Dehydration of fructose into 5-hydroxymethylfurfural in acidic ionic liquids

A simple and effective process for the dehydration of fructose into 5-hydroxymethylfurfural (HMF) using ionic liquid 1-(4-sulfonic acid) butyl-3-methylimidazolium hydrogen sulfate (IL-1) as the catalyst was developed. High fructose conversion of 100% with HMF yield of 94.6% was obtained at 120 degrees C for 180 min reaction time in water-4-methyl-2-pentanone (MIBK) biphase system. Generally, the increase of water content had a negative effect on the reaction, the HMF selectivity decreased as the excessive elevation of temperature and prolonging of time, which suggested the decomposition of HMF. The ionic liquid IL-1 could be recycled and exhibited constant activity for six successful runs. This paper provided a new strategy for HMF production from fructose.