Separation and concentration of hydrogen isotopes by palladium-alloy membrane. (II) Measurement of permeability and solubility through palladium-alloy membrane and tritium separation.

Permeability and solubility of tritium in Pd-alloy membrane were measured in the system of tritium-protium mixture gas, whose isotopic ratio is 〓 10-6. Permeability is proportional to Pu0.62 and solubility is proportional to Pe0.52, where Pu and Pe is upstream pressure and equilibrium pressure, respectively. The true separation factor for the protium-tritium system was obtained by the comparison between the numerical calculation method, which takes into account the effect of diffusion boundary layer, and experimental data. The intrinsic membrane separation factor (permeability ratio of H2 to T2) was estimated as 2.05. The dependence of the separation factor α on the cut θ is calculated, which shows that α becomes larger, when θ becomes larger, and it became clear that α is larger in case of large tritium ratio with same θ.