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Among the vinyl chloride production processes, ethane oxychlorination is the most economical and environment-friendly process but constrained by the lack of high performance catalysts for industrial applications. In this work, FeCl3–KCl/Al2O3 catalysts with different molar ratios of K/Fe were prepared by a co-impregnation method and applied to ethane oxychlorination. The FeCl3–KCl/Al2O3 catalyst with K/Fe = 2 exhibited enhanced catalytic performance with the highest conversion of C2H6 (99.1%) and the best selectivity to C2H3Cl (74%) under the optimal conditions of 400 °C, C2H6 : HCl : air = 1 : 3 : 5.5 (volume ratio) and GHSV = 4560 h−1. It was found that the enhanced catalytic performance could be attributed to the formation of KFeCl4 from KCl and FeCl3 and the change of the reaction process. Besides, KCl is in favor of weakening the interaction between the active species and support. The reduction activation energy of Fe(iii) → Fe(ii) is efficiently reduced by KCl addition. The FeCl3–KCl/Al2O3 catalyst may be a potential catalyst for industry due to its simple composition and convenient preparation. [ABSTRACT FROM AUTHOR]

Supported perovskite promoted catalysts La 2 NiMnO 6 –CuCl 2 /γ-Al 2 O 3 and La 1.7 K 0.3 NiMnO 6 –CuCl 2 /γ-Al 2 O 3 were prepared by mechanical mixing method, and characterized by XRD, H 2 -TPR, XRF, XPS and magnetization techniques. The catalyst doped with potassium La 1.7 K 0.3 NiMnO 6 –CuCl 2 /γ-Al 2 O 3 possesses a large amount of Mn 4+ and surface-adsorbed oxygen species, which accelerate the oxidation of Cu + by a circular reaction and increase the release of Cl 2 , and therefore promote the conversion of C 2 H 6 and the selectivity to C 2 H 3 Cl. The catalyst La 1.7 K 0.3 NiMnO 6 –CuCl 2 /γ-Al 2 O 3 shows better catalytic activity for ethane oxychlorination with the C 2 H 6 conversion of 100% and the C 2 H 3 Cl selectivity to 59.4%. The total selectivity to C 2 H 4 and C 2 H 3 Cl maintains over 81% in 95 h. This study points out a potential way to develop more active perovskite-type oxide catalysts for ethane oxychlorination. [ABSTRACT FROM AUTHOR]