Sorption/desorption behavior of triclosan in sediment-water-rhamnolipid systems: Effects of pH, ionic strength, and DOM
Sorption/desorption behavior of triclosan in sediment-water-rhamnolipid systems: Effects of pH, ionic strength, and DOM
复制标题
三氯生在沉积物-水-鼠李糖脂系统中的吸附/解吸行为：pH、离子强度和 DOM 的影响
DOI：
10.1016/j.jhazmat.2015.04.078
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发表时间：
2015-10-30
影响因子：
13.6
通讯作者：
Cheng, Jianhua
中科院分区：
文献类型：
--
作者：
Wu, Wenjin;Hu, Yongyou;Cheng, Jianhua
通过批量控制实验，系统研究了 pH、离子强度和 DOM 对沉积物-水-鼠李糖脂体系中三氯生 (TCS) 吸附和解吸的影响。结果表明，鼠李糖脂对TCS的增溶作用在酸性pH范围内高于在碱性pH范围内，且在离子强度为5 x 10(-2) M时最强。随着pH的增加，鼠李糖脂对沉积物的吸附减弱，而结果与离子强度相反。此外，随着溶液pH值的增加，TCS的表观分配系数(K-d*从73.35 L/kg降低到32.30 L/kg，因为不同的pH值对RI在沉积物上的吸附和TCS的电离程度有显着影响。鼠李糖脂质在中等离子强度(5 x 10(-2) M)下表现出最大的TCS到水相的分配能力，K-d*为17.26 L/kg。进一步的结果还表明水相中腐殖酸的存在可以增加 TCS 从受污染沉积物中的解吸，在含有鼠李糖脂和 DOM 的系统中，解吸增强程度比在单一系统中高得多。这些发现为增强 TCS 从沉积物到水中的迁移提供了有意义的信息 (C) 2015 Elsevier B.V. 保留所有权利。
Effects of pH, ionic strength and DOM on the sorption and desorption of triclosan (TCS) in sediment-water-rhamnolipid systems were systematically investigated through controlled batch experiments. Results showed that solubilization enhancement of TCS by rhamnolipid was higher in acid pH range than in alkaline pH range and was the highest at the ionic strength of 5 x 10(-2) M. Sorption of rhamnolipid onto sediment decreased with the increase of pH while the result was contrary to ionic strength. Moreover, the apparent distribution coefficients of TCS (K-d* decreased from 73.35 to 32.30 L/kg with an increase of solution pH, as varying pH had significant influence on sorption of RI onto sediment and degree of ionization of TCS. Rhamno lipid presented the largest distribution capacity of TCS into the aqueous phase at moderate ionic strength (5 x 10(-2) M) with the K-d* of 17.26 L/kg. Further results also indicated that the presence of humic acid in aqueous phase could increase the desorption of TCS from contaminated sediment. The desorption enhancement was much higher in the system containing both rhamnolipid and DOM than in the single system. These findings provide meaningful information for enhanced migration of TCS from sediment to water by rhamnolipid. (C) 2015 Elsevier B.V. All rights reserved.