Among the various tritium transport processes in lithium ceramics, the impo
rtance and the detailed mechanism of surface reactions remain to be elucida
ted. The dynamic adsorption and desorption model for tritium desorption fro
m lithium ceramics, especially Li2O was constructed. From the experimental
results, it was considered that both H-2 and H2O are dissociatively adsorbe
d on Li2O and generate OH- on the surface. In the first model developed in
1994, it was assumed that either the dissociative adsorption of H-2 or H2O
on Li2O generates two OH- on the surface. However, recent calculation resul
ts show that the generation of one OH- and one H- is more stable than that
of two OH- s by the dissociative adsorption of H-2 Therefore, assumption of
H-2 adsorption and desorption in the first model is improved and the triti
um release behavior from Li2O surface is evaluated again by using the impro
ved model. The tritium residence time on the Li2O surface is calculated usi
ng the improved model, and the results are compared with the experimental r
esults. The calculation results using the improved model agree well with th
e experimental results than those using the first model. (C) 2000 Elsevier
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