ACETONE OXIDATION IN A PHOTOCATALYTIC MONOLITH REACTOR

Photocatalyzed oxidation of acetone (70-400 mg/m(3)) in air was carried out using near-UV illuminated TiO2 (anatase) coated on the surface of a ceramic honeycomb monolith. Considerable adsorption of acetone and water was noted on the catalyst coated monolith; these uptakes were described with a Langmuir adsorption isotherm for acetone and a modified BET adsorption isotherm for water. The acetone photocatalyzed disappearance kinetics on the TiO2 were determined with initial rate differential conversion, recycle reactor data and were analyzed using a Langmuir-Hinshelwood rate form coupled with a reactant mass balance including appreciable acetone monolith adsorption. The model, with parameters evaluated from initial rate data, is then shown to satisfactorily predict reactor behavior at all conversions. These kinetics and design results, together with earlier literature for photocatalytic oxidation of alkanes, 1-butanol, toluene, trichloroethylene, and odor compounds, indicate a potential for use of the photocatalytic monolith configuration for removal of all major classes of air contaminants. (C) 1994 Academic Press, Inc.