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A preliminary study of pilot-scale electrolytic reduction of UO2 using a graphite anode

  • Kim, Sung-Wook (Pyroprocessing Division, Korea Atomic Energy Research Institute) ;
  • Heo, Dong Hyun (Pyroprocessing Division, Korea Atomic Energy Research Institute) ;
  • Lee, Sang Kwon (Pyroprocessing Division, Korea Atomic Energy Research Institute) ;
  • Jeon, Min Ku (Pyroprocessing Division, Korea Atomic Energy Research Institute) ;
  • Park, Wooshin (Pyroprocessing Division, Korea Atomic Energy Research Institute) ;
  • Hur, Jin-Mok (Pyroprocessing Division, Korea Atomic Energy Research Institute) ;
  • Hong, Sun-Seok (Pyroprocessing Division, Korea Atomic Energy Research Institute) ;
  • Oh, Seung-Chul (Pyroprocessing Division, Korea Atomic Energy Research Institute) ;
  • Choi, Eun-Young (Pyroprocessing Division, Korea Atomic Energy Research Institute)
  • Received : 2017.03.06
  • Accepted : 2017.05.23
  • Published : 2017.10.25

Abstract

Finding technical issues associated with equipment scale-up is an important subject for the investigation of pyroprocessing. In this respect, electrolytic reduction of 1 kg $UO_2$, a unit process of pyroprocessing, was conducted using graphite as an anode material to figure out the scale-up issues of the C anode-based system at pilot scale. The graphite anode can transfer a current that is 6-7 times higher than that of a conventional Pt anode with the same reactor, showing the superiority of the graphite anode. $UO_2$ pellets were turned into metallic U during the reaction. However, several problems were discovered after the experiments, such as reaction instability by reduced effective anode area (induced by the existence of $Cl_2$ around anode and anode consumption), relatively low metal conversion rate, and corrosion of the reactor. These issues should be overcome for the scale-up of the electrolytic reducer using the C anode.

Acknowledgement

Supported by : National Research Foundation of Korea (NRF)

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