Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

Liquid Liquid Equilibria of Quaternary Systems Composed of 1,3-Propanediol, Short-Chain Alcohol, Water, and Salt

Gerlach, T.[Thomas], Smirnova, I.[Irina]
J. Chem. Eng. Data 2016, 61, 10, 3548-3558
ABSTRACT
In different fermentation processes the separation of the products from aqueous solution is an energy-intensive process step, particularly for hydrophilic products like diols. As an alternative to evaporation and distillation, liquid liquid extraction of these products is often limited by the unfavorable partition behavior of the diols. In this work phase equilibria for four quaternary systems consisting of water, 1,3-propanediol, a salt (K2HPO4, K2CO3, or Na2CO3), and a short-chain alcohol (ethanol, 1-propanol, or 2-propanol) were investigated. For all investigated systems favorable partitioning behavior of the hydrophilic diol into the organic phase was found. The partition ratio of the diol depends strongly on the salt content of the system. In the region of salt mass fractions in the salt-rich phase lower than 30 wt % highest partition ratios as well as highest selectivities were reached with systems of the type Na2CO3 + H2O + 1-propanol/2-propanol + water. Furthermore, the predictive thermodynamic model COSMO-RS was used with an electrolyte extension for the prediction of the partition ratio of the diol at infinite dilution in the 1,3-propanediol free systems. The partition ratio was overestimated by the model. Nevertheless, a qualitative agreement concerning the order of the partition ratio was reached at lower salt contents, and the increase in the partition coefficient with an increasing mass fraction of the salt was predicted for all systems except for the K2CO3 + H2O + ethanol system at high salt mass fractions.
Compounds
# Formula Name
1 C2H6O ethanol
2 C3H8O propan-1-ol
3 HK2O4P dipotassium hydrogen phosphate
4 CNa2O3 sodium carbonate
5 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
  • 5
  • 3
  • Mass fraction - 3 ; Liquid mixture 1
  • Mass fraction - 3 ; Liquid mixture 2
  • Mass fraction - 5 ; Liquid mixture 2
  • Mass fraction - 5; Liquid mixture 1
  • Temperature, K; Liquid mixture 2
  • Pressure, kPa; Liquid mixture 2
  • Liquid mixture 1
  • Liquid mixture 2
  • OTHER
  • OTHER
  • OTHER
  • 6
  • POMD
  • 2
  • 4
  • 5
  • Mass fraction - 5 ; Liquid mixture 1
  • Mass fraction - 4 ; Liquid mixture 2
  • Mass fraction - 5 ; Liquid mixture 2
  • Mass fraction - 4; Liquid mixture 1
  • Temperature, K; Liquid mixture 2
  • Pressure, kPa; Liquid mixture 2
  • Liquid mixture 1
  • Liquid mixture 2
  • OTHER
  • OTHER
  • OTHER
  • 6