Solid-state NMR studies of sulfonated SBA-15 and the synergistic catalysis of fructose into 5-hydroxymethylfurfural with dimethyl sulfoxide

Abstract

Sulfonic acid functionalized mesoporous SBA-15 was prepared using the grafting method. The structure and acid properties were comprehensively characterized using multi-nuclear and quantitative probe molecule solid-state NMR (SSNMR), together with powder X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), N2 adsorption-desorption techniques. Its catalytic performance in the conversion of fructose to 5-hydroxymethylfurfural (HMF) in dimethyl sulfoxide (DMSO) was studied. Catalyst dosage, reaction time, reaction temperature and solvent effect have been investigated. A high yield of HMF up to 93% was obtained at a relatively low temperature of 373 K for 180 min. The Brønsted acid of SBA-15_SO3H together with the solvent DMSO was found to synergistically catalyze the reaction. The catalyst preserved most of its activity after five times reuse and the catalytic activity can be recovered by H2O2 process.

Keywords

• Solid acid
• Solid-state NMR
• Molecular sieve
• Heterogeneous catalysis
• Biomass