Grantee Research Project Results
2009 Progress Report: SOA Volatility Evolution: Formation and Oxidation over the Lifecycle of PM2.5
EPA Grant Number: R833746Title: SOA Volatility Evolution: Formation and Oxidation over the Lifecycle of PM2.5
Investigators: Donahue, Neil , Kroll, Jesse H. , Pandis, Spyros N. , Worsnop, Douglas R.
Institution: Carnegie Mellon University , Aerodyne Research Inc.
EPA Project Officer: Chung, Serena
Project Period: September 1, 2007 through August 31, 2011
Project Period Covered by this Report: September 1, 2007 through November 30,2010
Project Amount: $599,990
RFA: Sources and Atmospheric Formation of Organic Particulate Matter (2007) RFA Text | Recipients Lists
Research Category: Air Quality and Air Toxics , Particulate Matter , Air
Objective:
The objective of this project is to identify the major mechanisms for the aging of organic particulate matter in the atmosphere and to implement accurate parameterizations of those findings in air quality models. In so doing, we strive to understand the relative contribution of human activity and natural emissions to organic aerosol levels and so to enable and inform policy actions aimed at organic-aerosol reductions.
Progress Summary:
We have made significant progress on both the experimental and laboratory aspects of this project. Two doctoral students, Kaytlin Henry (Chemical Engineering, experimental) and Benjamin Murphy (Chemical Engineering, modeling), are directly supported by the grant, while a third, Lea Hildebrandt (Chemical Engineering, and Engineering Public Policy, experimental and policy), is a National Science Foundation (NSF) fellow whose research falls under this project as well. Five undergraduate researchers, Christina Maksymiuk (Chemistry B.S., 2008), Jyoti Bhapat (Chemistry B.S., 2009), Amy Maples (Chemical Engineering B.S., expected 2010), Peter Mellott (Chemical Engineering B.S., expected 2010), and Melanie Bothe (Chemical Engineering Technische Universität Dortmund, visiting student in 2009), have participated in project research. In the case of Christina Maksymiuk, her research led to a first-author paper in a special issue of Physical Chemistry, Chemical Physics devoted to organic aerosol chemistry. Melanie Bothe conducted research for her principal research paper. Engaging women and under-represented minorities in the physical sciences is an educational objective of our program: two of the three doctoral students and four of the five undergraduate researchers are women.
A notable experimental undertaking for 2008 was an intensive series of experiments in July involving the High-Resolution Aerosol Mass Spectrometer, operated by co-investigator Jesse Kroll at Carnegie Mellon University (CMU), for three weeks. We examined the interaction of anthropogenic and biogenic secondary organic aerosol (SOA) by using an isotopic label on toluene (a major source of anthropogenic SOA) to separate it from alpha-pinene (α-pinene) SOA, generating first one then the other SOA by oxidation of each precursor, and then observing the mixing behavior with high-resolution mass spectrometry.
During the remainder of the year, we separately investigated SOA formation from toluene and α-pinene. We found significantly higher SOA yields than previous observations (confirming a recent finding from the California Institute of Technology for low-NOx conditions and extending it to high-NOx conditions). This research was published in Atmospheric Chemistry and Physics. For α-pinene, we examined the volatility of SOA using thermodenuder measurements and also the influence of aging by exposure to OH radicals. Again this showed significant changes in SOA concentrations, with an effect that appears to depend dramatically on the presence of UV light.
The aging of α-pinene SOA became the centerpiece of a multiple-chamber experiment conducted by the Principal Investigator as part of his sabbatical research during 2008-2009. This research included the STAR-supported chamber experiments at Carnegie Mellon University and parallel experiments at the Paul Scherrer Institute in Switzerland, and Forschungszentrums in Karlsruhe and Juelich, Germany. Using different chambers with different radical sources, different wall characteristics, and different volume-to-area ratios, we were able to probe the dramatic consequences. The bottom line is that SOA from this important biogenic source can easily double or even triple after aging by OH radicals equivalent to roughly one day of exposure, but the aging shows signs of being quite sensitive to photochemistry. Preliminary implementations of aging mechanisms in our 2-dimensional volatility basis set (2D-VBS, see below) are consistent with the chamber experiments but show much less aged SOA formation.
We have implemented the volatility basis set developed under our previous STAR grant in the air quality model PMCAMx and investigated the effect of these aging reactions on SOA levels. The upshot is that increased SOA formation from toluene oxidation substantially improves model-measurement agreement, while enhanced SOA from α-pinene SOA aging is inconsistent with organic aerosol measurements in the southeastern United States. The model disagreement with α‑pinene aging in the 1-dimensional VBS (1D-VBS) used in this model may well be alleviated with the 2D-VBS aging mechanism that now is constrained by chamber observations from this STAR project.
Two papers in Geophysical Research Letters provide substantial constraints on the thermodynamics associated with organic-aerosol phase partitioning. One, by Noenne Prisle (visiting doctoral student from Copenhagen), shows that we can observe a mild enhancement in SOA formed on dry inorganic seed particles as humidity increases only after those seeds deliquesce, but that the SOA and the inorganic phases remain largely separate. A second complementary study supported under STAR Grant No. R833748 showed that mixing among different organic aerosol types (SOA and POA) is quite sensitive to the composition of the organics, but that complex mixtures such as actual diesel emissions appear to mix with SOA, while less complex mixtures (such as pure oil) do not. This has significant implications to OA mixing assumptions used in chemical transport models.
Future Activities:
We are planning a final research visit by Jesse Kroll to Carnegie Mellon University this summer to combine measurements of oxidizing organic vapors with his new mass spectrometer and high-resolution Aerosol Mass Spectrometer measurements with our own HR-AMS, obtained with NSF major research instrumentation funding matched by a grant from the Wallace Research Foundation.
We will continue individual SOA formation experiments on carefully selected sequences of precursors designed to mimic first generation SOA compounds (for example, pinonaldehyde from α-pinene oxidation). These measurements will begin to fill in important aging matrix elements associated with the 2D-VBS.
Journal Articles on this Report : 9 Displayed | Download in RIS Format
Other project views: | All 68 publications | 31 publications in selected types | All 31 journal articles |
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Type | Citation | ||
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Bothe M, Donahue NM. Organic aerosol formation in citronella candle plumes. Air Quality, Atmosphere and Health 2010;3(3):131-137. |
R833746 (2009) R833746 (2010) R833746 (Final) |
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Chacon-Madrid HJ, Presto AA, Donahue NM. Functionalization vs. fragmentation: n-aldehyde oxidation mechanisms and secondary organic aerosol formation. Physical Chemistry Chemical Physics 2010;12(42):13975-13982. |
R833746 (2009) R833746 (2010) R833746 (Final) |
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Donahue NM, Robinson AL, Pandis SN. Atmospheric organic particulate matter: from smoke to secondary organic aerosol. Atmospheric Environment 2009;43(1):94-106. |
R833746 (2008) R833746 (2009) R833746 (2010) R833746 (Final) R833748 (2008) R833748 (2010) R833748 (Final) |
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Hallquist M, Wenger JC, Baltensperger U, Rudich Y, Simpson D, Claeys M, Dommen J, Donahue NM, George C, Goldstein AH, Hamilton JF, Herrmann H, Hoffmann T, Iinuma Y, Jang M, Jenkin ME, Jimenez JL, Kiendler-Scharr A, Maenhaut W, McFiggans G, Mentel TF, Monod A, Prevot ASH, Seinfeld JH, Surratt JD, Szmigielski R, Wildt J. The formation, properties and impact of secondary organic aerosol:current and emerging issues. Atmospheric Chemistry and Physics 2009;9(14):5155-5236. |
R833746 (2008) R833746 (2009) R833746 (2010) R833746 (Final) R833749 (2009) R833749 (Final) |
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Hildebrandt L, Donahue NM, Pandis SN. High formation of secondary organic aerosol from the photo-oxidation of toluene. Atmospheric Chemistry and Physics 2009;9(9):2973-2986. |
R833746 (2009) R833746 (2010) R833746 (Final) |
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Jimenez JL, Canagaratna MR, Donahue NM, Prevot AS, Zhang Q, Kroll JH, DeCarlo PF, Allan JD, Coe H, Ng NL, Aiken AC, Docherty KS, Ulbrich IM, Grieshop AP, Robinson AL, Duplissy J, Smith JD, Wilson KR, Lanz VA, Hueglin C, Sun YL, Tian J, Laaksonen A, Raatikainen T, Rautiainen J, Vaattovaara P, Ehn M, Kulmala M, Tomlinson JM, Collins DR, Cubison MJ, Dunlea EJ, Huffman JA, Onasch TB, Alfarra MR, Williams PI, Bower K, Kondo Y, Schneider J, Drewnick F, Borrmann S, Weimer S, Demerjian K, Salcedo D, Cottrell L, Griffin R, Takami A, Miyoshi T, Hatakeyama S, Shimono A, Sun JY, Zhang YM, Dzepina K, Kimmel JR, Sueper D, Jayne JT, Herndon SC, Trimborn AM, Williams LR, Wood EC, Middlebrook AM, Kolb CE, Baltensperger U, Worsnop DR. Evolution of organic aerosols in the atmosphere. Science 2009;326(5959):1525-1529. |
R833746 (2009) R833746 (2010) R833746 (Final) R831080 (Final) R832161 (Final) R833747 (Final) R833748 (2010) R833748 (Final) |
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Maksymiuk CS, Gayahtri C, Gil RR, Donahue NM. Secondary organic aerosol formation from multiphase oxidation of limonene by ozone: mechanistic constraints via two-dimensional heteronuclear NMR spectroscopy. Physical Chemistry Chemical Physics 2009;11(36):7810-7818. |
R833746 (2009) R833746 (2010) R833746 (Final) |
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Murphy BN, Pandis SN. Simulating the formation of semivolatile primary and secondary organic aerosol in a regional chemical transport model. Environmental Science & Technology 2009;43(13):4722-4728. |
R833746 (2008) R833746 (2009) R833746 (2010) R833746 (Final) R833374 (Final) |
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Prisle NL, Engelhart GJ, Bilde M, Donahue NM. Humidity influence on gas-particle phase partitioning of α-pinene + O3 secondary organic aerosol. Geophysical Research Letters 2010;37(1):L01802 (5 pp.). |
R833746 (2009) R833746 (2010) R833746 (Final) |
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Supplemental Keywords:
Air Quality Modeling, Smog, Particulate Matter, Organics.Relevant Websites:
CAPS - Center for Atmospheric Particle Studies | Carnegie Mellon University ExitProgress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.