Direct Conversion of Cellulose to Levulinic Acid over Multifunctional Sulfonated Humins in Sulfolane–Water Solution

Abstract

Levulinic acid (LA) is an ideal platform chemical that can be generated by acid-catalyzed dehydration and hydrolysis of sugars from lignocellulosic biomass. Hereby, we reported an environmental benign process for selective conversion of cellulose and bamboo meal to produce LA efficiently. When multifunctional sulfonated humins (MSH) was used as the catalyst in 90 wt % of aqueous sulfolane solution, cellulose was converted to LA with a high yield of 65.9 mol %. The MSH exhibited outstanding performance both on the catalytic activity and retrievability due to its synergistic effect with sulfolane and water. High LA yield of 45.6 mol % was also obtained from real biomass (bamboo meal), which is efficiency and specificity in parallel to liquid acid catalyzed process. Furthermore, all the solvent, catalyst, and byproducts (humins and furfural) in this process could be easily recycled and reused, which proposed a new strategy for high value-added utilization of agriculture and forestry lignocellulosic residues.