Abstract: The present invention is to provide a catalyst for removing nitrogen oxides which is capable of keeping sufficient denitrification performance, i.e., a high removal rate of nitrogen oxides in exhaust gas having a high NO2 content especially under conditions where the ratio of NO2/NO in exhaust gas is 1 or higher, a catalyst molded product therefor, and an exhaust gas treating method. The catalyst is designed for removing nitrogen oxides, which is used to denitrify exhaust gas containing nitrogen oxides having a high NO2 content, which comprises: at least one kind of oxide selected from the group consisting of copper oxides, chromium oxides, and iron oxides as a component for reducing NO2 to NO; and which further comprises: at least one kind of titanium oxide; at least one kind of tungsten oxide; and at least one kind of vanadium oxide as components for reducing NO to N2.

Abstract: In an exhaust gas treatment, the amount of a highly corrosive mercury-halogenating agent to be added is reduced with the mercury-removing efficiency maintained high. A mercury-halogenating agent (40) and ammonia (30) are added to combustion exhaust gas from a boiler, the exhaust gas containing NOx, SOx and mercury. The exhaust gas is brought into contact with a CO/HC oxidation catalyst (50) and is then subjected to reduction denitration (60) in the presence of a solid catalyst. Thereafter, metallic mercury is oxidized to halogenated mercury. Then, the exhaust gas is wet-desulfurized (100) with the alkaline absorbing solution, and the halogenated mercury is removed.

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: The invention provides a discharge gas treatment catalyst which can effectively decreases NOx and SO3 contained in a discharge gas. The discharge gas treatment catalyst, for removing nitrogen oxide and sulfur trioxide from a discharge gas, includes a carrier which is formed of titania-tungsten oxide and which carries ruthenium, and a titania-tungsten oxide-based NOx removal catalyst serving as a substrate which is coated with the carrier. When a discharge gas to which ammonia has been added and which contains SO3 and NOx is brought into contact with the catalyst, decomposition of ammonia is suppressed by ruthenium, and reduction of SO3 and NOx contained in the discharge gas is promoted, whereby SO3 concentration and NOx concentration can be further decreased.

Abstract: Provided is a method of regenerating an exhaust gas treatment catalyst 11 having ash adhered to a surface thereof. The method includes a crushing step S1 in which the exhaust gas treatment catalyst 11 is crushed such that 70 to 95 wt % of the whole exhaust gas treatment catalyst 11 becomes coarse pieces 12 having a size exceeding a threshold size S (any value in a range of 0.105 to 1.0 mm); a separating step S2 in which the fragments obtained by crushing the exhaust gas treatment catalyst 11 are separated into the coarse pieces 12 having a size exceeding threshold size S and fine particles 13 having a size not larger than the threshold size S; a pulverizing step S3 in which the coarse pieces 12 thus separated are pulverized to a fine powder having an average particle diameter of not larger than 0.

Abstract: Provided is a catalyst for treating exhaust gas capable of reducing the amount of a highly corrosive mercury-chlorinating agent to be added while keeping the mercury oxidation efficiency high in an exhaust gas treatment. By the catalyst for treating exhaust gas, nitrogen oxide in the exhaust gas is removed upon contact with ammonia serving as a reducing agent, and mercury is oxidized using a halogen serving as an oxidant. The catalyst includes: TiO2 as a support; an oxide of at least one selected from the group consisting of V, W and Mo, which is supported as an active component on the support; and at least one selected from the group consisting of Bi, P, and compounds containing Bi and/or P, which is supported as a co-catalyst component on the support.

Abstract: An exhaust gas treatment catalyst for removal of one or more pollutants in an exhaust gas, the catalyst comprising: a SO3-reducing catalyst powder which removes the above-described pollutants; and a diluent powder which is not the SO3-reducing catalyst powder nor a catalyst for reactions between exhaust gas components and a reagent, wherein the SO3-reducing catalyst powder is dispersed in the diluent powder.

Abstract: A catalyst for nitrogen oxide removal, which catalytically reduces nitrogen oxides in an exhaust gas in the presence of ammonia, comprises: a first component comprising an oxide of titanium, an oxide of tungsten, and an oxide of vanadium; and a second component comprising an oxide of manganese, or an oxide of manganese and an oxide of copper.

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: A denitrification catalyst regeneration method comprises heat-treating a used denitrification catalyst, then cleaning the denitrification catalyst with an aqueous solution of oxalic acid, and then finish washing the denitrification catalyst with water to regenerate the denitrification catalyst.

Abstract: A denitrification catalyst regeneration method comprises heat-treating a used denitrification catalyst, then cleaning the denitrification catalyst with an aqueous solution of oxalic acid, and then finish washing the denitrification catalyst with water to regenerate the denitrification catalyst.

Abstract: A discharge gas treatment apparatus and method which lower treatment cost and which attain efficient removal of mercury contained in a discharge gas are provided. The discharge gas treatment apparatus, includes a cooling apparatus for controlling the temperature of the discharge gas to a predetermined temperature in accordance with the hydrogen chloride concentration of the discharge gas; an NOx removal catalyst unit for reducing nitrogen oxide contained in the discharge gas and for causing reaction between mercury and hydrogen chloride contained in the discharge gas, the discharge gas having been controlled to the predetermined temperature and having been introduced to the apparatus, with ammonia being added thereto; and a wet-format desulfurization apparatus, disposed on the downstream side with respect to the NOx removal catalyst unit, for removing sulfur oxide and mercury chloride contained in the discharge gas through dissolving sulfur oxide and mercury chloride in a liquid absorbent.

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: The present invention is to provide a catalyst for removing nitrogen oxides which is capable of keeping sufficient denitrification performance, i.e., a high removal rate of nitrogen oxides in exhaust gas having a high NO2 content especially under conditions where the ratio of NO2/NO in exhaust gas is 1 or higher, a catalyst molded product therefor, and an exhaust gas treating method. The catalyst is designed for removing nitrogen oxides, which is used to denitrify exhaust gas containing nitrogen oxides having a high NO2 content, which comprises: at least one kind of oxide selected from the group consisting of copper oxides, chromium oxides, and iron oxides as a component for reducing NO2 to NO; and which further comprises: at least one kind of titanium oxide; at least one kind of tungsten oxide; and at least one kind of vanadium oxide as components for reducing NO to N2.

Abstract: A denitrification catalyst regeneration method comprises heat-treating a used denitrification catalyst, then cleaning the denitrification catalyst with an aqueous solution of oxalic acid, and then finish washing the denitrification catalyst with water to regenerate the denitrification catalyst.

Abstract: The present invention is to provide a catalyst for removing nitrogen oxides which is capable of keeping sufficient denitrification performance, i.e., a high removal rate of nitrogen oxides in exhaust gas having a high NO2 content especially under conditions where the ratio of NO2/NO in exhaust gas is 1 or higher, a catalyst molded product therefor, and an exhaust gas treating method. The catalyst is designed for removing nitrogen oxides, which is used to denitrify exhaust gas containing nitrogen oxides having a high NO2 content, which comprises: at least one kind of oxide selected from the group consisting of copper oxides, chromium oxides, and iron oxides as a component for reducing NO2 to No; and which further comprises: at least one kind of titanium oxide; at least one kind of tungsten oxide; and at least one kind of vanadium oxide as components for reducing NO to N2.

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.