Preparation of supported palladium membrane and separation of hydrogen

Palladium acetate was sublimed at a reduced pressure at 400 degrees C, carried into the macropores of the porous wall of an alpha-alumina support tube and was decomposed there. A thin palladium membrane which was thus formed showed a hydrogen permeance of 10(6)mol . m(2) . s(1) . Pa-1 and a hydrogen/nitrogen permselectivity higher than 1000. The membrane was stable against hydrogen embrittlement even when the permeation temperature was varied between 100 and 300 degrees C, and it was stable to sulfur or chlorine, To rest the ability of this system for the separation of hydrogen and deuterium, a palladium disk was used instead of the prepared membrane since a definite membrane thickness was necessary for calculation, When H-2 and D-2 permeated through the membrane independently, the H/D permselectivity was approximately 7 at 150-200 degrees C under a feed side pressure of 0.4 MPa and a permeate side pressure of 0.1 MPa. When a mixture of H-2 and D-2 was fed, the H/D permselectivity was reduced to 1.2-1.6.