Deactivation factor of CuCl2-KCl/Al2O3 catalyst for ethylene oxychlorination in a commercial-scale plant

[Display omitted] •Ethylene oxychlorination over a CuCl2-KCl/Al2O3 catalyst was examined for two consecutive years in a commercial-scale plant.•Relationship between catalyst performance and physicochemical properties was investigated.•Catalyst deactivation was due to the increased K/Cu ratio caused by Cu sublimation.•The (KxCuCl2+x) phase could be increased by increased K/Cu ratio in used catalysts. Ethylene oxychlorination over a CuCl2-KCl/Al2O3 catalyst was examined for 2 consecutive years in a commercial-scale plant. The oxychlorination performance of the CuCl2-KCl/Al2O3 catalyst deteriorated gradually, which could seriously affect stable operation. To clarify such deactivation factors, the relationship between catalyst performance and physicochemical property change was investigated using X-ray fluorescence, electron probe microanalysis, and Brunauer–Emmett–Teller measurements. Sublimation of the CuCl component and subsequent increment of the ratio of K to Cu components were observed at the inlet of the catalyst bed, and were determined to be contributing factors in the deactivation of the CuCl2-KCl/Al2O3 catalyst.