Phase Behavior and Solubilization of Microemulsion Systems Containing Imidazolium Type Surfactant C_nmimBr and Butyric Acid as Cosurfactant

摘要

The phase behavior and solubilization of two microemulsion systems l-alkyl-3-methylimidazolium bromide (C_nmimBr, n = 12,14,16)/butyric acid/hexane/brine (5% NaCI) and C_nmimBr/l-butanol/hexane/brine (5% NaCI) were studied and compared. The physico-chemical parameters, such as the solubility (ε_B) of the cosurfactant, the mass fraction of the cosurfactant in the interfacial layer (A~s), and the solubilization ability (SP*) of the two microemulsion systems were calculated and discussed. As the carbon chain length of C_nmimBr molecules increases, SP* increases, and the difference of SP* values between the two microemulsion systems is reduced. The effects of aqueous and oleic phases and temperatures on the phase behavior and solubilization of C_(14)mimBr/butyric acid/alkane/aqueous phase microemulsion systems were also discussed.