Nitrogen-modified activated carbon supported bimetallic gold–cesium(i) as highly active and stable catalyst for the hydrochlorination of acetylene

Abstract

In the challenging acetylene hydrochlorination to vinyl chloride over Au-based catalysts, Au–Cs^I catalysts are substantially more active and stable than their monometallic counterparts. Here we describe a novel nitrogen-modified activated carbon supported Au–Cs^I catalyst (1Au4Cs^I/NAC) that delivers stable performance for acetylene conversion reaching 90.1% and there was only 1.5% C₂H₂ conversion loss after 50 h under the reaction conditions of C₂H₂ hourly space velocity 1480 h⁻¹. After a careful characterization of all the catalysts, we concluded that the nitrogen atoms’ influence on the stability of the Au–Cs^I catalysts correlates with the strengthening of the adsorption of hydrogen chloride to the catalyst and consequently inhibits Au³⁺ reduction under the reaction conditions.