Dehydration of glucose into 5-hydroxymethylfurfural in SO3H-functionalized ionic liquids

The continuous dehydration of D-glucose into 5-hydroxymethylfurfural (HMF) was carried out under mild conditions, using SO3H-functionalized acidic ionic liquids as catalysts and H2O-4-methyl-2-pentanone (MIBK) biphasic system as solvent. High glucose conversion of 97.4% with HMF yield of 75.1% was obtained at 120 degrees C for 360 min, also, small amounts of levulinic acid (LA) and formic acid were generated. Generally, the dosage of catalyst and the initial content of glucose influenced the reaction significantly; the HMF selectivity decreased with the excessive elevation of temperature and prolonging of time; and water content in the system had a negative effect on the reaction. The ionic liquid catalyst could be recycled and exhibited constant activity for five successful runs. This paper provided a new strategy for HMF production from glucose. (C) 2014 Fu-Rong Tao. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.