Thermodynamics Research Center / ThermoML | Fluid Phase Equilibria

Phase equilibrium for ternary liquid systems of water + di-(2- ethylhexyl)phosphoric acid + organic diluents: Thermodynamic study

Srirachat, W.[Wanchalerm], Wongsawa, T.[Thidarat], Sunsandee, N.[Niti], Pancharoen, U.[Ura], Kheawhom, S.[Soorathep]
Fluid Phase Equilib. 2015, 401, 34-47
ABSTRACT
The influences of temperature on equilibrium solubility for the ternary liquid systems of water + di-(2- ethylhexyl)phosphoric acid + organic diluents were investigated by cloud point titration at T = 303.2 333.2 K and atmospheric pressure. Various organic diluents having different dielectric constants of kerosene (n/a), n-heptane (1.9), chlorobenzene (5.6) and 1-octanol (10.3) were designated to observe the polar influence on the solubility. All ternary systems exhibited the type II behavior, and their solubility increased with the polarity and studied temperatures. The tie-line data for each ternary liquid system were also studied and correlated by the Bachman plots. Moreover, the experimental solubility of water in the organic phases were predicted using the modified Apelblat equation, and the results were validated by the relative average deviation (RAD) as shown in a range of 0.01 4.09%. The dissolution thermodynamics of water in the organic phases were studied using the van t Hoff model in order to determine its enthalpy (DHd), entropy (DSd) and Gibbs energy (DGd). The results indicated that the dissolution of water in the organic phases was endothermic and a non-spontaneous process and driven by entropy.
Compounds
# Formula Name
1 C7H16 heptane
2 C16H35O4P bis(2-ethylhexyl) hydrogen phosphate
3 H2O water
4 C6H5Cl chlorobenzene
5 C8H18O octan-1-ol
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
  • 3
  • Mass fraction - 2 ; 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
  • 52
  • POMD
  • 1
  • 2
  • 3
  • Mass fraction - 3 ; Liquid mixture 1
  • Mass fraction - 2 ; Liquid mixture 2
  • Mass fraction - 3 ; Liquid mixture 2
  • Temperature, K; Liquid mixture 2
  • Mass fraction - 2; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 2
  • Liquid mixture 1
  • Liquid mixture 2
  • Titration method
  • Titration method
  • Titration method
  • 16
  • POMD
  • 4
  • 2
  • 3
  • Mass fraction - 2 ; 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
  • 52
  • POMD
  • 4
  • 2
  • 3
  • Mass fraction - 2 ; Liquid mixture 2
  • Mass fraction - 3 ; Liquid mixture 1
  • Mass fraction - 2 ; Liquid mixture 1
  • Temperature, K; Liquid mixture 1
  • Mass fraction - 3; Liquid mixture 2
  • Pressure, kPa; Liquid mixture 2
  • Liquid mixture 2
  • Liquid mixture 1
  • Titration method
  • Titration method
  • Titration method
  • 16
  • POMD
  • 5
  • 2
  • 3
  • Mass fraction - 2 ; 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
  • 52
  • POMD
  • 5
  • 2
  • 3
  • Mass fraction - 3 ; Liquid mixture 2
  • Mass fraction - 3 ; Liquid mixture 1
  • Mass fraction - 2 ; Liquid mixture 1
  • Temperature, K; Liquid mixture 1
  • Mass fraction - 2; Liquid mixture 2
  • Pressure, kPa; Liquid mixture 2
  • Liquid mixture 2
  • Liquid mixture 1
  • Titration method
  • Titration method
  • Titration method
  • 16
  • 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
  • Titration method
  • 8
  • POMD
  • 2
  • 3
  • Mass fraction - 2 ; Liquid mixture 1
  • Temperature, K; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • Titration method
  • 7
  • POMD
  • 4
  • 3
  • Mass fraction - 3 ; Liquid mixture 1
  • Temperature, K; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • Titration method
  • 8
  • POMD
  • 5
  • 3
  • Mass fraction - 3 ; Liquid mixture 1
  • Temperature, K; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • Titration method
  • 8