Propane Dehydrogenation Over the Catalyst with Stable and Dispersed Pt Clusters on Zn-MSN Support

Abstract

Propane dehydrogenation (PDH) over platinum-based bimetallic catalysts has received widespread attention as an on-purpose technology for producing propylene. However, catalysts prepared using the traditional impregnation method usually show a weak interaction between the support and active Pt sites. Moreover, catalysts undergo structural changes in a high-temperature-reducing atmosphere, resulting in decreased activity during the reaction. To enhance the metal–support interaction, Zn-doped mesoporous silica nanoparticle (Zn-MSN) supports were prepared using a one-step synthesis to support Pt species. The addition of Zn altered the surface properties of the MSN support, increasing the number of surface hydroxyl groups and thereby improving the dispersion of [Pt(NH₃)₄]²⁺ on the catalyst surface through electrostatic interactions. The Pt/2.0Zn-MSN catalyst, with highly stable and dispersed Pt clusters, showed the highest PDH activity, with an initial propane conversion and propylene selectivity of 51.3% and 98.7%, respectively. It also showed strong resistance to coke deposition and had the lowest deactivation rate of 0.008 h^–1.