Destructive Photosorption of Halogen-Containing Organic Compounds by the Components of Solid Atmospheric Aerosol under Tropospheric Conditions
VALERY S. ZAKHARENKO and VALENTIN N. PARMON
G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: zakh@catalysis.nsk.su
Pages: 671-678
Abstract
The results of investigation of the interaction of halogen-containing organic compoungs (HOCs) with magnesium, aluminium and silicon oxides of industrial and laboratory preparation in the dark and under the action of sunlight in the troposphere are presented. The chemical composition of these oxides corresponds to the main components of solid atmospheric aerosol. The experimental results are the evidence that fluorine- and chlorine-containing organic compounds containing also hydrogen atoms are destructively photosorbed on MgO exposed for a long time in the air, magnesium halides being formed as a result of photosorption. The rate of photosorption for fluorine-containing hydrocarbons is several times higher than that for chlorine-containing hydrocarbons. The amount of hydrochlorofluorocarbons (HCFCs) photosorbed at room temperature and pressure of 1 Pa can exceed 15 % of the monolayers of MgO surface. The interaction of magnesium oxide with HCFCs leads to their removal from the atmospheric air under tropospheric conditions till the residual HCFC pressure less than 10
|
