Atmos. Chem. Phys. Discuss., 10, 15023-15054, 2010
© Author(s) 2010. This work is distributed
under the Creative Commons Attribution 3.0 License.
Review Status
This discussion paper has been under review for the journal Atmospheric Chemistry and Physics (ACP). Please refer to the corresponding final paper in ACP.
The effect of fatty acid surfactants on the uptake of ozone to aqueous halogenide particles
A. Rouvière and M. Ammann
Lab. for Radio and Environmental Chemistry, Paul Scherrer Institut, 5232 Villigen, Switzerland

Abstract. The reactive uptake of ozone to deliquesced potassium iodide aerosol particles coated with linear saturated fatty acids (C9, C12, C15, C18 and C20) as surfactants was studied. The experiments were performed in an aerosol flow tube at 293 K and atmospheric pressure. The uptake coefficient on pure deliquesced KI aerosol was γ=(1.10±0.20)×10−2 at 72–75% relative humidity. In presence of organic coatings, the uptake coefficient decreased significantly for long straight chain surfactants (>C15), while it was only slightly reduced for the short ones (C9, C12). We linked the kinetic results to the monolayer properties of the surfactants, and specifically to the phase state of the monolayer formed (liquid expanded or liquid condensed state). We also investigated the effect of organic films to mixed deliquesced aerosol composed of a variable mixture of KI and NaCl, which allowed determining the resistance exerted to O3 at the aqueous surface by the two longer chained surfactants pentadecanoic acid (C15) and stearic acid (C18). Finally, the effect of two-component coatings, consisting of a mixture of long and short chained surfactants, was also studied.

Citation: Rouvière, A. and Ammann, M.: The effect of fatty acid surfactants on the uptake of ozone to aqueous halogenide particles, Atmos. Chem. Phys. Discuss., 10, 15023-15054, doi:10.5194/acpd-10-15023-2010, 2010.
Search ACPD
Discussion Paper
    Final Revised Paper