Tritium release kinetics of lithium silicates with irradiation defects

Tritium release kinetics of lithium ortho- and metasilicates with irradiation defects was studied by out-of-pile experiments. Tritium was released mainly as HTO, but the HT yield increased with the increasing partial pressure of H2 in the sweep gas. Some dependence of the HT yield on neutron fluence was observed. Tritium release kinetics of HTO and HT were well interpreted by taking a combined regime of diffusion and first-order reaction. The dependence of the diffusion constant and reaction rate constant on neutron fluence was determined. In the studied range, the effects of neutron fluence were observed more clearly for Li2SiO3 than for Li4SiO4.