Activated‐Carbon‐Supported Gold–Cesium(I) as Highly Effective Catalysts for Hydrochlorination of Acetylene to Vinyl Chloride

The synthesis of vinyl chloride from acetylene by hydrochlorination has gained tremendous interest in coal‐based chemistry. Bimetallic gold–cesium(I)/activated carbon (AuCs I /AC) catalysts were found to have a higher catalytic activity and stability for acetylene hydrochlorination when compared with gold catalysts. Over 1 Au4 Cs I /AC catalysts, the maximum conversion of acetylene was 94 % and there was only 5 % C 2 H 2 conversion loss after 50 h of running time. Moreover, the 1 Au4 Cs I /AC catalyst delivered a stable performance during a 500 h test with the conversion of acetylene and the selectivity of vinyl chloride reaching more than 99.8 and 99.9 %, respectively. Temperature‐programmed reduction of H 2 , temperature‐programmed desorption of C 2 H 2 , and X‐ray photoelectron spectroscopy techniques were further applied to detect structural information on the AuCs I /AC catalysts. Additives of CsCl indeed stabilized the catalytically active Au 3+ species and inhibited the reduction of Au 3+ to Au 0 , thereby improving the activity and long‐term stability of gold‐based catalysts.