The Japanese company Tanaka Precious Metal Technologies has developed a new palladium-copper membrane that achieves high hydrogen permeability at around 300 °C. It is based on an alloy called PdCu39.
Temperature matched to steam reformingHydrogen is typically produced via steam reforming of methanol-water mixtures at temperatures around 300 °C. After that, the hydrogen must be separated from other gases. Conventional membranes require temperatures of about 400 °C to operate effectively. With the new membrane, the need for additional heating systems is eliminated. This not only saves energy but also protects system components by reducing oxidation.
In addition, the technology allows for a more compact design of hydrogen purification systems.
New crystal structure makes it possibleThe high performance of the PdCu39 membrane is based on a special heat treatment process developed by Tanaka. This process enables the formation of a fully body-centered cubic (bcc) crystal structure. In contrast to the face-centered cubic (fcc) phase, the atoms in the bcc structure are less densely packed. This allows hydrogen atoms to diffuse more easily through the membrane.
Until now, it was considered difficult to achieve a pure bcc phase in PdCu39, as even small amounts of the fcc phase significantly impair hydrogen permeation. “With this development, we were able to significantly improve hydrogen permeability at lower temperatures,” the company stated. The membrane is available in various shapes and in thicknesses starting from 10 micrometers. Initial prototypes have been available to customers since September 15, 2025.
Samples available, presentation at conference in JapanTanaka presented the new membrane at the “Fall Meeting 2025” of the Japan Institute of Metals and Materials. The conference took place from September 17 to 19 at Hokkaido University.
Tanaka was founded in 1885 and is now one of the leading suppliers of precious metal products in Japan. The group employs around 5,600 people worldwide and generated sales of approximately €5.2 billion in fiscal year 2024. Tanaka specializes in industrial precious metal applications and operates research, development, and production facilities at several locations worldwide.
