School of Environment Science and Resources, Shanxi University, Taiyuan, Shanxi, 030006, China.
Institute of Resources and Environment Engineering, Shanxi University, Taiyuan, Shanxi, 030006, China.
Environ Sci Pollut Res Int. 2018 Jan;25(1):18-26. doi: 10.1007/s11356-016-7711-0. Epub 2016 Oct 3.
Surfactant-enhanced remediation is less applicable for the treatment of dichlorobenzene (DCB)-contaminated soil. In this study, water solubility enhancements of o-dichlorobenzene (o-DCB) and p-dichlorobenzene (p-DCB) by micellar solutions of biosurfactants (saponin, alkyl polyglycoside) and chemically synthetic surfactant (Tween 80) were measured and compared. Solubilities of o,p-DCB in water were greatly enhanced in a linear fashion by each of Tween 80, saponin, and alkyl polyglycoside. Solubility enhancement efficiencies of surfactants followed the order of Tween 80 > saponin > alkyl polyglycoside. However, the ex situ soil washing experiment demonstrated the opposite result. The removal efficiency of o,p-DCB by biosurfactant saponin and alkyl polyglycoside was higher than that of chemically synthetic surfactant Tween 80 in contaminated soil. This difference may be due to the different adsorption behaviors of the surfactants onto soil. In addition, elution kinetics for o,p-DCB were relatively fast, with apparent elution equilibrium reached within 360 min, and can be described by a pseudo first-order kinetic equation. The elution process of o,p-DCB in soil-aqueous systems obeyed four-parameter biphasic first-order kinetic model including rapid and slow phases. The results confirmed potential application of saponin and alkyl polyglycoside in elution solution for enhanced remediation of DCB-contaminated soil.
表面活性剂增强修复对于处理二氯苯 (DCB) 污染土壤的应用较少。本研究测量并比较了生物表面活性剂（皂苷、烷基糖苷）和化学合成表面活性剂（吐温 80）胶束溶液对邻二氯苯 (o-DCB) 和对二氯苯 (p-DCB) 的增溶作用。o,p-DCB 在水中的溶解度通过 Tween 80、皂苷和烷基糖苷线性大幅增加。表面活性剂的增溶效率顺序为 Tween 80＞皂苷＞烷基糖苷。然而，原位土壤洗涤实验得到了相反的结果。生物表面活性剂皂苷和烷基糖苷对 o,p-DCB 的去除效率高于化学合成表面活性剂吐温 80 在污染土壤中的去除效率。这种差异可能是由于表面活性剂在土壤上的不同吸附行为所致。此外，o,p-DCB 的洗脱动力学相对较快，表观洗脱平衡在 360 分钟内达到，并可以用拟一级动力学方程来描述。o,p-DCB 在土壤-水体系中的洗脱过程遵循包括快速和缓慢相的四参数双相一级动力学模型。结果证实了皂苷和烷基糖苷在洗脱液中用于增强修复 DCB 污染土壤的潜在应用。
