Skip to main content
Log in

The Thermodynamic Properties of Non-Associating and Associating Fluids: A Systematic Evaluation of SAFT-Type Equations of State

  • Published:
International Journal of Thermophysics Aims and scope Submit manuscript

Abstract

Statistical Associating Fluid Theory (SAFT) equations of state (EoSs) have been extensively used for estimating thermodynamic properties of fluids. However, the predicted performance of SAFT-type EoSs for associating and non-associating fluids under the same thermodynamic conditions is poorly understood. In this work, four typical SAFT-type EoSs including the CPA, CK-SAFT, PC-SAFT, and SAFT-VR Mie EoSs are mainly employed and then a systematic evaluation is performed for the phase equilibria and derivative properties of the common non-associating (alkanes and carbon dioxide) and associating fluids (methanol and water). The results show that the misdescription of the residual Helmholtz free energy by SAFT-type EoSs is the major cause for the prediction accuracy of vapor–liquid equilibria (VLE). SAFT-VR Mie outperforms the others when predicting VLE of all the considered compounds, especially in conditions near the critical point, with an average absolute relative deviation (AARD) below 0.5%. PC-SAFT provides satisfactory enthalpy of vaporization (ΔHv) predictions of alkanes, but its performance is inferior to PR due to the inaccurate description of the liquid-phase ∂A/∂T derivatives. Adopting a reasonable association scheme or including the ΔHv experimental data into the parameter regression routine can effectively improve the predictions accuracy of ΔHv for associating fluids. Overall, SAFT-VR Mie performs the best performance in correlating isobaric heat capacity (CP) due to the improved description of the ∂2A/∂VT and ∂2A/∂V2 derivatives. Re-optimizing the universal constants of the dispersion term or employing higher-order perturbations can effectively improve the CP predictions.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12

Similar content being viewed by others

Availability of Data and Materials

All data used are transparent.

Abbreviations

AARD:

Average absolute relative deviation

CEoSs:

Cubic equations of state

CK-SAFT:

Chen and Kreglewski-SAFT

CPA:

Cubic-Plus-Association

EoSs:

Equations of state

NBP:

Normal boiling point

PC-SAFT:

Perturbed Chain-SAFT

PR:

Peng–Robinson

RK:

Redlich–Kwong

SAFT:

Statistical associating fluid theory

SAFT-VR Mie:

SAFT-Variable Range Mie

SRK:

Soave–Redlich–Kwong

vdW:

Van der Waals

VLE:

Vapor–liquid equilibria

A:

Helmholtz free energy, J·mol1

CP :

Isobaric heat capacity, J·mol1·K1

N:

Number of data points

P:

Pressure, Pa

Ps :

Saturated pressure, Pa

R:

Universal gas constant, J·mol1·K1

T:

Temperature, K

V:

Volume, m3·mol1

X:

Property used to calculate AARD in Eq. 6

XA i :

Fraction of A sites of molecule i that are not bonded

Z:

Compressibility factor

ρs :

Saturated liquid density, mol·m3

ΔHv :

Enthalpy of vaporization, J·mol1

a:

Energy parameter of cubic equations of state

b:

Co-volume parameter of cubic equations of state

g:

Radial distribution function

h:

Enthalpy, J·mol1

k:

Boltzmann’s constant, J·K1

m:

Segment number

ε :

Depth of pair potential, J

η :

Packing fraction

ρ :

Number density

σ :

Segment diameter, Å

ω :

Acentric factor

assoc:

Association contribution

c:

Critical

calc:

Calculated property

chain:

Contribution due to the formation of chains

disp:

Contribution due to the dispersive attraction

exp:

Experimental property

hs:

Contribution of hard-sphere system

i, j:

Component indexes

ideal:

Ideal gas contribution

mono:

Contribution of monomer system

pert:

Perturbed

r:

Reduced

ref:

Reference

res:

Residual

References

  1. J. Ma, J. Li, C. He, C. Peng, H. Liu, Y. Hu, Thermodynamic properties and vapor–liquid equilibria of associating fluids, Peng-Robinson equation of state coupled with shield-sticky model. Fluid Phase Equilib. 330, 1–11 (2012)

    Article  Google Scholar 

  2. F. Yang, Q. Liu, Y. Duan, Z. Yang, Crossover multiparameter equation of state: general procedure and demonstration with carbon dioxide. Fluid Phase Equilib. 494, 161–171 (2019)

    Article  Google Scholar 

  3. S. Sathish, P. Kumar, Equation of state based analytical formulation for optimization of sCO2 Brayton cycle. J. Supercrit. Fluids 177, 105351 (2021)

    Article  Google Scholar 

  4. de Hemptinne J-C, Kontogeorgis GM, Dohrn R, Economou IG, ten Kate A, Kuitunen S, et al. A View on the Future of Applied Thermodynamics. Ind. Eng. Chem. Res. 2022.

  5. Ø. Wilhelmsen, A. Aasen, G. Skaugen, P. Aursand, A. Austegard, E. Aursand et al., Thermodynamic modeling with equations of state: present challenges with established methods. Ind. Eng. Chem. Res. 56, 3503–3515 (2017)

    Article  Google Scholar 

  6. O. Redlich, J.N.S. Kwong, On the thermodynamics of solutions v an equation of state fugacities of gaseous solutions. Chem. Rev. 44, 233–244 (1949)

    Article  Google Scholar 

  7. D.-Y. Peng, D.B. Robinson, A New Two-Constant Equation of State. Ind. Eng. Chem. Fundam. 15, 59–64 (1976)

    Article  Google Scholar 

  8. G. Soave, Equilibrium constants from a modified Redlich-Kwong equation of state. Chem. Eng. Sci. 27, 1197–1203 (1972)

    Article  Google Scholar 

  9. G.M. Kontogeorgis, G.K. Folas, Thermodynamic models for industrial applications : from classical and advanced mixing rules to association theories (Wiley, UK, 2010)

    Book  Google Scholar 

  10. J. Greogorowicz, J.P. O’Connell, C.J. Peters, Some characteristics of pure fluid properties that challenge equation-of-state models. Fluid Phase Equilib. 116, 94–101 (1996)

    Article  Google Scholar 

  11. N.I. Diamantonis, G.C. Boulougouris, E. Mansoor, D.M. Tsangaris, I.G. Economou, Evaluation of cubic, SAFT, and PC-SAFT equations of state for the vapor-liquid equilibrium modeling of CO2 Mixtures with Other Gases. Ind. Eng. Chem. Res. 52, 3933–3942 (2013)

    Article  Google Scholar 

  12. M.A. Marcelino Neto, J.R. Barbosa, Prediction of refrigerant-lubricant viscosity using the general PC-SAFT friction theory. Int. J. Refrig 45, 92–99 (2014)

    Article  Google Scholar 

  13. A.M.A. Dias, J.C. Pàmies, J.A.P. Coutinho, I.M. Marrucho, L.F. Vega, SAFT Modeling of the solubility of gases in perfluoroalkanes. J. Phys. Chem. B 108, 1450–1457 (2004)

    Article  Google Scholar 

  14. G.M. Kontogeorgis, E.C. Voutsas, I.V. Yakoumis, D.P. Tassios, An Equation of state for associating fluids. Ind. Eng. Chem. Res. 35, 4310–4318 (1996)

    Article  Google Scholar 

  15. W.G. Chapman, K.E. Gubbins, G. Jackson, M. Radosz, SAFT: Equation-of-state solution model for associating fluids. Fluid Phase Equilib. 52, 31–38 (1989)

    Article  Google Scholar 

  16. S.H. Huang, M. Radosz, Equation of state for small, large, polydisperse, and associating molecules. Ind. Eng. Chem. Res. 29, 2284–2294 (1990)

    Article  Google Scholar 

  17. J. Gross, G. Sadowski, Perturbed-chain SAFT: an equation of state based on a perturbation theory for chain molecules. Ind. Eng. Chem. Res. 40, 1244–1260 (2001)

    Article  Google Scholar 

  18. T. Lafitte, A. Apostolakou, C. Avendaño, A. Galindo, C.S. Adjiman, E.A. Müller et al., Accurate statistical associating fluid theory for chain molecules formed from Mie segments. J. Chem. Phys. 139, 154504–154540 (2013)

    Article  ADS  Google Scholar 

  19. J. Bao, L. Zhao, A review of working fluid and expander selections for organic Rankine cycle. Renew. Sustain. Energy Rev. 24, 325–342 (2013)

    Article  Google Scholar 

  20. M.-J. Li, H.-H. Zhu, J.-Q. Guo, K. Wang, W.-Q. Tao, The development technology and applications of supercritical CO2 power cycle in nuclear energy, solar energy and other energy industries. Appl. Therm. Eng. 126, 255–275 (2017)

    Article  Google Scholar 

  21. V.R. Surisetty, A.K. Dalai, J. Kozinski, Alcohols as alternative fuels: An overview. Appl. Catal. A: Gen 404, 1–11 (2011)

    Google Scholar 

  22. H. Quinteros-Lama, F. Llovell, Global phase behaviour in methane plus n-alkanes binary mixtures. J Supercrit. Fluids. 111, 151–161 (2016)

    Article  Google Scholar 

  23. G.K. Folas, J. Gabrielsen, M.L. Michelsen, E.H. Stenby, G.M. Kontogeorgis, Application of the Cubic-Plus-Association (CPA) equation of state to cross-associating systems. Ind. Eng. Chem. Res. 44, 3823–3833 (2005)

    Article  Google Scholar 

  24. M.B. Oliveira, I.M. Marrucho, J.A.P. Coutinho, A.J. Queimada, Surface tension of chain molecules through a combination of the gradient theory with the CPA EoS. Fluid Phase Equilib. 267, 83–91 (2008)

    Article  Google Scholar 

  25. I. Tsivintzelis, G.M. Kontogeorgis, M.L. Michelsen, E.H. Stenby, Modeling phase equilibria for acid gas mixtures using the CPA equation of state I Mixtures with H2S. AIChE J. 56, 2965–2982 (2010)

    Article  Google Scholar 

  26. P.C.V. Tybjerg, G.M. Kontogeorgis, M.L. Michelsen, E.H. Stenby, Phase equilibria modeling of methanol-containing systems with the CPA and sPC-SAFT equations of state. Fluid Phase Equilib. 288, 128–138 (2010)

    Article  Google Scholar 

  27. M.B. Oliveira, A.J. Queimada, G.M. Kontogeorgis, J.A.P. Coutinho, Evaluation of the CO2 behavior in binary mixtures with alkanes, alcohols, acids and esters using the Cubic-Plus-Association Equation of State. J. Supercrit. Fluids. 55, 876–892 (2011)

    Article  Google Scholar 

  28. I. Tsivintzelis, G.M. Kontogeorgis, M.L. Michelsen, E.H. Stenby, Modeling phase equilibria for acid gas mixtures using the CPA equation of state. Part II: Binary mixtures with CO2. Fluid Phase Equilib. 306, 38–56 (2011)

    Article  Google Scholar 

  29. A.J. de Villiers, C.E. Schwarz, A.J. Burger, G.M. Kontogeorgis, Evaluation of the PC-SAFT, SAFT and CPA equations of state in predicting derivative properties of selected non-polar and hydrogen-bonding compounds. Fluid Phase Equilib. 338, 1–15 (2013)

    Article  Google Scholar 

  30. X. Liang, I. Tsivintzelis, G.M. Kontogeorgis, Modeling water containing systems with the simplified PC-SAFT and CPA equations of state. Ind. Eng. Chem. Res. 53, 14493–14507 (2014)

    Article  Google Scholar 

  31. A.M. Palma, M.B. Oliveira, A.J. Queimada, J.A.P. Coutinho, Re-evaluating the CPA EoS for improving critical points and derivative properties description. Fluid Phase Equilib. 436, 85–97 (2017)

    Article  Google Scholar 

  32. C. Zhu, X. Liu, M. He, G.M. Kontogeorgis, X. Liang, Heat capacities of fluids: the performance of various equations of state. J. Chem. Eng. Data 65, 5654–5676 (2020)

    Article  Google Scholar 

  33. M.G. Bjørner, G.M. Kontogeorgis, Modeling derivative properties and binary mixtures with CO2 using the CPA and the quadrupolar CPA equations of state. Fluid Phase Equilib. 408, 151–169 (2016)

    Article  Google Scholar 

  34. M. Yarrison, W.G. Chapman, A systematic study of methanol+n-alkane vapor–liquid and liquid–liquid equilibria using the CK-SAFT and PC-SAFT equations of state. Fluid Phase Equilib. 226, 195–205 (2004)

    Article  Google Scholar 

  35. M. Yang, T. Zhan, Y. Su, A. Dong, M. He, Y. Zhang, Crossover PC-SAFT equations of state based on White’s method for the thermodynamic properties of CO2, n-alkanes and n-alkanols. Fluid Phase Equilib. 564, 113610 (2023)

    Article  Google Scholar 

  36. A.H. Tafazzol, K. Nasrifar, Thermophysical properties of associating fluids in natural gas industry using PC-SAFT equation of state. Chem. Eng. Commun. 198, 1244–1262 (2011)

    Article  Google Scholar 

  37. S. Dufal, T. Lafitte, A. Galindo, G. Jackson, A.J. Haslam, Developing intermolecular-potential models for use with the SAFT-VR Mie equation of state. AIChE J. 61, 2891–2912 (2015)

    Article  Google Scholar 

  38. P.D. Ting, P.C. Joyce, P.K. Jog, W.G. Chapman, M.C. Thies, Phase equilibrium modeling of mixtures of long-chain and short-chain alkanes using Peng-Robinson and SAFT. Fluid Phase Equilib. 206, 267–286 (2003)

    Article  Google Scholar 

  39. A. Jamali, H. Behnejad, Observations regarding the first and second order thermodynamic derivative properties of non-polar and light polar fluids by perturbed chain-SAFT equations of state. Cryogenics 99, 78–86 (2019)

    Article  ADS  Google Scholar 

  40. J. Gross, G. Sadowski, Application of the perturbed-chain SAFT equation of state to associating systems. Ind. Eng. Chem. Res. 41, 5510–5515 (2002)

    Article  Google Scholar 

  41. X. Liang, K. Thomsen, W. Yan, G.M. Kontogeorgis, Prediction of the vapor–liquid equilibria and speed of sound in binary systems of 1-alkanols and n-alkanes with the simplified PC-SAFT equation of state. Fluid Phase Equilib. 360, 222–232 (2013)

    Article  Google Scholar 

  42. K. Mejbri, A. Taieb, A. Bellagi, Phase equilibria calculation of binary and ternary mixtures of associating fluids applying PC-SAFT equation of state. J. Supercrit. Fluid. 104, 132–144 (2015)

    Article  Google Scholar 

  43. N.I. Diamantonis, I.G. Economou, Evaluation of Statistical Associating Fluid Theory (SAFT) and perturbed Chain-SAFT equations of state for the calculation of thermodynamic derivative properties of fluids related to carbon capture and sequestration. Energy Fuels 25, 3334–3343 (2011)

    Article  Google Scholar 

  44. S.A. Smith, J.T. Cripwell, C.E. Schwarz, A quadrupolar SAFT-VR mie approach to modeling binary mixtures of CO2 or benzene with n-Alkanes or 1-Alkanols. J. Chem. Eng. Data 65, 5778–5800 (2020)

    Article  Google Scholar 

  45. J.T. Cripwell, S.A.M. Smith, C.E. Schwarz, A.J. Burger, SAFT-VR mie: application to phase equilibria of alcohols in mixtures with n-Alkanes and Water. Ind. Eng. Chem. Res. 57, 9693–9706 (2018)

    Article  Google Scholar 

  46. E.W. Lemmon MLH, McLinden MO. NIST Standard Reference Database 23:Reference Fluid Thermodynamic and Transport Properties-REFPROP, Version 10.0; NIST:Gaithersburg, MD, 2013.

  47. I.V. Yakoumis, G.M. Kontogeorgis, E.C. Voutsas, D.P. Tassios, Vapor-liquid equilibria for alcoholhydrocarbon systems using the CPA Equation of state. Fluid Phase Equilib. 130, 31–47 (1997)

    Article  Google Scholar 

  48. S. Dufal, V. Papaioannou, M. Sadeqzadeh, T. Pogiatzis, A. Chremos, C.S. Adjiman et al., Prediction of thermodynamic properties and phase behavior of fluids and mixtures with the SAFT-γ mie group-contribution equation of state. J. Chem. Eng. Data 59, 3272–3288 (2014)

    Article  Google Scholar 

  49. G.M. Kontogeorgis, V.I. Yakoumis, H. Meijer, E. Hendriks, T. Moorwood, Multicomponent phase equilibrium calculations for water–methanol–alkane mixtures. Fluid Phase Equilib. 158–160, 201–209 (1999)

    Article  Google Scholar 

  50. S. Dufal, T. Lafitte, A.J. Haslam, A. Galindo, G.N.I. Clark, C. Vega et al., The A in SAFT: developing the contribution of association to the Helmholtz free energy within a Wertheim TPT1 treatment of generic Mie fluids. Mol. Phys. 113, 948–984 (2015)

    Article  ADS  Google Scholar 

  51. Y. Le Guennec, S. Lasala, R. Privat, J.-N. Jaubert, A consistency test for α-functions of cubic equations of state. Fluid Phase Equilib. 427, 513–538 (2016)

    Article  Google Scholar 

  52. T. Lafitte, M.M. Piñeiro, J.-L. Daridon, D. Bessières, A Comprehensive description of chemical association effects on second derivative properties of alcohols through a SAFT-VR approach. J. Phys. Chem. B 111, 3447–3461 (2007)

    Article  Google Scholar 

  53. I. Polishuk, Standardized Critical Point-Based Numerical solution of statistical association fluid theory parameters: the perturbed chain-statistical association fluid theory equation of state revisited. Ind. Eng. Chem. Res. 53, 14127–14141 (2014)

    Article  Google Scholar 

  54. G.M. Kontogeorgis, M.L. Michelsen, G.K. Folas, S. Derawi, N. von Solms, E.H. Stenby, Ten years with the CPA (Cubic-Plus-Association) equation of state. Part 2. cross-associating and multicomponent systems. Ind. Eng. Chem. Res. 45, 4869–4878 (2006)

    Article  Google Scholar 

  55. I. Polishuk, Till which pressures the fluid phase EOS models might stay reliable? J. Supercrit. Fluid. 58, 204–215 (2011)

    Article  Google Scholar 

Download references

Acknowledgements

Financial support from the National Natural Science Foundation of China under Grant No.51976040, Grant No. 51236002 and the Guangdong Special Support Program under Grants No 2017TX04N371 is gratefully acknowledged.

Funding

Financial support from the National Natural Science Foundation of China under Grant No.51976040, Grant No. 51236002 and the Guangdong Special Support Program under Grants No. 2017TX04N371 is gratefully acknowledged.

Author information

Authors and Affiliations

Authors

Contributions

Y.M. contributed to data curation; formal analysis; investigation; methodology; Software; writing of the original draft; and writing, reviewing, & editing of the manuscript. Z.Y. contributed to investigation; software; supervision; funding acquisition; and writing, reviewing, & editing of the manuscript. H.G. contributed to investigation and writing, reviewing, & editing of the manuscript. Y.C. contributed to investigation and writing, reviewing, & editing of the manuscript. S.M. contributed to investigation; supervision; funding acquisition; and writing, reviewing, & editing of the manuscript. X.L. contributed to investigation and writing, reviewing, & editing of the manuscript. J.C. contributed to investigation and writing, reviewing, & editing of the manuscript. Y.L. contributed to investigation and writing, reviewing, & editing of the manuscript.

Corresponding authors

Correspondence to Zhi Yang or Songping Mo.

Ethics declarations

Conflict of interest

The authors declare that they have no conflict of interest

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Mao, Y., Yang, Z., Guo, H. et al. The Thermodynamic Properties of Non-Associating and Associating Fluids: A Systematic Evaluation of SAFT-Type Equations of State. Int J Thermophys 44, 32 (2023). https://doi.org/10.1007/s10765-022-03131-9

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s10765-022-03131-9

Keywords

Navigation