Dehydrogenation of Propane to Propylene with Highly Stable Catalysts of Pt-Sn Supported Over Mesoporous Silica KIT-6

Abstract

Abstract During several reactions, similar to dehydrogenation of propane to propylene, coke is one of the main reasons for the catalyst deactivation. The coke formation and further deactivation of the catalyst are strongly dependent to the active site in the catalyst and/or the properties of the support. KIT-6 with interconnected porous and high surface area can handle with the coke formation, and can disperse easily the deposited Pt nanoparticles. In this sense, a series of Pt-Sn/KIT-6 catalysts were synthesized with distinct Sn loadings and used in the dehydrogenation of propane. The performance of these catalysts during reaction varied with the Sn loading. The specific activities for propylene formation obtained with the catalysts were comparable to the best result reported in the literature. The nanoparticles present in the catalyst through pretreatment and reaction condition was the Pt-Sn alloy (1:1 atomic ratio), and that alloy is suggested to be the active phase. This Pt-Sn alloy was stable during the entire reaction time, that even in two catalysts containing a considerable amount of coke, deactivation was not observed. Also, the support (KIT-6) with high connectivity helped to avoid deactivation by coke.