Plastics are often derived from petroleum, contributing to reliance on fossil fuels, and driving harmful greenhouse gas emissions.
Using a plant-derived solvent called GVL (gamma-Valerolactone), an economical and high-yielding way to produce furandicarboxylic acid (FDCA) was developed. One of 12 chemicals the U.S. Department of Energy calls critical to forging a “green” chemical industry, FDCA is a necessary precursor to a renewable plastic called PEF (or polyethylene furanoate), as well as to a number of polyesters and polyurethanes.
As the bio-based substitute for PET (polyethylene terephthalate) — its widely used, petroleum-derived counterpart — PEF is rich in potential. PET currently has a market demand of close to 1.5 billion tons per year, and a number of large companies have committed to developing a sustainably sourced, 100% plant-based PET for their bottles, packaging, apparel, and footwear. PEF's potential to break into that sizeable market, however, has been hampered by the high cost of producing FDCA. FDCA has had very low solubility in practically any solvent — a significant amount of solvent is necessary to make a small amount of FDCA, resulting in high separation costs and undesirable waste products.
The new process begins with fructose, which is converted in a two-step process to FDCA in a solvent system composed of one part GVL and one part water. Since sugars and FDCA are both highly soluble in this solvent, the end result is a high yield of FDCA that easily separates from the solvent as a white powder upon cooling. The solvent then can be easily separated and recycled.
The system doesn't require costly mineral acids for catalysis, doesn't produce waste salts, and the FDCA crystals can be separated from the solvent by simply cooling the reaction system.