Mixing effect of NaCl and surfactant on the remediation of TCB contaminated soil

Abstract

In order to evaluate the mixing effect of NaCl and surfactant on the remediation of TCB contaminated soil, column experiments were performed. Selected soils for this study were two Iowa field soils (Fruitfield, and Webster) and one Korea field soil (Pyeongtaek). We used four nontoxic, water-soluble anionic (DOSL, SLS) and nonionic surfactants (POE20, POE4). 1, 2, 4-trichlorobenzene (TCB) was chosen as the model contaminant. Selected electrolyte for this study was NaCl. The TCB contaminated soils were leached with surfactant solution of 4% (v/v) or 4% (w/v) with or without 5% (w/v) and 10% (w/v) NaCl. As controls, TCB contaminated soils were also leached with deionized water. For the nonionic surfactants (POE20, POE4), the mixing effect of NaCl on the solubilization of contaminant was insignificant. However, much greater mixing effectiveness was observed using anionic surfactant (SLS, single head structure) solutions containing electrolyte (NaCl) from two Iowa soils and one Korea soil. In contrast, another anionic surfactant (DOSL, double head structure) had little mixing effectiveness on the solubilization of TCB from three soils. However, the NaCl mixing effect of DOSL anionic surfactant was found after leaching of 2500 ml solution with Pyeongtaek soil. The effect of NaCl in changing effectiveness was due to Na + (counterion) effects. The maximum recovery of added TCB in column tests was 97% for 4% (w/v) aqueous SLS anionic surfactant + 10% (w/v) NaCl. A little effectiveness of 4% (v/v) DOSL (anionic surfactant) with electrolytes may be due to small adsorption of the double-head sulfate polar heads onto soil particles. Therefore, these results showed that the key factor in the variation of TCB removal effect due to surfactant + NaCl leaching was not surfactant types but surfactant structure. Also, results of this study suggest that the anionic surfactant (SLS) solutions containing electrolyte (NaCl) is a good candidate for surfactant-assisted remediation of TCB contaminated soil.

A Pilot Study for Remediation of Groundwater by Surfactant -Enhanced Soil Flushing

“…However, near the higher end of the pH range (11-14) some of anionic sulphates can begin to hydrolyze and lose activity Rosano, 1984, Adeel andLuthy, 1995;Cases et al, 2002;Kim et al, 2005). The cause of the lower effect obtained from this study compared to Lee et al (2008) results might be attributed to the differences in model contaminants and soils. Also, hydrogen ion concentration in surfactant solution was an important factor in surfactant effectiveness (Lee et al, 2001c).…”

“…In a previous other study (Lee et al, 2008), much greater effectiveness was observed using surfactant solutions containing NaOH. In that study we found that NaOH increased the effectiveness of a nonionic surfactant (POE, trade name Pluronic L44) by 30%, an anionic surfactant (TDCA, trade name Sandopan JA36) by 34%, and water by 10% in a pure sand column.…”

“…In that study we found that NaOH increased the effectiveness of a nonionic surfactant (POE, trade name Pluronic L44) by 30%, an anionic surfactant (TDCA, trade name Sandopan JA36) by 34%, and water by 10% in a pure sand column. The effect of NaOH in changing effectiveness is not due to Na + counter-ion effects, but rather to the OH − based on experimental results (Lee et al, 2008). Increased micelle formation and decreased surface tension of surfactant solution at high pH may have affected our results (Lee and Cody, 2001c).…”

Cloud-Point Extraction and Selective Spectrophotometric Determination of Pb ( II ) and Cu ( II ) Using Synthesized N1, N2- Diphenylhydrazine-1, 2-Dicarbothioamide and an Anionic Surfactant

“…This decrease in extraction is possibly due to increase of micelle aggregation number (size of micelle) and decrease the critical micelle concentration (CMC). [15,21] Different solvents such as acetonitrile, ethanol, methanol, THF, mixture of acetonitrile-water and mixture of acetonitrile-ethanol were tested. The aim was to select a solvent or a mixture so that the surfactant rich phase and the extracted compounds could be dissolved completely.…”

The Effect of the Mixture of Nonionic Surfactant and Bioactive Agent for Surfactant-enhanced Soil Flushing (SESF) of TCB Contaminated Soil

“…A major concern related to the effectiveness of SESF is surfactant losses. Nonionic surfactants seem to be less susceptible than ionic (anionic / cationic) surfactants to precipitation losses due to an increase in their solubility and steric constraints (Rosen, 1989;Lee et al, 2008). Therefore, the objective of this study was to find the effect of the mixture of the nonionic surfactant and bioactive agent that solubilizes TCB present as a contaminant for SESF.…”