Release behavior of water vapor and mass loss from lithium titanate

The release behavior of tritium generated by neutron irradiation is strongly affected by the surface water of ceramic breeder materials. In the present study, the release behavior of water vapor from Li2TiO3 with added Li, which is in a developmental stage in JAEA (Japan Atomic Energy Agency) as an advanced tritium breeder materials, was observed at elevated temperatures. The capacity of chemical adsorbed water in nitrogen atmosphere and the water formation capacity in hydrogen atmosphere were quantified, respectively. The mass loss of the Li2TiO3 due to evaporation of Li-containing species at 900 °C in 10,000 ppmH2/N2 was estimated to be 1.8% of initial sample weight. The majority of evaporated Li adhered to a quartz tube around the sample bed. It was shown experimentally that the mass loss in water vapor atmosphere is larger than that in hydrogen atmosphere.