| 摘要 |
<p>Uranium is separated from thorium and protactinium by adding to an aqueous solution of their salts an organic salt of the formula <FORM:0809282/III/1> wherein R is alkyl, R1 is alkyl or aryl, and M is an alkali metal or alkaline earth metal. The corresponding organic uranyl compound is formed and is extracted from the aqueous solution. In a preferred procedure, thorium carbonate which has been irradiated with neutrons and contains small amounts of uranium and protactinium, is dissolved in nitric acid, brought to a pH of 2-3 by addition of ammonia, and then shaken with a solution of sodium diethyldithiocarbamate in amyl acetate. Uranyl diethyldithiocarbamate forms and dissolves in the organic layer. This layer is separated and uranium may be recovered therefrom by evaporating the solvent, heating the residue to form uranium oxide, dissolving this in acid, and removing thorium by precipitation as fluoride. Other suitable organic solvents are methyl isobutyl ketone, diethyl ketone, methyl n-propyl ketone, and dibutoxytetraethylene glycol. Before treatment with the organic salt solution, protactinium may be removed from the nitrate solution by adsorption on manganese dioxide.ALSO:In the separation of uranium from thorium and protactinium (see Group III), an aqueous solution of their salts is reacted with an organic salt of the formula <FORM:0809282/IV (b)/1> wherein R is alkyl, R1 is alkyl or aryl, and M is an alkali metal or alkaline earth metal. The corresponding organic uranyl salt, e.g. uranyl diethyldithiocarbamate, is formed and is extracted with a water-immiscible organic solvent, e.g. amyl acetate.</p> |
