Abstract: Briefly, in one aspect, a catalytic assembly described herein comprises a module comprising at least one layer of structural catalyst bodies having an inlet face for receiving a gas stream. A diffuser assembly is arranged a distance of greater than 50 mm from the inlet face, the diffuser assembly including at least one diffuser element comprising a plurality of apertures, wherein a ratio of aperture length (L) in the gas stream flow direction to aperture hydraulic diameter (Da) is less than 1.

Abstract: In one aspect, catalyst modules are described herein comprises structural catalyst bodies having cross-sectional flow channel geometries and surface features for enhanced catalytic activity. In some embodiments, the catalyst modules and associated structural catalyst bodies are suitable for use in high particulate matter environments. Briefly, a catalyst module comprises a framework and a plurality of structural catalyst bodies positioned in the framework, a structural catalyst body comprising an outer peripheral wall and a plurality of inner partition walls forming individual flow channels of rectangular cross-section, the outer peripheral wall resistant to localized flexural failures induced by material between adjacent structural catalyst bodies of the module.

Abstract: Briefly, in one aspect, a catalytic assembly described herein comprises a module comprising at least one layer of structural catalyst bodies having an inlet face for receiving a gas stream. A diffuser assembly is arranged a distance of greater than 50 mm from the inlet face, the diffuser assembly including at least one diffuser element comprising a plurality of apertures, wherein a ratio of aperture length (L) in the gas stream flow direction to aperture hydraulic diameter (Da) is less than 1.

Abstract: Briefly, in one aspect, a catalytic assembly described herein comprises a module comprising at least one layer of structural catalyst bodies having an inlet face for receiving a gas stream. A diffuser assembly is arranged a distance of greater than 50 mm from the inlet face, the diffuser assembly including at least one diffuser element comprising a plurality of apertures, wherein a ratio of aperture length (L) in the gas stream flow direction to aperture hydraulic diameter (Da) is less than 1.

Abstract: In one aspect, catalyst modules are described herein comprises structural catalyst bodies having cross-sectional flow channel geometries and surface features for enhanced catalytic activity. In some embodiments, the catalyst modules and associated structural catalyst bodies are suitable for use in high particulate matter environments. Briefly, a catalyst module comprises a framework and a plurality of structural catalyst bodies positioned in the framework, a structural catalyst body comprising an outer peripheral wall and a plurality of inner partition walls forming individual flow channels of rectangular cross-section, the outer peripheral wall resistant to localized flexural failures induced by material between adjacent structural catalyst bodies of the module.

Abstract: Briefly, in one aspect, a catalytic assembly described herein comprises a module comprising at least one layer of structural catalyst bodies having an inlet face for receiving a gas stream. A diffuser assembly is arranged a distance of greater than 50 mm from the inlet face, the diffuser assembly including at least one diffuser element comprising a plurality of apertures, wherein a ratio of aperture length (L) in the gas stream flow direction to aperture hydraulic diameter (Da) is less than 1.

Abstract: In one aspect, structural catalyst bodies are described herein having cross-sectional flow channel geometries and surface features for enhanced catalytic activity. A structural catalyst body comprises an outer peripheral wall and a plurality of inner partition walls defining individual flow channels of rectangular cross-section, wherein one or more of the inner partition walls comprise surface protrusions, surface indentations or combinations thereof.

Abstract: In one aspect, structural catalyst bodies comprising one or more gradients of catalytic material are provided herein. In some embodiments, a structural catalyst body described herein comprises an inner partition wall having a first surface and a second surface opposite the first surface, the inner partition wall having a gradient of catalytic material along the width of the inner partition wall.

Abstract: In one aspect, catalytic assemblies are described herein. A catalytic assembly, in some embodiments, comprises a plurality of honeycomb catalyst segments bonded to one another by a bonding material, the honeycomb catalyst segments comprising an outer peripheral wall and a plurality of inner partition walls defining flow channels extending longitudinally through the catalyst segments, wherein the outer peripheral wall and inner partition walls have dispersed throughout a chemical composition comprising 50-99.9 weight percent an inorganic oxide composition and at least 0.1 weight percent a catalytically active metal functional group.

Abstract: In one aspect, catalytic assemblies are described herein. A catalytic assembly, in some embodiments, comprises a plurality of honeycomb catalyst segments bonded to one another by a bonding material, the honeycomb catalyst segments comprising an outer peripheral wall and a plurality of inner partition walls defining flow channels extending longitudinally through the catalyst segments, wherein the outer peripheral wall and inner partition walls have dispersed throughout a chemical composition comprising 50-99.9 weight percent an inorganic oxide composition and at least 0.1 weight percent a catalytically active metal functional group.

Abstract: In one aspect, structural catalyst bodies comprising one or more gradients of catalytic material are provided herein. In some embodiments, a structural catalyst body described herein comprises an inner partition wall having a first surface and a second surface opposite the first surface, the inner partition wall having a gradient of catalytic material along the width of the inner partition wall.

Abstract: In one aspect, structural catalyst bodies comprising one or more gradients of catalytic material are provided herein. In some embodiments, a structural catalyst body described herein comprises an inner partition wall having a first surface and a second surface opposite the first surface, the inner partition wall having a gradient of catalytic material along the width of the inner partition wall.

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: In one aspect, structural catalyst bodies comprising one or more gradients of catalytic material are provided herein. In some embodiments, a structural catalyst body described herein comprises an inner partition wall having a first surface and a second surface opposite the first surface, the inner partition wall having a gradient of catalytic material along the width of the inner partition wall.

Abstract: In one aspect, combustion apparatus are described herein which, in some embodiments, can provide advantageous NOx loads while mitigating the formation of SCR catalyst deactivation species in the flue gas stream. In some embodiments, a combustion apparatus described herein comprises a furnace providing a flue gas stream, the furnace comprising a primary combustion zone having an air to fuel stoichiometric ratio ranging from 0.89 to 1.05 and air staging apparatus associated with the furnace.

Abstract: Structural catalyst bodies are described herein which, in some embodiments, can be used in the treatment of nitrogen oxides present in exhaust or flue gases from stationary or mobile combustion sources. In some embodiments, a structural catalyst body described herein comprises an outer peripheral wall and a plurality of inner partition walls having an average thickness less than about 0.5 mm, the outer peripheral wall and the inner partition walls having dispersed throughout a chemical composition comprising 50-99.9% by weight an inorganic oxide composition, less than 3% by weight an inorganic extrusion aid and at least 0.1% by weight a catalytically active metal functional group comprising vanadium, the structural catalyst body having a crystalline vanadium pentoxide content less than 0.1 weight percent.

Abstract: The present invention provides monolithic structural catalysts. The catalysts have a thin wall structure and are advantageous for catalyzing reactions of gaseous fluid or liquid fluid molecules, such as the denitration or selective catalytic reduction (SCR) of nitrogen oxides (NOx) in combustion flue gases. In an embodiment, the honeycomb-like monolithic structural body includes catalytically active outer peripheral walls and a plurality of catalytically active thin-walled inner partition walls, the thin-walled inner partition walls adapted to enhance fluid flow through the monolithic catalytic body and to increase interaction of the fluid molecules with the catalyst body.

Abstract: In one aspect, structural catalyst bodies comprising one or more gradients of catalytic material are provided herein. In some embodiments, a structural catalyst body described herein comprises an inner partition wall having a first surface and a second surface opposite the first surface, the inner partition wall having a gradient of catalytic material along the width of the inner partition wall.

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 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.