Halogenated Imidazole Type Ionic Liquid + Rb ₂ SO ₄ / Cs ₂ SO ₄ + H < / T> O Ternary System And Its Related Physical And Chemical Properties

Ionic liquids was widely used in organic synthesis, extraction and separations, environmental science, materials science, industrial catalysis, electrochemistry and other fields, due to low melting point, excellent electric conductivity, wide electrochemical window, low vapor pressure and so on. In this paper, phase equilibrium and the physical and chemical properties of the ternary systems imidazoles ionic liquids+RD2SO4/CS2SO4+H2O were carried out. The main contents are as follows:(1) The solubility, density and refractive index of [Cnmim]Cl/[Cnmim]Br (n=2,4,6,8)+Rb2SO4/Cs2SO4+H2O ternary systems at different temperature were determined. When increasing the concentration of ionic liquids, the solubility of Rb2SO4and CS2SO4was decreased and refractive index of the solution was increased. However, the density decreased firstly, and then increased. The temperature effect on solubility is that the higher temperature, the larger solubility is. But density and refractive index curves at different temperatures all have interactions. The longer the carbon chain, the bigger the molecular weight of the ionic liquids, the larger solubility is.(2)For [Cnmim]Cl/[Cnmim]Br+CS2SO4+H2O systems, different phenomenon was observed for different ionic liquids. When carbon chain of ILs was increased, two liquid phases was detected. For these systems, Through dynamic laser monitoring system for auxiliary, the binodal curves were determined by cloud point method. The experimental data were correlated by Merchuk equation and semi-emperical equation, and competed their results. The tie-line data was fitted using Othmer-Tobias and Bancroft equation. The result shows that the temperature rise is not conducive to salting out effect. The order of forming two liquid phase formation is:[C6mim]Br>[Cgmim]Br>[C4mim]Br,[C6mim]Cl>[C8mim]Cl.