Dense metal membrane degradation mechanism

However, dense metal membranes present a few challenges that have, to date, prevented their widespread industrial implementation. The best performing materials, Pd and Pd-alloys, are expensive. Pure Pd displays high H2 permeability and can operate at elevated temperatures, but suffers performance degradation because of poisoning and corrosion from exposure to conmum contaminants (H2S, NH3, CO, CO2, and Hg), hydride formation, and other factors, which will be described in following sections. Pd-alloys can display better chemical stability and mechanical strength than pine Pd, but often at the expense of permeability. 

Gasification and Associated Degradation Mechanisms Applicable to Dense Metal Hydrogen Membranes... 

Morreale B, Cifemo J, Howard B, Ciocco M, Marano J, lyoha O, et al. Gasification and associated degradation mechanisms applicable to dense metal hydrogen membranes. In Bose AC, editor. Inorganic membranes for energy and environmental applications. New York Springer Science + Business Media, LLC. 2009. p. 173-201. 

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