Zeolite supported ionic liquid catalysts for the hydrochlorination of acetylene

Abstract

An efficient and stable heterogeneous Zeolite Supported Ionic Liquid Catalyst (IL/CaX) has been explored in acetylene hydrochlorination reaction. The IL/CaX catalyst exhibits excellent space time yields of vinyl chloride (VCM), when compared to the benchmark of Au/C systems. Through characterization and kinetic studies, the reaction follows a two-site mechanism, which is described as the adsorbed hydrogen chloride on the Ca2+ in zeolite, reacting with the adsorbed acetylene on the cation of ionic liquid to form vinyl chloride. The catalytic reaction takes place at the IL/CaX interface, whilst the upper interphase IL/CaX is not active. The deactivation of the catalyst is caused by the dissolving byproducts in the ionic liquid layer, which can be reactivated by a simple vacuum procedure. It is of great significance to study and develop green non-mercury catalysts, in acetylene hydrochlorination.