Process for purification, partitioning and recovery of plutonium

An aqueous feed having a suitable concentration of plutonium or its mixture with uranium and americium or other impurity materials in a nitric acid solution is prepared for the solvent extraction portion of the process. The organic phase consists of a solution of tributyl phosphate (TBP) and diluent, for example n-dodecane. Plutonium and uranium are taken into the organic phase and americium or other impurity materials remain in the aqueous phase. The loaded organic phase goes through a number of scrubbing stages. The loaded TBP is diluted and contacted with an oxalic and nitric acid mixture solution for back-extraction and precipitation of plutonium from the TBP phase into the aqueous phase. The plutonium oxalate precipitate is obtained as pure plutonium or as a co-precipitate with a small quantity of uranium. (P.D.R.)