Heterogeneous ozonation kinetics of phenanthrene at the air–ice interface

• Published in: Environmental research letters Vol. 3; no. 4; pp. 045006 - 045006 (6)
• Main Authors: Kahan, T F, Donaldson, D J
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.10.2008
• Subjects: Air-ice interface; Fluorescence; Ice; Kinetics; Laser induced fluorescence; Ozonation; Phenanthrene; Physical properties; Self-association; Temperature dependence; Water
• ISSN: 1748-9326; 1748-9326
• DOI: 10.1088/1748-9326/3/4/045006

Phenanthrene ozonation kinetics were measured on ice at −30 and −10 °C, and on a water surface at 22 °C using glancing angle laser-induced fluorescence. A Langmuir–Hinshelwood type kinetic mechanism was observed on ice. The maximum ozonation rates were a factor of ten higher on ice than on water. No temperature dependence to the kinetics was observed between −30 and −10 °C, suggesting that the differences in the rates on ice and water are due to different physical properties at the two surfaces. Fluorescence spectra of phenanthrene show significant self-association on ice that is not observed on water, adding further evidence for the hypothesis that the quasi-liquid layer at the air–ice interface presents a very different environment to liquid water.