TiO₂ photocatalytic oxidation: III. Gas-phase reactors

A number of photocatalytic reactors with different configurations of supported and pelleted photocatalysts was studied. In a coaxial cylindrical reactor with an axially arranged lamp, the productivity of air purification increased in the order of photocatalyst carriers: reactor walls, quartz capillaries, quartz cullet, and metal gauze. A reactor with a vibrationally fluidized bed of a pelleted photocatalyst provided an opportunity to improve the quantum efficiency of acetone oxidation, as compared with a fixed bed, because of the effect of periodic illumination of the photocatalyst surface. A reactor with a photocatalyst supported on the inner surface of a Pyrex coil made it possible to repeatedly reactivate the photocatalyst at regular intervals by washing with water after deactivation in the oxidation of organic sulfides. Membranes of porous glass and porous organic photocatalyst carriers provided good contact of air (at a flow rate of about tens of cubic meters per hour) and light with the catalyst.