Preparation of 5-hydroxymethylfurfural from cellulose catalyzed by silicon-based composite solid acids.

In order to improve the efficiency of solid acid catalyzed cellulose preparation of 5-hydroxymethylfurfural (HMF), this study prepared a silica-based solid acid with dual acid sites comprising both Lewis and Brønsted acids. Firstly, SiO2 microspheres prepared by reverse microemulsion method were used as the carrier, and the surface was modified with -SO3H and -NH2, and finally Cr3+ was loaded on to SiO2 to prepare the composite solid acid catalyst Cr-SiO2-SO3H, and its characterization and catalytic performance were determined. The experimental results showed that in the two-phase reaction system composed of [BMIM]Cl and THF, using microcrystalline cellulose (MCC) as the substrate, when the reaction temperature was 160 °C, the reaction time was 4 h, the addition amount of Cr-SiO2-SO3H was 1 g/g (cellulose), and the volume ratio of [BMIM]Cl to THF was 1:3, the maximum yield of HMF could reach 54.8%, which was 1.49 and 1.34 times the maximum yield of SiO2-SO3H and Cr-SiO2, respectively.