Comparative study of mixing rules for cubic equations of state in the prediction of multicomponent vapor-liquid equilibria

Some common volume-independent mixing rules and the problems associated with them are reviewed. Reported experimental data of a highly non-ideal quaternary mixture and all its constituent binaries and ternaries are used for adjusting binary interaction parameters and comparing the performance of each mixing rule in predicting vapor-liquid equilibria (VLE). The parameters in each mixing rule were obtained fitting experimental binary data only. The ternary and quaternary VLE calculations were then used to test the capability of the mixing rules to predict multicomponent VLE. It is shown that the VLE of those systems can be adequately reproduced with a cubic equation of state using Wong and Sandler's mixing rule with Wilson's excess Gibbs energy function thanks to its simultaneous correction of several inconveniences. It is also shown that mixing rules should be tested with multicomponent mixtures.

[1]  J. Vera,et al.  PRSV: The stryjek‐vera modification of the peng‐robinson equation of state. Parameters for other pure compounds of industrial interest , 1989 .

[2]  J. Vera,et al.  Prediction of ternary vapor-liquid equilibria with the PRSV equation of state , 1989 .

[3]  Y. Adachi,et al.  A new mixing rule—modified conventional mixing rule , 1986 .

[4]  J. Gmehling.  Vapor-Liquid Equilibrium Data Collection , 1977 .

[5]  Rajat Saini,et al.  A modified Peng-Robinson equation of state , 1989, Fluid Phase Equilibria.

[6]  R. Reid,et al.  Multiphase high pressure equilibria in ternary aqueous systems , 1986 .

[7]  R. Reid,et al.  The Properties of Gases and Liquids , 1977 .

[8]  Michael L. Michelsen,et al.  On composition-dependent interaction coefficeints , 1990 .

[9]  K. Kojima,et al.  Mixing rule containing regular-solution and residual excess free energy. , 1987 .

[10]  R. Stryjek,et al.  “PRSV — An improved peng‐robinson equation of state with new mixing rules for strongly nonideal mixtures” , 1986 .

[11]  J. Smith,et al.  Introduction to chemical engineering thermodynamics , 1949 .

[12]  Paul M. Mathias,et al.  Equation-of-State mixing rules for multicomponent mixtures: the problem of invariance , 1991 .

[13]  M. Huron,et al.  New mixing rules in simple equations of state for representing vapour-liquid equilibria of strongly non-ideal mixtures☆ , 1979 .

[14]  H. Renon,et al.  Equations of state: how to reconcile flexible mixing rules, the virial coefficient constraint and the “michelsen-Kistenmacher syndrome” for multicomponent systems , 1991 .

[15]  R. Stryjek,et al.  PRSV: An improved peng—Robinson equation of state for pure compounds and mixtures , 1986 .

[16]  David Shan-Hill Wong,et al.  A theoretically correct mixing rule for cubic equations of state , 1992 .

[17]  S. Sandler,et al.  Critical evaluation of equation of state mixing rules for the prediction of high-pressure phase equilibria , 1989 .