Abstract:
A catalyst-testing apparatus includes a heater, a U-shaped reactor, a gas flow controller, a liquid flow controller, two pressure gauges, a separator and a chromatograph. In use, under control of the gas flow controller, natural gas and air are directed to the U-shaped reactor. Under control of the liquid flow controller, pure water is directed to the U-shaped reactor. The pure water travels down the wall of the U-shaped reactor. The pure water is heated and turned into steam in a front section of the U-shaped reactor. Together with the natural gas and the air, the steam is directed to a catalyst zone in the U-shaped reactor for reaction. With the chromatograph, volumes and compositions of resultant gases are analyzed. Thus, the stability of the performance of the catalyst is tested, and the performance of the catalyst for producing hydrogen by is revealed.
Abstract:
A catalyst-testing apparatus includes a heater, a U-shaped reactor, a gas flow controller, a liquid flow controller, two pressure gauges, a separator and a chromatograph. In use, under control of the gas flow controller, natural gas and air are directed to the U-shaped reactor. Under control of the liquid flow controller, pure water is directed to the U-shaped reactor. The pure water travels down the wall of the U-shaped reactor. The pure water is heated and turned into steam in a front section of the U-shaped reactor. Together with the natural gas and the air, the steam is directed to a catalyst zone in the U-shaped reactor for reaction. With the chromatograph, volumes and compositions of resultant gases are analyzed. Thus, the stability of the performance of the catalyst is tested, and the performance of the catalyst for producing hydrogen by is revealed.
Abstract:
A fuel reforming catalyst is fabricated. The catalyst is used in solid oxide fuel cell. By using the catalyst, the hydrogen generation is enhanced with a great reforming ratio. In addition, the catalyst is coking-resistant and will not be broken into powder after a long time of use.
Abstract:
A fuel reforming catalyst is fabricated. The catalyst is used in solid oxide fuel cell. By using the catalyst, the hydrogen generation is enhanced with a great reforming ratio. In addition, the catalyst is coking-resistant and will not be broken into powder after a long time of use.
Abstract:
This invention relates to the preparations of noble metal catalysts, i.e., platinum and platinum alloys, on suitable supports with nanonetwork structures and high catalytic efficiencies. A compact structure of a monolayer or a few layers is formed by self-assembly of organic polymer, e.g., polystyrene (PS), nanospheres or inorganic, i.e., silicon dioxide (SiO2), nanospheres on a support surface. In the void spaces of such a compact arrangement, catalyst is formed by filling with catalyst metal ion-containing aqueous solution and reduced by chemical reduction, or formed by vacuum sputtering. When using organic polymer nanospheres as the starting or structure-directing material, the polymer particles are removed by burning at a high temperature and the catalyst having a nanonetwork structure is obtained. In the case of using silicon dioxide nanospheres as the starting material, silicon dioxide particles are dissolved with hydrofluoric acid solution and evaporated away leading to formation of a similar nanonetwork structure made of catalyst. The catalysts prepared by these methods possess characteristics of robust in structure, uniform in hole size and high in catalytic surface area. Their main applications include uses as catalysts in direct methanol and proton exchange membrane fuel cells, as well as in chemical reactors, fuel reformers, catalytic converters, etc.
Abstract:
This invention relates to the preparations of noble metal catalysts, i.e., platinum and platinum alloys, on suitable supports with nanonetwork structures and high catalytic efficiencies. A compact structure of a monolayer or a few layers is formed by self-assembly of organic polymer, e.g., polystyrene (PS), nanospheres or inorganic, i.e., silicon dioxide (SiO2), nanospheres on a support surface. In the void spaces of such a compact arrangement, catalyst is formed by filling with catalyst metal ion-containing aqueous solution and reduced by chemical reduction, or formed by vacuum sputtering. When using organic polymer nanospheres as the starting or structure-directing material, the polymer particles are removed by burning at a high temperature and the catalyst having a nanonetwork structure is obtained. In the case of using silicon dioxide nanospheres as the starting material, silicon dioxide particles are dissolved with hydrofluoric acid solution and evaporated away leading to formation of a similar nanonetwork structure made of catalyst. The catalysts prepared by these methods possess characteristics of robust in structure, uniform in hole size and high in catalytic surface area. Their main applications include uses as catalysts in direct methanol and proton exchange membrane fuel cells, as well as in chemical reactors, fuel reformers, catalytic converters, etc.
Abstract:
A simple fuel cell-type electrochemical sensor for sensing the concentration of a specific fuel, e.g., methanol, ethanol, formic acid, sodium borohydride, etc., prepared in an aqueous solution is developed. The sensor is mainly composed of a membrane electrode assembly (MEA), which is made by hot pressing a piece of electro catalytic anode and a piece of electro catalytic cathode on each side of a proton exchange membrane (PEM), such as Nafion® 117. It is uniquely designed to have an anode size much smaller than that of the cathode and utilizes ambient air as an oxidant. The innovative approach is to ensure the fuel diffused to the anode/membrane interface can be totally reacted so as to eliminate the interferences of fuel crossover and enhance output signal. Thus, the measured sensor current reflects the concentration of diffusion-limited fuel at the membrane/electrode interface, which is proportional to fuel concentration in the bulk. It can be easily operated in a passive mode as well as in an active mode with aqueous fuel solution under a stagnant or a flowing condition. The applications include uses in fuel cell systems, such as direct methanol fuel cell systems, for sensing and monitoring fuel concentration in an aqueous solution.