School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, PR China; Shanghai Environmental Monitoring Center, Shanghai, 200235, PR China.
School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, PR China.
Chemosphere. 2018 Jan;190:184-190. doi: 10.1016/j.chemosphere.2017.09.133. Epub 2017 Oct 3.
With the development of psychiatric disorder in the current society, abuse of antidepressant drug fluoxetine (FLX) has made such compound an emerging contaminant in natural waters, and causes endocrine systems disturbance on some aquatic species. Herein, an efficient advanced oxidation process (AOP), electron beam irradiation was carried out to investigate the decomposition characteristics of such novel environmental pollutant, including the effects of initial concentration, pH, radical scavengers and anions. The results showed that FLX degradation followed pseudo-first-order kinetics. The degradation rate and dose constant decreased with increasing initial FLX concentration; and G-values elevated with the increase of initial concentration but reduced with increase of absorbed dose. Acidic condition was more conducive to FLX destruction than neutral and alkaline. The radical scavenger experiments indicated OH was the main reactive species for the decomposition of FLX, while the reductive species e and H played an adjuvant role. The presence of anions slightly decreased or even no impact on FLX degradation rate. Various water matrices influenced degradation processes of FLX. Experimental results suggested radiolytic degradation showed the best performance in pure water rather than natural water no matter with filtration or not. Moreover, with the occurrence of defluorination and dealkylation during degradation process, some organic and inorganic intermediates were detected, and the possible degradation mechanisms and pathways of FLX were proposed.
随着当前社会精神障碍的发展，抗抑郁药氟西汀（FLX）的滥用使得这种化合物成为天然水中的一种新兴污染物，并对一些水生物种的内分泌系统造成干扰。在此，采用电子束辐照这一高效的高级氧化工艺（AOP）来研究这种新型环境污染物的分解特性，包括初始浓度、pH 值、自由基清除剂和阴离子的影响。结果表明，FLX 的降解遵循准一级动力学。降解速率和剂量常数随初始 FLX 浓度的增加而降低；G 值随初始浓度的增加而升高，但随吸收剂量的增加而降低。酸性条件比中性和碱性条件更有利于 FLX 的破坏。自由基清除实验表明，OH 是 FLX 分解的主要反应性物质，而还原物质 e 和 H 则起辅助作用。阴离子的存在对 FLX 降解速率的影响较小，甚至没有影响。各种水基质会影响 FLX 的降解过程。实验结果表明，无论是否经过过滤，辐解在纯水中的表现都优于天然水。此外，在降解过程中发生脱氟和脱烷基化，检测到一些有机和无机中间体，并提出了 FLX 的可能降解机制和途径。
