Solubility of hydrogen isotopes in palladium

An all-metal facility has been built to handle about 1000 Ci of tritium for studies of the tritium behavior in metals. First measurements of the pressure-composition-temperature relationship for the palladium-tritium system $\mathrm{Pd}{\mathrm{T}}_x$ are reported for the pressure range $0.1\le p\le 2$ bar, the composition range $0.02\le x\le 0.65$, and the temperature range $35\le T\le 125°$C together with the results of the PdH and PdD systems measured under the same experimental conditions. The main conclusions are that the inequality $p_{{\mathrm{T}}_2}>p_{{\mathrm{D}}_2}>p_{{\mathrm{H}}_2}$ holds at equal concentrations and temperatures and that the $\beta \to \alpha$ transition enthalpies show a strong isotopic effect, whereas the entropies do not.