A process for preparing a catalyst material, includes: (a) providing a support material having surface hydroxyl (OH) groups, the support material is ceria (CeO.sub.2), zirconia (ZrO.sub.2) or a combination, and the support material contains between 0.3 and 2.0 mmol OH groups/g of the support material; (b) reacting the support material with at least one of: (b1) a compound containing at least one alkoxy or phenoxy group bound though its oxygen atom to a metal element from Group 5 (V, Nb, Ta) or Group 6 (Cr, Mo, W); (b2) a compound containing at least one hydrocarbon group bound though a carbon atom to a metal element from Group 5 or 6; (b3) a compound containing at least one hydrocarbon group bound though a carbon atom to a metal element which is copper (Cu); and (c) calcining the product obtained in step (b).

The present invention pertains to a catalyst for use in the selective catalytic reduction (SCR) of nitrogen oxides comprising: • a monolithic substrate and • a coating A which comprises an oxidic metal carrier comprising an oxide of titanium and a catalytic metal oxide which comprises an oxide of vanadium wherein the mass ratio vanadium/titanium is 0.07 to 0.26.

The exhaust gas-purifying catalyst of the invention includes a noble metal, and crystallites that form CZ composite metal particles which serve as a carrier supporting the noble metal and contain at least zirconium (Zr) and cerium (Ce). The CZ composite oxide particles (crystallites) further contain crystal growth-suppressing fine particles which are fine metal particles comprising primarily a metallic element M that melts at 1,500° C. or above and which suppress crystal growth by the CZ composite oxide particles. The content of the metallic element M included in the CZ composite oxide particles, expressed in terms of the oxide thereof, is 0.5 mol % or less of the total oxide.

A bimetal oxysulfide solid-solution catalyst is provided. The bimetal oxysulfide solid-solution catalyst is represented by the following formula:
Cu.sub.xM.sup.(2).sub.yO.sub.zS.sub.γ wherein M.sup.(2) includes monovalent Silver (Ag), divalent Zinc (Zn), Manganese (Mn), Nickel (Ni), Cobalt (Co), and Tin (Sn.sup.II), trivalent Indium (In), Cerium (Ce), Antimony (Sb), and Gallium (Ga), tetravalent Tin (Sn.sup.IV), or pentavalent Molybdenum (Mo), 0<y<0.3, 0.7<x<1.0, 0<z<0.5, and 0.5<γ<1.0. In addition, a manufacturing method of the bimetal oxysulfide solid-solution catalyst and applications of the bimetal oxysulfide solid-solution catalyst are also provided.

Catalytic articles having a high porosity substrate containing platinum, palladium or a mixture thereof, in walls of the high porosity substrate and an SCR catalyst coating on a wall of the high porosity substrate are disclosed. The platinum, palladium or mixture thereof can be present in the wall of the high porosity support as a metal, or as a supported platinum, palladium or a mixture thereof. The catalytic articles are useful for selective catalytic reduction (SCR) of NOx in exhaust gases and in reducing the amount of ammonia slip. Methods for producing such articles are described. Methods of using the catalytic articles in an SCR process, where the amount of ammonia slip is reduced, are also described.

A method comprising treating combustion exhaust gas containing nitrogen oxides in the presence of a denitration catalyst to remove nitrogen oxides from the combustion exhaust gas, wherein the denitration catalyst is composed of a shaped product comprising a catalyst component, the shaped product has micro cracks in a mesh pattern or a bipectinate pattern on the surface of the shaped product, and the micro cracks have a 95% crack width of 100 μm or less and a crack area ratio variation coefficient of 0.7 or less.

Provided is a combustion system in which a catalyst having superior denitration efficiency at a low temperature compared with those used in the conventional techniques is used in a selective catalytic reduction reaction using ammonia as a reducing agent. A combustion system equipped with: a denitration device which is arranged in the exhaust passage and can remove a nitrogen oxide from the exhaust gas with a denitration catalyst. In the combustion system, the denitration device is arranged on the downstream side of the dust collection device in the exhaust passage, and the denitration catalyst is one which contains vanadium oxide as the main component and in which the content of a second metal in terms of oxide content is 1 to 40 wt % inclusive, wherein the second metal comprises at least one metal element selected from the group consisting of Co, W, Mo, Nb, Ce, Sn, Ni, Fe, Cu, Zn and Mn.

It is an object to provide a regenerated denitration catalyst whose denitration performance is restored compared with a denitration catalyst before use, utilizing a spent denitration catalyst, and a method for manufacturing the same. In a regenerated denitration catalyst according to the present disclosure, a spent denitration catalyst including a first titanium oxide as a main component, and a second titanium oxide are mixed. The spent denitration catalyst is already used in a denitration reaction in which nitrogen oxides in a gas are decomposed into nitrogen and water using a reducing agent. The second titanium oxide has a larger specific surface area per unit weight than the first titanium oxide. A content of the second titanium oxide based on a total weight of the first titanium oxide and the second titanium oxide is preferably 10% by weight or more and 90% by weight or less.

A method for preparing an active catalyst for high-efficiency denitration is disclosed. The method includes: a catalyst raw material is charged into a denitration reactor, NH.sub.3 and an inert gas are introduced and then heating is performed, and the temperature is held and then natural cooling is performed, thereby obtaining the catalyst. The active catalyst can greatly improve the denitration activity in low temperature range, and can not only improve the denitration efficiency under the condition without SO.sub.2 and H.sub.2O, but also can improve the denitration efficiency under the condition with both SO.sub.2 and H.sub.2O. The service life of the catalyst is prolonged under the premise of not changing the existing catalyst preparation process, and the economic benefit is significant. The denitration efficiency of a powder catalyst can be increased by 25%, and the denitration efficiency of a honeycombed catalyst or a corrugated catalyst can be increased by 20%.

A gas purification device includes: a converter packed with a catalyst for hydrolyzing both carbonyl sulfide and hydrogen cyanide; an upstream heat exchanger for heat exchange between a gas to be introduced into the converter and a cooling fluid for cooling the gas; a reaction-temperature estimation member for estimating a reaction temperature inside the converter; and a flow-rate adjustment member for adjusting a flow rate of the cooling fluid flowing into the upstream heat exchanger based on an estimated value of the reaction-temperature estimation member to control the reaction temperature.