Imidazole Ionic Liquid [C _N Mim] Cl / Br (n = 2,4,6,8) + MNO _{3 Na, K, Rb, Cs ) + H 2 O System}

The research on the solid-liquid phase equilibrium of alkali metal salt in the mixed solvent is significant to the separation and purification of salt and consummate the thermodynamic data. It can blaze new trails and reform the conventional approach that the traditional organic solvent is superseded by the novel green solvent ionic liquid.This work was devoted to propose a series of ternary systems composed of1-alkyl-3-methylimidazolium chloride/bromide+NaNO3/KNO3/RbNO3/CsNO3+water ([C2mim]Cl=1-ethyl-3-methylimidazolium chloride,[C4mim]Cl=1-butyl-3-methylimidazolium chloride,[C6mim]Cl=1-hexyl-3-methylimidazolium chloride,[Csmim]Cl=1-octyl-3-methylimidazolium chloride,[C2mim]Br=1-ethyl-3-methylimidazolium bromide,[C4mim]Br=1-butyl-3-methylimidazolium bromide,[C6mim]Br=1-hexyl-3-methylimidazolium bromide,[C8mim]Br=1-octyl-3-methylimidazolium bromide). The solubility, density and refractive index data for these ternary systems had been experimentally determined at298.15K. The all systems that we studied are not aqueous two-phase systems under the selected temperature and concentration, In particular, the effects of the ionic liquid structure and the types of inorganic salts on the phase equilibrium property of ternary systems have been discussed in detail. The mass fraction of nitrate salts decrease with increasing ionic liquid composition, and increase with the side alkyl chain of ionic liquid. The density of ternary systems is decreased when the side alkyl chain of ionic liquid increased and anionic radius of ionic liquid decreased. But the refractive index increases with increasing ionic liquid, and decreases when the side alkyl chain of ionic liquid increased. The experimental data of density, refractive index and solubility of saturated solutions for these systems were correlated using polynomial equations Y=A+Bw1+Cw12+Dw13.