Studies on the phase behavior and solubilization of the microemulsion formed by surfactant-like ionic liquids with ε-β -fish-like phase diagram

摘要

The phase behavior and the solubilization of the microemulsion systems surfactant-like ionic liquids 1-hexadecyl-3-methylimidazohum bromide (C_(16)mimBr), 1-tetradecyl-3-methylirmdazolium bromide (C_(14)mimBr), or 1-dodecyl-3-methylirnidazolium bromide (C_(12)mimBr)/alco-bol/alkane/brine have been studied with ε-β-fish-like phase diagram method at 40 °C and an oil-to-water mass ratio of 1:1. From the ε-β-fish-like phase diagram, the physico-chemical parameters, such as the mass fraction of alcohol in the hydrophile-lipophile-balanced interfacial layer (A~S), and the solubilities of ionic liquid (S~O) and alcohol (A~O) in alkane phase, were calculated. The solubilization of the microemulsion system has been discussed based on the ε-β-fish-like phase diagram. The smaller the oil molecule, the longer the alcohol chain length, and the larger the NaCl concentration in water, the larger the solubilization of the microemulsion system. In this paper, the solubilization of the microemulsion stabilized by both C_(12)mimBr and sodium dodecyl sulfonate (sodium dodecyl sulfate) was also investigated with the ε-β-fish-like phase diagram. The unequi-molar composite of anionic and cationic surfactants can avoid the sedimentation aroused by the strong electrostatic attraction, and an obvious synergism effect in solubilization was obtained.