Fluidized-bed photocatalytic oxidation of trichloroethylene in

1 h on stream time to develop their maximumphoto- catalytic oxidation activity. Steady-state reaction rates as high as 0.8 µ of TCE (g of catalyst)"1...
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Environ. Sci. Technol. 1992, 26, 492-495

Fluidized-Bed Photocatalytic Oxidation of Trichloroethylene in Contaminated Airstreams Lynette A. Dlbblet and Gregory B. Raupp" Department of Chemical, Bio & Materials Engineering, Arizona State University, Tempe, Arizona 85287-6006

Gas-solid heterogeneous photocatalytic oxidation of trichloroethylene (TCE) in humid airstreams is achieved at high conversion levels in a bench-scale flat-plate fluidized-bed photoreactor, which provides efficient continuous contact of near-ultraviolet photons, silica-supported titania photocatalyst, and gaseous reactants. Silica-supported titania catalysts prepared through sol-gel methods require -1 h on stream time to develop their maximum photocatalytic oxidation activity. Steady-state reaction rates as high as 0.8 pmol of TCE (g of catalyst)-l min-' [2 pmol (g of TiO,)-l min-l] and quantum efficiencies of 13% have been achieved over conditioned catalysts. High conversion of dilute levels (