| 摘要 |
A method of purifying uranium-containing substances containing compounds of one or more of the metals aluminium, magnesium, calcium and iron by removing the uranium from said substances. The purification is effected by selective, alkaline carbonate leaching of the uranium. The substance is finely divided and slurried in an aqueous solution containing 0.3-1.5 mole/l of carbonate ions and having an oxidation potential of 0.3-1 V, and subsequent to the leaching process the leaching liquid has a pH of between 8.5 and 10.5 at a pressure of 0.2 to 2.0 MPa. The substance may be finely-divided by wet-grinding, and the leaching solution used as the grinding liquid. The leaching is preferably effected in a tube reactor vessel in which the substance is slurried in leaching liquid at a temperature of 120-180 DEG C and leached at a partial pressure of oxygen of 0.1-0.6 MPa. |
