DETERMINATION OF VOLATILE HYDROCARBONS IN THE ATMOSPHERIC AIR

Relatively simple analytical methods for the determination of light hydrocarbons in the atmospheric air were developed. The methods employ enrichment procedures and gas chromatography techniques. AliphatiC C2-C4 hydrocarbons are preconcentrated by the freezeout in a trap cooled with liquid nitrogen and then analyzed on a 10% TCEP column. The limit of detection is 0.05 mug of ethane and 0.3 mug of n-pentane per one cubic meter of air. Aliphatic C4-C6 hydrocarbons are preconcentrated by the sorption in activated carbon, desorbed with CS2 and analyzed using a 13% Triton X-100 column. The limit of detection is 4 mug of n-pentane and 8 mug of n-hexane per one cubic meter of air. Light aromatic hydrocarbons undergo sorption in the activated carbon, followed by desorption with CS2 and analysis on either 10% TCEP or 10% Carbowax columns. The limit of detection is 10 mug of benzene and 4 mug of o-xylene in a cubic meter of air.