The crucial role of interaction between WOx and Ti–Si composite oxide for selective hydrogenolysis of glycerol to 1,3-propanediol

Abstract

Hydrogenolysis of glycerol, a by-product in the preparation of biodiesel, to synthesize 1,3-propanediol has attracted widespread attention because of its environmental and economic benefits. How to activate the secondary hydroxyl group in glycerol to suppress the formation of 1,2-propanediol is still challenging. Pt-WOx-based catalyst has been popularly studied due to high 1,3-propanediol selectivity but its stability is unsatisfactory. Here we synthesized an oxygen vacancy-rich support (HTSO) consisting of Ti–Si composite oxide to stabilize WOx species. The glycerol conversion and 1,3-propanediol selectivity of optimized 2Pt-10WOx/HTSO-1.0 catalyst achieved 40% and 46%, respectively. Moreover, the catalytic performance remained stable over 10 reaction cycles. Based on the investigation of the structure-performance relationship of catalysts, the excellent catalytic performance was attributed to the anchoring of WOx species by oxygen vacancies, thus stabilizing the chemical valence of W. The correlation between acid sites and catalyst performance was intensively investigated. This work provides an alternative approach for preparing stable Pt-WOx-based catalysts and deepens the knowledge of the correlation between acidic sites and 1,3-propanediol selectivity.