Elucidating the promoting advantages and fundamentals for their creation in Sn-modified commercial CrOx/Al2O3 catalyst for propane dehydrogenation

Commercial propane dehydrogenation (PDH) catalyst of CrOx/Al2O3 are generally faced with the challenge of rapid deactivation because of severe coke accumulation, which requires frequent regeneration and causes massive emission of undesired CO2. In this work, the effect of Sn promotion on the substantial improvement of catalytic durability over the CrOx/Al2O3 during the PDH was investigated. The superior role of Sn modification is mainly based on the following features and proposed by the designed ex-situ and in-situ experiments. Firstly, electronic effects from Sn addition weaken interaction between Cr and the Al2O3 support, which is beneficial for the advantageous migration of active Cr sites during the PDH reaction. Moreover, effective regulation of catalyst surface species and acidic properties avoids the subsequent side reactions to generate coke precursors. This work provides novel inspiration for the development of the commercial CrOx/Al2O3 catalyst for PDH process.