Plasma and Fusion Research

Volume 13, 3404071 (2018)

Regular Articles

Control of Chemical Forms of Tritium in FLiNaK under Low Flux Neutron Irradiation
Kohki KUMAGAI1), Teruya TANAKA1,2), Juro YAGI1,2), Takashi WATANABE2), Fuminobu SATO3), Shingo TAMAKI3), Isao MURATA3) and Akio SAGARA1,2)
SOKENDAI (The Graduate University for Advanced Studies), Toki 509-5292, Japan
National Institute for Fusion Science, Toki 509-5292, Japan
Graduate School of Engineering, Osaka University, Suita 565-0871, Japan
(Received 28 December 2017 / Accepted 11 April 2018 / Published 25 June 2018)


The use of the isotopic exchange between tritium produced in molten salts and hydrogen molecules in a sweep gas has been proposed as a way of recovering tritium in a self-cooled molten salt liquid blanket system [1-3]. In the present study, rate coefficients of the isotopic exchange for molten FLiNaK (LiF-NaF-KF) have been evaluated in a series of low flux neutron irradiation experiments with an AmBe neutron source at the OKTAVIAN facility of Osaka University in Japan. Approximately 300 cm3 of FLiNaK were irradiated at 773 K in an Inconel 600 crucible, and tritium released from the free surface of FLiNaK has been swept by a pure He gas or He+H2 (0.1%) gas. The change in the amounts of soluble tritium (TF, HTO) and insoluble tritium (HT) recovered by water bubblers has been evaluated in each sweep gas to evaluate the effectiveness of the tritium recovery with the isotopic exchange.


FLiNaK, molten salt, AmBe neutron source, low flux neutron, tritium recovery, isotopic exchange

DOI: 10.1585/pfr.13.3404071


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