Surface inventory of tritium on Li2TiO3

Though lithium ceramic materials such as Li2O, LiAlO2, Li2ZrO3, Li4SiO4 and Li2TiO3 are considered as breeding materials in the blanket of a D-T fusio n reactor, the release behavior of the bred tritium in these solid breeder materials has not been fully understood, yet. It has been pointed out by th e present authors that it is essential to understand such mass transfer ste ps as diffusion of tritium in the grain of breeder material, absorption of water vapor into bulk of the grain, and adsorption of water on surface of t he grain, together with two types of isotope exchange reactions for estimat ion of the tritium inventory in a uniform solid breeder blanket under the s teady-state condition. The adsorption capacity and the isotope exchange cap acity on the Li2TiO3 surface are experimentally obtained in this study. Com parison of the tritium inventory estimated for the Li2TiO3 blanket with the inventory for LiAlO2, Li2ZrO3 or Li4SiO4 blanket using the model presented by the present authors shows that the Li2TiO3 blanket gives the smallest t ritium inventory among the candidate ceramic breeding materials. (C) 2001 E lsevier Science B.V. All rights reserved.