Microemulsion Phase Behavior of Aerosol-OT Combined with a Cationic Hydrotrope in the Dilute Region

Abstract

The phase behavior of systems containing minimum amounts of sodium bis (2-ethylhexyl) sulfosuccinate with equimolar ratio of tetra ethyl ammonium chloride were studied as a function of salt concentration and alkane carbon number at ambient temperature. Visual inspection as well as cross polarizers were used to detect anisotropy. Solubilization ratios for oil and brine in the middle phases were measured and used to calculate the interfacial tension. Ultra-low interfacial tension values were predicted for the systems containing heptane, octane and nonane as model oil. Different phase behavior was observed for systems with higher alkane number.

Keywords:

• Aerosol-OT
• cationic hydrotrope
• microemulsion
• middle phase

Acknowledgments

This work was supported by the Swedish Research Council.

Notes

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