Enhancement of catalytic combustion of toluene over CuMnOx hollow spheres prepared by oxidation method

Abstract

Catalytic oxidation is considered as one of the most potential technologies for complete removal of VOCs. It is generally accepted that the development of catalyst with high and stable activity at low temperature is the key for such a catalytic strategy. The CuMnO x catalyst with a hollow spherical structure (CuMnO x -HS) was successfully prepared by an oxidation strategy and applied to toluene removal. Combined with the results of XRD, SEM, TEM, HRTEM, BET, H 2 -TPR, XPS and O 2 -TPD, the enhanced synergistic effect between Mn and Cu originating from the special oxidation method resulted in the large specific surface area, enhanced reducibility, and oxygen mobility as well as abundant adsorbed oxygen species of CuMnO x -HS, which was responsible for its superior catalytic performance. CuMnO x -HS could achieve a toluene conversion of 90% at 212 °C. Furthermore, CuMnO x -HS showed a stable removal efficiency and excellent water resistance, suggesting a great potential in practical application for the complete removal of toluene. CuMnO x catalyst with a hollow spherical morphology (CuMnO x -HS) was successively synthesized by in-situ oxidation of Cu 2 O nanospheres. The CuMnOx-HS catalyst achieves a toluene conversion of 100% at 220 °C, and shows super-stable removal efficiency and water resistance, indicating a great potential in practical application for the total oxidation of toluene. • CuMnO x hollow spheres (CuMnO x -HS) were prepared by in-situ oxidation of Cu 2 O. • The stepwise oxidation of Cu 2 O spheres facilitated the Cu 2+ -O 2− -Mn 4+ entities. • CuMnO x -HS showed a super-stable removal efficiency and good resistance to water. • The enhanced reducibility and oxygen mobility were responsible for the superior activity of CuMnO x -HS.