Promoting Role of Oxygen Deficiency on a WO3-Supported Pt Catalyst for Glycerol Hydrogenolysis to 1,3-Propanediol

Abstract

The supported Pt and WOx catalysts are widely studied for the hydrogenolysis of glycerol to 1,3-propanediol. Nevertheless, the promoting role of W species remains unclear owing to the complexity in ternary hybrid catalysts. Herein, tungsten oxides (WO3·0.33H2O) with the varying quantities of oxygen vacancy (VO) were successfully synthesized and directly used as a support for loading Pt. The platinum loading high oxygen vacancies (H-WO3) containing VO in abundance showed much higher catalytic activity and selectivity than that for low oxygen vacancies (L-WO3). The uniform dispersion of Pt particles, the high acidity, and the strong Pt and support interaction observed on Pt/H-WO3 are associated with the existence of VO in a large amount, resulting in the significant enhancement in the catalytic performance. A plausible model for glycerol hydrogenolysis on Pt/H-WO3 was proposed, wherein the unsaturated W ions coordinate with two terminal −OH groups of a glycerol molecule, and the secondary −OH group was protonated by the B acid from the Pt–(WOx)n–H as well as the in situ generated Hδ+ species.