Abstract View
Photolysis of Aqueous Atmospheric Aerosol Mimics
Jacqueline Sharp, Daisy Grace, Shiqing Ma, Joseph Woo, MELISSA GALLOWAY, Lafayette College
Abstract Number: 386
Working Group: Aerosol Chemistry
Abstract
Aqueous reactions of small, water soluble aldehydes with amines or ammonium salts are important contributors to atmospheric brown carbon formation processes. The extent to which photolysis of these brown carbon compounds changes the chemical composition and light absorption of these systems is not well understood or characterized. We photolyze aged reaction systems of aqueous carbonyls (e.g., glycolaldehyde, glyoxal, methylglyoxal, and hydroxyacetone) and ammonium sulfate and monitor light absorption and chemical composition via UV-visible spectroscopy and supercritical fluid chromatography–tandem mass spectrometry. Photobleaching and photobrowning rates vary with wavelength and aldehyde identity, while mass spectrometry shows that the chemical composition changes significantly upon photolysis.