Removal of atrazine and its by-products from water using electrochemical advanced oxidation processes
Removal of atrazine and its by-products from water using electrochemical advanced oxidation processes
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DOI：
10.1016/j.watres.2017.08.036
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发表时间：
2017-11-15
期刊：
影响因子：
12.8
通讯作者：
Lafrance, Pierre
中科院分区：
文献类型：
--
作者：
Komtchou, Simon;Dirany, Ahmad;Lafrance, Pierre
阿特拉津(ATZ)是加拿大魁北克地表水中检测到的最常见的杀虫剂之一。本文主要研究了光电Fenton(PEF)、电Fenton(EF)和同时生成H_2O_2的阳极氧化(AO-H_2O_2)等电化学高级氧化工艺对ATZ及其副产物的降解。结果表明，无论是人工合成溶液(ATZ(0)=100mgL-1)还是富含ATZ(0)的真实农业地表水(ATZ(0)=10mgL-1)，PEF工艺对ATZ及其副产物的去除效果最好。以掺硼金刚石(BDD)为阳极，石墨为阴极，考察了不同的操作参数，包括光波长、pH值、电流密度和天然有机物(腐植酸)的存在。电流密度和光的波长是影响ATZ降解效率的最重要参数。当电流密度为18.2 mA·cm~(-2)、pH为3.0、处理时间为45min时，合成样品的最佳工作条件为：电流密度18.2 mA·cm~(-2)，pH=3.0，处理时间45min。结果表明，阿特拉津-去乙基-地索丙基(DEDIA)是最重要的副产物。处理15min后，ATZ氧化率达99%以上，处理45min后，主要副产物浓度均低于检测限值。还对受ATZ污染的真实地表水进行了PEF工艺测试：i)添加和不添加铁；ii)不调节pH(pH与6.7相似)和调节pH(pH与3.1相似)。尽管存在自由基清除剂和铁络合作用，但当pH值调整到3.0时，PEF工艺对实际地表水中ATZ的去除效果更好。0.01 mm铁对ATZ的去除效果为96.0%(k(App)=0.13min(-1))，0.1 mm铁对ATZ的去除效果为100%(k(App)=0.17min(-1))。(C)2017爱思唯尔有限公司。保留所有权利。
Atrazine (ATZ) is one of the most common pesticides detected in surface water in Quebec (Canada). The present study was mainly focused on the degradation of ATZ and its by-products using electrochemical advanced oxidation processes such as photo-electro-Fenton (PEF), electro-Fenton (EF) and anodic oxidation with simultaneous H2O2 formation (AO - H2O2). The comparison of these processes showed that PEF process was found to be the most effective process in removing ATZ and its by-products from both synthetic solution (ATZ(0) = 100 mu g L-1) and real agricultural surface water enriched with ATZ (ATZ(0) = 10 mu g L-1). Different operating parameters, including wavelength of the light, pH, current density and the presence of natural organic matter (humic acids) were investigated for PEF process using boron doped diamond (BDD) anode and graphite cathode. The current density and the wavelength of the light were the most important parameters in the ATZ degradation efficiency. The best operating conditions were recorded for the synthetic samples at a current density of 18.2 mA cm(-2), a pH of 3.0 and treatment time of 45 min. Results showed that atrazine-desethyl-desisopropyl (DEDIA) was the most important by-product recorded. More than 99% of ATZ oxidation was recorded after 15 min of treatment and all the concentrations of major by-products were less than the limit of detection after 45 min of treatment. The PEF process was also tested for real surface water contaminated by ATZ: i) with and without addition of iron; ii) without pH adjustment (pH similar to 6.7) and with pH adjustment (pH similar to 3.1). In spite of the presence of radical scavenger and iron complexation the PEF process was more effective to remove ATZ from real surface water when the pH value was adjusted near to 3.0. The ATZ removal was 96.0% with 0.01 mM of iron (k(app) = 0.13 min(-1)) and 100% with 0.1 mM of iron (k(app) = 0.17 min(-1)). (C) 2017 Elsevier Ltd. All rights reserved.