Partitioning of polycyclic aromatic hydrocarbons to solid-sorbed nonionic surfactants

The partition of hydrophobic organic compounds (HOCs) into solid-sorbed surfactant has a crucial role in describing and predicting the distribution of HOCs in solid-water-surfactant systems. The experimental results of this study indicated that the partition coefficients of polycyclic aromatic hydrocarbons (PAHs) into the solid-sorbed surfactant (K-sm) increased with an increase in the sorption amount of surfactants onto solid and reached a stable maximum value (K-sm(m)) at the sorption of surfactants in saturation state, at which the solid surface was completely covered with the surface micelle (or admicelle). The fitted K-sm(m) values for PAHs with different surfactants were found to have a good linear relationship with the corresponding partition coefficient of PAHs to surfactant micelles in solution (K-mc), and then a model was developed to describe and predict the distribution of PAHs in solid-water-surfactant systems. These results are of practical interest for developing effective and safe surfactant-enhanced remediation technologies. (c) 2007 Elsevier Ltd. All rights reserved.