Mcl (m = Na, K And Rb, Cs) In The Mixed Solvent Of Water / Polyhydric Alcohol Solubility, Density And Refractive Index

The phase equilibrium investigations of the alkali-metal salts in mixed solvents can not only generate a purified method, but also provide basic data to develop their solution chemistry.This paper mainly includes three parts:preface section, experimental section, and results and discussion.In the preface section, we introduce the significance of phase equilibrium for alkali metal salts, and the investigation of alkali metal salts-water systems, alkali metal salts-alcohol-water systems, alkali metal salts-poly alcohol-water systems and alkali metal salts-ionic liquids-water systems.In the experimental section, we introduce the preparation method of saturated solution and the analysis method of chloride salt.The results and discussion section have discussed three ternary systems and three quaternary systems:(1) solubilities, densities, and refractive indices have been measured for the ternary systems ethylene glycol/1,2-propylene glycol/glycerin+NaCl/KCl/RbCl/CsCl+H2O at 15,25 and 35℃with mass fractions of polyhydroxy alcohol ranging from 0 to 1.0. On the other hand, the density and refractive index of unsaturated solutions were also determined for the same ternary systems with varied undersaturated salt concentration (2) Polynomial equations of fit are proposed for the solubility of the saturated solutions as a function of the mass fraction of polyhydroxy alcohol. The equations proposed also account for the density and refractive index for the saturated solutions. Values for both the properties were also correlated with the salt concentrations and proportions of polyhydroxy alcohol in the undersaturated solutions. In all the cases, the presence of polyhydroxy alcohol significantly reduces the solubility of the salts in the aqueous solution (3) we also discussed the impact of the hydroxyl and carbon chain on the density and refractive index for the saturated systems ethylene glycol/1,2-propylene glycol/glycerin+NaCl/KCl/RbCl/CsCl+H2O at 25℃.