Skip to main content
Log in

Anodic Processes of Uranium Alloys Containing Palladium and Neodymium in 3LiCl–2KCl–UCl3 Melts

  • Published:
Russian Metallurgy (Metally) Aims and scope


A combined technological scheme for the reprocessing of a mixed nitride uranium–plutonium spent fuel, which consists of pyrochemical operations and hydrometallurgical refining of uranium, plutonium, and neptunium, is currently being developed at the reprocessing unit of the pilot demonstration power complex of the Siberian Chemical Plant. According to this scheme, the target pyrochemical reprocessing products (the actinide content not lower than 99.9%) purified from the main mass of fission products are directed to hydrometallurgical reprocessing. Pyrochemical reprocessing requires a technology of electrorefining of the metallized spent nuclear fuel. To carry out electrorefining, it is necessary to determine processes and conditions of anodic dissolution of the alloys simulating the product of primary “metallization” operation. The results of studying the anodic dissolution of model U–Pd and U–Pd–Nd alloys with different concentrations of palladium and neodymium in the melts based on 3LiCl–2KCl–UCl3 (10.1 wt % UCl3) at 550°C using different methods are presented. The uranium alloys containing palladium and neodymium are prepared by direct melting of metallic uranium, PdAP-1 metallic palladium powder, and metallic neodymium (99.99%) in a high-purity argon medium (99.998%). Electrochemical measurements are carried out on an Autolab 302N potentiostat/galvanostat equipped with a Booster 20A high-current device. The anodic polarization curves consist of only one oxidation wave attributed to the dissolution of uranium metal. An increasing in the palladium content in the alloy from 1.5 to 10.0 wt % does not affect the shape of the polarization curves. An increase in the neodymium content in the alloy from 1.0 to 10.0 wt % does not either influence on the shape of the polarization curves. The parameters of electrorefining of uranium alloys containing palladium and neodymium are determined. The limiting current density of uranium dissolution from the uranium alloys containing palladium and neodymium in the 3LiCl–2KCl–UCl3 (10.1 wt % UCl3) electrolyte at 550°C is 0.4 A/cm2. Palladium does not transfer into the melt due to anodic dissolution, and neodymium is accumulated in the electrolyte only for refining the alloy with 10.0 wt % neodymium, which is much higher than the possible real concentrations of components of the electrorefined uranium alloy in the technological flowsheet of processing the spent nuclear fuel.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1.
Fig. 2.
Fig. 3.
Fig. 4.
Fig. 5.
Fig. 6.
Fig. 7.
Fig. 8.
Fig. 9.


  1. S. Imoto, “Chemical state of fission products in irradiated UO2,” J. Nucl. Mater. 140 (1), 19–27 (1986).

    Article  CAS  Google Scholar 

  2. R. P. Bush, “Recovery of platinum group metals from high level radioactive waste. Possibilities of separation and use re-evaluated,” Platinum Met. Rev. 35 (4), 202–208 (1991).

    CAS  Google Scholar 

  3. D. Yu. Lyubimov, I. A. Deryabin, G. S. Bulatov, and K. N. Gedgovd, “Thermodynamic modeling of the phase composition of mixed uranium–plutonium mononitride with an oxygen impurity under 140 GW day t–1 irradiation to ignition at 900–1400 K,” Atom. Energ. 118 (1), 24–19 (2015).

    Article  Google Scholar 

  4. G. S. Bulatov, K. N. Gedgovd, and D. Yu. Lyubimov, “Thermodynamic analysis of chemical and phase compositions of uranium–plutonium nitride irradiated with fast neutrons depending on temperature and ignition,” Materialoved. 1, 2–7 (2009).

    Google Scholar 

  5. H. Kleykamp, “The chemical state of the fission products in oxide fuels,” J. Nucl. Mater. 131 (2–3), 221–246 (1985).

  6. S. C. Middlemas, M. M. Craig, C. A. Adkins, F. D. Lemma, K. R. Tolman, M. T. Benson, and C. J. Hin, “Effects of intermetallic compounds on the thermophysical properties of uranium–palladium alloys,” Alloys Compd., (2021).

    Book  Google Scholar 

  7. R. Prasad, S. Dash, S. C. Parida, Z. Singh, and V. J. Venugopal, “Gibbs energy of formation of UPd3(s),” J. Nucl. Mater. 277 (1), 45–48 (2000).

    Article  CAS  Google Scholar 

  8. H. Kleykamp, “Highlights of experimental thermodynamics in the field of nuclear fuel development,” J. Nucl. Mater. 344 (1–3), 1–7 (2005).

  9. E. H. P. Cordfunke, R. P. Muis, G. Wijbenga, R. Burriel, H. Zainel, M. To, E. F. Westrum, Jr., “Thermodynamics of uranium intermetallic compounds. I. Heat capacity of UPd3 from 5 to 850 K,” J. Chem. Thermodyn. 20, 815–823 (1988).

    Article  Google Scholar 

  10. V. A. Kesikopulos, A. M. Potapov, A. E. Dedyukhin, and Yu. P. Zaikov, “Production of UPd3 intermetallic compound and study of its thermodynamic characteristics,” in Proceedings of Workshop on Electrochemistry in Distributed and Nuclear Power Generation (Azhur, Nalchik, 2022), pp. 224–226.

  11. K. E. Strepetov, A. A. Osipenko, and V. A. Volkovich, “Electrochemical behavior of uranium–palladium alloys in molten eutectic mixture of lithium, potassium and cesium chlorides,” AIP Conf. Proc. 2466 (1), 050033 (2022).

    Article  CAS  Google Scholar 

  12. H. Okamoto, “Pd–U (palladium–uranium),” J. Phase Equilibr. 13 (2), 222–223 (1992).

    Article  Google Scholar 

  13. D. G. Parnell, N. H. Brett, H. R. Haines, and P. E. Potter, “Phase relationships in the ternary system U–Nd–Pd,” J. Less Common Met. 118 (1), 141–152 (1986).

    Article  CAS  Google Scholar 

  14. D. A. Zolotarev, D. I. Nikitin, and I. B. Polovov, “Electrode processes in 3LiCl–2KCl–UCl3 melts: Investigation of temperature and uranium concentration influence,” AIP Conf. Proc. 2174 (1), 020276 (2019).

    Article  CAS  Google Scholar 

  15. D. I. Nikitin, I. B. Polovov, A. V. Shchetinskii, A. S. Dedyukhin, V. A. Volkovich, and O. I. Rebrin, “Processes of anodic dissolution of U–Pd alloys in 3LiCl–2KCl–UCl3 melts,” in Proceedings of Workshop on Electrochemistry in Distributed and Nuclear Power Generation (Azhur, Nalchik, 2022), pp. 294–297.

  16. A. L. Hames, A. Paulenova, J. L. Willit, and M. A. Williamson, “Phase equilibria studies of the LiCl–KCl–UCl3 system,” J. Nucl. Technol. 203 (3), 272–281 (2018).

    Article  Google Scholar 

Download references


This work was supported by JSC Proryv.

Author information

Authors and Affiliations


Corresponding author

Correspondence to D. I. Nikitin.

Ethics declarations

The authors of this work declare that they have no conflicts of interest.

Additional information

Translated by E. Yablonskaya

Publisher’s Note.

Pleiades Publishing remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Nikitin, D.I., Polovov, I.B., Rebrin, O.I. et al. Anodic Processes of Uranium Alloys Containing Palladium and Neodymium in 3LiCl–2KCl–UCl3 Melts. Russ. Metall. 2023, 970–976 (2023).

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: