An integrated process for making high molecular weight hydrocarbons from a synthesis gas feed to a Fischer-Tropsch unit. A carbon monoxide resistant gold-on-palladium membrane system (membrane system) is used to control the hydrogen-to-carbon monoxide molar ratio of a feed to the Fischer-Tropsch unit. The membrane system is operatively connected between a steam reformer and the Fischer-Tropsch unit. The membrane system receives a synthesis gas stream and provides for the removal of hydrogen from the synthesis gas stream to provide a retentate stream having a desired H.sub.2/CO molar ratio that is fed to the Fischer-Tropsch unit.

Methods and systems for the separation of isotopes from an aqueous stream are described as can be utilized in one embodiment to remove and recover tritium from contaminated water. Methods include counter-current flow of an aqueous stream on either side of a separation membrane. The separation membrane includes an isotope selective layer (e.g., graphene) and an ion conductive supporting layer (e.g., Nafion). An electronic driving force encourages passage of isotopes selectively across the membrane to enrich the flow in the isotopes.

The present invention relates to processes utilizing hydrogen species selectively permeable membranes for synthesis of products. The present invention also relates to processes for synthesizing products from hydrogen insertion or hydrogenation reactions utilizing hydrogen species permeable membranes. The present invention also relates to processes for synthesizing ammonia utilizing hydrogen species selectively permeable membranes. The membranes provide surfaced modified membranes that can comprise a porous layer containing a plurality of reactive sites comprising a metal species and a catalyst for promoting a reaction within the layer.

Disclosed is a method and plant for the catalytic dehydrogenation of alkanes, such as propane. The plant is a plant of hybrid architecture wherein one or more membrane-assisted reactor configurations according to open architecture are combined with one or more membrane-containing reactors of closed architecture. Hydrogen remaining in the reaction mixture after separation in the membrane separation unit of a first open architecture configuration, is fed to a first membrane-reactor of the closed architecture type. Also disclosed are methods of modifying plants so as to create the hybrid architecture plant.

Gas separation modules and methods for use including an integrated adsorbent and membrane. In certain refining applications, it is paramount to obtain high purity product gases. Adsorbent beds are effective at removing certain contaminants, such as CO.sub.2, from gas streams containing product and contaminant constituents to form a product-rich stream. The integrated membrane permits a further separation of products from any unadsorbed contaminant to produce a high purity product, such as hydrogen, stream. The gas separation modules described herein include stacked, radial, and spiral arrangements. Each modules includes a configuration of feed and cross-flow channels for the collection of contaminant gases and/or high purity product gases.

A filtration filter is suitable for performing cross-flow filtration by using a metallic porous membrane. A metallic porous membrane has a membrane portion for filtering filtration objects contained in a fluid and a held portion provided at its outer periphery. A first frame member and a second frame member hold the held portion of the metallic porous membrane there between. The held portion has a bent portion bent to a second principal surface side opposing a first principal surface of the membrane portion. The first frame member is in contact with the held portion at the first principal surface side of the metallic porous membrane. The second frame member is disposed at an inner side portion of the first frame member and is in contact with the held portion at the second principal surface side of the metallic porous membrane.

A method for preparing a palladium-gold alloy layer on a substrate by electrodepositing said coating surface with an aqueous electroplating solution comprising of an aqueous solution of a soluble palladium compound and a soluble gold complex, wherein the ratio of gold to palladium to in the solution is from 5 to 40 w/w %. Also taught is a substrate such as a vanadium or vanadium alloy gas separation membrane coated with a palladium-gold alloy layer.

An apparatus includes a porous substrate and a multi-layer membrane. The porous substrate has a pore structure configured to allow diffusion of hydrogen molecules through the porous substrate. The multi-layer membrane is configured to, in response to contacting a hydrogen molecule present in the gas stream, split the hydrogen molecule into at least one of hydrogen atoms or protons. The multi-layer membrane is configured to allow passage of the hydrogen atoms or protons through the multi-layer membrane while blocking passage of compounds that may be present in the gas stream that are larger than hydrogen molecules. The hydrogen atoms or protons, after passing through the multi-layer membrane, combine to reform the hydrogen molecule. The multi-layer membrane includes a first metallic layer, an intermediate layer, and a second metallic layer.

A composite metal membrane for use in hydrogen purification includes a body-centered cubic metal layer, one or more catalyst layers, and one or more hydrogen-permeable, intermetallic diffusion barriers deposited between the body-centered cubic metal layer and the one or more catalyst layers. The body-centered cubic metal layer can include a group 5 metal. The one or more hydrogen-permeable, intermetallic diffusion barriers can each include a group 4 nitride, which may be applied via reactive sputtering. The one or more catalyst layers can each include a platinum group metal. The composite metal membrane may be symmetric in configuration, with a first hydrogen-permeable, intermetallic diffusion barrier between the body-centered cubic metal layer and a first catalyst layer, and a second hydrogen-permeable, intermetallic diffusion barrier between the body-centered cubic metal layer and a second catalyst layer.

A method for low hydrogen content separation from a natural gas mixture includes the following steps: a) providing a stream having hydrogen; b) transferring the stream having hydrogen of a) as an inlet stream to a first membrane unit for obtaining a retentate and a permeate, wherein the molar fraction of hydrogen in the permeate is higher that the molar fraction of hydrogen in the retentate, c) transferring the retentate to an electrochemical hydrogen compressor (EHC) for further hydrogen separation and purification.