Hydrogen permeation and separation characteristics of a thin Pd-Au/Al2O3 membrane: The effect of the intermediate layer absence

摘要: Abstract The growing interest towards the hydrogen utilization as energy carrier placed a high demand on permeable membranes compact devices for separation and purification. Many studies in this scientific field demonstrated that composite Pd-based are particularly effective aforementioned purposes, if compared to of self-supported their cost mechanical limitations. As case study, membrane based thin Pd-Au (8 μm metallic layer 12 wt% Au) supported α-Al2O3 substrate was produced by electroless plating deposition. Permeation tests were performed with pure gases (H2, N2, CO2, CH4) varying temperature between 300 °C 400 °C feed pressure from 150 350 kPa. exponential factor (n-value) equation describing relationship flux permeating through its driving force analyzed function variation. An apparent activation 11 kJ/mol has been reached it is comparable other data present open literature. A H2/N2 ideal selectivity around 500 at 50 kPa transmembrane remained stable up 600 h under operation. presence defects affected performance terms H2 perm-selectivity testified post-mortem analysis exhausted membrane.