In this work, various Co
3O
4-ZSM-5 catalysts were prepared by the microwave hydrothermal method (MH-Co
3O
4@ZSM-5), dynamic hydrothermal method (DH-Co
3O
4@ZSM-5), and conventional hydrothermal method (CH-Co
3O
4/ZSM-5). Their catalytic oxidation of dichloromethane (DCM) was analyzed. Detailed characterizations such as X-ray diffractometer (XRD), scanning microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET), H
2 temperature-programmed reduction (H
2-TPR), temperature-programmed desorption of O
2 (O
2-TPD), temperature-programmed desorption of NH
3 (NH
3-TPD), diffuse reflectance infrared Fourier-transform spectra with NH
3 molecules (NH
3-DRIFT), and temperature-programmed surface reaction (TPSR) were performed. Results showed that with the assistance of microwave, MH-Co
3O
4@ZSM-5 formed a uniform core-shell structure, while the other two samples did not. MH-Co
3O
4@ZSM-5 possessed rich surface adsorbed oxygen species, higher ratio of Co
3+/Co
2+, strong acidity, high reducibility, and oxygen mobility among the three Co
3O
4-ZSM-5 catalysts, which was beneficial for the improvement of DCM oxidation. In the oxidation of dichloromethane, MH-Co
3O
4@ZSM-5 presented the best activity and mineralization, which was consistent with the characterizations results. Meanwhile, according to the TPSR test, HCl or Cl
2 removal from the catalyst surface was also promoted in MH-Co
3O
4@ZSM-5 by their abundant Brønsted acid sites and the promotion of Deacon reaction by Co
3O
4 or the synergistic effect of Co
3O
4 and ZSM-5. According to the results of
in situ DRIFT studies, a possible reaction pathway of DCM oxidation was proposed over the MH-Co
3O
4@ZSM-5 catalysts.
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