Chemiluminescent redox reactions of uranyl

A chemiluminescence of UO22+ ions in redox reactions is studied. The ion UO22+ in electron-excited state acts, in some reactions, as an acceptor of yielded energy without changin.o. its valent state (UO22+ excitation at the oxidation of sulfur suspension by the ozone in the concentrated H2SO4). In other reactions the light emission completes the uranium redox reactions with UO22+ as their product (the reaction of uranium oxidation (4) by ozone and UO22+ ion reduction by europium (2)). The reaction of U4+ oxidation by ozone may be the basis for U4+ identification in the solution. In the presence of UO22+ ions a noticeable emission intensity is observed at 10-8 M of U4+ concentration. The luminescence arising at UO22+ ion reduction by two-valent europium is observed in darkness with the unaided eye. Rather large brightness arises due to a high reaction rate. Detailed schemes of the given reactions are considered, and their possible applications in the uranium analytical chemistry discussed