Article

Evidence for Organosulfates in Secondary Organic Aerosol

University of Antwerp, Antwerpen, Flemish, Belgium
Environmental Science and Technology (Impact Factor: 5.33). 02/2007; 41(2):517-27. DOI: 10.1021/es062081q
Source: PubMed

ABSTRACT

Recent work has shown that particle-phase reactions contribute to the formation of secondary organic aerosol (SOA), with enhancements of SOA yields in the presence of acidic seed aerosol. In this study, the chemical composition of SOA from the photooxidations of alpha-pinene and isoprene, in the presence or absence of sulfate seed aerosol, is investigated through a series of controlled chamber experiments in two separate laboratories. By using electrospray ionization-mass spectrometry, sulfate esters in SOA produced in laboratory photooxidation experiments are identified for the first time. Sulfate esters are found to account for a larger fraction of the SOA mass when the acidity of seed aerosol is increased, a result consistent with aerosol acidity increasing SOA formation. Many of the isoprene and alpha-pinene sulfate esters identified in these chamber experiments are also found in ambient aerosol collected at several locations in the southeastern U.S. It is likely that this pathway is important for other biogenic terpenes, and may be important in the formation of humic-like substances (HULIS) in ambient aerosol.

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    • "Analysis of filter extracts is commonly performed by liquid chromatography (LC) and gas chromatography (GC), coupled to mass spectrometry with the use of electron ionization (EI), chemical ionization (CI), electrospray ionization (ESI), and atmospheric pressure chemical ionization (APCI) (Dye and Yttri, 2005; Simpson et al., 2005; Surratt et al., 2006 and 2007a, b; Lavrich and Hays, 2007; Szmigielski et al., 2007; Lin et al., 2012). Major organic classes in SOA that have been identified from filter-based analysis include (nitrooxy)organosulfates (Surratt et al., 2007a, b and 2008; Iinuma et al., 2007; Chan et al., 2011), dimers, trimers, and oligomers (Jang et al., 2002; Limbeck et al., 2003; Gao et al., 2004; Kalberer et al., 2004; Fahnestock et al., 2014), and humic-like substances (Gelencser et al., 2002; Graham et al., 2002). A limitation of filterbased analysis is low time resolution and, consequently, the inability to track particle-phase kinetics. "
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