Palladium-doped silica membrane synthesis on α-alumina support modified by γ-alumina interlayers

In this work palladium doped silica membranes were synthesized on α-alumina supports whichwere modified by coating γ-alumina layers on their surface. Two different procedures were carried out forsynthesizing palladium-doped silica membranes. In the first case four layers of silica-palladium sol werecoated (M1), and the latter, two layers of silica sol were coated followed by coating of two layers of silicapalladiumsol (M2). XRD spectra confirmed palladium presence within the structure of these membranes.The sealed membranes were tested for single gas permeance of H2, and N2 at room temperature, 100 °C,and 550 °C. Gas permeation tests revealed that no activated transport occurred for M1, as its H2, and N2permeances, and H2/N2 selectivity decreased with increasing temperature. On the contrary, M2 exhibiteddifferent behavior. In this case, H2 permeance increased and N2 permeance decreased with temperature,leading to the formation of activated molecular sieve silica membrane layer on the support.

Keywords:

Hydrogen separation , Silica membrane , Palladium-doped , Activated transport