鼠李糖脂协助下的土壤中镉电动修复

实验研究了重金属Cd在生物表面活性剂鼠李糖脂协助下的电动修复过程,通过不同方式、不同浓度、不同酸碱度的鼠李糖脂溶液的添加与空白处理对比,探讨了鼠李糖脂协助下电动修复过程中的Cd在土壤介质中的迁移转化和机理,分析了鼠李糖脂溶液作为电动修复添加剂的可行性。结果表明,中等浓度酸性的鼠李糖脂溶液(pH=4.78,浓度为0.5、1和2 g/L)能对土壤中的重金属Cd进行有效的富集,富集量均在初始值的4倍以上,且其可交换态比重均大于42.07%,非常有利于土壤进行二次修复。此外,以pH=4.78,浓度为0.5 g/L的鼠李糖脂溶液作为预处理剂的Ex-08中的重金属Cd并未出现富集现象,但其对重金属的Cd的总去除效率达到了49.27%。表明利用鼠李糖脂溶液作为电动修复添加剂进行土壤重金属修复是可行的。

Rhamnoilpid-assisted electrokinetic remediation of cadmium contaminated soil

The effect of rhamnoilpid,a biosurfactant,on electrokinetic remediation of cadmium(Cd)contaminated soil was investigated in this study.A range of laboratory experiments were conducted to determine characteristics and mechanisms of electrokinetic remediation of the contaminated soil under different conditions.The feasibility of using rhamnolipid as an additive was discussed as well.The results indicated that the rhamnolipid at pH=4.78 and different concentrations,in the range of 0.5~2 g/L,can be used as a cathode additive to improve the effect of electrokinetic remediation of Cd-contaminated soils through controlling soil pH values,increasing Cd accumulations(more than 4 times),increasing exchangeable Cd,and favoring secondary remediation.In additon,when the rhamnolipid(pH=4.78,0.5 g/L)was saturated with soil,there was no accumulation of Cd found in the soil,and 49.27% of Cd was removed.It is feasible to conduct electrokinetic remediation by usig rhamnolipid as the cathode additives.