Synergetic effect of cationic surfactive ionic liquid C12mimBr and anionic surfactant SDBS on the phase behavior and solubilization of microemulsions

Synergistic effect of the surfactant mixture of ionic liquid 1-dodecyl-3-methylimidazolium bromide (C12mimBr) and sodium dodecyl benzene sulfonate (SDBS) on the phase behavior and the solubilization ability of the microemulsion systems was studied with ɛ–β fishlike phase diagrams. The middle-phase microemulsion appears at the range of the mole ratios of C12mimBr to SDBS 0–0.1 and 0.7–1.0. The solubilization ability (SP*) of the mixed surfactant based microemulsion systems increased markedly compared to the pure C12mimBr or SDBS-based microemulsion systems. The mixture of C12mimBr and SDBS also shows preferable synergism in the solubility of the alcohol and the composition of the interfacial layer. The effects of alcohols, alkanes and NaCl concentrations on the ɛ–β fishlike phase diagrams of C12mimBr/SDBS (molar ratio = 8:2)/alcohol/alkane/brine microemulsion systems were also investigated.

► The ɛ–β fishlike phase diagrams containing C12mimBr and SDBS were constructed.
► Middle-phase microemulsion appears at C12mimBr/SDBS molar ratios 0–0.1 and 0.7–1.0.
► Synergistic effect of the surfactant mixture on the solubilization ability exists.
► Alcohol, alkane and salinity affect the ɛ–β fishlike phase diagrams.