Anionic / Cationic Surface Active Agent Microemulsion Liquid Phase Behavior And Thermodynamic Properties,

This thesis includes four parts. Part I. Introduction of the progress in research of microemulsion phase behavior using phase diagrams and microemulsion structural parameters using dilution method. Part II. Research on the structural parameters of the W/O microemulsion systems anionic surfactant (SDS, AS)/alcohol/alkane/water. Partâ…¢. Research on the structural parameters of the W/O microemulsion systems cationic surfactant (SDS, AS)/alcohol/alkane/water. Part IV. Research on the structural parameters of the W/O microemulsion systems formed by formed by anionic and cationic mixed surfactants.Partâ… . Introduction of the progress in research of microemulsion phase behavior using phase diagrams and microemulsion structural parameters using dilution method.1. The studies on the phase behavior of microemulsions with phase diagrams were introduced, such as Winsor phase diagram, quasi-ternary phase diagram andδ-γ"fish-like" phase diagram, their advantages and disadvantages were discussed.2. The research methods of the W/O microemulsion was introduced3. The principle of the dilution method, as well as the calculation of the structural parameters of the W/O microemulsion droplets were introduced.Partâ…¡. Research on the structural parameters of the W/O microemulsion systems anionic surfactant (SDS, AS)/alcohol/alkane/water.1. The W/O microemulsion systems SDS / alcohol / alkane / brine and AS / alcohol / alkane / brine were studied with the dilution method. The structural parameters of the W/O microemulsion droplets were calculated. The research shows that SDS was easier to form W/O microemulsion than AS.2. The influences of water content, alkane, salinity on the formation of microemulsion system formed by SDS and AS were discussed. The results indicate that the water content and the chain length of alkane molecules were unfavorable, while salts were favorable to the formation of the W/O microemulsion. In addition, the effect of different short-chain alcohols on the formation of the W/O microemulsion system formed by SDS was studied. It was found that the increase of the alcohol chain length promotes the formation of the W/O microemulsion.Partâ…¢. Research on the structural parameters of the W/O microemulsion systems cationic surfactant (SDS, AS)/alcohol/alkane/water.1. The structural parameters of the W/O microemulsion droplets for the systems cationic surfactant CTAB/alcohol/alkanes/brine were researched, and the effects of water content, alkane, salinity on the structural parameters were studied. It was found that the effect was nearly the same as that on the anionic surfactant-based microemulsion systems.2. The plots of the radii of the water nuclear RW vs Vwater, RW vs n, the number of carbon atoms of the alkanes, and RW vs the concentration of the salt shows linear relationships. The alcohol transfer free energyΔG câ†'i vs Vwater andΔG câ†'i vs n were also linear relationships.Part IV. Research on the structural parameters of the W/O microemulsion systems formed by formed by anionic and cationic mixed surfactants.1. The structural parameters of the microemulsion systems formed by CTAB and AS mixtures in different molar ratios were obtained using the dilution method.The effects of water contents, alkanes and salinity on the formation of the W/O microemulsion systems were studied. It was found that the effect of these three factors was nearly the same to that on the microemulsion systems formed by anionic or cationic surfactant systems.2. The relationship RW vs Vwater was linear. 3. The synergic effect on the formation of the W/O microemulsion exists between AS and CTAB, which can be seen from the alcohol transfer free energy values.