摘要
文中研究了氯化过程中不同结构氟喹诺酮类(FQs)药物与氯的反应性及其在紫外/氯强化处理下的去除情况。研究分别选取叔胺甲基哌嗪[左氧氟沙星(LVF)]、叔胺乙基哌嗪[恩诺沙星(ENR)]及仲胺哌嗪结构物质[环丙沙星(CIP)]为目标污染物。结果表明,在单独氯化过程中,pH值为7、氯投加量为75μmol/L时,LVF、ENR、CIP在2 min时去除率分别为96.4%、91.5%、10.3%,其对应反应过程中氯的消耗分别为87.07%、58.57%、23.33%,呈现显著的选择性反应特性,即叔胺甲基哌嗪>叔胺乙基哌嗪>仲胺哌嗪。pH可以通过改变物质形态(HOCl、ClO-和FQs离子形态)、自由基的产生来影响FQs的降解。结果表明,当pH值为7时,FQs降解效果最佳。由于单独氯化作用下仲胺结构FQs降解缓慢(仅为18.32%),通过紫外氯耦合的技术强化对FQs的处理。结果表明,紫外/氯可显著提高仲胺哌嗪结构FQs的降解效率(增至96.29%),水基质中自然有机质(NOM)和NO_(3)^(-)会对CIP降解产生抑制作用,而Cl-和HCO_(3)^(-)对其影响较小,且在高浓度下会对CIP的降解有轻微促进作用。
This study investigated the reactivity of different FQs'structures with chlorine and the enhanced removal of primary amine FQ by UV/chlorine.The tertiary amine methylpiperazine(levofloxacin,LVF),tertiary amine ethylpiperazine(enrofloxacin,ENR)and secondary amino piperazine(ciprofloxacin,CIP)were selected as the target compounds.The results showed that the removal rates of LVF,ENR and CIP in 2 min were 96.4%,91.5%and 10.3%,respectively.With the chlorine dosage of 75μmol/L,the consumptions of chlorine at pH value 7 were 87.07%,58.57%and 23.33%,showing selective oxidation towards FQs(tertiary amine methylpiperazine>tertiary amine ethylpiperazine>secondary amine piperazine).pH value can affect the degradation of FQs by changing the species forms(HClO,ClO-and FQs ion form)and the generation of free radicals.The optimal degradation efficiency of FQs was obtained at pH value 7.The primary amine FQ of CIP was recalcitrant by chlorination treatment and only 18.32%removal efficiency was obtained.Therefore,the combination of UV and chlorine was applied here to degrade CIP.The results showed that CIP degradation was increased to 96.29%by UV/chlorine.The natural organic matter(NOM)and NO_(3)^(-) could inhibit the degradation of CIP.Cl^(-) and HCO_(3)^(-) had little impact on CIP degradation,which could even promote CIP degradation under high concentration.
作者
沈芸
赵世荣
商伟伟
钱雅洁
SHEN Yun;ZHAO Shirong;SHANG Weiwei;QIAN Yajie(College of Environmental Science and Engineering,Donghua University,Shanghai 201620,China)
出处
《净水技术》
CAS
2022年第11期55-61,共7页
Water Purification Technology
基金
国家自然科学基金(52170069)。
关键词
氯化
氟喹诺酮类
降解
紫外
选择性氧化
chlorination
fluoroquinones(FQs)
degradation
UV
selective oxidation
