溶剂萃取是分离地下水强化抽出处理液中表面活性剂和污染物的有效方法。以Tween80为表面活性剂,苯和硝基苯为污染物,正己烷、正癸烷和正十六烷为萃取剂,通过批次实验研究Tween80质量浓度、污染物和萃取剂性质对分离效果的影响规律。研究结果表明:正己烷对Tween80和苯的分离效果较好,且随着Tween80质量浓度的升高,苯的去除率没有显著变化,但在Tween80质量浓度超过25mg/L后,苯去除率逐渐降低:Tween80损失率没有随其质量浓度的增大呈现规律性的变化;正己烷对苯与Tween80的分离效果较硝基苯好,且随着笨和硝基苯浓度的升高,污染物的分离去除率增大,而Tween80的损失率先减少后增大;萃取剂EACN(等效烷烃碳数)对苯和Tween80的分离有较大影响,随着苯质量浓度的增大,苯去除率均有所升高,但升高的程度有所不同,升高程度由大至小为正己烷、正癸烷和正十六烷,而Tween80损失率顺序从大至小为正十六烷、正癸烷和正己烷。
Solvent extraction is an efficient method, which separates surfactants and pollutants in surfactant enhanced aquifer remediation (SEAR). The effects of Tween 80 mass concentration, contaminations and extractions natures on separation effect were investigated with Tween 80 as surfactant, benzene and nitrobenzene as the target contaminants, n-hexane, n-decane and n-hexadecane as extracting agents through batch experiments. The results show that the effect of separating benzene from aqueous Tween 80 solutions is preferable for n-hexane. And with the increase of Tween 80 mass concentration, benzene removal seldom changes. However, benzene removal declines gradually when the mass concentration of Tween 80 is above 25 mg/L. Tween 80 loss does not change regularly as Tween 80 concentration increase. For n-hexane, the effect of separating benzene and Tween 80 is better than nitrobenzene and Tween 80. Both benzene and nitrobenzene removal increase with the increase of contaminants mass concentration, while Tween 80 loss decreases firstly, and then increases. Solvent EACN has significant impact on the separation of benzene from aqueous Tween 80 solutions. Benzene removal increases with the increase of the benzene concentration, but the degrees of these increments are quite different, and can be shown in the following order from large to small rate: n-hexane, n-decane and n-hexadecane. However, the order of Tween 80 losses from large to small rate is n-hexadecane, n-decane and n-hexane.