Journal
FLUID PHASE EQUILIBRIA
Volume 266, Issue 1-2, Pages 105-128Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/j.fluid.2008.02.004
Keywords
combining rules; unlike intermolecular-potential parameters; mixture fluid phase equilibria
Ask authors/readers for more resources
We show how to extend the Hudson-McCoubrey combining rules, which were derived assuming the Lennard-Jones potential, for use with intermolecular potentials that are not of Lennard-Jones form. In particular, we illustrate the method by deriving combining rules for use with the square-well intermolecular potential. We show how these combining rules may be applied for equations of state such as the statistical associating fluid theory (SAFT), and that they perform at least as well as, and usually far better than, the standard Lorentz-Berthelot rules for all mixtures of simple molecules that we have considered. Liquid-liquid-equilibrium as well as vapour-liquid-equilibrium data are demonstrated to be important in judging the quality of combining rules. A methodology for the inclusion of the effect of polar interactions in our combining rules is suggested, however the success for these systems is mixed. The theory provides an excellent description of the thermodynamic properties of water vapour + methane and rationalises recent, apparently contradictory, models of the mixture of carbon dioxide + water, however the approach is less successful for mixtures such as carbon monoxide + hydrogen sulphide. This indicates that further work is still required for reliable prediction of binary-interaction parameters in mixtures of polar molecules. (C) 2008 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available