854 results about "Hydrogen flow" patented technology

A method to promote the activity of a catalyst for dehydrogenation of propane to propylene is as follows: (1) an inorganic oxide bonding agent, a promoter and an acid solvent are added into a heat-resistant oxide; then after the oxide bonding agent, the promoter, the acid solvent and the oxide are kneaded evenly, the oxide is molded by rolling or band-extruding; (2) the catalyst carrier prepared is dried for 2 to 10 hours under the temperature of 60 centigrade degrees, and calcined under the temperature of 400 to 800 degrees; (3) the calcined carrier is immersed in a rare earth metal water solution under the temperature of 60 to 100 centigrade degrees for 2 to 10 hours; (4) the catalyst carrier modified by the rare earth is immersed in a water solution comprising platinum metal elementsand the fourteenth metal elements under the temperature of 400 to 600 centigrade degrees for 2 to 10 hours, and then the carrier is filtered, washed with distilled water, dried under the temperature of 60 to 180 centigrade degrees for 2 to 10 hours, and calcined under the temperature of 400 to 600 centigrade degrees for 2 to 10 hours; (5) the catalyst prepared is activated in the air under the temperature of 400 to 600 centigrade degrees for 3 to 10 hours, and reduced in a hydrogen flow under the temperature of 400 to 600 centigrade degrees for 2 to 10 hours; the reduced catalyst is used for catalytic reaction for dehydrogenation of propane to propylene.

Between adjacent MEA's is a bipolar plate assembly having a first sub-plate with a flow channel which is open to the anode side of the one of the MEA's. A second sub-plate has a flow channel which is open to the cathode side of the adjacent MEA. The sub-plates are nested together to form a coolant flow channel between the sub-plates. The coolant flow path has a height dimension wherein the distance between the adjacent MEA's is substantially unaffected by the height dimension of the coolant flow path. A method of manufacturing a bi-polar plate assembly includes forming a closed coolant flow channel between the sub-plates by nesting the sub-plates together. A method of operating a fuel cell includes passing the coolant through a flow path having a height dimension which is substantially aligned with the height dimension of the hydrogen flow path, the oxygen flow path, or both.

This invention relates to a start-up method for oxidation-state hydrocracking catalyst used in oil refinery process. The method comprises: loading the oxidation-state hydrocracking catalyst into a reactor, introducing nitrogen to replace air in the reactor and pipelines, pressurizing to meet the pressure requirement of hydrocracking, switching to hydrogen after nitrogen flow is stable, raising the temperature of the catalyst bed to meet the temperature requirement of catalyst reduction after hydrogen flow is stable, keeping the temperature, adjusting the temperature of the catalyst bed to meet the temperature requirement of hydrocracking, adjusting hydrogen flux to meet the flux requirement of hydrocracking, and introducing hydrocarbon reactants. The method does not need pre-sulfurization of the catalyst with additional sulfurization agent, thus can avoid the problems caused by pre-sulfurization, and partially reduced catalyst has higher hydrocracking activity.

An electrochemical cell system includes a hydrogen electrode; an oxygen electrode; a membrane disposed between the hydrogen electrode and the oxygen electrode; and a compartmentalized storage tank. The compartmentalized storage tank has a first fluid storage section and a second fluid storage section separated by a movable divider. The compartmentalized storage tank is in fluid communication with the electrochemical cell. Further, an electrochemical cell includes a hydrogen electrode; an oxygen electrode; an electrolyte membrane disposed between and in intimate contact with the hydrogen electrode and said oxygen electrode; an oxygen flow field disposed adjacent to and in intimate contact with the oxygen electrode; a hydrogen flow field disposed adjacent to and in intimate contact with the hydrogen electrode; a water flow field disposed in fluid communication with the oxygen flow field; and a media divider disposed between the oxygen flow field and the water flow field.

A diagnostic method of detecting component failures in a fuel cell anode subsystem involves estimating fuel flow through injectors and comparing the estimated flow with a model based upon the system parameters. An observer based model is used to determine a residual value, the difference between the hydrogen input and the hydrogen consumed, and the residual is compared with a threshold range. In alternative embodiments, the stack current and the state of the valves are used to calculate the required hydrogen flow through the injectors and the duty cycle of an injector is compared to a tolerance range.

A hydrogen fuel system comprises an open gas circuit that includes a source of hydrogen. The hydrogen fuel system also includes a compressor that forces a flow of hydrogen from the source of hydrogen through the open gas circuit, and a hydrogen storage vessel comprising an inlet and an outlet. The hydrogen fuel system may also include a hydrogen storage bed being disposed within the hydrogen storage vessel between the inlet and the outlet, the hydrogen storage vessel being adapted to form a portion of the open gas circuit so that the hydrogen storage bed is cooled by convection while hydrogen flows through the open gas circuit.

A silicon wafer used in manufacturing crystalline GaN for light emitting diodes (LEDs) includes a silicon substrate, a buffer layer of aluminum nitride (AlN) and an upper layer of GaN. The silicon wafer has a diameter of at least 200 millimeters and an Si(111)1×1 surface. The AlN buffer layer overlies the Si(111) surface. The GaN upper layer is disposed above the buffer layer. Across the entire wafer substantially no aluminum atoms of the AlN are present in a bottom most plane of atoms of the AlN, and across the entire wafer substantially only nitrogen atoms of the AlN are present in the bottom most plane of atoms of the AlN. A method of making the AlN buffer layer includes preflowing a first amount of ammonia equaling less than 0.01% by volume of hydrogen flowing through a chamber before flowing trimethylaluminum and then a subsequent amount of ammonia through the chamber.

A multiplicity of silicon wafers polished at least on their front sides are provided and successively coated individually in an epitaxy reactor by a procedure whereby one of the wafers is placed on a susceptor in the epitaxy reactor, is pretreated under a hydrogen atmosphere at a first hydrogen flow rate, and with addition of an etching medium to the hydrogen atmosphere at a reduced hydrogen flow rate in a second step, is subsequently coated epitaxially on its polished front side, and removed from the reactor. An etching treatment of the susceptor follows a specific number of epitaxial coatings. Silicon wafers produced thereby have a global flatness value GBIR of 0.07-0.3 μm relative to an edge exclusion of 2 mm.

The invention provides a device for testing fuel cell stacks, which comprises a working gas supply system connected with a fuel cell, and a control system. The working gas supply system comprises a hydrogen pipe and an air pipe; wherein a first flow control unit for detecting and controlling the flow of hydrogen is arranged on the hydrogen pipe; a second flow control unit for detecting and controlling the flow of air is arranged on the air pipe; and the control system is electrically connected with the first flow control unit and the second flow control unit respectively, and is used for collecting detecting signals sent by the first flow control unit and the second flow control unit so as to record the hydrogen flow in the hydrogen pipe and the air glow in the air pipe. the device has the advantages of effectively solves the problem that the correlation data of hydrogen and air flow and fuel cell performance parameters under the loading condition of fuel cell stacks cannot be detected in the prior art.