Photocatalytic oxidation of Auramine O in the presence of semiconducting oxides

The photocatalytic degradation of Auramine O, a diarylmethane fluorescent d ye, has been investigated in aqueous heterogeneous solutions containing sem iconductor oxides as photocatalysts. The disappearance of the organic molec ule follows approximately a pseudo-first order kinetics according to the La ngmuir-Hinshelwood model. CO2 and NH4+ ions have been identified as mineral ization products. Various commercial photocatalysts are compared with respe ct to their decolorization efficiency, as well as the production of CO2. Th e effect of pH and H2O2 on the reaction rate is ascertained. (C) 2000 Socie ty of Chemical Industry.