Determination of hydrocarbon-water partition coefficients from chromatographic data and based on solution thermodynamics and theory

Abstract

The octanol—water and hexadecane-water partition coefficients for series of alkylbenzenes, alkanes, alkenes, alcohols, and bromoalkanes were determined by the generator column technique and compared favorably to those calculated from the activity coefficients in each phase. A lattice-model theory suggested and the data confirmed that the logarithms of the partition coefficients are linearly related to each other and to the solute molar volume for each homologous series. As predicted by the theory, the slopes of the linear relationships between the logarithms of the partition coefficients and solute molar volume were the same for all homologous series studied. Furthermore, the logarithms of the octanol-water partition coefficients were linearly related ( r 2 = 0.993) to the logarithms of the reversed-phase liquid chromatographic adjusted retention volumes determined by extrapolation to 100% water as the mobile phase for a variety of the solutes.