1057results about "Hydrogen separation by diffusion" patented technology

The present invention provides a method and system for efficiently producing hydrogen that can be supplied to a fuel cell. The method and system of the present invention produces hydrogen in a reforming reactor using a hydrocarbon stream and water vapor stream as reactants. The hydrogen produced is purified in a hydrogen separating membrane to form a retentate stream and purified hydrogen stream. The purified hydrogen can then be fed to a fuel cell where electrical energy is produced and a fuel cell exhaust stream containing water vapor and oxygen depleted air is emitted. In one embodiment of the present invention, a means and method is provided for recycling a portion of the retentate stream to the reforming reactor for increased hydrogen yields. In another embodiment, a combustor is provided for combusting a second portion of the retentate stream to provide heat to the reforming reaction or other reactants. In a preferred embodiment, the combustion is carried out in the presence of at least a portion of the oxygen depleted air stream from the fuel cell. Thus, the system and method of the present invention advantageously uses products generated from the system to enhance the overall efficiency of the system.

A system and method for co-production of hydrogen and electrical energy. The system comprises a fuel cell assembly comprising a plurality of fuel cells. The fuel cells further comprise a cathode inlet for receiving a compressed oxidant, an anode inlet for receiving a fuel feed stream, an anode outlet in fluid communication with an anode exhaust stream and a cathode outlet in fluid communication with a cathode exhaust stream. At least a portion of the fuel feed stream reacts with the oxidant to produce electrical power. The anode exhaust stream comprises hydrogen. The co-production system further comprises a separation unit in fluid communication with the fuel cell assembly. The separation unit is configured to receive the anode exhaust stream from the fuel cell assembly to separate hydrogen from the anode exhaust stream.

Disclosed is a method of producing hydrogen from oxygenated hydrocarbon reactants, such as glycerol, glucose, or sorbitol. The method can take place in the vapor phase or in the condensed liquid phase. The method includes the steps of reacting water and a water-soluble oxygenated hydrocarbon having at least two carbon atoms, in the presence of a metal-containing catalyst. The catalyst contains a metal selected from the group consisting of Group VIII transitional metals, alloys thereof, and mixtures thereof. The disclosed method can be run at lower temperatures than those used in the conventional steam reforming of alkanes.

A process for the separation/recovery of gases is described where the desired component to be separated from the gaseous mixture is present in low/very low molar amount and/or low/moderate pressure, the process comprising contacting the gaseous mixture with a separation membrane unit containing high permeability/medium selectivity membranes which separate the feed stream into a permeate stream, enriched in the desired component and at a lower pressure and a retentate stream lean in the desired component and at a higher pressure. The retentate stream is made to convey its pressure to the permeate stream which then is directed to an adsorption PSA unit for further purification of the permeate stream so that the effluent stream from the PSA unit which contains the purified component has a purity of up to 99.90%. The process is useful for separating hydrogen from refinery off gases such as FCC gases and can also be applied to other gases such as helium and any other valuable gases present in gaseous streams in low to very low molar contents and low to moderate pressures.

Systems to convert a carbonaceous feedstock into a plurality of gaseous products are described. The systems include, among other units, four separate gasification reactors for the gasification of a carbonaceous feedstock in the presence of an alkali metal catalyst into the plurality of gaseous products including at least methane. Each of the gasification reactors may be supplied with the feedstock from a single or separate catalyst loading and/or feedstock preparation unit operations. Similarly, the hot gas streams from each gasification reactor may be purified via their combination at a heat exchanger, acid gas removal, or methane removal unit operations. Product purification may comprise trace contaminant removal units, ammonia removal and recovery units, and sour shift units.

An apparatus for producing hydrogen may include a collector of radiation to concentrate solar radiation on a converter having an absorptivity to convert the solar radiation to thermal energy to drive a chemical process using a feedstock to dissociate into an output chemical and a byproduct. A separator separates the output and byproduct, after which a reactor reacts the output to form a storage chemical, reactive to produce energy but sufficiently stable for safe handling outside designation as an energetic material. The separator may have a porosity to substantially pass hydrogen and block oxygen and water. A sweep gas may sweep hydrogen away from the separation barrier to change equilibrium. Catalysts may reduce temperature of dissociation and a subsequent reaction to combine it in a more stable, storable form.

The present invention relates to processes for preparing gaseous products, and in particular methane, via the hydromethanation of carbonaceous feedstocks in the presence of steam, carbon monoxide, hydrogen and a hydromethanation catalyst.

Integrated Combustion Reactors (ICRs) and methods of making ICRs are described in which combustion chambers (or channels) are in direct thermal contact to reaction chambers for an endothermic reaction. Superior results were achieved for combustion chambers which contained a gap for free flow through the chamber. Particular reactor designs are also described. Processes of conducting reactions in integrated combustion reactors are described and results presented. Some of these processes are characterized by unexpected and superior results.

A multi-channel modular device (10) processes between two fluid streams of different compositions. The device (10) includes a porous body (150) having a first plurality of feed-flow pathways (110) disposed in the body (150) for transporting a first stream (180). A pathway wall (114) surrounds each of the first plurality of feed-flow pathways (110) for processing the first stream (180) into a first composition (1852) and a second composition (1802). At least one feed-flow inlet (1101) is disposed in the body (150) for introducing the first stream (180) into the first plurality of feed-flow pathways (110). At least one feed-flow outlet (1102) is disposed in the body (150) for discharging the remaining first stream containing the second composition (1802). At least one second pathway (210) is disposed in the body (150) for transporting a second stream (280) having a second inlet (2101) and a second outlet (2102). A networked plurality of fluid conduits (152) formed in the porous body (150) provides the flow-conduit for the second stream (280) to sweep the first composition (1852) from each of the first plurality of the feed-flow pathways (110) to the second outlet (2102). A vessel (300) ports the inlets (1101 and 2101) and outlets (1102 and 2102) to provide a second stream flow access and for spacing the body within and away from the inner surfaces of the vessel (300) to provide a gap (310) for access. A partition (350) is disposed in the gap between the body and the vessel for diverting the flow within the gap (310).

This invention provides ways to fabricate nanotubes and nanobead arrays by utilizing nanopores in anodic aluminum oxide (AAO) membranes. Nanotubes of bismuth and other low melting point metals with controlled diameters and lengths can be fabricated by sintering AAO coated with appropriate metals at temperatures above their melting points. Carbon nanotubes may also be readily formed by carbonizing a polymer on the interior walls of the nanopores in AAO membranes. Palladium nanobead arrays which can be used as ultrafast hydrogen sensors are fabricated by coating the flat surface of AAO membranes with controlled pore-wall ratios.

A method for separating a hydrogen-rich product stream from a feed stream comprising hydrogen and at least one carbon-containing gas, comprising feeding the feed stream, at an inlet pressure greater than atmospheric pressure and a temperature greater than 200° C., to a hydrogen separation membrane system comprising a membrane that is selectively permeable to hydrogen, and producing a hydrogen-rich permeate product stream on the permeate side of the membrane and a carbon dioxide-rich product raffinate stream on the raffinate side of the membrane. A method for separating a hydrogen-rich product stream from a feed stream comprising hydrogen and at least one carbon-containing gas, comprising feeding the feed stream, at an inlet pressure greater than atmospheric pressure and a temperature greater than 200° C., to an integrated water gas shift/hydrogen separation membrane system wherein the hydrogen separation membrane system comprises a membrane that is selectively permeable to hydrogen, and producing a hydrogen-rich permeate product stream on the permeate side of the membrane and a carbon dioxide-rich product raffinate stream on the raffinate side of the membrane. A method for pretreating a membrane, comprising: heating the membrane to a desired operating temperature and desired feed pressure in a flow of inert gas for a sufficient time to cause the membrane to mechanically deform; decreasing the feed pressure to approximately ambient pressure; and optionally, flowing an oxidizing agent across the membrane before, during, or after deformation of the membrane. A method of supporting a hydrogen separation membrane system comprising selecting a hydrogen separation membrane system comprising one or more catalyst outer layers deposited on a hydrogen transport membrane layer and sealing the hydrogen separation membrane system to a porous support.

A gas separation unit 102, 200, 300 for permeating a gas out from a pressurized feed mixture includes an input manifold 104, 204, an exhaust manifold, 106, 206 and a permeate assembly 108, 208, 303. The permeate assembly supports one or more permselective foils 130, 132, 218, 232, 318 over a hollow cavity 134, 272, 306 supported by a microscreen element 142, 144, 228, 230, 326. The microscreen element includes non-porous perimeter walls 190, 192, 278 supported on a frame surface and a porous central area 194, 280 supported over the hollow cavity. A porous spacer 138, 140, 174, 234 disposed inside the hollow cavity structurally supports the entire microscreen surface spanning the hollow cavity while also providing a void volume for receiving fluid passing through the porous central area and for conveying the fluid through the hollow cavity.

The invention relates to anode exhaust gas treatment methods for solid oxide fuel cell power plants with CO2 capture, in which the unreacted fuel in the anode exhaust (301) is recovered and recycled, while the resulting exhaust stream (303) consists of highly concentrated CO2. It is essential to the invention that the anode fuel gas (102) and the cathode air (205) are kept separate throughout the solid oxide fuel cell stacks (1). A gas turbine (202,207) is included on the air side in order to maximise the electrical efficiency.

This invention provides hydrogen-permeable membranes for separation of hydrogen from hydrogen-containing gases. The membranes are multi-layer having a central hydrogen-permeable layer with one or more catalyst layers, barrier layers, and/or protective layers. The invention also relates to membrane reactors employing the hydrogen-permeable membranes of the invention and to methods for separation of hydrogen from a hydrogen-containing gas using the membranes and reactors. The reactors of this invention can be combined with additional reactor systems for direct use of the separated hydrogen.

Composite hydrogen transport membranes, which are used for extraction of hydrogen from gas mixtures are provided. Methods are described for supporting metals and metal alloys which have high hydrogen permeability, but which are either too thin to be self supporting, too weak to resist differential pressures across the membrane, or which become embrittled by hydrogen. Support materials are chosen to be lattice matched to the metals and metal alloys. Preferred metals with high permeability for hydrogen include vanadium, niobium, tantalum, zirconium, palladium, and alloys thereof. Hydrogen-permeable membranes include those in which the pores of a porous support matrix are blocked by hydrogen-permeable metals and metal alloys, those in which the pores of a porous metal matrix are blocked with materials which make the membrane impervious to gases other than hydrogen, and cermets fabricated by sintering powders of metals with powders of lattice-matched ceramic.

A method and apparatus for producing hydrogen from carbonaceous materials using a hydrogen-selective permeation membrane incorporated into a carbonaceous material reactor, as a result of which, hydrogen production rate from the reactor is increased, downstream gas cleaning and purification units of conventional systems are eliminated or substantially reduced in size, and the thermal efficiency of producing hydrogen from carbon-containing materials is increased and its production cost is reduced.

A gas supplying system for fuel cell includes a reformer generating a reformed gas by reforming a mixed raw material including a fuel and a first water, a piping network distributing the reformed gas to fuel cell systems each of which is installed in different rooms or buildings, a drain recovery unit recovering a water condensed from the reformed gas in the piping network. The piping network has a circulating route. By the circulation route, the reformed gas does not stay in the piping network so that the water condensation in the piping is suppressed. The water in the piping is removed by the drain recovery unit. According to this configuration, the clogging and corrosion of the piping caused by the condensed water is avoided.