Liquid-Liquid Equilibria of the Aqueous Two-Phase Systems Composed of the N-Ethylpyridinium Tetrafluoroborate Ionic Liquid and Ammonium Sulfate/Anhydrous Sodium Carbonate/Sodium Dihydrogen Phosphate and Water at 298.15 K

In this work, the phase diagrams and the liquid liquid equilibrium (LLE) data at 298.15 K of the aqueous [EPy]BF4 + ammonium sulfate + H2O, [EPy]BF4 + sodium dihydrogen phosphate + H2O, and [EPy]BF4 + sodium carbonate + H2O two-phase systems were experimentally determined. The Merchuk equation was used to correlate the binodal data of the investigated systems. The tie-line data were correlated according to the Othmer-Tobias and Bancroft equations, the Setschenow equation, and a two-parameter equation. The results indicate that all of these equations can be successfully used to correlate the experimental data of the investigated systems at 298.15 K. Both the calculated effective excluded volume (EEV) and the binodal curves, which were plotted using the mass fractions, indicate the phase-separation abilities of the investigated salts, which follow the following order: Na2CO3 > (NH4)(2)SO4 > NaH2PO4.