Concerning uranate formation in alkali nitrate melts

The reaction of UO2 in molten alkaline nitrate has been studied by X-ray diffraction. Generally if sodium nitrate is present, up to 60 mol.%, 30 mol.% and 5 mol.% for sodium-lithium, sodium-potassium and sodium-cesium nitrate mixtures respectively, a solid solution is formed, which can be represented by the general formula Na2−xMexU2O7. Maximum solubilities have been determined. X-ray powder diffraction patterns for sodium diuranate, lithium mono- and diuranate are also given.