A study of the ability of pure secondary organic aerosol to act as cloud condensation nuclei

Abstract. Secondary organic aerosol (SOA) and oxidized primary organic aerosol (OPOA) were produced in laboratory experiments from the oxidation of fourteen precursors representing atmospherically relevant biogenic and anthropogenic sources. The SOA and OPOA particles were generated via controlled exposure of precursors to OH radicals and/or O3 in a Potential Aerosol Mass (PAM) flow reactor over timescales equivalent to 1–20 days of atmospheric aging. Aerosol mass spectra of SOA and OPOA were measured with an Aerodyne aerosol mass spectrometer (AMS). The fraction of AMS signal at m/z = 43 and m/z = 44 (f43, f44), the hydrogen-to-carbon (H/C) ratio, and the oxygen-to-carbon (O/C) ratio of the SOA and OPOA were obtained, which are commonly used to characterize the level of oxidation of oxygenated organic aerosol (OOA). The results show that PAM-generated SOA and OPOA can reproduce and extend the observed f44–f43 composition beyond that of ambient OOA as measured by an AMS. Van Krevelen diagrams showing H/C ratio as a function of O/C ratio suggest an oxidation mechanism involving formation of carboxylic acids concurrent with fragmentation of carbon-carbon bonds. Cloud condensation nuclei (CCN) activity of PAM-generated SOA and OPOA was measured as a function of OH exposure and characterized as a function of O/C ratio. CCN activity of the SOA and OPOA, which was characterized in the form of the hygroscopicity parameter κorg, ranged from 8.4×10−4 to 0.28 over measured O/C ratios ranging from 0.05 to 1.42. This range of κorg and O/C ratio is significantly wider than has been previously obtained. To first order, the κorg-to-O/C relationship is well represented by a linear function of the form κorg = (0.18±0.04) ×O/C + 0.03, suggesting that a simple, semi-empirical parameterization of OOA hygroscopicity and oxidation level can be defined for use in chemistry and climate models.

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Cloud condensation nuclei (CCN) activity of aliphatic amine secondary aerosol

Atmospheric Chemistry and Physics ◽

10.5194/acp-14-5959-2014 ◽

2014 ◽

Vol 14 (12) ◽

pp. 5959-5967 ◽

Cited By ~ 6

Author(s):

X. Tang ◽

D. Price ◽

E. Praske ◽

D. N. Vu ◽

K. Purvis-Roberts ◽

...

Keyword(s):

Hydroxyl Radical ◽

Aliphatic Amine ◽

Secondary Organic Aerosol ◽

Cloud Condensation Nuclei ◽

Organic Aerosol ◽

Nitrate Radical ◽

Condensation Nuclei ◽

Primary Aliphatic Amine ◽

Secondary Aerosol ◽

Ccn Activity

Abstract. Aliphatic amines can form secondary aerosol via oxidation with atmospheric radicals (e.g., hydroxyl radical and nitrate radical). The particle can contain both secondary organic aerosol (SOA) and inorganic salts. The ratio of organic to inorganic materials in the particulate phase influences aerosol hygroscopicity and cloud condensation nuclei (CCN) activity. SOA formed from trimethylamine (TMA) and butylamine (BA) reactions with hydroxyl radical (OH) is composed of organic material of low hygroscopicity (single hygroscopicity parameter, κ, ≤ 0.25). Secondary aerosol formed from the tertiary aliphatic amine (TMA) with N2O5 (source of nitrate radical, NO3) contains less volatile compounds than the primary aliphatic amine (BA) aerosol. As relative humidity (RH) increases, inorganic amine salts are formed as a result of acid–base reactions. The CCN activity of the humid TMA–N2O5 aerosol obeys Zdanovskii, Stokes, and Robinson (ZSR) ideal mixing rules. The humid BA + N2O5 aerosol products were found to be very sensitive to the temperature at which the measurements were made within the streamwise continuous-flow thermal gradient CCN counter; κ ranges from 0.4 to 0.7 dependent on the instrument supersaturation (ss) settings. The variance of the measured aerosol κ values indicates that simple ZSR rules cannot be applied to the CCN results from the primary aliphatic amine system. Overall, aliphatic amine aerosol systems' κ ranges within 0.2 < κ < 0.7. This work indicates that aerosols formed via nighttime reactions with amines are likely to produce hygroscopic and volatile aerosol, whereas photochemical reactions with OH produce secondary organic aerosol of lower CCN activity. The contributions of semivolatile secondary organic and inorganic material from aliphatic amines must be considered for accurate hygroscopicity and CCN predictions from aliphatic amine systems.

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Cloud condensation nuclei activation of monoterpene and sesquiterpene secondary organic aerosol

Journal of Geophysical Research Atmospheres ◽

10.1029/2004jd005754 ◽

2005 ◽

Vol 110 (D14) ◽

pp. n/a-n/a ◽

Cited By ~ 91

Author(s):

Kara E. Huff Hartz ◽

Thomas Rosenørn ◽

Shaun R. Ferchak ◽

Timothy M. Raymond ◽

Merete Bilde ◽

...

Keyword(s):

Secondary Organic Aerosol ◽

Cloud Condensation Nuclei ◽

Organic Aerosol ◽

Condensation Nuclei

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Oxidation of ambient biogenic secondary organic aerosol by hydroxyl radicals: Effects on cloud condensation nuclei activity

Geophysical Research Letters ◽

10.1029/2011gl049351 ◽

2011 ◽

Vol 38 (22) ◽

pp. n/a-n/a ◽

Cited By ~ 37

Author(s):

J. P. S. Wong ◽

A. K. Y. Lee ◽

J. G. Slowik ◽

D. J. Cziczo ◽

W. R. Leaitch ◽

...

Keyword(s):

Hydroxyl Radicals ◽

Secondary Organic Aerosol ◽

Cloud Condensation Nuclei ◽

Organic Aerosol ◽

Condensation Nuclei

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Cloud condensation nuclei activation of single-component and secondary organic aerosol

Journal of Aerosol Science ◽

10.1016/j.jaerosci.2004.06.006 ◽

2004 ◽

Vol 35 ◽

pp. 5-16

Author(s):

Kara E. Huff Hartz ◽

Thomas Rosenørn ◽

Timothy M. Raymond ◽

Shaun R. Ferchak ◽

Merete Bilde ◽

...

Keyword(s):

Secondary Organic Aerosol ◽

Cloud Condensation Nuclei ◽

Organic Aerosol ◽

Single Component ◽

Condensation Nuclei

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Laboratory studies of the chemical composition and cloud condensation nuclei (CCN) activity of secondary organic aerosol (SOA) and oxidized primary organic aerosol (OPOA)

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-11-13617-2011 ◽

2011 ◽

Vol 11 (5) ◽

pp. 13617-13653 ◽

Cited By ~ 4

Author(s):

A. T. Lambe ◽

T. B. Onasch ◽

P. Massoli ◽

D. R. Croasdale ◽

J. P. Wright ◽

...

Keyword(s):

Flow Reactor ◽

Secondary Organic Aerosol ◽

Cloud Condensation Nuclei ◽

Oxidation Mechanism ◽

Organic Aerosol ◽

Anthropogenic Sources ◽

Oh Radicals ◽

Condensation Nuclei ◽

Aerosol Mass ◽

Ccn Activity

Abstract. Secondary organic aerosol (SOA) and oxidized primary organic aerosol (OPOA) were produced in laboratory experiments from the oxidation of fourteen precursors representing atmospherically relevant biogenic and anthropogenic sources. The SOA and OPOA particles were generated via controlled exposure of precursors to OH radicals and/or O3 in a Potential Aerosol Mass (PAM) flow reactor over timescales equivalent to 1–20 days of atmospheric aging. Aerosol mass spectra of SOA and OPOA were measured with an Aerodyne aerosol mass spectrometer (AMS). The fraction of AMS signal at m/z = 43 and m/z = 44 (f43, f44), the hydrogen-to-carbon (H/C) ratio, and the oxygen-to-carbon (O/C) ratio of the SOA and OPOA were obtained, which are commonly used to characterize the level of oxidation of oxygenated organic aerosol (OOA). The results show that PAM-generated SOA and OPOA can reproduce and extend the observed f44–f43 composition beyond that of ambient OOA as measured by an AMS. Van Krevelen diagrams showing H/C ratio as a function of O/C ratio suggest an oxidation mechanism involving formation of carboxylic acids concurrent with fragmentation of carbon-carbon bonds. Cloud condensation nuclei (CCN) activity of PAM-generated SOA and OPOA was measured as a function of OH exposure and characterized as a function of O/C ratio. CCN activity of the SOA and OPOA, which was characterized in the form of the hygroscopicity parameter κorg, ranged from 0.003 to 0.28 over measured O/C ratios ranging from 0.05 to 1.42. This range of κorg and O/C ratio is significantly wider that has been previously obtained. To first order, the κorg-to-O/C relationship is well represented by a linear function of the form κorg = (0.17 ± 0.04) × O/C + 0.04, suggesting that a simple, semi-empirical parameterization of OOA hygroscopicity and oxidation level can be defined for use in chemistry and climate models.

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Cloud condensation nuclei activity of isoprene secondary organic aerosol

Journal of Geophysical Research Atmospheres ◽

10.1029/2010jd014706 ◽

2011 ◽

Vol 116 (D2) ◽

Cited By ~ 62

Author(s):

Gabriella J. Engelhart ◽

Richard H. Moore ◽

Athanasios Nenes ◽

Spyros N. Pandis

Keyword(s):

Secondary Organic Aerosol ◽

Cloud Condensation Nuclei ◽

Organic Aerosol ◽

Condensation Nuclei

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Gas-phase kinetics modifies the CCN activity of a biogenic SOA

Physical Chemistry Chemical Physics ◽

10.1039/c8cp00075a ◽

2018 ◽

Vol 20 (9) ◽

pp. 6591-6597

Author(s):

A. E. Vizenor ◽

A. A. Asa-Awuku

Keyword(s):

Particle Size ◽

Thermodynamic Properties ◽

Gas Phase ◽

Secondary Organic Aerosol ◽

Cloud Condensation Nuclei ◽

Organic Aerosol ◽

Aerosol Composition ◽

Phase Partitioning ◽

Gas Phase Kinetics ◽

Ccn Activity

Cloud condensation nuclei (CCN) activity and the hygroscopicity of secondary organic aerosol (SOA) depends on the particle size and composition, explicitly, the thermodynamic properties of the aerosol solute and subsequent interactions with water. The gas-to-aerosol phase partitioning is critical for aerosol composition and thus gas-phase vapors and kinetics can play an important role in the CCN activity of SOA.

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