Redox equilibrium of u4+/u3+ in molten nacl-2cscl by uv-vis spectrophotometry and cyclic voltammetry

Takayuki Nagai, Akihiro Uehara, Toshiyuki Fujii, Osamu Shirai, Nobuaki Sato, Hajimu Yamana

Research output: Contribution to journalArticlepeer-review

3 Citations (Scopus)


In order to investigate the redox equilibrium of uranium ions in molten NaCL-2CsCL, UV-Vis absorption spectrophotometry measurements were performed for U4+ and U3+ in molten NaCL-2CsCL at 923 K under simultaneous electrolytic control of their ratio. Prominent absorption bands at 480 and 570 nm were assigned to U3+, and their molar absorptivities were determined to be 1,260±42 and 963±32 mol−−1 respectively. From the dependence of the rest potential of the melt on the spectrophotometrically determined ratio of [U4+]/[U3+], the standard redox potential of the couple U4+/U3+ at 923K was determined to be −1.481±0.004 V vs. Cl2/Cl. Cyclic voltammetry measurements were carried out for the couple U4+/U3+, and the results agreed well with this standard redox potential value. By the results of cyclic voltammetry, a temperature dependence of the standard redox potential was found to be −2.094+6.639×10−4 T (T=823-923 K).

Original languageEnglish
Pages (from-to)1025-1031
Number of pages7
Journaljournal of nuclear science and technology
Issue number12
Publication statusPublished - 2005 Dec


  • Absorption spectrophotometry
  • Cesium chloride
  • Cyclic voltammetry
  • Dry reprocessing
  • Electro-winning method
  • Molar absorptivity
  • Molten salt
  • Redox potential
  • Sodium chloride
  • Uranium ion

ASJC Scopus subject areas

  • Nuclear and High Energy Physics
  • Nuclear Energy and Engineering


Dive into the research topics of 'Redox equilibrium of u4+/u3+ in molten nacl-2cscl by uv-vis spectrophotometry and cyclic voltammetry'. Together they form a unique fingerprint.

Cite this