Oxidative esterification of 5-hydroxymethylfurfural to dimethyl 2,5-furandicarboxylate over Au-supported poly(ionic liquid)s

Although fossil fuels bring convenience to the production and life of people, they also cause numerous environmental problems. As a result of overexploitation, fossil fuels are gradually being depleted as a nonrenewable resource. Biomass is a green and renewable resource and has attracted people’s attention. As a platform compound derived from renewable biomass, 5-hydroxymethylfurfural (HMF) is important for in-depth research. The oxidative esterification process from HMF to dimethyl furan-2,5-dicarboxylate (FDMC) was achieved using a gold (Au) nanoparticle (NP) catalyst supported on poly(ionic liquid)s (PILs). The comprehensive characterization of the synthesized catalyst showed that the Au NPs were successfully loaded on PILs, and a strong interaction occurred between the catalyst support and the metal. In this work, 10 %Au/PILs-Cl-1 was used as the best catalyst. The conversion of HMF ( C HMF ) and the selectivity to FDMC ( S FDMC ) reached 95.08 % and 96.82 %, respectively, under the conditions of 120 °C, 1.5 MPa, 12 h, and 0.5 equiv. CH 3 ONa. In addition, cycling experiments indicated the stability and successfully recycling of 10 %Au/PILs-Cl-1 catalyst.