H_(2)O_(2)对O_(3)-PMS体系降解碘帕醇的效能优化

Optimization of H_(2)O_(2) on degradation of IPM in O_(3)-PMS system

碘化造影剂(ICMs)作为一种典型的药品和个人护理品(PPCPs)广泛应用于医疗行业,常规的水处理工艺很难将其有效去除,而目前报道中多采用的高级氧化工艺也仍存在不足.以碘帕醇(IPM)为例,通过实验模拟研究O_(3)、O_(3)-PMS、O_(3)-PMS-H_(2)O_(2)3种高级氧化体系的降解规律及消毒副产物生成情况,探究了H_(2)O_(2)浓度、初始pH、氯离子、碳酸氢根离子、有机质对IPM降解效果的影响,并对IPM的可能降解途径进行了分析.结果表明,在O_(3)-PMS体系中投加H_(2)O_(2)可以提升对IPM的降解效率,还能减少溴酸盐的产生;O_(3)-PMS-H_(2)O_(2)体系在不同pH条件下对IPM均表现出良好的降解效果;Cl^(-)、天然有机质的存在对O_(3)-PMS-H_(2)O_(2)体系均具有抑制作用;CO_(3)^(2-)/HCO_(3)−形成缓冲体系则可以显著促进IPM的降解;O_(3)-PMS-H_(2)O_(2)体系可以通过强氧化作用和取代脱碘的路径将IPM进行有效降解.本研究可以为ICMs污染水体的修复提供理论依据.

Iodinated contrast agents(ICMs)such as iopamidol(IPM)are widely used in pharmaceutical and personal care products(PPCPs)and are difficult to be effectively removed by conventional water treatment processes.In this study,we investigated the degradation effects of different oxidation systems on IPM and the generation of disinfection by-products.The effects of H_(2)O_(2) concentration,initial pH,Cl^(−),CO_(3)^(2-)/HCO_(3)^(−) and natural organic matter on IPM degradation were studied,and the possible degradation pathways of IPM were further discussed.The results showed that adding H_(2)O_(2) into the O_(3)-PMS system can enhance the degradation efficiency of IPM and narrow the generation of disinfection by-products.The O_(3)-PMS-H_(2)O_(2) system showed a good degradation effect on IPM under pH conditions range 4 to 10.The presence of Cl^(-)and NOM inhibited O_(3)-PMS-H_(2)O_(2) system,while the CO_(3)^(2-)/HCO_(3)−significantly promoted the degradation of IPM with their pH buffer effect.The intermediate degradation products results showed the IPM could be effectively degraded by the O_(3)-PMS-H_(2)O_(2) system through radical oxidation and deiodination.The results are expected to provide a theoretical basis for the remediation of ICMs-polluted water.