Abstract
During a photo-induced catalytic reaction under near UV irradiation to an aqueous suspension of TiO2, about 95% of NO2- was oxidized to NO3-, but NH4+ was not detected. The oxidation was inhibited by the addition of mannitol or under anaerobic conditions. The nitration of HPA was observed in the presence of t-buthanol, suggesting the formation of ONOO-. An ESR spectrum gave a triplet signal at g=2.041, in the presence of NO2-, mannitol, FeSO4, and MGD, indicating the reduction of NO2- to NO.