Green process for the production of 5-chloromethylfurfural from concentrated cellulosic biomass feedstock in deep eutectic solvent

The compound 5-(Chloromethyl) furfural (CMF) is a novel and versatile biobased platform molecule, possessing numerous exceptional properties that position it as an outstanding alternative to 5-Hydroxymethylfurfural (HMF). In this work, we demonstrate a green and efficient route for direct production of CMF from biomass waste corncob residue with high substrate concentration in deep eutectic solvents (DESs). Ideal CMF yields of 27.51, 21.75, 17.84, and 16.01 % could be obtained from biomass substrate concentrations of 5, 10, 15, and 20 %, respectively. The DES/Methyl isobutyl ketone (MIBK) biphasic reaction system with effective cycling performance was raised to deal with various biomass feedstocks. Subsequently, we also synthesized solid acid catalysts 0.2Al/MCM-41 and applied them to the CMF preparation, which has significant advantages in cycling performance, although their catalytic performance is relatively low. Besides, further investigation of the formation process of CMF in DES is conducted through experiments and theoretical calculations.