Application of conventional thermodynamic approximations to mixed-solvent gas—liquid chromatography

Conventional thermodynamic approximations indicate a general non-linear dependence of partition coefficient on stationary-phase composition in mixed-solvent gas—liquid chromatography (GLC). The deviations from linearity have been calulated for varying circumstances, and the fact that many reported experimental measurements appear to conform to an approximately linear relation is explained by an extrapolation of solubility-parameter theory. The same thermodynamic treatment has been used to predict the behaviour of partially miscible stationary phases in GLC.