Framework Zr Stabilized PtSn/Zr-MCM-41 as a Promising Catalyst for Non-oxidative Ethane Dehydrogenation

Comprehensive Summary Non-oxidative ethane dehydrogenation is a promising route to produce ethene. Herein, PtSn supported catalysts were investigated to achieve better ethane dehydrogenation performance by introduction of different Zr promoters, i.e. , framework Zr and ZrO 2 , to mesoporous MCM-41. In-situ XRD, TEM and CO chemisorption show that aggregation of metal particles and phase segregation of Pt 3 Sn to Pt and PtSn 3 at high temperature occur for PtSn/M, leading to bad ethane dehydrogenation activity. Strong interaction between ZrO 2 and PtSn species, as proved by XPS, results in restrained metal particles, which promotes the initial reactivity. However, Pt phase generated on surface is disadvantageous for the desorption of produced ethene as indicated by CO-IR and C 3 H 6 -TPD, and pyridine-IR and NH 3 -TPD indicate strong acidity generated. Both deactivate the catalyst rapidly by deep dehydrogenation and coking. Moderate interaction between PtSn species and Si-O-Zr with much weaker acidity is formed when framework Zr is incorporated into MCM-41, which benefits the dispersion of metal particles, formation of Pt 3 Sn/Pt species and stabilization of metal species from phase segregation. Outstanding initial ethane conversion and ethene selectivity of ca. 99% were achieved for the optimal PtSn/ZrM, which is more coking-tolerant and stable by generating graphitic carbon mainly on support instead of active metals.