Evaluation of tritium release behavior from Li2TiO3 during DT neutron irradiation by use of an improved tritium collection method

• Published in: Fusion engineering and design Vol. 112; pp. 480 - 485
• Main Authors: Edao, Yuki, Kawamura, Yoshinori, Hoshino, Tsuyoshi, Ochiai, Kentaro
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.11.2016
• Subjects: Li2TiO3; Neutron irradiation; Sweep gas; Tritium breeder; Tritium collection method; Tritium release behavior; Li2TiO3; Sweep gas; Neutron irradiation; Tritium collection method; Tritium release behavior; Tritium breeder
• ISSN: 0920-3796; 1873-7196
• DOI: 10.1016/j.fusengdes.2016.06.013

•Behavior of tritium released from Li2TiO3 under neutron irradiation was measured.•Tritium collection method with hydrophobic catalyst was demonstrated successfully.•Temperature of Li2TiO3 was dominant to control the chemical form of tritium release. The accurate measurement of behavior of bred tritium released from a tritium breeder is indispensable to understand the behavior for a design of a tritium extraction system. The tritium collection method combined a CuO bed and water bubbles was not suitable to measure transient behavior of tritium released from Li2TiO3 during neutron irradiation because tritium released behavior was changed to be delayed due to adsorption of oxidized tritium on the CuO. Hence, the tritium collection method with hydrophobic catalyst instead of the CuO was demonstrated and succeeded the accurate release measurement of tritium from Li2TiO3. With the method, we assessed the behavior of tritium release under the various conditions since tritium should be released from Li2TiO3 as the form of HT as much as possible from the view point of the fuel cycle. Our results indicated; promotion of isotopic exchange reaction on the surface of Li2TiO3 by addition of hydrogen in sweep gas is mandatory in order to release tritium smoothly from Li2TiO3 irradiated with neutrons; the favorable sweep gas to release as the form of HT was hydrogen added inert gas; and the temperature of Li2TiO3 was the dominant parameter to control the chemical form of tritium released from the Li2TiO3.