GENERAL METHOD FOR THE STUDY OF SOLUTE-SURFACTANT ASSOCIATION EQUILIBRIA OF VOLATILE SOLUTES BY HEADSPACE GAS CHROMATOGRAPHY

摘要

A general methodology for measurement of solute-surfactant associations for volatile solutes based on headspace gas chromatography has been developed. A general theoretical model is also developed to treat the experimental data that requires no analytical solute standard. The model is applicable to any volatile solutes, especially very hydrophobic solutes such as n-alkylbenzenes, for which accurate aqueous standard solutions cannot be prepared. Parameters such as solute-surfactant association constant, solute-micelles association constant and partition coefficient, critical micelles concentration, intramicellar mole fraction, and intramicellar activity coefficient of n-alkylbenzenes are obtained as a function of aqueous surfactant concentrations.