GB802452A - Improvements in a method of recovering uranium from ores containing it - Google Patents

Abstract

Hydrated uranium dioxide is recovered by precipitation with nascent hydrogen from a solution of a hexavalent uranyl-alkali metal or -ammonium carbonate solution obtained from a uranium ore. The solution may be obtained, e.g. by directly leaching the ore with sodium carbonate or bicarbonate (with an oxidizing agent if necessary) or by treating with an excess of sodium carbonate the product of acid leaching (with an oxidizing agent if necessary). In examples, the former method is used, the leaching being performed at 70 DEG or 80 DEG C. The nascent hydrogen is preferably generated by electrolysis of the solution (see Group XXXVI) in the presence of a hydrogenation catalyst such as nickel, platinum, palladium, iron or mercury or alloys thereof such as an aluminium/nickel alloy. The catalyst may be finely divided and used as a suspension or may be in the form of a fine grid, preferably located close to the cathode. After removal of the hydrated uranium oxide, the solution can be reused to attack further quantities of the ore. A nickel catalyst, if used, may be separated from the precipitate magnetically.