Abstract:Compared to pressure swing adsorption (PSA) and cryogenic separation methods, a membrane separation technique has superiority in simplicity and potentially less energy intensity for hydrogen separation and purification. To date, high purity of hydrogen is obtainable through dense metallic membranes, especially palladium and its alloys in industry. However, Pd-based alloy membranes are very expensive in large-scale industrial application. The application of non-palladium-based dense metallic separation membranes is currently receiving great attention. The mechanism of hydrogen separation, composition and current progress of non-palladium-based metallic membranes were reviewed, and the existing problems were identified.