DETERMINATION OF MICELLE-SOLUTE ASSOCIATION CONSTANTS OF SOME BENZENE AND NAPHTHALENE DERIVATIVES BY MICELLAR HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY WITH BUTANOL AND SODIUM-CHLORIDE ADDITIVES TO MOBILE PHASE

The interaction between some benzene and naphthalene derivatives and sodium dodecyl sulphate and hexadecyltrimethylammonium bromide in the presence of n-butanol and sodium chloride has been evaluated by high-performance liquid chromatography using micellar mobile phases. Micelle-solute association constants are given for the compounds investigated. The results show that addition of n-butanol to the mobile phase decreases the association constant values relative to those in the absence of any additive. Conversely, when sodium chloride is added to the mobile phase, an increase of the association constant is obtained in most cases. Good correlation between free energy of transfer for water-micelles and for octanol-water has been observed.