Surfactant-Induced Interactions and Hydraulic Conductivity Chnages in Soil

Sodium dodecylsulfate (SDS) is an anionic surfactant often used to flush hydrophobic organics from contaminated soil during on-site remediation. Batch and column experiments demonstrated the correlations between the aqueous equilibrium concentration and SDS loss from the solution both in the presence and absence of an electrolyte (NaCl). The highest SDS adsorption occurred when the SDS concentration neared the critical micelle concentration (CMC), which was even higher in the presence of NaCl. The effects of soil and surfactant interactions on the hydraulic conductivity of the soil were experimentally examined. A reduction of hydraulic conductivity on the injection of surfactants is linked to the clay content of the soil, the surfactant type and concentration, and the presence of the electrolyte.