Gas‐solid chromatography of hydrocarbons on activated alumina

Abstract

Abstract Volatile hydrocarbons representative of those in autoxidizing fats were analyzed on a single column of activated alumina by gas‐solid adsorption chromatography (GSC). Mixtures of C 1 to C 8 paraffins and a ‐olefins were readily separated from one another, and from several branched hydrocarbons in less than 40 min. Semilog plots of carbon number versus log retention time for these individual mixtures indicate that good separations may be expected when all components are present simultaneously. Alumina is a unique chromatographic substrate for these separations. Since no liquid phase is employed, wide temperature ranges may be applied, column bleeding is eliminated and the system becomes ideal for temperature programming even on single column instruments. This system of GSC offers a convenient and direct method for hydrocarbon analysis since more polar materials such as aldehydes, ketones and esters are irreversibly adsorbed on alumina. It shows promise not only for the analysis of volatiles in the flavor evaluation of edible oils, but also as an aid in solving many other food and biological problems.