RETENTION BEHAVIORS AND SEPARATION OF CARBOXYLIC-ACIDS BY ION-EXCHANGE CHROMATOGRAPHY

The use of high-performance suppressed ion chromatography for the sepa ration of aliphatic carboxylic acids has become an attractive and viab le method during the past years. This paper summarises and critically concludes that some new results have been achieved in separation and d etection of low-molecular-mass organic anions. Theoretical and practic al considerations of ion-exchange selectivity to control retention beh aviour are presented. The major factors that determine the separation ability of ion-exchange chromatography (pK(a) values, the aliphatic na ture and valency of solutes, eluent pH and the chemical composition of stationary phases) are discussed. The question of isocratic vs. gradi ent elution and different separation modes are examined briefly. The p otentials and limitations of the developed methods and their specific application areas are outlined, (C) 1998 Elsevier Science B.V. All rig hts reserved.