Performances of Various Adsorbents for the Trapping and Analysis of Organohalogenated Air Pollutants by Gas Chromatography

Abstract

A comparison of the performances of various adsorbents (porous polymers Porapak Q, Porapak T, Tenax GC) and graphitized carbon black (Carbopack C-HT) is presented in terms of retention properties towards the most usual chlorofluoroalkanes. A practical example of separation and identification of the most common halocarbons by gas chromatography on Carbopack C-HT is given. Using an electron capture detector permits selective sensitive detection, and temperature programming from -60 to + 60°C allows the resolution of methyl chloride from oxygen and water. A preconcentration of the sample is necessary for compounds, like CH₃Cl, for which detector response is low. This can be done on Porapak Q traps cooled to -50°C.