SBA-15 Supported Organic Base Catalysts for Highly Effective Isomerization of Glucose to Fructose

Mesoporous silica material SBA-15 supported N-containing organic base catalysts were successfully synthesized and their effectiveness in isomerization of glucose to fructose were explored. The basic groups anchored on the surface of SBA-15 can readily catalyze the ketose-to-aldose isomerization. A variety of characterization methods including FTIR, XRD, BET and TEM were carried out to confirm the successful synthesis of the catalytic materials. Among these catalysts, tertiary amine tethered to the surface of SBA-15 was found to be the most reactive catalyst. Using this catalyst, a glucose conversion of 41% with a fructose selectivity of 85% could be realized at the reaction temperature of 110 degrees C and 50 min, which is close to the reaction thermodynamic equilibrium. An activation energy of 30.38 KJ/mol for the glucose isomerization reaction was calculated through reaction kinetics analysis. Additional experiments regarding the stability of SBA-15-type under reaction conditions were also carried out. The present work provided technical routes using organic base tethered onto the mesoporous materials as solid catalysts for an important biomass conversion reaction.