Nuclear Techniques ›› 2018, Vol. 41 ›› Issue (6): 60602-060602.doi: 10.11889/j.0253-3219.2018.hjs.41.060602

• NUCLEAR ENERGY SCIENCE AND ENGINEERING • Previous Articles     Next Articles

Theoretical study of tritium adsorption on graphite in molten salt reactor

WU Xijun1,2, QIAN Nan2, WANG Guanghua2, HUANG Yu2, DENG Ke2, CHEN Xuekun1, ZENG Youshi2, WU Shengwei2, LIU Wenguan2, LIU Wei2   

  1. 1 School of Mathematics and Physics, University of South China, Hengyang 421001, China;
    2 Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Jiading Campus, Shanghai 201800, China
  • Received:2017-11-14 Revised:2018-01-15 Online:2018-06-10 Published:2018-06-06
  • Supported by:
    Supported by National Natural Science Foundation of China (No.51601212), Strategic Priority Research Program of Chinese Academy of Sciences (No.XDA0202020)

Abstract: [Background] In molten salt reactor, the graphite can adsorb a mass of tritium. Fluorine is a constituent of molten salt, and neutron irradiation can induce a number of defects on the graphite in molten salt reactor. It is necessary to study the influence of fluorine and the defects of the graphite on tritium adsorption in molten salt reactor.[Purpose] This study aims to reveal the influence mechanism of fluorine and monovacancy defect on tritium adsorption on graphite surface.[Methods] Simulation study of the adsorption behaviors of hydrogen, fluorine and hydrogen fluoride on the surfaces of perfect graphene and vacancy-defected graphene were carried out by using first-principles calculations.[Results] The results indicate that fluorine preferentially bonds with carbon atoms when hydrogen and fluorine exist at the same time. The monovacancy on graphite surface prompts hydrogen fluoride molecule to dissolve and bond with carbon atom. Moreover, the graphite surface can be distorted after adsorbing hydrogen and fluorine.[Conclusion] Tritium generated from the molten salt reactor will be preferentially adsorbed and accumulate in the regions with more reactive activities such as monovacancy.

Key words: Tritium, Fluorine, Graphite, Adsorption, First-principles calculation, Molten salt reactor

CLC Number: 

  • TL341