Hydrogen purification devices, components and fuel processing systems containing the same

A hydrogen purification device, comprising:

• an enclosure defining an internal compartment, wherein the enclosure includes at least one input port through which a mixed gas stream containing hydrogen gas and other gases is delivered to the enclosure, at least one product output port through which a permeate stream containing at least substantially pure hydrogen gas is removed from the enclosure, and at least one byproduct output port through which a byproduct stream containing at least a substantial portion of the other gases is removed from the enclosure;
• at least one membrane envelope within the compartment, wherein each membrane envelope is formed from a pair of hydrogen-selective membranes, wherein each membrane includes a first surface adapted to be contacted by the mixed gas stream and a permeate surface generally opposed to the first surface, wherein the pair of membranes are oriented such that the pair of hydrogen-selective membranes are spaced-apart from each other with their permeate surfaces generally facing each other to define a harvesting conduit extending therebetween, wherein each membrane envelope further includes a support within the harvesting conduit and adapted to support the pair of hydrogen-selective membranes, wherein the support includes a pair of generally opposed surfaces that are respectively adapted to provide support to the permeate surfaces of the pair of hydrogen-selective membranes, wherein the permeate stream is formed from the portion of the mixed gas stream that passes through the membranes to the harvesting conduit, with at least a portion of the mixed gas stream that does not pass through the membranes forming at least a portion of the byproduct stream;
• and further wherein each of the hydrogen
• selective membranes has a coefficient of thermal expansion;
• and
• means for supporting the at least one membrane envelope within the enclosure, wherein the means for supporting the at least one membrane envelope within the enclosure includes a membrane-contacting structure that has a different composition than the hydrogen-selective membranes and at least one of a coefficient of thermal expansion that is less than the coefficient of thermal expansion of the hydrogen-selective membranes and a composition that includes an alloy comprising nickel and copper.