Abstract: A method of making a membrane permeable to hydrogen gas (H2?) is disclosed. The membrane is made by forming a palladium layer, depositing a layer of copper on the palladium layer, and galvanically displacing a portion of the copper with palladium. The membrane has improved resistance to poisoning by H2S compared to a palladium membrane. The membrane also has increased permeance of hydrogen gas compared to palladium-copper alloys. The membrane can be annealed at a lower temperature for a shorter amount of time.

Abstract: Composite structures are described that have a porous anodic oxide layer such as, for example, a porous anodic aluminum oxide layer. In one aspect, the present invention includes a composite gas separation module having a porous metal substrate; a porous anodic aluminum oxide layer, wherein the porous anodic aluminum oxide layer overlies the porous metal substrate; and a dense gas-selective membrane, wherein the dense gas-selective membrane overlies the porous anodic aluminum oxide layer. A composite filter is described having a porous non-aluminum metal substrate; and a porous anodic aluminum oxide layer, wherein the porous anodic aluminum oxide layer defines pores extending through the porous anodic aluminum oxide layer. Methods for fabricating composite gas separation modules and composite filters and methods for selectively separating hydrogen gas from a hydrogen gas-containing gaseous stream are also described.

Abstract: A method of making a membrane permeable to hydrogen gas (H2?) is disclosed. The membrane is made by forming a palladium layer, depositing a layer of copper on the palladium layer, and galvanically displacing a portion of the copper with palladium. The membrane has improved resistance to poisoning by H2S compared to a palladium membrane. The membrane also has increased permeance of hydrogen gas compared to palladium-copper alloys. The membrane can be annealed at a lower temperature for a shorter amount of time.

Abstract: Composite structures are described that have a porous anodic oxide layer such as, for example, a porous anodic aluminum oxide layer. In one aspect, the present invention includes a composite gas separation module having a porous metal substrate; a porous anodic aluminum oxide layer, wherein the porous anodic aluminum oxide layer overlies the porous metal substrate; and a dense gas-selective membrane, wherein the dense gas-selective membrane overlies the porous anodic aluminum oxide layer. A composite filter is described having a porous non-aluminum metal substrate; and a porous anodic aluminum oxide layer, wherein the porous anodic aluminum oxide layer defines pores extending through the porous anodic aluminum oxide layer. Methods for fabricating composite gas separation modules and composite filters and methods for selectively separating hydrogen gas from a hydrogen gas-containing gaseous stream are also described.

Abstract: A method for fabricating a composite gas separation module includes depositing a preactivated powder over a porous substrate; depositing a binder metal onto the preactivated powder; and depositing a dense gas-selective membrane to overlie the preactivated powder and binder metal, thereby forming the composite gas separation module. The preactivated powder can be, for example, selected from the group consisting of preactivated metal powders, preactivated metal oxide powders, preactivated ceramic powders, preactivated zeolite powders, and combinations thereof. The preactivated powder can be deposited, for example, from a slurry such as a water-based slurry. In some embodiments, the dense gas-selective membrane is a dense hydrogen-selective membrane.

Abstract: The present invention relates to a method for fabricating a composite gas separation module and to gas separation modules formed by the method. In one embodiment, the method for fabricating a composite gas separation module includes depositing a first material on a porous substrate, thereby forming a coated substrate. The coated substrate is abraded, thereby forming a polished substrate. A second material is then deposited on the polished substrate. The first material, the second material, or both the first material and the second material can include a gas-selective material such as a hydrogen-selective metal, e.g., palladium, or an alloy thereof. In one embodiment, the method includes the step of forming a dense gas-selective membrane over the porous substrate. The present invention also relates to a method for selectively separating hydrogen gas from a hydrogen gas-containing gaseous stream.

Abstract: A composite gas separation module includes a porous metal substrate; an intermediate layer that includes a powder having a Tamman temperature higher than the Tamman temperature of the porous metal substrate and wherein the intermediate layer overlies the porous metal substrate; and a dense hydrogen-selective membrane, wherein the dense hydrogen-selective membrane overlies the intermediate layer. In another embodiment, a composite gas separation module includes a porous metal substrate; an intermediate powder layer; and a dense gas-selective membrane, wherein the dense gas-selective membrane overlies the intermediate powder layer.

Abstract: The present invention relates to a composite gas separation module and to methods for fabricating a composite gas separation module. The present invention also relates to methods for selectively separating hydrogen gas from a hydrogen gas-containing gaseous stream. In one embodiment, the composite gas separation module includes a porous metal substrate; an intermediate porous metal layer, wherein the intermediate porous metal layer overlies the porous metal substrate; and a dense hydrogen-selective membrane, wherein the dense hydrogen-selective membrane overlies the intermediate porous metal layer. The intermediate porous metal layer can include palladium and a Group IB metal. For example, the intermediate porous metal layer can contain alternating layers of palladium and a Group IB metal.

Abstract: The present invention relates to a method for curing a defect in the fabrication of a composite gas separation module and to composite gas separation modules formed by a process that includes the method. The present invention also relates to a method for selectively separating hydrogen gas from a hydrogen gas-containing gaseous stream. The method for curing a defect in the fabrication of a composite gas separation module includes depositing a first material over a porous substrate, thereby forming a coated substrate, wherein the coated substrate contains at least one defect. Then, the coated substrate can be selectively surface activated proximate to the defect, thereby forming at least one selectively surface activated region of the coated substrate. A second material can be then preferentially deposited on the selectively surface activated region of the coated substrate, whereby the defect is cured.

Abstract: A composite gas separation module includes a porous metal substrate; an intermediate layer that includes a powder having a Tamman temperature higher than the Tamman temperature of the porous metal substrate and wherein the intermediate layer overlies the porous metal substrate; and a dense hydrogen-selective membrane, wherein the dense hydrogen-selective membrane overlies the intermediate layer. In another embodiment, a composite gas separation module includes a porous metal substrate; an intermediate powder layer; and a dense gas-selective membrane, wherein the dense gas-selective membrane overlies the intermediate powder layer.

Abstract: The present invention relates to a method for curing a defect in the fabrication of a composite gas separation module and to composite gas separation modules formed by a process that includes the method. The present invention also relates to a method for selectively separating hydrogen gas from a hydrogen gas-containing gaseous stream.

Abstract: The present invention relates to a method for fabricating a composite gas separation module and to gas separation modules formed by the method. The present invention also relates to a method for selectively separating hydrogen gas from a hydrogen gas-containing gaseous stream.

Abstract: The present invention relates to a composite gas separation module and to methods for fabricating a composite gas separation module. The present invention also relates to methods for selectively separating hydrogen gas from a hydrogen gas-containing gaseous stream. In one embodiment, the composite gas separation module includes a porous metal substrate; an intermediate porous metal layer, wherein the intermediate porous metal layer overlies the porous metal substrate; and a dense hydrogen-selective membrane, wherein the dense hydrogen-selective membrane overlies the intermediate porous metal layer. The intermediate porous metal layer can include can include palladium and a Group IB metal. For example, the intermediate porous metal layer can contain alternating layers of palladium and a Group IB metal.

Abstract: A hydrogen gas-extraction module includes an intermediate layer bonded between a porous metal substrate and a membrane layer that is selectively permeable to hydrogen. The metal substrate includes a substantial concentration of a first metal at a surface of the metal substrate, and the intermediate layer includes an oxide of this first metal. In one embodiment, where the module is designed to selectively extract hydrogen at high temperatures, the porous metal substrate comprises stainless steel, and the membrane layer includes palladium or a palladium/silver alloy. A method for fabricating a hydrogen gas-extraction membrane includes reacting the porous metal substrate with an oxidizing agent to form a ceramic intermediate layer on a surface of the porous metal substrate and covering the ceramic coating with the membrane layer that is selectively permeable to hydrogen.