Abstract

The role of surfactants in remediation of metal contaminated soils is a subject that has gained considerable scientists attention in many related research fields. In the present study, surfactants with and without a chelating agent are used to remove Cu (II), Cd (II), and Pb (11) from an artificially contaminated sandy soil. SDS (sodium dodecyl sulfate) and AOT (sodium dioctyl sulfosuccinate) are the anionic surfactants. Tx-100 (Triton x100) is the nonionic surfactant and EDTA (Disodium ethylenediamine tetraacetate) is the chelating agent selected to form the extracting solutions. Batch and column tests were conducted at room temperature (22{493}C ± 2{493}C. Batch results indicated that replacing distilled water with SDS can enhance the metal removal rates by a factor of 5.5, 28.8, and 29.1 for Cu (11), Cd (II), and Pb (II), respectively. A combination of SDS and EDTA was found to be an ideal extracting solution for both batch and column tests. In column tests, the mixture was able to remove about 83%, 88%, and 70% of Cu (II), Cd (II), and Pb (II) respectively. This study shows that SDS is an effective extracting reagent. Therefore, it may be considered for in-situ remediation of metal contaminated sites. Results related to competition and interference among metals to get adsorbed or desorbed to sandy soils, are also briefly presented. Lastly, the effect of flow rate and aging of contaminants are discussed.