复合醇原位微乳液增溶含水层四氯乙烯性能研究

The performance of tetrachloroethylene solubilization in the aquifer by in-situ microemulsion of composite alcohols

利用绿色非离子表面活性剂月桂基葡糖苷(APG1214)制备了适用于修复地下水四氯乙烯(PCE)污染的复合醇原位微乳液,探究了环境因素对微乳液成相能力和增溶性能的影响,并模拟含水层考察其原位淋洗PCE性能.结果表明,1.0wt.%APG1214-5.6wt.%异丁醇/正丙醇(1:1)-0.8wt.%NaCl微乳液具有适宜的醇宽,对PCE增溶浓度约为550g/L,在减轻含水层介质吸附、控制污染物垂向迁移、避免二次污染等方面表现出良好性能.环境因素对微乳液成相稳定性影响不显著,在强酸性和低温环境下增溶性能减弱.原位淋洗过程通过增流和增溶作用去除介质中的PCE,淋洗后PCE的去除率达到99.4%.总之,该微乳液具有增溶能力强、醇宽大、表面活性剂用量低的优点,且环境适用范围广,原位淋洗PCE去除率高,适用于修复地下水PCE污染.

In this study,a green nonionic surfactant,Lauryl glucoside(APG1214),was used to prepare an in-situ microemulsion of composite alcohols suitable for the remediation of tetrachloroethylene(PCE)contamination in groundwater.The effects of environmental factors on the phase behavior and solubilization of microemulsion were investigated.Besides,by simulating the aquifer,the performance of microemulsion in-situ leaching PCE was investigated.The results showed that 1.0wt.%APG1214-5.6 wt.%n-propanol/isobutanol(1:1)-0.8wt.%NaCl microemulsion had suitable alcohol width,and the solubility of PCE was about 550g/L.It showed good performance in reducing the adsorption of aquifer media,controlling vertical migration of pollutants,and preventing secondary pollution.The phase stability of the microemulsion was not significantly affected by environmental factors,but its solubilization was reduced in strong acid and low-temperature environments.Moreover,the in-situ leaching process removed PCE in the media by solubilization and mobilization,and the removal efficiency of PCE reached 99.4%after leaching.In all,the microemulsion has the advantages of strong solubilization ability,wide alcohol width,low surfactant dosage,wide environmental application range,and high removal efficiency of PCE after in-situ leaching,which makes it suitable for remediating PCE pollution in groundwater.