表面活性剂与柠檬酸联合洗涤高黏性土壤中的重金属

以一水合柠檬酸(CA)为洗涤剂,分别采用吐温80(TW80)、十二烷基磺酸钠(SDS)、β-环糊精(BCD)和腐植酸(HA)4种表面活性剂与CA联合洗涤高黏性土壤中的重金属,考察表面活性剂与CA的联合洗脱效果。实验结果表明:添加4种表面活性剂均可提高CA对Cu、Zn和Pb的去除率;处理时无需调节体系pH;在表面活性剂与CA的混合液与土壤的液固比为10∶1(mL/g)的条件下,采用一次洗涤即可。经4种表面活性剂与CA联合洗涤后,土壤中Cu、Zn和Pb的离子交换态、碳酸盐结合态和铁锰氧化结合态的占比均下降,而硫化物及有机结合态和残渣态的占比有所提升。

Heavy metals removal from high viscosity soil by washing using surfactant and citric acid

Citric acid monohydrate （CA）was used as washing agent and combined with Tween 80 （TW80）,Sodium laurylsulfonate （SDS）,β-cyclodextrin crystalline （BCD）and humic acid （HA）respectively,to remove heavy metals from high viscosity soil by washing. The combination washing effects of the 4 surfactants and CA were studied. The experimental results show that：The removal rate of Cu,Zn and Pb can be promoted by adding each surfactant along;The system pH is no need to adjust;When the conditions of liquid-solid ratio of surfactant-CA mixture of to soil is 10:1 （mL/g）,one-time washing is enough. After the combination washing,the proportion of Cu,Zn and Pb with ion exchange state,carbonates bound state and Fe-Mn oxides bound state in soil are decreased,while that with sulfide state,organic bound state and residue state are increased.