The synthesis of new coke-resistant support and its application in propane dehydrogenation to propene

BACKGROUND: ZSM-5 zeolite has been used as a common support for PtSn-based catalyst in the propane dehydrogenation reaction. But owing to its high acidy, coke accommodation and stability of the catalyst are not satisfactory. Here, in order to improve the performance, the new hierarchical-porous ZSM-5 (abbreviated henceforth as ZQ) has been synthesized. RESULTS: By the introduction of hierarchical-pores in ZQ, the pore structure was changed, the acid content was decreased, and the surface properties were promoted. These modifications to zeolite greatly improved the capacity of catalysts to accommodate coke. Moreover, the coke deposit on PtSnNa/ZQ migrated from active metal to the support. As expected, by using the catalyst PtSnNa/ZQ, the catalytic performance of propane dehydrogenation to propene and the stability of the catalyst were significantly promoted. CONCLUSIONS: The new hierarchical-porous ZSM-5 support (ZQ) exhibits enhanced capacity to accommodate coke, and PtSnNa/ZQ enabled better propane conversion and improved catalyst stability.