Thermodynamics Research Center / ThermoML | Thermochimica Acta

Phase equilibria in aqueous two-phase systems containing [Bmim]BF4 and ammonium sulfate/sodium carbonate at different temperatures: Experimental and correlation

Wang, Y.[Yu], Xu, X.[Xiaohui], Yan, Y.[Yongsheng], Han, J.[Juan], Zhang, Z.[Zulei]
Thermochim. Acta 2010, 501, 1-2, 112-118
ABSTRACT
The phase-forming salts and corresponding phase-forming ability for 1-butyl-3-methylimidazolium-tetrafluoroborate ([Bmim]BF4)-based aqueous two-phase were discussed. Experimental liquid + liquid equilibrium (LLE) measurements and the phase diagram have been determined for aqueous two-phase systems containing [Bmim]BF4 and (NH4)2SO4 at T = (298.15, 308.15, and 318.15) K. The Merchuk equation was used to correlate the binodal curves of these systems. Simultaneously, the effects of temperature on the phase-forming ability in the investigated system have also been studied on the basis of a salting-out coefficient obtained from fitting the tie-line data to a Setschenow-type equation for each temperature. Additionally, the phase-forming ability of (NH4)2SO4 and Na2CO3 for [Bmim]BF4-based aqueous two-phase was compared and discussed.
Compounds
# Formula Name
1 C8H15BF4N2 1-butyl-3-methylimidazolium tetrafluoroborate
2 H8N2O4S ammonium sulfate
3 H2O water
4 CNa2O3 sodium carbonate
5 H2NaO4P sodium dihydrogen phosphate
6 Na2O3S sodium sulfite
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
  • 3
  • 2
  • 1
  • Mass fraction - 2 ; Liquid mixture 2
  • Mass fraction - 2 ; Liquid mixture 1
  • Mass fraction - 1 ; Liquid mixture 1
  • Temperature, K; Liquid mixture 1
  • Mass fraction - 1; Liquid mixture 2
  • Pressure, kPa; Liquid mixture 2
  • Liquid mixture 2
  • Liquid mixture 1
  • Phase equilibration
  • Phase equilibration
  • Phase equilibration
  • 10
  • POMD
  • 3
  • 2
  • 1
  • Mass fraction - 2 ; 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
  • 157
  • POMD
  • 4
  • 3
  • 1
  • Mass fraction - 4 ; 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
  • 76
  • POMD
  • 5
  • 3
  • 1
  • Mass fraction - 5 ; 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
  • 38
  • POMD
  • 3
  • 6
  • 1
  • 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
  • 19