Facile synthesis of hierarchical porous catalysts for enhanced conversion of fructose to 5-hydroxymethylfurfural

Facile synthesis of solid acid carbonaceous catalysts with hierarchical pore structure has been reported. As carbonaceous catalyst precursor, MOF-derived carbon (MDC) was prepared by a simple heat-treatment of highly crystalline metal-organic framework-5 (MOF-5) without any complicated process and environmental burden. Subsequently, −SO₃H groups with high catalytic activity were successfully grafted onto the carbonaceous support by the sulfonation process. The obtained catalysts, MDC-SO₃H have been systematically studied as acidic heterogeneous catalyst in dehydration of fructose into 5-hydroxymethylfurfural (5-HMF) with isopropanol-mediated DMSO solvent. The experiment results proved that the efficient 5-HMF yield was gained in mixed solvent which a large amount of DMSO was substituted by isopropanol. The highest yield of 5-HMF (89.57%) was obtained at 120 °C for 2 h with the use of 90 vol. % isopropanol as the cosolvent in our experiment. What's more, the catalyst showed excellent recyclability after 5 times catalyze reaction without significant loss of catalytic activity.