Zeng Qing-ru, Tang Hong-xiao, Liao Bo-han, Zhong Toufen, Tang Can
State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China.
Water Res. 2006 Apr;40(7):1351-8. doi: 10.1016/j.watres.2006.01.036. Epub 2006 Mar 15.
The removal of hydrophobic organic compounds (HOCs) from soils and sediments by water flushing is often constrained by sorption interactions. The development of improved methods for remediation of contaminated soils has emerged as a significant environmental priority. Increasing HOCs desorption and mobility in soil using surfactants is considered to be one of the most suitable on-site techniques for soil remediation. A major concern regarding the use of surfactants for environmental restoration is the potential loss to the environment of large amounts of surfactant through sorption of nonionic types. A study was conducted to investigate whether surfactants and cyclodextrins can be used to enhance the transport of methyl-parathion in a contaminated soil. At aqueous concentrations of surfactants tested, the proportion of each surfactant sorbed to the soil increased with increasing surfactant concentrations. The maximal adsorbed mass is about 5,130 and 14,200 microg/g for Brij 35 and Tween 80, respectively. In the case of nonionic surfactants, sorption attenuates surfactant effectiveness by increasing the organic carbon content of the soil matrix and retarding transport of methyl-parathion through batch and soil column experiments. However, in contrast with the surfactants, hydroxypropyl-beta-cyclodextrin (HPCD) does not interact with the soil tested. The nonreactive nature of cyclodextrins, combined with its large affinity for HOCs suggests that it should have an advantage versus adsorbing surfactants for decreasing HOC distribution coefficients in subsurface systems.
通过水洗从土壤和沉积物中去除疏水性有机化合物（HOCs）通常受到吸附作用的限制。开发改进的污染土壤修复方法已成为一项重要的环境优先事项。使用表面活性剂增加HOCs在土壤中的解吸和迁移率被认为是最适合土壤修复的现场技术之一。使用表面活性剂进行环境修复的一个主要问题是大量非离子型表面活性剂可能通过吸附而流失到环境中。开展了一项研究，以调查表面活性剂和环糊精是否可用于增强甲基对硫磷在污染土壤中的迁移。在所测试的表面活性剂的水相浓度下，每种表面活性剂吸附到土壤中的比例随表面活性剂浓度的增加而增加。对于Brij 35和吐温80，最大吸附量分别约为5130和14200微克/克。在非离子表面活性剂的情况下，通过批量和土柱实验，吸附通过增加土壤基质的有机碳含量和阻碍甲基对硫磷的迁移来削弱表面活性剂的有效性。然而，与表面活性剂不同，羟丙基-β-环糊精（HPCD）与所测试的土壤不发生相互作用。环糊精的非反应性，加上其对HOCs的高亲和力，表明在降低地下系统中HOC分配系数方面，它相对于吸附性表面活性剂应具有优势。
