title: Combination of sorption tube sampling and thermal desorption with hollow waveguide FT-IR spectroscopy for atmospheric trace gas analysis: determination of atmospheric ethene at the lower ppb level.
abstract: The determination of organic trace gases in the ambient environment at the lower ppb level is demonstrated based on a novel technique combining sorption tube sampling on Molsieve and Carbosieve S-III, thermal desorption, and detection of the trace analyte by hollow waveguide Fourier transform infrared (HWG-FT-IR) spectroscopy. While ethene concentrations of approximately 5 ppm can be directly observed using HWG-FT-IR, enrichment factors of up to 5000 were achieved by sorption tube sampling and thermal desorption. Detection limits of approximately 1 ppb are reported. Efficient enrichment by the sampling tube is achieved due to the favorable internal volume ( approximately 0.4 cm(3) at a length of 470 mm) of the hollow waveguide serving as a miniaturized gas cell. This new method was validated for ethene by thermodesorption-cryofocusing-GC-FID as the reference method. Analytical performance has been compared for standard gas mixtures and for ethene measurements in urban air. Finally, ethene data from a sampling campaign at two alpine sites in Tyrol/Austria are presented.
authors.affiliation: Institute of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/164, A-1060 Vienna, Austria.
authors.forename: Olga A
authors.initials: OA
authors.lastname: Pogodina
authors.forename: Victor V
authors.initials: VV
authors.lastname: Pustogov
authors.forename: Fabiano
authors.initials: F
authors.lastname: de Melas
authors.forename: Christina
authors.initials: C
authors.lastname: Haberhauer-Troyer
authors.forename: Erwin
authors.initials: E
authors.lastname: Rosenberg
authors.forename: Hans
authors.initials: H
authors.lastname: Puxbaum
authors.forename: Alexandra
authors.initials: A
authors.lastname: Inberg
authors.forename: Nathan
authors.initials: N
authors.lastname: Croitoru
authors.forename: Boris
authors.initials: B
authors.lastname: Mizaikoff