| Conventional remediation techniques have not been very effective in treating soil and groundwater contaminated with chlorinated solvents. The incorporation of surfactants may enhance the efficiency of current remediation techniques, but greatly complicate the post treatment of surfactant-laden waste streams containing volatile contaminants. The purpose of this study was to determine the effect of anionic and nonionic surfactants on the air-water partitioning of three prominent chlorinated solvents, tetrachloroethylene (PCE), trichloroethylene (TCE), and cis-dichlorethylene (DCE). Results showed that the apparent Henry's Law constants of the chlorinated solvents were significantly reduced in the presence of all four test surfactants. On a CMC basis, the effect on the air-water partitioning was greater for anionic surfactants than nonionic surfactants. However, on a mass concentration basis the nonionic surfactants had a greater effect on the air-water partitioning. The more hydrophobic solvent PCE had the greatest partitioning into the micellar phase among the three test solvents based on extra-micellar fraction (fex) and micellar partitioning coefficient (KM) calculations. |
