A method has been developed for the extraction of uranium, neptunium and plutonium from human urine using the comparatively
cheap technical amine ALAMINE-336. These elements are coprecipitated with a calcium phosphate carrier, which is then subjected
to a wet-ashing procedure with NHO3/H2O2 and HCl/H2O2. The residue is dissolved in 10M hydrochloric acid and U, Np and Pu are extracted with a 10% ALAMINE-336/xylene solution,
followed by subsequent back-extraction with 10M HCl/NH4I (Pu), 4M HCl/HF (Np) and 0.1M HCl (U), respectively. The average recoveries are around 95%.