Spectroscopic and redox studies of actinides in high ionic strength solutions
- Los Alamos National Lab., NM (United States)
The redox behavior of pure oxidation states of environmentally relevant actinides (U, Np, Pu) in high ionic strength solutions at near neutral pH conditions are not well known. It is expected that relatively reducing conditions will be present in many geological waste disposal sites, and such conditions have important implications for the leachability of radioactive wastes into the environment. Millimolar concentrations of actinide ions in several oxidation states (U(VI), Np(VI), Pu(III), (IV), (V), (VI)) were prepared and the absorbtion spectra obtained in high ionic strength solutions by UV-Vis-NIR and/or photoacoustic spectroscopy. Spectroscopic results indicate that actinyl species have greater solubility under such conditions due to complexation by chloride ions. Actinyl carbonate and chloride complexes were prepared in high ionic strength solutions (approx. 5M) and the redox reactions monitored by UV-Vis-NIR spectroscopy after exposure to a variety of inorganic reducing reagents (Fe{sup 0}, Fe{sub 2+}, S{sup 2-}, H{sub 2}). Several reducing agents were shown to be effective at limiting the solubility of the Pu(VI) complexes. These results will be discussed along with results of ongoing experiments.
- OSTI ID:
- 538954
- Report Number(s):
- CONF-960807-; TRN: 97:004029-0021
- Resource Relation:
- Conference: 212. national meeting of the American Chemical Society (ACS), Orlando, FL (United States), 25-30 Aug 1996; Other Information: PBD: 1996; Related Information: Is Part Of 212th ACS national meeting; PB: 1830 p.
- Country of Publication:
- United States
- Language:
- English
Similar Records
ACTINIDE-ALUMINATE SPECIATION IN ALKALINE RADIOACTIVE WASTE
Spectroscopic and structural studies of environmentally relevant Neptunium(V) and Plutonium(V) complexes