Catalytic ozonation of penicillin G in aqueous phase using modified natural zeolite supported cerium

Cerium-loaded treated nature zeolite (Ce-NZ) was prepared by equal volume impregnation method and was used as a catalyst for the ozonation of Penicillin G (PCN) in aqueous solution.The catalyst was characterized by particle surface area analysis (BET), scanning electron microscopy combined with energy dispersive spectrum (SEM-EDS), transmission electron (TEM) and X-ray diffraction (XRD). Characterizations results suggested that the prepared samples retained the surface structure of natural zeolite and the CeO₂ particle was evenly loaded on the surface of zeolite supports. Ce-NZ catalytic ozonation of PCN in water showed that the catalyst had good catalytic activity. Under the conditions of PCN concentration 50 mg/L, ozone dosage 6 mg/min and reaction time 2 h, the mineralization efficiency of 4% Ce-NZ catalyst for PCN catalytic ozonation reached 31%, 22% higher than ozonation reaction alone. The catalytic activity of the samples slowly increased with metal loading amount and the 4% Ce loading amount was chosen as the optimum condition. The initial pH of the solution also had significant effect on the reaction, and the catalytic oxidation removal rate increased with the increasing of pH. The prepared Ce-NZ catalyst had high stability, and no marked difference of catalytic activity was seen after 10 times repeated use.