Fabrication of the Core-Shell Structured ZSM-5@Mg(Al)O and Its Catalytic Application in Propane Dehydrogenation

In this study, a novel core-shell structure of ZSM-5@Mg(Al)O (abbreviated as Z@MA) was designed by using the sol-gel method, and the influence of different weight ratios of Mg(Al)O/ZSM-5 on the structure and catalytic performance was investigated. The as-obtained materials were characterized by XRD, N-2-physisorption, SEM, FT-IR, NH3-TPD and XPS analyses. The results showed that, with the increase of the weight ratio of Mg(Al)O/ZSM-5, the thickness of Mg(Al) O shell was improved, and the pore structure and physiochemical properties of core-shell materials were directly modified. After introduction of Mg(Al) O, the acidity properties of different materials were significantly suppressed. Meanwhile, more Sn oxide species in Z@MA could facilitate the anchoring of Pt on the support. By effectively employing these modifications, the capacity of the catalysts to accommodate coke was significanty improved and the carbon deposits were migrated from active metal to the carrier. When the weight ratio was equal to 3, the catalyst PtSnNa/Z@MA showed a highest conversion and high selectivity in propane dehydrogenation.