CoFe2O4增强超声/H2O2降解环丙沙星

Enhanced ultrasonic/H_2O_2 degradation of ciprofloxacin using CoFe_2O_4

实验合成磁性CoFe_2O_4,采用X射线衍射仪(XRD)、扫描电镜(SEM)和X射线能谱仪(EDS)对其进行表征,研究其催化超声/H_2O_2(US/H_2O_2)降解环丙沙星的效果和机理.实验考察了CoFe_2O_4和H_2O_2添加浓度、初始p H值、不同形态氮、氯离子等因素对环丙沙星降解效果的影响.并以大肠杆菌为指示菌种,分析了CoFe_2O_4催化US/H_2O_2降解环丙沙星过程中抑菌性的变化.结果表明,CoFe_2O_4能够有效增强US/H_2O_2降解环丙沙星,CoFe_2O_4和H_2O_2浓度分别为0.04 g·L^(-1)和1.0 mmol·L^(-1)、p H=3.0、反应60 min环丙沙星的降解率达到85.26%;与NH_4^+相比,NO_3^-促进环丙沙星的降解,NO_2^-和Cl^-不同程度抑制环丙沙星的降解.自由基抑制结果表明,CoFe_2O_4增强US/H_2O_2降解环丙沙星主要在于·OH的生成.CoFe_2O_4稳定性结果表明,5次反复实验后,环丙沙星60 min的降解率仅降低了4%左右,催化剂的重复利用性较高.琼脂扩散实验表明,CoFe_2O_4在催化US/H_2O_2降解环丙沙星的同时,CoFe_2O_4/US/H_2O_2体系能够完全去除其对大肠杆菌的抑菌性.

Magnetic iron cobalt CoFe2O4was synthesized,characterized by XRD、SEM and EDS methods.Its enhancement and mechanism on ciprofloxacin degradation under ultrasound/H2O2system were studied.The parameters such as CoFe2O4and H2O2concentration,initial pH value,different forms of nitrogen and chloride ions on ciprofloxacin degradation were investigated.In addition,ciprofloxacin antibacterial activity on E.coli was analyzed.The results indicated that CoFe2O4enhanced ciprofloxacin degradation under US/H2O2system effectively.Ciprofloxacin degradation rate reached 85.26%in 60 min when CoFe2O4and H2O2concentration were 0.04 g·L^（-1）and ciprofloxacin degradation while NO2^-and Cl^-showed inhibition.Radical scavenging experiments indicated that the catalytic enhancement was mainly attributed to the generation of hydroxyl radical（·OH）.The repeated tests showed that CoFe2O4presented good stability.Ciprofloxacin degradation rate only decreased by 4%even after five cycles.Agar diffusion test revealed that CoFe2O4effectively enhanced ciprofloxacin degradation under US/H2O2system,and ciprofloxacin antibacterial activity on E.coli was completely removed.