Strong metal-support interaction enhanced acetylene hydrochlorination stability over Cu1-N-C single-site catalysts

Cu-based catalysts present a promising alternative to toxic mercuric chloride (HgCl 2 ) in acetylene hydrochlorination owing to their cost-efficiency and environmental compatibility. However, the dispersion and leaching of active sites under operational conditions hinders its application. Herein, we designed a lignin-supported Cu 1 N single-site copper catalyst (Cu 1 /L-CN) by site-anchored strategy which employed pyrrolic N functional groups to anchor and inhibit the aggregation of Cu atoms by strong metal-support interaction. Based on kinetics study and in-situ characterizations, it is found that the Cu 1 /L-CN catalyst inhibits the formation of complexes between copper and acetylene, suppressing over-adsorption of acetylene and undesired side reactions. Accordingly, the Cu 1 /L-CN catalyst demonstrated excellent catalytic activity and a low deactivation rate constant (k D  = 0.016 h −1 ) with significantly reduced carbon deposition. This work will provide a new approach to the design of mercury-free catalysts toward industrial production of vinyl chloride from the acetylene hydrochlorination.