title: Measurement of secondary products during oxidation reactions of terpenes and ozone based on the PTR-MS analysis: effects of coexistent carbonyl compounds.
abstract: Continuous measurements using proton transfer reaction mass spectrometry (PTR-MS) can be used to describe the production processes of secondary products during ozone induced oxidation of terpenes. Terpenes are emitted from woody building materials, and ozone is generated from ozone air purifiers and copy machines in indoor environments. Carbonyl compounds (CCs) are emitted by human activities such as smoking and drinking alcohol. Moreover, CCs are generated during ozone oxidation of terpenes. Therefore, coexistent CCs should affect the ozone oxidation. This study has focused on the measurement of secondary products during the ozone oxidation of terpenes based on the use of PTR-MS analysis and effects of coexistent CCs on oxidized products. Experiments were performed in a fluoroplastic bag containing α-pinene or limonene as terpenes, ozone and acetaldehyde or formaldehyde as coexistent CCs adjusted to predetermined concentrations. Continuous measurements by PTR-MS were conducted after mixing of terpenes, ozone and CCs, and time changes of volatile organic compounds (VOCs) concentrations were monitored. Results showed that, high-molecular weight intermediates disappeared gradually with elapsed time, though the production of high-molecular weight intermediates was observed at the beginning. This phenomenon suggested that the ozone oxidation of terpenes generated ultrafine particles. Coexistent CCs affected the ozone oxidation of α-pinene more than limonene.
authors.affiliation: Department of Environment Systems, Institute of Environmental Studies, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa-no-ha 5-1-5, Kashiwa-shi, Chiba 277-8563, Japan. yusuke_ishizuka@yy.k.u-tokyo.ac.jp
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Ishizuka
authors.forename: Masahiro
authors.initials: M
authors.lastname: Tokumura
authors.forename: Atsushi
authors.initials: A
authors.lastname: Mizukoshi
authors.forename: Miyuki
authors.initials: M
authors.lastname: Noguchi
authors.forename: Yukio
authors.initials: Y
authors.lastname: Yanagisawa
mesh_terms: D007659:Ketones / Q000737:chemistry*; D007700:Kinetics; D013058:Mass Spectrometry / Q000379:methods*; D010084:Oxidation-Reduction; D010126:Ozone / Q000737:chemistry*; D013729:Terpenes / Q000737:chemistry*; D055549:Volatile Organic Compounds / Q000737:chemistry
chemical_list: D007659:Ketones; D013729:Terpenes; D055549:Volatile Organic Compounds; D010126:Ozone