Progress of catalytic oxidation of VOCs by manganese-based catalysts

Abstract

Previous studies have confirmed that catalytic oxidation is a promising and effective technology for treating volatile organic compounds (VOCs). Manganese-based catalysts are characterized by high catalytic activity, relatively low cost, long durability, structural diversity. And as an environmentally friendly material, they are therefore one of the most competitive materials in the field of catalytic oxidation of volatile organic compounds. Despite the potential for a wide range of applications, the use of manganese-based catalysts is limited by deactivation and sintering sensitivity, which may affect their long-term performance thus limiting their use in industry. In this paper, we summarize the relevant progress of the current research from four aspects: single manganese oxides, composite manganese-based oxides, acid-treated manganese catalyst surfaces, and Mn-based perovskite catalysts. Compared to single manganese oxides, manganese-based composite catalysts exhibit enhanced activity and stability due to synergistic interactions between the metals. And adjusting the carrier can obtain a larger specific surface area, better dispersion of metal active sites, and enhance the synergistic interaction between the active sites and the carrier, thus obtaining better catalytic performance. Acid treatment, on the other hand, can change the catalyst surface chemistry such as metal oxidation state, reactive oxygen species and structural defects, and Mn-based perovskite are widely used due to their flexible composition, good redox properties, good thermal stability, and relatively low price. Finally, the problems and prospects of Mn-based oxide catalysts for catalyzing the combustion of VOCs are presented to provide ideas for further design of new and efficient low-temperature catalysts.