Highly efficient propane dehydrogenation promoted by reverse water–gas shift reaction on Pt-Zn alloy surfaces

Abstract

CO2-assisted propane dehydrogenation has been developed in propylene production technology to deal with thermodynamic equilibrium limitations. However, the rational design of catalysts is a crucial challenge in achieving high catalytic performances. Herein, we report the successful fabrication of highly dispersed PtZn alloy on hierarchical zeolites for CO2-assisted propane dehydrogenation through the reverse water–gas shift reaction (RWGS). Compared with monometallic Pt, the synergistic effect of PtZn plays a crucial role in both direct propane dehydrogenation and RWGS, resulting in an outstanding catalytic performance with a high turnover frequency (TOF) of 1.82 × 104h−1. From the catalytic point of view, Pt-Zn alloy surfaces facilitate the equilibrium shift in propane conversion by consuming produced H2 through RWGS with weakening CO-metal surface interaction revealed by operando studies and DFT calculations. These findings illustrate the conceptual design of alloy catalysts and allow insights into the mechanistic details of CO2-assisted alkane dehydrogenation.