[Desorption of polycyclic aromatic hydrocarbons from soil in presence of surfactants].

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 PAHs desorption ratio and PAHs lgKow value. The desorption ratio of PAHs in artificially contaminated soil was higher than in oil-contaminated soil.