Ozone destruction on solid particles

Abstract

Ozone (O3) is an important constituent of the Earth atmosphere, either stratosphere, where it has a beneficial role to protect Earth's surface from harmful UV-B radiation, or troposphere where it is considered an air pollutant. We investigated the ozone destruction on solid particles of natural or anthropogenic origin as: silica-gel, pollen, coal fly ash, titanium dioxide with different specific surface (s) and sodium halides (NaCl, NaBr and NaI). The experiments were conducted in a fluidized bed reactor with elevated ambient concentrations of O3 (100 ppb) employed. The results indicate that the destruction of O3 depends upon: sample quantity (silica-gel with equal s), sample surface (TiO2 with different s) and chemical composition (coal fly ash comparative to wood ash). Interesting results were obtained with sodium halides: no effect on O3 concentrations was detected with NaCl, NaBr shows a certain destruction, while NaI removes completely O3 from the air stream. In the experiments with NaI doped NaCl, the destruction of O3 was dependent on NaI quantity.