Stability of pore-plated membranes for hydrogen production in fluidized-bed membrane reactors.

Pd-based membranes prepared by pore-plating technique have been investigated for the first time under fluidization conditions. A palladium thickness around 20 μm was achieved onto an oxidized porous stainless steel support. The stability of the membranes has been assessed for more than 1300 h in gas separation mode (no catalyst) and other additional 200 h to continuous fluidization conditions. Permeances in the order of 5·10−7 mol s−1 m−2 Pa−1 have been obtained for temperatures in a range between 375 and 500 °C. During fluidization, a small decrease in permeance is observed, as consequence of the increased external (bed-to-wall) mass transfer resistances. Moreover, water gas shift (WGS) reaction cases have been carried out in a fluidized bed membrane reactor. It has been confirmed that the selective H 2 separation through the membranes resulted in CO conversions beyond the thermodynamic equilibrium (of conventional systems), showing the benefits of membrane reactors in chemical conversions. Image 1 • Novel Pd membranes prepared by pore-plate techniques are presented. • These membranes are tested under fluidizitation conditions for the first time. • Stability of these membranes is assessed for 1500 h in empty reactors. • CO conversion in the FBMR is above the one obtained in conventional reactors. [ABSTRACT FROM AUTHOR]