Using Molecular Simulations To Develop Reliable Design Tools and Correlations for Engineering Applications of Aqueous Electrolyte Solutions

Many industrial processes involve processing aqueous electrolyte solutions. There is thus a need for accurate theories to predict their thermophysical properties. Recent studies have shown that the size of the hydrated ion plays an important role in determining these properties. In this study, we first used molecular dynamics simulations to estimate the effective hydrated ionic size and the free energy of solvation, and then developed correlations allowing for the prediction of these quantities. The temperature dependence of these solution properties was also investigated. Our studies have shown that the effective (hydrated) size, the charge density, and the free energy of solvation of the ions are strongly interdependent. The effective hydrated ionic size also plays an important role in determining the selectivity of membranes to remove such hydrated ions from solutions, for example, in membrane based desalination processes, and related water purification technologies