Department of Earth and Environmental Sciences, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
Department of Earth and Environmental Sciences, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
Sci Total Environ. 2019 Nov 15;691:165-177. doi: 10.1016/j.scitotenv.2019.06.450. Epub 2019 Jun 28.
Emerging contaminants are widely detected and persistent in environmental waters. Advanced oxidation processes are among the most effective methods for removing emerging contaminants from water; however, high energy consumption greatly increases the operating costs and limits large-scale applications. In this study, a passive treatment system consisting of four columns packed with mixtures of silica sand, zero-valent iron (ZVI), biochar (BC), and a mixture of (ZVI + BC) were evaluated for simultaneous removal of eight pharmaceuticals, four artificial sweeteners, and two perfluoroalkyl substances (PFASs) from water. Overall, the passive treatment system was more effective for removing target pharmaceuticals (almost complete removal) than artificial sweeteners and PFASs (partial removal). Columns ZVI, BC, and (ZVI + BC) exhibited similarly effective removal (>97%) of target pharmaceuticals, including carbamazepine, caffeine, sulfamethoxazole, 3,4-methylenedioxyamphetamine, 3,4-methylenedioxymethamphetamine, ibuprofen, gemfibrozil, and naproxen, from 9 to <0.25 μg L; pharmaceuticals were more rapidly removed by Columns ZVI and (ZVI + BC) than Column BC, except for ibuprofen. Column ZVI was more effective for removing artificial sweeteners acesulfame-K and sucralose than Columns BC and (ZVI + BC); however, BC exhibited relatively greater removal of saccharin than ZVI and (ZVI + BC). Acesulfame-K and saccharin (110 μg L) were partially removed in the treatment columns. Cyclamate was not removed in any of the columns. However, >76% of input sucralose (110 μg L) was removed in the three treatment columns. Reactive medium BC alone was more effective for removing target PFASs than ZVI and (ZVI + BC). Input perfluorooctanoic acid (PFOA) (45 μg L) was partially removed in the columns containing BC but not ZVI alone. Between 10 and 80% of input perfluorooctane sulfonic acid (PFOS) (24 ̶ 90 μg L) was removed in Column ZVI; greater removals (57 ̶ 99%) were observed in Columns BC and (ZVI + BC).
新兴污染物广泛存在于环境水中，并且具有持久性。高级氧化工艺是去除水中新兴污染物最有效的方法之一；然而，高能耗大大增加了运营成本，限制了其大规模应用。在这项研究中，评估了由四个柱体组成的被动处理系统，这些柱体填充有硅砂、零价铁（ZVI）、生物炭（BC）和（ZVI+BC）混合物，用于从水中同时去除八种药物、四种人工甜味剂和两种全氟烷基物质（PFASs）。总体而言，被动处理系统对目标药物（几乎完全去除）的去除效果优于人工甜味剂和 PFASs（部分去除）。ZVI、BC 和（ZVI+BC）柱对包括卡马西平、咖啡因、磺胺甲恶唑、3,4-亚甲二氧基苯丙胺、3,4-亚甲二氧基甲基苯丙胺、布洛芬、吉非贝齐和萘普生在内的目标药物的去除效果相似（>97%），这些药物的去除浓度从9 至 <0.25μg/L；除布洛芬外，ZVI 和（ZVI+BC）柱对药物的去除速度明显快于 BC 柱。ZVI 柱对乙酰磺胺酸钾和三氯蔗糖的去除效果优于 BC 和（ZVI+BC）柱；然而，BC 对糖精的去除效果相对大于 ZVI 和（ZVI+BC）。乙酰磺胺酸钾和糖精（110μg/L）在处理柱中部分被去除。环丙氨酸在任何柱中均未被去除。然而，输入三氯蔗糖（110μg/L）的>76%在三个处理柱中被去除。单独的反应性介质 BC 比 ZVI 和（ZVI+BC）更有效地去除目标 PFASs。含有 BC 的柱体中部分去除了输入的全氟辛酸（PFOA）（45μg/L），但 ZVI 柱体中未去除。输入的全氟辛烷磺酸（PFOS）（24 ̶ 90μg/L）中有 10%至 80%在 ZVI 柱中被去除；在 BC 和（ZVI+BC）柱中观察到更大的去除率（57 ̶ 99%）。
