Boosting propane dehydrogenation over Sn stabilizing dispersed Ptδ+ confined in Silicalite-1 at low temperature

Utilizing the confinement effect of zeolite pores to stabilize active sites has been developed for the improvement of catalytic stability and performance. Herein, a facile strategy is proposed to synthesize a Sn stabilizing dispersed Pt delta+ sites confined in zeolite pore catalyst via Ar calcination for propane dehydrogenation (PDH). 0.2Pt/0.5Sn-S-1-Ar shows excellent propylene formation rate of 10.0 mol C3H6 center dot g(Pt)(-1)center dot h(-1) and propylene selectivity higher than 99.5% at 450 degrees C, and the superior catalyst stability in 200 h on-stream. And it has the lowest apparent activation energy barrier of 18.45 KJ/mol over Pt-based catalyst for PDH to our knowledge. According to systemic characterizations, it is demonstrated that the implantation of Sn into Silicalite-1 framework before introducing Pt is essential to generate the highly dispersed Pt delta+ species confined in zeolite pore, and the Pt delta+ species confined in zeolite pore with stronger propane adsorption and propylene desorption ability is responsible for superior PDH performance.