Study on performance of PtSn@S-1& β-Mo2C tandem catalyst in CO2-oxidative propane dehydrogenation to propylene.

Bimetallic PtSn catalysts with notable activity and selectivity are widely used in propane dehydrogenation to propylene. However, at high temperature, catalysts are prone to carbon deposition, leading to a decrease in stability. CO₂-oxidative propane dehydrogenation (CO2-PDH) has become a new research hotspot due to its potential to eliminate carbon deposition and promote the forward movement of dehydrogenation reaction while converting propane. The reverse water-gas shift catalyst β-Mo₂C with propane dehydrogenation catalyst PtSn@S-1 were mixed in CO₂-PDH, aiming to develop highly active, selective and stable catalysts. The catalysts were characterized by XRD, CO₂-TPD, C₃H₆-TPD, and thermogravimetric analysis. The research results indicate that in CO₂-PDH, the stability of the powder-mixed tandem catalyst PtSn@S-1& β-Mo₂C significantly improves by adding β-Mo₂C in series to PtSn@S-1, and the catalyst remains active without deactivation during continuous operation for 1440 min, and the high stability of the catalyst is attributed to the removal of partial carbon deposition by CO₂ during the reaction process. After optimizing the reaction conditions, it is found that when n(CO₂): n(C3H8) is 1.0 and m(PtSn@S-1):m(β-Mo₂C) is 1.0: 0.4, the powder-mixed tandem catalyst PtSn@S-1& β-Mo₂C exhibites the best performance in CO₂-PDH. The propane conversion rate remains stable at above 43.0% after 500 min and propylene selectivity exceeds 99%. [ABSTRACT FROM AUTHOR]