Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

Measurement and modelling of water activity of aqueous poly(ethylene glycol) or poly(propylene glycol) + sodium potassium tartrate and corresponding binary salt solutions

Zafarani-Moattar, M. T.[Mohammed Taghi], Asadzadeh, B.[Behnaz], Alizadeh, F.[Fatemeh]
J. Chem. Thermodyn. 2016, 100, 177-184
ABSTRACT
Water activity values of ternary aqueous sodium potassium tartrate (Na-K Tar) + poly (ethylene glycol) or poly (propylene glycol) solutions were measured using the isopiestic method at T = 298.15 K. Also the water activity for corresponding binary aqueous sodium potassium tartrate (Na-K Tar) solutions was measured at T = (298.15, 308.15, 318.15) K. The obtained water activity values for binary aqueous sodium potassium tartrate (Na-K Tar) system were successfully fitted with the local composition and Pitzer models. The mean activity coefficients for the studied binary salt solutions have been calculated. The thermodynamic behaviour of aqueous {(Na-K Tar) + poly (ethylene glycol) or poly (propylene glycol)} solutions was discussed on basis of water, polymer and salt interactions.
Compounds
# Formula Name
1 C4H4KNaO6 potassium sodium (2R,3R)-2,3-dihydroxybutanedioate (1:1:1)
2 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
  • 2
  • (Relative) activity - 2 ; Liquid
  • Temperature, K; Liquid
  • Molality, mol/kg - 1; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Chemical equilibration / Heterogeneous equilibration
  • 63