THERMODYNAMICS OF SOLUBILITIES IN MIXED SOLVENTS

Abstract

Several practical excess quantities of solid solubilities in mixed solvents have been defined by means of the solute-free volume fractions of the solvent components. Each excess quantity is expressed theoretically by a sum of two terms: the limiting term derived from the assumption of infinite dilution of solute and the correction term of solute concentration. They are given usually by a sum of size, physical, and association terms derived from the generalized FIory-Huggins equation. The theory has been applied to and compared with experimental iodine solubilities in two binary mixtures: benzene-cyclohexane and benzene-carbon tetrachloride.
The theoretical expressions derived in this paper are applicable to the correlation of gas solubility data measured at constant fugacity of the gas component.