Nuclear Engineering and Technology

Korean Nuclear Society (한국원자력학회)
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Densification of matrix graphite for spherical fuel elements used in molten salt reactor via addition of green pitch coke

  • He, Zhao (Key Laboratory of Carbon Materials, Institute of Coal Chemistry, Chinese Academy of Sciences) ;
  • Zhao, Hongchao (Key Laboratory of Carbon Materials, Institute of Coal Chemistry, Chinese Academy of Sciences) ;
  • Song, Jinliang (Shanghai Institute of Applied Physics, Chinese Academy of Sciences) ;
  • Guo, Xiaohui (Key Laboratory of Carbon Materials, Institute of Coal Chemistry, Chinese Academy of Sciences) ;
  • Liu, Zhanjun (Key Laboratory of Carbon Materials, Institute of Coal Chemistry, Chinese Academy of Sciences) ;
  • Zhong, Yajuan (Shanghai Institute of Applied Physics, Chinese Academy of Sciences) ;
  • Marrow, T. James (Department of Materials, University of Oxford)
  • Received : 2020.12.16
  • Accepted : 2021.09.29
  • Published : 2022.04.25
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Abstract

Green pitch coke with an average particle size of 2 mm was adopted as densifier and added to the raw materials of conventional A3-3 matrix graphite (MG) to prepare modified A3-3 matrix graphite (MMG) by the quasi-isostatic molding method. The structure, mechanical and thermal properties were assessed. Compared with MG, MMG had a more compact structure, and exhibited improved properties of higher mechanical strength, higher thermal conductivity and better molten salt barrier performance. Notably, under the same infiltration pressure of 5 atm, the fluoride salt occupation of MMG was only 0.26 wt%, whereas it was 15.82 wt% for MG. The densification effect of green pitch coke endowed MMG with improved properties for potential use in the spherical fuel elements of molten salt reactor.

Keywords

Acknowledgement

Great thanks to the National Natural Science Foundation of China (No. 91860116 and 52072397) for its financial support for this work. This manuscript is written whilst Zhao He is an Academic Visitor at University of Oxford with the financial support of China Scholarship Council (File No. 201904910864).

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