Mass [mg]
0.00
82.00
0.03
78.75
0.00
78.75
0.00
77.13
0.00
75.50
0.00
73.07
0.00
71.45
0.00
69.01
0.00
67.39
0.01
65.76
0.02
63.33
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
31
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Tretrachloromethane
Results from the GC/MS analysis
Com ponent Nam e
Tetrachlormethan_117
Sam ple Nam e
0_2
0_6
1_0
1_5
1_L
1_GA
1_GB
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_ga_1
4_ga_2
4_gb
5_l
5_ga_1
5_ga_2
5_gb
6_ga_1
6_ga_2
6_gb
7_ga_1
7_ga_2
7_ga_4
7_gb
8_l
8_ga_2
8_ga_5
8_gb_1
8_gb_2
9_ga_2
9_ga_5
9_gb_2
9_gb_4
10_ga_2
10_ga_5
10_gb_2
10_gb_4
Area
1160912
2825049
4473456
6617468
2458812
935448
292294
1940525
397505
64551
1413252
394727
40653
1431870
738265
32672
1499657
3007824
1422613
34770
4227842
2103246
40565
5592028
2793967
1345938
43140
1020191
3999657
1451858
47376
31821
9174228
3379517
147014
86839
10342316
4051217
192142
103533
Equation
Y = 156517+4.33161e+006*X R^2 = 0.9982
Standards
Know Conc Calculated Conc
0.200
0.232
0.600
0.616
1.000
0.997
1.500
1.492
0.532
0.180
0.031
0.412
0.056
0.000
0.290
0.055
0.000
0.294
0.134
0.000
0.310
0.658
0.292
0.000
0.940
0.449
0.000
1.255
0.609
0.275
0.000
0.199
0.887
0.299
0.000
0.000
2.082
0.744
0.000
0.000
2.352
0.899
0.008
0.000
%Diff
16%
3%
0%
-1%
%RSD
0.0%
0.0%
0.0%
0.0%
Dilution
Dillusion - effective concentration [m g/l]
Dillusion
1
Reaktor
1
2
2.5
Average
Trap 1
1
2
4
5
Average
Trap 2
1
2
4
Average
assume
high
low
2
3
4
5
0.31
0.82
0.58
1.33
1.33
0.18
0.82
0.06
0.58
0.05
0.18
0.03
0.06
0.00
0.00
0.03
0.29
0.27
0.31
0.66
0.58
0.05
0.00
0.28
0.00
0.62
0.00
0.00
0.00
0.00
best range
32
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Dillusion
Reaktor
Trap 1
Trap 2
6
1
2
2.5
Average
1
2
4
5
Average
1
2
4
Average
7
8
9
10
0.20
0.20
0.94
0.90
1.25
1.22
1.10
0.92
0.00
1.24
0.00
0.00
0.00
1.77
4.16
4.70
1.50
1.77
0.00
3.72
3.94
4.50
4.50
0.00
0.00
0.00
0.02
0.00
0.01
0.00
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
0
1
2
3
4
5
6
7
8
9
10
Time
29.06.2012 10:30
29.06.2012 10:35
29.06.2012 11:00
29.06.2012 11:30
29.06.2012 12:30
29.06.2012 13:30
29.06.2012 14:30
29.06.2012 15:30
29.06.2012 17:00
30.06.2012 09:00
30.06.2012 14:00
Time since start [h]
0:00
0:05
0:30
1:00
2:00
3:00
4:00
5:00
6:30
22:30
27:30
0.3
Reactor
eff. Conc [mg/l]
Tim e vs Concentration, Mass
Trap 1
Sample Nr.
eff. Conc [mg/l]
Trap Volume 1 [ml]
Mass [mg]
0
0.00
82.00
1
0.18
78.72
2
0.06
78.72
3
0.05
77.08
4
0.28
74.62
5
0.62
72.98
6
0.92
70.52
7
1.24
68.06
8
1.77
66.42
9
3.94
64.78
10
4.50
62.32
0.00
0.01
0.00
0.00
0.02
0.05
0.06
0.08
0.12
0.26
0.28
Mass [mg]
0
1.33
0.82
0.58
0.00
0.40
0.25
0.17
0.31
0.09
0.20
0.06
Trap 2
eff. Conc [mg/l]
Trap Volume 1 [ml] Mass [mg]
0.00
82.00
0.03
78.75
0.00
78.75
0.00
77.13
0.00
75.50
0.00
73.07
0.00
71.45
0.00
69.01
0.00
67.39
0.00
65.76
0.01
63.33
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
33
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Chlorobenzene
Results from the GC/MS analysis
Com ponent Nam e
Chlorbenzol_112
Sam ple Nam e
0_2
0_6
1_0
1_5
1_L
1_GA
1_GB
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_ga_1
4_ga_2
4_gb
5_l
5_ga_1
5_ga_2
5_gb
6_ga_1
6_ga_2
6_gb
7_ga_1
7_ga_2
7_ga_4
7_gb
8_l
8_ga_2
8_ga_5
8_gb_1
8_gb_2
9_ga_2
9_ga_5
9_gb_2
9_gb_4
10_ga_2
10_ga_5
10_gb_2
10_gb_4
Area
1751629
4426801
7227253
10676229
7370276
1785261
1095594
8671052
716694
317936
6197833
410905
140202
442667
719071
85225
5528067
1043507
903844
76221
1592851
964086
88072
2257227
1531960
704664
56640
4464081
1736805
757071
94238
115318
5345778
2158444
114912
117084
6649372
2695892
72283
53916
Equation
Y = 173990+7.03393e+006*X R^2 = 0.9991
Standards
Know Conc Calculated Conc
0.200
0.224
0.600
0.605
1.000
1.003
1.500
1.493
1.023
0.229
0.131
1.208
0.077
0.020
0.856
0.034
0.000
0.038
0.077
0.000
0.761
0.124
0.104
0.000
0.202
0.112
0.000
0.296
0.193
0.075
0.000
0.610
0.222
0.083
0.000
0.000
0.735
0.282
0.000
0.000
0.921
0.359
0.000
0.000
%Diff
12%
1%
0%
0%
%RSD
0.0%
0.0%
0.0%
0.0%
Dilution
Dillusion - effective concentration [m g/l]
Dillusion
1
Reaktor
1
2
2.5
Average
Trap 1
1
2
4
5
Average
Trap 2
1
2
4
Average
assume
high
low
2
3
4
5
0.76
2.42
1.71
2.56
2.56
0.23
2.42
0.08
1.71
0.03
0.23
0.13
0.08
0.02
0.02
0.13
0.04
0.15
0.76
0.12
0.21
0.03
0.00
0.10
0.00
0.17
0.00
0.00
0.00
0.00
best range
34
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Dillusion
Reaktor
Trap 1
Trap 2
6
1
2
2.5
Average
1
2
4
5
Average
1
2
4
Average
7
8
9
10
0.61
0.61
0.20
0.22
0.30
0.39
0.30
0.21
0.00
0.34
0.00
0.00
0.00
0.44
1.47
1.84
0.41
0.44
0.00
1.41
1.44
1.79
1.82
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
0
1
2
3
4
5
6
7
8
9
10
Time
29.06.2012 10:30
29.06.2012 10:35
29.06.2012 11:00
29.06.2012 11:30
29.06.2012 12:30
29.06.2012 13:30
29.06.2012 14:30
29.06.2012 15:30
29.06.2012 17:00
30.06.2012 09:00
30.06.2012 14:00
Time since start [h]
0:00
0:05
0:30
1:00
2:00
3:00
4:00
5:00
6:30
22:30
27:30
0.3
Reactor
eff. Conc [mg/l]
Tim e vs Concentration, Mass
Trap 1
Sample Nr.
eff. Conc [mg/l]
Trap Volume 1 [ml]
Mass [mg]
0
0.00
82.00
1
0.23
78.72
2
0.08
78.72
3
0.03
77.08
4
0.10
74.62
5
0.17
72.98
6
0.21
70.52
7
0.34
68.06
8
0.44
66.42
9
1.44
64.78
10
1.82
62.32
0.00
0.02
0.01
0.00
0.01
0.01
0.02
0.02
0.03
0.09
0.11
Mass [mg]
0
2.56
2.42
1.71
0.00
0.77
0.72
0.51
0.76
0.23
0.61
0.18
Trap 2
eff. Conc [mg/l]
Trap Volume 1 [ml] Mass [mg]
0.00
82.00
0.13
78.75
0.02
78.75
0.00
77.13
0.00
75.50
0.00
73.07
0.00
71.45
0.00
69.01
0.00
67.39
0.00
65.76
0.00
63.33
0.00
0.01
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
35
Appendix: Formation of chlorinated organics during electrolytic urine treatment
5.4.2. Concentration changing with time: Graph
Figure 7: Experiment Air_2. Concentration of chlorinated organics at three different places in the system
changing with time. 1.2mg/l of chlorinated organics spiked into a reactor of 300ml distilled water. No current
applied, turbulence generated with a high turbulence magnetic stirrer. Evolving gas sucked through two traps of
82ml dodecane each (1.04l/h). Data points with orange box: concentration higher than calibration range.
In the reactor there were no data points available after 7 hours. The values in gray are
below the calibration range and are assumed to be zero. The values in orange are above
the calibration range and might be underestimated.
36
Appendix: Formation of chlorinated organics during electrolytic urine treatment
5.5.
Experiment Blank_4
5.5.1. Data
Dichloromethane
Results from the GC/MS analysis
Com ponent Nam e
Dichlormethan_84
Sam ple Nam e
0_2
0_6
1_0
1_5
0_l
0_ga
0_gb
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga_2
3_ga_4
3_gb
4_ga_2
4_ga_5
4_ga
5_l
5_ga
5_gb
6_ga
6_gb
7_l
7_ga
7_gb
8_l
8_ga_2
8_ga_5
8_gb
9_ga
9_gb
10_l
10_ga
10_gb
11_l
11_ga
11_gb
12_l
12_ga_1
12_ga_2
12_gb_2
12_gb_4
13_ga
13_ga
Area
817030
1330912
2665292
4385479
531612
1046748
802552
1407267
288593
114966
3018146
723417
61113
3796762
1161257
641574
45298
3574160
1492379
530730
185791
2761581
665624
2148514
1391297
648370
1889578
2621896
30683
1418059
562667
3131699
872632
1332943
39159
441829
908960
14642
125458
187185
134811
265595
157864
175823
133074
114623
96912
Equation
Y = -13957.7+2.80864e+006*X R^2 = 0.9797
Standards
Calc. Am ount (new )
Know Conc
0.290
0.200
0.472
0.600
0.945
1.000
1.556
1.500
0.189
0.371
0.285
0.499
0.102
0.041
1.071
0.257
0.022
1.347
0.412
0.228
0.016
1.268
0.529
0.188
0.066
0.980
0.236
0.762
0.493
0.230
0.670
0.930
0.011
0.503
0.200
1.111
0.310
0.473
0.014
0.157
0.322
0.005
0.044
0.066
0.048
0.094
0.056
0.062
0.047
0.041
0.034
Am ount
0.296
0.479
0.954
1.566
0.194
0.378
0.291
0.506
0.108
0.046
1.080
0.263
0.027
1.357
0.418
0.233
0.021
1.278
0.536
0.194
0.071
0.988
0.242
0.770
0.500
0.236
0.678
0.938
0.016
0.510
0.205
1.120
0.316
0.480
0.019
0.162
0.329
0.010
0.050
0.072
0.053
0.100
0.061
0.068
0.052
0.046
0.039
%Diff
48%
-20%
-5%
4%
-3%
-2%
-2%
-1%
-5%
-13%
-1%
-2%
-23%
-1%
-2%
-3%
-31%
-1%
-1%
-3%
-8%
-1%
-2%
-1%
-1%
-3%
-1%
-1%
-46%
-1%
-3%
-1%
-2%
-1%
-36%
-4%
-2%
-96%
-12%
-8%
-11%
-6%
-9%
-8%
-11%
-13%
-15%
%RSD
0.0%
0.0%
0.0%
0.0%
Yellow: calculated with new equation (%Diff = comparison with “Amount”)
37
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Dilution
assume
high
Dillusion
Reaktor
low
0
best range
1
1
2
2.5
Average
1
2
4
5
Average
1
2
4
Average
Trap 1
Trap 2
Dillusion
Trap 1
Trap 2
3
4
5
0.07
1.27
1.27
0.11
0.19
0.38
0.38
0.29
0.11
0.05
2.16
2.71
2.16
2.71
0.53
0.84
0.93
0.53
0.03
0.89
0.02
0.07
2.56
2.68
2.62
0.19
4.94
4.94
0.48
0.29
0 = Null Messung
Reaktor
2
0.19
6
1
2
2.5
Average
1
2
4
5
Average
1
2
4
Average
0.05
0.03
0.02
1 = 5min nach Spiki 2 = 15min nach Electrolysis einschalten
7
8
9
10
0.19
11
0.48
12
0.24
0.02
0.02
0.01
0.05
0.24
0.02
0.02
0.01
1.02
0.63
0.32
0.10
0.05
0.10
0.12
3.85
3.85
3.39
3.39
1.03
1.02
0.63
0.32
0.10
0.11
1.00
1.88
2.24
0.96
0.66
0.14
1.00
1.88
2.24
0.96
0.66
0.14
0.14
0.21
0.17
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
0
1
2
3
4
5
6
7
8
9
10
11
12
Time
Nullmessung
04.07.2012 11:30
04.07.2012 11:45
04.07.2012 12:15
04.07.2012 13:15
04.07.2012 14:15
04.07.2012 16:15
04.07.2012 18:00
05.07.2012 09:00
05.07.2012 13:30
05.07.2012 17:00
06.07.2012 09:00
06.07.2012 15:00
0.3
Reactor
Time since start [h] eff. Conc [mg/l]
Mass [mg]
0.19
0.06
0:00
1.27
0.38
0:15
2.16
0.65
0:45
2.71
0.81
1:45
2:45
0.07
0.02
4:45
6:30
0.24
0.07
21:30
0.02
0.00
26:00
29:30
0.02
0.01
45:30
0.01
0.00
51:30
0.05
0.02
Tim e vs Concentration, Mass
Trap 1
Trap Volume 1 [ml Mass [mg]
eff. Conc [mg/l]
0.38
82.00
0.11
82.00
0.53
80.36
0.89
75.44
2.62
74.62
4.94
72.16
3.85
69.70
3.39
68.88
1.02
67.20
0.63
65.03
0.32
64.23
0.10
62.62
0.11
61.01
0.03
0.01
0.04
0.07
0.20
0.36
0.27
0.23
0.07
0.04
0.02
0.01
0.01
Trap 2
eff. Conc [mg/l]
Trap Volume 2 [Mass [mg]
0.29
82.00
0.05
82.00
0.03
79.54
0.02
74.62
0.19
73.80
0.48
72.16
1.00
70.52
1.88
69.70
2.24
67.60
0.96
64.71
0.66
63.90
0.14
62.28
0.17
61.47
0.02
0.00
0.00
0.00
0.01
0.03
0.07
0.13
0.15
0.06
0.04
0.01
0.01
38
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Trichloromethane
Results from the GC/MS analysis
Com ponent Nam e
Chloroform_83
Sam ple Nam e
0_2
0_6
1_0
1_5
0_l
0_ga
0_gb
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga_2
3_ga_4
3_gb
4_ga_2
4_ga_5
4_ga
5_l
5_ga
5_gb
6_ga
6_gb
7_l
7_ga
7_gb
8_l
8_ga_2
8_ga_5
8_gb
9_ga
9_gb
10_l
10_ga
10_gb
11_l
11_ga
11_gb
12_l
12_ga_1
12_ga_2
12_gb_2
12_gb_4
13_ga
13_ga
Area
2015672
2487851
4843175
7656806
1833078
3062760
2455307
2873883
454125
185498
3734995
1447948
74142
3359114
2396007
1603886
48315
5296494
2570418
384296
1002517
4690498
641588
4377204
1266219
431047
3974793
2064077
166997
5627004
2274576
5680876
4934409
4662237
170837
3841587
4414342
129339
1807103
2807339
2611072
3705375
2128825
3183059
1911890
1901880
1859107
Equation
Y = 261255+4.75674e+006*X R^2 = 0.9651
Standards
Know Conc
Calculated Conc
0.200
0.369
0.600
0.468
1.000
0.963
1.500
1.555
0.330
0.589
0.461
0.549
0.041
0.000
0.730
0.249
0.000
0.651
0.449
0.282
0.000
1.059
0.485
0.026
0.156
0.931
0.080
0.865
0.211
0.036
0.781
0.379
0.000
1.128
0.423
1.139
0.982
0.925
0.000
0.753
0.873
0.000
0.325
0.535
0.000
0.724
0.393
0.614
0.347
0.345
0.336
%Diff
84%
-22%
-4%
4%
%RSD
0.0%
0.0%
0.0%
0.0%
39
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Dilution
assume
high
Dillusion
Reaktor
Trap 1
Trap 2
1
2
2.5
Average
1
2
4
5
Average
1
2
4
Average
Dillusion
Reaktor
Trap 1
Trap 2
low
0
best range
1
2
3
4
5
0.33
1.37
1.37
0.04
0.33
0.59
0.59
0.46
0.04
0.00
0.46
6
1
2
2.5
Average
1
2
4
5
Average
1
2
4
Average
6
0.16
0.00
7
1.46
1.30
1.46
1.30
0.50
0.90
1.13
0.50
0.00
1.01
0.00
0.00
8
0.16
2.12
2.43
2.27
0.03
0.00
9
0.03
10
4.66
4.66
4.33
4.33
0.16
0.42
0.16
0.42
11
12
0.04
0.00
0.00
0.00
0.00
0.04
0.00
0.00
0.00
2.26
1.96
1.51
0.65
0.00
0.72
0.79
4.33
4.33
3.90
3.90
2.12
2.19
1.96
1.51
0.65
0.75
0.42
0.76
2.28
1.85
1.75
1.07
0.42
0.76
2.28
1.85
1.75
1.07
1.23
1.39
1.31
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
0
1
2
3
4
5
6
7
8
9
10
11
12
Time
Nullmessung
04.07.2012 11:30
04.07.2012 11:45
04.07.2012 12:15
04.07.2012 13:15
04.07.2012 14:15
04.07.2012 16:15
04.07.2012 18:00
05.07.2012 09:00
05.07.2012 13:30
05.07.2012 17:00
06.07.2012 09:00
06.07.2012 15:00
0.3
Reactor
me since start [h] eff. Conc [mg/l] Mass [mg]
0.33
0.10
0:00
1.37
0.41
0:15
1.46
0.44
0:45
1.30
0.39
1:45
0.00
2:45
0.16
0.05
4:45
0.00
6:30
0.04
0.01
21:30
0.00
0.00
26:00
0.00
29:30
0.00
0.00
45:30
0.00
0.00
51:30
0.00
0.00
Tim e vs Concentration, Mass
Trap 1
Trap 2
eff. Conc [mg/l] Trap Volume 2 [mMass [mg]
Trap Volume 1 [mMass [mg]
Sample Nr.
eff. Conc [mg/l]
0
0.59
82.00
0.05
0.46
82.00
0.04
1
0.04
82.00
0.00
0.00
82.00
0.00
2
0.50
80.36
0.04
0.00
79.54
0.00
3
1.01
75.44
0.08
0.00
74.62
0.00
4
2.27
74.62
0.17
0.03
73.80
0.00
5
4.66
72.16
0.34
0.16
72.16
0.01
6
4.33
69.70
0.30
0.42
70.52
0.03
7
3.90
68.88
0.27
0.76
69.70
0.05
8
2.19
67.20
0.15
2.28
67.60
0.15
9
1.96
65.03
0.13
1.85
64.71
0.12
10
1.51
64.23
0.10
1.75
63.90
0.11
11
0.65
62.62
0.04
1.07
62.28
0.07
12
0.75
61.01
0.05
1.31
61.47
0.08
40
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Tretrachloromethane
Results from the GC/MS analysis
Com ponent Nam e
Tetrachlormethan_117
Sam ple Nam e
0_2
0_6
1_0
1_5
0_l
0_ga
0_gb
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga_2
3_ga_4
3_gb
4_ga_2
4_ga_5
4_ga
5_l
5_ga
5_gb
6_ga
6_gb
7_l
7_ga
7_gb
8_l
8_ga_2
8_ga_5
8_gb
9_ga
9_gb
10_l
10_ga
10_gb
11_l
11_ga
11_gb
12_l
12_ga_1
12_ga_2
12_gb_2
12_gb_4
13_ga
13_ga
Area
891005
1212210
2527219
4282392
2048651
3349768
2544499
1591594
323338
50221
1272876
1448039
37573
793049
2842295
2001837
22323
5266969
2521362
236760
288552
3978553
295911
4276320
632012
134763
4094526
1028023
31151
8738316
3402227
3923296
8529744
4099446
31502
7689866
4442848
14674
5728724
4812618
812315
10517263
5250075
5538936
2909396
2956889
2907732
Equation
Y = 803.222+2.69964e+006*X R^2 = 0.9664
Standards
Know Conc
Calculated Conc
0.200
0.330
0.600
0.449
1.000
0.936
1.500
1.586
0.759
1.241
0.942
0.589
0.119
0.018
0.471
0.536
0.014
0.293
1.053
0.741
0.008
1.951
0.934
0.087
0.107
1.473
0.109
1.584
0.234
0.050
1.516
0.381
0.011
3.237
1.260
1.453
3.159
1.518
0.011
2.848
1.645
0.005
2.122
1.782
0.301
3.896
1.944
2.051
1.077
1.095
1.077
%Diff
65%
-25%
-6%
6%
%RSD
0.0%
0.0%
0.0%
0.0%
41
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Dilution
assume
high
Dillusion
Reaktor
low
0
1
2
2.5
Average
1
2
4
5
Average
1
2
4
Average
Trap 1
Trap 2
Dillusion
Reaktor
Trap 1
Trap 2
best range
1
2
3
4
5
0.76
1.47
1.47
0.12
0.76
1.24
1.24
0.94
0.12
0.02
0.94
0.59
0.94
0.59
1.07
2.11
2.96
1.07
0.01
2.53
0.01
0.11
3.90
4.67
4.28
0.09
0.94
0.02
0.01
0.01
0 = Null Messung 1 = 5min nach Spi 2 = 15min nach Electrolysis einschalten
6
1
2
2.5
Average
1
2
4
5
Average
1
2
4
Average
6
0.11
7
8
9
0.09
10
7.37
7.37
7.92
7.92
0.22
0.47
0.22
0.47
11
12
0.05
0.01
0.01
0.01
0.30
0.05
0.01
0.01
0.01
6.47
6.32
5.70
4.24
0.30
3.90
3.89
7.92
7.92
7.58
7.58
6.30
6.30
6.32
5.70
4.24
3.89
0.47
0.76
2.91
3.04
3.29
3.56
0.47
0.76
2.91
3.04
3.29
3.56
4.10
4.31
4.21
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
0
1
2
3
4
5
6
7
8
9
10
11
12
Time
Nullmessung
04.07.2012 11:30
04.07.2012 11:45
04.07.2012 12:15
04.07.2012 13:15
04.07.2012 14:15
04.07.2012 16:15
04.07.2012 18:00
05.07.2012 09:00
05.07.2012 13:30
05.07.2012 17:00
06.07.2012 09:00
06.07.2012 15:00
0.3
Reactor
ime since start [h] eff. Conc [mg/l]
0.76
0:00
1.47
0:15
0.94
0:45
0.59
1:45
2:45
0.11
4:45
6:30
0.05
21:30
0.01
26:00
29:30
0.01
45:30
0.01
51:30
0.30
Tim e vs Concentration, Mass
Trap 1
Trap Volume 1 [mlMass [mg]
Sample Nr.
eff. Conc [mg/l]
0
1.24
82.00
1
0.12
82.00
2
1.07
80.36
3
2.53
75.44
4
4.28
74.62
5
7.37
72.16
6
7.92
69.70
7
7.58
68.88
8
6.30
67.20
9
6.32
65.03
10
5.70
64.23
11
4.24
62.62
12
3.89
61.01
0.10
0.01
0.09
0.19
0.32
0.53
0.55
0.52
0.42
0.41
0.37
0.27
0.24
Trap 2
eff. Conc [mg/l] Trap Volume 2 [m Mass [mg]
0.94
82.00
0.02
82.00
0.01
79.54
0.01
74.62
0.09
73.80
0.22
72.16
0.47
70.52
0.76
69.70
2.91
67.60
3.04
64.71
3.29
63.90
3.56
62.28
4.21
61.47
0.08
0.00
0.00
0.00
0.01
0.02
0.03
0.05
0.20
0.20
0.21
0.22
0.26
42
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Chlorobenzene
Results from the GC/MS analysis
Com ponent Nam e
Chlorbenzol_112
Sam ple Nam e
0_2
0_6
1_0
1_5
0_l
0_ga
0_gb
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga_2
3_ga_4
3_gb
4_ga_2
4_ga_5
4_gb
5_l
5_ga
5_gb
6_ga
6_gb
7_l
7_ga
7_gb
8_l
8_ga_2
8_ga_5
8_gb
9_ga
9_gb
10_l
10_ga
10_gb
11_l
11_ga
11_gb
12_l
12_ga_1
12_ga_2
12_gb_2
12_gb_4
13_ga
13_ga
Area
1001288
1590576
3433355
5955517
555097
1150680
2171644
2298243
171584
51987
2735448
366330
63716
2524619
139158
174205
23351
303632
346421
59176
2772149
502114
139567
2203067
106618
2171592
2996972
49211
563004
25352470
9559152
837289
30412111
1343141
431305
32293467
1782718
231601
39816377
3689271
923987
85318541
44745062
5450024
2954461
2998509
3098926
Equation
Y = -120976+3.81382e+006*X R^2 = 0.9696
Standards
Know Conc
Calculated Conc
0.200
0.294
0.600
0.449
1.000
0.932
1.500
1.593
0.177
0.000
0.000
0.634
0.077
0.045
0.749
0.128
0.048
0.694
0.068
0.077
0.038
0.111
0.123
0.047
0.759
0.163
0.068
0.609
0.060
0.601
0.818
0.045
0.179
6.679
2.538
0.251
8.006
0.384
0.145
8.499
0.499
0.092
10.472
0.999
0.274
22.403
11.764
1.461
0.806
0.818
0.844
%Diff
47%
-25%
-7%
6%
%RSD
0.0%
0.0%
0.0%
0.0%
43
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Dilution
assume
0
Dillusion
Reaktor
Trap 1
Trap 2
1
2
2.5
Average
1
2
4
5
Average
1
2
4
Average
Dillusion
Reaktor
Trap 1
Trap 2
1
2
2.5
Average
1
2
4
5
Average
1
2
4
Average
high
1
low
2
best range
3
4
5
0.18
0.76
1.59
1.59
0.08
0.18
0.00
0.00
0.00
0.08
0.05
1.50
1.39
1.50
1.39
0.26
0.14
0.31
0.26
0.05
0.22
0.04
0.76
0.22
0.61
0.42
0.05
0.82
0.82
0.14
0.00
0.05
0.05
0.04
0 = Null Messung
1 = 5min nach Spiking 2 = 15min nach Electrolysis einschalten
6
7
8
9
10
0.05
11
0.14
12
0.60
0.18
0.14
0.09
0.27
0.60
0.18
0.14
0.09
13.36
16.01
17.00
20.94
0.27
22.40
23.53
3.05
3.05
4.09
4.09
12.69
13.02
16.01
17.00
20.94
22.97
0.12
0.09
0.50
0.77
1.00
2.00
0.12
0.09
0.50
0.77
1.00
2.00
2.92
3.23
3.07
Calculated concentrations and masses.
Sample Nr.
0
1
2
3
4
5
6
7
8
9
10
11
12
Reactor
me since start [h] eff. Conc [mg/l] Mass [mg]
Time
Nullmessung
0.18
0.05
04.07.2012 11:30
0:00
1.59
0.48
04.07.2012 11:45
0:15
1.50
0.45
04.07.2012 12:15
0:45
1.39
0.42
04.07.2012 13:15
1:45
04.07.2012 14:15
2:45
0.76
0.23
04.07.2012 16:15
4:45
04.07.2012 18:00
6:30
0.60
0.18
05.07.2012 09:00
21:30
0.18
0.05
05.07.2012 13:30
26:00
05.07.2012 17:00
29:30
0.14
0.04
06.07.2012 09:00
45:30
0.09
0.03
06.07.2012 15:00
51:30
0.27
0.08
Tim e vs Concentration, Mass
Trap 1
Trap 2
Trap Volume 1 [mMass [mg]
eff. Conc [mg/l] Trap Volume 2 [mMass [mg]
Sample Nr.
eff. Conc [mg/l]
0
0.00
82.00
0.00
0.00
82.00
0.00
1
0.08
82.00
0.01
0.05
82.00
0.00
2
0.26
80.36
0.02
0.05
79.54
0.00
3
0.22
75.44
0.02
0.04
74.62
0.00
4
0.42
74.62
0.03
0.05
73.80
0.00
5
0.82
72.16
0.06
0.14
72.16
0.01
6
3.05
69.70
0.21
0.12
70.52
0.01
7
4.09
68.88
0.28
0.09
69.70
0.01
8
13.02
67.20
0.88
0.50
67.60
0.03
9
16.01
65.03
1.04
0.77
64.71
0.05
10
17.00
64.23
1.09
1.00
63.90
0.06
11
20.94
62.62
1.31
2.00
62.28
0.12
12
22.97
61.01
1.40
3.07
61.47
0.19
44
Appendix: Formation of chlorinated organics during electrolytic urine treatment
5.5.2. Mass balance: Reactor vs. tap 1 and trap 2
For the time frame indicated with pink in figure 9 in the report, it is assumed that the
solution is perfectly mixed and nothing enters the reactor anymore. So if there is no loss out
of the system, everything that leaves the reactor can be found in either trap 1 or trap 2.
Dichloromethane:
① Mass balance: reactor vs. trap 1 and trap 2
Time
Reactor [mg]
0:45
2:45
Trap 1 [mg]
Trap 2 [mg]
0.81
0.02
0.793
Difference
0.07
0.36
0.29
Recovery:
0.00
0.03
0.03
41%
Trichloromethane:
① Mass balance: reactor vs. trap 1 and trap 2
Time
Reactor [mg]
0:15
2:45
Trap 1 [mg]
0.44
0.05
0.391
Trap 2 [mg]
0.04
0.34
0.30
Recovery:
0.00
0.01
0.01
79%
Tetrachloromethane:
① Mass balance: reactor vs. trap 1 and trap 2
Time
Reactor [mg]
0:05
2:45
Trap 1 [mg]
0.44
0.03
0.410
Trap 2 [mg]
0.01
0.53
0.52
Recovery:
0.00
0.02
0.01
131%
Chlorobenzene:
① Mass balance: reactor vs. trap 1 and trap 2
Time
Reactor [mg]
0:05
6:30
Trap 1 [mg]
0.48
0.18
0.295
Trap 2 [mg]
0.01
0.28
0.28
Recovery:
0.00
0.01
0.00
94%
45
Appendix: Formation of chlorinated organics during electrolytic urine treatment
5.5.3. Mass balance: trap 1 vs. Trap 2
For the time frame indicated in the figure 8 below, it is assumed, that nothing from the
reactor enters trap 1 anymore. For chlorobenzene this situation never occurs during the
experiment. For the other substances it is assumed, that if there is no loss out of the
system, everything that leaves trap 1 should be found in trap 2.
Figure 8: Mass balance: Mass found in trap 1 and trap 2 respectively, divided by the mass maximally
2
found in the reactor. Reactor of 300ml 1M NaClO4 solution. Applied current density: 5mA/m . Evolving gas
sucked through two traps of 82ml dodecane each. Pink square: Nothing enters trap 1 anymore  Ideal:
Everything that leaves trap 1 enters trap 2. .
Dichloromethane:
② Mass balance: trap 1 vs. trap 2
Time
Trap 1
Trap 2
4:45
21:30
0.27
0.07
0.200
Difference
Recovery:
0.07
0.15
0.08
41%
Trichloromethane:
② Mass balance: trap 1 vs. trap 2
Time
Trap 1
Trap 2
4:45
21:30
0.30
0.15
0.155
Recovery:
0.03
0.15
0.12
80%
Tetrachloromethane:
② Mass balance: trap 1 vs. trap 2
Time
Trap 1
4:45
51:30
Trap 2
0.55
0.24
0.314
Recovery:
0.03
0.26
0.23
72%
46
Appendix: Formation of chlorinated organics during electrolytic urine treatment
6. Correlation: Trap vs. gas leaving the trap
Figure 9: Correlation between the concentration in trap 1 and the concentration in the gas leaving trap 1
and. Concentration in the gas leaving trap 1 calculated with the concentration in trap 2.
47
Appendix: Formation of chlorinated organics during electrolytic urine treatment
7. Model
7.1.
Concept
It was assumed, that the gas bubbles are in equilibrium with the liquid phase, when leaving
the reactor or the traps:
Concentration in reactor liquid: Cr
𝑑
1
𝐶𝑟 =
∗ (𝑀𝑖𝑛 − 𝑄𝑔 ∗ 𝐻 ∗ 𝐶𝑟 )
𝑑𝑡
𝑉𝑟
Concentration in gas over reactor liquid: Gg1
Concentration in trap 1: Ct1
𝐶𝑔1 = 𝐻 ∗ 𝐶𝑟
1
𝑑
𝐶𝑡1 =
∗ (𝑄𝐺 ∗ �𝐶𝑔1 − 𝐿 ∗ 𝐶𝑡1 � − 𝑄𝐺 ∗ 𝐿 ∗ 𝐶𝑡1 )
𝑉𝑡1
𝑑𝑡
Concentration in gas between traps: Cg2
𝐶𝑔2 = 𝐿 ∗ 𝐶𝑡1
Concentration in gas between traps: Ct2
1
𝑑
𝐶𝑡2 =
∗ (𝑄𝐺 ∗ �𝐶𝑔2 − 𝐿 ∗ 𝐶𝑡2 � − 𝑄𝐺 ∗ 𝐿 ∗ 𝐶𝑡2 )
𝑉𝑡2
𝑑𝑡
48
Appendix: Formation of chlorinated organics during electrolytic urine treatment
7.2.
Berkeley Madonna Code
“
METHOD RK4
STARTTIME = -1
STOPTIME=52
DT = 0.002
DTOUT = 1
;[h]
;[h]
{Parameters, 1M salinity }
V=
V_h =
Q_g =
V_t=
Q_q =
M_t =
0.3
0.137
0.069
0.082
1.74
1.2
;Reactor volume [l]
;Headspace volume of reactor [l]
;Gas flow [l/h]
;trap volume [l]
;Gas flow by sucking pump (ca 29 ml/min) [l/h]
;targeted mass spiked to reactor [mg]
H_1 =
H_2 =
H_3 =
H_4 =
0.14
0.21
1.36
0.24
;Henry coeff. Dichloromethane [l,g/l,H2O]
;Henry coeff. Trichloromethane [l,g/l,H2O]
;Henry coeff. Trichloromethane [l,g/l,H2O]
;Henry coeff. Trichloromethane [l,g/l,H2O]
H[1] =
H[2] =
H[3] =
H[4] =
H_1
H_2
H_3
H_4
;Henry coeff. Dichloromethane [l,g/l,H2O]
;Henry coeff. Trichloromethane [l,g/l,H2O]
;Henry coeff. Tetrachloromethane [l,g/l,H2O]
;Henry coeff. Chlorobenzene [l,g/l,H2O]
L_1 =
L_2 =
L_3 =
L_4 =
0.0096
0.0033
0.0015
0.0002
;Henry coeff. Dichloromethane [l,g/l,H2O]
;Henry coeff. Trichloromethane [l,g/l,H2O]
;Henry coeff. Trichloromethane [l,g/l,H2O]
;Henry coeff. Trichloromethane [l,g/l,H2O]
L[1] =
L[2] =
L[3] =
L[4] =
L_1
L_2
L_3
L_4
;Partition coeff. Dichloronethane [l,g/l,H2O]
;Partition coeff. Trichloromethane [l,g/l,H2O]
;Partition coeff. Tetrachloromethane [l,g/l,H2O]
;Partition coeff. Chlorobenzene [l,g/l,H2O]
{Pulse, Blank 1}
M_in = Pulse(M_t, 0, 1000)
;(mass spiked into the reactor [mg], time spiked in [h], repeat at)
{Const. input}
;C_in = 1
;assume 1mg/h chlorinated organics produced
{Initial conditions}
init C_r[1..4] = 0
init C_t1[1..4] = 0
init C_t2[1..4] = 0
init C_g1[1..4] = 0
;initial condition for reactor conc. [mg/l]
;initial concentration in first trap [mg/l]
;initial concentration in second trap [mg/l]
;initial condition for headspace of reactor conc. [mg/l]
{For Fitting}
Cr_1 = C_r[1]
Cr_2 = C_r[2]
Cr_3 = C_r[3]
Cr_4 = C_r[4]
49
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Ct1_1 = C_t1[1]
Ct1_2 = C_t1[2]
Ct1_3 = C_t1[3]
Ct1_4 = C_t1[4]
Ct2_1 = C_t2[1]
Ct2_2 = C_t2[2]
Ct2_3 = C_t2[3]
Ct2_4 = C_t2[4]
{Diff. equation}
d/dt(C_r[1..4]) = 1/V * (M_in - Q_g * H[i] * C_r[i])
; conc. in Reactor
;d/dt(C_r[1..4]) = 1/V * (C_in - Q_g * H[i] * C_r[i])
input
; conc. in Reactor
const.
d/dt(C_g1[1..4]) =1/V_h * (Q_g * H[i] * C_r[i] - Q_q * C_g1[i])
;conc. in headspace of reactor
d/dt(C_t1[1..4]) = 1/V_T* Q_q * (C_g1[i] - L[i]*C_t1[i])
;conc. in first trap
C_g2[1..4] = L[i] * C_t1[i]
;conc. in gas phase between traps
d/dt(C_t2[1..4]) = 1/V_T* Q_q * (C_g2[i] - L[i]*C_t2[i])
;conc. in second trap
C_g3[1..4] = L[i] * C_t2[i]
{Calculations}
init MF_l[1..4] = 0
init MF_rout[1..4] = 0
init MF_t1out[1..4] = 0
init MF_t2out[1..4] = 0
;cumulative mass flux at liquid phase exit [mg]
;cumulative mass flux at exit of reactor [mg]
;cumulative mass flux at exit of trap1 [mg]
;cumulative mass flux at exit of trap2 [mg]
d/dt(MF_l[1..4]) = Q_g * H[i] * C_r[i]
d/dt(MF_rout[1..4]) = Q_q * C_g1[i]
d/dt(MF_t1out[1..4]) = Q_q * C_g2[i]
;integration of mass flux at liquid phase exit [mg]
;integration of mass flux at exit of reactor [mg]
;integration of mass flux at exit of trap1 [mg]
MF_t2out_1 = MF_t2out[1]
MF_t2out_2 = MF_t2out[2]
MF_t2out_3 = MF_t2out[3]
MF_t2out_4 = MF_t2out[4]
d/dt(MF_t2out[1..4]) = Q_q * L[i] * C_t2[i]
“
;integration of mass flux at exit of trap2 [mg]
50
Appendix: Formation of chlorinated organics during electrolytic urine treatment
7.3.
Fitted model
Figure 10: Experiment Blank_4. Concentration of chlorinated organics at three different places in the
system changing with time. Above: Model, below: Measured data.
In figure 10 it can be seen that the model displays the behavior of the substances
conceptually. But the fit is not very accurate. The substances move out of the reactor slower
than in reality and the movement into the traps is too slow for di- and trichloromethane. Also
the maximum concentrations do not correlate.
51
Appendix: Formation of chlorinated organics during electrolytic urine treatment
7.4.
Chlorobenzene concentration over time
Figure 11: Model of the chlorobenzene concentration increasing in three places of the system with a
constant building rate of chlorinated organics of 1mg/h.
To model a constant building rate following changes where done in the Berkeley Madonna
code:
“
M_in = 1
;assume 1mg/h chlorinated organics produced
d/dt(C_r[1..4]) = 1/V * (M_in - Q_g * H[i] * C_r[i])
; conc. in Reactor const. input
“
It can be seen that in the first 7 hours the building rate is higher in the reactor than in the
traps.
8. Additional voltammetry experiments
8.1.
Iridium dioxide electrode
Amstutz et al. (2012) found that in stored urine electrolyzed on a iridium dioxide electrode,
CO23- is present and competes with the process of ammonium oxidation, either by oxidation
of carbonate to percarbonate, or by chlorate formation triggered by the buffering effect of
the carbonate.
52
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Figure 12: Cyclic voltammetry experiment with a iridium dioxide electrode, a platinum wire as a counter
electrode and a MSE reference electrode. Scan rate: 200mV/s, scan from -1.3 V to 0.9 V vs. MSE, for all four
st
experiments the 1 cycle of five cycles are shown. Red lines: Lower and upper potential, chosen for urine
experiment with and without formation of chlorinated organics.
In figure 12 the results of the cyclic voltammetry experiment with a iridium dioxide electrode
can be seen. In the blank electrolyte two redox couples (oxidation peak with correlating
reduction peak) can be seen at around -0.9 V vs. MSE and 0.4 V vs. MSE. Kapalka et al
(2011) identified them as Ir(IV)/Ir(III) and Ir(V)/Ir(IV) respectively. When ammonia is added,
in the potential another oxidation and reduction peak appear in region between the two
redox couples of the blank electrolyte. These indicates that the ammonia influences the
redox reactions of the iridium dioxide surface. In the here presented results the effect is
much stronger than in the experiments of Kapalka et al. (2011).
Besides this redox couple an additional anodic peak appears at around 0.3 V vs. MSE and
has its maximum at around 0.52 V vs. MSE. This indicated the ammonia oxidation, which
appears in the same potential region as in the results of Kapalka et al(2011). With chloride
in the solution the current density at 0.9 V vs. MSE is 6 times higher than in a blank
electrolyte. It indicates the chloride oxidation. A cathodic peak can be seen at 0.7 V vs.
MSE, it indicates the reduction of the chlorine produced in the oxidation of chloride before.
The reason for the decrease in peak between the scan with only ammonia and the one with
both ammonia and chloride could be a difference in pH. For only ammonia it was 8.9 and for
ammonia and chloride it was 8.8. The ammonia oxidation is known to be very pH dependent
(Kapalka, 2011).
The two potentials for the urine experiment are thus:
•
•
Lower potential: 0.52 V vs. MSE ( = 1.16 V vs. NHE)
Upper potential: 0.85 V vs. MSE ( = 1.54 V vs. NHE)
53
Appendix: Formation of chlorinated organics during electrolytic urine treatment
8.2.
Changes in ammonia oxidation peaks with increasing cycle
number with three different electrodes
Figure 13: Cyclic voltammetry experiment with an iridium dioxide (-1’300mV to 900mV vs. MSE), a
graphite (-1’300mV to 1’300mV vs. MSE) and a boron doped diamond electrode (-2’300mV to 2’350mV vs
MSE). 5 Cycles. Scan rate: 200mV/s
All experiments were conducted with 5 cycles. It was expected that after 5 cycles, the
electrode is in an equilibrium state. For the maximum upper return potential of each
electrode the results of the voltammetry experiment is shown in figure 13. It can be seen
that the ammonia peak was decreasing from the first to the fifth cycle for the graphite and
the boron doped diamond electrode, but almost didn’t decrease for the iridium electrode.
An explanation could be that in the experiments with the iridium dioxide electrode the low
“switching potential” was deeper in the potential region of the hydrogen evolution reaction,
than in the experiments with the graphite and the boron doped diamond electrode. Due to
the above presented results an additional hypothesis is stated:
The ammonia oxidation on graphite, boron doped diamond and iridium dioxide electrodes is
inhibited by a low pH. This can be prevented when repeatedly a potential low enough is
applied, so that the protons get reduced to hydrogen gas.
This hypothesis contradicts Kapalka et al. (2011), which state that the inhibition of the
ammonia oxidation on a iridium dioxide electrode is due to nitrogen species adsorbed to the
electrode. To prove the here stated hypothesis additional experiments were conducted:
First the cyclic voltammetry experiment for the graphite electrode was repeated with an
upper potential of 1’350mV vs. MSE and a decreasing lower potential. At a potential of –
2’700mV vs. MSE the ammonia peak of the first and the fifth scan were almost the same.
With this experiment it is indicated, that also on graphite the ammonia oxidation is inhibited
and that this inhibition can be avoided when a low enough potential is applied. To prove that
the inhibition effect is not due to adsorbed nitrogen species linear sweep experiments from
0 to 1’350 mV vs. MSE were conducted (with a graphite electrode). In between the first five
runs the electrolyte was mixed to balance the local low pH at the electrode and in the
second five runs the electrolyte was not mixed. In the results it can be seen that the
ammonia oxidation peak is not decreasing in the first five runs, but decreases substantially
in the second fife runs. This is a strong indication that the inhibition is caused by low pH and
not by adsorbed nitrogen species, which can’t be desorbed by mixing the electrolyte.
54
Appendix: Formation of chlorinated organics during electrolytic urine treatment
9. Urine experiments
N/A = peak not available = not found
Orange: sample above the concentration range
Gray: sample below the concentration range
Green: liquid samples
9.1.
Blue: best range
Purple: assumed value
Average: Chosen value
Data - Experiment Eup_G1
The samples in Eup_G1 were not dilluted.
Dichloromethane
Results from the GC/MS analysis
Com ponent Nam e
Dichlormethan_84
Sam ple Nam e
0_2
0_6
1_0
1_5
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
Area
629884
1692261
2905947
3777467
54282
138272
185271
164653
402263
405099
436656
2724498
1102518
Equation
Y = 110843+2.56101e+006*X R^2 = 0.9898
Standards
Know Conc Calculated Conc
0.200
0.203
0.600
0.617
1.000
1.091
1.500
1.432
0.000
0.011
0.029
0.021
0.114
0.115
0.127
1.021
0.387
%Diff
1%
3%
9%
-5%
%RSD
0.0%
0.0%
0.0%
0.0%
Calculated concentrations and masses.
assume
high
Tim e vs Concentration, Mass
Sample Nr.
1
2
3
Time
10.07.2012 10:45
10.07.2012 12:45
10.07.2012 14:45
low
best range
0.3
Reactor
Time since start [h] eff. Conc [mg/l]
Mass [mg]
0:00
0.00
2:00
0.02
4:00
0.13
Tim e vs Concentration, Mass
Trap 1
Sample Nr.
eff. Conc [mg/l]
Trap Volume 1 [ml]
Mass [mg]
1
0.01
20.00
2
0.11
18.00
3
1.02
17.00
0.00
0.01
0.04
Trap 2
eff. Conc [mg/l]
Trap Volume 1 [ml]
Mass [mg]
0.00
0.03
20.00
0.00
0.11
18.00
0.02
0.39
16.00
0.00
0.00
0.01
Current efficiencies
Current efficiency [μg/C]
[C]
Reactor
Gas
3645.63
1.73E-03
3057.45
1.04E-02
6703.08
5.69E-03
C_trap 2
1.30E-03
8.02E-03
4.42E-03
C_g,out
0.07
0.25
0.18
0.0003
0.0009
0.0006
55
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Trichloromethane
Results from the GC/MS analysis
Com ponent Nam e
Chloroform_83
Sam ple Nam e
0_2
0_6
1_0
1_5
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
Equation
Y = 312510+5.56092e+006*X R^2 = 0.9954
Standards
Area
Know Conc Calculated Conc
1655171
0.200
3762559
0.600
6007419
1.000
8488431
1.500
138137
33785
29729
2719139
7127108
1290785
3959559
32097840
7637298
%Diff
0.241
0.620
1.024
1.470
0.000
0.000
0.000
0.433
1.225
0.176
0.656
5.716
1.317
%RSD
21%
3%
2%
-2%
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
1
2
3
Time
10.07.2012 10:45
10.07.2012 12:45
10.07.2012 14:45
0.3
Reactor
Time since start [h] eff. Conc [mg/l]
Mass [mg]
0:00
0.00
2:00
0.43
4:00
0.66
Tim e vs Concentration, Mass
Trap 1
Sample Nr.
eff. Conc [mg/l]
Trap Volume 1 [ml]
Mass [mg]
1
0.00
20.00
2
1.23
18.00
3
5.72
17.00
0.00
0.13
0.20
Trap 2
eff. Conc [mg/l]
Trap Volume 1 [ml] Mass [mg]
0.00
0.00
20.00
0.02
0.18
18.00
0.10
1.32
16.00
0.00
0.00
0.02
Current efficiencies
Current efficiency [μg/C]
[C]
Reactor
Gas
3645.63
3.56E-02
3057.45
2.19E-02
6703.08
2.94E-02
C_trap 2
7.82E-03
3.45E-02
2.00E-02
C_g,out
0.09
0.75
0.50
0.0001
0.0011
0.0007
56
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Tretrachloromethane
Results from the GC/MS analysis
Com ponent Nam e
Tetrachlormethan_117
Sam ple Nam e
0_2
0_6
1_0
1_5
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
Area
1319843
3337396
5440985
7769207
55036
112799
998561
78130
103711
2646175
412319
Equation
Y = 179912+5.14178e+006*X R^2 = 0.9980
Standards
Know Conc Calculated Conc
0.200
0.222
0.600
0.614
1.000
1.023
1.500
1.476
0.000
N/A
0.000
N/A
0.000
0.000
0.159
0.000
0.000
0.480
0.045
%Diff
11%
2%
2%
-2%
%RSD
0.0%
0.0%
0.0%
0.0%
N/A
N/A
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
1
2
3
Time
10.07.2012 10:45
10.07.2012 12:45
10.07.2012 14:45
0.3
Reactor
Time since start [h] eff. Conc [mg/l]
Mass [mg]
0:00
0.00
2:00
0.00
4:00
0.00
Tim e vs Concentration, Mass
Trap 1
Sample Nr.
eff. Conc [mg/l]
Trap Volume 1 [ml]
Mass [mg]
1
0.00
20.00
2
0.16
18.00
3
0.48
17.00
0.00
0.00
0.00
Trap 2
eff. Conc [mg/l]
Trap Volume 1 [ml] Mass [mg]
0.00
0.00
20.00
0.00
0.00
18.00
0.01
0.05
16.00
0.00
0.00
0.00
Current efficiencies
Current efficiency [μg/C]
[C]
Reactor
Gas
3645.63
0.00E+00
3057.45
0.00E+00
6703.08
0.00E+00
C_trap 2
8.73E-04
2.19E-03
1.46E-03
C_g,out
0.00
0.02
0.02
0.0000
0.0000
0.0000
57
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Chlorobenzene
Results from the GC/MS analysis
Com ponent Nam e
Chlorbenzol_112
Sam ple Nam e
0_2
0_6
1_0
1_5
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
Area
2916559
8112781
13342125
18268178
394526
256668
95310
882354
1103765
108782
1398904
3618440
147820
Equation
Y = 433420+1.22644e+007*X R^2 = 0.9954
Standards
Know Conc Calculated Conc
0.200
0.202
0.600
0.626
1.000
1.053
1.500
1.454
0.000
0.000
0.000
0.037
0.055
0.000
0.079
0.260
0.000
%Diff
1%
4%
5%
-3%
%RSD
0.0%
0.0%
0.0%
0.0%
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
1
2
3
Time
10.07.2012 10:45
10.07.2012 12:45
10.07.2012 14:45
0.3
Reactor
Time since start [h] eff. Conc [mg/l]
0:00
0.00
2:00
0.04
4:00
0.08
Tim e vs Concentration, Mass
Trap 1
Sample Nr.
eff. Conc [mg/l]
Trap Volume 1 [ml]
Mass [mg]
1
0.00
20.00
2
0.16
18.00
3
0.48
17.00
Trap 2
eff. Conc [mg/l]
Trap Volume 1 [ml] Mass [mg]
0.00
0.00
20.00
0.00
0.00
18.00
0.01
0.05
16.00
0.00
0.00
0.00
Current efficiencies
Current efficiency [μg/C]
[C]
Reactor
Gas
3645.63
3.01E-03
3057.45
4.13E-03
6703.08
3.52E-03
C_trap 2
3.00E-04
1.21E-03
7.10E-04
C_g,out
0.00
0.00
0.00
0.0000
0.0000
0.0000
58
Appendix: Formation of chlorinated organics during electrolytic urine treatment
9.2.
Data - Experiment Eup_G2
Dichloromethane
Results from the GC/MS analysis
Com ponent Nam e
Dichlormethan_84
Sam ple Nam e
0_2
0_6
1_0
1_5
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_l
4_ga
4_gb
5_l
5_l_s
5_ga_1
5_ga_2
5_gb_1
5_gb_2
6_l
6_l_s
6_ga_1
6_ga_2
6_gb_1
6_gb_2
7_l
7_ga_1
7_ga_2
7_gb_1
7_gb_2
Area
689209
1741558
2774160
3792528
46047
197525
187152
52600
138924
173300
46541
122645
193043
45208
119479
157524
93517
81950
701130
355611
340179
298368
90459
51041
822751
397715
534442
379543
81953
826669
398888
576046
295797
Equation
Y = 137202+2.51862e+006*X R^2 = 0.9937
Standards
Know Conc Calculated Conc
0.200
0.219
0.600
0.637
1.000
1.047
1.500
1.451
0.000
0.000
0.000
0.000
0.001
0.000
0.000
0.000
0.000
0.000
0.000
0.008
0.000
0.000
0.224
0.087
0.081
0.064
0.000
0.000
0.272
0.103
0.158
0.096
0.000
0.274
0.104
0.174
0.063
%Diff
10%
6%
5%
-3%
%RSD
0.0%
0.0%
0.0%
0.0%
Dilusion
assume
high
low
Dillusion
5
Reaktor
1st extraction
2nd extraction
Average
Trap 1
1
2
Average
Trap 2
1
2
Average
best range
6
0.00
0.00
0.00
0.22
0.17
0.20
0.08
0.13
0.10
7
0.00
0.00
0.00
0.27
0.21
0.24
0.16
0.19
0.18
0.00
0.00
0.27
0.21
0.24
0.17
0.13
0.15
59
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
1
2
3
4
5
6
7
Time
12.07.2012 10:48
12.07.2012 12:30
12.07.2012 14:45
12.07.2012 17:00
13.07.2012 09:00
13.07.2012 13:00
13.07.2012 16:00
0.3
Reactor
Time since start [h] eff. Conc [mg/l]
0:00
0.00
1:42
0.00
3:57
0.00
6:12
0.00
22:12
0.00
26:12
0.00
29:12
0.00
Tim e vs Concentration, Mass
Trap 1
Sample Nr.
eff. Conc [mg/l]
Trap Volume 1 [ml]
Mass [mg]
1
0.00
82.00
2
0.00
80.36
3
0.00
78.72
4
0.00
77.08
5
0.20
75.44
6
0.24
73.59
7
0.24
71.14
0.00
0.00
0.00
0.00
14.99
17.63
17.13
Mass [mg]
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Trap 2
eff. Conc [mg/l]
Trap Volume 2 [ml] Mass [mg]
0.00
82.00
0.00
80.77
0.00
79.54
0.01
77.90
0.10
76.26
0.18
74.41
0.15
71.95
0.00
0.00
0.00
0.63
7.95
13.03
10.80
Current efficiencies
Current efficiency [μg/C]
transferred charge [C]
Reactor
1'514
1'882
1'781
14'962
3'730
2'971
26'840
[µg/C]
Gas [µg/C]
C_trap 2 [mg/l]
0.00E+00
0.00E+00
0.00E+00
0.00E+00
0.00E+00
3.85E-04
0.00E+00
1.87E-03
0.00E+00
3.16E-03
0.00E+00
4.53E-04
0.00E+00
1.55E-03
0.00
0.00
0.00
0.06
0.14
0.16
0.06
C_g,out [mg/l]
0.0000
0.0000
0.0000
0.0002
0.0005
0.0006
0.0002
60
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Trichloromethane
Results from the GC/MS analysis
Com ponent Nam e
Chloroform_83
Sam ple Nam e
0_2
0_6
1_0
1_5
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_l
4_ga
4_gb
5_l
5_l_s
5_ga_1
5_ga_2
5_gb_1
5_gb_2
6_l
6_l_s
6_ga_1
6_ga_2
6_gb_1
6_gb_2
7_l
7_ga_1
7_ga_2
7_gb_1
7_gb_2
Area
2009373
4758748
7095747
9794048
159279
36943
36806
149060
69369
36038
169938
123830
42993
209018
221632
51841
278510
158237
1749597
887447
462855
316864
269624
153919
2068102
1010135
661536
408087
293533
2275059
1105975
849521
447057
Equation
Y = 503585+6.40606e+006*X R^2 = 0.9900
Standards
Know Conc Calculated Conc
0.200
0.235
0.600
0.664
1.000
1.029
1.500
1.450
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.195
0.060
0.000
0.000
0.000
0.000
0.244
0.079
0.025
0.000
0.000
0.277
0.094
0.054
0.000
%Diff
18%
11%
3%
-3%
%RSD
0.0%
0.0%
0.0%
0.0%
Dilusion
assume
high
low
Dillusion
5
Reaktor
1st extraction
2nd extraction
Average
Trap 1
1
2
Average
Trap 2
1
2
Average
best range
6
0.00
0.00
0.00
0.19
0.12
0.16
0.00
0.00
0.00
7
0.00
0.00
0.00
0.24
0.16
0.20
0.02
0.00
0.01
0.00
0.00
0.28
0.19
0.23
0.05
0.00
0.03
61
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
1
2
3
4
5
6
7
Time
12.07.2012 10:48
12.07.2012 12:30
12.07.2012 14:45
12.07.2012 17:00
13.07.2012 09:00
13.07.2012 13:00
13.07.2012 16:00
0.3
Reactor
Time since start [h] eff. Conc [mg/l]
0:00
0.00
1:42
0.00
3:57
0.00
6:12
0.00
22:12
0.00
26:12
0.00
29:12
0.00
Tim e vs Concentration, Mass
Trap 1
Sample Nr.
eff. Conc [mg/l]
Trap Volume 1 [ml]
Mass [mg]
1
0.00
82.00
2
0.00
80.36
3
0.00
78.72
4
0.00
77.08
5
0.16
75.44
6
0.20
73.59
7
0.23
71.14
0.00
0.00
0.00
0.00
11.86
14.80
16.52
Mass [mg]
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Trap 2
eff. Conc [mg/l]
Trap Volume 2 [ml] Mass [mg]
0.00
82.00
0.00
80.77
0.00
79.54
0.00
77.90
0.00
76.26
0.01
74.41
0.03
71.95
0.00
0.00
0.00
0.00
0.00
0.92
1.94
Current efficiencies
Current efficiency [μg/C]
transferred charge [C] Reactor
1'514
1'882
1'781
14'962
3'730
2'971
26'840
[µg/C]
Gas [µg/C]
C_trap 2 [mg/l]
0.00E+00
0.00E+00
0.00E+00
0.00E+00
0.00E+00
0.00E+00
0.00E+00
7.93E-04
0.00E+00
1.13E-03
0.00E+00
1.15E-03
0.00E+00
7.60E-04
0.00
0.00
0.00
0.00
0.01
0.02
0.01
C_g,out [mg/l]
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
62
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Tretrachloromethane
Results from the GC/MS analysis
Com ponent Nam e
Tetrachlormethan_117
Sam ple Nam e
0_2
0_6
1_0
1_5
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_l
4_ga
4_gb
5_l
5_l_s
5_ga_1
5_ga_2
5_gb_1
5_gb_2
6_l
6_l_s
6_ga_1
6_ga_2
6_gb_1
6_gb_2
7_l
7_ga_1
7_ga_2
7_gb_1
7_gb_2
Area
1218869
3177951
5622082
8105331
71531
70374
68905
38110
69023
58206
71320
76595
377978
225147
33723
63848
54515
82357
481273
270709
83473
81334
72908
530160
291634
108955
82310
Equation
Y = 51955.8+5.41347e+006*X R^2 = 0.9988
Standards
Know Conc Calculated Conc
0.200
0.216
0.600
0.577
1.000
1.029
1.500
1.488
0.004
N/A
0.000
N/A
0.000
0.003
N/A
0.000
N/A
0.000
0.003
0.000
N/A
0.000
0.003
0.001
N/A
0.000
0.004
0.005
0.060
0.032
0.000
0.002
0.000
0.006
0.079
0.040
0.006
0.005
0.004
0.088
0.044
0.011
0.006
%Diff
8%
-4%
3%
-1%
%RSD
0.0%
0.0%
0.0%
0.0%
N/A
N/A
N/A
N/A
N/A
N/A
Dilusion
assume
high
low
Dillusion
5
Reaktor
1st extraction
2nd extraction
Average
Trap 1
1
2
Average
Trap 2
1
2
Average
best range
6
0.00
0.00
0.00
0.06
0.06
0.06
0.00
0.00
0.00
7
0.00
0.01
0.00
0.08
0.08
0.08
0.01
0.01
0.01
0.00
0.00
0.09
0.09
0.09
0.01
0.01
0.01
63
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
1
2
3
4
5
6
7
Time
12.07.2012 10:48
12.07.2012 12:30
12.07.2012 14:45
12.07.2012 17:00
13.07.2012 09:00
13.07.2012 13:00
13.07.2012 16:00
0.3
Reactor
Time since start [h] eff. Conc [mg/l]
0:00
0.004
1:42
0.003
3:57
0.003
6:12
0.003
22:12
0.004
26:12
0.004
29:12
0.004
Tim e vs Concentration, Mass
Trap 1
Sample Nr.
eff. Conc [mg/l]
Trap Volume 1 [ml]
Mass [mg]
1
0.00
82.00
2
0.00
80.36
3
0.00
78.72
4
0.00
77.08
5
0.06
75.44
6
0.08
73.59
7
0.09
71.14
0.00
0.00
0.09
0.09
4.69
5.89
6.29
Mass [mg]
0.001
0.001
0.001
0.001
0.001
0.001
0.001
Trap 2
eff. Conc [mg/l]
Trap Volume 2 [ml] Mass [mg]
0.00
82.00
0.00
80.77
0.00
79.54
0.00
77.90
0.00
76.26
0.01
74.41
0.01
71.95
0.00
0.00
0.00
0.00
0.17
0.62
0.78
Current efficiencies
Current efficiency [μg/C]
transferred charge [C] Reactor
1'514
1'882
1'781
14'962
3'730
2'971
26'840
[µg/C]
Gas [µg/C]
C_trap 2 [mg/l]
0.00E+00
0.00E+00
0.00E+00
4.83E-05
0.00E+00
0.00E+00
0.00E+00
3.20E-04
0.00E+00
4.85E-04
0.00E+00
2.76E-04
0.00E+00
2.89E-04
0.00
0.00
0.00
0.00
0.01
0.01
0.00
C_g,out [mg/l]
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
64
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Chlorobenzene
Results from the GC/MS analysis
Com ponent Nam e
Chlorbenzol_112
Sam ple Nam e
0_2
0_6
1_0
1_5
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_l
4_ga
4_gb
5_l
5_l_s
5_ga_1
5_ga_2
5_gb_1
5_gb_2
6_l
6_l_s
6_ga_1
6_ga_2
6_gb_1
6_gb_2
7_l
7_ga_1
7_ga_2
7_gb_1
7_gb_2
Area
1897350
5442894
9726068
14728379
65172
309771
107217
816574
303936
1648514
619970
922602
12630053
6236542
265263
147235
660894
16833061
8767747
349178
221087
608367
20123736
9760553
418617
227556
Equation
Y = -133160+9.83651e+006*X R^2 = 0.9990
Standards
Know Conc Calculated Conc
0.200
0.206
0.600
0.567
1.000
1.002
1.500
1.511
N/A
0.000
N/A
0.000
0.020
0.045
0.024
N/A
0.000
0.097
0.044
N/A
0.000
0.181
0.077
N/A
0.000
0.107
N/A
0.000
1.298
0.648
0.041
0.029
0.081
N/A
0.000
1.725
0.905
0.049
0.036
0.075
2.059
1.006
0.056
0.037
%Diff
3%
-6%
0%
1%
N/A
N/A
%RSD
0.0%
0.0%
0.0%
0.0%
N/A
N/A
N/A
N/A
N/A
Dilusion
assume
high
low
Dillusion
5
Reaktor
1st extraction
2nd extraction
Average
Trap 1
1
2
Average
Trap 2
1
2
Average
best range
6
0.11
0.00
0.05
1.30
1.30
1.30
0.04
0.06
0.05
7
0.08
0.00
0.04
1.72
1.81
1.81
0.05
0.07
0.06
0.08
0.08
2.06
2.01
2.01
0.06
0.07
0.06
65
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Calculated concentrations and masses.
Tim e vs Concentration, Mass
Sample Nr.
1
2
3
4
5
6
7
Time
12.07.2012 10:48
12.07.2012 12:30
12.07.2012 14:45
12.07.2012 17:00
13.07.2012 09:00
13.07.2012 13:00
13.07.2012 16:00
0.3
Reactor
Time since start [h] eff. Conc [mg/l]
0:00
0.00
1:42
0.05
3:57
0.10
6:12
0.18
22:12
0.11
26:12
0.08
29:12
0.08
Tim e vs Concentration, Mass
Trap 1
Sample Nr.
eff. Conc [mg/l]
Trap Volume 1 [ml]
Mass [mg]
1
0.00
82.00
2
0.04
80.36
3
0.08
78.72
4
0.08
77.08
5
1.30
75.44
6
1.81
73.59
7
2.01
71.14
0.00
3.57
6.03
5.90
97.79
133.18
143.10
Mass [mg]
0.00
0.01
0.03
0.05
0.03
0.02
0.02
Trap 2
eff. Conc [mg/l]
Trap Volume 2 [ml] Mass [mg]
0.00
82.00
0.00
80.77
0.00
79.54
0.00
77.90
0.05
76.26
0.06
74.41
0.06
71.95
0.00
0.00
0.00
0.00
3.72
4.50
4.66
Current efficiencies
Current efficiency [μg/C]
transferred charge [C] Reactor
1'514
1'882
1'781
14'962
3'730
2'971
26'840
[µg/C]
Gas [µg/C]
C_trap 2 [mg/l]
8.92E-03
2.36E-03
8.21E-03
1.34E-03
1.42E-02
0.00E+00
-1.48E-03
6.41E-03
-2.14E-03
1.04E-02
-5.39E-04
4.96E-03
8.43E-04
5.96E-03
0.00
0.00
0.00
0.02
0.05
0.06
0.02
C_g,out [mg/l]
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
66
Appendix: Formation of chlorinated organics during electrolytic urine treatment
9.3.
Data - Experiment Elow_G1
Dichloromethane
Results from the GC/MS analysis
Com ponent Nam e
Dichlormethan_84
Sam ple Nam e
0_2
0_6
1_0
1_5
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_l
4_ga
4_gb
5_l
5_ga
5_gb
6_l
6_ga_1
6_ga_2
6_gb_1
6_gb_2
Area
929882
2605564
3810144
6115478
63453
104027
122236
44300
43992
69283
54098
47722
33605
46237
23696
13051
9510
26501
8900
6461
30126
13048
5711
12584
Equation
Y = 26297.5+4.32069e+006*X R^2 = 0.9993
Standards
Know Conc Calculated Conc
0.200
0.209
0.600
0.597
1.000
0.876
1.500
1.409
0.009
0.000
0.000
0.004
0.004
0.010
0.006
0.005
0.002
0.005
0.000
0.000
0.000
0.000
0.000
0.000
0.001
0.000
0.000
0.000
%Diff
5%
-1%
-12%
-6%
%RSD
0.0%
0.0%
0.0%
0.0%
Trichloromethane
Results from the GC/MS analysis
Com ponent Nam e
Chloroform_83
Sam ple Nam e
0_2
0_6
1_0
1_5
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_l
4_ga
4_gb
5_l
5_ga
5_gb
6_l
6_ga_1
6_ga_2
6_gb_1
6_gb_2
Area
1892888
5322607
8672094
12684164
107096
68461
55710
75518
71406
50349
69986
98513
56720
74574
83955
53247
38250
177146
111782
27688
150601
71985
103060
61446
Equation
Y = 86017.2+8.63529e+006*X R^2 = 0.9996
Standards
Know Conc Calculated Conc
0.200
0.209
0.600
0.606
1.000
0.994
1.500
1.459
0.002
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.011
0.003
0.000
0.007
0.000
0.002
0.000
%Diff
5%
1%
-1%
-3%
%RSD
0.0%
0.0%
0.0%
0.0%
67
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Tretrachloromethane
Results from the GC/MS analysis
Com ponent Nam e
Tetrachlormethan_117
Sam ple Nam e
0_2
0_6
1_0
1_5
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_l
4_ga
4_gb
5_l
5_ga
5_gb
6_l
6_ga_1
6_ga_2
6_gb_1
6_gb_2
Area
1224817
3538276
5861254
9226619
18395
15724
10597
15463
18987
13527
12666
27320
14963
15200
22834
13744
8712
39854
21824
7414
33742
17220
22915
14634
Equation
Y = -50549.1+6.09203e+006*X R^2 = 0.9989
Standards
Know Conc Calculated Conc
0.200
0.209
0.600
0.589
1.000
0.970
1.500
1.523
0.011
0.011
0.010
0.011
0.011
0.011
0.010
0.013
0.011
0.011
0.012
0.011
0.010
0.015
0.012
0.010
0.014
0.011
0.012
0.011
%Diff
5%
-2%
-3%
2%
%RSD
0.0%
0.0%
0.0%
0.0%
Chlorobenzene
Results from the GC/MS analysis
Com ponent Nam e
Chlorbenzol_112
Sam ple Nam e
0_2
0_6
1_0
1_5
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_l
4_ga
4_gb
5_l
5_ga
5_gb
6_l
6_ga_1
6_ga_2
6_gb_1
6_gb_2
Area
2464006
6692606
12038515
18589339
167347
204948
155398
153233
727120
140191
131469
1203171
171975
138008
1568991
152092
77051
3983220
695185
80941
4699940
2349806
928320
514754
Equation
Y = -191390+1.23459e+007*X R^2 = 0.9981
Standards
Know Conc Calculated Conc
0.200
0.215
0.600
0.558
1.000
0.991
1.500
1.521
0.029
0.032
0.028
0.028
0.074
0.027
0.026
0.113
0.029
0.027
0.143
0.028
0.022
0.338
0.072
0.022
0.396
0.206
0.091
0.057
%Diff
8%
-7%
-1%
1%
%RSD
0.0%
0.0%
0.0%
0.0%
68
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Current efficiencies
Current efficiency [μg/C]
transferred charge [C] Reactor [µg/C]
Gas [µg/C]
428
0.00
3.16E-03
1'683
0.00
6.28E-04
166
0.00
1.89E-02
2'559
0.00
2.37E-03
9.4.
Data - Experiment Eup_BDD1
Dichloromethane
Results from the GC/MS analysis
Com ponent Nam e
Dichlormethan_84
Sam ple Nam e
0_2
0_6
1_0
1_5
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_l
4_ga
4_gb
5_l
5_ga_1
5_ga_2
5_gb_1
5_gb_2
6_l
6_ga_1
6_ga_2
6_ga_4
6_gb_1
6_gb_2
6_gb_4
Area
750139
1784046
2918437
4529709
25511
52120
57355
2419656
5718919
2054927
362632
481040
379743
160827
326304
202565
60429
129542
63573
24793
86111
164074
114578
74976
64852
24360
48219
73539
Equation
Y = 48247.6+2.95185e+006*X R^2 = 0.9980
Standards
Know Conc Calculated Conc
0.200
0.238
0.600
0.588
1.000
0.972
1.500
1.518
0.000
0.001
0.003
0.803
1.921
0.680
0.107
0.147
0.112
0.038
0.094
0.052
0.004
0.028
0.005
0.000
0.013
0.039
0.022
0.009
0.006
0.000
0.000
0.009
%Diff
19%
-2%
-3%
1%
%RSD
0.0%
0.0%
0.0%
0.0%
69
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Trichloromethane
Results from the GC/MS analysis
Com ponent Nam e
Chloroform_83
Sam ple Nam e
0_2
0_6
1_0
1_5
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_l
4_ga
4_gb
5_l
5_ga_1
5_ga_2
5_gb_1
5_gb_2
6_l
6_ga_1
6_ga_2
6_ga_4
6_gb_1
6_gb_2
6_gb_4
Area
1600540
4317020
6828572
9921794
133390
108099
86035
16866186
15775098
4429312
1464133
918812
624987
721276
638773
378349
243482
200750
116049
69484
103711
181498
134726
135053
101637
44709
72110
91364
Equation
Y = 201998+6.56301e+006*X R^2 = 0.9984
Standards
Know Conc Calculated Conc
0.200
0.213
0.600
0.627
1.000
1.010
1.500
1.481
0.000
0.000
0.000
2.539
2.373
0.644
0.192
0.109
0.064
0.079
0.067
0.027
0.006
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
%Diff
7%
5%
1%
-1%
%RSD
0.0%
0.0%
0.0%
0.0%
%Diff
3%
0%
1%
0%
%RSD
0.0%
0.0%
0.0%
0.0%
Tretrachloromethane
Results from the GC/MS analysis
Com ponent Nam e
Tetrachlormethan_117
Sam ple Nam e
0_2
0_6
1_0
1_5
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_l
4_ga
4_gb
5_l
5_ga_1
5_ga_2
5_gb_1
5_gb_2
6_l
6_ga_1
6_ga_2
6_ga_4
6_gb_1
6_gb_2
6_gb_4
Area
1276079
3602563
5989047
8852337
46650
63247
65375
17854219
17170604
4297051
976051
578849
384543
431508
376087
186225
127573
86557
63239
34165
72848
87885
64756
96519
54244
44819
51607
60658
Equation
Y = 57049.8+5.88933e+006*X R^2 = 0.9998
Standards
Know Conc Calculated Conc
0.200
0.207
0.600
0.602
1.000
1.007
1.500
1.493
0.000
0.001
0.001
3.022
2.906
0.720
0.156
0.089
0.056
0.064
0.054
0.022
0.012
0.005
0.001
0.000
0.003
0.005
0.001
0.007
0.000
0.000
0.000
0.001
70
Appendix: Formation of chlorinated organics during electrolytic urine treatment
Chlorobenzene
Results from the GC/MS analysis
Com ponent Nam e
Chlorbenzol_112
Sam ple Nam e
0_2
0_6
1_0
1_5
1_l
1_ga
1_gb
2_l
2_ga
2_gb
3_l
3_ga
3_gb
4_l
4_ga
4_gb
5_l
5_ga_1
5_ga_2
5_gb_1
5_gb_2
6_l
6_ga_1
6_ga_2
6_ga_4
6_gb_1
6_gb_2
6_gb_4
Area
2663530
7678539
12945261
19867845
289056
202678
222888
4395215
8862117
4253511
537703
2062749
808466
354890
2725233
611699
371603
7491252
3997435
1167919
698096
297381
9132581
5022938
2497429
1594054
878869
541976
Equation
Y = -69326.3+1.31824e+007*X R^2 = 0.9996
Standards
Know Conc Calculated Conc
0.200
0.207
0.600
0.588
1.000
0.987
1.500
1.512
0.027
0.021
0.022
0.339
0.678
0.328
0.046
0.162
0.067
0.032
0.212
0.052
0.033
0.574
0.309
0.094
0.058
0.028
0.698
0.386
0.195
0.126
0.072
0.046
%Diff
4%
-2%
-1%
1%
%RSD
0.0%
0.0%
0.0%
0.0%
Current efficiency (exclude sample point 2)
Current efficiency [μg/C]
transferred charge Reactor [μg/C]
Gas [μg/C]
C_trap 2 [mg/l]
C_g,out [mg/l]
3'546
5.34E-05
3.48E-03
0.07
0.0000
71
Appendix: Formation of chlorinated organics during electrolytic urine treatment
9.5.
Comparison
9.5.1. Experiment Eup_G1
Figure 14: Experiment Eup_G1: Formation of chlorinated organics in electrolytic treatment of stored
urine. Graphite anode and cathode. Applied potential: 1.3V vs. MSE. 300ml of stored urine. Evolving gas
sucked through two traps of 20ml dodecane each (gas flow: 1.82l/h). Data points with gray / orange box:
concentration lower / higher than calibration area  high uncertainty.
9.5.2. Experiment Eup_G2
Figure 15: Experiment Eup_G2: Formation of chlorinated organics in electrolytic treatment of stored
urine. Graphite anode and cathode. Applied potential: 1.3V vs. MSE. 300ml of stored urine. Evolving gas
sucked through two traps of 82ml dodecane each (gas flow: 1.74l/h). Data points with gray box: concentration
lower than calibration area  high uncertainty.
72
Appendix: Formation of chlorinated organics during electrolytic urine treatment
9.5.3. Experiment Elow_G1
Figure 16: Experiment Elow_G1: Formation of chlorinated organics in electrolytic treatment of stored
urine. Graphite anode and cathode. Applied potential: 0.8V vs. MSE. 300ml of stored urine. Evolving gas
sucked through two traps of 20ml dodecane each (gas flow: 1.73l/h). Data points with gray box: concentration
lower than calibration area  high uncertainty.
73
Appendix: Formation of chlorinated organics during electrolytic urine treatment
10.
Concentration (mg/l): Ammonia, nitrate, nitrite, chloride, chlorine, phosphate, sulphate and COD
Uup_G1
Time
Time since start [h] Transferred charge [C] Ammonia
free chlorine Total Chlorine
Bound Chlorine
10.07.2012 10:45
0:00
0
2980
1
1.14
0.14
10.07.2012 12:45
2:00
3'646
2730
5.23
8.17
2.94
10.07.2012 14:45
4:00
6'703
Chloride
Nitrite
3432
0.22
Total N
0
0.92
3103
Nitrate
1.7
2980.22
34
2764.92
73
2634.7
Phosphate
Sulphate
214
696
26.3 (T=24.3°C)
743
27.3 (T=25.3°C)
2560
6.5
16.7
10.2
Removal / Production [mg/h]:
-105.00
1.38
3.89
2.52
-82.25
0.37
18.25
-86.38
250
9.00
11.75
Removal / Production [mg/C]:
-0.06
0.0008
0.0023
0.0015
-0.05
0.00
0.01
-0.05
0.01
0.01
free chlorine Total Chlorine
Bound Chlorine
Conductivity [mS/cm2]
Uup_G2
Time
Time since start [h] Transferred charge [C] Ammonia
Chloride
Nitrite
Nitrate
Total N
Phosphate
Sulphate
3495
0.24
0
2870.24
221
705
0.99
0.76
15.8
2966.56
3.91
1.33
1.01
41.6
2892.61
2.93
1.12
1.18
70.5
2871.68
1.50
2.81
1.31
18
344
2392.00
1880.00
1.11
2.36
1.25
22.7
392
2294.70
1800.00
0.94
2.37
1.43
27.3
432
2259.30
218
823
Removal / Production [mg/h]:
-36.74
0.03
0.06
0.03
-12.43
0.93
14.84
-20.98
-0.10
4.05
Removal / Production [mg/C]:
-0.04
0.0000
0.0001
0.00003
-0.01
0.00
0.02
-0.02
0.00
0.00
free chlorine Total Chlorine
Bound Chlorine
12.07.2012 10:48 0:00
0
2870.00
0.00
0.54
0.54
12.07.2012 12:30 1:42
1'514
2950.00
3.02
4.01
12.07.2012 14:45 3:57
3'396
2850.00
2.58
12.07.2012 17:00 6:12
5'178
2800.00
1.81
13.07.2012 09:00 22:12
20'140
2030.00
13.07.2012 13:00 26:12
23'870
13.07.2012 16:00 29:12
26'840
3133
Conductivity [mS/cm2]
26.4 (T=23.5°C)
Uup_BDD1
Time
Time since start [h] Transferred charge [C] Ammonia
17.07.2012 11:00 0:00
0
2690.00
0.51
0
-0.51
17.07.2012 12:45 1:45
278
2620.00
1.37
2.07
17.07.2012 15:00 4:00
461
2620.00
2.32
3.62
17.07.2012 17:00 6:00
662
2570.00
2.59
18.07.2012 09:00 22:00
3'028
2340.00
18.07.2012 13:00 26:00
3'546
Chloride
3462
Nitrite
Nitrate
Total N
Phosphate
COD [mg/l]
724
Conductivity [mS/cm2]
0
2690.25
0.7
0.32
0
2620.32
4461.00
1.3
0.36
0
2620.36
4476.00
3.49
0.9
0.37
0
2570.37
4362.00
1.20
1.88
0.68
0.88
3.0
2343.88
2260.00
1.08
1.92
0.84
0.95
3.0
2263.95
Removal / Production [mg/h]:
-16.54
0.02
0.07
0.05
-0.23
0.03
0.12
Removal / Production [mg/C]:
-0.12
0.00
0.00
0.00038
-0.002
0.00
0.00
free chlorine Total Chlorine
Bound Chlorine
3456
226
Sulphate
0.25
4402.00 25.7 (T=24.5°c)
3899.00
220
843
-16.40
-0.23
4.58
-0.12
0.00
0.03
3807.00
-22.88 tot. Removed COD [mg]:
-0.17
595.00
Ulow _G1
Time
Time since start [h] Transferred charge [C] Ammonia
19.07.2012 11:00 0:00
0
2590
0.52
0.61
0.09
19.07.2012 13:00 2:00
243
2610
0.89
1.47
19.07.2012 15:00 4:00
429
2470
1.86
2.63
19.07.2012 17:15 6:15
712
2290
2.14
20.07.2012 09:00 22:00
2'395
2340
20.07.2012 13:00 26:00
2'560
Chloride
3384
Nitrite
Nitrate
Total N
Phosphate
220
Sulphate
0.132
0
2590.132
0.58
0.241
0
2610.241
0.77
0.397
0
2470.397
2.88
0.74
0.497
0
2290.497
1.46
2.21
0.75
0.147
10.5
2350.647
2230
1.13
1.87
0.74
3560
0.16
14
2244.16
242
900
Removal / Production [mg/h]:
-13.85
0.02
0.05
0.03
6.77
0.00
0.54
-13.31
0.85
7.31
Removal / Production [mg/C]:
-0.14
0.00
0.00
0.00025
0.07
0.00
0.01
-0.14
0.01
0.07
Conductivity [mS/cm2]
710 25.6 (T=24.9°C)
74