Tin-Promoted Platinum Supported on CeOx nanoclusters Catalysts for CO2-Oxidative Dehydrogenation of Propane

Abstract

The oxidative dehydrogenation of propane with CO2 (CO2-ODHP) technology is recognized as a promising new route for propylene production, owing to its advantages in energy saving, high yield, and environmental friendliness. However, the inherent complexity of the reaction system and catalyst structures has led to ongoing debates regarding its activation mechanisms and reaction pathways. Thus, the development of high-performance catalysts capable of synergistic activation of propane and CO2 with simultaneous high propylene selectivity continues to be a key objective and challenge. This study aimed to investigate the catalytic activity of Pt-based catalysts supported on CeOx nanoclusters for the CO2-ODHP reaction, from the perspective of enhancing CO2 adsorption and activation. Experimental results demonstrate that the oxygen-rich defect structure on the CeOx nanoclusters significantly promotes the activation and dissociation of CO2. Furthermore, the incorporation of Sn effectively enhances the dispersion of Pt species and their surface electron density, thereby further strengthening the strong adsorption and activation of propane, while simultaneously facilitating the desorption of propylene. Following continuous operation for 5 h at 550 °C, the 0.5Pt2.0Sn/CeOx-SiO2 catalyst demonstrated superior catalytic performance, achieving a propane conversion of 45.3% and a propylene selectivity of 93.6%. Based on in-situ DRIFTS analysis, a possible reaction mechanism for CO2-ODHP on this catalyst is proposed. The findings of this study provide crucial theoretical guidance and practical references to further advance high-performance Pt-based catalysts for CO2-ODHP reactions.