Abstract: A separation and recovery method that enables titanium and tungsten to be separated and recovered from a used DeNOx catalyst in high yield. Specifically, a method of separating and recovering metal elements that includes a first heating step of heating a DeNOx catalyst containing titanium, tungsten, vanadium and iron in a chlorine atmosphere, thereby removing the vanadium and the iron from the DeNOx catalyst, and a second heating step, performed after the first heating step, of heating the DeNOx catalyst in a chlorine atmosphere while the catalyst is exposed to a gas of a hydrocarbon compound (excluding CH4) or an oxygen-containing carbon compound, thereby volatilizing the tungsten and the titanium from the DeNOx catalyst, and recovering the tungsten and the titanium from the DeNOx 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: The present invention provides a method for removing mercury in exhaust gas, in which mercury in exhaust gas discharged from combustion equipment is removed, characterized by including a mercury oxidation process in which mercury in the exhaust gas is converted to mercury chloride in the presence of a catalyst; a contact process in which the exhaust gas is brought into contact with an absorbing solution in a scrubber to absorb and remove mercury components from the exhaust gas; and a control process in which blowing of air or addition of an oxidizing agent into the scrubber is accomplished, and the amount of blown air or the added amount of oxidizing agent is regulated to control the oxidation-reduction potential of the absorbing agent, and a system for removing mercury in exhaust gas. According to the mercury removing method in accordance with the present invention, a phenomenon that mercury chloride is reduced into metallic mercury by SO2 etc.

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 separation and recovery method that enables titanium and tungsten to be separated and recovered from a used DeNOx catalyst in high yield. Specifically, a method of separating and recovering metal elements that includes a first heating step of heating a DeNOx catalyst containing titanium, tungsten, vanadium and iron in a chlorine atmosphere, thereby removing the vanadium and the iron from the DeNOx catalyst, and a second heating step, performed after the first heating step, of heating the DeNOx catalyst in a chlorine atmosphere while the catalyst is exposed to a gas of a hydrocarbon compound (excluding CH4) or an oxygen-containing carbon compound, thereby volatilizing the tungsten and the titanium from the DeNOx catalyst, and recovering the tungsten and the titanium from the DeNOx catalyst.

Abstract: 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 provides compositions, systems, and methods for achieving high efficiencies of nitrogen oxide (NOx) removal from exhaust gases while minimizing ammonia slip and sulfur dioxide oxidation. In one embodiment, a method of removing nitrogen oxides from an exhaust gas comprises providing a first catalyst layer, adding an ammonia-containing compound to the exhaust gas upstream of the first catalyst layer in excess of the stoichiometric equivalent of the nitrogen oxides in the exhaust gas, flowing the exhaust gas through the first catalyst layer, selectively catalytically decomposing ammonia in excess of the stoichiometric reaction equivalent of the nitrogen oxides in the exhaust gas, and catalytically reducing the nitrogen oxides by reaction with ammonia not selectively catalytically decomposed.

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: The present invention provides compositions, systems, and methods for achieving high efficiencies of nitrogen oxide (NOx) removal from exhaust gases while minimizing ammonia slip and sulfur dioxide oxidation. In one embodiment, a method of removing nitrogen oxides from an exhaust gas comprises providing a first catalyst layer, adding an ammonia-containing compound to the exhaust gas upstream of the first catalyst layer in excess of the stoichiometric equivalent of the nitrogen oxides in the exhaust gas, flowing the exhaust gas through the first catalyst layer, selectively catalytically decomposing ammonia in excess of the stoichiometric reaction equivalent of the nitrogen oxides in the exhaust gas, and catalytically reducing the nitrogen oxides by reaction with ammonia not selectively catalytically decomposed.

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: The present invention provides compositions, systems, and methods for achieving high efficiencies of nitrogen oxide (NOx) removal from exhaust gases while minimizing ammonia slip and sulfur dioxide oxidation. In one embodiment, a method of removing nitrogen oxides from an exhaust gas comprises providing a first catalyst layer, adding an ammonia-containing compound to the exhaust gas upstream of the first catalyst layer in excess of the stoichiometric equivalent of the nitrogen oxides in the exhaust gas, flowing the exhaust gas through the first catalyst layer, selectively catalytically decomposing ammonia in excess of the stoichiometric reaction equivalent of the nitrogen oxides in the exhaust gas, and catalytically reducing the nitrogen oxides by reaction with ammonia not selectively catalytically decomposed.

Abstract: A COS treatment apparatus for a gasified gas includes an O2 removal catalyst and a COS conversion catalyst located on the downstream side of a gasified gas flow with respect to the O2 removal catalyst. Also, a COS treatment apparatus includes a TiO2 catalyst that carries Cr2O3 or NiO. Further, a COS treatment method includes a first step in which O2 is removed by the reaction with H2S and CO, and a second step in which COS is converted to H2S.

Abstract: The present invention provides compositions, systems, and methods for achieving high efficiencies of nitrogen oxide (NOx) removal from exhaust gases while minimizing ammonia slip and sulfur dioxide oxidation. In one embodiment, a method of removing nitrogen oxides from an exhaust gas comprises providing a first catalyst layer, adding an ammonia-containing compound to the exhaust gas upstream of the first catalyst layer in excess of the stoichiometric equivalent of the nitrogen oxides in the exhaust gas, flowing the exhaust gas through the first catalyst layer, selectively catalytically decomposing ammonia in excess of the stoichiometric reaction equivalent of the nitrogen oxides in the exhaust gas, and catalytically reducing the nitrogen oxides by reaction with ammonia not selectively catalytically decomposed.

Abstract: The present invention provides a method for removing mercury in exhaust gas, in which mercury in exhaust gas discharged from combustion equipment is removed, characterized by including a mercury oxidation process in which mercury in the exhaust gas is converted to mercury chloride in the presence of a catalyst; a contact process in which the exhaust gas is brought into contact with an absorbing solution in a scrubber to absorb and remove mercury components from the exhaust gas; and a control process in which blowing of air or addition of an oxidizing agent into the scrubber is accomplished, and the amount of blown air or the added amount of oxidizing agent is regulated to control the oxidation-reduction potential of the absorbing agent, and a system for removing mercury in exhaust gas. According to the mercury removing method in accordance with the present invention, a phenomenon that mercury chloride is reduced into metallic mercury by SO2 etc.

Abstract: The present invention provides a system for removing mercury in exhaust gas, in which mercury is removed from exhaust gas of a boiler, characterized in that between a denitrification apparatus and a wet type desulfurization apparatus, an NH3 decomposition catalyst and a mercury oxidation catalyst are provided, and mercury having been oxidized into mercury chloride is removed by the wet type desulfurization apparatus. Also, it provides a method for removing mercury in exhaust gas, characterized in that the mercury removing method includes an NH3 decomposition process and a mercury oxidation process, which are provided between the denitrification process and a wet desulfurization process, and mercury having been oxidized into mercury chloride is removed in the wet desulfurization process.

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: 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: 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.