Relative responses of thermal conductivity detector to halocarbons

For the purpose of gas-chromatographic determination of the products obtained from radiolysis or photolysis of halocarbons, the relative TCD responses to 33 kinds of C1C4 halocarbons containing fluorine, chlorine, and bromine atoms were measured by using a Silicone DC 550 column. The relative responses per mole to perfluoroalkanes (CnF2n+2) increase with the increase in molecular weight, whereas those for chlorofluorocarbons and bromochlorofluorocarbons tend to deviate systematically from the correlation according to stepwise substitutions of chlorine for fluorine and bromine for chlorine. The relative responses per weight to these halocarbons generally decrease with the increase in molecular weight; they are also influenced systematically by the halogen substitution in the molecules. The detector sensitivities to the halocarbons other than those listed here may be estimated by means of the extrapolation based on such correlations with the molecular weight and the halogen composition.