London – There has been significant progress recently in the development of fully bio-based versions of PET (polyethylene terephthalate) – the polymer material, which is most notably used for the production of soft drinks bottles.
Among recent projects, ?chemical engineers from the University of Massachusetts Amherst and the University of Delaware, claim to have developed an efficient way to produce p-xylene - a precursor to terephthalic acid feedstock for PET.
The process employs a zeolite catalyst to transform glucose into p-xylene in a three-step reaction, which is carried out within a high-temperature biomass reactor.
The team have employed a catalyst specifically designed to promote the p-xylene reaction over other less desirable reactions. This, they claim, represents a major breakthrough since other methods of producing renewable p-xylene are either expensive or inefficient due to low yields.
“We discovered that the performance of the biomass reaction was strongly affected by the nanostructure of the catalyst, which we were able to optimise and achieve a 75% yield,” said Wei Fan, assistant professor of chemical engineering at UMass Amherst.
The research team believes further modifying the process could potentially boost the yield from the reactor.
“Our discovery shows remarkable potential,” said Dion Vlachos, director of the University of Delaware’s Catalysis Center for Energy Innovation (CCEI). “This technology could significantly reduce production costs for manufacturers of plastics from renewable sources.”
In a separate project, Avantium has generated a “technical drop-in” for the terephthalic acid component from furan dicarboxylic acid (FDCA) synthesised by dehydration and oxidation from carbohydrates.
Partners in this work include Teijin, Coca Cola, Solvay, Rhodia and Danone. The PEF material has been tested on commercial blow moulding, fibre and film lines and is said to exhibit a higher gas barrier than PET.
Avantium has recently opened its pilot plant in Geleen, the Netherlands, with the capacity of producing 40 tonnes a year of PEF for application development. The company is collaborating with Danone and Coca-Cola to help transition to the mass production of PEF bottles.
In the longer term, Avantium said it would license its ‘YXY’ technology to enable large scale, world-wide production and use of its bio-sourced plastic materials.
Elsewhere, Greencol Taiwan Corp. (GTC), a JV between CMFC (China Man-made Fiber Corp.) of Taiwan, and Toyota Tshuho of Nagoya, Japan, has adopted technology to produce monomers for bio-PET, with a new plant is due to start up in 2012. The partners also claim to have established the world’s first supply chain for bio-PET.
GTC will produce and sell bio-mono ethylene glycol, based on ethanol derived from sugar cane feedstock from Brazil. This ethanol will be secured by Toyota Tsusho, which will handle all the bio-MEG from GTC and supply it to PET manufacturers. Toyota Tsusho will also off take bio-PET from the manufacturers and sell it to end users in Japan, Europe and the US.