摘要:
This is a catalyst and a process for partially hydrogenating polycyclic and monocyclic aromatic hydrocarbons such as benzene, naphthalenes, biphenyls, and alkylbenzenes to produce the corresponding cycloolefins. The catalyst is a hydrogenation catalyst comprising ruthenium and a promoter metal, such as cobalt, on a composite support. It is a process in which the product cycloolefin is produced in high yield and with high selectivity.
摘要:
This invention is a catalyst comprising palladium on a support containing zirconium and a partial combustion process in which the fuel is partially combusted using that catalyst. The choice of catalysts and supports solves a problem dealing with the long term stability of palladium as a partial combustion catalyst. The catalyst structure is stable in operation, has a comparatively low operating temperature, has a low temperature a which oxidation begins, and yet is not susceptible to temperature "runaway". The combustion gas produced by the catalytic process typically is at a temperature below the autocombustive temperature and may be used at that temperature or it may be fed to other combustion stages for further use in a gas turbine, furnace, boiler, or the like.
摘要:
This invention is a graded catalyst comprising palladium and also a partial combustion process in which the fuel is partially combusted using that catalyst. The catalyst utilizes a catalytic support structure suitable for high flow rates of combustible gas mixtures through it. The catalyst is situated on the support so that in the flowing gas stream a leading portion of the support has a higher combustion activity, such as by a higher concentration of catalytic metal, than has the trailing portion. The combination of graded catalyst and support provides a low "light off" temperature for the combustible gas (only a low preheat temperature is needed to cause the combustion reaction to begin) and yet does not cause "hot spots" to occur because of excess activity. The combustion gas produced by the catalytic process may be at a temperature below the adiabatic combustive temperature, may be used at that temperature, or fed to other combustion stages for further use in a gas turbine, furnace, boiler, or the like.
摘要:
This invention is a process for catalytically oxidizing cycloolefins, particularly cyclohexenes, to form a variety of oxygenates. The catalyst used in the process is a covalently bonded iridium-heteropolyanion species. The process uses the catalyst in conjunction with a gaseous oxygen containing gas to form 2-cyclohexen-1-ol and also 2-cyclohexen-1-one.
摘要:
This invention is a graded catalyst comprising palladium and also a partial combustion process in which the fuel is partially combusted using that catalyst. The catalyst utilizes a catalytic support structure suitable for high flow rates of combustible gas mixtures through it. The catalyst is situated on the support so that in the flowing gas stream a leading portion of the support has a higher combustion activity, such as by a higher concentration of catalytic metal, than has the trailing portion. The combination of graded catalyst and support provides a low "light off" temperature for the combustible gas (only a low preheat temperature is needed to cause the combustion reaction to begin) and yet does not cause "hot spots" to occur because of excess activity. The combustion gas produced by the catalytic process may be at a temperature below the adiabatic combustive temperature, may be used at that temperature, or fed to other combustion stages for further use in a gas turbine, furnace, boiler, or the like.
摘要:
This invention is a process for the production of trialkyl acetic acids, particularly of pivalic acid, from branched olefins, particularly isobutene, and carbon monoxide using a solid acid catalyst and optionally with minor amounts of a Lewis acid such as boron trifluoride.
摘要:
This invention is a comparatively high pressure combustion process having a two stages in which a fuel is stepwise combusted using specific catalysts and catalytic structures and, optionally, having a final homogeneous combustion zone. The choice of catalysts and the use of specific structures, including those employing integral heat exchange, results in an overall catalyst structure which is stable due to its comparatively low temperature. The product combustion gas is at a temperature suitable for use in a gas turbine, furnace, boiler, or the like, but has low NO.sub.x content.
摘要:
This invention relates to an electrically-heated catalyst (EHC) and a start-up method of a gas turbine engine for combusting a hydrocarbonaceous fuel/oxygen-containing gas mixture using this electrically-heated catalyst. The catalytic structure is electrically heated to a predetermined temperature prior to start up of the turbine so as to reduce emissions during the start-up of the system. The EHC unit is a stacked or spirally wound layering of flat and corrugated thin metal foils which forms a plurality of axially-extending, longitudinal channels. The channels are preferably coated on one surface with a catalytic material, leaving the other surface free from the reaction to act as a heat sink, making the design an IHE (integral heat exchange) catalytic unit. The preferred embodiment of the EHC has electrodes outside of the fuel/oxygen-containing mixture stream, and uses electrical power having a predetermined voltage in the range of 100 to 200 volts to heat the unit. A method for using the EHC in the start-up of a gas turbine is also disclosed wherein an electrical power is applied to heat the EHC a predetermined temperature prior to the fuel/oxygen-containing mixture being introduced and may be left on for a certain period of time after the introduction of the fuel/oxygen-containing mixture. The EHC may be maintained at the desired predetermined temperature by modulating the applied voltage. The electrical power is terminated when any one of several conditions are met including when the heat of the catalytic reaction is sufficient to maintain the catalyst at its steady-state condition or when a certain period of time has elapsed.
摘要:
The present invention provides aqueous catalyst solutions useful for oxidation of olefins to carbonyl products, comprising a palladium catalyst and a polyoxoacid or polyoxoanion oxidant comprising vanadium. It also provides processes for oxidation of olefins to carbonyl products, comprising contacting olefin with the aqueous catalyst solutions of the present invention. It also provides processes for oxidation of olefins to carbonyl products by dioxygen, comprising contacting olefin with the aqueous catalyst solutions of the present invention, and further comprising contacting dioxygen with the aqueous catalyst solutions. In certain aqueous catalyst solutions and related processes of the present invention, the solution has a hydrogen ion concentration greater than 0.10 mole per liter when essentially all of the oxidant is in its oxidized state. In other aqueous catalyst solution and related processes of the present invention, the solution is essentially free of sulfuric acid and sulfate ions.
摘要:
This invention is an improved catalyst structure and its use in highly exothermic processes like catalytic combustion. This improved catalyst structure employs integral heat exchange in an array of longitudinally disposed adjacent reaction passage-ways or channels, which are either catalyst-coated or catalyst-free, wherein the configuration of the catalyst-coated channels differs from the non-catalyst channels such that, when applied in exothermic reaction processes, such as catalytic combustion, the desired reaction is promoted in the catalytic channels and substantially limited in the non-catalyst channels. The invention further comprises an improved reaction system and process for combustion of a fuel wherein catalytic combustion using a catalyst structure employing integral heat exchange, preferably the improved structures of the invention, affords a partially-combusted, gaseous product which is passed to a homogeneous combustion zone where complete combustion is promoted by means of a flameholder.