Modelling Multi-Component Ion Exchange Equilibrium Behaviour

Abstract

The ability to accurately predict ion exchange equilibria is vital if efficient ion exchange processes and equipment are to be designed. This is particularly true when three or more ionic species are competing with one another for sites on the exchanger. Many models to predict ion exchange equilibrium behaviour have been developed over recent years. The complexity of the models have increased from simple ones which assume ideal behaviour in both phases to ones which can predict behaviour in four-component systems based upon binary equilibrium data. This paper will critically review the models developed in recent years and propose a series of requirements that any proposed ion exchange equilibrium model should meet.