The release of tritium from irradiated oxide powders was studied by the method of post-irradiation annealing. At 400 to 660C, the release was a diffusion-controlled process. The diffusion coefficient of T in the two powders used was given by:

UOX:     D(cm2/s) = 6.6 x 10-13 exp[-24.5(kcal/mol)/RT]

MINOX:     D(cm2/s) = 7.6 x 10-13 exp[-24.0(kcal/mol)/RT]

A.R.Palmer, D.Roman, H.J.Whitfield: Journal of Nuclear Materials, 1964, 14, 141-6