The photo catalytic oxidation of nitrobenzene, 2, 4,6-trinitrotoluene in aqueous suspensions of titanium dioxide (TiO2 Degussa type P25 was investigated. Under oxygen conditions, irradiation with the Pyrex-filtered out put of 15 W high pressure mercury-arc lamp resulted in complete (more 90 %) mineralization of 50 ppm of TNT, 30 ppm of NB within few hours. At the beginning irradiation, reduction by conduction band electrons may play a more significant role in the photo catalytic degradation of the studied mixtures. The resulted in aromatic ammine compounds were more easily to be oxidized by the hydroxyl radicals.
