Study of Microstrain and Stress in Non-Planar Palladium Membranes for Hydrogen Separation


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Palladiums tubular membranes are developed to operate up to 400 °C, for the synthesis of H2 and for the separation of CO2 in Water Gas Shift (WGS) processes and reforming gas of methane [. Palladium has FCC lattice that allows the separation of hydrogen from carbon dioxide through a solution-diffusion mechanism [. To ensure high selectivity in the separation process, the functional Pd layer on the porous substrate of the membranes must have a microstructure with low defects and free from residual stresses [.MicroXRD measurements were performed to evaluate the effect of the stress-relief heat treatment, carried out for different time and temperatures, on the palladium layer. Microstrains were assessed before and after stress-relief by the Williamson-Hall method [. The use of microdiffraction was mandatory considering the tubular shape of membranes. The data were corrected for elastic anisotropy of palladium and the altered Williamson-Hall method was successfully applied.The XRD two-dimensional (2D) images and the integrated spectra collected from the samples allowed to study also the evolution of Pd microstructure and the reduction of micro-stresses due to stress relief. The results of the study allowed to identify the optimal thermal profile for the heat treatment of palladium membranes.



Main Theme:

Edited by:

M. François, G. Montay, B. Panicaud, D. Retraint and E. Rouhaud




M. Brisotto et al., "Study of Microstrain and Stress in Non-Planar Palladium Membranes for Hydrogen Separation", Advanced Materials Research, Vol. 996, pp. 27-32, 2014

Online since:

August 2014


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