Photocatalytic mineralization of 2,4,6-trinitrotoluene in aqueous suspensions of titanium dioxide

The photocatalytic destruction of 2,4,6-trinitrotoluene (TNT) in aqueous suspensions of titanium dioxide (TiO2, Degussa type P25) was investigated. Under aerobic conditions, irradiation with the Pyrex-filtered output of a 200-W high pressure mercury-arc lamp resulted in complete (95 ± 5%) mineralization of 50 ppm of TNT within a few hours. Rapid photodegradation of TNT also occurred under anaerobic conditions but without appreciable mineralization. In the absence of TiO2, direct photolysis of TNT yielded a complex mixture of colored organic products in both aerobic and anaerobic environments.