(380ab) Quantifying Support Resistance for Composite Palladium Membranes for Hydrogen Purification

State-of-the-art membranes for hydrogen production/purification typically feature a palladium (Pd) membrane known for its high permeance, selectivity, and high temperature stability. To address the high cost of palladium, composite membranes consisting of a thin layer of Pd are deposited onto a porous support. The economics are dictated by the flux and Pd inventory. Our group recently developed an ultrasonic-assisted electroless plating process that enabled the Pd thickness to be reduced to ~1 micron while maintaining high selectivity. However, the pure hydrogen flux saturated as the membrane thickness was reduced, suggesting that performance was limited by the underlying ceramic support. In this work, we establish a framework for quantifying this support resistance and analyzing the overall performance. The support resistance was determined by measuring pressure drop against flux through a bare porous ceramic support (asymmetric yttria-stabilized zirconia), revealing a linear relationship indicative of laminar flow. This flux-dependent resistance was coupled with Sieverts’ Law and shown to effectively model the observed experimental data. This model was used to show that potential improvements could be achieved with further reductions in support resistance. We employ this model to design modifications to low resistance supports that would enable achievement of these higher performance levels.