Ultradurable Regenerative Propane Dehydrogenation Catalyst by Fluorination-Induced Confining and Positioning

In the chemical industry, an elaborated design of catalysts for propane dehydrogenation (PDH) should be capable of high propane conversion and propylene selectivity, strong resistance to sintering and coke deposition, and easy regeneration. Here, we report a unique design of fluorinated siliceous MFI zeolite-clothed PtSn for PDH, where the fluorination induces the formation of "holes" in all-silica molecular sieves and the position of ultrasmall PtSn nanoclusters as a result of high activity, selectivity, and especially remarkable resistance to sintering during PDH over 5000 h. The present catalyst displays a near-thermodynamic-limited propane conversion and 94% propylene selectivity in pure propane, respectively, under industrially relevant conditions. Impressively, the coked catalyst can be simply regenerated by H₂ treatment at the same temperature for PDH, avoiding the complicated, poisonous, and corrosive oxychlorination process in the conventional method for regeneration, which will contribute to the extensive application of the industrial PDH process. Detailed investigations demonstrate that the strong synergy between F-modified PtSn nanoclusters and MFI zeolite can promote the selective PDH to propylene and stabilize PtSn nanoclusters against sintering and coke deposition. The unique design of the catalyst and the enhanced performance will provide a feasible strategy to solve the current difficulties in the industrial PDH process.