Removal of indoor contaminants by photocatalytic reaction

The reduction of indoor air pollutants by air cleaning systems has received considerable interest and a number of techniques are now available. So far, the method of photocatalysis was mainly applied by use of special flow reactors under UV light of high intensity. Nowadays, typical indoor wall paints are equipped with modified TiO2 to work as a catalyst under indoor daylight conditions. In this case the reaction rate is a function of the contact between the molecule and the catalytic surface. Brownian motion and residence time. In chamber experiments it was shown that the method works well for nitrogen dioxide (NO2) under dynamic conditions and for formaldehyde under static conditions. When the chamber was spiked with carbon monoxide (CO) or typical VOCs like 1,2-dichlorobenzene under dynamic conditions, no significant effect could be observed.