Synergistic Effect of ZSM-5 Zeolite in Pt-CeO2-TiO2/ZSM-5 Catalysts for Highly Efficient Catalytic Oxidation of VOCs

摘要

A series of Pt-CeTi/ZSM-S catalysts (0.5 wt % Pt) with different CeO2—TiO2/ZSM-5 mass ratios were synthesized and used for the catalytic oxidation of 1,2-dichloroethane and benzene. The results reveal that the strong Pt/CeO2—TiO2 interaction can be evidently enhanced by introducing proper amounts of CeO2—TiO2 mixed oxides, resulting in the improvement of Pt dispersion and redox properties as well as the production of more defective oxygen and Pt2+ species. The synergistic effect between abundant ZSM-5 acid sites (especially strong acid sites) and strong Pt/CeO2—TiO2 oxidizing sites facilitates the deep oxidation of benzene, intermediates, and byproducts generated from the 1,2-dichloroethane oxidation process at lower temperature. Among the catalysts, Pt-CeTi/ZSM-5(1/10) with the CeO2-TiO2/ZSM-5 mass ratio of 1/10 exhibits the greatest activity for benzene and 1,2-dichloroethane oxidation, showing the T90% of 145 and 245 °C, respectively. Moreover, the catalyst also possesses satisfactory adaptability for the oxidation of various VOCs and durability for 1,2-dichloroethane oxidation.