Abstract: A process for generating a high-hydrogen, low-carbon monoxide gas comprises generating a product gas in a gas generating device. The product gas contains hydrogen and carbon monoxide that are generated from catalytic water vapor reforming of a water/fuel mixture and/or from partial oxidation of an oxygen/fuel mixture. In a gas purification stage, the carbon monoxide fraction in the product gas is reduced by selective CO oxidation on an oxidation catalyst. During a starting phase, oxygen is admixed to the supplied fuel and the flow direction is reversed such that the flow first takes place through the gas purification stage and only then through the gas generating device.

Abstract: A device having a plurality of chambers for carrying out a solid-catalyzed reaction includes a common evaporation unit for evaporating liquid starting materials. The evaporation unit is in thermally conductive contact with a plurality of chambers. An area of the evaporation unit in which the evaporation substantially takes place is at least partially surrounded by the plurality of chambers.

Abstract: A methanol reforming catalyst containing passivated copper and zinc oxide and/or alumina can be prepared by (1) precipitating or spray-drying a mixture of catalyst precursor components dissolved or suspended in a diluent in order to form a solid catalyst precursor in the form of powder or granules, (2) calcining and reducing the solid catalyst precursor obtained in stage (1), (3) passivating the reduced catalyst precursor obtained in stage (2) and (4) shaping the passivated catalyst precursor obtained in stage (3) to form the catalyst. A reduction in the volume shrinkage and an increase in the mechanical hardness during operation of the methanol reforming catalyst are achieved by the preparation process.

Abstract: For carrying out a heterogeneously catalyzed reaction, such as the generation of hydrogen from hydrocarbons or alcohol, a reaction mixture comprising a hydrocarbon and water is supplied to a catalyst, which is produced by pressing at least one catalyst powder into a layer. Instead of a metallic housing, stacked layers are sealed by an edge seal, introduced into the layer or applied on the layer.

Abstract: A gas generating system for a fuel cell system as well as to a method of operating same. In order to provide hydrogen-containing combustible gas as rapidly as possible and to reduce the exhaust gas emissions, for the start of the operation of the gas generating system, at least one catalytic burner is started and the generated heat is used for evaporating a combustion agent and/or water and for the heating-up of an additionally connected partial reforming unit or partial oxidation stage in order to generate a hydrogen-containing gas for the fuel cell unit by reforming or partial oxidation.

Abstract: A fuel cell system includes a polymer electrolyte membrane fuel cell unit having a cooling circuit and an evaporator having at least one evaporation chamber for evaporation of a medium in the fuel cell system and at least one heat-transfer chamber which thermally communicates with the evaporation chamber. The heat-transfer chamber is a part of the cooling circuit of the fuel cell unit.

Abstract: An arrangement for generating a hydrogen-containing gas from a hydrocarbon-containing medium includes a multi-stage reforming unit that is connected to a multi-stage carbon monoxide removal unit by a heat-conducting separating medium. The stages of the reforming unit, in an ascending order relative to the gas flow direction in the reforming unit, are in a thermal contact with stages of the carbon monoxide removal unit, in a descending order relative to the gas flow direction in the carbon monoxide removal unit.

Abstract: In a method for improving cold starting of a catalytically active component in gas generation systems for a mobile fuel cell system, a temporary store is arranged directly in the starting-material gas stream. During cold starting, the temporary store stores gaseous constituents from the gaseous starting material, which constituents cause problems when starting, and releases such constituents (which have been stored during the cold-start phase) again as a result of the heating which takes place as operation of the system continues.

Abstract: To carry out a heterogeneously catalysed reaction, a reaction mixture comprising hydrocarbon and water is fed onto a catalyst that is produced by compressing at least one catalyst powder into a highly compressed layer which forms a shaped body. The reaction mixture is pressed through the catalyst layer with a pressure drop.

Abstract: A device for evaporating liquids includes a porous, thermally conductive evaporation body, which contains a catalyst material on one surface, while the evaporation body is gas-impermeable on the opposite surface. Liquid which is to be evaporated and, if appropriate an additional fuel, can be fed to the evaporation body. The heat of evaporation required is provided by an exothermic reaction of the liquid or with a gaseous oxidizing agent at the catalyst material.

Abstract: A fuel cell system includes a fuel cell with a cathode space and an anode space that are separated by a polymer electrolyte membrane. The cathode space is supplied with an oxygen-containing gas, and the anode space is supplied with a hydrogen-containing gas. A gas-generation device is provided in which a hydrogen-rich reformate containing carbon monoxide, is produced from a fuel with the aid of steam reforming and/or partial oxidation. A gas-cleaning stage selectively oxidizes the carbon monoxide in the reformate on a suitable catalyst while oxygen is added; and a heat exchanger which is arranged in the gas-cleaning stage, has a cooling medium flowing through it and serves to dissipate thermal energy. According to the invention, to dissipate the thermal energy, the anode off-gas and/or cathode off-gas emerging from the fuel cell and/or a starting-material gas which is present in the fuel cell system flows through the heat exchanger.

Abstract: In a process for operating a fuel cell system with a water balance, a hydrogen-containing medium or a mixture of mediums is reformed in a reforming reactor with a water requirement, by adding water to a hydrogen rich reformate. The reformate is fed to an anode region of a fuel cell and reacts with oxygen from a cathode region of the fuel cell, forming water in the fuel cell. The the water required for the reforming reaction and/or the water balance of the fuel cell system is coupled directly to the oxidation rate of the partial combustion of the hydrogen-containing medium or the mixture of mediums in an oxidizing unit upstream of the reforming reactor.

Abstract: An apparatus for producing hydrogen from hydrocarbons or alcohol, particularly methanol, by feeding a reaction mixture comprising a hydrocarbon or alcohol and water onto a catalyst. The catalyst is formed by compressing at least one catalyst powder into a compressed layer to form a shaped body. The reaction mixture flows under pressure through the catalyst layer while the pressure drops. Furthermore, the apparatus is suitable for a use in a hydrogen shift phases for reducing carbon monoxide, in carbon monoxide oxidizers and catalytic burners. A process for producing the catalyst is also disclosed.

Abstract: A method for periodically reactivating copper-containing catalyst material includes applying an oxygen-containing gas stream to the catalyst material for reactivation purposes. When the reactor is in the warm operating state, the application of the oxygen-containing gas stream to the catalyst material is interrupted when the monitored temperature of the catalyst material exceeds a maximum level which is a predeterminable tolerance level above a predetermined operating temperature. In cold-start phases, initially a mixture of a fuel and an oxygen-containing gas stream is fed to the catalyst material, until the monitored temperature of the catalyst material exceeds a predeterminable switch-over level, after which only the oxygen-containing gas stream is supplied. To keep the reactor warm after operation has ended, the reactivation can be activated each time the temperature falls below a further threshold level.

Abstract: A gas generating system for a fuel cell system as well as to a method of operating same. In order to provide hydrogen-containing combustible gas as rapidly as possible and to reduce the exhaust gas emissions, for the start of the operation of the gas generating system, at least one catalytic burner is started and the generated heat is used for evaporating a combustion agent and/or water and for the heating-up of an additionally connected partial reforming unit or partial oxidation stage in order to generate a hydrogen-containing gas for the fuel cell unit by reforming or partial oxidation.

Abstract: A process for manufacturing a catalyst body for generating hydrogen having at least one thin, large-surface catalyst layer, through which the reaction mixture can be passed includes steps of pressing a copper powder (particularly dendritic copper) to form a thin and highly compressed layer which forms a formed body, sintering, the formed body in a reducing atmosphere so that a net-type carrier structure made of copper is formed, and activating a surface layer of the formed body.

Abstract: A process for operating a methanol reforming system in which, in the reforming reaction operation, methanol is reformed in a methanol reforming reactor using a methanol reforming catalyst. The reforming reaction operation is interrupted periodically for catalyst reactivation phases during which the methanol reforming catalyst whose catalytic activity decreases in the reforming reaction operation is treated in an activity-regenerating manner. The process may be used in fuel-cell-driven motor vehicles for generating hydrogen for the fuel cells from methanol carried along in the liquid state.

Abstract: A reformation reactor, especially suitable for the reformation of methanol, includes a reaction zone in which a reformation catalyst is located and to which a gas mixture to be reformed can be supplied. The reactor includes an evaporator body that adjoins the reaction zone in a flush manner. The evaporator body has a porous, heat-conducting structure for providing the gas mixture to be reformed by mixing and evaporating the gas mixture components supplied to it and for two-dimensionally distributed supply of the gas mixture thus prepared and into the reaction zone. A starting phase can be provided for the operation of the reactor, in which the evaporator body is wetted by a fuel liquid film and, following the addition of oxygen, a flammable mixture results in the reaction zone that is catalytically oxidized. The evaporator body can be heated to operating temperature by the resultant combustion heat, after which a switch can be made to continuous operation of the reformation reactor.

Abstract: A fuel cell system for a motor vehicle, with at least one fuel cell and with a gas generation system, has at least one device for cleaning the air that is taken in. The device is arranged in an area in front of the cathode chamber of at least one fuel cell and/or in an area in front of a gas generation system, and contains at least one element for adsorption of ions and/or hydrocarbons.

Abstract: In a method and apparatus for producing a hydrogenous gas stream for a fuel cell system, the share of CO contained in the gas stream, is reduced by providing one or more selective oxidation stages which preferably are thermally coupled to a reformer for the reforming of hydrocarbons, or to a heat exchanger. In order to supply the fuel cell system, as quickly as possible, with a hydrogenous gas stream having a low share of CO, so that it can be placed in operation at the temperature of the surrounding environment, one or more additional, thermally decoupled, selective oxidation stages is series-connected to the existing selective oxidation stages at the beginning or end of the series, or at intermediate points.