Study On The Performance And Mechanism Of Degradation Of Sulfamethoxazole By CuO Modified Material/PMS Syste

As a common antibiotic,sulfamethoxazole(SMX)has been widely used to treat respiratory tract infection,intestinal infection and other diseases.Because it cannot be completely metabolized by humans or animals,once discharged into the environment,it will cause harm to the water ecosystem and human health.The degradation of antibiotics in water by advanced oxidation process based on peroxymonosulfate(PMS)activation has received extensive attention.In this study,Cu O materials with low price and easy access were prepared and modified to prepare two kinds of catalysts that can effectively activate PMS for the degradation of sulfamethoxazole,and sufficient characterization and activity research were carried out,and its mechanism was preliminarily explored.The specific research and contents are as follows:(1)Using anhydrous copper sulfate as copper source and sodium thiosulfate as sulfur source,sulfur doped copper oxide catalytic material was successfully synthesized by simple hydrothermal method.The successful synthesis of the material was proved by XRD,XPS and other characterization.The catalyst was used to activate PMS and degrade sulfamethoxazole.The results showed that the system could rapidly degrade 97.13% sulfamethoxazole in 1 minute.Both free radical and non-free radical pathways provide active species for degradation.The intermediates in the degradation process were detected by mass spectrometry and their toxicity was simulated,and two possible degradation pathways were obtained.DFT calculation shows that S-reaction can produce Cu-S-O covalent bond,promote electron transfer and further enhance the activation of PMS.(2)ZnO/CuO-3 heterojunction composites were successfully synthesized by simple hydrothermal method with zinc nitrate as zinc source and copper sulfate as copper source.The successful synthesis of the material was proved by XRD and other characterization.The catalyst was used to activate PMS and degrade sulfamethoxazole.The results showed that the system could be99.64% degraded within 30 minutes.The anion interference experiment was carried out to prove that the catalytic system is suitable for the actual wastewater environment.The main active species were obtained by free radical quenching experiment.After five cycles of experiments,the degradation rate can still reach more than 99%,indicating that the catalyst has good reusability.ICP-MS was used to detect that the leaching amounts of copper and zinc ions in the ZnO/CuO-3/SMX/PMS system were relatively low.