Palladium alloy membranes hydrogen permeation

Hydrogen permeation flux data (pmoles/cm -min) of activated and non-activated palladium alloy membranes... 

Corrosive reaction streams. In some application environments, the reactive or corrosive nature of one or more of the reaction components in a membrane reactor can pose a great technical challenge to the selection as well as the design of the membrane element Feed streams often contain some Impurities that may significantly affect the performance of the membrane. Therefore, attention should also be paid to the response of the selected membrane material to certain impurities in the reactant or product streams. Care should be taken to pretreat the feed streams to remove the key contaminants as far as the membrane is concerned in these cases. For example, palladium alloy membranes can not withstand sulfur- or carbon-containing compounds at a temperature higher than, say, 500 C [Kamcyama et al., 1981]. Even at lOO C, the rate of hydrogen absorption (and, therefore, permeation) in a pure palladium disk is... 

Hydrogen is able to permeate selectively through palladium or palladium alloy membranes. This has led to the demonstration of membrane reformers in the labora-... 

Palladium-based dense metallic membranes have been known to be completely selective for hydrogen permeation and are used in commercially available small-scale hydrogen purification units (e.g., Johnson Matthey, 2007 REB Research, 2007 Power + Energy, 2007 ATI Wah Chang, 2007). These hydrogen purification units typically use palladium-alloy... 

Hara, S., N. Hatakeyama, N. Itoh, H.-M. Kimura, and A. Inoue, Hydrogen permeation through palladium-coated amorphous Zr-M-Ni (M=Ti, Hf) alloy membranes, Desalination, 144,115-120, 2002. 

F.L. Chen, Y. Kinari, F. Sakamoto, Y. Nakayama and Y. Sakamoto, Hydrogen Permeation through Palladium-Based Alloy Membranes in Mixtures of 10% Methane and Ethylene in the Hydrogen , Int. J. Hydrogen Energy, 21 [7] 555-61 (1996). 

Jayaraman V., Lin Y.S. Synthesis and hydrogen permeation properties of ultrathin palladium-silver alloy membranes. J.Membr.Sci 1995 104 251-262. 

The feasibility of the palladium membrane system with an oxidation reaction on the permeation side and 1-butene dehydrogenation reaction on the reaction side in a membrane reactor has been successfully demonstrated. The palladium and its alloy membrane not only can withstand high temperature but also are selectively permeable to hydrogen... 

The very attractive feature of palladium membranes and its alloys is clearly the favorable selectivity for hydrogen permeating at high temperatures. This makes the membranes attractive for use in fuel cells. 

F. Sakamoto, Effect of carbon monoxide on hydrogen permeation in some palladium-based alloy membranes, Int. J. Hydrogen Energy 1996, 21(11/12), 1017-1024. 

In the laminated membranes, thin palladium (or palladium alloys) layer avoids the formation of oxides on the metallic surfaces resulting in a reduction of the hydrogen adsorption activation energy and, as a consequence, in an increase of the hydrogen permeation flux [55]. 

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