Impact of various metal promoters on the propane dehydrogenation performance of cobalt-based catalysts

Abstract

Large-scale exploitation of natural gas and shale gas has spurred the development of the propane dehydrogenation technology. While cobalt-based catalysts, known for their low cost and low toxicity, effectively activate C–H bonds, they are often deactivated because of coke formation. In this study, we prepared SBA-15 molecular sieves using a hydrothermal synthesis method and developed a series of Co-based catalysts supported on SBA-15 with various metal promoters (denoted Co-X/SBA-15, where X = Mn, Fe, Mg, Zn, or La) via an incipient wetness impregnation method. Characterization techniques and activity evaluation results revealed that the Co–O–Mg structure in the Co-Mg/SBA-15 catalyst stabilizes the primary Co2+ active site and hinders the reduction of the CoOx species. The incorporation of Mg enhances the total alkalinity of the catalyst, facilitating propane adsorption and propylene desorption, leading to superior activity and stability. Although the addition of La improved propylene selectivity, it did not significantly enhance propane conversion. Conversely, the introduction of Mn, Fe, and Zn into the catalyst inhibited the reaction.