PHOTOCATALYTIC TREATMENT OF LABORATORY WASTES CONTAINING AROMATIC-AMINES

The photocatalytic degradation of several aniline derivatives present in aqueous solutions containing TiO2 suspensions was investigated. The process leads to the complete and fast decomposition (within about 1 h) of the pollutant molecules, promoted by oxidizing radical species f ormed at the irradiated semiconductor/water interface. The stoichiomet ric formation of CO2 from the organic carbon was assessed, whereas oth er inorganic end-products were detected depending on the nature of the aniline substituents. Unstable hydroxyaromatic intermediates were als o identified during the initial steps of the treatment. The primary de gradation, which follows pseudo-first-order kinetics, changes with the aniline substituents and is strongly dependent on pH.