Neptunium nitrate solution. Neptunium TiOA - TTA method. Revision 1

An analytical solvent extraction method for separating neptunium from plutonium, americium, curium, uranium, thorium, and fission products using tri-iso-octylamine (TiOA) and thenoyltrifluoroacetone (TTA) is described. Neptunium is separated from the bulk of the plutonium, americium, curium, and fission products by the extraction of neptunium(IV) into RiOA, dissolved in xylene, from an aqueous nitric acid reducing solution. The neptunium bearing organic solution is then scrubbed with a nitric acid reducing solution to achieve further purification. Final purification is obtained by stripping neptunium from tri-iso-octylaminexylene solution into dilute hydrochloric acid and then extracting the neptunium(IV) into TTA dissolved in xylene. A quantitative neptunium measurement is then made by alpha counting and alpha pulse height analysis. Most of the neptunium bearing sample solutions associated with the chemical processing of irradiated uranium are aqueous nitric acid solutions, and with the exception of uranium(IV) are free from interfering materials.