The effect of Cu (0–60wt%) upon the H permeation of Pd–Cu coated V–15Ni composite membranes was investigated at 423 to 673K. The H permeability of composite membrane was closely related to the over-layer composition, it increased with the Cu content until 40wt%Cu, and then decreased rapidly with Cu content increasing. The highest H permeability was obtained for the Pd60Cu40/V–15Ni composite membrane. At 473 to 673K, the H permeability of Pd60Cu40/V–15Ni composite membrane was some 1.5 to 5.0 times that of Pd60Cu40 alloy membrane. Hydrogen permeation kinetics of the Pd–Cu/V–15Ni composite membranes were limited mainly by bulk diffusion at above 473K. At below 473K, the H permeation flux saturates at high upstream H2 pressure, surface-related reaction should be responsible for the flux saturation at low temperature.

Effect of Overlayer Composition on Hydrogen Permeation of Pd–Cu Alloy Coated V–15Ni Composite Membrane. J.Y.Yang, C.Nishimura, M.Komaki: Journal of Membrane Science, 2006, 282[1-2], 337-41