Preparation of SAPO-34-Based Catalyst for Conversion of Fructose to 5-Hydroxymethylfurfural

Solid acid-catalyzed dehydration of fructose to produce 5-hydroxymethylfurfural (5-HMF) has been a hotspot in biomass conversion research in recent years. In this study, a novel SAPO-34-based catalyst was prepared by consecutive steps of titanium doping, sulfuric acid impregnation, and sulfonic acid functionalization. Characterization of the catalyst with X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), BrunauerEmmett-Teller (BET), inductively coupled plasma optical emission spectrometer (ICP-OES), and acid-base titration revealed different pore structures and more acid content compared to SAPO-34. The catalyst was applied to the preparation of 5-HMF by dehydration of fructose, and the maximum yield (74.0%) of 5-HMF was obtained by reacting in dimethyl sulfoxide (DMSO) at 170 °C for 50 min. In addition, the applicability of the catalytic system to other substrates and the stability of the catalyst after five cycles were investigated, which are valuable for further probing on the concerned aspects.