Main > GASES > Gas Separation Membranes > Org.: USA. W. (Pd Alloy: H2 Sepn.) > Work Description
Authors have been developing palladium and palladium-alloy membranes for the separation of hydrogen produced by the steam reforming process. "As the demand for hydrogen will undoubtedly increase immensely in the future, dense composite palladium--especially palladium-alloy--membranes will play an important and essential role in pure hydrogen production," author notes. "Currently, many technical issues need to be addressed, such as the development of thin membranes with good separation and long-term thermal and mechanical stability."
THE GROUP has developed unique technologies to synthesize palladium membranes that are stable for thousands of hours".
In recent work, author and colleagues investigated the hydrogen-permeability and hydrogen-selectivity stability of a low-copper-content Pd-Cu membrane with a thickness of less than 10 µm supported on a porous stainless steel substrate. "Porous stainless steel supports, unlike porous ceramic or glass supports, resist cracking," he observes. "Palladium-porous stainless steel membranes are also easily assembled, and the thermal expansion coefficient of stainless steel is very close to that of palladium, ensuring good mechanical properties of the composite membrane during temperature cycling.
"Composite Pd-Cu alloys have the advantage over other types of palladium membranes of being mechanically stable and sulfur resistant," author adds. "Pd-Cu alloys with a relatively high copper content have higher hydrogen permeability but lose their hydrogen transport properties at temperatures above 450 °C because of a phase transformation of the alloy at high temperatures."
The group measured the hydrogen permeation rate of a porous stainless-steel-supported, 10-µm-thick Pd-Cu membrane containing around 10% copper by weight and observed no decline in the rate at 450 °C over 500 hours.
Work Description's products
This section has no products