ELUTION BEHAVIOR OF ACIDS IN ION-EXCLUSION CHROMATOGRAPHY USING A CATION-EXCHANGE RESIN

A large number of strong and weak acids have been subjected to ion-exclusion chromatography by elution with water on a hydrogen-form cation-exchange resin. The column void volume (Vo) and inner volume (Vi) were determined from a calibration graph obtained by plotting the retention volumes (VR) against the first dissociation constants (pKP1) of the acids. The distribution coefficients (Kd) of the acids were calculated from the conventional equation for ion-exclusion chromatography: VR = Vo + KdVi. As the Kd values of most acids are between 0 and 1, it is possible to evaluate by gel chromatography the separation mechanism of acids based on the ion-exclusion effect. © 1979.