title: [Analysis of atmospheric pollutants with coupled gas chromatography-atomic absorption or thermodesorption-gas chromatography].
abstract: We have perfected a specific and original analytical method suitable for organic and inorganic compounds using sampled run-off water collected nearby a filling station. The dissolved lead species are volatilized by substituting the inorganic ligands with hydrogen, using sodium-borohydride in a suitable reaction medium (H2O2, KOH). The volatile lead hydrides are then trapped on a gas chromatographic column filled with Chromosorb W impregnated with 2% of OV 275 and immersed in liquid nitrogen. After desorption, the products are analysed by atomic absorption spectroscopy. We have carried out the analysis of aldehydes mixtures, sampled from a smog chamber. They are trapped, at room temperature, in a glass column filled with Tenax. These pollutants are then heated at 250 degrees C under a flow of nitrogen, and trapped again in a melted silica capillary column at -110 degrees C. This trapping being over, the column is drastically heated at 200 degrees C, which drives the products into the capillary column of a gas-chromatograph apparatus. This method has also enabled us to carry out a direct analysis of these pollutants sorbed on particles which have been placed into the glass column. this thermodesorption-gas chromatography system, coupled with a mass-spectrometry apparatus, allows us to identify and analyse most atmospheric pollutants.
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000395:Air Pollutants, Occupational / Q000032:analysis; D000447:Aldehydes / Q000032:analysis; D002849:Chromatography, Gas; D008670:Metals / Q000032:analysis; D013054:Spectrophotometry, Atomic
chemical_list: D000393:Air Pollutants; D000395:Air Pollutants, Occupational; D000447:Aldehydes; D008670:Metals
vernacular_title: Analyse de polluants atmospheriques par couplage chromatographie en phase gazeuse-absorption atomique ou thermodesorption-chromatographie en phase gazeuse.