Analytical techniques for the transuranium elements ultratraces separation from depleted uranium ammunitions

It is well known that ammunition containing depleted uranium (DU) was used by NATO during the Balkan conflict. To evaluate the DU origin (natural uranium enrichment or spent nuclear fuel reprocessing) it is necessary to check the presence of activation products (236U, 239+240pu; 241Am, 237Np, etc.) in the ammunition. Every transuranium element (TRU) was separated from the uranium matrix by extraction chromatography with microporous polyethylene (lcorene) supporting suitable stationary phases. Plutonium was separated by tri-n-octylamine (TNOA). 241Am was separated by TNOA and di(2ethylhexylphosphoric) acid (HDEHP). Neptunium also was separated by tri-n-octylamine using different conditions. After elution, the TRU elements were electroplated and counted by alpha spectrometry. The TRU decontamination factors from uranium were higher than 106. The final chemical yields ranged from 50 to 70%. The detection limit was 1 Bq kg-1 for 0.10 g ammunition; 239+240Pu and 241Am concentrations in two penetrators were 26 and 70 Bq kg-1 and