This paper reports on the experimental investigation of tritium permeation in flibe

(2LiF–BeF2). A stainless steel cell formed by two independent volumes separated

by a 2mm-thick nickel membrane was maintained at between 500 and 700C. A

controlled amount of T2 gas was flowed in an excess of argon in the source volume

in contact with the underside of the nickel membrane, while a layer of molten salt

was in contact with the upper side. The tritium permeating above the liquid surface

was carried by an argon flow to a diagnostic system comprised of a quadrupole

mass spectrometer, a gas chromatographer and a proportional counter. Tritium

permeability in flibe as a function of temperature was determined by the measured

permeation flow rates reached in steady-state conditions, while the diffusivity was

determined by fitting the transient process with the analytical solution for the

diffusion process. As a result, the solubility of tritium in flibe as a function of

temperature was also determined.

Measurement of Tritium Permeation in Flibe (2LiF–BeF2). P.Calderoni, P.Sharpe,

M.Hara, Y.Oya: Fusion Engineering and Design, 2008, 83[7-9], 1331-4