Acetylene hydrochlorination to vinyl chloride monomer on Au(I) centers stabilized by pyrrole N in active carbon

Abstract

The urgent need to replace the toxic mercuric chloride (HgCl₂/AC) catalyst used in current industry for the production of vinyl chloride monomer (VCM) through acetylene hydrochlorination has been a great challenge. Although Au catalyst has been regarded as a potential catalyst for the reaction, it is unstable under reaction conditions. In this work, we report that atomically dispersed Au⁺ atoms supported on nitrogen doped carbon (Au/NC) can show high performance in the production of vinyl chloride monomer. This catalyst achieves an C₂H₂ conversion of 94.2 % and a VCM selectivity of 99.9 %, superior to Au catalyst supported on active carbon (Au/AC) without nitrogen doping. These active centers were identified to be the Au⁺ active centers, and the enhanced performance of the Au/NC catalyst is attributed to the presence of pyrrole nitrogen species, which strongly coordinate to the Au⁺ active centers promoting the adsorption and activation of C₂H₂. This research offers a promising way to stabilize the Au⁺ active centers and enhances the catalytic performance.