Catalytic oxidation of vinyl chloride emission over LaMnO3 and LaB0.2Mn0.8O3 (B = Co, Ni, Fe) catalysts

The LaMnO3 and LaB0.2Mn0.8O3 (B = Co, Ni, Fe) perovskite-type oxides were prepared by the conventional co-precipitation method and studied as catalysts for the oxidation of vinyl chloride emission in the temperature range of 50–350 °C. Their physicochemical properties were characterized by ICP-AES, N2 adsorption, XRD, H2-TPR, O2-TPD and XPS. Catalytic performances were evaluated for the oxidation of 1000 ppm of VC in air at a GHSV of 15,000 h−1. The substituted LaB0.2Mn0.8O3 samples showed higher catalytic activity than pure LaMnO3. Characterization results revealed that the catalytic activity of the perovskite oxides was greatly related to the low-temperature reducibility of the B site and the amount of adsorbed oxygen species and vacancies on the surface. The surface adsorbed oxygen species played a key role in the catalytic reaction and oxygen vacancies promoted the oxygen mobility. A reaction mechanism of vinyl chloride oxidation over LaMnO3-based perovskite oxides was proposed.

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► LaMnO3 and LaB0.2Mn0.8O3 (B = Co, Ni, Fe) were prepared by co-precipitation method.
► The B-site substitution increased the amounts of Mn4+ on the surface.
► No by-products were formed but only CO2, H2O and HCl.
► LaNi0.2Mn0.8O3 presented the best catalytic activity for vinyl chloride abatement.
► Reducibility, surface adsorbed oxygen and O2 mobility were the main parameters.