Green Synthesis of 5‐Hydroxymethylfurfural from Chitosan Biomass Catalyzed by Benzimidazole‐Based Ionic Liquids.

Abstract: 5‐Hydroxymethylfurfural (5‐HMF) is one of the most important platform chemicals in biorefinery, which could be further converted into bio‐fuels. In this work, an effective and green route for 5‐HMF production from chitosan biomass in a dimethylsulfoxide (DMSO)/water mixed solvent using acidic ionic liquids as the catalysts is reported. Several ionic liquids were successfully synthesized and used as catalysts for the degradation of chitosan. Benzimidazolium chloride ([Hbim]Cl) exhibited the best catalytic activity. We achieved a maximum 5‐HMF yield of 34.9 mol% in 10 wt% DMSO‐water mixed solvent. Moreover, the catalyst could be easily recycled and reused at least five times without a significant loss of activity. Our investigation involved the use of recycled catalysts and crustacean waste as the starting material, which makes the process “green” and sustainable. [ABSTRACT FROM AUTHOR]