Use of a Displacement Model for Solvent Sorption to Study Non-SpecificSelectivity in Reversed-Phase Liquid Chromatography

摘要

A thermodynamic equation is derived for the non-specific selectivity of alkylbonded phases as a function of the mobile phase composition using a displacement mechanism to model the sorption of solvents into the bonded phase. The equation is used to calculate the thermodynamic parameters which characterize the incremental behavior of a hydrophobic group in ethyl alkanoate and methyl perfluoroalkanoate ester solutes chromatographed with water-methanol and water-acetonitrile mobile phases on both octyl and octadecyl bonded phases.