Experimental investigation of tritium release behavior from neutron irradiated LiAlO2 with Zr for tritium production in a high-temperature gas-cooled reactor

• Most of the adsorbed water on LiAlO 2 was released over around 250 °C. • Most of T was released as tritiated water vapor from the irradiated LiAlO 2 powder. • T release peaks from the irradiated LiAlO 2 were observed at 250, 550, 700, 800 °C. • T was mostly released as gaseous tritium from the preheated LiAlO 2 mixed with zr. • T release peak from the preheated LiAlO 2 mixed with Zr was observed at 600 °C. Tritium production using nuclear reactions of neutrons with lithium in a high temperature gas-cooled reactors has been studied as an external source of fuel tritium in the early stage of fusion reactor operation. In order to control tritium migration throughout the reactor, it is important to understand tritium release behaviors from Zr-containing LiAlO 2 , which are used as tritium producing materials. In this study, tritium release behavior from neutron irradiated LiAlO 2 with and without Zr ware investigated by heating to 900 °C. In the case of heating only LiAlO 2 , most tritium was released in the chemical form of HTO. On the other hand, in the case of heating Zr-containing LiAlO 2 , the chemical form of tritium was mostly HT. This result indicates that even if tritium is released from LiAlO 2 as HTO, it is effectively absorbed by Zr at 900 °C.