Removal of atmospheric oxidants with annular denuders

Removal of Ethylene and Secondary Organic Aerosols Using UV-C254 + 185 nm with TiO2 Catalyst

“…Calibration curves were prepared for quantitative determinations. In the 254 + 185 nm UV irradiation experiments, a KI (potassium iodide)-coated annular denuder was used to selectively remove the ozone, since effluent gas with a high ozone content can seriously damage the GC column (Williams and Grosjean, 1990).…”

Estimating the uptake of traffic-derived NO 2 from 15 N abundance in Norway spruce needles

“…The principle of selective sampling of NO x compounds by a denuder system follows the rationale presented by Braman et al (1986), but is based on water-soluble and nitrogen-free coatings, which were partly used by Ferm and SjoÈ din (1985) and Williams and Grosjean (1987). The denuder system consisted of four tubular denuders (sand-blasted Pyrex tubes, 7 mm´10 mm´710 mm) in series for absorption of HNO 3 , HONO, NO 2 and NO, with coatings of NaF, Na 2 CO 3 /glycerine, and KOH/guaiacol (two tubes), respectively.…”

Ozone Catalytic Oxidation of Gaseous Toluene over MnO2-Based Ozone Decomposition Catalysts Immobilized on a Nonwoven Fabric

“…CO 2 and CO were determined simultaneously by GC-FID (GC-15A, Shimadzu, Kyoto, Japan) equipped with a methane converter (MT-221, GL Science, Tokyo, Japan). In the experiments with O 3 , a KI-coated annular denuder was used to remove the O 3 selectively, because effluent gas with a high level of O 3 can damage the GC column (Williams II and Grosjean, 1990). Low and high concentrations of O 3 were measured with a UV-absorption O 3 analyzer (UVAD-1000, Shimadzu, Kyoto, Japan) and by iodometric titration, respectively.…”