复合表面活性剂（SDS/Tw-80）对长链烷烃的增溶和柴油污染土壤的洗脱作用

表面活性剂能够快速高效处理石油污染土壤,但由于所选用表面活性剂的类型和配比、土壤性质、污染物种类的差异,洗脱效果和作用原理不尽相同。通过研究复合表面活性剂SDS/Tw-80对石油烷烃的表观增溶和从受试土壤中的洗脱过程,探讨和阐释影响洗脱过程的各种因素。结果表明,复合表面活性剂对污染土壤中的石油烷烃洗脱效果较单一表面活性剂更好,且随复合表面活性剂SDS/Tw-80中的组分配合比例的增大而显著提高,同时能够降低胶束的成束浓度要求,扩大目标物在单位胶束内的容纳量,促使各目标长链烷烃进入胶束内部的趋势加大。复合表面活性剂的适用不仅能够改善胶束构成,且组分间表现出显著的协同作用,从而使在保证较高洗脱效率的同时能够大幅降低试剂用量,有效地克服土壤的吸附作用,把对土壤性状的影响降低,对土壤质量的恢复具有积极意义。

Compound Surfactants（SDS/Tw-80）Effects on the Solubilization and Washing of Long-chain Alkyl from the Diesel Oil Contaminated Soil

Oil contaminated soil can be treated by composite surfactant eluent effectively.Different surfactants,mixing ratio,soil texture and contaminants have different removal mechanism and efficiency.In this research,a composite surfactant SDS/Tw-80 was used to wash the contaminated soil to investigate its removal mechanism from the soil and the factors influencing the efficiency.The results showed that com-posite surfactant was better than individual components in soil washing.A higher SDS/Tw-80 ratio significantly increased the apparent solu-bility of contaminants,lowered the micelle-forming concentration,increased the capacityof micelle to hold contaminants,and increased the chance for the long-chain alkanes to enter the micelle.Composite surfactant could improve micelles composition and showed markedly syn-ergistic effect.For these reasons,it could reduce surfactant dosage to a great extent while remaining high elution efficiency.Using composite surfactant is an effective solution to overcomeing the sorption of contaminant by soils while minimizing the impact on soil quality.