UV/H_(2)O_(2)和UV/PDS体系对磷霉素降解效果的对比

Comparison of UV/H_(2)O_(2)and UV/PDS Systems for Fosfomycin Degradation Effectiveness

紫外高级氧化技术降解有机污染物,由于操作简单、成本低、不易产生二次污染等优点被广泛应用。文章以磷霉素钠作为污染物,研究了UV/H_(2)O_(2)和UV/过硫酸盐(PDS)两种高级氧化技术对有机磷的降解特性,并对比了两种体系下有机磷的降解动力学和反应机理。试验结果表明,在UV/H_(2)O_(2)和UV/PDS体系中,UV激活氧化剂产生的活性基团可有效降解有机磷,有机磷降解率分别为97.3%和95.0%,初始pH、氧化剂投加量、反应温度均会对有机磷降解产生影响,相比于UV/H_(2)O_(2)体系,UV/PDS体系在降解有机磷时,具有pH适用范围较宽、反应温度低、氧化剂投加量小、反应速率快的优势。在最优条件下,两种体系都具有环境适应性。通过自由基捕获试验与电子顺磁共振技术(EPR)可知,UV/H_(2)O_(2)体系中存在·OH,UV/PDS体系中存在SO_(4)^(·-)和·OH。通过气-质联用(CG/MS)技术,测得两种体系降解磷霉素钠后均含有乙酸和丙酸。

UV advanced oxidation technology for organic pollutants degradation is widely used due to the advantages of simple operation,low cost and less secondary pollution.The target pollutant in this work was fosfomycin sodium,and the organic phosphorus(OP)degradation was explored using two advanced oxidation processes which were UV/H_(2)O_(2)and UV/PDS,and the kinetics and reaction mechanism of OP degradation in the two systems were compared.The research results demonstrated that the reactive groups generated by the UV-activated oxidant could effectively degrade OP in the UV/H_(2)O_(2)and UV/PDS,with 97.3%and 95.0%removal efficiency respectively.All of these variables,including the initial pH,initial oxidant concentration and reaction temperature all affected the OP degradation.In comparison with UV/H_(2)O_(2),the UV/PDS system had the advantages of wider pH application range,lower reaction temperature,less oxidant dosage and faster reaction rate when degrading OP.The best conditions were achieved through the correspondence of two systems,both of which were environmentally adaptive.The radical capture text and electron paramagnetic resonance technology(EPR)indicated that OH was present in the UV/H_(2)O_(2)system,while both SO_(4)^(·-)and·OH were present in the UV/PDS system.Gas chromatography-mass spectrometry(CG/MS)determined that both systems contained acetic acid and propionic acid after degrading fosfomycin sodium.