亚铁活化过氧乙酸降解水中磺胺甲恶唑:投药策略和反应机理  

Degradation of Sulfamethoxazole in Water by Ferrous Iron-Activated Peracetic Acid:Dosing strategy and Reaction Mechanism

作　　者：莫耀钧 隋铭皓[1] MO Yaojun;SUI Minghao(College of Environmental Science and Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学环境科学与工程学院,上海200092

出　　处：《水处理技术》2023年第6期33-38,共6页Technology of Water Treatment

基　　金：国家重点研发计划课题(2019YFC0408801)。

摘　　要：为解决传统工艺难以有效降解水中抗生素类污染物的问题,采用亚铁离子(Fe^(2+))活化过氧乙酸(PAA)氧化降解水中典型抗生素类物质磺胺甲恶唑(SMX)。考察了PAA和Fe^(2+)投加量、药剂不同投加策略对PAA活化和SMX降解的影响,并鉴定了参与反应系统的活性物种。结果发现,PAA和Fe^(2+)浓度的适当增加,能提高SMX降解效率,但过量添加会抑制降解;从一次投加改为分次投加(投加相同的总量,但在特定的时间间隔内投加)和连续投加(投加相同的总量,但在反应时间内连续投加)时,SMX的降解效率显著提高;监测体系中Fe^(2+)和PAA的浓度发现,分次与连续投加方式均改善了PAA的活化效果。自由基捕获实验结果表明,羟基自由基(HO·)、有机自由基和Fe^(IV)O^(2+)均可能参与了SMX的降解;连续投加PAA策略下,HO·对SMX降解的贡献要大于一次投加和连续投加Fe^(2+)策略。As the traditional process was difficult to effectively remove the refractory antibiotic pollutants in water,ferrous ion(Fe^(2+))activated peracetic acid(PAA)was applied to oxidize and degrade the typical antibiotic substance sulfamethoxazole(SMX)in the water.The effects of PAA and Fe2+dosing amounts and different reagent dosing strategies on PAA activation and SMX degradation processes were investigated,and the dominant active species involved in the reaction system were identified.It was found that appropriate increase of PAA and Fe^(2+)concentrations improved SMX degradation efficiency,but excessive addition inhibited the degradation.The degradation efficiency of SMX was significantly improved when changing from direct dosing to sequential dosing(dosing that same total amount but divided over specific time intervals)and continuous dosing(dosing the same total amount but continuously during the reaction time).Monitoring the concentration of Fe^(2+)and PAA in the system revealed that both sequential and continuous dosing methods promoted the activation of PAA.The results of radical quenching experiments indicated that hydroxyl radicals(HO·),organic radicals and Fe^(IV)O^(2+)may all be involved in the degradation of SMX.The contribution of HO·to the degradation of SMX was greater for continuous PAA dosing than for direct dosing and continuous Fe^(2+)dosing.

关 键 词：亚铁离子 过氧乙酸 投药策略 磺胺甲恶唑 

分 类 号：R978.1[医药卫生—药品]