Inorganic membrane supports, for hydrogen separation, must provide adequate surface morphology for the deposition of thin film membranes while offering acceptable permeability and mechanical strength. Supports prepared from stabilized suspensions of Sumitomo AKP30 and AKP15 powder were shown to exhibit ideal surface morphology (average roughness similar to 30nm) and excellent mechanical strength (> 200MPa), but inadequate permeability, similar to 1 x 10(-6) mol/m(2) sPa for H-2 at STP. The colloidal stabilization, subsequent vacuum filtration and sintering of coarse similar to 3 mu m phi alpha-Al2O3 particles are shown to increase pore size from similar to 70nm (AKP30) to similar to 700nm (AA3) and consequently improve permeability by similar to 10x. The cost price of these supports can be decreased and sufficient flexural strength achieved with a low temperature phosphate bonding technique. Through the precise control of the colloidal chemistry and consolidation process, the near surface morphology of the supports can be intrinsically graded with similar to 0.5 mu m. particles gradually coarsening to similar to 3 mu m. Supports generated in this manner then exhibit a smooth surface morphology comparable to AKP15 supports (average roughness similar to 100 nm) and mechanical strengths of similar to 100MPa. (c) 2007 Published by Elsevier Ltd. on behalf of International Association for Hydrogen Energy.