Distribution of impurities during low-temperature directed crystallization of water solutions

Trends in the distribution of impurities at low-temperature directed crystallization of water solutions of various concentrations are described and the mechanism of their incorporation in the solid phase is explained. The data on the distribution coefficients of the impurities between the solid and liquid phases are presented. It is shown that the behavior of the impurities in the process of directed crystallization is the same and does not depend on the nature of the macrocomponent. The unique case of CsI is explained due to the negative values of hydration of iodide and cesium ions. It is recommended to use the observed trends for the purification of water or analytical pre-concentration of impurities. The coefficients of enrichment of the impurities after low-temperature directed crystallization of aqueous solutions with different composition and total concentration of the dissolved salts are estimated and their dependencies on the composition and concentration of the aqueous solution are shown.