Method of seperation between uranium and plutonium

摘要

A method for selectively reducing tetravalent plutonium dissolved in an aqueous solution or organic solvent solution together with hexavalent uranium, which comprises adding isobutyraldehyde to said solution. Separation between uranium and plutonium in nuclear fuel reprocessing can be carried out by adding isobutyraldehyde to an extract of tetravalent plutonium and hexavalent uranium in a TBP solvent, and back extracting the trivalent plutonium thus produced into a nitric acid solution. Isobutyraldehyde also acts to remove nitrous acid from the nitric acid to prevent re-oxidation of the trivalent plutonium, and its oxidation product, butyric acid, is readily decomposed.