The present invention relates to a catalyst composition comprising a support, catalytically active species comprising a vanadium species, an antimony species and a tungsten species, and optionally, at least one further species selected from the group consisting of silicon species, aluminum species, zirconium species, titanium species, and cerium species; a catalytic article comprising the same, a method for preparing the catalytic article, and use of the catalyst composition or the catalytic article for selective catalytic reduction of nitrogen oxides in exhaust gases.

Denitration catalyst unit, comprising two or more platy catalyst elements, wherein the platy catalyst element has an edge located on gas-inflow side, an edge located on gas-outflow side and edges located on either side of the platy catalyst element, the platy catalyst elements are piled so as to align the edges located on gas-inflow side and the edges located on either side of the platy catalyst elements respectively, each of the platy catalyst elements alternately has more than one flat part in the shape of a flat plate and more than one concavo-convex part in the shape of platy convex strips on the upper and lower surfaces, the platy convex strips are parallel to one another and are obliquely disposed at an angle θ of not less than 50° and not more than 85° to an extending direction of the edge located on gas-inflow side of the platy catalyst element so that a ridge of the platy convex strip on the upper surface of one of the platy catalyst elements intersects with a ridge of the platy convex strip on the lower surface of another of the platy catalyst elements adjacent, at least one of the intersection points is within a range x of more than 0 mm and less than 25 mm inward from the edge located on gas-inflow side of the platy catalyst element.

The present invention belongs to the technical field of functional organic macromolecule composite catalysts and involves the preparation of a nitrogen-doped lattice macromolecule composite loaded with an efficient denitrification and sulfur resistance catalyst, firstly using the method of adding metal salts to make a large amount of Ce.sup.3+, Ce.sup.4+, Sn.sup.3+ and Sn.sup.4+ ions accumulate around the cyanuric acid molecule. Afterwards, 2,4,6-triaminopyrimidine and cytosine were added to graft with the cyanuric acid to produce the N-doped macromolecule in the first stage. After that, potassium permanganate was used as the oxidizing agent, and redox reaction occurred on the surface of N-doped macromolecules, so that the manganese cerium tin catalyst was grown in situ on the surface of N-doped macromolecules, and finally calcined at once to cross-link the N-doped macromolecules to generate catalyst composites. The catalysts described in this invention have higher efficient NOx reduction and sulfur resistance performance.

Provide is a functional structural body that can suppress aggregation of metal oxide nanoparticles and prevent functional loss of metal oxide nanoparticles, and thus exhibit a stable function over a long period of time. A functional structural body (1) includes: a skeletal body (10) of a porous structure composed of a zeolite-type compound; and at least one type of metal oxide nanoparticles (20) containing a perovskite-type oxide present in the skeletal body (10), the skeletal body (10) having channels (11) that connect with each other, and the metal oxide nanoparticles (20) being present at least in the channels (11) of the skeletal body (10).

Described is a device (1) for reducing pollutants in a gaseous mixture comprising: •a containment body (2) having an inlet portion (3) for the gaseous mixture and an outlet portion (4) for the gaseous mixture, the containment body (2) imposing on the gaseous mixture a fixed direction of flow (D), •at least one filtering unit (10) comprising a photocatalytic filter (7) interposed, along the fixed direction of flow (D), between a first light source (6a) and a second light source (6b), both having a wavelength in the visible spectrum (400-700 nm), the photocatalytic filter (7) comprising a photocatalytic nanoparticle coating and the nanoparticle coating comprising titanium dioxide doped with a nitrogen doping agent. •a unit (5) for straightening the flow before the filtering unit (10).

Process for the removal of NOx (NO, NO2) and nitrous oxide (N2O) contained in a process off-gas comprising the steps of (a) adding an amount of a NOx reducing agent into the process off-gas;(b) in a first stage passing the process off-gas admixed with the reducing agent through a catalyst active in selective catalytic reduction of NOx with the reducing agent and providing an effluent gas comprising the nitrous oxide and residual amounts of reducing agent; and(c) in a second stage passing the effluent gas through a catalyst comprising a cobalt compound and being active in decomposition of nitrous oxide and oxidation of the residual amounts of the reducing agent.

A Nitrogen Oxide (NOx) sorbent material of the present invention includes a multi-metallic oxide that includes one or more alkali or alkaline earth metal, one or more 3d transition metal, and one or more rare earth element. The NOx sorbent material is configured to adsorb and absorb NOx below a low temperature and to release the adsorbed or absorbed NOx at temperature at or above the low temperature. In some embodiments, a manganese catalyst is deposited on a high surface area carrier. The manganese catalyst takes the form of an alkali/metal promotor and an Mn-based compound. In general, the NOx sorbent material contains about one percent to about fifty percent by weight of alkali/alkaline earth metal manganese catalyst based on the total weight of the catalyst.

An AFX framework type zeolite having a SiO.sub.2/Al.sub.2O.sub.3 molar ratio of greater than 50 is disclosed. The high-silica AFX framework type zeolite is synthesized from a reaction mixture having high silica and low hydroxide concentrations in the presence of an organic structure directing agent comprising 1,3-bis(1-adamantyl)imidazolium cations.

A method of selectively catalysing the reduction of oxides of nitrogen (NO.sub.x) including nitrogen monoxide in an exhaust gas of a stationary source of NO.sub.x emissions also containing oxides of sulfur (SO.sub.x) comprising the steps of passively oxidising nitrogen monoxide to nitrogen dioxide (NO.sub.2) over an oxidation catalyst comprising a platinum group metal so that a NO.sub.2/NO.sub.x content is from 40-60%; introducing a nitrogenous reductant into the exhaust gas; and contacting exhaust gas having the 40-60% NO.sub.2/NO.sub.x content and containing the nitrogenous reductant with a selective catalytic reduction (SCR) catalyst comprising an aluminosilicate zeolite promoted with copper.

Zeolites having highly dispersed bimetallic clusters, uniformly distributed in size and composition, encapsulated therein are disclosed. Metal encapsulation and alloying is conferred by introducing ligated metal cation precursors into zeolite synthesis gels, which are subsequently crystallized hydrothermally to form zeolites with metal cations occluded in the pores. The ligated cations are anchored to the zeolite framework via siloxane bridges which enforces their uniform dispersion throughout the zeolite crystals. Treatment of the crystallized zeolites in O.sub.2 and then H.sub.2 forms bimetallic clusters, which remain narrowly distributed in size and composition.