Promotion of rapid microwave-assisted synthesized porous manganese-cobalt catalyst on low-temperature toluene oxidation

A series of crystalline porous materials MnCo2O4.5 catalysts were successfully synthesized by a one-step rapid microwave-assisted hydrothermal method (WH) with different microwave efficiency and duration time, which brings better catalytic activity compared with the catalyst MnCo2O4 synthesized by conventional hydrothermal method (CH). The microwave effect could attribute larger specific surface area and exposure more active sites by the Hot Spot effect during the synthesis process. The good activity of porous metal oxides MnCo2O4.5 also comes from the large total pore volume, and abundant oxygen vacancies, according to the characterization results. The difference in toluene catalytic oxidation activity between the samples was investigated using the removal rate and the mineralization rate as assessment criteria. The results shows that the temperature required for complete removal of toluene is as follows: MnCo2O4.5: 200 ℃; MnCo2O4: 250 ℃. The temperature of the total mineralization of toluene is as follows: MnCo2O4.5: 250 ℃; MnCo2O4: 275 ℃. Besides, the best synthesis condition of the catalyst is 250 W (microwave power) and 20 min (microwave time). Therefore, the microwave-assisted method has successfully synthesized crystalline porous materials and achieved excellent catalytic oxidation performance of toluene, and the unique surface characteristics of the catalyst facilitate the catalytic oxidation reaction under the Marse-van Krevelen mechanism.