Realizing stable high hydrogen permeation flux through BaCo0.4Fe0.4Zr0.1Y0.1O3-δ membrane using a thin Pd film protection strategy

Abstract

Hydrogen (H2)-selective membrane is an enabling technology for high purity H2 production from natural gas. Here, we demonstrate the feasibility to apply BaCo0.4Fe0.4Zr0.1Y0.1O3-δ (BCFZY), a widely studied MPEC composition with high electronic conductivity as H2 permeation membrane by sputtering thin Palladium (Pd) films on its feed and permeate surfaces as a protective layer to prevent BCFZY reduction upon long-term exposure to reducing H2. Pd thin film also acts as a catalytic layer to enhance H2 dissociation in the feed surface and H association in the permeate surface. Pd-sputtered BCFZY (Pd|BCFZY|Pd) membrane displayed exceptionally high H2 flux that varies from 0.101 rise to 0.213 mL min−1 cm−2 (450 °C–650 °C) under the 10% H2-90% N2/Argon (Ar) gradient. The attainment of significant H2 permeability below 500 °C shown here indicates the possibility to lower the operating temperature for H2 permeation using MPEC materials. Pd|BCFZY|Pd membrane also demonstrated stable, high H2 flux that fluctuates more or less 0.138 mL min−1 cm−2 during the continuous operation over 225-h duration.