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Atmos. Chem. Phys. Discuss., 5, 5645-5667, 2005
www.atmos-chem-phys-discuss.net/5/5645/2005/ doi:10.5194/acpd-5-5645-2005 © Author(s) 2005. This work is licensed under a Creative Commons License. |
Kinetics and mechanism of the uptake of N2O5 on mineral dust at 298 K
1Institute for Physical and Theoretical Chemistry, University Duisburg-Essen, Germany
2Ford Forschungszentrum Aachen, Aachen, Germany
Abstract. The heterogeneous reaction of N2O5 with mineral (Saharan) dust has been studied at T=298 K using a combination of Knudsen and DRIFTS cell for kinetic and product investigations, respectively. The initial uptake coefficient has been determined to be γ=(8.0±0.3)·10−2. This uptake slowly saturates into a steady state uptake of γ=(1.3±0.3)10−2 suggesting that reaction of N2O5 with the mineral dust surface and hydrolysis of N2O5 on the surface take place simultaneously. Moreover, the product investigations suggest that N2O5 is irreversibly taken up forming nitrate on the surface. The uptake rates of N2O5 on Saharan dust are large enough to influence the photo-oxidant budget of the atmosphere.
Citation: Seisel, S., Börensen, C., Vogt, R., and Zellner, R.: Kinetics and mechanism of the uptake of N2O5 on mineral dust at 298 K, Atmos. Chem. Phys. Discuss., 5, 5645-5667, doi:10.5194/acpd-5-5645-2005, 2005.