应用表面活性剂-生物柴油微乳液去除污染土壤中多环芳烃

针对修复焦化厂高浓度多环芳烃污染土壤高成本的现实,采用以非食用性植物油、生物柴油、表面活性剂及其乳化合成的微乳液为淋洗剂,比较不同淋洗剂的淋洗效果。结果表明乳化合成的微乳液对焦化厂土壤中多环芳烃的总去除率高于单独使用表面活性剂为淋洗剂对土壤中多环芳烃的总去除率,说明生物柴油及植物油与表面活性剂乳化形成的微乳液对原污染土壤中的多环芳烃具有显著的增溶作用。1%TW-80和2.5%TW-80对土壤中多环芳烃总去除率分别为11%和14%;以2.5%TW-80为原料乳化合成的微乳液的淋洗去除率较以1%TW-80为原料乳化合成的微乳液高,总去除率分别为15%～30%和11%～18%;以生物柴油为原料乳化合成的微乳液的淋洗去除率较以植物油为原料乳化合成的微乳液高,分别为17%～30%和15%～23%,且对多环芳烃的去除率与其辛醇水分配系数(logKow)呈线性相关关系。

Application of microemulsion synthesized by surfactant and biodiesel to remove polycyclic aromatic hydrocarbons from contaminated soil

It has been an issue that remediation of soils with high concentrations of PAHs will spend too much.Four kinds of solutions,non-edible plant oil,biodiesel,surfactants and microemulsion which was synthesized by surfactant and biodiesel or vegetable oil,were selected as the washing agents to study the PAH removal.Results showed that microemulsion got a higher total PAH removal than surfactact addition alone,which indicated that biodiesel and non-edible plant oil could enhance desorption of PAHs from MGP soil in the presence of surfactants.2.5% tween 80 solution resulted in more obvious enhancement of PAH desorption from the contaminated soil compared to 1% tween 80,the PAH removals were 14% and 11% individually.Microemulsion from 2.5% tween 80 induced a higher PAH removal than microemulsion from 1% tween 80,PAH removal ranged from 15% and 11% to 30% and 18%,separately.Addition bidiesel to surfactant obtained higher PAH removals compared to vegetable oil addition,the PAH removals were ranged from 17% and 15% to 30% and 23%,respectively,and a good correlation was found between removals of individual PAHs and their logKow.