Distribution and behaviour of 233Pa in 2LiF-BeF2 molten salt

Zhongqi Zhao; Jifeng Hu; Zhiqiang Cheng; Junxia Geng; Wenxin Li; Qiang Dou; Jingen Chen; Qingnuan Li; Xiangzhou Cai

doi:10.1039/d0ra09572a

Distribution and behaviour of ²³³Pa in 2LiF-BeF₂ molten salt

RSC Adv. 2021 Feb 15;11(13):7436-7441. doi: 10.1039/d0ra09572a. eCollection 2021 Feb 10.

Authors

Zhongqi Zhao^{1

2

3}, Jifeng Hu^{1

2

3}, Zhiqiang Cheng^{1

2

3}, Junxia Geng^{1

2

3}, Wenxin Li^{1

2}, Qiang Dou^{1

2}, Jingen Chen^{1

2}, Qingnuan Li^{1

2}, Xiangzhou Cai^{1

2}

Affiliations

¹ Shanghai Institute of Applied Physics, Chinese Academy of Sciences Shanghai 201800 China.
² Centre of Excellence TMSR Energy System, Chinese Academy of Sciences Shanghai 201800 China.
³ University of Chinese Academy of Sciences Beijing 100049 China.

Abstract

Distribution and behavior of ²³³Pa, essential in the thorium-uranium nuclear fuel cycle, were studied in 2LiF-BeF₂ (66 : 34 mole%, FLiBe) molten salt by γ-ray spectrometry. The experiments showed that ²³³Pa deposited slightly on the surface of graphite crucible. The addition of Hastelloy and metallic lithium decreased the ²³³Pa specific activity in the salt by 1 to 2 orders of magnitude rapidly. Analysis indicated that reductive deposition of ²³³Pa was responsible for the rapid decrease of ²³³Pa specific activity in the salt. Additional experiments strongly supported the mechanism of reductive deposition of ²³³Pa induced by Hastelloy and metallic lithium. In view of the large deposition of ²³³Pa on Hastelloy, the possible influence of fissile nuclide ²³³U produced from ²³³Pa decay on the operation of thorium-based molten salt reactor was discussed.