Issue 34, 2006

The heterogeneous kinetics of HOBr and HOCl on acidified sea salt and model aerosol at 40–90% relative humidity and ambient temperature

Abstract

The HOBr and HOCl uptake coefficient γ on H2SO4-acidified submicron salt aerosol of known size distribution was measured in an atmospheric pressure laminar flow reactor. The interaction time of the trace gas with the aerosol was in the range 15 to 90 s and led to γ values in the range 10−4 to 10−2. The acidity of the aerosol is essential in order to enable heterogeneous reactions of HOBr on NaCl, recrystallized sea salt (RSS) and natural sea salt (NSS) aerosols. Specifically, HOCl only reacts on acidified NSS aerosol with a γ ranging from 0.4 × 10−3 to 1.8 × 10−3 at a relative humidity (rh) at 40 and 85%, respectively. Uptake experiments of HOBr on aqueous H2SO4 as well as on H2SO4-acidified NaCl, RSS or NSS aerosol were performed for rh ranging from 40 to 93%. The γ value of HOBr on acidified NSS reaches a maximum γ = 1.9 × 10−2 at rh = 76 ± 1% and significantly decreases with increasing rh in contrast to acidified NaCl and RSS aerosols whose γ values remain high at γ = (1.0 ± 0.2) × 10−2 at rh ≥ 80%. An explanation based on the formation of an organic coating on NSS aerosol with increasing rh is proposed.

Graphical abstract: The heterogeneous kinetics of HOBr and HOCl on acidified sea salt and model aerosol at 40–90% relative humidity and ambient temperature

Article information

Article type
Paper
Submitted
24 Mar 2006
Accepted
04 Jul 2006
First published
20 Jul 2006

Phys. Chem. Chem. Phys., 2006,8, 3988-4001

The heterogeneous kinetics of HOBr and HOCl on acidified sea salt and model aerosol at 40–90% relative humidity and ambient temperature

P. Pratte and M. J. Rossi, Phys. Chem. Chem. Phys., 2006, 8, 3988 DOI: 10.1039/B604321F

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements