The oxidation of UF4 in FLiNaK melt and its electrolysis

  • Dong Han
  • Changfeng She
  • Yongsheng Niu
  • Xu Yang
  • Junxia Geng
  • Rongrong Cui
  • Lixin Sun
  • Congwei Hu
  • Yiyang Liu
  • Tao Su
  • Hongtao Liu
  • Wei HuangEmail author
  • Yu Gong
  • Qingnuan LiEmail author


The oxidation of UF4 in LiF–NaF–KF (FLiNaK) melt with oxygen sparging was conducted at 823 K and analyzed by in situ infrared spectrometer, UV–Vis absorption spectrometer, and other characterizations with thermodynamic calculations, indicating UF4 was converted to UO2F2 with the following reaction mechanism: 2UF4 (l) + O2(g) + 2H2O(g) = 2UO2F2(l) + 4HF(g). Cyclic voltammetry measurements showed that the reduction of UO22+ in oxidized melt exhibited two steps both with one exchanged electron: UO22+ + e → UO2+ and UO2+ + e → UO2. By potentiostatic electrolysis, the product of UO2 was obtained with nanoscale triangular sheet structure.


UF4 FLiNaK Oxidation O2 sparging UO22+ Potentiostatic electrolysis 



This work was supported by the “Strategic Priority Research Program” and “Frontier Science Key Program” of the Chinese Academy of Sciences (Grant No. XDA02030000 and QYZDYSSW-JSC016), National Natural Science Foundation of China (21601200) and Youth Innovation Promotion Association of CAS (2017307).


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2019

Authors and Affiliations

  1. 1.Shanghai Institute of Applied PhysicsChinese Academy of SciencesShanghaiChina
  2. 2.University of Chinese Academy of SciencesBeijingChina
  3. 3.Center of Excellence TMSR Energy SystemChinese Academy of SciencesShanghaiChina

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