Donnan Exclusion - Ion Exclusion Chromatography

Summary Donnan exclusion chromatography is a special type of ion-exchange separation method based on the electrostatic repulsion between the sample ions and fixed ionic groups of an exchanger. The elution behaviour in this chromatography is well explained by the Donnan equilibrium relation of ions between two phases. Practical separations for various oxoanions of phosphorus and for metal cations are reported. Possibilities of this chromatography in other applications are also discussed, as well as theoretical considerations.