Copper-Based Catalytic Anodes To Produce 2,5-Furandicarboxylic Acid, a Biomass-Derived Alternative to Terephthalic Acid

2,5-Furandicarboxylic acid (FDCA) is a key near-market platform chemical that can potentially replace terephthalic acid in various polyesters such as polyethylene terephthalate (PET). FDCA can be obtained from oxidation of 5-hydroxymethylfurfural (HMF), which can be derived from cellulosic biomass through isomerization and dehydration of hexoses. In this study, electrochemical oxidation of HMF to FDCA is demonstrated using Cu, one of the cheapest transition metals, as the catalytic anode. The oxidized Cu surface is not catalytic for water oxidation, which is the major reaction competing with HMF oxidation in aqueous media. Therefore, a wide potential window to oxidize HMF without inducing water oxidation was available, enabling high Faradaic efficiencies for FDCA production. Cu was prepared as nanocrystalline and bulk electrodes by electrodeposition, and key differences in their surface oxidation and electrochemical HMF oxidation were investigated. The oxide and hydroxide layers formed on the nanocrystall...