Oxidation of variable-valence cations with ozone: II. Selection of a cation catalyzing oxidative dissolution of plutonium oxide

Citation
Gp. Nikitina et al., Oxidation of variable-valence cations with ozone: II. Selection of a cation catalyzing oxidative dissolution of plutonium oxide, RADIOCHEMIS, 41(6), 1999, pp. 538-544
Citations number
24
Categorie Soggetti
Inorganic & Nuclear Chemistry
Journal title
RADIOCHEMISTRY
ISSN journal
10663622 → ACNP
Volume
41
Issue
6
Year of publication
1999
Pages
538 - 544
Database
ISI
SICI code
1066-3622(199911/12)41:6<538:OOVCWO>2.0.ZU;2-F
Abstract
Main features of reactions of variable-valence cations Mn+ [Mn+ = Ag(I), Ru (IV), Ce(III), TI(I), Np(IV, V), Pu(IV)] with ozone in nitric acid solution s were studied. The kinetic parameters of reaction of Np(IV) and Pu(IV) wit h O-3 in a wide range of reaction conditions were determined. The mechanism of intraspheric oxidation involving formation of outerspheric complex of t he ion being oxidized with ozone (Mn+ <--OH2... O-3) with subsequent substi tution of intraspheric water molecule with ozone or detachment of the hydro gen atom from the hydrate water molecule to form Mn+<--OH and HO3 was propo sed. Plutonium(IV) is most likely to be oxidized with ozone via formation o f Pu4+<--O-3 complex. Ag(I), Ce(III), and Co(II) were chosen as catalysts o f dissolution of PuO2 by its oxidation with ozone.