A method for removing nitrogen oxides NOx from a gaseous current, comprising the steps of: passing the gaseous current through a de-NOx catalytic bed with iron exchanged zeolite as a catalyst with the addition of ammonia as a reducing agent, wherein the molar ratio of NH3 over NOx is greater than 1.33.

The invention relates to a catalytic article comprising a substrate having an inlet and an outlet; a first coating comprising a blend of: (1) platinum on a support, and (2) a first SCR catalyst comprising a Cu- and Mn-exchanged molecular sieve; and a second coating comprising a second SCR catalyst; wherein the support comprises at least one of a zeolite or a SiO.sub.2-Al.sub.2O.sub.3 mixed oxide. The platinum may be fixed on the support in solution.

An oxidation catalyst composite, methods, and systems for the treatment of exhaust gas emissions from a diesel engine are described. More particularly, an oxidation catalyst composite including a first washcoat layer comprising a Pt component and a Pd component, and a second washcoat layer including a refractory metal oxide support containing manganese, a zeolite, and a platinum component is described.

An oxidation catalyst composite, methods, and systems for the treatment of exhaust gas emissions from a diesel engine are described. More particularly, an oxidation catalyst composite including a first washcoat layer comprising a Pt component and a Pd component, and a second washcoat layer including a refractory metal oxide support containing manganese, a zeolite, and a platinum component is described.

The present invention provides a method for catalytic oxidation of alkanes, where the catalyst comprises a photoactive material that is activated when the catalyst is irradiated with UV light. In particular, the method is for the catalytic oxidation of a C1-C5 alkane using an oxidation catalyst comprising a photoactive material, said method comprising the steps of a) activating the photoactive material by irradiating the catalyst with UV light and b) contacting the activated catalyst with a gaseous feedstream comprising an amount of C1-C5 alkane at a temperature of from 150° C. to 600° C.

This invention belongs to the technical field of green preparation of environmentally friendly catalysts, and discloses a preparation method and application of mesoporous FeCu—ZSM-5 molecular sieve, in particular to a method for synthesizing mesoporous FeCu—ZSM-5 molecular sieve by one-pot method and the application in selective catalytic reduction (SCR) denitration reaction. This invention firstly proposes to combine the two calcinations after demolding and ion exchange into one, that is, the original powder is directly calcined to prepare a FeCu—ZSM-5 molecular sieve. The molecular sieve has several advantages such as window with wide temperature window, low cost, good hydrothermal stability and high SCR denitrification activity. Besides, the synthesis process does not use a (large) pore template, nor does it use a post-treatment method to construct the mesopores. Therefore, the method of the invention not only has the advantages of simple process, simple operation, but also good economic and environmental benefits.

A method for removing nitrogen oxides NOx from a gaseous current, comprising the steps of: passing the gaseous current through a de-NOx catalytic bed with iron exchanged zeolite as a catalyst with the addition of ammonia as a reducing agent, wherein the molar ratio of NH3 over NOx is greater than 1.33.

The invention relates to a catalytic article comprising a substrate having an inlet and an outlet; a first coating comprising a blend of: (1) platinum on a support, and (2) a first SCR catalyst comprising a Cu- and Mn-exchanged molecular sieve; and a second coating comprising a second SCR catalyst; wherein the support comprises at least one of a zeolite or a SiO.sub.2-Al.sub.2O.sub.3 mixed oxide. The platinum may be fixed on the support in solution.

The present invention relates to a catalyst comprising a carrier substrate of the length L extending between substrate ends a and b and two washcoat zones A and B, wherein washcoat zone A comprises a zeolite having a smallest lower channel width of at least 0.4 nm and extends starting from substrate end a over a part of the length L, and washcoat zone B comprises the same components as washcoat A and palladium and extends from substrate end b over a part of the length L, wherein L=L.sub.A+L.sub.B, wherein L.sub.A is the length of washcoat zone A and L.sub.B is the length of substrate length B.

SCR-active molecular-sieve based catalysts with improved low-temperature performance are made by heating a molecular-sieve in a non-oxidizing atmosphere with steam (hydrothermal treatment), or in a reducing atmosphere without steam (thermal treatment), at a temperature in the range of 600-900° C. for a time period from 5 minutes to two hours. The resulting SCR-active iron-containing molecular sieves exhibit a selective catalytic reduction of nitrogen oxides with NH.sub.3 or urea at 250° C. that is at least 50% greater than if the iron-containing molecular-sieve were calcined at 500° C. for two hours without performing the hydrothermal or thermal treatment.