Fe Doped ZIF-8 Derivative To Activate Peroxymonosulfate For Degradation Of Sulfamethoxazole

Sulfonamides antibiotics are widely used in the fields of agriculture,animal husbandry,aquaculture and hospitals.After traditional water treatment technology,a large number of residues are still in the water environment.The residue of sulfonamide antibiotics in the environment for a long time will induce the life to produce resistance genes,which will cause serious harm to human and ecological environment.At present,heterogeneous persulfate advanced oxidation technology has been widely used,but there is a phenomenon of metal dissolution.Therefore,it is the primary goal of water treatment technology to develop a high efficient and feasible method to remove sulfamethoxazole.In this paper,sulfamethoxazole（SMX）,a typical sulfonamide antibiotic,was used as the target pollutant to investigate the degradation efficiency and influencing factors of activated PMS by synthesized MOFs derivative(Zn₄₀Fe-NC).（1）Fe-ZIF-8 derivative catalyst optimization experiment:MOFs derivatives with different iron doping amount were prepared by"one pot"method.The Zn₄₀Fe-NC with the best performance was selected as the follow-up experimental material.The materials were characterized by SEM,TEM,XRD,BET,Raman and XPS（2）Study on degradation of SMX by PMS activated by Zn₄₀Fe-NC:the optimal reaction conditions were optimized by single factor experiment,the amount of catalyst was 150 mg/L,the amount of PMS was 0.5 m M,the initial p H was 5.6,and the concentration of SMX solution was 5 mg/L.The effects of different inorganic anions and typical natural organic compounds in water on the degradation of SMX by Zn₄₀Fe-NC/PMS system were studied.The stability of the catalyst was evaluated by two experiments,and it was found that the degradation effect of the catalyst was still very stable after repeated five experiments.The degradation effect of Zn₄₀Fe-NC/PMS system was still very good in lake water and natural water,and it was selective for target pollutants,such as sulfamethoxate,bisphenol A,sulfaisoxazole and ciprofloxacin.（3）Degradation mechanism and path of Zn₄₀Fe-NC activated persulfate:the quenching experiment,EPR characterization and related non free radical experiments verified that Zn₄₀Fe-NC/PMS system mainly through the non-radical pathway of singlet oxygen and high valent iron reactive oxygen species to degrade SMX.Through HPLC/MS-MS analysis,four kinds of intermediate products were detected and four possible degradation pathways were speculated.