Bottles
By
Dan Komula
Business Analyst
Virent
Madison, Wisconsin, USA
T
he interest in bio-based plastics falls into two main areas – sustainability
and economics, and there is significant overlap between these areas. Many
companies including Coca-Cola, Pepsi, Danone, WalMart, Heinz, Nike and
others, have initiated sustainability goals including recycled PET (rPET), lightweighting
and the most recent introduction of partially bio-based PET. These sustainability
goals and programs have been driven by companies’ desires to reduce
their environmental footprint and to respond to a growing consumer demand for
sustainable and renewable packaging. Non-Government Organizations, such as
the World Wildlife Fund (WWF), have also played a large part in raising concerns
over traditional petroleum based packaging materials. The sustainability of packaging
is no longer just a ‘nice to have’ or exclusively part of a company’s corporate
social responsibility, but is seen as a business necessity to attract consumers and
protect market share in certain regions.
The other main driver for interest in bio-based plastics is the need to find an
alternative to crude oil as a basic feedstock. In the long run, crude oil will increase
in price as demand continues to grow and new oil resources become ever more
expensive to locate and develop. Therefore, companies using PET packaging are
seeking alternatives that will help them to reduce costs and minimize volatility.
While switching to other materials such as glass, metal and paper composites
is an option in certain cases, PET has replaced these materials in many uses
Completing the Puzzle:
100% Plant-Derived PET
Plant-Based
Material
BioFormPX Bio-PTA 70%
Bio-PET
Resin
Bottle
Forming
Plant-Based
Material
Ethanol Bio-MEG 50%
Paraxylene is converted into
Terephthalic Acid
(Graph: Simon, KR)
O
O
OH
OH
CH3
CH3
O2
-H2
O
Figure 1. Bio-based feedstocks for both MEG and PTA allow for
the production of a 100% renewable and recyclable PET bottle.
14 bioplastics MAGAZINE [04/11] Vol. 6
Bottles
because of a variety of benefits it offers (light-weight, clarity,
resilience, etc). Users will not give up these benefits easily. In
addition to the long run cost increases that will result from
using oil, the recent volatility of crude oil prices has also
caused problems for end users of PET. Since January 2008,
PET prices have fluctuated between $1,400 (€ 985) and $2,400
(€ 1,700) per tonne with recent prices in April 2011 hitting alltime
highs (source: CMAI Chemical Market Ass. Inc.). These
price fluctuations put pressure on the end users of PET and
wreak havoc with business planning, profit margins and
supply contracts. The risk that such volatility introduces into
the PET supply chain has a real economic cost.
Meeting sustainable packaging goals requires an efficient
and economical manner for producing renewable chemicals
that are identical to existing petroleum-derived counterparts.
Molecules that can be ‘dropped-in’ to existing supply chains
and recycling infrastructure take advantage of the extensive
capital infrastructure and production know-how already
in place today. Virent’s technology allows for leveraging of
the existing infrastructure for the production of biobased
chemicals and polymers.
PET Overview
PET (Polyethylene Terephthalate) was developed in the
1940s as a synthetic fiber polymer. Demand for the polymer
grew exponentially in the 1960s and 1970s as knit fabrics
gained popularity in fashion apparel. Today, it is a major part
of the polyester family of polymers. According to CMAI, global
demand for PET will be ~54 million metric tons in 2011.
Fibers are the dominant application of PET, accounting for
62% (CMAI) of total PET demand. PET is a high performing
synthetic fiber, as the polymer keeps its shape, color and
is extremely stain resistant. The second largest use (31%,
CMAI) of total PET demand is found in PET bottle resin. This
application started commercially in the 1970s as the soft
drink industry was attempting to source a lighter-weight
Converting Multible Feedstocks to High Value Hydrocarbons
Reactive
Intermediates
Aromatic-rich
BioFormate BioParaXylene
BioBenzene
BioToluene
BioXylenes
BioFuels
Bioforming Process
Aqueous
Phase
Reforming
Virent
Modified
ZSM-5
Aromatics
Complex
Figure 2. Virent’s BioForming process utilizes the patented APR process coupled with conventional
catalytic conversion technologies and petrochemical operations to produce BioFormPX.
BiomassSugarCaneCorn
bottle to replace glass, while still maintaining the clarity and
appeal of a glass bottle. The industry found PET resin was
ideal for its needs, and the stretch blow molding process was
born. The remaining demand for PET is in films (4%) and
other small niche market applications (3%).
There are two streams of raw materials which comprise
PET: Mono-Ethylene Glycol (MEG), and Purified Terephthalic
Acid (PTA). PTA is made from paraxylene, and historically,
all of these raw materials have been sourced from fossil
resources (crude oil and natural gas).
The MEG portion of PET can be produced from traditional
petrochemical routes via ethylene or can be produced
from natural plant sources (via fermentation to ethanol
and dehydration to ethylene). The PTA/paraxylene portion,
representing approximately 70% (by wt. or even 80% if we just
look at the carbon atoms) of the PET molecule has remained
a fossil-fuel component derived from petroleum refinery
streams, due to the difficulty of producing the aromatic
paraxylene molecule from bio-based sources. That has been
the difficulty for companies seeking a 100% bio-based PET
polymer. Now Virent has demonstrated a route to make biobased
paraxylene that opens up the potential for 100% biobased
PET.
BioFormPX™ Production Enabling
a 100% Biobased PET bottle
Virent is making paraxylene as well as other chemicals
and biofuels through its patented technology. Coupled with
biobased MEG, Virent’s BioFormPX allows bottlers and
other packaging companies to offer their consumers 100%
renewable and recyclable PET bottles as well as fibers and
films.
Virent’s BioForming®
Platform
Virent’s process, trademarked BioForming®
, is based on
a novel combination of Aqueous Phase Reforming (APR)
bioplastics MAGAZINE [04/11] Vol. 6 15
technology with modified conventional catalytic processing technologies.
The APR technology was discovered at the University of Wisconsin in 2001
by Virent’s founder and Chief Technology Officer, Dr. Randy Cortright. The
BioForming platform expands the utility of the APR process by combining
APR with catalysts and reactor systems similar to those found in standard
petroleum oil refineries and petrochemical complexes. The process converts
aqueous carbohydrate solutions into a mix of hydrocarbons. The BioForming
process has been demonstrated with conventional sugars as well as a wide
variety of cellulosic biomass from non-food sources.
Virent’s aqueous phase reforming methods utilize heterogeneous catalysts at
moderate temperatures (450 to 575 K) and pressure (10 to 90 bar) in a number
of series and parallel reactions to reduce the oxygen content of the feedstock.
The reactions include: (1) reforming to generate hydrogen, (2) dehydrogenation
of alcohols/hydrogenation of carbonyls; (3) deoxygenation reactions; (4)
hydrogenolysis; and (5) cyclization. Once formed, Virent has found that these
mono-oxygenated species (e.g. alcohols, ketones and aldehydes) can be
converted to non-oxygenated hydrocarbons in a continuous process using
conventional catalytic condensation and hydrotreating techniques.
The production of Virent’s bio-paraxylene, branded BioFormPX involves
the APR process followed by a modified acid condensation catalyst (ZSM-5)
which produces a stream similar to a petroleum derived reformate, branded
BioFormate™. In the acid condensation step, the APR products are converted
into a mixture of hydrocarbons, including paraffins, aromatics and olefins.
The similarity between Virent’s BioFormate stream and a typical petroleum
reformate stream is shown in Fig 4.
The resultant BioFormate stream has been blended into the gasoline pool
and can be subsequently processed into high value chemical intermediates,
such as paraxylene using commercially proven and practiced technologies.
Virent’s BioFormate stream has been blended by Royal Dutch Shell into a
gasoline fuel used by the Scuderia Ferrari Formula 1 racing team.
Virent has produced sufficient quantities of its BioFormate through
operation of its 37,800 Liter (10,000 gallon) per year demonstration plant to
generate volumes for further processing to paraxylene. Virent completed in
house purification through the use of commercial crystallization techniques to
produce a purified bio-paraxylene product. The use of crystallization technology
is used to meet the industry required specification of 99.7+% purity.
Virent Energy Systems, Inc.
Virent was founded in 2002 and is
headquartered in Madison, WI, USA.
The company produces the chemicals
and fuels the world demands from a
wide range of naturally occurring,
renewable resources. Using patented
catalytic chemistry, Virent converts
soluble biomass-derived sugars
into products molecularly-identical
to those made with petroleum,
including gasoline, diesel, jet fuel,
and chemicals used for plastics and
fibers. Virent’s technology has the
potential to replace over 90% of the
products derived from a barrel of
crude oil.
Figure 3. Virent uses catalysts to reduce the oxygen content of the feedstock. Once formed, the mono-oxygenated species are converted
to non-oxygenated hydrocarbons in a continuous process using conventional catalytic condensation and hydrotreating techniques.
R
O O OH
OH OH
OH
OH
OH OH
OH R
OR
OH
OH
OHOH
HO
HO
HO O
O
O
O
O
OH
OHOH
OH
HO
O
O
O
O
R
OH
O
OH OH
O
OH OH
OH
O
O
OH
HMF
Xylose
Glucose
Levulinic Acid
Benzoic AcidCellulose Oligomers
Xylose Oligomers
APR ProductsAPR Reactant
R
R
O
O
O
OH
HOHO
OH
OH
OH
OH
O
O
R
O
OH
R
R
Bottles
16 bioplastics MAGAZINE [04/11] Vol. 6
Road to Commercialization
Virent is currently in discussions with a number of major end users of
PET fiber, bottle resin and film, to commercialize the BioForming platform
for the production of BioFormPX. Manufacturers involved in the traditional
petrochemical PET supply chain have also expressed interest in contributing
to building out the biobased PET supply chain. The ability of Virent to use
existing petrochemical assets and technologies accelerates the time to
commercial deployment. Virent is targeting commercial production of its
BioFormPX by 2015 or earlier and believes that the demand pull from the
major end users of PET is crucial to the initial commercialization and success
of bio-based PET.
Virent’s BioForming platform for BioFormPX produces other bio-based
aromatic intermediates, including benzene, toluene and other xylenes,
as well as biofuels. These other aromatic intermediates can be used to
produce biobased polystyrene, polycarbonate, and polyurethane. This
diversified product slate allows for de-risking of commercial deployments
as the profitability is not dependent on one molecule or market. Virent has
produced material that would be suitable using today’s aromatics processing
infrastructure from its 37,800 Liter per year demonstration plant. While that
is sufficient volume to provide samples to prospective partners, the current
demand for plant-based paraxylene is even more significant and is poised
to grow at high rates in the future. Virent envisions the BioForming platform
as being an industry wide solution enabling 100% bio-based PET while
complementing petroleum based PET.
The ability of Virent to use existing petrochemical assets and technologies
accelerates the time to commercial deployment. The scale of this plant is yet
to be finalized and will depend on a number of factors including feedstock
source, logistics, and customer demand. Potential plant sizes range from
30,000 tonnes/yr to 225,000 tonnes/yr of BioFormPX production. The large
scale plant could produce 30 Billion 0.295 Liter (10 oz) bio PET water bottles
or 17 Billion 0.590 Liter (20 oz) bio PET soft drink bottles. The introduction
of this first plant can have a large impact on the PET bottle industry and the
implementation of future plants will increase the impact.
	www.virent.com
Figure 5. Virent’s 10,000 gallon/yr
BioFormate demonstration plant (top)
and Virent’s BioFormPX (bottom) in
its crystalline form during in house
purification.
Virent’s BioFormate
Petroleum Reformate Stream
Figure 4: Virent’s plant-based reformate bears striking resemblance to that
found at a typical refinery
Petroleum Reformate Stream
Virent’s BioFormate
Bottles
bioplastics MAGAZINE [04/11] Vol. 6 17