The role of oxidizing radicals in neptunium speciation in γ-irradiated nitric acid

The irradiation of aqueous nitric acid solutions generates transient, reactive species that are known to oxidize neptunium. However, nitrous acid is also a long-lived product of nitric acid irradiation, which reduces neptunium. When we irradiated nitric acid solutions of neptunium and measured its s...

Full description

Saved in:
Bibliographic Details
Published in:Journal of radioanalytical and nuclear chemistry 2013-04, Vol.296 (1), p.27-30
Main Authors: Mincher, Bruce J., Precek, Martin, Mezyk, Stephen P., Martin, Leigh R., Paulenova, Alena
Format: Article
Language:English
Subjects:
Chemistry
Chemistry and Materials Science
Diagnostic Radiology
free radicals
GENERAL AND MISCELLANEOUS
Hadrons
Heavy Ions
Inorganic Chemistry
neptunium
nitrous acid
Nuclear Chemistry
Nuclear Physics
Nuclear radiation
Physical Chemistry
radiation
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The irradiation of aqueous nitric acid solutions generates transient, reactive species that are known to oxidize neptunium. However, nitrous acid is also a long-lived product of nitric acid irradiation, which reduces neptunium. When we irradiated nitric acid solutions of neptunium and measured its speciation by UV/Vis spectroscopy, we found that at short irradiation times, oxidation of Np(V) to Np(VI) occurred due to reactions with radicals such as • OH, • NO 3 and • NO 2 . However, at higher absorbed doses and after a sufficient amount of nitrous acid was produced, reduction of Np(VI) to Np(V) began to occur, eventually reaching an equilibrium distribution of these species depending on nitric acid concentration. Neptunium(IV) was not produced.
ISSN:0236-5731
1588-2780
DOI:10.1007/s10967-012-1937-1