title: Identification of organic acids in secondary organic aerosol and the corresponding gas phase from chamber experiments.
abstract: Organic acids in the gas and aerosol phase from photooxidation of 1,3,5-trimethylbenzene in the presence of 300 ppb propene and 300 ppb NOx in smog chamber experiments were determined using a wet effluent diffusion denuder/aerosol collector coupled to ion chromatography (IC) with conductivity detection. Behind the IC, the samples were collected using a fraction collector, for identification of unresolved/unidentified organic acids with IC-mass spectrometry (MS). In total, 20 organic acids were found with MS of which 10 were identified. The organic acids identified offline by IC-MS were then further quantified based on the online IC data. The identification was additionally confirmed with gas chromatography-mass spectrometry. At the maximum aerosol concentration, organic acids comprised 20-45% of the total aerosol mass. The method has a detection limit of 10-100 ng/m3 for the identified carboxylic acids.
authors.affiliation: Laboratory of Atmospheric Chemistry, Paul Scherrer Institut (PSI), 5232 Villigen PSI, Switzerland.
authors.forename: R
authors.initials: R
authors.lastname: Fisseha
authors.forename: J
authors.initials: J
authors.lastname: Dommen
authors.forename: M
authors.initials: M
authors.lastname: Sax
authors.forename: D
authors.initials: D
authors.lastname: Paulsen
authors.forename: M
authors.initials: M
authors.lastname: Kalberer
authors.forename: R
authors.initials: R
authors.lastname: Maurer
authors.forename: F
authors.initials: F
authors.lastname: Höfler
authors.forename: E
authors.initials: E
authors.lastname: Weingartner
authors.forename: U
authors.initials: U
authors.lastname: Baltensperger