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| author | Jed-Joan S Edziah |
| title | Secondary Aerosol Formation from Heterogeneous Reactions Involving α-(+)-Pinene and Kaolinite |
| abstract | Secondary organic aerosols (SOA) are an abundant class of atmospheric particulates that impact climate, human health,
and atmospheric chemistry. While there is extensive research on gas-phase chemistry that converts volatile organic compounds to less volatile SOA components,
heterogeneous pathways in which low volatility organic SOA components are produced from direct reactions of volatile organic compounds with mineral dust
aerosols are not well characterized. To better understand this heterogeneous chemistry, we used diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS)
to monitor the formation of surface-adsorbed organic products from heterogeneous reactions between gaseous (α)-(+)-pinene and kaolinite clay at various
relative humidity levels. Gas chromatography and mass spectrometry identified α-terpineol, fenchol, endoborneol and high molecular weight dimers, which
significantly increase SOA quantity and mass, as the major organic products. The rate of organic product formation inversely correlated with the relative
humidity level indicating that H2O(g) molecules compete with α-pinene molecules for surface sites on kaolinite. Using a laminar
flow reactor, the uptake coefficient for reactions between α-pinene and kaolinite was calculated to be 1.6x10-6. Kinetic and product analyses
suggest that the reaction between kaolinite and (α)-(+)-pinene leads to the formation of lower volatility organics that promote SOA production. |
| school | The College of Liberal Arts, Drew University |
| degree | B.A. (2017) |
| advisor | Dr. Ryan Z. Hinrichs |
| committee | Dr. Mary-Ann Pearsall
Dr. Robert Murawski |
| full text | JSEdziah.pdf |
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