title: Formation yields of C8 1,4-hydroxycarbonyls from OH + n-octane in the presence of NO.
abstract: 1,4-Hydroxycarbonyls are major products of the OH radical-initiated reactions of ≥ C₅ n-alkanes in the presence of NO. However, because of a lack of commercially available standards of 1,4-hydroxycarbonyls and difficulties in using gas chromatography for their analysis without prior derivatization, quantification of 1,4-hydroxycarbonyls in OH + alkane reactions has proven difficult. We have used an annular denuder coated with XAD resin and further coated with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine for in situ derivatization of the 1,4-hydroxycarbonyls formed from the OH + n-octane reaction in the presence of NO. Quantification was achieved by using 2,5-hexanedione as an internal standard. Formation yields for (7-hydroxy-4-octanone + 6-hydroxy-3-octanone + 5-hydroxy-2-octanone) and of 4-hydroxyoctanal of 61 ± 11% and 2.1 ± 0.5%, respectively, were obtained. When combined with previously measured or estimated formation yields for octyl nitrates and hydroxyoctyl nitrates, 93 ± 15% of the overall reaction products are accounted for, indicating that no additional reaction pathways remain to be identified.
authors.affiliation: Air Pollution Research Center, University of California, Riverside, California 92521, USA.
authors.forename: Sara M
authors.initials: SM
authors.lastname: Aschmann
authors.forename: Janet
authors.initials: J
authors.lastname: Arey
authors.forename: Roger
authors.initials: R
authors.lastname: Atkinson
mesh_terms: D000473:Alkanes / Q000737:chemistry*; D005410:Flame Ionization; D008401:Gas Chromatography-Mass Spectrometry; D017665:Hydroxyl Radical / Q000737:chemistry*; D008697:Methane / Q000737:chemistry; D009569:Nitric Oxide / Q000737:chemistry*; D009795:Octanes / Q000737:chemistry*
chemical_list: D000473:Alkanes; D009795:Octanes; D009569:Nitric Oxide; D017665:Hydroxyl Radical; D008697:Methane; C026728:octane