Efficient one-pot synthesis of n-butyl levulinate from carbohydrates catalyzed by Fe2(SO4)3

Butyl levulinate (BL) is a promising new candidate as diesel fuel and fuel additive. In this study, an efficient process for a one-pot synthesis of BL from biomass-derived carbohydrates in butanol medium with the catalysis of metal sulfates was developed. The catalytic activity of a series of metal sulfates for the synthesis of BL from fructose was investigated. Among various metal sulfates, ferric sulfate Fe 2 (SO 4 ) 3 was found to be the most efficient catalyst, which gave a remarkably high BL yield of 62.8   mol% under the conditions of 463   K, 3   h, a catalyst dosage of 5.0   g/L, and fructose concentration of 25   g/L. Different carbohydrates including glucose, cellulose , inulin and sucrose were also used for one-pot synthesis of BL with the catalysis of Fe 2 (SO 4 ) 3 , showing the yields of 39.6, 30.5, 56.6 and 50.1   mol%, respectively. In addition, the recycling and reuse of Fe 2 (SO 4 ) 3 was studied by characterizing them using powder X-ray diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS). A plausible reaction pathway for the one-pot synthesis of BL from fructose was proposed. This study provides a facile and feasible way for the synthesis of BL from biomass.