Promotion Effect of Microwave-Assisted Prepared Porous Fe–Mn Catalyst on Toluene Removal

Fe–Mn oxide is widely used for VOCs catalytic oxidation due to its advantages of low cost and easy availability. However, the low-temperature catalytic oxidation activity of Fe–Mn oxide is limited. In order to prepare a porous Fe–Mn oxide for VOCs oxidation with high efficiency and stability at low temperatures, a microwave-assisted oxalate co-precipitation method is used to prepare porous Fe 2 Mn 1 -MW catalysts, the physicochemical properties of the prepared porous Fe 2 Mn 1 -MW, such as surface structure, element composition, redox performance, oxygen mobility and oxidation activity, are compared with the porous Fe 2 Mn 1 prepared by the conventional oxalate co-precipitation method. The results indicate that the porous Fe 2 Mn 1 -MW catalyst with microwave-assisted exhibits higher toluene conversion with a T 90% of 213 °C under WHSV of 40,000 ml g −1 h −1 . Meanwhile, the porous Fe 2 Mn 1 synthesized by microwave-assisted oxalate co-precipitation method has excellent thermal stability and steam tolerance even under RH of 50 vol% steam atmospheres within 60 h. Characterization results demonstrate that the microwave post-processing can not only enlarge the BET surface area and generate oxygen vacancies derived from interface defects, but also enhance acid properties, redox properties and the oxidation state, thereby leading to the excellent activity and stability of the as-obtained porous Fe 2 Mn 1 -MW. Graphical Abstract