Nuclear Engineering and Technology

Korean Nuclear Society (한국원자력학회)
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Effect of process parameters on the recovery of thorium tetrafluoride prepared by hydrofluorination of thorium oxide, and their optimization

  • Kumar, Raj (Uranium Extraction Division, Bhabha Atomic Research Centre) ;
  • Gupta, Sonal (Uranium Extraction Division, Bhabha Atomic Research Centre) ;
  • Wajhal, Sourabh (Solid State Physics Division, Bhabha Atomic Research Centre) ;
  • Satpati, S.K. (Uranium Extraction Division, Bhabha Atomic Research Centre) ;
  • Sahu, M.L. (Uranium Extraction Division, Bhabha Atomic Research Centre)
  • Received : 2021.03.23
  • Accepted : 2021.11.04
  • Published : 2022.05.25
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Abstract

Liquid fueled molten salt reactors (MSRs) have seen renewed interest because of their inherent safety features, higher thermal efficiency and potential for efficient thorium utilisation for power generation. Thorium fluoride is one of the salts used in liquid fueled MSRs employing Th-U cycle. In the present study, ThF4 was prepared by hydro-fluorination of ThO2 using anhydrous HF gas. Process parameters viz. bed depth, hydrofluorination time and hydrofluorination temperature, were optimized for the preparation of ThF4 in a static bed reactor setup. The products were characterized with X-Ray diffraction and experimental conditions for complete conversion to ThF4 were established which also corroborated with the yield values. Hydrofluorination of ThO2 at 450 ℃ for half an hour at a bed depth of 6 mm gave the best result, with a yield of about 99.36% ThF4. No unconverted oxide or any other impurity was observed. Rietveld refinement was performed on the XRD data of this ThF4, and Chi2 value of 3.54 indicated good agreement between observed and calculated profiles.

Keywords

Acknowledgement

The authors are thankful to Shri Pramendra Singh, Shri U.B. Naik, Shri Dulal Mandal and all other staff of our lab for their extended support in carrying out the hydrofluorination experiments. The authors also thank Smt. Karuna Kamble for their support in carrying out XRD experiments and analysis. The authors thank Shri K.N. Hareendhran and Shri S.V. Kadam for carrying out particle size analysis.

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