Carbon Dioxide as Starting Material
A research group at Stanford University has succeeded in using carbon dioxide as the starting material for furandicarboxylic acid (FDCA). FDCA can be used as a substitute for terephthalic acid during polyester production. Reaction with ethylene glycol yields polyethylene furandicarboxylate (PEF), which can be used instead of the commonly employed PET for bottles in food packaging, for instance.
PEF exhibits better barrier properties than PET, extending the shelf life of the food product contained in the packaging. In addition, compared to PET the material offers greater thermal stability and can be processed at court temperatures. In the Netherlands, the biopolymer specialist Avantium already has a pilot system for production of PEF and together with BASF intends to build a reference system for FDCA production with an annual capacity of 50 000 t/a in Antwerp/Belgium.
Conventional production of FDCA is based on fructose, which is obtained from corn, among other sources. This is where the research at Stanford University comes in. The Stanford researchers intend to eliminate the need to devote large amounts of land, energy and fertilizers to grow corn for fructose by using furfural as the starting material. This is a substance that can be obtained from agricultural byproducts.
However, since FDCA synthesis from furfural and CO2 has a high energy requirement, the furfural is first converted into furan-2-carboxylic acid. Starting with a mixture of furan-2-carboxylic acid, carbonate and carbon dioxide, the researchers created a molten salt at about 200°C. After five hours, almost 90% of this mixture had been converted into the desired intermediate product FDCA. As noted by the researchers, this reaction consumes carbon dioxide, which can be obtained from combustion of fossil fuels or other industrial processes. (hs)
Stanford scientists make renewable plastic from carbon dioxide and plants , Pressemitteilung der Stanford Universität, März 2016