Fish-shaped Phase Diagram Of The Cation-anion Surfactant Complex Phase Microemulsion System Phase Behavior And Solubilization

This thesis contains three parts: Part I. Progress in the research and application of various phase diagrams of microemulsions. Part II. Studies on the middle-phase microemulsion formed by sodium dodecyl sulphate and 1-hexadecyl-3- methylimidazolium bromide mixed surfactants with aδ-γfishlike phase diagram. Part III. Studies on the middle-phase microemulsion formed by sodium dodecyl sulfonate and 1-dodecyl-3-methylimidazolium bromide mixed surfactants with aε-βfishlike phase diagram.Part I. Progress in the research and application of various phase diagrams of microemulsions. The characters and progresses of three kinds of microemulsin phase diagrams, Winsor phase diagram,δ-γfish-like phase diagram andε-βfishlike phase diagram, were introduced. The advantages and disadvantages of the three kinds of diagrams were compared. Winsor phase diagram is intuitionistic and simple, but only a few physico-chemical parameters are obtained from this kind of phase diagram. The physico-chemical parameters, such as the composition of the hydrophile-lipophile balanced layer, could be obtained but could not be obtained with enough accuracy fromδ-γfish-like phase diagram. However, the physico-chemical parameters could be calculated fromε-βfish-like phase diagram accurately.The application of the phase inversion of Winsorâ…¢â†'Winsorâ… â†'Winsorâ…¢in the organic contaminant separation is revewed. When the phase of the system inverts from Winsorâ…¢to Winsor I, the organic contaminant solubilizated in the middle-phase microemulsion was released, since the solubilization power of the organic contaminant is smaller in Winsor I type microemulsion than that in Winsor III microemulsion.At last, the problems existed in the research of the microemulsin phase behavior and the contents of this theses were summarized. Part II. Studies on the middle-phase microemulsion formed by sodium dodecyl sulphate and 1-hexadecyl-3-methylimidazolium bromide mixed surfactants with aδ-γfish-like phase diagram.In this chapter, the phase behavior and the solubilization of the middle-phase microemulsion containing sodium dodecyl sulphate (SDS) and 1-hexadecyl- 3-methylimidazolium bromide (C16mimBr)/n-butanol/n-alkane/brine (2.5% NaCl) have been studied with aδ-γfishlike phase diagram. From the mid-line of the middle phase, the composition of the hydrophile-lipophile balanced interfacial layer can be obtained. Some other related parameters, such as the solubilities of surfactant and n-butanol in n-octane were calculated from the mass balanced equations. The solubilization power of the microemulsion formed by the composite surfactant SDS/C16mimBr was examined, and the synergism was found to be existed.Part III. Studies on the middle-phase microemulsion formed by sodium dodecyl sulfonate and 1-dodecyl-3-methylimidazolium bromide Mixed Surfactants with aε-βfishlike phase diagram.The phase behavior of the microemulsion system sodium dodecyl sulfonate/ 1-dodecyl-3-methylimidazolium bromide/alcohol/alkane/water was studied with aε-βfishlike phase diagram method.Different from theδ-γfishlike phase diagram, the fish head is downward and the fish tail is upward in theε-βfishlike phase diagram. The composition of the balanced interfacial layer was calculated by using theε-βtype HLB plane equation, and some other physicochemical parameters, such as the solubilities of surfactant and alcohol in the oil phase can be obtained by using the corresponding equations. Theε-βtype HLB plane equation is a straight line.The coordinates (βE,εE) of the fish tail reveal the mass fractions of surfactant and alcohol in the total system, respectively, while equal amounts of water and oil are solubilized in a single phase.βE andεE are better thanγE in evaluating the solubilization of the system.The solubilization power of the microemulsion formed by the composite surfactant AS/C12mimBr was examined in details. The effects of inorganic salts, oils and alcohols on both the phase behavior and the composition of the interfacial layer were also investigated.