Rice husk-based biogenic silica-anchored Sn-Co bimetallic catalysts for cellulose hydrogenolysis: Structural regulation and mechanism study

Abstract

The production of high value-added chemicals and materials from renewable biomass is significant for the sustainable development of chemical industry. Herein, rice husk-based biogenic silica-anchored Sn-Co catalysts with adjustable activity are successfully prepared for biomass valorization. By regulating the pretreatment method and carbothermal reduction temperature of catalysts, the interaction between Co, Sn and biogenic silica can be regulated, thereby regulating the catalytic activity of the catalyst for cellulose hydrogenolysis. 50.7 % yield of acetol and 63.4 % yield of C3 products can be obtained. A series of characterizations show that the hydrothermal pretreatment in CoCl2 solution promotes the combination of Co2+ and biogenic silica, which inhibits the excessive doping of Sn4+ and promotes the formation of Co3Sn2 alloy. The Sn-O-Si and Co3Sn2 species in 3Sn-5Co@RHC are the key active sites catalyzing glucose isomerization and fructose retro-aldol condensation. The intermediates experiments show that controlling the hydrolysis rate of cellulose to avoid excessive concentration of monosaccharide intermediates in the reaction system is crucial for inhibiting side reactions and improving the yield of acetol. The use of agroforestry waste-based catalytic materials for biomass conversion in this work can provide inspiration for exploiting the intrinsic characteristics of biomass to develop high value-added materials and chemicals.