Fabrication and characterization of Pd/porous TiAl alloy composite membrane for hydrogen separation

Porous Ti-35%Al Al intermetallic copound was fabricated by the reactive synthesis of mixed titanium and aluminum elemental powders. The porous TiAl alloy materials with the maximum pore size of 2-3μm have been prepared by the optimized procedure. Pure Pd membrane on the porous TiAl alloy composite substrate was obtained by electroless plating. The experimental analysis showed that the surface membrane was fully dense about the thickness of 7μm. There was no interdiffusion evidence between Pd and TiAl experienced heat treatment for an enough long time at 600°C. At 500°C and the pressure difference of 0.02-0.18 MPa, the average hydrogen permeance of composite membrane was as high as 5.1 × 10^-6 mol·m^-2·s^-1· Pa^-1 and the H₂/N₂ selectivity factor was 323-400.