Mesoporous Ti-W oxide: synthesis, characterization, and performance in selective hydrogenolysis of glycerol

摘要

Mesoporous Ti-W oxides, bearing high surface area, large pore volume, uniform pore size and tunable W/Ti ratios in a wide range (10-40 mol%), were successfully fabricated via an evaporation-induced self-assembly (EISA) strategy. In this approach, the incorporation of W species not only effectively resulted in well-ordered mesoporous structures when calcined below 400 °C but also modified the acidic properties of the obtained oxide composites. The optimal acid amounts (0.47-0.67 mmol g~(-1) for 400 °C calcinations, 0.25-0.27 mmol g~(-1) for 500 °C calcinations) were obtained when the W concentration was between 10 and 20 mol%. When calcined at 500 °C, Bronsted acids were generated in Ti_(90)W_(10)-500 and Ti_(80)W_(20)-500. The catalytic performance of these mesoporous solid acids in glycerol hydrogenolysis was studied with a loading of 2 wt% Pt. Pt/Ti_(100-n)W_n-500s exhibited high selectivity to 1,3-propanediol (33.5% and 40.3%) and promising catalytic activities (18.4% and 24.2% glycerol conversion) when n is 10 and 20, respectively. This work presents a step forward in the development of highly efficient glycerol hydrogenolysis catalysts and a new understanding of the reaction mechanism of glycerol hydrogenolysis to 1,3-propanediol.