Bottles By Dan Komula
Bottles By Dan Komula Business Analyst Virent Madison, Wisconsin, USA Completing the Puzzle: 100% Plant-Derived PET CH 3 CH 3 O 2 -H 2 O O O OH OH Paraxylene is converted into Terephthalic Acid (Graph: Simon, KR) The 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 Figure 1. Bio-based feedstocks for both MEG and PTA allow for the production of a 100% renewable and recyclable PET bottle. Plant-Based Material BioFormPX Bio-PTA 70% Plant-Based Material Ethanol Bio-MEG 50% Bio-PET Resin Bottle Forming 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 ,400 (€ 985) and ,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 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) Converting Multible Feedstocks to High Value Hydrocarbons Biomass Sugar Cane Bioforming Process Aqueous Phase Reforming Reactive Intermediates Virent Modified ZSM-5 Aromatic-rich BioFormate Aromatics Complex BioParaXylene BioBenzene BioToluene BioXylenes BioFuels Corn Figure 2. Virent’s BioForming process utilizes the patented APR process coupled with conventional catalytic conversion technologies and petrochemical operations to produce BioFormPX. bioplastics MAGAZINE [04/11] Vol. 6 15
