Solute Retention in Column Liquid Chromatography. X. Determination of Solute Infinite-Dilution Activity Coefficients in Methanol, Water, and Their Mixtures, by Combined Gas-Liquid and Liquid-Liquid Chromatography

Abstract

The Raoult's-law activity coefficients of 3- to 7-carbon aliphatic aldehyde, ketone, ester, and alcohol solutes at infinite dilution in methanol, water, and mixtures of the two and in polydimethylsiloxane, all at 293–308 K, have been determined for the first time by appropriate combination of GLC and LLC retention data. The latter data are reported in terms of mole fractions, while the former are given in concentration units of molality. However, interpretation of the data is difficult because of the multiplicity of the retention mechanisms. Nevertheless, the combined GLC/LLC technique, which had been applied previously only to pure solvents, is said to offer a number of advantages over static techniques for the determination of solute infinite-dilution activity coefficients with volatile solvents, especially with mixtures of solvents.