Provided are a structured catalyst for CO shift or reverse shift that can realize a long life time by suppressing the decline in function, a method for producing the same, a CO shift or reverse shift reactor, a method for producing carbon dioxide and hydrogen, and a method for producing carbon monoxide and water. The structured catalyst for CO shift or reverse shift (1) includes a support (10) of a porous structure composed of a zeolite-type compound, and at least one CO shift or reverse shift catalytic substance (20) present in the support (10), the support (10) has channels (11) connecting with each other, and the CO shift or reverse shift catalytic substance (20) is present at least in the channels (11) of the support (10).

Provided are a structured catalyst for CO shift or reverse shift that can realize a long life time by suppressing the decline in function, a method for producing the same, a CO shift or reverse shift reactor, a method for producing carbon dioxide and hydrogen, and a method for producing carbon monoxide and water. The structured catalyst for CO shift or reverse shift (1) includes a support (10) of a porous structure composed of a zeolite-type compound, and at least one CO shift or reverse shift catalytic substance (20) present in the support (10), the support (10) has channels (11) connecting with each other, and the CO shift or reverse shift catalytic substance (20) is present at least in the channels (11) of the support (10).

A catalyst composition comprising a mixture of (a) a zeolite compound in an amount of from 10% to 60% by weight, wherein the zeolite compound comprises cations selected from Fe.sup.2+, Fe.sup.3+, Cu.sup.+, Cu.sup.2+ or mixtures thereof, and (b) a ceria/zirconia/alumina composite oxide, wherein the alumina content in said composite oxide is in the range of 20 to 80% by weight, in particular of 40 to 60% by weight,
a catalyst comprising such catalyst composition and its use for exhaust gas after-treatment of diesel and lean burn engines.

According to one or more embodiments described, a zeolite supported catalyst may be synthesized by a process that includes combining a colloidal mixture with a metal oxide support material to form a support precursor material, processing the support precursor material to form a support material, and impregnating the support material with one or more metals to form the zeolite supported catalyst. The colloidal mixture may include nano-sized zeolite crystals, and the nano-sized zeolite crystals may have an average size of less than 100 nm.

The invention includes an additive for maximizing production of olefins. The additive comprises a ZSM-5 molecular sieve, at least one inorganic oxide, and phosphorus oxide. The ZSM-5 molecular sieve has iron in the framework, and the additive comprises at least 0.5 weight percent iron, as measured as iron oxide, in the molecular sieve framework. The additive is useful for maximizing production of olefins in a FCC process.

The invention includes an additive for maximizing production of olefins. The additive comprises a ZSM-5 molecular sieve, at least one inorganic oxide, and phosphorus oxide. The ZSM-5 molecular sieve has iron in the framework, and the additive comprises at least 0.5 weight percent iron, as measured as iron oxide, in the molecular sieve framework. The additive is useful for maximizing production of olefins in a FCC process.

In an exhaust gas purification system provided with a denitration catalyst layer, a reducing agent oxidation catalyst layer is installed together; a reducing agent and air are supplied into the reducing agent oxidation catalyst layer at the time of catalyst regeneration of the denitration catalyst layer; a high-temperature oxidation reaction gas is produced by a reaction heat generated by an oxidation reaction of the reducing agent and the air in this reducing agent oxidation catalyst layer; and this high-temperature oxidation reaction gas is introduced into the denitration catalyst layer to heat the denitration catalyst, thereby recovering a denitration performance of the catalyst.

In an exhaust gas purification system provided with a denitration catalyst layer, a reducing agent oxidation catalyst layer is installed together; a reducing agent and air are supplied into the reducing agent oxidation catalyst layer at the time of catalyst regeneration of the denitration catalyst layer; a high-temperature oxidation reaction gas is produced by a reaction heat generated by an oxidation reaction of the reducing agent and the air in this reducing agent oxidation catalyst layer; and this high-temperature oxidation reaction gas is introduced into the denitration catalyst layer to heat the denitration catalyst, thereby recovering a denitration performance of the catalyst.

Disclosed are a hydrocarbon adsorption and desorption complex showing hydrocarbon adsorption and oxidation performance by controlling the cation ratio in zeolite, and a preparation method therefor. The hydrocarbon adsorption and desorption complex controls a cation ratio to exhibit the excellent hydrocarbon adsorption ability and oxidation performance even at a temperature lower than the catalyst activation temperature, and increases hydrothermal stability of the hydrocarbon adsorption and desorption complex through hydrothermal treatment to exhibit the excellent hydrocarbon adsorption and desorption performance even in a situation where water is present at a high temperature.

Provided are zeolite catalysts that allow reactions to proceed at temperatures as low as possible when lower olefins are produced from hydrocarbon feedstocks with low boiling points such as light naphtha, make it possible to make propylene yield higher than ethylene yield in the production of lower olefins, and have long lifetime. The zeolite catalysts are used in the production of lower olefins from hydrocarbon feedstocks with low boiling points such as light naphtha. The zeolite catalysts are MFI-type crystalline aluminosilicates containing iron atoms and have molar ratios of iron atoms to total moles of iron atoms and aluminum atoms in the range from 0.4 to 0.7. The use of the zeolite catalysts make it possible to increase propylene yield, to lower reaction temperatures, and to extend catalyst lifetime.