Fast transformation of glucose and di-/polysaccharides into 5-hydroxymethylfurfural by microwave heating in an ionic liquid/catalyst system

An efficient method for converting glucose into 5-hydroxymethylfurfural (5-HMF), in the presence of CrCl₃ catalyst, is developed by using the ionic liquid 1-butyl-3-methyl imidazolium chloride as solvent. A 5-HMF yield of 71% is achieved in 30 s for 96% glucose conversion with microwave heating at 140°C. The activation energy of glucose conversion is determined to be 114.6 kJ mol^-1, with a pre-exponential factor of 3.5Ã - 10 ¹⁴ min^-1. Fructose, sucrose, cellobiose, and cellulose are studied and 5-HMF yields of 54% are obtained for cellulose conversion at 150°C during 10 min of reaction time. Recycling of the ionic liquid and CrCl₃ is demonstrated with six cycles of use.