High yield production of 5-hydroxymethylfurfural from cellulose by high concentration of sulfates in biphasic system

A high 5-hydroxymethylfurfural (HMF) yield of 53 mol% was obtained by direct degradation of cellulose in a biphasic system with concentrated NaHSO4 and ZnSO4 as co-catalysts, with 96% of cellulose conversion in 60 min. The high concentration of catalysts in the aqueous solution and the high volume ratio of organic phase to aqueous phase were responsible for the excellent performance. The depolymerization of cellulose is the rate-determine step, and the formed glucose could be efficiently converted by concentrated catalysts in the aqueous solution, leading to low concentration of glucose in the solution and thus suppressing the side reactions such as humin and char formation.