Monte Carlo simulation of binary surfactant/contaminant/water systems

Surfactant-enhanced remediation (SER) is an effective approach for the removal of absorbed hydrophobic organic compounds (HOCs) from contaminated soils. The solubilization of contaminants by mixed surfactants with attractive and repulsive head–head interactions was studied by measuring the micelle–water partition coefficient (KC) and molar solubilization ratio (MSR) using the lattice Monte Carlo method. The effect of surfactant mixing on the MSR and KC of contaminants displayed the following trend: C4 > C3 > C2.Synergistic binary surfactant mixtures showed greater solubilization capacities for contaminants than the corresponding individual surfactants. Mixed micellization parameters, including the interaction parameter β, and activity coefficient fi, were evaluated with Rubingh's approach.Synergistic mixed-surfactant systems can improve the performance of surfactant-enhanced remediation of soils and groundwater by decreasing the amount of applied surfactant and the cost of remediation.

Graphical abstractSnapshots of (a) a micelle, (b) cross-section of micelle with a 50:50 volume fraction of surfactant in a synergistic system.Figure optionsDownload full-size imageDownload high-quality image (221 K)Download as PowerPoint slideHighlights► The water solubility of contaminants by single surfactant with lattice MC model. ► The water solubility of contaminants by antagonism mixed surfactant systems. ► The water solubility of contaminants by synergism mixed surfactant systems.