Metal –organic framework‐derived cobalt and nitrogen co‐doped porous carbon with four‐coordinated Co–Nx for efficient acetylene hydrochlorination

Introducing a small amount of Co to N ‐doped carbon can significantly improve the catalytic activity for acetylene hydrochlorination due to the fact that the generated Co‐N4 has a stronger ability to adsorb and activate acetylene. Industrial production of vinyl chloride through acetylene hydrochlorination is a dominating technique in coal ‐rich areas, but its development is severely restricted by the use of toxic mercury chloride (HgCl2) catalyst. Inspired by the fact that doped carbon materials active in acetylene hydrochlorination often have good performance in the oxygen reduction reaction, a series of cobalt and nitrogen co ‐doped porous carbon catalysts prepared by pyrolysis of bimetallic ZIFs based on ZIF‐8 and ZIF‐67 under N2 were applied in acetylene hydrochlorination. The catalytic activities of the co ‐doped catalysts varied with Co addition, and the highest acetylene conversion could be up to 83% with a space velocity of 2.6 ml g−1 min−1 at 220 °C when a small amount of cobalt was introduced. Results of several characterizations confirmed the existence of Co–Nx in the co ‐doped carbons, pointing out that this coordination structure makes the catalysts have better ability to adsorb and activate C2H2. Density functional theory calculation finally proved that C atom adjacent to the N atom in Co –N4 structure is the primary active site in co ‐doped catalysts with high activity. We also conclude that the decreased N content caused by Co2N d...

Source: Applied Organometallic Chemistry - October 25, 2018 Category: Chemistry Authors: Xiaobin Dong, Chaoyue Zhao, Qingxin Guan, Wei Li, Xiufang Xu Tags: FULL PAPER Source Type: research