Sk. Sali et al., SOLID-STATE REACTIONS OF URANIUM OXIDE AND ALKALI-METAL CHROMATES - CHARACTERIZATION OF NEW URANATES, Journal of nuclear materials, 217(3), 1994, pp. 294-299
Citations number
13
Categorie Soggetti
Nuclear Sciences & Tecnology","Mining & Mineral Processing","Material Science
New uranate phases, Rb2U4O11 and Rb2U3O8.5 in the Rb-U-O system and Na
2U3O9 and Na(y)U1-yO2-x (y = 0-0.2) in the Na-U-O system were prepared
and characterised by X-ray, thermal and chemical methods. Na(y)U1-yO2
-x was found to be a solid solution of Na2O in UO2 with fluorite struc
ture with a limited solid solubility of 10 mole% Na2O. These new phase
s reported could lead, in addition to the modification of the phase di
agrams, to a better understanding of the fuel-fission product-coolant-
clad chemical interactions. The new phases were identified during stud
ies on solid state reactions of chromates of caesium, rubidium, potass
ium and sodium with uranium oxides upto 1200-degrees-C in inert atmosp
here. These reactions have shown that different uranates are obtained
depending upon the O/U of the starting uranium oxide, with chromium se
parating as chromium oxide (Cr2O3).