Abstract: Provided are an exhaust gas treatment catalyst capable of reducing ammonia leakage rate while keeping a sufficient NOx removal efficiency, said catalyst comprising a coating layer and a catalyst base material, wherein said coating layer has a decreased thickness relative to that of a catalyst base material; and an exhaust gas treatment system using the same. In the exhaust gas treatment catalyst for catalytically removing nitrogen oxides from an exhaust gas by using ammonia as a reducing agent and simultaneously decomposing and removing unreacted ammonia, a coating layer comprising platinum supported on titania is formed on a surface of a porous catalyst base material comprising titania and at least one compound selected from oxides of vanadium (V), oxides of tungsten (W) and oxides of molybdenum (Mo).

Abstract: An air pollution control apparatus according to the present invention reduces nitrogen oxides and oxidizes mercury in flue gas 16 discharged from a boiler by an ammonia denitrating catalyst. The air pollution control apparatus includes an economizer bypassing unit 15a that diverts high-temperature combustion gas 11 to a downstream side while bypassing an economizer 15 provided in a gas flue 10a for combustion gas 11 from the boiler, provided with an ammonium-chloride supply unit 101 that supplies powdery ammonium chloride (NH4Cl) to the economizer bypassing unit 15a. The air pollution control apparatus sublimates the ammonium chloride in an atmosphere at a high temperature of the combustion gas 11, and supplies hydrogen chloride and ammonium into the flue gas flue 102.

Abstract: To provide an SO3 reduction catalyst for purifying an exhaust gas capable of efficiently reducing the amount of SO3 that is present in a combustion exhaust gas and is a starting substance of S-containing substances such as acid ammonium sulfate causing deterioration of performance of the catalyst or corrosion of apparatuses disposed downstream of the catalyst, or capable of controlling the generation of SO3 in the catalyst itself; a preparation process of the catalyst; and an exhaust gas purifying method using the catalyst. In the catalyst for purifying a combustion exhaust gas containing nitrogen oxides, 50 wt. % or greater of the amount of Ru and/or Ir to be supported is adjusted to fall within a depth of 150 ?m from the surface layer of a substrate; and the catalyst is prepared by immersing the substrate in a metal colloid solution of Ru and/or Ir to be supported or an aqueous solution containing at least one compound selected from compounds of Ru and/or Ir to be supported.

Abstract: To provide a catalyst for treating exhaust gases containing nitrogen monoxide, carbon monoxide and volatile organic compounds whose oxidation power has been enhanced without increasing the amount of precious metal supported thereon; a method for producing the same; and a method for treating exhaust gases. A catalyst for treating exhaust gases, including coat layers made up of a plurality of layers, an upper layer of which has an active component contained uniformly therein and a lower layer of which has no active component contained therein, can be obtained through the steps of: forming the lower layer by coating the surface of substrate with a slurry of a porous inorganic compound, followed by drying; and forming the upper layer, which is to be the top surface of the catalyst, by coating the surface of the lower layer with a slurry of a porous inorganic compound that has the active component composed of one or more precious metals supported thereon, followed by drying.

Abstract: An object of the present invention is to provide a method for producing a catalyst for treating exhaust gas, enabling a smaller amount of a noble metal to be supported and reducing the production cost thereof. There is provided a method for producing a catalyst for treating an exhaust gas containing carbon monoxide and volatile organic compounds, wherein the method comprises: preparing, as a pH buffer solution, an aqueous metal salt solution in which at least one metal salt is dissolved; reductively-treating the aqueous metal salt solution while keeping the pH constant to prepare a metal colloid solution; and immersing a carrier in the metal colloid solution to support the metal on the carrier. The supported amount of metal may be 0.7 g/L or less per one of the metals.

Abstract: A catalyst for purifying an exhaust gas containing carbon monoxide and volatile organic compounds, which has a coat layer of a carrier composed of a porous inorganic compound, wherein the coat layer is a single layer, the porous inorganic compound has a BET specific surface area of 50 m2/g or greater, and the coat layer has, within a 50 ?m depth from the surface thereof, an active metal having a particle size of 15 nm or less and composed of at least one noble metal.

Abstract: It is intended to provide an exhaust gas treatment system, which allows for VOC removal at lower temperatures and thereby improves the durability of catalysts and suppresses carbon monoxide generation at the final outlet of the system. The present invention provides a treatment system of an exhaust gas containing a nitrogen oxide, carbon monoxide, and a volatile organic compound comprising: an exhaust gas treatment means for removing the nitrogen oxide by reduction with ammonia and partially oxidizing the VOC to CO; and a CO/VOC removal means for oxidizing the CO and partially unreacted VOC, in this order from the upstream flow of the exhaust gas.

Abstract: An object of the present invention is to provide a catalyst for treating exhaust gas adapted not only to remove CO and VOCs based on unsaturated hydrocarbons such as C2H4 but also to accelerate a decomposition reaction of saturated hydrocarbons such as propane and to provide a method for producing such a catalyst for treating exhaust gas. The present invention provides a catalyst for treating an exhaust gas containing carbon monoxide and volatile organic compounds, the catalyst comprising a substrate containing a NOx removal catalyst component and a porous inorganic compound layer containing a noble metal, the layer being applied to the substrate.

Abstract: Provided are a flue gas denitration catalyst having high denitration activity and capable of suppressing a side reaction, that is, oxidation of SO2; and a preparation process of the catalyst. The flue gas denitration catalyst comprises TiO2, WO3 and V2O5. In the surface layer of the catalyst within 200 ?m from the surface thereof, V2O5 is supported on a carrier containing TiO2 and WO3. The supported amounts of V2O5 range from 0.4 to 5 wt. % based on the weight of the surface layer and range from 0.1 to 0.9 wt. % based on the total weight of the catalyst. The V2O5 thus supported has a crystallite size of less than 10 nm as measured by X-ray diffraction. The catalyst can be available by preparing a mixture containing TiO2 and WO3 and having V2O5 supported on the surface of an extruded product of the prepared mixture by a vapor phase method.

Abstract: A catalyst for purifying an exhaust gas containing carbon monoxide and volatile organic compounds, which has a coat layer of a carrier composed of a porous inorganic compound, wherein the coat layer is a single layer, the porous inorganic compound has a BET specific surface area of 50 m2/g or greater, and the coat layer has, within a 50 ?m depth from the surface thereof, an active metal having a particle size of 15 nm or less and composed of at least one noble metal.

Abstract: Provided are a flue gas denitration catalyst having high denitration activity and capable of suppressing a side reaction, that is, oxidation of SO2; and a preparation process of the catalyst. The flue gas denitration catalyst comprises TiO2, WO3 and V2O5. In the surface layer of the catalyst within 200 ?m from the surface thereof, V2O5 is supported on a carrier containing TiO2 and WO3. The supported amounts of V2O5 range from 0.4 to 5 wt. % based on the weight of the surface layer and range from 0.1 to 0.9 wt. % based on the total weight of the catalyst. The V2O5 thus supported has a crystallite size of less than 10 nm as measured by X-ray diffraction. The catalyst can be available by preparing a mixture containing TiO2 and WO3 and having V2O5 supported on the surface of an extruded product of the prepared mixture by a vapor phase method.

Abstract: Provided are a flue gas denitration catalyst having high denitration activity and capable of suppressing a side reaction, that is, oxidation of SO2; and a preparation process of the catalyst. The flue gas denitration catalyst comprises TiO2, WO3 and V2O5. In the surface layer of the catalyst within 200 &mgr;m from the surface thereof, V2O5 is supported on a carrier containing TiO2 and WO3. The supported amounts of V2O5 range from 0.4 to 5 wt. % based on the weight of the surface layer and range from 0.1 to 0.9 wt. % based on the total weight of the catalyst. The V2O5 thus supported has a crystallite size of less than 10 nm as measured by X-ray diffraction. The catalyst can be available by preparing a mixture containing TiO2 and WO3 and having V2O5 supported on the surface of an extruded product of the prepared mixture by a vapor phase method.