Solvation Behavior For Binary Mixtures Of 1,3-dialkylimidazolium ILs With Water

The binary mixtures of water and 1,3-dialkylimidazolium ILs were selected here as solvents systems to investigate the solute-solvent and solvent-solvent interactions on the preferential solvation of solvatochromic indicators at 25℃. The empirical solvatochromic parameters, dipolarity/polarizability (π*), hydrogen-bond basicity (β), hydrogen-bond acidity (a) and Reichardt’s polarity parameters (ETN) were measured from the UV-vis spectra shift of 4-nitroaniline,4-nitroanisole and Reichardt’s dye. The solvent properties of every binary mixtures were influenced by both the nature of cations and anions, rather than single one of them. Both the symmetry of the cations and the electronegativity and magnitude of anions are the determining factors. The water content has a directly and unneglected influence on the imidazolium-based IL/water binary systems. All systems showed non-ideal behavior. The dissolution capacity of IL/water systems are related to net basicity (β-α). The preferential solvation model has been utilized to gather information on macro-interactions in imidazolium-based IL/H2O binary mixtures. The result showed that the dye was preferential solvated on the trend:IL>IL/water complex>water.