Electrochemical preparation and spectroelectrochemical study of neptunium chloride complexes in LiCl–KCl eutectic melts

  • Dae-Hyeon Kim
  • Tae-Hong ParkEmail author
  • Sang-Eun Bae
  • Nari Lee
  • Jong-Yun Kim
  • Young-Hwan Cho
  • Jei-Won Yeon
  • Kyuseok Song


We prepared neptunium chloride complexes electrochemically and performed spectroelectrochemical measurements of neptunium ions in LiCl–KCl eutectic melts at 450 °C, where the neptunium concentrations studied were in the range of 0.1–1 mM. We observed a highly absorbing fd transition band of Np3+ at 383 nm, which was used to determine an formal potential of the Np4+|Np3+ redox couple (E° = 0.45 V vs. Ag|Ag+) with a solution of concentration as low as ~0.1 mM. This result agreed well with the value (E° = 0.42 V vs. Ag|Ag+) determined by cyclic voltammetry with a ~15 mM solution.


Neptunium Molten salt Transuranium Pyroprocess Spectroelectrochemical technique 



This work was supported by a National Research Foundation of Korea (NRF) Grant, funded by the Korean government (MSIP) (No. 2012M2A8A5025923).


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2015

Authors and Affiliations

  • Dae-Hyeon Kim
    • 1
    • 2
  • Tae-Hong Park
    • 1
    Email author
  • Sang-Eun Bae
    • 1
    • 3
  • Nari Lee
    • 1
    • 4
  • Jong-Yun Kim
    • 1
    • 3
  • Young-Hwan Cho
    • 1
  • Jei-Won Yeon
    • 1
    • 3
  • Kyuseok Song
    • 1
  1. 1.Nuclear Chemistry Research DivisionKorea Atomic Energy Research InstituteDaejeonRepublic of Korea
  2. 2.Department of ChemistryKorea UniversitySeoulRepublic of Korea
  3. 3.University of Science and Technology DaejeonRepublic of Korea
  4. 4.Department of ChemistryChungbuk National UnviersityCheongjuRepublic of Korea

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