Oxygen Vacancy Engineering on Pt/WO<sub><i>x</i></sub>/Nb<sub>2</sub>O<sub>5</sub> Catalysts toward Efficient 1,3-Propanediol Production from Glycerol Hydrogenolysis
Malin Eqi, Yuqing Yang, Guangjun Wu, Landong Li, Yuchao Chai
Abstract
The hydrogenolysis of biomass-derived glycerol to 1,3-propanediol is an important process in biomass valorization, while the selective cleavage of the secondary hydroxyl group (C 2 –OH) in glycerol remains a key challenge in chemistry and catalysis. We report herein a multistep approach for the construction of Pt/WO x /Nb 2 O 5 featuring abundant oxygen vacancies and strong Pt δ+ –O–W interactions thereof, making Pt/WOx/Nb 2 O 5 a robust catalyst for glycerol hydrogenolysis to 1,3-propanediol. Typically, the optimized Pt/WO x /Nb 2 O 5 catalyst achieves remarkable performance in the hydrogenolysis of a high-concentration glycerol solution (50.0 wt %) with a glycerol conversion of 94.9%, a 1,3-propanediol selectivity of 67.3%, and a glycerol space-time yield of 0.490 g g cat –1 h –1, surpassing all known catalyst systems. The presence of abundant oxygen vacancies in Pt/WO x /Nb 2 O 5 is directly visualized by microscopy, and the essential role of Pt δ+ –O–W interactions in the reaction is well interpreted by spectroscopic analysis. The Pt δ+ –O–W interactions can promote the selective adsorption of the secondary hydroxyl group in glycerol and the hydrogen spillover from Pt to WO x for in situ Brønsted acid site generation, both facilitating the selective hydrogenolysis of glycerol to 1,3-propanediol. Overall, we show here a successful example of catalyst design via oxygen vacancy engineering for an important process, biomass valorization.