DESIGN AND CONSTRUCTION OF AN EXPERIMENTAL SETUP FOR MEASURING INTRINSIC
KINETICS OF BIOMASS FAST PYROLYSIS
Diana C. Vargas a,b, Hilal Ezgi Toraman a, Hans-Heinrich Carstensen a, Daniela Almeida Streitwieser b,
Kevin M. Van Geem a* and Guy B. Marin a
a Ghent
University, Laboratory for Chemical Technology, Technologiepark 914, 9052 Gent, Belgium
http://www.lct.UGent.be
b Laboratorio de Desarrollo de Energías Alternativas, Departamento de Ingeniería Química, Universidad San Francisco de Quito,
Casilla Postal: 17-12-841, Quito, Ecuador
*E-mail: [email protected]
European Research Institute of Catalysis
Motivation of the study
Introduction
Lignin: Complex polymer of p-coumaryl alcohol, coniferyl alcohol,
and sinapyl alcohol
Non-condensable gases
Bio char
Decomposition pathways
Bio oil
Fuels and chemicals
Pyrolysis
Biomass
- the most abundant type of renewable biomass
- not competing with the food chain
O
H
H

or
H
H
H
H
- Second reactor: isothermal region with
step gradients at the ends clearly
defines the reaction zone.
+ CO
OH
OH
OH
O
OH
+ CO
•
•+ H + CO
+ 2H + CO
Resorcinol: Analogous to catechol and hydroquinone ???
OH
OH
O
+ CO2
+ 2H + CO
Expected
Tandem Micro-pyrolyzer setup
OH
Reported
Vaporization profiless
Optimized step-wise heating of the
sample in the first reactor provides
almost constant fuel inlet
concentrations for the second
reactor for several minutes
=> semi-batch / plug flow
Pyrolysis
Cryo-trap
Refocusing of
components
GC×GC –
FID/TOF-MS
Purpose:
• comprehensive analysis of fast pyrolysis product distribution of polymers incl. biomass
o close mass and elementary balances
• determination of intrinsic rate coefficients for solid to gas transition
o avoid transport limitations
o isothermal conditions
• investigation of gas-phase reactions of expensive solid model substances
o small sample sizes
•Solid
• Two stage reactor
• Solid, liquid or gas samples
• Isothermal, linear and stepwise
temperature profiles
• Large T-range: 40 - 900 0C
• Multi-shot sample introduction
• Cryo-trap for fast injection
50 g/cup
resorcinol
200 g/cup
glass wool
cup size
Resorcinol
Experiments require very small amounts of substance
Gas phase pyrolysis
Solid to gas chemistry
- 1st reactor
- 1st reactor:
100 → 140 → 230°C
800°C, 500°C, 350°C
steady release of
- No 2nd reactor
resorcinol
- Carrier flow rate
- 2nd reactor
50 mL/min
- Cryo-trap: 1 min @ -1960C 820°C - 830°C - 850°C
- Carrier flow rate:
50 mL/min
- Cryo-trap: 7 min @ 0C
196
decomposition
Product distribution of resorcinol solid chemistry include small hydrocarbons ranging from CH4 to
large polyaromatic hydrocarbons.
-
Char formation during pyrolysis indicates that
reactions take place in the condensed phase
GC×GC - FID/TOF-MS
• Simultaneous identification
and quantification
• High sensitivity TOF-MS with
soft ionization feature
Customized Trace GC 1310
with 3 Detectors
TCD-1
Water, formaldehyde
TCD-2 and PDD
permanent gases incl. H2
C2- components
resorcinol
Experimental details
-
Analytics section
Micro-pyrolyzer
2nd Reactor
1st Reactor
OH
OH
Customized
Trace GC 1310
H


Catechol and Hydroquinone decomposition (major
pathway); analogous to phenol
OH
Tandem Micro-pyrolyzer setup
• Intrinsic kinetic studies
• Well-defined temperature

H
H
H
Bio oil – highest potential for commercialization
– yield and quality control requires understanding of the chemistry
Previous studies:
• TGA experiments
• Non-isothermal conditions

O
O

O
O
- Temperature profiles obtained for both
reactors at experimental conditions.
- Highest temperature in the first reactor
coincides with location of dropped cup
Phenol decomposition (major pathway)
OH
Lignocellulosic biomass
substituted phenols and phenyl ethers
Model compounds of interest
Temperature profiles in the
reactors
Temperature [ᴼC]
800
500
350
Char [%]
14.2
23.3
-2.6
TOF- Chromatogram for the thermal decomposition of
resorcinol using the 1st reactor at 800°C
Gas phase resorcinol decomposition
-
Major resorcinol pyrolysis products are cyclopentadiene and its subsequent reaction products (e.g.
naphthalene, indene).
CO2 detected but also as background molecule
No evidence for cyclopentadienone formation
Concentration profiles are consistent with reported special chemistry
Comprehensive 2D
Gas Chromatography
Conclusions
Plug flow regime
 New micro-pyrolyzer successfully used to study solid
and gas phase chemistry of a lignin model compound
 Fast heating of solid resorcinol to high temperatures
initiates chemical transformations in the condensed
phase
 Substantial amounts of char formed
 Gas phase pyrolysis of resorcinol yields cyclopentadiene
 Confirmation of the results by Scheer et al.
Future work
 Repeat resorcinol experiments to obtain
comprehensive quantitative data
 Develop elementary step kinetic models able
to quantitatively describe the gas phase data
 Extend study to phenol, catechol,
hydroquinone, syringol, guaiacol, other lignin
model compounds.
Acknowledgements
This research has been supported by the Belgian Development Cooperation through
VLIR-UOS. VLIR-UOS supports partnerships between universities and university colleges
in Flanders (Belgium) and the South looking for innovative responses to global and local
challenges. Visit www.vliruos.be for more information. The research leading to these
results has received funding from the European Research Council under the European
Union’s Seventh Framework Programme (FP7/2007-2013) / ERC grant agreement n°
290793. The SBO proposal “Bioleum” supported by the Institute for promotion of
Innovation through Science and Technology in Flanders (IWT) is acknowledged.
Cascatbel Workshop 2016, Chalkidiki, Greece, May 18-20 , 2016