Thermodynamics Research Center / ThermoML | Fluid Phase Equilibria

Phase behavior of imidazolium and phosphonium tetrafluoroborates with dihydroxy alcohols

Makowska, A.[Anna], Papis, P.[Paulina], Szydlowski, J.[Jerzy]
Fluid Phase Equilib. 2014, 382, 100-106
ABSTRACT
Liquid-liquid equilibrium curves for 1-ethyl-3-methylimidazolium tetrafluoroborate -[C2MIM,BF4], 1-butyl-3-methylimidazolium tetrafluoroborate -[C4MIM,BF4] and trihexyl(tetradecyl) phosphonium tetrafluoroborate -[P6,6,6,14,BF4] with chosen dihydroxy alcohols and their deuterated analogues have been determined. All fourteen obtained phase diagrams are described by the upper critical solution temperature (UCST) type behavior. The mutual solubility of 1-ethyl-3-methylimidazolium tetrafluor- oborates decreases with the increase in alkyl chain of 1,2-dihydroxy alcohols but the opposite effect was observed for the ionic liquid with phosphonium cation. The impact of the hydroxyl group position in butanediol molecule on miscibility with trihexyl(tetradecyl) phosphonium tetrafluoroborate was examined. The results lead to the conclusion that vicinal(1,2 and 2,3)-butanediols are much better miscible than more polar (1,3) and (1,4) isomers. Deuterium substitution in both hydroxyl groups of investigated diols generates downward isotope shift of UCST both for phosphonium and imidazolium based ionic liquids thus making the miscibility better in each case.
Compounds
# Formula Name
1 C32H68BF4P trihexyl(tetradecyl)-phosphonium tetrafluoroborate
2 C6H11BF4N2 1-ethyl-3-methylimidazolium tetrafluoroborate
3 C8H15BF4N2 1-butyl-3-methylimidazolium tetrafluoroborate
4 C2H6O2 1,2-ethanediol
5 C3H8O2 1,2-propanediol
6 C4H10O2 1,3-butanediol
7 C4H10O2 1,2-butanediol
8 C4H10O2 2,3-butanediol
9 C5H12O2 1,2-pentanediol
10 C6H14O2 1,2-hexanediol
11 C4H8D2O2 butane-1,2-diol-d2
12 C6H12D2O2 hexane-1,2-diol-d2
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
  • 4
  • 2
  • Liquid-liquid equilibrium temperature, K ; Liquid mixture 1
  • Mole fraction - 2; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • VISOBS
  • 12
  • POMD
  • 5
  • 2
  • Liquid-liquid equilibrium temperature, K ; Liquid mixture 1
  • Mole fraction - 2; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • VISOBS
  • 15
  • POMD
  • 7
  • 2
  • Liquid-liquid equilibrium temperature, K ; Liquid mixture 1
  • Mole fraction - 2; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • VISOBS
  • 15
  • POMD
  • 10
  • 2
  • Liquid-liquid equilibrium temperature, K ; Liquid mixture 1
  • Mole fraction - 2; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • VISOBS
  • 15
  • POMD
  • 11
  • 2
  • Liquid-liquid equilibrium temperature, K ; Liquid mixture 1
  • Mole fraction - 2; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • VISOBS
  • 13
  • POMD
  • 12
  • 2
  • Liquid-liquid equilibrium temperature, K ; Liquid mixture 1
  • Mole fraction - 2; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • VISOBS
  • 12
  • POMD
  • 11
  • 3
  • Liquid-liquid equilibrium temperature, K ; Liquid mixture 1
  • Mole fraction - 3; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • VISOBS
  • 16
  • POMD
  • 12
  • 3
  • Liquid-liquid equilibrium temperature, K ; Liquid mixture 1
  • Mole fraction - 3; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • VISOBS
  • 14
  • POMD
  • 5
  • 1
  • Liquid-liquid equilibrium temperature, K ; Liquid mixture 1
  • Mole fraction - 1; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • VISOBS
  • 11
  • POMD
  • 7
  • 1
  • Liquid-liquid equilibrium temperature, K ; Liquid mixture 1
  • Mole fraction - 1; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • VISOBS
  • 19
  • POMD
  • 6
  • 1
  • Liquid-liquid equilibrium temperature, K ; Liquid mixture 1
  • Mole fraction - 1; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • VISOBS
  • 19
  • POMD
  • 8
  • 1
  • Liquid-liquid equilibrium temperature, K ; Liquid mixture 1
  • Mole fraction - 1; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • VISOBS
  • 17
  • POMD
  • 9
  • 1
  • Liquid-liquid equilibrium temperature, K ; Liquid mixture 1
  • Mole fraction - 1; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • VISOBS
  • 20
  • POMD
  • 11
  • 1
  • Liquid-liquid equilibrium temperature, K ; Liquid mixture 1
  • Mole fraction - 1; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • VISOBS
  • 9