A pass or tube or a section thereof or U bend in a coil in a paraffin cracker having section having a pore size in the metal substrate from about 0.001 to 0.5 microns over coated with a dense metal membrane permits the permeation of one or more of H.sub.2, CH.sub.4, CO and CO.sub.2 from cracked gases moving the reaction equilibrium to the production of ethylene and reduces the load on the down-stream separation train of the steam cracker.

A composite membrane for hydrogen separation and purification, including: a modified and activated support, a Palladium (Pd) layer, and an interstice layer between the second surface-modifying layer and the Pd layer. The support includes a support substrate, a first surface-modifying layer on the support substrate, and a second surface-modifying layer on the first surface-modifying layer.

A hydrogen permeable membrane device is provided that includes a porous ceramic layer having a material that includes zirconia, Yttria-stabilized zirconia (YSZ), /Al.sub.2O.sub.3, and/or YSZ /Al.sub.2O.sub.3, and a porous Pd film or porous Pd-alloy film deposited on the a mesoporous ceramic layer.

Hydrogen purification devices and their components are disclosed. In some embodiments, the devices may include at least one foil-microscreen assembly disposed between and secured to first and second end frames. The at least one foil-microscreen assembly may include at least one hydrogen-selective membrane and at least one microscreen structure including a non-porous planar sheet having a plurality of apertures forming a plurality of fluid passages. The planar sheet may include generally opposed planar surfaces configured to provide support to the permeate side. The plurality of fluid passages may extend between the opposed surfaces. The at least one hydrogen-selective membrane may be metallurgically bonded to the at least one microscreen structure. In some embodiments, the devices may include a permeate frame having at least one membrane support structure that spans at least a substantial portion of an open region and that is configured to support at least one foil-microscreen assembly.

A catalytic membrane reactor and methods of operating and producing the same are provided that efficiently produces highly pure hydrogen (H.sub.2) from ammonia (NH.sub.3) as well as operates according to other chemical conversion processes. In one embodiment, a tubular ceramic support made from porous yttria-stabilized zirconia has an outer surface that is impregnated with a metal catalyst such as ruthenium and then plated with a hydrogen permeable membrane such as palladium. An inner surface of the ceramic support is impregnated with cesium to promote conversion of ammonia to hydrogen and nitrogen (N.sub.2). The resulting catalytic membrane reactor produces highly pure hydrogen at low temperatures and with less catalytic loading. Therefore, ammonia can be used to effectively transport hydrogen for use in, for example, fuel cells in a vehicle.

A method is provided for producing a foil made of an electrically conductive material. The foil consists of the same electrically conductive material along the extension of the foil thickness. A flexible substrate is first introduced into a working chamber; a layer made of the electrically conductive material is deposited on at least one surface region of the flexible substrate using a vacuum coating process; and the first layer is then removed from the flexible substrate. Either an ion-etching process is carried out at least on the surface region of the flexible substrate prior to depositing the layer made of the electrically conductive material and/or the layer made of the electrically conductive material is heated during and/or after the layer is deposited.

Hydrogen purification devices and their components are disclosed. In some embodiments, the devices may include at least one foil-microscreen assembly disposed between and secured to first and second end frames. The at least one foil-microscreen assembly may include at least one hydrogen-selective membrane and at least one microscreen structure including a non-porous planar sheet having a plurality of apertures forming a plurality of fluid passages. The planar sheet may include generally opposed planar surfaces configured to provide support to the permeate side. The plurality of fluid passages may extend between the opposed surfaces. The at least one hydrogen-selective membrane may be metallurgically bonded to the at least one microscreen structure. In some embodiments, the devices may include a permeate frame having at least one membrane support structure that spans at least a substantial portion of an open region and that is configured to support at least one foil-microscreen assembly.

A method for filtering gas includes providing a gas filtration structure, and the gas filtration structure includes a porous support and a first gas filtration film pair on the porous support, wherein the first gas filtration film pair includes a first hydrogen permeation layer and a first calcinated layered double hydroxide (c-LDH) layer, and the first hydrogen permeation layer is disposed between the porous support and the first c-LDH layer. The method also provides a hydrogen-containing mixture gas over the first gas filtration film pair, and collects hydrogen under the porous support.

Hydrogen purification devices and their components are disclosed. In some embodiments, the devices may include at least one foil-microscreen assembly disposed between and secured to first and second end frames. The at least one foil-microscreen assembly may include at least one hydrogen-selective membrane and at least one microscreen structure including a non-porous planar sheet having a plurality of apertures forming a plurality of fluid passages. The planar sheet may include generally opposed planar surfaces configured to provide support to the permeate side. The plurality of fluid passages may extend between the opposed surfaces. The at least one hydrogen-selective membrane may be metallurgically bonded to the at least one microscreen structure.

The present invention relates to a method for production of H.sub.2 from natural gas, solid fossil fuels or biomass. The method comprises the following steps: reacting natural gas in a reformer or reacting solid fossil fuels or biomass in a gasifier to form syngas, reacting the syngas to form a shifted gas mixture, comprising H.sub.2 and CO.sub.2, in a water-gas-shift (WGS) section, separating the shifted gas mixture into a H.sub.2 gas and a H.sub.2 depleted tail gas mixture or retentate gas mixture in a H.sub.2 separation unit, separating the H.sub.2-depleted tail gas mixture or retentate gas mixture into a CO.sub.2 liquid and a CO.sub.2-depleted tail gas mixture in a CO.sub.2 capture and liquefaction unit, and recycling the CO.sub.2-depleted tail gas mixture from the CO.sub.2 capture and liquefaction unit without recompression to the WGS section and to the reformer or the gasifier. The CO.sub.2-depleted tail gas mixture is at a pressure in the range from 25 to 120 bar when recycled to the WGS section and to the reformer or the gasifier.