Performance of CeO2-Z/O3 catalytic oxidation system for pre-treatment of wastewater containing organic peroxides

Abstract This study aims to optimize the preparation conditions of CeO2-zeolite (CeO2-Z) catalyst and its application in the CeO2-Z/O3 catalytic oxidation system for pretreatment of wastewater containing organic peroxides. Through the response surface experiment method, the single-factor influence degree and interactive influence degree of the concentration of Ce3+, exchange duration, and exchange number of the preparation catalyst CeO2-Z, as well as the optimization of these preparation conditions, were analyzed. The experimental results indicate that the optimal preparation conditions for the CeO2-Z catalyst are a Ce3+ concentration of 0.25 mol/L, a water bath duration of 16 h, and an impregnation number of 2. The catalyst prepared under these conditions exhibited excellent performance and had low economic cost. When the catalyst is applied to the pretreatment of ozone-catalyzed oxidation wastewater containing organic peroxide, the removal efficiencies of chemical oxygen demand (COD) and Ultraviolet absorbance at 254 nm (UV254) are 33.42% and 23.81%, which shows that the removal effect is good. The CeO2-Z catalyst was characterized by X-ray diffraction (XRD) and energy-dispersive spectroscopy (EDS), and the results showed that CeO2 was successfully attached to the zeolite. The five-day biological oxygen demand (BOD5) and COD ratio (B/C) of the wastewater treated with CeO2-Z/O3 catalytic system pre-treatment increased from 0.093 to 0.105 to 0.154–0.158, indicating that the CeO2-Z catalyst can significantly improve the biodegradability of the wastewater. In conclusion, the CeO2-Z catalyst shows great promise for application in the ozone catalytic oxidation pretreatment of wastewater containing organic peroxides due to its straightforward preparation process and exceptional performance.