JRP 02-25

Partners

CNRS

logo CIEMAT

CEA

Contact

Prof. Dr. B. Grambow
SUBATECH/CNRS - 4 rue Alfred Kastler - 44307 Nantes - France
Phone + 33 (0) 251 85 84 70
E-mail e-mail

Coprecipitation of radionuclides with UO2 under anoxic and/or reducing conditions

Status

 
Terminated - Planned from April 2005 till October 2006

Goals

The aim of this joint research project is to integrate and coordinate the existing work concerning coprecipitation processes for actinides and other radionuclides from aqueous solutions. In particular, the following systems will be studied:

  • coprecipitation of minor fractions of ThO2, Nd2O3, Gd2O3, La2O3, Eu2O3 in UO2;
  • solid solution formation during spent fuel dissolution under reducing conditions.

The main objective is to develop solid solution models that can be integrated into geochemical codes. These models will allow the prediction of coprecipitation behaviour of radionuclides, and account for pH dependent non-ideality, solid phase oxidation state and cristallinity dependent endmember solubility.

Expected results

The results of this joint research project will contribute to the control of radionuclides (from aqueous solutions) in nuclear waste repositories. Furthermore, the fabrication of Nd and Gd doped UO2 will lead to more homogeneous material (monodispers particle size) for the oxidation studies of UO2.

Presentations

  • Rousseau G., Desgranges L., Boucher F., Ouvrard G., Fattahi M., Grambow B., Niepce J.C..- Synthèse et caractérisation des poudres nanométriques de UO2- Colloque « Poudres et Matériaux Frittés 2005 »: Cherbourg, France, May 18-20, 2005
  • Rousseau G., Fattahi M, Grambow B., Boucher F. and Ouvrard G..- Coprecipitation of thorium and lanthanum with UO2+x(s) as host phase. 10th international conference on chemistry and migration behavior of actinides and fission products in the geosphere (Migration 2005): Avignon, France, September 18-23, 2005

Reports