Thermodynamics Research Center / ThermoML | Fluid Phase Equilibria

The study of phase behavior of aqueous two-phase system containing [Cnmim]BF4 (n = 2,3,4) + (NH4)2SO4 + H2O at different temperatures

Tang, X.[Xu], Han, J.[Juan], Chen, C.[Chen], Wang, Y.[Yun], Lu, Y.[Yang], Wang, T.[Tingting], Chen, T.[Tong], Ni, L.[Liang]
Fluid Phase Equilib. 2014, 383, 100-107
ABSTRACT
Phase diagram and liquid-liquid equilibrium (LLE) data for the 1-alkyl-3-methylimidazolium tetrafluoroborate ([Cnmim]BF4 (n=2, 3, 4)) + (NH4)2SO4 + H2O aqueous two-phase systems (ATPSs) were determined experimentally at T = (288.15, 298.15, and 313.15) K. The binodal curves were fitted by a four-parameter equation. On the basis of the empirical equation of the binodal curve with the highest accuracy and lever rule, the LLE data were calculated by MATLAB. The tie-lines were correlated by the Othmer-Tobias and Bancraft equations. In particular, the temperature dependence on the binodal curves and tie-lines was discussed, it was found that an decreasing in temperature caused the expansion of two-phase region. Furthermore, the effect of the ionic liquid structure on the phase equilibrium of ATPSs has been studied, the results showed that the ability of phase separation of the IL-based ATPSs follows the order [C4mim]BF4 greater than [C3mim]BF4 greater than [C2mim]BF4.
Compounds
# Formula Name
1 C6H11BF4N2 1-ethyl-3-methylimidazolium tetrafluoroborate
2 C7H13BF4N2 1-propyl-3-methylimidazolium tetrafluoroborate
3 C8H15BF4N2 1-butyl-3-methylimidazolium tetrafluoroborate
4 H8N2O4S ammonium sulfate
5 H2O water
Datasets
The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type Compound-# Property Variable Constraint Phase Method #Points
  • POMD
  • 5
  • 4
  • 1
  • Mass fraction - 4 ; Liquid mixture 1
  • Temperature, K; Liquid mixture 1
  • Mass fraction - 1; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • Titration method
  • 102
  • POMD
  • 5
  • 4
  • 1
  • Mass fraction - 4 ; Liquid mixture 2
  • Mass fraction - 4 ; Liquid mixture 1
  • Mass fraction - 1 ; Liquid mixture 1
  • Temperature, K; Liquid mixture 1
  • Mass fraction - 1; Liquid mixture 2
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 2
  • Liquid mixture 1
  • OTHER
  • OTHER
  • OTHER
  • 12
  • POMD
  • 5
  • 4
  • 2
  • Mass fraction - 4 ; Liquid mixture 1
  • Temperature, K; Liquid mixture 1
  • Mass fraction - 2; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • Titration method
  • 101
  • POMD
  • 5
  • 4
  • 2
  • Mass fraction - 4 ; Liquid mixture 2
  • Mass fraction - 4 ; Liquid mixture 1
  • Mass fraction - 2 ; Liquid mixture 1
  • Temperature, K; Liquid mixture 1
  • Mass fraction - 2; Liquid mixture 2
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 2
  • Liquid mixture 1
  • OTHER
  • OTHER
  • OTHER
  • 12
  • POMD
  • 5
  • 4
  • 3
  • Mass fraction - 4 ; Liquid mixture 1
  • Temperature, K; Liquid mixture 1
  • Mass fraction - 3; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • Titration method
  • 101
  • POMD
  • 5
  • 4
  • 3
  • Mass fraction - 4 ; Liquid mixture 2
  • Mass fraction - 4 ; Liquid mixture 1
  • Mass fraction - 3 ; Liquid mixture 1
  • Temperature, K; Liquid mixture 1
  • Mass fraction - 3; Liquid mixture 2
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 2
  • Liquid mixture 1
  • OTHER
  • OTHER
  • OTHER
  • 12