Abstract: A catalyst for removal of NOx from exhaust gas, containing cerium oxide and titanium dioxide, wherein a first portion of the cerium oxide forms at least one agglomerate of cerium oxide crystallites interdispersed in the titanium dioxide, and a second portion of the cerium oxide forms at least one island on a surface of the titanium dioxide, a method for producing the catalyst, a process for selectively reducing NOx levels in an exhaust gas using the catalyst, and an SCR canister containing the catalyst therein.

Abstract: A method of providing an exhaust treatment device is disclosed. The method includes applying a catalyst including gold and a platinum group metal to a particulate filter. The concentration of the gold and the platinum group metal is sufficient to enable oxidation of carbon monoxide and nitric oxide.

Abstract: The air pollution control device includes: NH4Cl solution supply means 16 for spraying an NH4Cl solution 14 by a plurality of spray nozzles 15 into a flue gas duct 13 at the downstream of the boiler 11; a reduction-denitration device 18 including a denitration catalyst for reducing NOx in the flue gas 12 with NH3 and for oxidizing Hg under the coexistence with HCl; and a wet desulfurization device 22 for reducing the amount of Hg oxidized in the reduction-denitration device 18 by using a limestone-gypsum slurry 21. The NH4Cl solution supply means 16 supplies the NH4Cl solution 14 from the spray nozzles 15 so as to prevent the NH4Cl solution 14 from being adhered to an inner wall of the flue gas duct 13 through which the flue gas 12 is flowing.

Abstract: A system and method for NOx reduction is described, with a catalytic unit including a first zeolite catalyst with a first NOx conversion performance in a first temperature range and a second NOx conversion performance, lower than said first NOx conversion performance, in a second temperature range. The catalytic unit also comprises a second zeolite catalyst with a third NOx conversion performance, lower than said first NOx conversion performance, in the first temperature range and a fourth NOx conversion performance, higher than said second and third NOx conversion performances in the second temperature range, said first temperature range being higher than said second temperature range. The system further includes a controller configured to adjust an amount of reducing agent added to the NOx reducing system responsive to a temperature of the catalytic unit.

Abstract: A catalyst and its use for the abatement of carbon monoxide and unburned hydrocarbons in the exit stream of a combustion device, such as an automobile and spray paint booths are disclosed.

Abstract: One embodiment of the invention includes a method of treating a gas stream comprising flowing the gas stream over a hydrocarbon reduction and NOx reduction catalyst first, and thereafter flowing the gas over a perovskite and NOx trap material for NOx oxidation and storage. In one embodiment, the hydrocarbon reduction and NOx reduction catalyst may include palladium. In one embodiment, the perovskite catalyst may have the general formula ABO3, AA?BO3, ABB?O3, or AA?BB?O3. The perovskite catalyst may be the only catalyst or a second non-perovskite catalyst may include at least one of palladium, platinum, rhodium, ruthenium or a catalyst system including one or more of the same or alloys thereof. In one embodiment, the NOx trap material may include at least one of alkali metals, alkaline earth metals such as barium, calcium, potassium, or sodium.

Abstract: A process and an apparatus denox flue gases containing carbon monoxide and/or gaseous organic substances with at least one catalyst for catalytic reduction of the nitrogen oxide NOx and a heat exchanger for heating the flue gases from recovery of the residual heat of the denoxed flue gases before the catalytic reduction to a reaction temperature of 160° C. to 500° C. For the best possible denoxing of the flue gases with simultaneous minimization of the externally supplied energy needed, it is envisaged that the losses associated with the heat movement in the heat exchanger will be compensated for by providing at least one stage for regenerative post combustion of the carbon monoxide and/or of the gaseous organic substances.

Abstract: A system and method of reducing NOx emissions from a lean burn combustion source is provided. The system includes at least one injection lance having a elongated shaft with distal and proximal ends, a metering valve positioned at the distal end, an atomization chamber positioned between the metering valve and the distal end, a storage chamber for containing a reagent fluidly connected to the metering valve, an injection tip positioned at the proximal end for delivering the reagent, and at least one air port for supplying air to the atomization chamber. The injection lance is positioned in the combustion source, and the reagent is supplied from the storage chamber to the injection lance at an inlet pressure. The reagent is then injected into the combustion source via the injection lance, wherein a temperature of the reagent prior to the injection is maintained below a hydrolysis temperature of the reagent.

Abstract: A catalyst for treating exhaust gases containing nitrogen monoxide, carbon monoxide and volatile organic compounds includes a plurality of layers, an upper layer of which has an active component contained uniformly therein and a lower layer of which has no active component contained therein. The catalyst is obtained through the steps of: forming the lower layer by coating the surface of substrate with a slurry of a porous inorganic compound, followed by drying; and forming the upper layer, which is to be the top surface of the catalyst, by coating the surface of the lower layer with a slurry of a porous inorganic compound that has the active component composed of one or more precious metals supported thereon, followed by drying. The oxidation power of the resulting catalyst is enhanced without increasing the amount of precious metal supported thereon.

Abstract: The invention provides a system for regenerative selective catalytic reduction including a catalyst chamber that contains a catalyst for reducing NOX in a gas stream passing therethrough. The system also includes a reactant injector, first and second heat exchangers, and a valve manifold adapted to direct a substantially continuous gas stream through the heat exchangers and catalyst chamber in such a manner as to flow through the catalyst chamber in the same flow direction during each cycle of the system. The invention also provides a process of regenerative selective catalytic reduction wherein the gas stream through the catalyst chamber flows in the same flow direction during each cycle of the process.

Abstract: A selective catalytic reduction system and method for reducing nitrogen oxide (NOx) emissions comprising a boiler producing flue gas emissions, a particulate control device receiving flue gas emissions from the boiler, a selective catalytic reduction unit (SCR) receiving flue gas emissions from the particulate control device and reducing nitrogen oxide (NOx) emissions, and a heat exchanger located downstream of the selective catalytic reduction unit (SCR) for removing heat from the flue gas for preheating at least one of boiler feed water and combustion air for the boiler.

Abstract: Low temperature activity of a vanadium-free selective catalytic reduction catalyst is provided by a mixed metal oxide support containing oxides of titanium and zirconium, the support having a promoter deposited on the surface of the mixed metal oxide support, and further having an active catalyst component deposited over the promoter on the mixed metal oxide support surface. Suitable promoters include oxides of silicon, boron, aluminum, cerium, iron, chromium, cobalt, nickel, copper, tin, silver, niobium, lanthanum, titanium, and combinations thereof. Suitable active catalyst components include oxides of manganese, iron and cerium.

Abstract: One embodiment of the invention may include a method comprising providing a product comprising a substrate comprising a perovskite catalyst, NOx stored in or on the substrate and particulate matter in or on the substrate; releasing at least some of the stored NOx and oxidizing the released NOx to form NO2, and reacting the NO2 with carbon in the particulate matter to form at least one of CO or CO2.

Abstract: A catalyst system to be used in an automobile exhaust gas purification apparatus which exerts excellent purification capability to a nitrogen oxide, even when hydrocarbon concentration varies, by subjecting exhaust gas discharged from an automotive internal engine to contacting with a catalyst, an exhaust gas purification apparatus using the same, and an exhaust gas purification method. A catalyst system etc.

Abstract: The present invention relates to a catalyst for removing nitrogen oxides from an exhaust gas, a method for preparing the same and a method for removing nitrogen oxide in an exhaust gas using the same, and more particularly, to a catalyst for removing nitrogen oxides from the exhaust gas in which a ceramic fiber carrier is treated by hydrothermal reaction prior to washcoating to improve the hydrothermal stability of catalyst, a method for preparing the same and a method for removing nitrogen oxide in an exhaust gas using the same. The catalyst prepared according to the present invention has excellent hydrothermal stability and an activity of the catalyst remains for a long time. Further, by using this catalyst to remove nitrogen oxides in an exhaust gas, a removal ratio of the nitrogen oxides is greatly enhanced.

Abstract: An article for treating a gas containing nitrogen oxides having a monolith substrate loaded with a catalytic composition containing at least one catalytic component consisting of (i) at least one transition metal dispersed on a mixed oxide or composite oxide or a mixture thereof as support material consisting of cerium and zirconium; or (ii) cerium oxide and zirconium oxide as single oxides or a composite oxide thereof or a mixture of the single oxides and the composite oxide dispersed on an inert oxide support material, wherein at least one transition metal is dispersed thereon, wherein the at least one transition metal is selected from the group consisting of a metal from Group VIB, IB, IVA, VB, VIIB, and VIII and mixtures of any two or more thereof, provided that at least one selected transition metal is tungsten, wherein the catalytic composition is disposed on said monolith substrate.

Abstract: A method for purifying waste gases of an at least partially burnt solid fuel to reduce pollutants such as SOx and/or HCl and NOx. The waste gas flows into a moving bed reactor from below through a lower and upper layer of an adsorption and/or absorption agent already polluted with NOx, SOx and/or HCl. SOx and/or HCl components are adsorbed from the waste gas into the NOx loaded adsorption and/or absorption agent. Thereafter, the waste gas is mixed with an ammonium-containing compound and flows through an upper horizontal gas inflow and bulk material removal tray of the moving bed reactor into the upper layer of the adsorption and/or absorption agent already polluted with NOx and small quantities of SOx and/or HCl. During the throughflow of the upper layer, NOx components are adsorbed from the waste gas onto the adsorption/absorption agent.

Abstract: Catalysts, catalyst systems, and methods for removing ammonia and/or carbon monoxide in flue gases are provided where ammonia is used with a selective catalytic reduction catalyst for reducing oxides of nitrogen. A dual oxidation catalyst generally comprises an alkali component, a transition metal, and a metal oxide support. This catalyst is also substantially free from precious metal components and effective for substantially simultaneously oxidizing ammonia (NH3) and carbon monoxide (CO) when placed in an exhaust gas stream. The catalyst is effective to provide low ammonia to nitrogen oxides selectivity.

Abstract: The invention provides a N2O removal method for a waste gas which is capable of stably decomposing and removing N2O even if the steam concentration in the waste gas is fluctuated. N2O is reduced and removed by bringing the waste gas containing N2O into contact with a reducing agent in the presence of a N2O decomposition catalyst. The temperature of the waste gas to be brought into contact with the N2O decomposition catalyst or the addition amount of the reducing agent is controlled in accordance with the steam concentration in the waste gas in a prior stage of the N2O decomposition catalyst. Therefore, the N2O decomposition efficiency is prevented from being decreased. An iron-zeolite based catalyst may be used as the N2O decomposition catalyst and methane, propane, ammonia, etc. may be used as the reducing agent.

Abstract: One embodiment of the invention includes a method of treating a gas stream comprising flowing the gas stream over a hydrocarbon reduction and NOx reduction catalyst first, and thereafter flowing the gas over a perovskite and NOx trap material for NOx oxidation and storage. In one embodiment, the hydrocarbon reduction and NOx reduction catalyst may include palladium. In one embodiment, the perovskite catalyst may have the general formula ABO3, AA?BO3, ABB?O3, or AA?BB?O3. The perovskite catalyst may be the only catalyst or a second non-perovskite catalyst may include at least one of palladium, platinum, rhodium, ruthenium or a catalyst system including one or more of the same or alloys thereof. In one embodiment, the NOx trap material may include at least one of alkali metals, alkaline earth metals such as barium, calcium, potassium, or sodium.

Abstract: Various systems, devices, NO2 absorbents, NO2 scavengers and NO2 recuperator for generating nitric oxide are disclosed herein. According to one embodiment, an apparatus for converting nitrogen dioxide to nitric oxide can include a receptacle including an inlet, an outlet, a surface-active material coated with an aqueous solution of ascorbic acid and an absorbent wherein the inlet is configured to receive a gas flow and fluidly communicate the gas flow to the outlet through the surface-active material and the absorbent such that nitrogen dioxide in the gas flow is converted to nitric oxide.

Abstract: A method includes contacting a catalyst including a metal having an average particle size of approximately one nanometer or greater with SO2; and reducing the average particle size of the metal.

Abstract: The present invention relates to the use of solids consisting of a metal-organic framework (MOF) and having the units of the following formula (I): MmOkXILp as a nitrogen-oxide catalyst. The present invention also relates to devices for enabling the implementation of said use. The nitrogen oxides in question are nitrogen monoxide and nitrogen dioxide, collectively referred to as NOx. The MOF solids of the present invention are advantageously capable of removing nitrogen oxides from a liquid or gaseous effluent, for example from water, from the exhaust gases of a vehicle, factory, workshop, laboratory, stored products, urban air vents, etc., without any reducing agent and at a low temperature. The DeNOx catalysis is a major issue for our societies. The invention can be used for reducing or even avoiding the consequences for public health of the toxic NOx gases resulting from human activity.

Abstract: Dry-scrubbing media compositions, methods of preparing same, and methods of use are provided. The compositions contain activated alumina and potassium carbonate. Optionally, activated carbon and other impregnates, such as sulfates of group 1A metals, are included in the compositions. The compositions exhibit improved efficiency and capacity for the removal of compounds such as chlorine or sulfur dioxide from an air-stream. The compositions are particularly useful for reducing or preventing the release of toxic gaseous compounds from the areas such as petroleum storage areas, refineries, drinking water systems, sewage treatment facilities, swimming pools, hospital morgues, animal rooms, and pulp and paper production sites.

Abstract: An integrated process for operating a fossil fuel fired power plant including: producing hydrogen gas and an aqueous solution of hydrogen peroxide via a process including: dissociating hydrogen gas and oxygen gas from water; pressurizing the hydrogen gas and the oxygen gas; and mixing, under pressure, the oxygen gas and at least about a stoichiometric portion of the hydrogen gas with an aqueous solution of a catalyst and a promoter to form the aqueous solution of hydrogen peroxide; supplying a remainder of the hydrogen gas to at least one of (a) a storage means, (b) a boiler detonation cleaning system of the fossil fuel fired power plant, and (c) an electrical generator of the fossil fuel fired power plant; and injecting the aqueous solution of hydrogen peroxide into an air pollution control system of the fossil fuel fired power plant.

Abstract: Provided is a process for treating nitrogen oxide-containing exhaust produced by a stationary combustion source by the catalytic reduction of nitrogen oxide in the presence of a reductant comprising hydrogen, followed by ammonia selective catalytic reduction to further reduce the nitrogen oxide level in the exhaust.

Abstract: An exhaust treatment method is provided. Method of increasing activation of NOx reduction catalyst using two or more reductant is discussed. The NOx catalyst is disposed to receive both the exhaust stream and reductant stream. The sensor is disposed to sense a system parameter related to carbon loading of the catalyst and produce a signal corresponding to the system parameter. The controller is disposed to receive the signal and to control dosing of the reductant stream based at least in part on the signal. The method includes sensing a system parameter related to carbon loading of a catalyst, producing a signal corresponding to the system parameter and sending the signal to a controller; and controlling a dosing of a reductant stream based at least in part on the signal.

Abstract: A multi-functional cabin air filter includes a dust collecting filter layer for collecting fine dust; an oxidation catalyst filter layer for oxidizing nitrogen monoxide into nitrogen dioxide; and an adsorption filter layer for adsorbing nitrogen dioxide and volatile organic compounds, wherein antimicrobial nanoparticles are applied to at least one of the dust collecting filter layer, the oxidation catalyst filter layer and the adsorption filter layer. This cabin air filter has dust collecting, denitrifying, deodorizing and antimicrobial functions, and it may be utilized in various ways for air purification in a limited space such as a vehicle.

Abstract: Provided are exhaust systems and components suitable for use in conjunction with gasoline direct injection (GDI) engines to capture particulates in addition to reducing gaseous emission such as hydrocarbons, nitrogen oxides, and carbon monoxides. Exhaust treatment systems comprising a three-way conversion (TWC) catalyst located on a particulate trap are provided. An exemplary particulate trap is a soot filter. Additional treatment components can be added downstream of the particulate trap, including NOx traps and SCR catalysts. The TWC catalyst can be coated on both the inlet side and the outlet side of the particulate trap. Alternatively, an oxidation catalyst can be deposited on a particulate trap. Methods of making and using the same are also provided.

Abstract: A method for injection reductant into an exhaust gas and for evaporating and decomposing the reductant at an elevated temperature includes providing an exhaust pipe having an interior surface and disposing the pipe in fluid communication with and upstream of a catalyst. The method includes the steps of disposing an internal cone within the pipe generally parallel to the pipe, mounting an injector to the exterior of the pipe in fluid communication with the cone, injecting the reductant into the cone, and directing the exhaust gas in a passage between the interior surface of the pipe and the cone. The exhaust gas is directed within the cone. The flow of exhaust gas has an elevated temperature compared to an ambient. A further step includes creating a drag force on the injected reductant to increase travel time of the injected reductant from the injector to the catalyst.

Abstract: A system for reducing nitrogen oxides from an exhaust fluid is provided. The system includes an exhaust source, a hydrocarbon reductant source, a first injector in fluid communication with the hydrocarbon reductant source, where the first injector receives a first hydrocarbon reductant stream from the hydrocarbon reductant source, and expels the first portion of the hydrocarbon reductant stream. The system further includes a first catalyst that receives the exhaust stream and the first hydrocarbon reductant stream, a second injector in fluid communication with the hydrocarbon reductant source, where the second injector receives a second hydrocarbon reductant stream from the hydrocarbon reductant source, and expels the second hydrocarbon reductant stream, and a second catalyst disposed to receive an effluent from the first catalyst and the second portion of the hydrocarbon reductant stream.

Abstract: In a circulating fluidized-bed gasification system, an ammonia-off gas 30 from an ammonia remover 25 is fed to a catalytic denitrator 15 with a flow rate regulated such that a molar ratio of the ammonia in the ammonia off-gas 30 from the ammonia recover 25 to nitrogen oxides in an exhaust gas 6 from a combustion furnace 1 is kept within a setting range, and a reminder of the ammonia off-gas 30 is fed to the combustion furnace 1.

Abstract: The present invention describes the process of preparing ceramics for the absorption of ACIDIC gases, which worsen the greenhouse effect, that are released in combustion systems, or that are present in closed environments. In relation to carbon dioxide, principal target of the present invention, the process of absorption, transport, processing and transformation of the gas into other products is described. The process uses ceramic materials prepared through the solid mixture of one or more metallic oxides, with one or more binding agents and an expanding agent. The product generated can be processed and the absorbent system regenerated. The carbon dioxide obtained in the processing can be used as analytic or commercial carbonic gas, various carbamates and ammonium carbonate.

Abstract: A system to control the emissions of a fluid stream in a cyclical fashion utilizing an up-flow cycle and a down-flow cycle. The system may include a first inlet and a first outlet at a first end of the system and a second inlet and a second outlet at a second end of the system, a catalyst zone between the first end and second end, two heat transfer zones, at least one heat transfer zone positioned between the catalyst zone and the first end of the system and between the catalyst zone and the second end of the system, and two heating zones, at least one heating zone positioned between the catalyst zone and each of the at least one heat transfer zones. The symmetrical arrangement permits a bi-directional fluid cycle to recover a portion of the energy supplied to the system during each cycle.

Abstract: The present disclosure provides an AgBi catalyst over alumina suitable for performing hydrocarbon selective catalytic reduction (HC-SCR).

Abstract: According to various embodiments, a catalyst composition includes a catalytic metal secured to a porous substrate. The substrate has pores that are templated. The substrate is a product of adding a substrate precursor to a water-in-oil microemulsion including a catalytic metal salt, a solvent, a templating agent, and water.

Abstract: Low temperature activity of a vanadium-free selective catalytic reduction catalyst is provided by a mixed metal oxide support containing oxides of titanium and zirconium, the support having a promoter deposited on the surface of the mixed metal oxide support, and further having an active catalyst component deposited over the promoter on the mixed metal oxide support surface. Suitable promoters include oxides of silicon, boron, aluminum, cerium, iron, chromium, cobalt, nickel, copper, tin, silver, niobium, lanthanum, titanium, and combinations thereof. Suitable active catalyst components include oxides of manganese, iron and cerium.

Abstract: Combined removal of both ammonia from an ammonia-containing waste gas and nitrogen oxides from a nitrogen oxide-containing waste gas in a combined ammonia/urea synthesis plant is accomplished by mixing the gases and employing one or both of selective non-catalytic reduction at a temperature of 850° C. to 1100° C. or selective catalytic reduction at a temperature of 150° C. to 550° C., in which the ammonia and the nitrogen oxides react with one another to give nitrogen and water, the ammonia-containing waste gas derived from a low-pressure and/or atmospheric absorber of the urea synthesis plant, and the nitrogen oxide-containing waste gas derived from a flue gas duct of a primary reformer of the ammonia synthesis plant, both the ammonia and the nitrogen oxides of the mixed waste gas flows being depleted simultaneously during the same process step.

Abstract: The present invention relates to the selective separation of carbon dioxide (“CO2”) from methane (“CH4”) in streams containing both carbon dioxide and methane utilizing a zeolitic imidazolate framework (“ZIF”) material. Preferably, the stream to be separated is fed to the present process in a substantially gaseous phase. In preferred embodiments, the current invention is utilized in a process to separate carbon dioxide from natural gas streams preferably for sequestration of at least a portion of the carbon dioxide present in the natural gas.

Abstract: The present invention relates to the selective separation of carbon dioxide (“CO2”) from nitrogen (“N2”) in streams containing both carbon dioxide and nitrogen utilizing a zeolitic imidazolate framework (“ZIF”) material. Preferably, the stream to be separated is fed to the present process in a substantially gaseous phase. In preferred embodiments, the current invention is utilized in a process to separate carbon dioxide from combustion gas (e.g., flue gas) streams preferably for sequestration of at least a portion of the carbon dioxide produced in combustion processes.

Abstract: A system for NOx reduction in combustion gases, especially from diesel engines, incorporates an oxidation catalyst to convert at least a portion of NO to NO2, a particulate filter, a source of reductant such as NH3 and an SCR catalyst. Considerable improvements in NOx conversion are observed.

Abstract: An air pollution control system includes an emission treatment system configured to receive flue gas, to reduce at least one pollutant therefrom, and to output emission treated flue gas. A first air heater in fluid communication with the emission treatment system includes a heat exchanger for heating forced air introduced thereto above a base temperature and thereby cooling emission treated flue gas from the emission treatment system to a stack discharge temperature. A second air heater in fluid communication with the first air heater to receive heated forced air therefrom includes a heat exchanger for heating forced air introduced thereto to a preheat temperature for combustion in a boiler and thereby cooling flue gas introduced from a boiler to the second air heater to an emission treatment temperature. The second air heater is in fluid communication with the emission treatment system to introduce cooled flue gas thereto.

Abstract: The present invention relates to a process for separating off at least one acidic gas from a gas mixture comprising at least one acidic gas, which comprises the step of contacting of the gas mixture with a porous metal-organic framework, where the framework adsorbs the at least one acidic gas and the framework comprises at least one at least bidentate organic compound coordinated to at least one metal ion, wherein the porous metal-organic framework is impregnated with an amine suitable for a gas scrub. The invention further provides such impregnated metal-organic frameworks.

Abstract: The laughing-gas-containing gas (1) is diluted by means of a diluting gas (2). The diluting gas (2) is virtually free from water fractions in the dryer (3). After feed of the diluting gas (2) via the feed line (13), exhaust gas (8) from the catalytic decomposition (7) is added (4) to the laughing-gas-containing feed gas (12). After addition (4) of the exhaust gas (8) from the catalytic decomposition of laughing gas (7), the laughing-gas-containing feed gas (12) is compressed (5) and passed to the heat exchanger (6). In the heat exchanger (6) the laughing-gas-containing feed gas (12) is preheated by heat exchange with the exhaust gas (8). The exhaust gas (8) is cooled in the heat exchanger (6) in this process. The preheated laughing-gas-containing feed gas (12) is passed via a further optional heater (11) as a feed to the catalytic laughing gas decomposition (7). In order to avoid a concentration build-up, some of the exhaust gas (8) is passed out (9) of the process.

Abstract: Described is a catalyst comprising a substrate and a catalyst coating of two or more layers: (a) a first layer comprising Pd and Rh on the substrate; and (b) a second layer comprising Pt and/or Pd on the first layer; these layers each further comprising: one or more particulate support materials; one or more oxygen storage component (OSC) materials; and one or more nitrogen oxide storage materials comprising one or more elements selected from the group of alkali and/or alkaline earth metals, wherein the total amount of alkali and alkaline earth metals ranges from 0.18 to 2.0 g/in3 calculated as the respective alkali metal oxides M2O and alkaline earth metal oxides MO. Also described is a method for the production of a catalyst, as well as a process for the treatment of a gas stream, in particular of an exhaust gas stream resulting from an internal combustion engine.

Abstract: A method of providing an exhaust treatment device is disclosed. The method includes applying a catalyst including gold and a platinum group metal to a particulate filter. The concentration of the gold and the platinum group metal is sufficient to enable oxidation of carbon monoxide and nitric oxide.

Abstract: First, to decrease an amount of emitted nitrogen oxides to zero as much as possible and also decrease an amount of emitted carbon monoxide to a permissible level. Second, to save energy on combustion at a low air ratio close to 1.0. Third, to attain a stable air ratio control in a low air ratio combustion region.

Abstract: The invention relates to a novel catalyst having excellent activity and selectivity for reducing nitric oxides (NO/NO2) to nitrogen gas (N2) with hydrogen (H2) being used as a reducing agent under strongly oxidizing conditions (e.g., 2-10 vol % O2) (H2-SCR) in the 100-400° C. range, but in particular to the low-temperature range 100-200° C. The inventive catalyst is a combination of platinum and palladium which are in contact with solid phases of a mixed MgO and CeO2 medium.

Abstract: A method of reducing nitrogen oxides (NOx) present in a lean gas stream comprising nitric oxide (NO) comprises the steps of: (i) net adsorbing NO per se from the lean gas stream in an adsorbent comprising palladium and a cerium oxide at below 200° C.; (ii) thermally net desorbing NO from the NO adsorbent in a lean gas stream at 200° C. and above; and (iii) catalytically reducing NOx on a catalyst other than the NO adsorbent with a reductant selected from the group consisting of a hydrocarbon reductant, a nitrogenous reductant, hydrogen and a mixture of any two or more thereof. A system for carrying out such a method is also disclosed.

Abstract: A system for treating a gas stream containing nitrogen oxides (NOx) and particulates flowing in the system comprises means for injecting a source of ammonia (NH3) or urea (CO(NH2)2) into a flowing exhaust gas upstream of a precious metal-free particulate trap, a selective catalytic reduction catalyst disposed downstream of the particulate trap and a source of ammonia or urea.