Abstract: A purification system and method for purifying a hydrogen stream supplied from a storage tank mounted in a vehicle to produce a purified hydrogen stream for use in a PEM fuel cell system that is utilized within the vehicle. The hydrogen is purified within a membrane separator having hydrogen transport membrane elements having a dense metallic layer such as palladium to separate the hydrogen from the impurities. The separated hydrogen is supplied to the PEM fuel cell. In order to heat the membrane to its operational temperature, heat is recovered from the hydrogen permeate stream of the membrane system in a first heat exchanger and heat is generated by combusting the retentate stream containing residual hydrogen and impurities.

Abstract: A mixed ionic and electronic conducting membrane includes a two-phase solid state ceramic composite, wherein the first phase comprises an oxygen ion conductor and the second phase comprises an n-type electronically conductive oxide, wherein the electronically conductive oxide is stable at an oxygen partial pressure as low as 10?20 atm and has an electronic conductivity of at least 1 S/cm. A hydrogen separation system and related methods using the mixed ionic and electronic conducting membrane are described.

Abstract: Thin layers of a mixed composition are deposited on a porous substrate by chemical vapor deposition in an inert atmosphere at high temperature. The resulting membrane has excellent stability to water vapor at high temperatures. An exemplary membrane comprises an amorphous mixed-element surface layer comprising silica and at least one oxide of additional element, an optional porous substrate on which said surface layer is deposited, and a porous support on which said substrate or mixed-element surface layer is deposited, wherein the permeance of the membrane is higher than 1×10?7 mol m?2 s?1 Pa?1 and the selectivity of H2 over CO, CO2, and CH4 is larger than 100, and wherein the H2 permeance of the membrane after exposure to a stream containing 60 mol % water vapor at 673 K for 120 h is at least 50% of its initial H2 permeance.

Abstract: The present invention relates to the selective separation of hydrogen (“H2”) hydrocarbons in streams containing both hydrogen and hydrocarbons (e.g. methane, ethylene, ethane, propylene, propane, etc.) utilizing a zeolitic imidazolate framework (“ZIF”) material. Preferably, the stream to be separated is fed to the present process in a substantially gaseous phase. In preferred embodiments, the current invention is utilized in either a pressure swing adsorption process, a temperature swing adsorption process, or a membrane separations process to separate hydrogen from hydrocarbons present in hydrogen production streams or petrochemical/petroleum refining product streams and intermediate streams.

Abstract: A hydrogen separator is provided, including a porous substrate having a large number of pores communicating from a first surface to a second surface thereof, and having a hydrogen-separating layer disposed on the first surface so that the hydrogen-separating layer has a penetrated portion extending through the pores from the first surface to a particular depth. An average pore diameter at the first surface of the porous substrate is 0.02 to 0.5 ?m, a thickness of the hydrogen-separating layer is 1 to 5 ?m, and a penetration depth of the penetrated portion is 0.05 to 1 ?m, is at least equal to the average pore diameter at the one surface of the porous substrate, and is not larger than one half of the thickness of the hydrogen-separating layer. The hydrogen separator hardly generates defects such as cracks, peeling and the like in the hydrogen-separating layer, is superior in durability, and provides both good hydrogen-separating ability and good hydrogen permeability.

Abstract: Purified SiHCl3 is used as a sweep gas across a permeate side of a gas separation membrane receiving effluent gas from a polysilicon reactor. The combined sweep gas and permeate is recycled to the reactor.

Abstract: Effluent gas from a polysilicon reactor is directed to a gas separation membrane with a permeate gas being recycled to the reactor and the retentate being chilled with a cryogenic condenser using liquid cryogen. Liquid cryogen vaporized by the hot effluent gas may be stored or used to seal and/or chill the reactor or blanket a Si feed to a SiHCl3 reactor.

Abstract: A method of preparing a gas separation membrane system and the gas separation membrane system itself, wherein the method includes applying a layer of a gas-selective material to a porous substrate followed by heat-treating thereof in an inert gaseous atmosphere and then polishing and repeating these steps to thereby provide the gas separation membrane system or a structure that may suitably be used in a gas separation membrane system.

Abstract: An amorphous silica hybrid membrane structure comprising a monolithic inorganic porous support, optionally one or more porous inorganic intermediate layers, and an amorphous silica membrane. The amorphous silica hybrid membrane is useful for gas separation applications, for example H2 purification and CO2 capture.

Abstract: Provided is a hydrogen separation membrane prepared by compression-molding metal microparticles having hydrogen adsorbing properties, wherein the microparticles are composed of 0.5 to 50% by weight of a first metal powder and 50 to 99.5% by weight of a second metal powder having a relatively larger average particle diameter than the first metal powder.

Abstract: The present invention relates to a gas storage and dispensing system, which comprising a carrier material for a target gas and multiple microtubular elements in contact with such carrier material. Each microtubular element comprises a tubular wall that defines a bore side and a shell side that are sealed from each other, preferably by one or more potting members. The carrier material is either at the bore sides or at the shell sides of the microtubular elements, and it can be either a solid sorbent material for the target gas, or a liquid carrier therefor. Such gas storage and dispensing system is particular useful for hydrogen storage, when the carrier material can be a hydrogen-sorbent that contains hydrogen gas, or liquefied hydrogen, or an organic hydrogen solution, or a metal hydride solution capable of generating hydrogen gas. Such microtubular elements can further be designed as microfibrous fuel cells, while each microfibrous fuel cell comprises a carrier material at its bore side.

Abstract: Methods for treating a gas mixture of at least propylene and propane, in order to separate the propylene from the propane. The gas mixture is brought into contact with a membrane enables the selective permeation of the propylene with respect to the propane. A propylene-enriched permeate and a propane-enriched retentate is formed. The propylene concentration of the permeate in the membrane is then reduced with a sweeping gas.

Abstract: This invention describes a new hydrogen purification process that employs a combination of at least three membrane separation units. This process allows non-stationary operations and is particularly suitable for the production of hydrogen for the purpose of its use in a fuel cell.

Abstract: System and method for supplying reductants to an emission treatment system. The system includes a fuel tank adapted to supply a premixed fuel stream that includes a primary component and a reductant component, and an engine in fluid communication with the fuel tank, wherein the engine is configured to create an emission. The engine includes an emission treatment system to treat the emission. The system also includes a separation system that includes a membrane with differential permeability for the reductant component relative to the primary component. The separation system is configured to receive at least a portion of the premixed fuel stream from the tank and to separate the premixed fuel stream into a first fraction and a second fraction. The first fraction includes a higher concentration of the reductant component than the second fraction, and the separation system is configured to supply the first fraction to the emission treatment system.

Abstract: The present invention is for novel high performance cross-linkable and cross-linked mixed matrix membranes and the use of such membranes for separations such as for CO2/CH4, H2/CH4 and propylene/propane separations. More specifically, the invention involves the preparation of cross-linkable and cross-linked mixed matrix membranes (MMMs). The cross-linkable MMMs were prepared by incorporating microporous molecular sieves or soluble high surface area microporous polymers (PIMs) as dispersed microporous fillers into a continuous cross-linkable polymer matrix. The cross-linked MMMs were prepared by UV-cross-linking the cross-linkable MMMs containing cross-linkable polymer matrix such as BP-55 polyimide. Pure gas permeation test results demonstrated that both types of MMMs exhibited higher performance for CO2/CH4 and H2/CH4 separations than those of the corresponding cross-linkable and cross-linked pure polymer matrices.

Abstract: Disclosed are processes for preparing conductive glass-ceramic membranes.

Abstract: An Ni—Ti—Nb based multiple phase alloy consists of a combined phase which comprises a phase for the hydrogen permeability and a phase for the resistance to hydrogen embrittlement. The alloy has a composition satisfying the formula: NixTiyNb(100-x-y) in which x=25˜45 mol % and y=25˜55 mol %. A metal membrane for hydrogen separation-purification is prepared using the alloy material. The alloy material is prepared by blending Ni, Ti and Nb and melting the blend. The metal membrane permits the hydrogen separation-purification and thus the resulting purified hydrogen gas can be used as a fuel and can be applied to fields of production of semiconductors.

Abstract: The present invention relates to a polymer blend membrane comprising a bridged polymer which is produced by a selected process. The membrane of the invention displays a significantly improved fracture toughness (elongation at break/stress) combined with virtually unchanged other properties. The membranes of the invention are suitable for producing membrane-electrode units for fuel cells.

Abstract: The invention relates to a composite structure consisting of a relatively long filtration bar comprising, from the outside, an ultra-thin layer (26) that is selectively permeable to hydrogen and made from palladium or silver alloy. Said layer is disposed on a permeable, rigid, refractory substrate consisting of a more or less solid body (30) that is covered with an intermediary thin layer (28) having a relatively smooth surface. The body (30) and the intermediary layer (28) are made respectively by sintering with fine and ultra-fine Inconel grains. A rigid metallic axial structure (32) is embedded in the body (30). Veinlets (31), which are made in the body (30) through the destruction of thermo-destructible wires during sintering, increase the permeability of the substrate. The invention is particularly applicable to hydrogen-producing combustible gas processors.

Abstract: This abstract discusses membranes needed to separate fluids for the production of oxygen-enriched air, nitrogen-enriched-air, for the separation of carbon dioxide from hydrocarbons, and the separation of hydrogen from various petrochemical and oil refining streams. Membranes are needed that provide a resistance to interaction with process components or contaminants, provide the mechanical strength required to withstand high membrane differential pressures and high process temperatures, and exhibit sufficient maximum strain such that membranes are not brittle and can easily be formed into desirable membrane forms. Membranes of polyimide polymers, particularly polyimide polymers sold under the trade name P-84, are annealed in a controlled annealing step to improve the mechanical properties of the polymers used to make separation membranes.

Abstract: In the present invention, a solution containing a target substance is atomized into a mist in an atomizer 1 to produce a mixed fluid of mist and gas. In the collection of the mist from this mixed fluid, a gas transmission membrane 51 of a pore size is used that transmits gas but does not transmit the target substance contained in the mist. In the present invention, the mixed fluid is brought into contact with the primary surface of the gas transmission membrane 51, and the pressure on the primary surface is made higher than the pressure on the secondary surface of the opposite side, whereby the gas in the mixed fluid is let to pass through the gas transmission membrane 51 to separate part or all of the gas contained in the mixed fluid.

Abstract: Improved solid acid electrolyte materials, methods of synthesizing such materials, and electrochemical devices incorporating such materials are provided. The stable electrolyte material comprises a solid acid capable undergoing rotational disorder of oxyanion groups and capable of extended operation at elevated temperatures, that is, solid acids having hydrogen bonded anion groups; a superprotonic, trigonal, tetragonal, or cubic, disordered phase; and capable of being operating at temperatures of ˜100° C. and higher.

Abstract: The present invention generally relates to electrochemical systems for producing hydrogen and/or power. Various aspects of the invention are directed to reactor designs for producing hydrogen and/or power from a fuel and water, conducting ceramics and other materials for such systems, including mixed ionically and electrically conducting ceramics which can be used for hydrogen gas generation, control systems for such systems, and methods of operating such systems.

Abstract: A system and method of purifying hydrogen gas. The system includes heating elements for heating the hydrogen diffusion cell to a predetermined operational temperature. A preheater is provided for heating unpurified gases that will enter the hydrogen diffusion cell. The unpurified gases are heated to the operational temperature of the hydrogen diffusion cell before entering the hydrogen diffusion cell. In this manner, the inflow of unpurified gases into the hydrogen diffusion cell does not cause any thermal shock to the hydrogen diffusion cell. The incoming unpurified gases are heated in two ways. The unpurified gases are heated in a preheater. The unpurified gases are also heated in a heat exchanger. The heat exchanger recycles the heat from the purified hydrogen gas.

Abstract: There is disclosed a method of making a high performance carbon membranes from polymer membranes. The method comprising the steps of exposing polymer precursor compounds to a polar organic liquid before pyrolysis of the exposed polymer precursor compounds.

Abstract: A method for purification of a gaseous stream having at least one impurity in which a porous material having at least one polyoxometalate-based material is contacted with the gaseous stream and the at least one impurity is passed through the porous material, producing a purified gaseous stream.

Abstract: A hydrogen purification method that is used to separate hydrogen gas from a source gas. A hydrogen separator into which flows the source. Within the hydrogen separator is at least one hydrogen permeable tube that is made of a hydrogen permeable material. A support tube is provided for each hydrogen permeable tube. A support tube is coaxially aligned with the hydrogen permeable tube, wherein a micro-channel exists between the hydrogen permeable tube and the support tube in an area of overlap. The source gas is introduced into the micro-channel. The source gas spreads thinly over the hydrogen permeable tube in the micro-channel. The restrictions of the micro-channel cause the source gas to embody turbulent flow characteristics as it flows through the micro-channel. The turbulent flow causes the hydrogen separator to separate hydrogen from the source gas in a highly efficient manner.

Abstract: A fuel cell gas separator (14) between two planar solid oxide fuel cells (12) comprises a first layer (22) which is formed of a material that is impermeable to gases, a second layer (24) which is formed of a material that is impermeable to gases. The first and second layers have perforations (28) through their thickness which are closed by electrically conductive plug material (30). A third intermediate layer (26) between the first and second layers is electrically conductive and is in electrical contact with the plug material in the perforations through the first and second layers. The perforations in the first layer may be offset relative to the perforations in the second layer. The electrically conductive plug material in the perforations of the first and second layers may be the same, and may also be the same as the material of the third intermediate layer. The electrically conductive material may be silver or a silver-based material such as a silver-glass composite.

Abstract: A hydrogen purification system that is used to separate hydrogen gas from a source gas. The hydrogen purification system has a hydrogen separator into which the source gas is permitted to flow. Within the hydrogen separator is at least one hydrogen permeable tube that is made of a hydrogen permeable material. A support tube is provided for each hydrogen permeable tube. A support tube is coaxially aligned with the hydrogen permeable tube, wherein a gap space exists between the hydrogen permeable tube and the support tube in an area of overlap. The source gas is introduced into the gap space. The source gas spreads thinly over the hydrogen permeable tube in the gap space. Hydrogen from the source gas passes through the hydrogen permeable tube in a highly efficient manner and is collected.

Abstract: A process for purification of hydrogen from a stream of synthesis gas or other reformate gases is described. The process, generally conducted at temperatures of approximately 800-1000° C., involves the use of a cell in which a mixture of reformate gas and steam are flowed on one side of a dense solid state ceramic membrane, while steam is passed on the other side. High purity hydrogen is generated on the steam side. The membrane is similar to one that has in the past been used for oxygen purification and can be single or two phase, for example La0.9Sr0.1Ga0.8Mg0.2O3+Pd.

Abstract: According to the present invention there is disclosed a hydrogen-permeable membrane which comprises a ceramic material composed of a nitride of aluminum (Al) and/or silicon (Si), an oxide of aluminum (Al) and/or silicon (Si), or a silicide of a rare earth element, and particles of at least one kind of hydrogen-permeable metal selected from palladium (Pd), niobium (Nb), vanadium (V), tantalum (Ta) and an alloy thereof, dispersed in the ceramic material, wherein a proportion of the hydrogen-permeable metal particles in the hydrogen-permeable membrane is 30 to 70% by mass and a thickness of the membrane is 5 to 1,000 nm.

Abstract: An apparatus for separation or synthesis of process substances is configured with at least two cell stacks, within each of which there is arranged at least one large-area layer for the separation or synthesis and passages are formed for feeding and discharging at least one process substance to or from the at least one layer. To ensure that the ratio of active surface area to total area of the layer is as high as possible yet on the other hand that uniform distribution of at least one process substance over the layer are ensured, at least two passages for a process substance are formed within at least a first cell stack, of which a first passage is used to pass the process substance through the first cell stack to a second cell stack and of which the second passage is used to feed or discharge the process substance to or from the at least one layer in the first cell stack.

Abstract: The present invention relates to composite structured adsorbents and methods of use therefor. The invention more particularly relates to composite structured adsorbents that can include a multi-channel framework (e.g., monoliths), the channels of the multi-channel framework containing adsorbent beads particles therein, with a channel-to-particle diameter ratio in the range of 1 to 10, more preferably 1 to 7 and even more preferably 1 to 5. In the case of non-spherical particles, the hydraulic diameter is used in the calculation of the channel-to-particle diameter. The composite structured adsorbents of the present invention can be used in various industrial applications, for example in pressure swing adsorption (PSA) or vacuum pressure swing adsorption (VPSA) processes to produce O2 from air.

Abstract: Methods and apparatus are taught for selectively oxidizing carbon monoxide in a source of gas containing carbon monoxide and hydrogen. A gas containing carbon monoxide and hydrogen is fed into a membrane reactor (10, 50, 60) capable of selectively absorbing the carbon monoxide. Preferably, the reactor comprises a substantially defect-free zeolite membrane (4) having at one metal that acts as an oxidation catalyst. The zeolite membrane (4) may be supported on a porous ceramic support (2, 52, 61) and the average pore diameter is preferably between about 0.3 nm and about 1.0 nm. Moreover, the substantially defect-free zeolite membrane (4) preferably has a thickness between about 0.1 micron and about 50.0 microns. The at least one metal is preferably capable of selectively oxidizing the carbon monoxide and is preferably platinum. Preferably, the temperature of reactor housing is maintained at about 200-300° C.

Abstract: An asymmetric hollow-fiber gas separation membrane is made of a soluble aromatic polyimide that is composed of a specific repeating unit. The tetracarboxylic acid component of the unit has a diphenylhexafluoropropane structure and a biphenyl structure. The diamine component of the unit essentially contains diaminobenzoic acids and any of diaminodibenzothiophenes, diaminodibenzothiophene=5,5-dioxides, diaminothioxanthene-10,10-diones, and diaminothioxanthene-9,10,10-triones.

Abstract: A hydrogen reforming system includes a cyclical compression chamber having an entry port for receiving hydrogen-containing gas and an exit port for delivering reformed hydrogen-containing gas, an arrangement for heating the hydrogen-containing gas to a non-combustible temperature, and a drive system for cycling the cyclical compression chamber. The cyclical compression chamber has an operational cycle with an internal pressure and temperature absent combustion effective for reforming the hydrogen-containing gas.

Abstract: Thermally tuned lasers may use a resistive thermal device (RTD), sensitive to hydrogen, within a hermetic enclosure. Over time, hydrogen trapped within the enclosure or out gassed from other components within the enclosure may degrade the accuracy of the RTD. A vent comprising a hydrogen selective permeable membrane, such as palladium or a palladium alloy, provided in the enclosure vents hydrogen to mitigate damage to the RTD.

Abstract: The present invention provides for a process for producing carbon monoxide. A feed gas stream of hydrogen, carbon monoxide and carbon dioxide is directed to a membrane unit which separates the feed gas stream into two streams. The stream containing carbon monoxide is directed to second membrane unit for further purification and the steam containing the carbon dioxide and hydrogen is fed to a reverse shift reactor to produce more carbon monoxide. The carbon monoxide recovered from the reverse shift reactor is purified in a third membrane unit and directed back to the first membrane unit and is further purified and recovered as additional carbon monoxide product.

Abstract: A membrane module for the separation of hydrogen is configured for parallel flows and contains a plurality of planar membrane cells which respectively comprise two hydrogen-selective planar membranes respectively surrounded by a flat membrane frame. An air-permeable distancing layer is arranged between the membranes for removal of the permeate gas and a supply frame surrounding a supply area for the reformate gas. All membrane frames and supply frames have the same outer dimensions and form a stack with planar side surfaces. Two membrane frames of each membrane cell have protruding edges directed towards each other, enabling them to enter into contact with each other, except for at least one first opening towards a side surface of the stack. The supply frame is disposed, except for second and third openings towards the side surfaces of the stack, in a closely adjacent manner to the edges of the membrane frame of two neighboring membrane cells.

Abstract: A hydrogen permeation membrane is provided having a cP2 Pearson symbol (Pm3m space group) structure. Suitable alloys include an “A” element from Periodic Table groups 3b-5b and an “M” element from the Periodic Table groups 6b-1b present at a stoichiometry that achieves the inventive crystal structure. Zr and Nb are the preferred A elements followed in preference by Ti and V. First Periodic Table row elements from groups 6b-1b are the preferred B elements. The inventive alloys also find applications as hydrogen getters, Ni-metal hydride battery materials, and hydrogen storage materials.

Abstract: A gas separator, a method for producing the gas separator, and a method for separating gases based on a property of inelasticity of the gases. The inventive gas separator is a permeable porous material for separating a mixture of gases by selectable pore size exclusion, comprising pores formed with at least one nanostructured compound. In other words, the inventive porous material can be used to separate a mixture of gases based upon the different working diameter of each of the gases. By selecting specific nanostructured compounds, the porous material can be tailored to contain pores of a predetermined size which allow gases having a working diameter smaller than the size of the pores to pass through the material while preventing the passage of gases having a working diameter greater than the size of the pores.

Abstract: Hydrogen purification devices, components thereof, and fuel processors and fuel cell systems containing the same. The hydrogen purification devices include an enclosure, such as a pressure vessel, that contains a separation assembly adapted to receive under pressure a mixed gas stream containing hydrogen gas and to produce a stream that contains pure or at least substantially pure hydrogen gas therefrom. In some embodiments, the enclosure is sealed without gaskets. The separation assembly includes at least one hydrogen-permeable and/or hydrogen-selective membrane, and in some embodiments the hydrogen-selective membrane is permanently and directly secured to the enclosure. In some embodiments, the membrane is welded, diffusion bonded or brazed directly to the enclosure. In some embodiments a portion of the hydrogen-selective membrane forms a portion of the sealed enclosure, and, in some embodiments, an interface is formed from consumed portions of the hydrogen-selective membrane and the enclosure.

Abstract: The present invention relates to a solid multicomponent mixed proton and electron conducting membrane for use in a reactor, where the membrane comprises a mixed metal oxide having a structure represented by the formula: A1?xA?x(B1?yB?y)wO3?d, wherein A is a lanthanide element or mixtures thereof, A? is an alkaline earth element or mixtures thereof, B is chromium, manganese, or iron, B? is titanium, aluminum, zirconium, or hafnium, and x, y, w, and d each represent a number such that 0?x?1, 0?y?1, 0.9<w<1.1, and d equals a number that renders the compound charge neutral and is not less than zero and not greater than about 0.6.

Abstract: A multi-phase mixed protonic/electronic conducting material comprising a proton-conducting ceramic phase and an electron conductive ceramic phase. Under the presence of a partial pressure gradient of hydrogen across the membrane, a membrane fabricated with this material selectively transports hydrogen ions through the protonically conductive ceramic phase and electrons through the electronically conducting ceramic phase, which results in ultrahigh purity hydrogen permeation through the membrane. The material has a high electronic conductivity and hydrogen gas transport is rate-limited by the protonic conductivity of the material.

Abstract: In order to recover hydrogen from a hydrogen-rich gaseous effluent, a procedure is used that comprises: in a stage (a), bringing a hydrocarbon-rich gaseous effluent into contact with the upstream face of a hydrogen-selective membrane at a pressure P1; in a stage (b), bringing a flow containing one or more unsaturated compound(s) into contact with the downstream face of a membrane at a pressure P2, which is smaller than P1, in the presence of a catalyst, to hydrogenate at least a portion of the unsaturated compound(s) using at least a portion of the hydrogen that passes by permeation through the upstream face to the downstream face of the selective membrane; and in a stage (c), transporting a flow containing the hydrogenated compound(s) into stage (b).

Abstract: A device and method for separating water into hydrogen and oxygen is disclosed. A first substantially gas impervious solid electron-conducting membrane for selectively passing protons or hydrogen is provided and spaced from a second substantially gas impervious solid electron-conducting membrane for selectively passing oxygen. When steam is passed between the two membranes at dissociation temperatures the hydrogen from the dissociation of steam selectively and continuously passes through the first membrane and oxygen selectively and continuously passes through the second membrane, thereby continuously driving the dissociation of steam producing hydrogen and oxygen. The oxygen is thereafter reacted with methane to produce syngas which optimally may be reacted in a water gas shift reaction to produce CO2 and H2.

Abstract: A method for separating gases within a barrier, and a metallic barrier separating the gases is provided for use in solid oxide fuel cells, or SOFC. A network of pores can vent steam formed within the barrier by the reaction of hydrogen diffusing from one side and oxygen diffusing from the other side. This venting prevents the buildup of destructive pressure within the barrier, while retaining the required gas separation and electrical conductivity properties. The invention can be applied to systems other than solid oxide fuel cells and includes barriers made of noble metals and non-noble metals.

Abstract: Hydrogen purification membranes, hydrogen purification devices, and fuel processing and fuel cell systems that include hydrogen purification devices. The hydrogen purification membranes include a metal membrane, which is at least substantially comprised of palladium or a palladium alloy. In some embodiments, the membrane contains trace amounts of carbon, silicon, and/or oxygen. In some embodiments, the membranes form part of a hydrogen purification device that includes an enclosure containing a separation assembly, which is adapted to receive a mixed gas stream containing hydrogen gas and to produce a stream that contains pure or at least substantially pure hydrogen gas therefrom. In some embodiments, the membrane(s) and/or purification device forms a portion of a fuel processor, and in some embodiments, the membrane(s) and/or purification device forms a portion of a fuel processing or fuel cell system.

Abstract: A process for converting hydrocarbons and water vapor into hydrogen, carbon monoxide, and carbon dioxide; a fuel cell device; and a process of utilizing the fuel cell to convert chemical energy to electrical energy is described. The fuel cell comprises a metallic and/or mixed conducting anode, a metallic and/or mixed conducting cathode, a proton-conducting ceramic electrolyte between the anode and the cathode, and an external load connecting the anode and the cathode. The fuel cell also includes systems for bringing gaseous hydrocarbon fuels into contact with the anode and for bringing oxygen and water vapor into contact with the cathode. Water vapor in the fuel cell passes through the ceramic electrolyte membrane from the cathode side to the anode side by ambipolar diffusion, called “steam permeation” without conducting current, under the influence of a water vapor concentration gradient.

Abstract: A hydrogen diffusion cell that is used to purify contaminated hydrogen gas. The hydrogen diffusion cell has at least one hydrogen diffusion structure that separates a first area from a second area. Normally, the pressure in the first area is kept higher than the pressure in the second area. This causes a pressure differential that causes hydrogen gas to permeate from the first area to the second area. However, an extreme pressure differential can occur when the second area is at its maximum pressure and the first area is inadvertently vented to ambient pressure. Under this extreme pressure differential hydrogen gas permeates from the second area back into the first area at a maximum reverse flow rate. A flow restrictor is provided that limits the flow of gas exiting the first area to a flow rate no greater than the maximum reverse flow rate.