Abstract
The coordination number was first reported by Ouchiyama and Tanaka for particulate materials having a range of sizes. Based on this statistical theory the present paper deals with the problem of predicting whether a given binary liquid mixture might form an azeotrope or not.
First, the total sum of intermolecular potentials should be calculated from the numbers of A and B molecules adjacent to a molecule of A component and B component.
Assuming the ratio of the total sum to the boiling temperature of the mixture to be constant, a maximum value of the total potentials can be obtained in relationship to the mole fraction, by varying the degree of interaction between A molecule and B molecule until the mole fraction to give the maximum coincides with the mole fration of the exist ing azeotropic points of some 40 kinds. The degree of interaction thus obtained between the different kind of molecules can be correlated with the molecular parameters with respect to size, shape and potential.
As the results, the azeotrope prediction can be made to 88% probability with 137 mixtures available, by using only the molecular parameters of each component. If a specific binary mixture is predicted to be an azeotropic one, then the azeotropic point (temperature and concentration) can also be evaluated quite satisfactorily. The boiling curves for some selected binary systems are illustrated from the present theory. Agreement between the theory and experimental data is reasonably good.
