Liquid–liquid–vapour equilibria in binary and quasi-binary systems of CHF₃ with n-alkanes, phenylalkanes and alkanols

Abstract

Liquid–liquid–vapour equilibria were determined experimentally for binary systems of trifluoromethane with n-alkanes, phenylalkanes and octanol, and for quasi-binary systems of trifluoromethane with mixtures of hexane and heptane. For the trifluoromethane+n-alkane family the coordinates of the tricritical point and the double critical endpoint were estimated by extrapolation from the location of the critical endpoints g(l₂=l₁) and (g=l₁)l₂ of the three-phase curves. It is found that in these families an increase in carbon number of the n-alkane leads to a transition from type II to type IV to type III fluid phase behaviour. The tricritical point is found at a carbon number of the n-alkane of 6.509 and the double critical endpoint at a carbon number of the n-alkane of 6.51. The system trifluoromethane+phenylpropane shows type II phase behaviour, and the systems trifluoromethane+phenylbutane, +phenylpentane and +phenyloctane show type III phase behaviour. The system trifluoromethane+octanol is a type II system.

References

1. J. S. Rowlinson and F. L. Swinton, Liquids and Liquid Mixtures, Butterworths, London, 3rd edn., 1982.
2. C. J. Peters, in Supercritical Fluids, Fundamentals for Application, ed. E. Kiran and J. M. H. Levelt Sengers, Kluwer, Dordrecht, 1994, p. 117.
3. P. H. van Konynenburg and R. L. Scott, Philos. Trans. R. Soc. London, Ser. A, 1980, 298, 495.
4. A. Bolz, U. K. Deiters, C. J. Peters and Th. W. de Loos, Pure Appl. Chem., 1998, 70, 2233.
5. A. Jangkamolkulchai, D. H. Lam and K. D. Luks, Fluid Phase Equilib., 1989, 50, 175.
6. E. Brunner, J. Chem. Thermodyn., 1988, 20, 273.
7. M. Wirths and G. M. Schneider, Fluid Phase Equilib., 1985, 15, 257.
8. Th. W. de Loos, W. Poot and J. de Swaan Arons, J. Chem. Thermodyn., 1989, 21, 113.
9. R. Enick, G. D. Holder and B. I. Morsi, Fluid Phase Equilib., 1985, 22, 209.
10. D. J. Fall and K. D. Luks, J. Chem. Eng. Data, 1985, 30, 276.
11. G. G. Baylé, PhD Thesis (in Dutch), Delft University of Technology, Delft, 1951.
12. J. L. Creek, C. M. Knobler and R. L. Scott, J. Chem. Phys., 1981, 74, 3489.
13. M. C. Goh, J. Specovius, R. L. Scott and C. M. Knobler, J. Chem. Phys., 1987, 86, 4120.
14. Th. W. de Loos and W. Poot, Int. J. Thermophys., 1998, 19, 637.
15. Th. W. de Loos, H. J. van der Kooi and P. L. Ott, J. Chem. Eng. Data, 1986, 34, 166.
16. D. Stamoulis, PhD Thesis, Delft University of Technology, Delft, 1994.
17. Y. C. Hou and J. J. Martin, AIChE J., 1959, 5, 125.
18. A. Diefenbacher, M. Crone and M. Türk, J. Chem. Thermodyn., 1998, 30, 481.
19. K. Ohgaki, S. Umezono and T. Katayama, J. Supercrit. Fluids, 1990, 3, 78.
20. R. B. Griffiths, J. Chem. Phys., 1974, 60, 195.
21. R. L. Scott, J. Chem. Phys., 1987, 86, 4106.
22. U. K. Im and F. Kurata, J. Chem. Eng. Data, 1971, 16, 412.
23. J. D. Hottovy, K. D. Luks and J. P. Kohn, J. Chem. Eng. Data., 1981, 26, 256.
24. J. D. Hottovy, J. P. Kohn and K. D. Luks, J. Chem. Eng. Data, 1982, 27, 298.
25. D. J. Fall, J. L. Fal and K. D. Lucks, J. Chem. Eng. Data, 1985, 30, 82.
26. D. H. Lam, A. Jangkamolkulchai and K. D. Luks, Fluid Phase Equilib., 1990, 60, 131.
27. D. H. Lam, A. Jangkamolkulchai and K. D. Luks, Fluid Phase Equilib., 1990, 60, 119.
28. S. S. Estrera and K. D. Luks, J. Chem. Eng. Data, 1987, 32, 201.
29. C. J. Peters, J. L. de Roo and J. de Swaan Arons, Fluid Phase Equilib., 1992, 72, 251.
30. D. H. Lam, A. Jangkamolkulchai and K. D. Luks, Fluid Phase Equilib., 1990, 60, 59.
31. E. Brunner, J. Chem. Thermodyn., 1990, 22, 335.