Industrial & Engineering Chemistry Research, Vol.38, No.9, 3211-3217, 1999
Novel photocatalytic reactor for the destruction of airborne pollutants reaction kinetics and quantum yields
Photocatalytic conversion of a model pollutant (toluene) is studied in a newly designed batch photoreactor, called Photo-CREC-Air. In this unit TiO2 is supported on a filter mesh with good contact with near UV light, TiO2, and air. Photo-CREC-Air is designed with special features including a Venturi section and a heated perforated plate. The heated perforated plate minimizes water adsorption on the mesh and consequently water effects on the reaction rate. The system performance is examined for different toluene concentrations and two humidity levels. After assessing the insignificant toluene adsorption observed under the selected operating conditions, a pseudohomogeneous model is postulated for kinetics modeling. Initial photodegradation rates of toluene at 100 degrees C in Photo- CREC-Air, in the range of model pollutant concentrations and humidity level studied, were 0.005-0.05 mu mol/(gcat s). Apparent quantum yields were estimated to be in many cases greater than 100% and as high as 450%.
Keywords:GAS-PHASE;CABLE REACTOR;OXIDATION;TRICHLOROETHYLENE;AIR;DEGRADATION;TOLUENE;FORMALDEHYDE;CATALYST;ACETONE