Thermodynamics Research Center / ThermoML | Fluid Phase Equilibria

LLE for (water + ionic liquid) binary systems using [Cxmim][BF4] (x = 6, 8) ionic liquids

Maia, F. M.[Filipa M.], Rodriguez, O.[Oscar], Macedo, E. A.[Eugenia A.]
Fluid Phase Equilib. 2010, 296, 2, 184-191
ABSTRACT
Liquid-liquid equilibrium diagrams were determined for (IL + water) systems using the family of ILs 1-alkyl-3-methylimidazolium tetrafluoroborates, where the alkyl groups are hexyl and octyl ([Cxmim][BF4] with x = 6 and 8). The gravimetric method was used to determine the equilibrium compositions at temperatures ranging from 278.15 to 340.15 K. Both systems present an upper critical solution temperature (UCST), which increases from [C6mim][BF4] to [C8mim][BF4]. The experimental data were correlated using the NRTL and eNRTL models. The binary interaction parameters were calculated for each system and model, and good agreement between experimental and calculated equilibrium compositions was obtained. Finally, the apparent Gibbs energy, enthalpy and entropy of water solution in the ILs were calculated using a modified van t Hoff equation. The three thermodynamic functions were found to be positive for both ILs.
Compounds
# Formula Name
1 H2O water
2 C10H19BF4N2 1-hexyl-3-methylimidazolium tetrafluoroborate
3 C12H23BF4N2 1-methyl-3-octylimidazolium tetrafluoroborate
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
  • 2
  • Mass fraction - 2 ; Liquid mixture 2
  • Temperature, K; Liquid mixture 2
  • Pressure, kPa; Liquid mixture 2
  • Liquid mixture 2
  • Liquid mixture 1
  • OTHER:UFactor:4:sMethod:Water mass boiled off
  • 13
  • POMD
  • 1
  • 2
  • Mass fraction - 2 ; Liquid mixture 1
  • Temperature, K; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • OTHER:UFactor:4:sMethod:Water mass boiled off
  • 13
  • POMD
  • 1
  • 3
  • Mass fraction - 3 ; Liquid mixture 2
  • Temperature, K; Liquid mixture 2
  • Pressure, kPa; Liquid mixture 2
  • Liquid mixture 2
  • Liquid mixture 1
  • OTHER:UFactor:8:sMethod:Water mass boiled off
  • 15
  • POMD
  • 1
  • 3
  • Mass fraction - 3 ; Liquid mixture 1
  • Temperature, K; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • OTHER:UFactor:8:sMethod:Water mass boiled off
  • 15