Sino-Forest Applied Research Centre for Pearl River Delta Environment, and Department of Biology, Hong Kong Baptist University, Hong Kong SAR, China.
Environ Sci Technol. 2012 Nov 6;46(21):12062-8. doi: 10.1021/es302832z. Epub 2012 Oct 8.
The effect of oil-swollen micelles formed with nonionic surfactant polyoxyethylene sorbitan monooleate (Tween 80), cosurfactant 1-pentanol, and linseed oil on the solubilization and desorption of organochlorine pesticides (OCPs) including DDT and γ-HCH from both loam soil and clay soil were investigated. Results showed that the solubilizing capacities of oil-swollen micelles were dependent on the critical micelle concentration (CMC) of Tween 80. Once the concentrations of oil-swollen micelles exceeded the CMC of Tween 80, the oil-swollen micelles exhibited much higher solubilizing capacity than empty Tween 80 micelles for the two OCPs. Desorption tests revealed that oil-swollen micelles could successfully enhance desorption of OCPs from both loam soil and clay soil. However, compared with the efficiencies achieved by empty Tween 80 micelles, oil-swollen micelles exhibited their superiority to desorb OCPs only in loam soil-water system while was less effective in clay soil-water system. Distribution of Tween 80, 1-pentanol and linseed oil in soil-water system revealed that the difference in the sorption behavior of linseed oil onto the two soils is responsible for the different effects of oil-swollen micelles on the desorption of OCPs in loam soil and clay soil systems. Therefore, oil-swollen micelles formed with nonionic surfactant Tween 80 are better candidates over empty micelle counterparts to desorb OCPs from soil with relatively lower sorption capacity for oil fraction, which may consequently enhance the availability of OCPs in soil environment during remediation processes of contaminated soil.
本文研究了由非离子表面活性剂聚氧乙烯山梨醇单油酸酯（吐温 80）、助表面活性剂 1-戊醇和亚麻籽油形成的油增溶胶束对滴滴涕和γ-六氯环己烷等有机氯农药（OCPs）在壤土和粘土壤中的增溶和解吸的影响。结果表明，油增溶胶束的增溶能力取决于吐温 80 的临界胶束浓度（CMC）。一旦油增溶胶束的浓度超过吐温 80 的 CMC，油增溶胶束对两种 OCPs 的增溶能力就远远高于空吐温 80 胶束。解吸实验表明，油增溶胶束可以成功增强 OCPs 从壤土和粘土壤中的解吸。然而，与空吐温 80 胶束的效率相比，油增溶胶束仅在壤土-水体系中表现出优于空吐温 80 胶束的解吸 OCPs 的效果，而在粘土壤-水体系中效果较差。吐温 80、1-戊醇和亚麻籽油在水土体系中的分布表明，亚麻籽油在两种土壤上的吸附行为的差异是导致油增溶胶束对壤土和粘土壤体系中 OCPs 解吸效果不同的原因。因此，对于油分吸附能力相对较低的土壤，由非离子表面活性剂吐温 80 形成的油增溶胶束是比空胶束更合适的 OCPs 解吸剂，这可能会增强污染土壤修复过程中土壤环境中 OCPs 的有效性。
