Modeling of Dissolution of Weakly Soluble Salts in the Presence of Complexing Agents

A mathematical algorithm for ionic equilibria modeling of dissolving weakly soluble salts in the presence of complexing agents or in an overage of an anion that form weakly soluble compounds in water solutions was developed. For numerical methods for calculation of chemical equilibria that involve ionic compounds a set of simplifications are formulated. This simplifications allows to significantly reduce the required computational operations while make it possible to preserve the functionality of numerical methods for solving such ionic equilibria. To verify the algorithm some systems that was studied experimentally were modelled. The maximum divergence between calculated and experimental data was 38%. Some general problems of switch-over from the experimental determination to the mathematical modeling of ionic equilibria and sedimentation in solution were emphasized.