Synthesis of manganese ore/Co3O4 composites by sol–gel method for the catalytic oxidation of gaseous chlorobenzene

Abstract

Manganese ore/cobalt oxide composites were synthesized by using natural manganese ore and Co(NO3)2·6H2O via oxalic acid-assisted sol–gel method and applied in the catalytic oxidation degradation of gaseous chlorobenzene. The catalytic properties of the manganese ore/Co3O4 composites were investigated by X-ray diffraction (XRD), the electron microscopy technique (FE-SEM), N2 adsorption–desorption (BET), X-ray photoelectron spectroscopy (XPS) and H2-temperature programmed reduction (H2-TPR), respectively. The results showed that the composite catalyst with the mass ratio of manganese ore/cobalt oxide was 0.4 and calcined at 450 °C had the optimal catalytic performance. It could achieve 94% conversion of chlorobenzene, 83% selectivity of CO2 and over 36 h sustainability at 300 °C for the gaseous chlorobenzene with the initial concentration of 1200 mg m−3. The composite catalyst had the abundant surface oxygen species, good anti-chlorine poisoning performance and strong redox properties of composites, which were due to the interaction between manganese ore and Co3O4, and played a key role in degradation of chlorobenzene.