Thermodynamics of extraction equilibria. Part 6. A further study of the method for determination of equilibrium constants of extraction processes
Abstract
The equilibrium constant (K) expression of the extraction of an inorganic compound (M) from the aqueous phase by an organic solvent (S) forming a solvate (M·nS), rearranged in the form –log aM=y= log K+ log asn/aMS(a= chemical activity of species), has been used to determine K. The method is based on the appearance of an inflexion point in a plot of the experimental data as y= f(cMS), where c denotes analytical concentration. The quotient aSn/aMS at the inflexion point can be substituted by an expression containing the total concentrations of the solvent and the compound extracted.