表面活性剂复配体系修复芘污染土壤实验

以芘污染土壤为对象，利用阴离子表面活性剂鼠李糖脂和非离子表面活性剂皂素进行复配实验，得出最佳复配比并对污染土壤进行修复处理；其次，研究表面活性剂浓度、pH及CaCl₂、MgCl₂、KCl三种离子浓度、洗脱液的回收次数等单因素对洗脱效果的影响；然后利用响应曲面分析，确定影响洗脱效果的主效应因素及其交互作用强度；最后用Box-Behnken模型优化复配体系处理芘污染土壤的实验条件。结果表明：①当复配比为0.2时，鼠李糖脂-皂素混合溶液的表面张力最低，对芘的协同增溶效果最好；②复配体系处理芘污染土壤的单因素实验中，复配药剂浓度、pH、Mg²⁺浓度分别达到1800mg/L、8、0.1mmol/L时，洗脱效率最高；③环境因素对芘去除效果的影响从大到小依次为pH>表面活性剂浓度>Mg²⁺浓度，表面活性剂浓度与pH对芘的洗脱产生较大的交互影响作用，而pH与盐浓度的交互作用最微弱；④Box-Behnken模型优化后得出最佳组合是混合表面活性剂浓度为1900mg/L、pH为5、Mg²⁺浓度为0.2mmol/L，得到的洗脱效率为89.25%。

Remediation of pyrene-contaminated soil using mixed surfactants solution

The remediation potential of pyrene contaminated soil by anionic-nonionic mixed surfactants were texted in this study. Firstly, the best ratio of mixed surfactants with rhamnolipid and saponin was obtained through measured surface tension. Secondly, the influence of single factors such as surfactant concentration, pH, CaCl₂, MgCl₂, KCl ionic strength and the number of recovery of eluent on the elution effect were studied by complete randomalized design. Then, response surface methodology (RSM) was used to screen out the main influencing factors affected the elution repair effect and texted their interaction intensity. Finally, the optimal elution condition of pyrene contaminated soil by mixed surfactants was established by Box-Behnken design. The main results of this study were shown as follows: ①mixed surfactants with rhamnolipid and saponin can synergistically reduce surface tension of solution and enhance the elution of pyrene in contaminated soils, mass ratio of 0.2 mixed surfactants with hamnolipid-saponin had the lowest surface tension and the best synergistic solubilization effect on pyrene. ②In the single-factor experiment of the mixed surfactants on the pyrene contaminated soil, the highest elution efficiency was got at mixed surfactants concentration, pH and Mg²⁺ reached 1800mg/L, 8 and 0.1mmol/L, respectively. ③According to the response surface analysis, the influence of environmental factors on the removal effect of pyrene was in order of pH>surfactant concentration>Mg²⁺ concentration. The mixed surfactants concentration and pH had the best interaction effect on the elution of pyrene, while the interaction between pH and salinity was the weakest. ④After the optimization of the Box-Behnken design, the optimal experimental conditions with the mixed surfactants concentration of 1900mg/L, pH of 5 and Mg²⁺concentration of 0.2mmol/L were determined, and the removal efficiency of pyrene reached 89.25%.