Attractive performance Cr-Co/ZSM-5 catalysts for the oxidative dehydrogenation of propane with carbon dioxide

Oxidative dehydrogenation of propane (ODHP) with CO2 offers a viable alternative to enhance the utilization of CO2 to produce high-value-added propene. However, the propene yield is still low to meet industrial applications. Therefore, in this study, we synthesized bimetallic CrCo oxides over ZSM-5 support using wet impregnation and sol-gel methods for the Time on stream ODHP with CO2 at 550 degrees C and 600 degrees C. The catalysts synthesized via the wet impregnation method exhibited high specific surface area, allowing for better dispersion of the CrOx and CoOx on the ZSM-5 surface, thus giving an attractive catalytic performance. The 5Cr-Co/ZSM-5 (w) catalyst demonstrated the highest propane conversion (53.90 %), propene selectivity (71.65 %), and yield of propene (38.62 %). This performance is attributed to the synergistic effects arising from the effect of the Br & Oslash;nsted/Lewis acid sites ratio from the ZSM-5 framework as well as those generated from chromium and cobalt metal species. The formation of highly dispersed Cr6 + and Co3+ species exchanged with the acidic protons of the zeolite framework contributes to the strong Lewis acidity. In particular, the Lewis acid site plays a crucial role in adsorbing CO2 and facilitating the activation of the C-H bonds. In contrast, Br & Oslash;nsted acid sites enhance the adsorption of propane molecules onto the catalyst surface. These findings are important for developing highperformance bimetallic CrCo-based catalysts for CO2-ODHP.