Abstract: Four tertiary amine salts, TOA·HCl, N235·HCl, N235·HNO₃, N235·HClO₄were prepared and their interfacial properties were measured. Thermodynamic function of the systems of tertiary amine salt-alcohol-alkane-water was measured by the dilution method and their structure parameters were calculated by using the model of w/o microemul-sion. The results showed that the "droplet" radii R_e<0.5nm. We suggest that the thermo-dynamic stable tetradic system should belong to a kind of reversed micelles contributed by the hydration of alcohol.

Key words: Extractant, Tri-n-octyl amine, N235, Tertiary amine salt, Thermodymanic function