Irreversible sorption of pentachlorophenol to sediments: experimental observations
Irreversible sorption of pentachlorophenol to sediments: experimental observations
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DOI：
10.1016/s0160-4120(03)00145-4
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发表时间：
2004-03-01
影响因子：
11.8
通讯作者：
Shen, MW
中科院分区：
文献类型：
--
作者：
Chen, YX;Chen, HL;Shen, MW
利用平衡吸附实验和多循环吸附和解吸实验研究了五氯苯酚（PCP）在五种沉积物中的分配行为。平衡吸附实验结果表明，五氯苯酚在五种沉积物上的等温线呈线性，分配系数（K-d）与沉积物的有机碳含量成正比。五种沉积物的平均有机碳含量归一化分配系数(logK(oc))为2.83+/-1.48。在多次吸附和解吸实验中，发现五种沉积物表现出统计上显着的吸附-解吸滞后现象，并且滞后指数（HI）在很宽的范围内变化（0.72 - 11.82）。 HI值与沉积物中脂质占总有机质的百分比之间的相关性表明，脂质是影响滞后现象的主要部分，即脂质百分比越高，HI值越大。滞后现象主要是由于五氯苯酚对脂质的不可逆吸附引起的，包括脂质的截留，导致沉积物解吸速率缓慢。由于吸附和解吸存在滞后现象，PCP的生态毒性将低于预期。 (C) 2003 年，爱思唯尔有限公司出版。
The partitioning behavior of pentachlorophenol (PCP) in five sediments was studied using equilibrium sorption experiments and multiple cycles of sorption and desorption experiments. The results of the equilibrium sorption experiments showed that the isotherms of PCP on five sediments were linear and the partitioning coefficients (K-d) were proportional to the organic carbon content of the sediments. The average organic carbon content normalized partitioning coefficient (logK(oc)) of five sediments was 2.83 +/- 1.48. In multiple cycles of sorption and desorption experiments, the five sediments were found to exhibit statistically significant sorption-desorption hysteresis, and the hysteresis indices (HI) varied over a wide range (0.72 - 11.82). Correlations between the HI value and the percentage of lipid in the total organic matter in the sediment indicated that lipid was the main fraction to affect the hysteresis phenomenon, i.e., the higher the lipid percentage the greater the HI value. The hysteresis phenomenon was mostly caused by irreversible sorption of PCP on lipids, including entrapment by lipids, which induced the slow desorption rate from the sediment. Because of hysteresis in the sorption and desorption, the PCP ecological toxicity would be lower than expected. (C) 2003 Published by Elsevier Ltd.