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A Modified Local Composition-Based Model for Correlating the Vapor-Liquid and Liquid-Liquid Phase Equilibria of Aqueous Polymer-Salt Systems

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Abstract

In this research, a new local composition model has been proposed to study the vapor-liquid and liquid-liquid phase equilibria of polyelectrolyte solutions. The proposed model has been used in order to obtain the activity of water in polyethylene glycol (PEG) and polypropylene glycol (PPG) solutions. The interaction parameters introduced into the proposed model have been reported. The interaction parameters between the salt and water molecule have been estimated using the experimental mean ionic activity coefficients of aqueous electrolytes studied in this work. Also, the interaction parameters between the polymer and salt molecule, and the polymer and water molecule have been computed using the experimental activity of water data in aqueous polymer solutions. The results showed that the proposed model, segment-based Wilson and segment-based NRTL models have good accuracy in correlating the vapor-liquid phase equilibria of the water-polymer and water-polymer-salt systems.

Also, the liquid-liquid phase behavior of the polymer-salt aqueous two-phase systems has been correlated using the proposed model. The results show that the proposed model can more accurately correlate the phase behavior of aqueous two-phase systems than the UNIQUAC and the modified Wilson models.

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References

  1. Albertsson, P.A.: Partition of Cell Particles and Macromolecules. Wiley, New York (1986)

    Google Scholar 

  2. Hustedt, H., Kroner, K.H., Kula, M.R.: Application of phase partitioning in biotechnology. In: Walter, H., Brooks, D., Fisher, D. (eds.) Partitioning in Aqueous Two-phase Systems. Theory, Methods, Uses and Applications to Biotechnology. Academic Press, London (1985)

    Google Scholar 

  3. Zaslavsky, B.Y.: Aqueous Two-phase Partitioning. Marcel Dekker, New York (1995)

    Google Scholar 

  4. Edmond, E., Ogston, P.G.: An approach to the study of the of phase separation in ternary aqueous systems. Biochem. J. 109, 569–576 (1968)

    CAS  Google Scholar 

  5. Peng, Q., Li, Z., Li, Y.: Application of regular solution theory to calculation of liquid-liquid equilibria for water-containing systems. Fluid Phase Equilib. 97, 67–80 (1994)

    Article  CAS  Google Scholar 

  6. Kang, C.H., Sandler, S.I.: Phase behavior of aqueous two-polymer systems. Fluid Phase Equilib. 38, 245–272 (1987)

    Article  CAS  Google Scholar 

  7. Kang, C.H., Sandler, S.I.: A thermodynamic model for two-phase aqueous polymer systems. Biotech. Bioeng. 32, 1158–1164 (1988)

    Article  CAS  Google Scholar 

  8. Kabiri-Badr, M., Cabezas, H. Jr.: A thermodynamic model for the phase behavior of salt-polymer aqueous two-phase systems. Fluid Phase Equilib. 115, 39–58 (1996)

    Article  CAS  Google Scholar 

  9. Wu, Y.T., Lin, D.Q., Zhu, Z.Q.: Thermodynamics of aqueous two-phase systems- the effect of polymer molecular weight on liquid-liquid equilibrium phase diagrams by the modified NRTL model. Fluid Phase Equilib. 147, 25–43 (1998)

    Article  CAS  Google Scholar 

  10. Madeira, P.P., Xu, X., Wu, Y.T., Teixeira, J.A., Macedo, E.A.: Liquid-liquid equilibrium of aqueous polymer two-phase systems using the modified Wilson equation. Ind. Eng. Chem. Res. 44, 2328–2332 (2005)

    Article  CAS  Google Scholar 

  11. Xu, X., Madeira, P.P., Macedo, E.A.: Representation of liquid-liquid equilibria for polymer-salt aqueous two-phase systems. Chem. Eng. Sci. 59, 1153–1159 (2004)

    Article  CAS  Google Scholar 

  12. Sadeghi, R.: Extension of the Wilson model to multicomponent polymer solutions: applications to polymer-polymer aqueous two-phase systems. J. Chem. Thermodyn. 37, 55–60 (2005)

    Article  CAS  Google Scholar 

  13. Sadeghi, R.: A modified Wilson model for the calculation of vapor + liquid equilibrium of aqueous polymer + salt solutions. J. Chem. Thermodyn. 37, 327–333 (2005)

    Google Scholar 

  14. Kabiri-Badr, M.: Thermodynamics of salt + polymer aqueous two-phase systems: theory and experiment. Ph.D. Thesis, The University of Arizona, USA (1990)

  15. Grossmann, C., Trintinger, R., Zhu, J., Maurer, G.: Partitioning of some amino acids and low molecular peptides in aqueous two-phase systems of poly (ethylene glycol) and dipotassium hydrogen phosphate. Fluid Phase Equilib. 137, 209–228 (1997)

    Article  CAS  Google Scholar 

  16. Gaube, J., Pfenning, A., Stumpf, M.: Thermodynamics of aqueous poly(ethylene glycol)-dextran two-phase systems using the consistent osmotic virial equation. Fluid Phase Equilib. 83, 365–373 (1993)

    Article  CAS  Google Scholar 

  17. Wu, Y.T., Lin, D.Q., Zhu, Z.Q., Mei, L.H.: Prediction of liquid-liquid equilibria of polymer—salt aqueous two-phase systems by a modified Pitzer’s equation. Fluid Phase Equilib. 124, 67–79 (1996)

    Article  CAS  Google Scholar 

  18. Gao, Y.L., Peng, Q.H., Li, Z.C., Li, Y.G.: Thermodynamics of ammonium sulfate-polyethylene glycol aqueous two-phase systems. Part 1. Experimental and correlation using extended UNIQUAC equation. Fluid Phase Equilib. 63, 157–171 (1995)

    Article  Google Scholar 

  19. Gao, Y.L., Peng, Q.H., Li, Z.C., Li, Y.G.: Thermodynamics of ammonium sulfate-polyethylene glycol aqueous two-phase systems. Part 2. Correlation and prediction using extended UNIFAC equation. Fluid Phase Equilib. 63, 173–182 (1991)

    Article  CAS  Google Scholar 

  20. Nakanishi, K., Tanaka, H.: Molecular dynamic studies on the local composition in Lennard-Jones liquid mixtures of non-spherical molecules. Fluid Phase Equilib. 13, 371–380 (1983)

    Article  CAS  Google Scholar 

  21. Wilson, G.M.: Vapor-liquid equilibrium. XI: a new expression for the excess free energy of mixing. J. Am. Chem. Soc. 86, 127–130 (1964)

    Article  CAS  Google Scholar 

  22. Renon, H., Prausnitz, J.M.: Local composition in thermodynamic excess function for liquid mixtures. AIChE J. 14, 135–144 (1968)

    Article  CAS  Google Scholar 

  23. Wu, D.W., Gui, Y., Donohue, M.D.: Local composition models for lattice mixtures. Ind. Eng. Chem. Res. 37, 2936–2949 (1998)

    Article  CAS  Google Scholar 

  24. Ruckenstein, E., Shulgin, I.: Modified local composition and Flory-Huggins equations for nonelectrolyte solutions. Ind. Eng. Chem. Res. 38, 4092–4099 (1999)

    Article  CAS  Google Scholar 

  25. Smith, J.M., Van Ness, H.C., Abbott, M.M.: Introduction to Chemical Engineering Thermodynamics. McGraw-Hill, Boston (2001)

    Google Scholar 

  26. Ninni, L., Camargo, M.S., Meirelles, A.J.A.: Water activity in poly (ethylene glycol) aqueous solutions. Thermochim. Acta 328, 169–176 (1999)

    Article  CAS  Google Scholar 

  27. Lin, D.Q., Zhu, Z.Q., Mei, L.H., Yang, L.R.: Isopiestic determination of the water activities of poly (ethylene glycol) + salt + water systems at 25 °C. J. Chem. Eng. Data 41, 1040–1042 (1996)

    Article  CAS  Google Scholar 

  28. Lin, D.Q., Mei, L.H., Zhu, Z.Q., Han, Z.X.: An improved isopiestic method for measurement of water activities in aqueous polymer and salt solutions. Fluid Phase Equilib. 118, 241–248 (1996)

    Article  CAS  Google Scholar 

  29. Zafarani-Moattar, M.T., Salabat, A.: Measurement and correlation of viscosities, densities and water activities for the system poly (ethylene glycol) + MgSO4 + water at 25 °C. J. Solution Chem. 27, 663–673 (1998)

    Article  CAS  Google Scholar 

  30. Salabat, A., Dashti, H., Nasirzadeh, K.: Measurement and correlation of water activities and refractive indexes for the systems PPG425 + (NH4)2SO4 + H2O and PPG425 + Na2SO4 + H2O at 298.15 K. J. Chem. Eng. Data 49, 980–982 (2004)

    Article  CAS  Google Scholar 

  31. Sadeghi, R.: A modified segment-based nonrandom two-liquid model for the calculation of vapor-liquid equilibrium of aqueous polymer-salt solutions. Chem. Eng. Sci. 61, 7786–7794 (2006)

    Article  CAS  Google Scholar 

  32. Pazuki, G.R., Taghikhani, V., Vossoughi, M.: Correlation and prediction the activity coefficients and solubility of amino acids and simple peptides in aqueous solution using the modified local composition model. Fluid Phase Equilib. 225, 160–166 (2007)

    Article  Google Scholar 

  33. Pazuki, G.R., Rohani, A.A.: A new model for the activity coefficients of individual ions in aqueous electrolyte solutions. Fluid Phase Equilib. 242, 65–71 (2006)

    Article  CAS  Google Scholar 

  34. Pazuki, G.R., Arabgol, F.: A new model for predicting the thermodynamic phase behavior of electrolyte in aqueous solutions. CALPHAD 29, 125–132 (2005)

    Article  CAS  Google Scholar 

  35. Robinson, R.A., Stokes, R.H.: Electrolyte Solutions. Butterworth, London (1970)

    Google Scholar 

  36. Chen, C.C., Britt, H.I., Boston, J.F., Evans, L.B.: Local composition model for excess Gibbs energy of electrolyte systems. Part 1: Single solvent, single completely dissociated electrolyte systems. AIChE J. 28, 588–596 (1982)

    Article  CAS  Google Scholar 

  37. Zhao, E., Yu, M., Sauve, R.E., Khsohkbarchi, M.K.: Extension of the Wilson model to the electrolyte solutions. Fluid Phase Equilib. 173, 161–175 (2000)

    Article  CAS  Google Scholar 

  38. Salabat, A., Nasirzadeh, K.: Measurement and prediction of water activity in PEG + (NH4)2SO4 + H2O systems using polymer scaling laws. J. Mol. Liq. 103–104, 349–358 (2003)

    Article  Google Scholar 

  39. Ochs, L.R., Kabiri-Badr, M., Cabezas, H.: An improved isopiestic method to determine activities in multi-component mixtures. AIChE J. 36, 1908–1912 (1990)

    Article  CAS  Google Scholar 

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Authors and Affiliations

  1. Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran

    Gholam Reza Pazuki, Vahid Taghikhani & Manuchehr Vossoughi

  2. Institute for Nano-science and Nano-technology, Sharif University of Technology, Tehran, Iran

    Manuchehr Vossoughi

Authors
  1. Gholam Reza Pazuki
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  2. Vahid Taghikhani
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  3. Manuchehr Vossoughi
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Correspondence to Manuchehr Vossoughi.

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Pazuki, G.R., Taghikhani, V. & Vossoughi, M. A Modified Local Composition-Based Model for Correlating the Vapor-Liquid and Liquid-Liquid Phase Equilibria of Aqueous Polymer-Salt Systems. J Solution Chem 37, 665–675 (2008). https://doi.org/10.1007/s10953-008-9259-1

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  • DOI: https://doi.org/10.1007/s10953-008-9259-1

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