Styrene removal by low-temperature catalytic oxidation using Mn₂O₃/Al₂SiO₅

Highly efficient catalytic oxidation for the removal of volatile organic compounds (VOCs) is commonly accompanied by considerable energy demand to conduct the reaction at high temperature. Therefore, the development of low-temperature catalytic oxidation systems based on metal oxides has attracted widespread interest. In this study, we have assessed the performance of Mn₂O₃/Al₂SiO₅ in catalyzing the oxidation of styrene. Tests were conducted in a fixed-bed reactor with different loadings of the supported catalyst under different operating conditions (concentration of styrene, oxygen availability, space velocity, and temperature). The characteristics of the catalyst and the reaction kinetics have been studied in detail. The best catalytic activity was achieved with 38 wt% Mn₂O₃/Al₂SiO₅, which gave 95% styrene conversion (T₉₅) at 298 °C. A space velocity of 5000 h⁻¹ provided sufficient reaction time and favored the oxidation of styrene. The absence of O₂ significantly suppressed styrene conversion to 25.4%, but the presence of just 1% O₂ substantially enhanced its catalytic oxidation. A lower reaction temperature of 282 °C led to reduced performance of the catalyst, such that only 20% styrene conversion was achieved, which was due in part to extensive carbon deposition.