ABSTRACT
The utilization of excess quantities as the basis of a thermodynamic approach can simplify the prediction of multicomponent data from binary ones. Whereas in Part II the excess formalism was applied to the prediction of liquid phase adsorption on solids, in this paper, the liquid/air interface is investigated. In order to show the generality of the suggested approach, thermodynamic equations are developed in analogy to Part II. Surface tensions are predicted by different excess models and compared with experimental data. From predicted surface tensions, ternary adsorption isotherms on the liquid/air interface are calculated.
ABSTRACT
The adsorption isotherms of the binary n-alkane mixtures n-hexane/n-octane, n-octane/n-tetradecane, and n-hexane/n-tetradecane on the activated carbon TA 95 are measured at 298 K and described with mathematical functions. About 40 experimental values of the adsorption excess of the ternary mixture n-hexane/n-octane/n-tetradecane on activated carbon TA 95 at 298 K are gas chromatographically measured inside the ternary triangle. The ternary data are represented in the three-dimensional space with the help of transformation of coordinates and by utilization of the conception of the quasi-two-component representation of the mole fractions. A consistency test for the specific wetting Gibbs energies calculated from the binary data is carried out. The possibilities for a mathematical prediction of ternary data from adsorption data for the constituent binary mixtures are proved. Copyright 1999 Academic Press.