Aquatic photolysis of hydroxylated polybromodiphenyl ethers under direct UVirradiation: a case study of 2 '-HO-BDE-68
Aquatic photolysis of hydroxylated polybromodiphenyl ethers under direct UVirradiation: a case study of 2 '-HO-BDE-68
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DOI：
10.1007/s11356-017-8726-x
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发表时间：
2017
影响因子：
5.8
通讯作者：
Xu G
中科院分区：
文献类型：
--
作者：
Xu Bentuo;Wu Minghong;Pan Chenyuan;Sun Yan;Yuan Debao;Tang Liang;Xu Gang;Xu Gang;Xu G;Xu G
羟基化多卤代二苯醚（HO-PXDE）作为新出现的水生污染物引起了科学界的极大兴趣。然而，很少对这种特殊污染物的处置方法进行全面评估。以2′-HO-2，3′，4，5′-四溴二苯醚（2′-HO-BDE-68）为例，研究了HO-PXDE的紫外光降解特性。结果表明，紫外光对2′-HO-BDE-68的降解率上级优于可见光和电子束。在低浓度下，HO-BDE的降解率随初始浓度的降低没有明显提高。在碱性溶液中降解效率也较好。在UV/H_2O_2体系中，H_2O_2提供的羟基自由基可提高降解效率。确定了2′-HO-BDE-68的主要光解产物，并提出了可能的光解途径。1，3，8-三溴二苯并-对-二恶英是紫外光降解的产物之一，这表明在紫外光降解过程中还必须考虑二次污染。
Hydroxylated polyhalodiphenyl ethers (HO-PXDEs) have attracted considerable scientific interest as examples of emerging aquatic pollutants. However, a comprehensive assessment of disposal methods for this particular pollutant was seldom investigated. This study examined the UV light degradation of HO-PXDEs, using 2′-HO-2, 3′, 4, 5′-tetrabromodiphenyl ether (2′-HO-BDE-68) as a case study. The results showed that UV light was superior to visible light and electron beam irradiation for producing a high degradation rate of 2′-HO-BDE-68. At low concentrations of HO-BDE, the degradation rate was not obviously improved with decreasing initial concentration. The degradation efficiency was also found to be better in alkaline solutions. In a UV/H2O2system, the hydroxyl radical provided by H2O2was shown to enhance the degradation efficiency. The main photolysis products of 2′-HO-BDE-68 were identified, and the possible photodegradation pathways were proposed. 1, 3, 8-Tribromodibenzo-p-dioxin was one of the photoproducts, which indicates that secondary pollution must also be considered with the UV photolysis process.