Department of Chemistry
Rod-, flower-, and dumbbell-like MnO2: Highly active catalysts for the combustion of toluene
The rod-like tetragonal α-MnO 2, flower-like hexagonal ε-MnO 2, and dumbbell-like tetragonal β-MnO 2 were prepared using the hydrothermal or water-bathing method under different conditions. It is shown that the α-MnO 2, ε-MnO 2, and β-MnO 2 catalysts possessed a surface area of ca. 53, 30, and 114 m 2/g, respectively. The oxygen adspecies concentration and low-temperature reducibility decreased in the order of α-MnO 2 > ε-MnO 2 > β-MnO 2, coinciding with the sequence of their catalytic activities for toluene combustion. The well-defined morphological MnO 2 catalysts performed much better than the bulk counterpart. At a space velocity of 20,000 mL/(g h), the temperature for 90% toluene conversion was 238, 229, and 241 °C over α-MnO 2, ε-MnO 2, and β-MnO 2, respectively. The apparent activation energies of α-MnO 2, ε-MnO 2, and β-MnO 2 were in the range of 20-26 kJ/mol. It is concluded that higher oxygen adspecies concentrations and better low-temperature reducibility were responsible for the good catalytic performance of the α-MnO 2, ε-MnO 2, and β-MnO 2 materials. © 2012 Elsevier B.V.
Hydrothermal preparation method, Manganese oxide catalyst, Toluene combustion, Water-bathing preparation method, Well-defined morphology
Source Publication Title
Applied Catalysis A: General
Link to Publisher's Edition
Shi, F., Wang, F., Dai, H., Dai, J., Deng, J., Liu, Y., Bai, G., Ji, K., & Au, C. (2012). Rod-, flower-, and dumbbell-like MnO2: Highly active catalysts for the combustion of toluene. Applied Catalysis A: General, 433-434, 206-213. https://doi.org/10.1016/j.apcata.2012.05.016