Photochemical oxidation of Np(IV) and Pu(IV) in carbonate solutions saturated with N{sub 2}O
- Inst. of Physical Chemistry, Moscow (Russian Federation)
Photooxidation of Np(IV) and Pu(IV) in carbonate and bicarbonate solutions under UV irradiation of a mercury lamp was studied. In deaerated solutions Np(IV) is slowly oxidized to Np(VI), while Pu(IV) is stable. The rate of Np(IV) photooxidation sharply increases after saturation of solution with N{sub 2}O, and complete conversion of Np(IV) (1 x 10{sup -4} M) into Np(VI) is reached within 2.5 h. The reaction is efficient at pH 8.4-12.0. Under irradiation of Pu(IV) solutions saturated with N2O, Pu(VI) is formed only at pH 11-12. Under these conditions, the complete oxidation of Pu(IV) to Pu(VI) is possible. The influence of other factors on Np(IV) and Pu(IV) photooxidation and mechanisms of reactions were considered. The rate constants for Np(IV) reaction with CO{sub 3}{sup -} radicals were estimated.
- OSTI ID:
- 224061
- Journal Information:
- Radiochemistry, Journal Name: Radiochemistry Journal Issue: 6 Vol. 37; ISSN RDIOEO; ISSN 1066-3622
- Country of Publication:
- United States
- Language:
- English
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