Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

Liquid Liquid Equilibrium of Various Aqueous Two-Phase Systems: Experiment and Correlation

Liu, Y.[Yang], Feng, Y.-Q.[Yuan-Qi], Zhao, Y.[Yongjie]
J. Chem. Eng. Data 2013, 58, 10, 2775-2784
ABSTRACT
Liquid liquid equilibrium (LLE) data for aqueous two-phase systems (ATPS) were discussed through experiment and correlation at 25 deg C, in polymer organic salt ATPS, alcohol salt ATPS, and polymer surfactant ATPS, respectively. Various binodal curves empirical equations combined with simple experiments were applied to determine the LLE data with as wide composition concentrations as possible. The tie-line length (TLL) ranges of the investigated ATPS were also determined experimentally. Both the two-phase regions and the TLL ranges of polymer organic salt ATPS or alcohol salt ATPS were generally wider than polymer surfactant ATPS, which would be caused by the solubility of two compositions in different ATPS. The parameters of tie-line equations including Othmer Tobias and Bancroft equations were further obtained by LLE data, which can be used to predict the unknown tie-line data. The experimental volume ratios of various tie-lines in ATPS showed good agreement with the predicted data based on the small standard deviation (SD less than 0.05). Compared to the complicated experimental method for the determination of ATPS LLE data, the binodal curves and tie-line empirical equations combined with simple experiments can provide the LLE data for various ATPS.
Compounds
# Formula Name
1 C2H6O ethanol
2 H8N2O4S ammonium sulfate
3 HK2O4P dipotassium hydrogen phosphate
4 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
  • 1
  • 4
  • 2
  • Mass fraction - 2 ; Liquid mixture 1
  • Mass fraction - 1; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Temperature, K; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • Titration method
  • 23
  • POMD
  • 1
  • 4
  • 2
  • Mass fraction - 2 ; Liquid mixture 1
  • Mass fraction - 1 ; Liquid mixture 2
  • Mass fraction - 2 ; Liquid mixture 2
  • Mass fraction - 1; Liquid mixture 1
  • Temperature, K; Liquid mixture 2
  • Pressure, kPa; Liquid mixture 2
  • Liquid mixture 1
  • Liquid mixture 2
  • OTHER
  • OTHER
  • OTHER
  • 7
  • POMD
  • 1
  • 4
  • 3
  • Mass fraction - 3 ; Liquid mixture 1
  • Mass fraction - 1; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Temperature, K; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • Titration method
  • 25
  • POMD
  • 1
  • 4
  • 3
  • Mass fraction - 3 ; Liquid mixture 1
  • Mass fraction - 1 ; Liquid mixture 2
  • Mass fraction - 3 ; Liquid mixture 2
  • Mass fraction - 1; Liquid mixture 1
  • Temperature, K; Liquid mixture 2
  • Pressure, kPa; Liquid mixture 2
  • Liquid mixture 1
  • Liquid mixture 2
  • OTHER
  • OTHER
  • OTHER
  • 7