PUBLICATION: RADIOCHIMICA ACTA

AUTHORS: Cheng, ZQ; Wang, XH; Zhao, ZQ; Geng, JX; Hu, JF; Chen, JG; Cai, XZ; Li, WX; Dou, Q; Li, QN

 

The (UF4)-U-235,238 was irradiated by photo-neutrons, distribution and behavior of the fission product Nb-95 from irradiated (UF4)-U-235,238 in FLiBe salt were investigated by the measurement of its activity in the salt with the gamma-ray spectroscopy. The experiments indicated that a part of Nb-95 deposited on the surfaces of graphite and Hastelloy, as the moderator and the structural materials of molten salt reactor (MSR), respectively, and the majority of Nb-95 maintained in molten salt. Addition of lithium metal made Nb-95 in salt to be reduced and settled, leading to the decrease in its activity. Degree of the decrease was found to be correlated with niobium concentration. The experimental results supported the statement proposed early by ORNL, that Nb-95 might be used as a redox indicator for MSR. Finally, the problem met with on-site monitoring for redox potential in MSR was pointed, and a possible protocol to resolve the problem was proposed.

 

LINKS: http://dx.doi.org/10.1515/ract-2020-0057