Supersolubilization in chlorinated hydrocarbon microemulsions: Solubilization enhancement by lipophilic and hydrophilic linkers

In this paper, the effect of linker molecules on the solubilization capacit y of an anionic surfactant system (sodium dihexyl sulfosuccinate) is studie d. N-Alkyl alcohols are used as lipophilic linkers in middle-phase microemu lsions of trichloroethylene, tetrachloroethylene, and hexane. The lipophili c linker effect increases the solubilization capacity of the anionic surfac tant system. The solubilization parameter for both hydrocarbons and chlorin ated hydrocarbon oil increases as a function of alcohol concentration. As t he alkyl chain length of the alcohol linker molecule increases, the solubil ization capacity increases. Moreover, the longer chain alcohol is more effe ctive at linking oil molecules for hexane than for chlorinated hydrocarbon oils, indicating that the linker effect is more effective for higher equivi lant alkane carbon number (EACN) oils. Sodium mono- and dimethylnaphthalene sulfonate is proposed as a hydrophilic linker to enhance the solubilization of lower EACN oils. The combination of lipophilic and hydrophilic linkers synergistically enhances the solubilization capacity of chlorinated hydroca rbon microemulsions.