An aluminum-grafted SBA-15-catalyzed conversion of glucose to 5-hydroxymethylfurfural

Environmentally friendly processes for preparing catalysts and converting glucose into 5-hydroxymethylfurfural (HMF) were studied under water-based conditions. A series of aluminum-grafted SBA-15 mesoporous silica with Si/Al molar ratios of 1.5-20 was prepared by tuning aluminum precursors, solvents, and the pH values in grafting. Among them, the 3Al-S15-w-pH 8 catalyst with high acid capacity and mixed acid sites of Lewis and Brunsted acids was fabricated by adjusting the pH value of the water-soluble aluminum precursor to 8 in a water medium. Thus, it converted 87% of glucose at 160 degrees C for 5 h in the water medium with 33% HMF selectivity. Moreover, the used 3Al-S15-w-pH 8 catalyst was easily regenerated by calcination in air, which was further used for converting glucose to HMF without losing its performance. Our findings provide new ideas for environmentally friendly catalyst preparation and biomass conversion methods, which can be readily applied to catalysis and bio-refining processes.

Automated summary

The environmentally friendly processes for preparing catalysts and converting glucose into HMF under water-based conditions were studied. A series of aluminum-grafted SBA-15 mesoporous silica catalysts with high acid capacity and mixed acid sites of Lewis and Brunsted acids were fabricated. The catalyst with pH value adjusted to 8 showed good performance in converting glucose to HMF with high selectivity, and it could be easily regenerated without losing its activity.