Study on the effect and mechanism of Fe₂O₃-CeO₂@CM for catalytic ozonation of sulfamethoxazole in wastewater treatment

Residual sulfamethoxazole (SMX) in aquatic environments poses risks to ecosystems and human health. Due to their exceptional mechanical strength and chemical durability, ceramic membranes (CMs) provide a suitable platform for heterogeneous catalytic oxidation. The synthesis of Fe 2 O 3 -CeO 2 @CM for catalyzing ozone oxidation to remove SMX was done in this study using a hydrothermal in-situ growth technique. The findings showed that when the Fe/Ce molar ratio was 1:3, the calcination temperature was 500°C, and the catalyst loading was 8.4 mg/g, the SMX was totally removed in 10 min in the presence of Fe 2 O 3 -CeO 2 @CM. The characterisation results showed that the material comprised FeCe solid solution and Fe 2 O 3 particles, exhibiting multiple valence states (Fe 2+ /Fe 3+ , Ce 3+ /Ce 4+ ). Based on the quenching experiments, ·OH, ·O 2 - , and 1 O 2 radicals were shown to be involved, with ·O 2 - and 1 O 2 playing primary roles. Mechanistically, the Fe 2+ /Fe 3+ and Ce 3+ /Ce 4+ species in the catalyst exhibited favourable redox cycling, promoting oxygen vacancy regeneration and serving as key active sites for catalysing O 3 decomposition. Furthermore, the system demonstrated excellent cycling stability, maintaining SMX removal rates above 95% after five cycles and achieving 94% removal in actual wastewater, effectively mitigating membrane fouling. An effective and reliable technique for eliminating antibiotics from wastewater is presented in this work.