Supersolubilization in Chlorinated Hydrocarbon Microemulsions: Solubilization Enhancement by Lipophilic and Hydrophilic Linkers

Abstract

In this paper, the effect of linker molecules on the solubilization capacity of an anionic surfactant system (sodium dihexyl sulfosuccinate) is studied. N-Alkyl alcohols are used as lipophilic linkers in middle-phase microemulsions of trichloroethylene, tetrachloroethylene, and hexane. The lipophilic linker effect increases the solubilization capacity of the anionic surfactant system. The solubilization parameter for both hydrocarbons and chlorinated hydrocarbon oil increases as a function of alcohol concentration. As the alkyl chain length of the alcohol linker molecule increases, the solubilization capacity increases. Moreover, the longer chain alcohol is more effective at linking oil molecules for hexane than for chlorinated hydrocarbon oils, indicating that the linker effect is more effective for higher equivilant alkane carbon number (EACN) oils. Sodium mono- and dimethylnaphthalenesulfonate 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 hydrocarbon microemulsions.