The Reaction Order and Kinetics of Total Oxidation Reaction of M-xylene over LaMnO3 Perovskite Catalyst

Abstract

M-xylene, one of the popular toxic pollutants in exhaust gases, is emitted into the environment from factories and engines. The best solution for removing m-xylene to protect the environment is completely transforming it into CO₂ and H₂O by catalysts. Perovskite of LaMnO₃ is one of the catalysts that was synthesized and studied for its catalytic properties in a total oxidation reaction of m-xylene in a previous report by the authors. The results showed that the LaMnO₃ perovskite had good catalytic characterizations such as large surface area and big amount of α-oxygen adsorbed on the catalyst; more specifically, LaMnO₃ perovskite exhibited a good catalytic activity in a total oxidation of m-xylene at a relatively low reaction temperature. This study determines the reaction order and kinetics of this reaction. The results show that the reaction order with respect to m-xylene was 1; to oxygen, zero, and the general order of reaction was 1. These data show that the pathway of the named reaction followed the Langmuir–Hinshelwood mechanism.

Keywords

Catalyst, perovskite, oxidation, m-xylene, kinetics

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