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Paper 84
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SYNTHESIS OF GREEN POLYETHYLENE FROM SUGARCANE-BASED
ETHANOL
Nicholas Waters, [email protected], 1PM Mena, Nicolas Valvo, [email protected], 1PM Mena
Abstract— Plastic plays a large role in everyday life
and is used to make anything from cellphones, to car parts, to
containers and bags. The main polymer that makes plastic
production possible is polyethylene. Currently, conventional
polyethylene is derived from the cracking of fossil-based raw
materials (natural gas and naphtha/oil), a nonrenewable
resource. However, there exists an alternative pathway to
polyethylene through dehydration of ethanol. Ethanol can be
derived from organic biomass. This paper will investigate the
viability of polyethylene made from this renewable source. It
will discuss the advantages, such as low carbon footprints,
and disadvantages, such as lower yields or higher energy
intake. In addition, the sustainability of the process will be
investigated by breaking down each step of production.
Overall, conclusions will be drawn about which is the best
source for renewable polyethylene and the sustainability
content will be interpreted to understand how and why it is a
better alternative to fossil based polyethylene.
Created Using ChemDraw
Its structure consists of repeated chains of two carbon
atoms and while it is very simple, it’s uses are endless.
Polyethylene is essentially plastic. Plastic makes up a number
of things ranging from cellphones, to containers, to car parts,
and much more. There are a few types of polyethylene and
their intermolecular structure affects their properties. That is
how plastic can be found in anything from wispy thin plastic
bags to hard packed car parts. While the grades can change
drastically, it all comes back to that basic structure of two
repeated carbon atoms. Polyethylene is currently produced at
a rate of over 60 million tons per year, making it the most used
polymer in the world [1].
The Arising Problem with Polyethylene
The main way polyethylene is produce currently is
through cracking of fossil fuels, a nonrenewable resource. It
will be addressed later, but the main way this occurs is by
reducing ingredients in fossil fuels to ethene that later can
polymerize to polyethylene. Fossil fuels, being a
nonrenewable resource means that plastic is not sustainable.
Due to the extensive use of the polymer in modern society,
it’s depletion will be detrimental. However, there is a
solution; rooted in organic theory is a chemical reaction that
allows ethanol, pictured in Figure 2, to undergo a dehydration
reaction to turn into ethene:
Keywords—Biopolymer, Bio-polyethylene, Ethanol
Dehydration, Green Polyethylene, Renewable Polyethylene,
Sugarcane Ethanol, Synthesis of Ethylene
A BRIEF HISTORY OF POLYETHYLENE
Polyethylene comes from a class of compounds called
polymers. Polymers are repeated chains of molecules that can
strand from anywhere between 20 and hundreds of thousands
of atoms. There are a number of important polymers that have
modernized the world but in general the most basic one is
polyethylene. Polyethylene is very simple in structure and is
pictured in Figure 1:
FIGURE 2
Catalytic Dehydration of Ethanol to Ethene
Created Using ChemDraw
FIGURE 1
Structure of Polyethylene
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Nicholas Waters
Nicolas Valvo
Ethane
Created Using ChemDraw
The most important thing here is that although this
reaction follows a different pathway, in the end it still makes
ethene. This ethene will polymerize to polyethylene in the
same way ethene from fossil fuels does. Ethanol is a known
derivative of plant biomass which means that in many ways it
is far more sustainable as it comes from a renewable source.
It can be formed from plants through fermentation and
distillation. Several plants can be used to form it in high yields
including: sugarcane, corn, and wheat [2]. Moving forward,
every part of the sugarcane polyethylene process will be
addressed for its sustainability content. Sustainability, for the
purposes of this discussion, will deal mainly with
understanding the environmental impact that this method of
production has on the world. However, the important aspect,
will be comparing its sustainability to that of the fossil-based
process. As will be discussed later, there are issues with
wastewater and organic pollutants in the reactions that take
place to convert ethanol to polyethylene. However, it is not
about finding a new process that is completely harmless,
rather investigating a new way that is more sustainable than
the older one. Therefore, the goal of this paper is to
understand and make recommendations as to how ethanol
polyethylene, or Green-PE, production is far more
environmentally friendly and sustainable than fossil fuel
polyethylene production.
According to a case study by Thomas Race, a chemical
engineering professor at University of Texas, the generally
accepted mechanism for ethane cracking to ethene occurs at
above 650 oC [3]. If the reaction is carried out below this
temperature, many unwanted side products become more
influential and form over ethene. Because of the high
reactivity of the ethane radical, it is not totally known why the
best reaction control occurs with these conditions. The
general mechanism for ethane cracking to ethene is explained
below:
FIGURE 4 [3]
Step 1: Initiation
Created Using ChemDraw
In step 1, the ethane is placed in the high temperature
environment and the reaction conditions become great enough
that the two electrons that make up the carbon-carbon bond
split and one goes to each carbon. Note the two one sided
arrowhead which represents the flow of each electron. The
product is so reactive because electrons preferred to be paired
in any given environment. This process is a rate determining
step because it requires a high amount of activation energy
and once this occurs it starts a chain reaction that continues
until the source of ethane runs out. For the final two steps, the
structures are simplified for convenience.
THE CHEMISTRY OF POLYETHYLENE
Ethene Obtained via Ethane Cracking
The petroleum industry’s way of producing ethene, and
later polyethylene, is by using a process known as pyrolysis
or cracking. Fossil fuels contain alkanes that are formed
naturally by the breakdown of organic matter from millions
of years ago. In the right conditions, alkanes can rapidly
breakdown and convert into other smaller alkanes. At very
high temperatures the carbon-carbon bonds in alkanes
naturally start to rupture and rapidly become radicals.
Radicals are very reactive intermediates and with the right
conditions can be controlled well. When creating ethene, one
way this is done is by cracking ethane obtained from natural
gas. Ethane is pictured below:
FIGURE 5 [3]
Step 2: Propagation
Created Using ChemDraw
In the final steps, the radical interacts with another
molecule of ethane where it abducts a hydrogen and becomes
CH4, or methane. The second ethane becomes a radical which
then can spontaneously lose another hydrogen to form a more
stable double bond in C2H4, better known as ethene. The
additional hydrogen it lost moves away and is free to carry out
further reactions on ethane molecules to form more ethene or
FIGURE 3
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other side products. This reaction can be made more favorable
with catalysts but it is important to remember that it involves
destroying carbon-carbon bonds by pure force which requires
tons of energy. Therefore, the cost of production and
environmental effects are high.
Mechanism of Dehydration of Ethanol to Ethene
Ethanol can be converted to ethene through a process
called acid catalyzed dehydration which means that an acid is
used to help ethanol become ethene but then is regenerated at
the final step for further reactions. The thermodynamics of
this reaction at room temperature are not favored which is
why ethanol does not spontaneously turn into ethene on a
normal basis. The overall reaction enthalpy is positive; the
energy input needed to break bonds in the reactant (ethanol)
is larger than the energy that is given off when the bonds of
ethene are formed. However, the change in entropy of this
reaction is positive; this means that there are more products in
number that are formed than reactants that are put in. For these
two reasons, the reaction becomes favorable at very high
temperatures because of the equation for Gibbs Free Energy
which predicts whether or not a reaction is favorable at given
temperatures:
FIGURE 7
Acid catalyzed dehydration of ethanol to ethene
Created Using ChemDraw
In step 1, ethanol is placed within a reaction chamber
with an inert acidic source, such as phosphoric or sulfuric
acid, that gives off an acidic hydrogen ion. Arrow A
represents one of the lone pairs of electrons on oxygen
attracting to and forming a bond with the hydrogen ion. In
step 2, the newly formed bond creates a positive formal
charge on oxygen which destabilizes the bond of oxygen to
carbon. Arrow B represents the flow of electrons that make
up the carbon-oxygen bond moving toward oxygen to
alleviate the positive charge and destruct the bond. As the
bond is destroyed, the oxygen and two hydrogen leave
together in the form of water. In step 3, there is now a positive
charge on the carbon due to the fact that it is now missing the
former oxygen bond. It is important to note here that this is
the most unstable, high energy part of the reaction. The
molecule will do just about anything now to alleviate this
positive charge on the carbon. Many side reactions can and do
occur at this point, but they can be controlled. For the
purposes of this discussion, it will be assumed that this
reaction continues exclusively on the pathway it is supposed
to. A molecule of water can now use its lone pairs of electrons
on oxygen to attract a hydrogen from the adjacent carbon
atom (arrow C represents this process). As the hydrogen atom
is picked up, its electrons that formed the carbon-hydrogen
bond can move toward the positive charge on the adjacent
carbon atom represented by Arrow D. These two steps occur
almost simultaneously and it leads to step 4 where the ethene
is formed. In addition to ethene being formed, a molecule of
water is there from earlier when it formed in step 2. Also, the
acidic hydrogen is reformed, making it a catalyst because it
∆𝐺 = ∆𝐻 − 𝑇∆𝑆
FIGURE 6 [4]
Gibbs Free Energy
Referring to Figure 6, ∆𝐻 represents enthalpy and ∆𝑆
represents entropy. As temperature is raised, the second term
becomes more influential to the overall energy. As long as ∆𝐺
is negative, the reaction is favorable and ethene will be
formed. In a large-scale manufacturing plant, this temperature
can be as high as 500 degrees Celsius for efficient conversions
[4].
The figure below is the mechanism that allows ethanol
to become ethene, which is further used to create
polyethylene, broken down into the four steps below. In
addition, each arrow is labeled with a letter and will be
described further for why this process occurs.
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appears on both the reactants and products side of the
reaction.
The cracking of natural gas with pyrolysis is a largely
energy intensive process and because of this, contributes large
amounts of carbon dioxide to the atmosphere. Not to mention,
the non-renewability of fossil feedstocks itself is a problem.
As seen above, polyethylene can be obtained through the
pathway involved with ethanol. In addition, it is in many ways
a safer and more environmentally friendly way to produce
polyethylene because it does not involve generating the same
amounts of carbon dioxide nor heating something to
extremely high temperatures. Ethanol can be obtained from a
number of different biological sources through fermentation
and distillation of the sugars in them. The most viable are
those that produce large amounts of starches such as corn,
sugarcane, potatoes, and wheat.
Brief Discussion of Catalytic Improvement of Ethanol
Dehydration
As discussed above, ethanol dehydration can be very
unfavorable and as a result, it can be very expensive to run
this reaction. However, there are several ways to improve this
using catalysts that create more favorable reaction
intermediates. The Russian Academy of Sciences recently
published a paper discussing a number of different catalysts
and their effects on yield and efficiency on sugarcane
bioethanol. Originally, ethanol dehydration was carried out
using phosphoric acid, however according to this paper, it was
found that “Ethylene obtained with this catalyst was very
pure, but the catalyst was undergoing rapid coking” [4].
Coking meaning that the conditions of the reaction vessel
degrade the catalyst beyond further use. The paper also
looked at the use of other kinds of acids called Heteropoly
Acids (HPA’s), but they were found to be too expensive and
inefficient at high temperatures [4]. The paper later discussed
the use of metal oxides as catalysts which work by taking
advantage of the electron donating nature of transition metals.
The study found that Aluminum-Titanium Oxide are the most
active and yield a high ethanol conversion of 99.96% with
ethylene selectivity of 99.4% [4]. So, while this reaction by
itself is not very favorable, many different methods can be
used for improvement and should be investigated to make any
process of polyethylene creation more feasible and
sustainable.
Investigating the Properties of Different Sources of
Ethanol
The same Russian Academy of Sciences paper from
earlier analyzed the overall yield of ethanol based on using
one hectare of each plant, corn, sugarcane, potatoes, and
wheat. A partial amount of their data is picture in Table 1
below:
FIGURE 8 [4]
Ethanol yields of different plant based sources
Ethene Conversion to Polyethylene
Once ethene is formed, it is converted to polyethylene
via polymerization pathways. The mechanism and reaction
complex that allows ethene to polymerize is extremely
complicated involving a number of transformations and
reaction complexes. Therefore, it will not be discussed here
for it is not the main topic of this paper. In a nutshell, several
different high value metal catalysts can be used to latch onto
ethene and destabilize the double bond which can then start a
chain reaction with other ethene molecules where carboncarbon single bonds are continually formed until a long strain
of them exists as one big molecule ranging anywhere from a
thousand to a million carbon atoms.
The most important numbers are found in columns 4 and
5. They address how much ethanol is yielded, in kilograms,
based on one ton of each plant and one farmed hectare. As
seen above, the most viable of the four are sugarcane and
corn. According to the paper, “Due to high cropping capacity
and sugars/starch content and the abundance of sugarcane in
Brazil and corn in the United States, these countries account
for the greater part of the global production of ethanol from
biological raw materials” [4]. However, in this case it can be
narrowed down even further. Sugarcane ethanol wins out for
a number of reason. To start, according to an economics study
done by students at Wesleyan University, there is the issue of
cost. Ethanol can only be fermented from sugar not starch.
Corn must be converted from starch to sugar first. This step
need not be taken for sugarcane [5]. In addition, there is an
energy issue when it comes to producing ethanol with corn
versus sugarcane. According to a case study done by members
THE EFFECTS OF CHANGING THE
SOURCE OF POLYETHYLENE
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Nicolas Valvo
of the Carnegie Mellon department of Civil and
Environmental engineering published in an ACS journal,
“Production of ethanol from sugar cane can be entirely
powered by the combustion of bagasse” [6]. Bagasse is what
is left over from sugarcane after the ethanol fermentation and
distillation process has occurred. So in a sense, the production
of sugarcane ethanol creates a closed loop energy system in
which outside sources of fuel are not needed. It is a selffueling process which makes it far more sustainable than any
other form of plant ethanol. The only outside source of fossil
fuel power comes in the form of transportation trucks and
harvesting machines.
As it turns out, BraskemTM a Brazilian based company
that is currently one of the world leaders in bioethanol
production, has their own line of polyethylene called “Im
Green Polyethylene” which produces sugarcane-based
polyethylene annually at 200,000 tons per year. According to
their website, “The transformations of the green ethylene
into…Polyethylene is performed in the same polymerization
plants that produce polyethylene from fossil source” [7]. The
company is invested in making green polyethylene from
sugarcane a total alternative to the petroleum based
counterpart.
using a simple distillation column. In addition, any remaining
ethanol impurities in the ethylene compound formed can
easily be separated [8]. In conclusion, the result of the case
study deemed that “GHG[Green House Gases] in the life
cycle of bio-PE are decreased as compared to those in the life
cycle of fossil-PE.” [8]. This case study solely investigated
the greenhouse gas emissions over a lifetime of each type of
Polyethylene and found that Green-PE was far superior to
Petro-PE. Green-PE can potentially help decrease the amount
of global warming created compared to that contributed by
the Petrochemical industry.
One limitation of Green-PE is the cost of growing
sugarcane compared to drilling or extracting natural gas. For
Green-PE the sugarcane first must be grown whereas for
Petro-PE, fossil fuels are a naturally occurring source. A cost
analysis of production of ethylene done by the International
Renewable Energy Agency found that Green-PE ethylene
product costs can range from $980-$1250 per ton, whereas for
Petro-PE ethylene production ranges from $600-$1300 per
ton [9]. While these number are relatively close, it is
important to remember the Petro-PE pathway has been used
for much longer and most companies in the business have
already invested in the machinery needed for producing
ethylene via cracking. This significantly brings down costs if
you consider the price that comes with investing in the
machinery needed to extract/distill ethanol and later process
it to ethylene.
A paper by scientists at the Institute of Electrotechnics
and Energy at University of São Paulo, Brazil discusses the
sustainability content of ethanol production from sugarcane.
It focuses on farming aspects and production processes. The
paper will be used more later in the context of farming,
however, one thing they discussed in the production process
was the increase of pollutants. They found that total water
consumption was around 21 m3/ton of sugarcane [10]. They
argue that some of this water can end up polluted with organic
waste because it is used to wash the cane material with other
chemicals. This is an issue when it comes to sustainability,
because eventually this water must be disposed of. However,
the authors also say that the water used can be continually
recycled for a long time. Therefore, they recommend a system
be put in place that set rules and monitors when it can be put
back into the environment [10]. While there are some
concerns, there are solutions. When compared to the effects
that drilling can have, there is much less harm done to the
environment overall.
Green-PE has a long way to come before it can become
a total replacement. Currently, BraskemTM is the largest
producer of the product, but even at its current level, it
represents barely a fraction of the 60 million tons of plastic
consumed each year. The use of polyethylene will only grow
in the coming years, and eventually society will have to face
Comparing Polyethylene from Sugarcane and Fossilbased Feedstocks
When comparing each type of polyethylene, it is
important to note that despite each one being from different
sources, at the chemical level it is the exact same thing. There
is no comparison based on properties of the actual plastic
made each way. Instead, aspects such as environmental
performance and lifecycle assessment will be addressed to
understand where bio-PE beats out Petro-PE and where it falls
short. This in itself is an achievement because the same
product has been made using an entirely different pathway
that is completely renewable and it brings society one step
closer to breaking away from the burden of nonrenewable
petrochemicals. Also, the ability of the process to be entirely
powered by bagasse adds to its sustainability content because
it requires little excess fossil fuel power.
A Case study written by a number of different scientists
at the University of Tokyo investigated the Greenhouse Gas
Emissions associated with each type of polyethylene. For the
scenario, each type of polyethylene was synthesized in Brazil,
shipped to Japan, used in containers and packages and then
incinerated. What they found was that Green-PE beats outs
Petro-PE environmentally in a number of ways. To start, after
the cracking of natural gas to obtain ethylene at extremely
high temperatures, all that energy is lost as the products are
placed in a low temperature fractional distillation column to
separate. In contrast, Green-PE ethanol is distilled easily
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the problem that fossil-feedstocks will run out. Sugarcane PE
is a very feasible alternative and its numerous environmental
benefits will only further show how important it is to the
polymer and plastic industry.
Green Polyethylene’s Safe Alternative
The market for sugarcane is expanding because of its
versatility in many fields. Unlike many crops, sugarcane can
naturally be grown year-round. This does not come without a
cost however, as sugarcane is an extremely water-intensive
crop [13]. There is only so much land that offers the enough
water to grow sugarcane all year long and with the demand
steadily increasing to be used to make green polyethylene, it
will lead to more stress on these areas. Places such as Brazil
and India that account for large portions of sugarcane
production will need to account for more sugarcane per mile
and may need to move further inland than usual [14]. If proper
irrigation is utilized, this may have little to no negative impact
on the environment but could cause trouble for the land as the
more soil used the less predictable the next season will be with
how the weather will fare.
ENVIRONMENTAL IMPACT OF GREEN
POLYETHYLENE
Polyethylene’s structure and capabilities are hard to be
questioned as a great use to make plastics, but the impact that
producing it has on the world is still under much speculation.
The actual creation of polyethylene is not hugely impactful,
but the means of getting the raw materials to do so is alarming.
The Devastating Impact of Obtaining Fossil-based
feedstocks
Oil drilling has one of the worst impacts on the
environment than any other invention of the modern age.
Fossil fuels, the main ingredient in the production of
polyethylene is extracted from the process of drilling.
Manufacturers of polyethylene look to this source because of
its cheap and easy accessibility but do not recognize the
damage it does to the world. The drilling process is one of the
most protested in the world because of the danger it introduces
to its surroundings. First, the drilling destroys the land around
it, forcing the wildlife to migrate elsewhere or face extinction
in the area. Not only in the area directly where the drill is, but
the sound can emanate miles, disrupting the natural migration
patterns of species far away. It also pollutes the environment
in other ways for the long-term. The machinery used gives off
toxic pollutants that contaminate the air around it,
endangering the health of civilians and workers in the area
around it. The process also leads to the emissions of methane
into the atmosphere [11]. According to The Wilderness
Society, a government run organization that fights dangers
against the earth, “methane, the main component in natural
gas, is up to 84 times more harmful to the atmosphere than
carbon dioxide,” [11].
Over time, the need for drilling will increase as fossil
fuels become rarer and more expensive and will only further
jeopardize the world and the species on it. Chemical engineers
should see the use of fossil fuels in polyethylene production
as breaking the American Institute of Chemical Engineers
code of ethics, as it states, “Hold paramount the safety, health
and welfare of the public and protect the environment in
performance of their professional duties,” which certainly
does not hold in the case of drilling [12]. The alternative
offered by sugarcane based polyethylene however, is
relatively clean, safe, and efficient from an environmental
stand point.
Environmental Effects from Farming Sugarcane
Perhaps the largest issue, with sugarcane, is the
sustainability of farming it. There are numerous areas of
concern when farming becomes a large-scale process. A paper
published by scientists at the University of São Paulo
Department of Soil Sciences investigated the soil physical
quality response to sugarcane growth in Brazil. They found a
number of things to address when comparing sugarcane soil
to native vegetation soil. While the actual growing of cane is
not very demanding, the operations of farming and harvesting
are what degrade the soil. The authors argue that “intensive
sugarcane management using big and heavy machines
promotes soil compaction overtime” [15]. Compaction
decreases the soils porous nature which decreases its function
and productivity overtime. In addition, they found that some
practices need be changed because they are leading to soil
erosion by rain water. They state “Soil perturbation increases
structural degradation… decreasing the soils ability to resist
erosion” [15]. They also summarize that after the tillage
operations the soil is left uncovered for weeks to months,
which greatly increases wind and water erosion potential [15].
They recommend that management systems be put in place
because many of these practices could be easily changed and
would lead to a much more sustainable farming process in
Brazil.
Another paper, which was mentioned earlier from the
Institute of Electrotechnics and Energy at São Paulo
University, discussed the sustainability of ethanol production
from sugarcane in Brazil. One thing they focused on was
farming aspects. The scientists considered more ethical issues
associated with the farming process. They argue that
environmental issues such as deforestation and extinction of
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species should be considered when expanding farm land [10].
However, one thing they do emphasize is that Brazil
environmental policy is very good at monitoring the effects of
farming as it is a big part of Brazilian economy. They
government does a lot to ensure that farmers follow
environmental regulation and are minimizing damages to soil
and landscape [10]. This is important because any country
that is trying to adopt a sugarcane industry needs to follow in
Brazil’s footsteps to assure sugarcane production maximizes
its sustainability.
reversing the effects of fossil fuel admissions. Sugarcane,
when in high yields can decrease Green House Gases as
scientists from sugarcane.org state, “Since 2003, Brazil’s use
of sugarcane ethanol has reduced that country’s emissions of
carbon dioxide by more than 350 million tons,” [16].
The Braskem Process and Other Environmental Aspects
The figure below made by Braskem, outlines the clean
processes used to make green polyethylene and how it is used
to fix the environment.
FIGURE 10 [8]
Greenhouse gas emissions of polyethylene production
from fossil fuels vs. biomass
Figure 10 depicts the greenhouse gas emissions of
different scenarios of fossil fuels compared to those of
biomass from sugarcane to complete the process of producing
polyethylene. In each of the biomass scenarios, it is clear to
see that the greenhouse gasses taken out of the atmosphere are
equal to if not more than what is outputted into the
environment. This contrasts with fossil fuels that only emit
greenhouse gasses that harm the earth and lead to global
warming.
All products made from green polyethylene are also
completely recyclable, meaning that one unit of plastic made
from green polyethylene can essentially be used to
continually make more units in the future instead of having a
one-time use. This reduces the energy input required to make
brand new plastics when there are already pre-recycled parts
that can be reused to make a new, just as high quality plastic.
FIGURE 9 [7]
The environmentally friendly process of green
polyethylene from sugarcane to recycling
Green polyethylene markets itself from the positive
environmental impact that it has. Other than the obvious
replacement of fossil fuels that has a huge positive
environmental impact on the world, the harvest of ethanol
from sugarcane has a negative carbon footprint. The process
in which sugarcane produces its ethanol to then make ethene
captures carbon dioxide from the atmosphere. Sugarcane
stores carbon from the atmosphere into carbon stocks that are
needed for reactions that keep the ethanol inside of its stocks
until it is harvested. This allows for a large amount of carbon
to be stored in a small amount of land, reducing greenhouse
gasses tremendously [16]. The more sugarcane that is planted
will increase the positive impact on the environment as more
carbon dioxide is pulled from the surrounding atmosphere,
THE FUTURE OF GREEN
POLYETHYLENE
The research for improving green polymers such as
green polyethylene has increased and will likely continue to
do so until completely renewable resources are used more
frequently than that of fossil fuels. Eventually, bio-
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Nicolas Valvo
polyethylene can completely replace that of fossil-based
polyethylene because of the exact chemical structure and
properties that it offers.
Stephen Miller, a professor at the University of Florida,
states in a publication about the future of sustainable polymers
that, “the field of sustainable polymers is growing and
evolving at unprecedented rates,” [17]. One issue with using
green polyethylene is the possibility of the degradation of its
origins from the sugarcane feedstock. Soon, however, there
will be the possibility to incorporate new chains of molecules
such as more functional groups that will increase the effect of
water degradation and eventually be completely susceptible
to it. This new technology will allow the production of green
polyethylene to become much more efficient as every piece
of sugarcane will be able to provide ethanol to the process of
making polyethylene.
The growth of sugarcane is also becoming a higher
sought after agriculture project in many countries around the
world. Braskem can only yield 200,000 tons of green
polyethylene because there is only a limited demand as few
are willing to pay the extra costs, yet as more countries branch
out to find new ways to grow and maintain sugarcane, the
more opportunity and access there is to the ethanol to make
more green polythene that is needed to successfully combat
the production of fossil-based polyethylene. With the
increased demand of sugarcane and the new technologies that
arise from in the future, the production of green polyethylene
will overcome that of fossil-based polyethylene, leading to a
brighter and healthier world.
http://www.essentialchemicalindustry.org/polymers/polyethe
ne.html
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Recommendations for the Future
One major goal of this paper was to investigate the
sustainability aspect involved with all parts of the sugarcane
to polyethylene production process. As seen, there are many
issues that should be addressed, but can be fixed. This will
lead to a largely more sustainable process. Sustainability is an
ongoing idea and as more is learned about the impacts
environmentally, more can be done to make green
polyethylene a more sustainable alternative. Currently, the
biggest barrier is cost. It will require further research to bring
down the cost of the processes. When it does, it is a very real
possibility that the use of green polyethylene will eventually
overtake its fossil-based counterpart. Today, more than ever,
we are interested in environmental preservation. As the world
moves forward toward improving sustainability green
polyethylene should be something that moves with it.
SOURCES
[1] “Polyethylene” Essential Chemical Industry. 1.2.2014.
Accessed
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Nicholas Waters
Nicolas Valvo
[10] J. Goldemberg, S. Coelho, P. Guardabassi. “The
sustainability of ethanol production from sugarcane” Energy
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4.7.2008.
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Engineers.
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Accessed
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http://www.worldwildlife.org/industries/sugarcane
[14] “Top Sugarcane Producing Countries.” World Atlas.
3.1.2017.
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[15] M. Cherubin, D. Karlen, A. Franco, C. Tormena, C. E.P
Cerri, C. Davies, C. C. Cerri. “Soil physical quality response
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[16] Babu, Ramesh. “Current progress on bio-based polymers
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future
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talking to us about the current progress of the Green
Polyethylene and the renewable Ethanol Industry.
ADDITIONAL SOURCES
J. Koninckx. Phone interview regarding green polyethylene.
Dupont Director of BioSciences. 3.28.2017.
P. Vollhardt, N. Schore. (2014). Organic Chemistry Structure
and Function. New York, NY: W. H. Freeman and Company.
(Print Book). pp. 326-336.
S. Nelson. (2016, October). Organic Chemistry Lectures.
ACKNOWLEDGEMENTS
We would like to thank our co-chair Madeline Spiegel for
helping us along with this process. We would also like to Judy
Brink for helping us learn to use the Library system to find
some great sources. This paper would not have been possible
without the use of ChemDraw a program that can draw out
chemical reactions and molecular structures which were used
extensively in this paper. Finally, we would like to recognize
Jan Koninckx, director of BioSciences at Dupont, who took
the time to read over and edit our paper. In addition, for
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Nicolas Valvo
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