Surface Properties of Metal Hydroxide Microparticles in the Ambient Air

Abstract

Abstract. The adsorption and photoadsorption properties of Mg(OH) 2 and Ca(OH) 2 microparticles in the ambient air were investigated. The compositional analysis of an adsorption layer of microparticles was carried out. The kinetics of photodesorption of molecules from microcrystal surfaces and the interaction of HCFC-22 (CHF 2 Cl) in the dark and under light were studied. Quantum yields and their spectral dependencies were determined for CO 2 photodesorption, O 2 and CO photoadsorption. The effect of weakly bound CO displacement from the surface of microparticles was revealed during dark adsorption of HCFC-22. It is supposed that adsorbed CO is formed as a result of atmospheric CO 2 reduction after the break of Mg-OH bonds. In case of calcium hydroxide, CO is generated during the interaction of calcium hydroxide with carbon dioxide in the presence of water.