表面活性剂对土壤中多环芳烃解吸行为的影响

Desorption of Polycyclic Aromatic Hydrocarbons from Soil in Presence of Surfactants

研究了4种表面活性剂对土壤中多环芳烃(PAHs)解吸行为的影响.结果表明,表面活性剂的性质、浓度和PAHs的性质、赋存状态影响着土壤中PAHs的解吸.当表面活性剂浓度低于或接近于CMC时,对PAHs解吸没有明显的促进作用.当表面活性剂浓度高于CMC后,表面活性剂对土壤中PAHs的解吸过程有显著的促进作用.具有较低亲水-亲油平衡值(HLB)的表面活性剂对PAHs的增溶性较好.拟合土壤中PAHs的解吸率与PAHs的lgKow值,发现两者之间具有线性关系.人工污染土壤中PAHs解吸效果要好于采油区土壤.

Four types of surfactant were used to study their effects on polycyclic aromatic hydrocarbons （PAHs） desorption from artificially contaminated and oil-contaminated soil. The results show that the desoption of PAHs from soil is affected by the type and concentration of surfactant and also by the character and state of PAHs. Surfactants don＇t improve PAHs desorption from soil when their concentrations are below or near their critical micelle concentration （CMC） values. While, surfactants could obviously enhance the desorption process when the concentrations exceeded the CMC values. The desorption ratios of PAHs were increasing with the increase of surfactant concentrations. Comparatively, lower hydrophile lipophile balance（HLB） can lead to more obvious surfactant solubilization. There were linear relationship between PAils desorption ratio and PAils lgKow value. The desorption ratio of PAils in artificially contaminated soil was higher than in oil-contaminated soil.