Promoting oxidative activity and stability of CeO2 addition on the MnOx modified kaolin-based catalysts for catalytic combustion of benzene

- NaY-type zeolite crystal (KL-NY) with large SBET and Vp was prepared as support.
- Highly dispersed MnOx and CeO2 modified KL-NY catalysts was prepared.
- High activity is related to improved structure and highly dispersed active sites.
- 10%MnCe(9:1)/KL-NY exhibits the highest activity and stability for benzene oxidation.

In this paper, a new kaolin-based NaY-type zeolite crystal (KL-NY) material was synthesized through in-situ crystallization, and CeO2-modified KL-NY-supported manganese oxide catalysts (MnCeOx/KL-NY) were further prepared and investigated for benzene combustion. The texture-structure, surface morphology, dispersion of active components and the redox properties of the materials were systematically characterized and analyzed by the techniques of N2 adsorption-desorption, high resolution transmission electron microscopy (HRTEM)-energy dispersive spectroscopy (EDS) as well as the H2 temperature-programmed reduction (H2-TPR). The results showed that the calcinated and crystallized KL-NY support exhibited good thermal stability with large specific surface area and large pore volume. The MnCe/KL-NY catalysts exhibited excellent deep oxidation properties. Among them, 10%MnCe(9:1)/KL-NY displayed the highest catalytic activity and could completely oxidize low-concentration benzene at 260 °C; its activity did not decrease after continuous reaction for 800 h, indicating its high potential for industrial application. The improved catalytic properties of the MnCe/KL-NY catalysts were mainly related to the higher oxidation state of MnOx and the preferable redox properties, resulted from the highly dispersion of CeO2 and MnOx on the surface of KL-NY as well as their strong interaction.

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