Plutonium is recovered from aqueous solution by extraction with a solution of trilaurylamine in an organic solvent, transfer to the aqueous phase by contacting with sulphuric acid or a mixture of sulphuric and nitric acids, addition of oxalic acid to precipitate plutonium oxalate, and recycling the precipitation mother liquor to the trilaurylamine extraction stage. If the oxalic acid concentration of the mother liquor is above 0À24 N, ferric nitrate is added to prevent precipitation of plutonium oxalate. The original plutonium-containing solution may be derived from the dissolution of nuclear fuels or plutonium slags obtained by reduction of plutonium fluoride by an alkaline earth metal.
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