Catalytic Conversion of Glucose to 5-Hydroxymethylfurfural by Nanoporous Carbon Microspheres Loaded with Tin Dioxide Nanoparticles

Abstract

In this study, mesoporous carbon microspheres (MCMs) with a large specific surface area (865 m²/g) and excellent pore structure were synthesized using sucrose as a carbon source and hollow mesoporous silica spheres as a template. Subsequently, highly dispersed tin dioxide nanoparticles were loaded on MCMs by an impregnation method, yielding bifunctional catalysts (xSnO₂/MCMs) with both Brønsted and Lewis acidic sites. The ratio of Lewis acid to Brønsted acid and the overall acid density on the xSnO₂/MCMs were controlled by adjusting the amount of SnO₂ loading. Under optimal conditions (170 °C, 5 h), the 20%SnO₂/MCMs exhibited excellent catalytic performance, thereby achieving a 94.9% glucose conversion and a 75.7% HMF yield in an aqNaCl-H₂O/THF biphasic solvent system. Additionally, the 20%SnO₂/MCMs exhibited exceptional stability with constant HMF yields at 65% during five consecutive cycles and a little drop in glucose conversion. This research offered a viable approach for effectively converting glucose to HMF.