Partition coefficients by curve fitting: the use of two different octanol volumes in a dual-phase potentiometric titration.

ABSTRACT

It is shown that when two different volumes of the second phase are employed in a single dual-phase potentiometric titration, the partition coefficients of the most highly ionized species can be readily calculated by refinement of the parameters for the dual-purpose titration equations. Graphical comparison of the calculated titration curve with that obtained experimentally is helpful in making initial estimates of the parameters.