title: Secondary Organic Aerosol Formation via 2-Methyl-3-buten-2-ol Photooxidation: Evidence of Acid-Catalyzed Reactive Uptake of Epoxides.
abstract: Secondary organic aerosol (SOA) formation from 2-methyl-3-buten-2-ol (MBO) photooxidation has recently been observed in both field and laboratory studies. Similar to the level of isoprene, the level of MBO-derived SOA increases with elevated aerosol acidity in the absence of nitric oxide; therefore, an epoxide intermediate, (3,3-dimethyloxiran-2-yl)methanol (MBO epoxide), was synthesized and tentatively proposed to explain this enhancement. In this study, the potential of the synthetic MBO epoxide to form SOA via reactive uptake was systematically examined. SOA was observed only in the presence of acidic aerosol. Major SOA constituents, 2,3-dihydroxyisopentanol and MBO-derived organosulfate isomers, were chemically characterized in both laboratory-generated SOA and in ambient fine aerosol collected from the BEACHON-RoMBAS field campaign during the summer of 2011, where MBO emissions are substantial. Our results support the idea that epoxides are potential products of MBO photooxidation leading to the formation of atmospheric SOA and suggest that reactive uptake of epoxides may explain acid enhancement of SOA observed from other biogenic hydrocarbons.
authors.affiliation: Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599, United States.
authors.forename: Haofei
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599, United States.
authors.forename: Zhenfa
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599, United States.
authors.forename: Tianqu
authors.initials: T
authors.lastname: Cui
authors.affiliation: Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599, United States.
authors.forename: Ying-Hsuan
authors.initials: YH
authors.lastname: Lin
authors.affiliation: Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599, United States.
authors.forename: Neil A
authors.initials: NA
authors.lastname: Bhathela
authors.affiliation: Atmospheric Chemistry Division, National Center for Atmospheric Research , Boulder, Colorado 80307, United States.
authors.forename: John
authors.initials: J
authors.lastname: Ortega
authors.affiliation: Department of Environmental Science, Policy and Management, University of California , Berkeley, California 94720, United States ; Aerosol Dynamics Inc. , Berkeley, California 94710, United States.
authors.forename: David R
authors.initials: DR
authors.lastname: Worton
authors.affiliation: Department of Environmental Science, Policy and Management, University of California , Berkeley, California 94720, United States ; Department of Civil and Environmental Engineering, University of California , Berkeley, California 94720, United States.
authors.forename: Allen H
authors.initials: AH
authors.lastname: Goldstein
authors.affiliation: Atmospheric Chemistry Division, National Center for Atmospheric Research , Boulder, Colorado 80307, United States.
authors.forename: Alex
authors.initials: A
authors.lastname: Guenther
authors.affiliation: Cooperative Institute for Research in Environmental Sciences and Department of Chemistry and Biochemistry, University of Colorado , Boulder, Colorado 80309, United States.
authors.forename: Jose L
authors.initials: JL
authors.lastname: Jimenez
authors.affiliation: Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599, United States.
authors.forename: Avram
authors.initials: A
authors.lastname: Gold
authors.affiliation: Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599, United States.
authors.forename: Jason D
authors.initials: JD
authors.lastname: Surratt