HETEROGENEOUS PHOTOCATALYSIS FOR CONTROL OF VOLATILE ORGANIC-COMPOUNDS IN INDOOR AIR

Research results concerning the photocatalytic activity and selectivit y of benzene are discussed. This compound, which represents one of an important class of volatile organic compounds found in indoor air, was oxidized in an annular photocatalytic reactor featuring a thin film o f titanium dioxide and illuminated by a fluorescent black light. The g as phase products, carbon dioxide and carbon monoxide, were quantified with a Fourier transform infrared spectrometer (FTIR). Adsorbed inter mediates were extracted from the surface with water. The extract was a nalyzed via high performance liquid chromatography and some of the ads orbed species were provisionally identified by retention time matching . The adsorption of reactants on the catalyst surface was studied expl icitly, particularly with respect to the effect of near-UV radiation o n adsorption processes. Maximum and steady-state rates of the surface reactions are reported here as functions of the operating conditions. Deactivation of the catalyst surface is characterized and methods of r egeneration of catalyst activity are explored. This established resear ch methodology provides the framework for a broader outline of researc h into enhancement of indoor air quality via photocatalytic oxidation. The results of investigations are discussed that pertain to a variety of classes of compounds representative of indoor air pollutants.