DOI QR코드

DOI QR Code

Uranium tetrafluoride production at pilot scale using a mercury electrode cell

  • Received : 2021.09.10
  • Accepted : 2021.11.14
  • Published : 2022.05.25

Abstract

This work shows the technical feasibility to obtain uranium tetrafluoride through an electrochemical mercury cell. This technique represents a custom scaling-up methodology from our previous studies to obtain UF4 using the dropping mercury electrode cell. The UF4 products were obtained from natural UF6 gas, which was hydrolyzed to obtain a 50 g/L UO2F2 solution. The electrolysis cell was made using a mercury reservoir, to reach UF4 production rates of 1 Kg UF4/day. This custom design allowed a stable UF4 production thanks to the mercury cathode, which do not permit the accumulation of solid products in its surface. The cell was tested using current densities from 5.000 to 17.500 A/m2 and temperatures from 25 to 65 ℃. The maximum current efficiency achieved under these conditions was 80%. The UF4 powders possessed spherical morphology, with diameters between 20 and 80 ㎛. Compared to the SnCl2 precipitation, this process did not allow preferential growth of the precipitates. This improved the compaction of the UF4 - Mg powders mixtures, with densities between 3.0 and 3.5 g/cm3. The purity of the UF4 products was over 98%.

Keywords

Acknowledgement

The authors would like to thank the Chilean Nuclear Energy Commission (ID: CChEN, for its Spanish abbreviation) for their economic support, during every stage of the project.

References

  1. J. Lisboa, M. Barrera, J. Marin, Fabricacion de blancos anulares para Mo-99 utilizando laminas de uranio natural, uranio LEU, Niquel y aluminio estructural Al-3003, in: Iberomet XI, X CONAMET/SAM, Vina del mar, Chile, 2010.
  2. J. Lisboa, J. Marin, M. Barrera, I. Escobar, D. Mena, Recubrimiento de laminas de uranio mediante electrodeposicion de Ni para uso en la produccion de Mo de fision, in: 11° Congreso Binacional de Metalurgia y Materiales, SAM/CONAMET, Rosario, Argentina, 2011.
  3. International Atomic Energy Agency, Nuclear Fuel Cycle Information System, 2009. Vienna, Austria.
  4. K. Huff, Introduction to nuclear power economics, in: Economics of Advanced Reactors and Fuel Cycles, Elsevier Inc., Urbana, IL, United States, 2019, pp. 1-20.
  5. S. Gupta, R. Kumar, S. Satpati, M. Sahu, Effect of oxygen containing compounds in uranium tetrafluoride on its non-adiabatic calciothermic reduction characteristics, Nucl. Eng. Technol. 53 (2021) 1931-1938. https://doi.org/10.1016/j.net.2020.12.021
  6. S. Danielle, Anodic stripping, in: VOLTAMMETRY/Anodic Stripping, Elsevier, Ltd, 2005, pp. 5422-5425.
  7. W. Hansen, Preparation of binary compounds of uranium and thorium, 13 Sept 1966. USA Patent US3272601.
  8. N. Brandon, P. Francis, J. Jeffrey, G. Kelsall, Q. Yin, Thermodynamics and electrochemical behavior of Hg-S-Cl-H2O systems, J. Electroanal. Chem. 497 (2001) 18-32. https://doi.org/10.1016/S0022-0728(00)00445-9
  9. Y. Lee, C. Hu, Mercury drop electrodes, in: Encyclopedia of Applied Electrochemistry, Springer Science Business, New York, 2014, pp. 1233-1239.
  10. Y. Mikkelsen, K. Schroder, Amalgam electrodes for electroanalysis, Electroanalysis 15 (8) (2003) 679-687. https://doi.org/10.1002/elan.200390085
  11. S. Abbas, S. Kim, H. Saleem, S. Ahn, K. Jung, Preparation of metal amalgam electrodes and their selective electrocatalytic CO2 reduction for formate production, Catalysts 9 (367) (2019) 1-13.
  12. P. Rojas, H. Contreras, A. Garrao, F. Valdes, Obtaining metallic uranium from UF6, in: International Meeting on Reduced Enrichment of Research and Test Reactors - RERTR, Santiago, Chile, 2011.
  13. "Fuel Fabrication," United States Nuclear Regulatory Commission [Online]. Available: https://www.nrc.gov/materials/fuel-cycle-fac/fuel-fab.html. (Accessed 20 December 2020).
  14. P. Kawamura, D. Mackay, The evaporation of volatile liquids, J. Hazard Mater. 15 (1987) 343-364. https://doi.org/10.1016/0304-3894(87)85034-3
  15. W. Zhen, L. Jing, Y. Yingju, L. Feng, D. Junyan, Heterogeneous reaction mechanism of elemental mercury oxidation by oxygen species over MnO2 catalyst, Proc. Combust. Inst. 37 (3) (2019) 2967-2975. https://doi.org/10.1016/j.proci.2018.06.132
  16. Y. Liu, X. Xu, M. Sadd, O. Kapitanova, V. Krivchenko, J. Ban, J. Wang, X. Jiao, Z. Song, J. Song, S. Xiong, A. Matic, Insight into the critical role of exchange current density on electrodeposition behavior of lithium metal, Adv. Sci. 8 (5) (2021) 1-11.
  17. A. Milchev, Electrochemical phase formation on a foreign substrate-basic theoretical concepts and some experimental results, Contemp. Phys. 32 (5) (1991) 321-332. https://doi.org/10.1080/00107519108223705
  18. S. Rej, M. Bisetto, A. Naldoni, P. Fornasiero, Well-defined Cu2O photocatalysts for solar fuels and chemicals, J. Mater. Chem. 9 (2021) 5915-5951. https://doi.org/10.1039/D0TA10181H
  19. A. Barnard, Modeling polydispersive ensembles of diamond nanoparticles, Nanotechnology 24 (2013) 1-14. https://doi.org/10.1088/0957-4484/24/8/085703
  20. P. Geysermans, F. Finocchi, J. Goniakowski, R. Hacquart, J. Jupille, Combination of (100), (110) and (111) facets in MgO crystals shapes from dry to wet environment, Phys. Chem. Chem. Phys. 11 (2009) 2228-2233. https://doi.org/10.1039/b812376d