摘要:
A water gas shift catalyst comprising a platinum group metal dispersed on an inorganic oxide support modified with a carbon-containing burn-out additive and a rare earth oxide. A water gas shift catalyst containing alumina, a platinum group metal, and oxides of Pr and Nd are also disclosed.
摘要:
Operating conditions for generating hydrogen by the water-gas shift reaction have been found which reduce the aging of Pt—Re bimetallic water-gas shift catalysts. The process parameters provide a stable operation in residential fuel processors and in hydrogen generators for on-site hydrogen generation.
摘要:
A method for treating cooking fumes to oxidize oxidizeable particulate and gaseous components thereof includes contacting the fumes with a catalytic material containing ceria and alumina each having a BET surface of at least about 10 m.sup.2 /g, for example, ceria and activated alumina in a weight ratio of from about 1.5:1 and 1:1.5 and a BET surface area of from about 25 m.sup.2 /g to 200 m.sup.2 /g. Optionally, a catalytic metal component such as platinum or palladium may be included in the catalytic material. The foodstuffs cooking fumes are contacted with the catalyst composition (22 or 40) at a temperature of 200.degree. C. to 600.degree. C. to promote the oxidation of both particulate (atomized) animal and/or vegetable oils and fats and oxidizeable gas phase components of the fumes. Optionally, a separate, supplemental gas phase oxidation catalyst (42) may be used in conjunction with and downstream of the above-described catalyst (40) to provide a two-catalyst system for treating cooking fumes.
摘要:
A catalyst composition containing one or more binary oxides of palladium and rare earth metal such as Ce, La, Nd, Pr and/or Sm. The catalyst composition is used for the catalytic combustion of gaseous combustion mixtures of oxygen and carbonaceous fuels such as methane, e.g., a natural gas/air combustion mixture. Specific preferred binary oxides may be, for example, M.sub.2 O.sub.3.PdO (e.g., La.sub.2 O.sub.3.PdO) or 2M.sub.2 O.sub.3.PdO, wherein in each case M is La, Nd or Sm. A process of combusting gaseous carbonaceous fuels includes contacting a catalyst as described above under combustion conditions, e.g., 925.degree. C. to 1650.degree. C. and 1 to 20 atmospheres pressure, to carry out sustained combustion of the combustion mixture, including catalytically supported thermal combustion. Regeneration of over-temperatured M.sub.2 O.sub.3.PdO catalyst is also provided for.
摘要:
Oxidation catalyst compositions include a catalytic material containing ceria and alumina each having a surface area of at least about 10 m.sup.2 /g, for example, ceria and activated alumina in a weight ratio of from about 1.5:1 to 1:1.5. Optionally, platinum may be included in the catalytic material in amounts which are sufficient to promote gas phase oxidation of CO and HC but which are limited to preclude excessive oxidation of SO.sub.2 to SO.sub.3. Alternatively, palladium in any desired amount may be included in the catalytic material. The catalyst compositions have utility as oxidation catalysts for pollution abatement of exhausts contianing unburned fuel or oil. For example, the catalyst compositions may be used in a method to treat diesel engine exhaust by contacting the hot exhaust with the catalyst composition to promote the oxidation of the volatile organic fraction component of particulates in the exhaust.
摘要:
A method for operating a palladium oxide containing catalytic combustor useful, e.g., for powering a gas turbine, wherein the palladium oxide is supported on a metal oxide such as alumina, ceria, titania or tantalum oxide. The method involves maintaining control of the temperature within the combustor in such a manner as to insure the presence of palladium oxide. By maintaining the temperature below about 800.degree. C. decomposition of palladium oxide into metallic palladium is avoided and high catalytic activity is retained. Regeneration of catalyst following inactivation resulting from an over-temperature is accomplished by using a heat soak in a temperature range which varies depending on the metal oxide used to support the palladium oxide.
摘要:
Platinum-rhodium and platinum-palladium-rhodium gauzes bearing a high surface area coating (in excess of 50 cm.sup.2 /g) of platinum ease initiation of ammonia oxidation.
摘要:
A hydrocarbon gas such as methane and LPG is desulfurized in the presence of oxygen and an oxidation catalyst to convert sulfur compounds in the gas to sulfur oxides. The sulfur oxides are then trapped downstream of the oxidation by an adsorbent. The amount of oxygen added to the hydrocarbon gas to promote oxidation is such that the sulfur compounds are selectively oxidized and the oxidation of the hydrocarbon gas is minimized to reduce hydrogen formation.
摘要:
Provided is a method of generating a hydrogen-rich reformate from a hydrocarbon feed stream comprising olefins and alkanes (e.g., LPG). An inlet gas stream containing the hydrocarbon feed stream and an oxygen containing gas stream, is preheated to a temperature of from 180 to 300° C. The preheated inlet gas stream is then contacted with a sulfur tolerant partial oxidation catalyst to form a pre-reformed gas stream, which is preferably maintained below about 400° C. The pre-reformed gas stream is then subjected to a reforming process to form the hydrogen-rich reformate.