Precipitation of water from aqueous mixtures with addition of hydrophilic ions

We examine phase separation in aqueous mixtures at fixed amounts of hydrophilic monovalent ions. When water is the minority component, preferential solvation can stabilize water domains enriched with ions. This ion-induced precipitation occurs in wide ranges of the temperature and the average composition where the solvent would be in one-phase states without ions. The volume fraction of such water domains is decreased to zero as the interaction parameter $\chi$ (dependent on the temperature) is decreased toward a critical value for each average composition.