study of pd complexes adsorption on the γ-alooh / γ-al2o3 layer in the activation step for the preparation of palladium composite membrane

The pd composite membranes were fabricated by an improved electroless plating procedure. the wetness-impregnation technique was applied for ceramic substrate activation. the adsorption pd complex on the γ-alooh or γ-al2o3 layer was studied in this work. the obtained results showed that the pd complexes on the γ-alooh layer adsorbed more than the γ-al2o3 layer. additionally, the effect of pd precursor concentration on substrate loading was investigated. the rate of palladium deposition increases at high pd concentrations. the resulting membrane was characterized by xrd and sem-edx analysis. furthermore, permeation fluxes of the as-synthesized membrane were evaluated for various gases at different h2 pressure differences. the membrane permeance was determined to be 6.8×10-⁷mol/m².s.pa at 798 k and 1 bar under pure hydrogen. the hydrogen permeance and selectivity of hydrogen relative to other gases (ch4, co2, co, and n2) were evaluated at 773 k. all gases exhibited dilution and inhibiting (especially co) effects on hydrogen permeation. the prepared membrane does not seem damaged as the permeability recovered after treatment with pure hydrogen.