AN IMPROVED MODEL FOR THE PREDICTION OF MULTICOMPONENT ION-EXCHANGE EQUILIBRIA

Nonideal behavior for liquid and resin phases is investigated theoretically and experimentally for ion exchange equilibrium of the aqueous ternary system Mg2+, Ca2+, Na+ with Cl-. A semi-theoretical model is proposed in which the Pitzer approach is applied to the solution nonidealities, and the Wilson approach, based on experimental binary data, is applied to the resin. Predictions of the model agree with experimental data for both binary and ternary systems. The predictions of the proposed model are more accurate than those made using existing models.