Conversion of Eucalyptus Cellulose into 5-Hydroxymethylfurfural Using Lewis Acid Catalyst in Biphasic Solvent System

Abstract

Conversion of eucalyptus cellulose into 5-hydroxymethylfurfural (5-HMF) by using Lewis acid catalyst in biphasic system was investigated in this study. The results show that the tetrahydrofuran/water biphasic system was more conducive to convert the eucalyptus cellulose into 5-HMF comparing to the single aqueous system. InCl3, a water-compatible Lewis acid, has the best catalytic effect. The highest yield of 5-HMF from eucalyptus cellulose is up to 45.05 mol%, which is a slight higher than that from microcrystalline cellulose. It can be ascribed to the lower crystallinity of isolated eucalyptus cellulose. The optimum conditions for catalytic conversion of eucalyptus cellulose into 5-HMF are at 200 °C for 2 h with 10 % InCl3 dosage. Additionally, the effect of recycling the whole biphasic system which contains InCl3, NaCl, H2O and THF indicated that the 5-HMF yield was gradually decreased as the cycle times increased, the possible reason could be due to the loss of partial InCl3 catalyst during the separation and distillation process.