Catalytic ozonation of antipyrine with a magnetic core/shell CeO2 catalyst: kinetics and mechanism

In this study, antipyrine was selected as the typical pharmaceutical and personal care products (PPCPs) and the abatement of antipyrine was investigated by the catalytic ozonation with a magnetic Fe3O4@SiO2@CeO2 catalyst. Focusing on the kinetics of the antipyrine degradation at different initial concentrations of antipyrine, the ozone dosages, initial pH values, the antipyrine degradation mechanism, and catalytic mechanism was explored. The results showed that the core/shell Fe3O4@SiO2@CeO2 catalyst exhibited high activity in the degradation of antipyrine. Types of intermediates, such as anisole, nitrobenzene, n-phenylpropinamide, and aniline were detected by gas chromatographymass spectrometry and high performance liquid chromatography techniques during the catalytic ozonation process. The presence of the radical scavenger tert-butyl alcohol during catalytic ozonation promoted the degradation of antipyrine unexpectedly instead of inhibiting the generation of hydroxyl radicals from ozone decomposition. The results implied that the high removal efficiency was mainly attributed to the interfacial effect of Fe3O4@SiO2@CeO2 catalyst. The energy consumption was also analyzed and discussed. This paper could provide basic data and technique reference of catalytic ozonation for the PPCPs wastewater treatment.