Tritium release from ceramic breeder materials deposited with noble metals

Lithium orthosilicate and lithium aluminate are the candidates of the breeder material of the tritium-breeding blanket. To enhance the rate of tritium release from these breeder materials, 0.2 wt.% of palladium was impregnated into the breeder materials by the incipient wet impregnation method. The lithium orthosilicate and the lithium aluminate pebbles with or without Pd were irradiated in the Kyoto university research reactor, and out-of-pile annealing experiments were performed. When the breeder materials were deposited with a catalytic additive, such as Pd the ratio of the tritium discharged in the molecular form of tritium (HT) increased. It was also found that the amount of the tritium discharged from the lithium orthosilicate pebbles with a catalytic additive at the low temperatures is greater compared with lithium aluminate.