Characterization of a Uranium Ore Concentrate Sample Interdicted in - PDF document

12/18/2016 Characterization of a Uranium Ore Concentrate Sample Interdicted in Durban, South Africa Radiation Measurement Cross Calibration Workshop December 2016 LLNL-PRES-655302 This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. Lawrence Livermore National Security, LLC  South Africa police seized a shopping bag containing ~1 kg of a uranium- rich material in a “sting” operation  Two individuals arrested  Material analyzed by Necsa • Uranium ore concentrate, depleted in 235 U: 0.38% 235 U  10 g aliquot transferred to LLNL in December 2013 under the MOU describing cooperation in nuclear forensics between South Africa and the United States  Kobus Hancke visited LLNL in January 2014 to participate in the analyses Lawrence Livermore National Laboratory 2 LLNL-PRES-592885 1

12/18/2016  Gamma ray spectroscopy  X-ray diffraction  X-ray fluorescence  Optical spectroscopy  Scanning electron microscopy  Davies-Gray titration  Inductively-coupled plasma mass spectrometry (ICP-MS)  Thermal ionization mass spectrometry (TIMS) Lawrence Livermore National Laboratory 3 LLNL-PRES-592885 Lawrence Livermore National Laboratory 4 LLNL-PRES-592885 2

12/18/2016 Lawrence Livermore National Laboratory 5 LLNL-PRES-592885 Lawrence Livermore National Laboratory 6 LLNL-PRES-592885 3

12/18/2016 Lawrence Livermore National Laboratory 7 LLNL-PRES-592885 Radionuclide abundances in the Durban UOC Concentration Concentration (at. %) 1 Radionuclide (atoms) 95 Zr <1.23 x 10 7 106 Ru <1.85 x 10 9 125 Sb <3.69 x 10 8 137 Cs <1.85 x 10 9 144 Ce <3.69 x 10 8 155 Eu <3.69 x 10 8 234 U (1.020 ± 0.20) x 10 -3 235 U 0.333 ± 0.001 238 U 99.67 ± 0.20 1. Uncertainties are 2 standard deviations Lawrence Livermore National Laboratory 8 LLNL-PRES-592885 4

12/18/2016 Ammonium Uranium Fluoride (NH 4 ) 2 UF 6 Uranium Oxide Ammonia Hydrate 2UO 3 ·NH 3 ·3H 2 O Ammonium Uranium Oxide Hydrate UO 3 ·NH 3 ·H 2 O Ammonia Uranium Oxide Hydrate UO 3 ·yNH 3 ·xH 2 O Lawrence Livermore National Laboratory 9 LLNL-PRES-592885  Davies-Gray titration yields a U-content of 74.9 ± 0.5 wt.%  Compares to 67.5 wt.% measured by Necsa  Total impurity content of ~300 mg/g  Major impurities are Na, K, Ca, Fe, Mo and Cs Lawrence Livermore National Laboratory 10 LLNL-PRES-592885 5

12/18/2016 Abundance Abundance Isotope Uncertainty (pg/g) (at.%) 234 U 0.002111 0.000007 235 U 0.3196 0.0002 236 U 0.01844 0.00007 238 U 99.664 0.002 239 Pu 9.7 ± 0.5 92.81 240 Pu 0.0981 0.004 Lawrence Livermore National Laboratory 11 LLNL-PRES-592885 Lawrence Livermore National Laboratory 12 LLNL-PRES-592885 6

12/18/2016  Modeled a graphite moderated, natural uranium (NU) fueled reactor using the MAGNOX reactor model included in the Origen-ARP component of SCALE 6.1  NU fuel irradiated for ~100 days to a burnup of 1.6 240 Pu content of ~14% at GWD/MTU would have a discharge  Using this fuel as feed for an enrichment cascade 235 U enriched to 2%, the ORNL MSTAR producing program calculates 234 U / 235 U = 9.1 x 10 -3 and 236 U / 235 U = 4.2 x 10 -2 , both values consistent with measurements Lawrence Livermore National Laboratory 13 LLNL-PRES-592885  The UOC is ammonium uranyl fluoride plus two hydrated uranyl oxides  Total impurity content of ~300 mg/g  Major impurities are Na, K, Ca, Fe, Mo and Cs  The UOC is depleted in 235 U with a 235 U/ 238 U ratio ~2x lower than that of natural uranium (NU)  The elevated 236 U content indicates the parent material was irradiated in a nuclear reactor  The UOC likely originated as NU fuel irradiated in a graphite-moderated reactor and used as feedstock for an enrichment cascade Lawrence Livermore National Laboratory 14 LLNL-PRES-592885 7

12/18/2016 Acknowledgements The LLNL/NECSA nuclear forensics team: Rachel E. Lindvall Lars Borg Naomi Marks Amy M. Gaffney Reuben P. Mogafe Victoria G. Genetti Aubrey N. Nelwamondo Patrick M. Grant Christina E. Ramon Kobus J. Hancke Erick C. Ramon Ian D. Hutcheon Martin Robel Theresa M. Kayzar Michael A. Sharp Gregory L. Klunder Michael J. Singleton Kim B. Knight Ross W. Williams Michael J. Kristo Work supported by NNSA’s Office of Defense Nuclear Nonproliferation and the South African Nuclear Energy Corporation Lawrence Livermore National Laboratory 15 LLNL-PRES-592885 8