Preparation of palladium membrane on Pd/silicalite-1 zeolite particles modified macroporous alumina substrate for hydrogen separation

A palladium composite membrane was successfully fabricated by electroless plating on a macroporous alumina tube. Pd/silicalite-1 zeolite particles were employed to reduce the pore size of the alumina support and improve its surface roughness. Moreover, the Pd0 existed in the Sil-1 particle can avoid the time consuming sensitization and activation steps for palladium seeding. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDXS) and X-ray diffraction (XRD) analysis were conducted for analyzing the detailed microstructure of the palladium composite membrane. The hydrogen permeation performance of the resulting palladium membrane was investigated at temperatures of 623 K, 673 K, 723 K and 773 K. The hydrogen permeance of 1.95 × 10−6 mol m−2 s−1 Pa−1 with an H2/N2 ideal selectivity of 1165 for the palladium membrane was obtained at 773 K. Furthermore, the resulting palladium membrane was stable for a long-term operation of 15 days at 673 K.