(535g) Production of Biorenewable Monomers - from Fructose to 2,5-Furandicarboxylic Acid

The demand for bio-based polymers is increasing globally due to their lower carbon footprint and independence from fossil fuels. 2,5-Furandicarboxylic acid (FDCA) is a potential bio-based alternative to terephthalic acid for the production of bio-based polymer polyethylene furanoate (PEF). However, the economical production of FDCA from carbohydrates must address technological challenges, such as instability of hydroxymethylfurfural (HMF), low solubility of FDCA, and requirement of stoichiometric amounts of base for the oxidation of HMF to FDCA.

We will report a process for production of FDCA from fructose which utilizes a solvent system comprising of a polar aprotic solvent and water to address the aforementioned challenges. We will discuss the role of solvent in stabilizing HMF, thereby leading to high yield. In our process, a high concentration of fructose (15 wt%) is dehydrated to HMF, and HMF is then oxidized to FDCA over a heterogeneous catalyst (Pt/C) without intermediate separation. We demonstrate that the γ-Valerolactone (GVL)/H₂O solvent system has high FDCA solubility which not only leads to high FDCA yield but also eliminates the need of a homogeneous base during HMF oxidation. We further show that FDCA can be separated from the GVL/H₂O solvent system by crystallization, and a highly pure (>99% purity) FDCA product is obtained. Furthermore, we demonstrate that FDCA is an effective catalyst for fructose dehydration in GVL/H₂O, which obviates the need of a mineral acid catalyst, thereby improving both the economic and the environmental impact of the process. Our techno-economic model indicates that the overall process is economically competitive with current terephthalic acid processes.