Preparation of thin (∼2 μm) Pd membranes on ceramic supports with excellent selectivity and attrition resistance

Thin (similar to 2 mu m) Pd membranes were prepared by two-step electroless plating (ELP) method on porous ceramic supports for hydrogen purification. The two-step ELP method consists of the first ELP, the heat treatment (923 K, N-2 and 24 h) and the second ELP. The Pd composite membranes have been characterized by permeation tests with pure gas at 623-873 K and exhibited stable and highest hydrogen permeation flux (similar to 0.853 mol H-2 m(-2) s(-1)) and H-2/N-2 selectivity (similar to 88,465) at 823 K under a pressure difference of 0.1 MPa. The Pd composite membranes have been characterized by permeation tests with gas mixtures (H-2/N-2, H-2/CO2) at 623-823 K. The effect of N-2 on the hydrogen permeation flux of composite membranes was mainly due to the concentration polarization, and the effect of CO2 was due to concentration polarization at lower temperature (623 K) and a combination of the concentration polarization and chemical reactions at high temperatures (723 and 823 K). The Pd composite membranes have been characterized by attrition resistance tests with particles at 823 K and exhibited high hydrogen permeation stability and H-2/N-2 selectivity. (c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

Thin Pd membranes with a thickness of about 2 μm were prepared by a two-step electroless plating method on porous ceramic supports. The membranes exhibited stable and high hydrogen permeation flux and selectivity under different operating conditions. The effect of gas mixtures on the hydrogen permeation flux was studied, and the membranes also showed good resistance to attrition.