Laboratory measurement of absorption and oxidation of sulphur dioxide by zeolite

Two types of zeolite (Na–Y and H–Y) were exposed to air containing sulphur dioxide at varying conditions of relative humidity and temperature. We found that the amount of sulphate in the zeolite increased with increasing relative humidity and temperature. The rate and activation energy for the oxidation of sulphur dioxide to sulphate were determined for each experimental condition. The rate constant and activation energy increased as relative humidity decreased. These results can provide data which may be used to predict the amount of oxidation from sulphur dioxide to sulphate in the suspended clay particles in air and on soil surfaces, which is necessary to correctly understand sulphur fates on the earth.