Retention behavior and simultaneous separation of carboxylic and aromatic acids using ion-exclusion chromatography

Ion-exclusion chromatography using a high-capacity sulphonated polystyrene-divinylbenzene (PS-DVB) resin was evaluated for the separation of a range of carboxylic and aromatic acids. The parameters affecting the retention behaviour of these acids were examined in relation to their chemical structure. Results obtained on the ion-exclusion column for the separation of aromatic acids were similar to those obtained on a C-18 column. The ion-exclusion column exhibited both the ion-exclusion effect for the separation of hydrophilic carboxylic acids and the hydrophobic interaction for the separation of aromatic acids, which offered the possibility of simultaneous separation of carboxylic and aromatic acids by careful selection of separation conditions such as column temperature and content of organic modifier.