Abstract: Disclosed are apparatuses, systems, methods, and devices for generating hydrogen pyrolysis of hydrocarbons (methane, diesel, JP8, etc.) in a reactor. The reactor includes multiple channels in parallel. A hydrocarbon flows in a channel and decomposes into hydrogen and carbon. Hydrogen gas flows out and some of the carbon will deposit on the channel wall. Once carbon deposition reaches a predetermined level, the hydrocarbon flow stops, and air or oxygen is caused to flow into the channels to oxidize carbon into carbon monoxide or carbon dioxide and supply heat to neighboring channels. Simultaneously, the hydrocarbon will flow into neighboring channels causing decomposition into hydrogen and carbon in the neighboring channels. When the carbon coating in the neighboring channels reaches a predetermined level, the gas flow is switched again to air or oxygen. In this way, each channel alternates between decomposing the hydrocarbon and oxidizing the deposited carbon.

Abstract: A process and a plant for cooling a synthesis gas produced by catalytic steam reformation of a hydrocarbonaceous feed gas, which is cooled by heat exchange with boiler feed water for its conversion into steam, by separating the resulting aqueous condensate, wherein the further cooling is effected in that the gas passes through several series-connected cooling stages and comprises the heat exchange with the feed gas, with degassed and non-degassed boiler feed water for generating the steam required for the steam reformation, and with ambient air, and wherein condensate obtained after the last cooling stage is separated from the gas and the gas is discharged for the further treatment, wherein at least after a further cooling stage upstream of the last cooling stage a hot aqueous condensate is separated from the gas.

Abstract: Alloyed Ag/Au nanospheres with high compositional homogeneity ensured by annealing at elevated temperatures show large extinction cross-sections, extremely narrow band-widths and remarkable stability in harsh chemical environments. A critical temperature has been found to be around 930° C., below which the resulting alloy nanospheres, although significantly more stable than pure silver nanoparticles, can still gradually decay upon extended exposure to harsh etchant. The nanospheres annealed above the critical temperature show homogeneous distribution of Ag and Au elements, minimal crystallographic defects, absence of structural and compositional interfaces, which account for the extremely narrow bandwidths of the surface plasmon resonance, and may render many plasmonic applications with high performance and long lifetime, especially for those involving corrosive species.

Abstract: The disclosure relates to an electric exhaust-gas catalytic converter that has a heating device. The heading device includes a first heating element and a second heating element that are arranged separately from one another upstream and downstream of an active catalysis region of the electric exhaust-gas catalytic converter. The disclosure also relates to a vehicle which includes the electric exhaust-gas catalytic converter and to a method for operating the electric exhaust-gas catalytic converter.

Abstract: The present invention involves both separated beds (or physical mixture) and a process for treating a fuel gas comprising sending the fuel gas to a separated bed (or physical mixture), in which the separated beds comprise a first bed of a sulfur sorbent and a second bed of a water gas shift catalyst (a physical mixture of a sulfur sorbent and a water gas shift catalyst). The process comprises first sending the fuel gas to the first bed to remove sulfur compounds from said fuel gas and then the fuel gas goes to the second bed to undergo a water gas shift reaction in which carbon monoxide is converted to carbon dioxide and water is converted to hydrogen. (or sending the fuel gas simultaneously to the physical mixture to remove simultaneously the sulfur compounds and to react CO with water to CO2 and hydrogen).

Abstract: The invention provides a method for oxidizing carbon monoxide present in an oxygen-containing gas phase to carbon dioxide which comprises: adsorbing the carbon monoxide onto porous silica; and irradiating the porous silica with ultraviolet ray. In the invention, mesoporous silica or amorphous silica is used as the porous silica. In particular, silica gel that is amorphous silica is preferably used.

Abstract: The invention relates to a method for controlling a fume treatment center (FTC) (23), scrubbing the baking fumes from a rotary baking furnace (1), in which the fumes are drawn in through at least one suction manifold (11) of the baking furnace (1) and collected in a duct (20, 20?) that conveys said fumes to the fume treatment center (23). The fume treatment center includes a tower (24) which sprays water into the fumes in order to cool same and a least one reactor (25) for the physico-chemical neutralization of the fumes, comprising contact with a reagent powder, such as alumina, followed by filtering (36) of the loaded reagent and the fume dust and recycling in the reactor (25) of at least one fraction of the filtered reagent and mixing of the same with fresh reagent.

Abstract: Hydrogen-producing fuel processing systems, hydrogen purification membranes, hydrogen purification devices, fuel processing and fuel cell systems that include hydrogen purification devices, and methods for operating the same. In some embodiments, operation of the fuel processing system is initiated by heating at least the reforming region of the fuel processing system to at least a selected hydrogen-producing operating temperature. In some embodiments, an electric heater is utilized to perform this initial heating. In some embodiments, use of the electric heater is discontinued after startup, and a burner or other combustion-based heating assembly combusts a fuel to heat at least the hydrogen producing region, such as due to the reforming region utilizing an endothermic catalytic reaction to produce hydrogen gas.

Abstract: Use of physical vapor deposition methodologies to deposit nanoscale gold on activating support media makes the use of catalytically active gold dramatically easier and opens the door to significant improvements associated with developing, making, and using gold-based, catalytic systems. The present invention, therefore, relates to novel features, ingredients, and formulations of gold-based, heterogeneous catalyst systems generally comprising nanoscale gold deposited onto a nanoporous support.

Abstract: Gas Stream Production The present invention provides a method for the production of carbon dioxide and/or hydrogen gas streams, the method comprising: (i) thermally treating a feedstock material to produce a syngas comprising carbon monoxide and hydrogen and plasma-treating the syngas in a plasma treatment unit; (ii) reacting the plasma-treated syngas with water in a further treatment unit, whereby at least some of the carbon monoxide is converted into carbon dioxide; and (iii) recovering hydrogen and/or, separately, carbon dioxide from the syngas.

Abstract: Heterogeneous catalyst systems, methods of making these systems, and methods of using these systems, wherein catalytically active gold is deposited onto composite support media. The composite support media is formed by providing nanoporous material on at least a portion of the surfaces of carbonaceous host material. In representative embodiments, relatively fine, nanoporous guest particles are coated or otherwise provided on surfaces of relatively coarser activated carbon particles. Catalytically active gold may be deposited onto one or both of the guest or host materials either before or after the guest and host materials are combined to from the composite host material. PVD is the preferred catalyst system of depositing gold.

Abstract: A flue gas stream processing system includes a fuel reactor for combusting a fuel to generate a flue gas stream including water vapor, carbon monoxide and carbon dioxide. The system includes an oxidation catalyst downstream of the fuel reactor, the oxidation catalyst configured to receive the flue gas stream and oxidize the carbon monoxide to form a carbon dioxide rich flue gas stream, and a processing unit to liquefy carbon dioxide in the carbon dioxide rich flue gas stream and generate an exhaust gas.

Abstract: The invention relates to a process of the selective oxidation of carbon monoxide to carbon dioxide present in a gas mixture comprising at least one hydrocarbon or a hydrocarbon derivative, and to its integration into a process for producing hydrocarbon derivatives. The process according to the invention comprises a step that consists in bringing said gas mixture into contact with a solid catalyst capable of oxidizing carbon monoxide to carbon dioxide at a chosen temperature, characterized on that said step is carried out in a fluidized bed.

Abstract: Disclosed herein are methods and articles that include a plasmon-resonating nanostructure that employ a photo-thermal mechanism to catalyze the reduction of an oxidant. As such, the plasmon-resonating nanostructure catalyzes a redox reaction at a temperature below a predetermined activation temperature. The method can be efficiently used to catalyze the reduction of an oxidant, for example in a catalytic reactor or in a fuel cell that includes a photon source.

Abstract: The present invention provides for various processes for recovering high purity gaseous hydrogen and high purity gaseous carbon dioxide from the gas stream produced using steam hydrocarbon reforming, especially steam methane reforming, utilizing a H2 pressure swing adsorption unit in combination with either a CO2 pressure swing adsorption unit in combination with a membrane separation unit or a CO2 pressure vacuum swing adsorption unit in combination with a membrane separation unit. The present invention further relates to a process for optimizing the recovery of carbon dioxide from waste gas streams produced during the hydrogen purification step of a steam hydrocarbon reforming/water gas shift reactor/H2 pressure swing adsorption unit utilizing either a CO2 pressure swing adsorption unit in combination with a membrane separation unit or a CO2 pressure vacuum swing adsorption unit in combination with a membrane separation unit.

Abstract: Use of physical vapor deposition methodologies to deposit nanoscale gold on activating support media makes the use of catalytically active gold dramatically easier and opens the door to significant improvements associated with developing, making, and using gold-based, catalytic systems. The present invention, therefore, relates to novel features, ingredients, and formulations of gold-based, heterogeneous catalyst systems generally comprising nanoscale gold deposited onto a nanoporous support.

Abstract: Heterogeneous catalyst systems, methods of making these systems, and methods of using these systems, wherein catalytically active gold is deposited onto composite support media. The composite support media is formed by providing nanoporous material on at least a portion of the surfaces of carbonaceous host material. In representative embodiments, relatively fine, nanoporous guest particles are coated or otherwise provided on surfaces of relatively coarser activated carbon particles. Catalytically active gold may be deposited onto one or both of the guest or host materials either before or after the guest and host materials are combined to from the composite host material. PVD is the preferred catalyst system of depositing gold.

Abstract: Use of physical vapor deposition methodologies to deposit nanoscale gold on activating support media makes the use of catalytically active gold dramatically easier and opens the door to significant improvements associated with developing, making, and using gold-based, catalytic systems. The present invention, therefore, relates to novel features, ingredients, and formulations of gold-based, heterogeneous catalyst systems generally comprising nanoscale gold deposited onto a nanoporous support.

Abstract: Heterogeneous catalyst systems, methods of making these systems, and methods of using these systems, wherein catalytically active gold is deposited onto composite support media. The composite support media is formed by providing nanoporous material on at least a portion of the surfaces of carbonaceous host material. In representative embodiments, relatively fine, nanoporous guest particles are coated or otherwise provided on surfaces of relatively coarser activated carbon particles. Catalytically active gold may be deposited onto one or both of the guest or host materials either before or after the guest and host materials are combined to from the composite host material. PVD is the preferred catalyst system of depositing gold.

Abstract: Systems and methods for contacting a liquid, gas, and/or a multi-phase mixture with particulate solids. The system can include a body having a first head and a second head disposed thereon. Two or more discrete fixed beds can be disposed across a cross-section of the body. One or more unobstructed fluid flow paths can bypass each fixed bed, and one or more baffles can be disposed between the fixed beds.

Abstract: Systems and methods for contacting a liquid, gas, and/or a multi-phase mixture with particulate solids. The system can include a body having a first head and a second head disposed thereon. Two or more discrete fixed beds can be disposed across a cross-section of the body. One or more unobstructed fluid flow paths can bypass each fixed bed, and one or more baffles can be disposed between the fixed beds.

Abstract: Hydrogen-producing fuel processing systems, hydrogen purification membranes, hydrogen purification devices, fuel processing and fuel cell systems that include hydrogen purification devices, and methods for operating the same. In some embodiments, operation of the fuel processing system is initiated by heating at least the reforming region of the fuel processing system to at least a selected hydrogen-producing operating temperature. In some embodiments, an electric heater is utilized to perform this initial heating. In some embodiments, use of the electric heater is discontinued after startup, and a burner or other combustion-based heating assembly combusts a fuel to heat at least the hydrogen producing region, such as due to the reforming region utilizing an endothermic catalytic reaction to produce hydrogen gas.

Abstract: Carbon monoxide is removed from material streams by adsorption to an adsorption composition comprising oxides of copper, zinc and aluminum, the copper-comprising fraction of which has a degree of reduction, expressed as weight ratio of metallic copper to the sum of metallic copper and copper oxides, calculated as CuO, of at most 60%.

Abstract: A method of carbon monoxide (CO) removal comprises providing an oxidation catalyst comprising cobalt supported on an inorganic oxide. The method further comprises feeding a gaseous stream comprising CO, and oxygen (O2) to the catalyst system, and removing CO from the gaseous stream by oxidizing the CO to carbon dioxide (CO2) in the presence of the oxidation catalyst at a temperature between about 20 to about 200° C.

Abstract: Systems and methods for contacting a liquid, gas, and/or a multi-phase mixture with particulate solids. The system can include a body having a first head and a second head disposed thereon. Two or more discrete fixed beds can be disposed across a cross-section of the body. One or more unobstructed fluid flow paths can bypass each fixed bed, and one or more baffles can be disposed between the fixed beds.

Abstract: Processes for the catalytic conversion of a carbonaceous composition into a gas stream comprising methane are provided, where a sour shift reaction is used to remove carbon monoxide gas stream produced by the gasification process. The incorporation of the sour shift reaction provides an efficient and cost-effective means of eliminating carbon monoxide from the gas stream. In addition, the sour shift reaction also generates additional hydrogen, thus increasing the amount of hydrogen produced from the gasification process.

Abstract: The present invention relates to a highly active water gas shift catalyst and a process for producing it, and also a process for converting a gas mixture comprising at least carbon monoxide and water into hydrogen and carbon dioxide in a wide temperature range using this catalyst.

Abstract: A method for the synthesis of anhydrous hydrogen halide fluids from organic halide fluids, such as perfluorocarbon fluids and refrigerant fluids, and anhydrous carbon dioxide for the environmentally safe disposition thereof.

Abstract: Carbon monoxide (CO) may be removed from flue gas generated by oxyfuel combustion of a hydrocarbon or carbonaceous fuel, by contacting the flue gas, or a CO-containing gas derived therefrom, at a first elevated temperature, e.g. at least 80° C., and at a first elevated pressure, e.g. at least 2 bar (0.2 MPa), with at least one catalyst bed comprising a CO-oxidation catalyst in the presence of oxygen (O2) to convert CO to carbon dioxide and produce carbon dioxide-enriched gas. The carbon dioxide produced from the CO may be recovered from the carbon dioxide-enriched gas using conventional carbon dioxide recovery techniques. NO in the flue gas may also be oxidized to nitrogen dioxide (NO2) and removed using conventional NO2 removal techniques, or may be reduced in the presence of a reducing gas to nitrogen (N2) which does not have to be removed from the gas.

Abstract: The present invention provides a catalyst precursor substance containing copper, zinc, and aluminum and exhibiting an X-ray diffraction pattern having a broad peak at a specific interplanar spacing d (?). The present invention also provides a method for producing the catalyst precursor substance by mixing a solution containing a copper salt, a zinc salt, and an aluminum salt with a solution containing an alkali metal hydroxide or an alkaline earth metal hydroxide, thereby forming a precipitate. In the present invention, a catalyst is prepared through calcining of the catalyst precursor; the catalyst is employed for water gas shift reaction; and carbon monoxide conversion is carried out by use of the catalyst.

Abstract: A method for oxidizing an amount of CO in a CO-containing gas stream, e.g., a combustion stream from fuel combustion, is provided. The method comprises exposing the CO-containing gas stream to a catalytic coating at reaction conditions, including at least 8 vol. % O2 and a temperature of at least 600° C. At these reaction conditions, the method comprises generating gaseous intermediate oxidizing species at the catalytic coating for oxidation of the carbon monoxide within the CO-containing gas stream as a homogeneous reaction to improve CO removal efficiency.

Abstract: Use of physical vapor deposition methodologies to deposit nanoscale gold on activating support media makes the use of catalytically active gold dramatically easier and opens the door to significant improvements associated with developing, making, and using gold-based, catalytic systems. The present invention, therefore, relates to novel features, ingredients, and formulations of gold-based, heterogeneous catalyst systems generally comprising nanoscale gold deposited onto a nanoporous support.

Abstract: The invention described herein relates to a novel process that eliminates the need for post combustion CO2 capture from fired heaters (at atmospheric pressure and in dilute phase) in a petroleum refinery to achieve environmental targets by capturing CO2 in a centralized facility and providing fuel gas low in carbon to the fired heaters. It combines the pre-combustion capture of carbon dioxide with production of a hydrogen fuel source within a refinery to drastically reduce the carbon dioxide emissions of the plant. The hydrogen fuel is utilized for the process fired heaters and the fuel quality (carbon content) can be set to meet the refinery's emissions objectives. Moreover, the carbon dioxide captured can be sequestered and/or utilized for enhanced oil recovery (EOR).

Abstract: Heterogeneous catalyst systems, methods of making these systems, and methods of using these systems, wherein catalytically active gold is deposited onto composite support media. The composite support media is formed by providing nanoporous material on at least a portion of the surfaces of carbonaceous host material. In representative embodiments, relatively fine, nanoporous guest particles are coated or otherwise provided on surfaces of relatively coarser activated carbon particles. Catalytically active gold may be deposited onto one or both of the guest or host materials either before or after the guest and host materials are combined to from the composite host material. PVD is the preferred catalyst system of depositing gold.

Abstract: The disclosed subject matter is directed to a method for producing nanoparticles, as well as the nanoparticles produced by this method. In one embodiment, the nanoparticles produced by the disclosed method have a high defect density. A solution including cerium nitrate hexahydrate is combined with a solution including hexamethylenetetramine to form a combined aqueous solution. After a period of time, the combined aqueous solution is combined with a solution including copper nitrate trihydrate to form a further aqueous solution. The further aqueous solution is then mixed to produce nanoparticles.

Abstract: The present invention provides a core-shell nanoparticle that includes a metal-oxide shell and a nanoparticle. Pores extend from an outer surface to an inner surface of the shell. The inner surface of the shell forms a void, which is filled by the nanoparticle. The pores allow gas to transfer from outside the shell to a surface of the nanoparticle. The present invention also provides a method of making a core-shell nanoparticle includes forming a metal-oxide shell on a colloidal nanoparticle, which forms a precursor core-shell nanoparticle. A capping agent is removed from the precursor core-shell nanoparticle, which produces the core-shell nanoparticle. The present invention also provides a method of using a nanocatalyst of the present invention includes providing the nanocatalyst, which is the core-shell nanoparticle. Reactants are introduced in a vicinity of the nanocatalyst, which produces a reaction that is facilitated or enhanced by the nanocatalyst.

Abstract: A flue gas stream processing system includes a fuel reactor for combusting a fuel to generate a flue gas stream including water vapor, carbon monoxide and carbon dioxide. The system includes an oxidation catalyst downstream of the fuel reactor, the oxidation catalyst configured to receive the flue gas stream and oxidize the carbon monoxide to form a carbon dioxide rich flue gas stream, and a processing unit to liquefy carbon dioxide in the carbon dioxide rich flue gas stream and generate an exhaust gas.

Abstract: The present invention relates to a method of making a chemical compound comprising nickel, aluminum, oxygen and sulfur having a general formula Ni2xAl2O2x+3?zSz, wherein 0.5?x?3 and 0?z?2x. The material is effective for the removal of S-compounds from gaseous streams, effective for catalyzing a water gas shift reaction and suppresses the formation of carbon monoxide and hydrogen under conditions where a water gas shift reaction is catalyzed.

Abstract: Methods of making supported monolithic gold (Au) catalysts that can be used for generating a hydrogen-rich gas from gas mixtures containing carbon monoxide, hydrogen and water via a water gas shift reaction, and for the removal of carbon monoxide from air at a low reaction temperature via its oxidation reaction are described. Methods of making highly dispersed gold catalysts on washcoated monoliths and the stabilization of monolithic catalyst supports by the addition of a third metal oxide, such as zirconia (ZrO2), lanthanum oxide (La2O3), or manganese oxide (MnxOy). The catalyst supports and/or washcoats may include a variety of transition metal oxides such as alpha iron oxide (?-Fe2O3), cerium oxide (CeO2), ZrO2, gamma alumina (?-Al2O3), or their combinations.

Abstract: Use of physical vapor deposition methodologies to deposit nanoscale gold on activating support media makes the use of catalytically active gold dramatically easier and opens the door to significant improvements associated with developing, making, and using gold-based, catalytic systems. The present invention, therefore, relates to novel features, ingredients, and formulations of gold-based, heterogeneous catalyst systems generally comprising nanoscale gold deposited onto a nanoporous support.

Abstract: In operating the carbon monoxide removal reactor or the fuel reforming system, there is provided a technique for removing carbon monoxide in a stable manner for an extended period of time. In a method of removing carbon monoxide including an introducing step of introducing a reactant gas including mixture gas and an oxidizer added thereto to a carbon monoxide removal reactor forming in its casing a catalyst layer comprising a carbon monoxide removal catalyst for removing carbon monoxide contained in the mixture gas and a removing step of removing the carbon monoxide by causing the oxidizer to react with the mixture gas on the carbon monoxide removal catalyst, in said introducing step, the reactant gas of 100° C. or lower is introduced to the carbon monoxide removal reactor.

Abstract: This invention describes a new hydrogen purification process that employs a combination of at least three membrane separation units. This process allows non-stationary operations and is particularly suitable for the production of hydrogen for the purpose of its use in a fuel cell.

Abstract: The present invention relates to a method for oxidizing CO, comprising: passing a first feed comprising CO and a second feed comprising oxygen, in an oxidation zone, over a catalyst comprising highly dispersed gold on sulfated zirconia, at oxidation conditions, to produce an effluent comprising a lower level of CO than in the first feed.

Abstract: A durable catalyst support/catalyst is capable of extended water gas shift operation under conditions of high temperature, pressure, and sulfur levels. The support is a homogeneous, nanocrystalline, mixed metal oxide of at least three metals, the first being cerium, the second being Zr, and/or Hf, and the third importantly being Ti, the three metals comprising at least 80% of the metal constituents of the mixed metal oxide and the Ti being present in a range of 5% to 45% by metals-only atomic percent of the mixed metal oxide. The mixed metal oxide has an average crystallite size less than 6 nm and forms a skeletal structure with pores whose diameters are in the range of 4-9 nm and normally greater than the average crystallite size. The surface area of the skeletal structure per volume of the material of the structure is greater than about 240 m2/cm3. The method of making and use are also described.

Abstract: A system and process for maximizing the generation of electrical power from a variety of hydrocarbon feedstocks. The hydrocarbon feedstocks are first gasified and then oxidized in a two-chamber system and process using oxygen gas rather than ambient air. Intermediate gases generated in the system and process are recirculated and recycled to the gasification and oxidation chambers in order to maximize energy production. The energy produced through the system and process is used to generate steam and produce power through conventional steam turbine technology. In addition to the release of heat energy, the hydrocarbon feedstocks are oxidized to the pure product compounds of water and carbon dioxide, which are subsequently purified and marketed. The system and process minimizes environmental emissions.

Abstract: A method of reducing the amount of carbon monoxide in process fuel gas in a feed stream for a fuel cell. The method includes introducing a hydrocarbon feed stream into a primary reactor and reacting the hydrocarbon feed stream in effective contact with a reforming catalyst forming primary reactor products containing hydrogen, carbon monoxide, carbon dioxide, and methane; placing a high activity water gas shift catalyst system into a water gas shift converter, introducing the primary reactor products into the water gas shift converter in effective contact with the high activity water gas shift catalyst system, and reacting the carbon monoxide and water to form carbon dioxide and hydrogen using a water gas shift reaction forming the feed stream for the fuel cell; and introducing the feed stream into the fuel cell. The high water gas shift catalyst system includes a noble metal, a support comprising a mixed metal oxide of cerium oxide and at least one of zirconium oxide or lanthanum oxide.

Abstract: The invention relates to a process for preparing Cu/Zn/Al catalysts. In this process, the metals are used in the form of their formates and are precipitated in a suitable form. Suitable precipitants are, for example, alkali metal carbonates. The invention further relates to a catalyst as can be obtained by the process according to the invention and to its use.

Abstract: The present invention involves a process and materials for simultaneous desulfurization and water gas shift of a gaseous stream comprising contacting the gas stream with a nickel aluminate catalyst. The nickel aluminate catalyst is preferably selected from the group consisting of Ni2xAl2O2x+3, Ni(2?y)Ni0yAl2O(5?y), Ni(4?y)Ni0yAl2O(7?y), Ni(6?y)Ni0yAl2O(9?y), and intermediates thereof, wherein x?0.5 and 0.01?y?2. Preferably, x is between 1 and 3. More preferably, the nickel containing compound further comprises Ni2xAl2O2x+3?zSz wherein 0?z?2x.

Abstract: Hopcalite-type catalysts for oxidation of CO are formed by preparing a mixed-metal oxide precursor by firstly preparing a solution of a mixture of metal precursor compounds in a solvent, followed by contacting the solution with a supercritical antisolvent to precipitate the mixed-metal oxide precursor. A mixed-metal oxide may then be prepared from the precursor by oxidation, for example by calcination. The mixed-metal oxide is then collected and optionally activated for use as a catalyst. The activated or calcined catalyst contains a nano-structured mixed-phase composition comprising phase-separated intimately mixed nanoparticles of copper and manganese oxide.

Abstract: A component of a cigarette comprises a silver-based catalyst for the conversion of carbon monoxide to carbon dioxide. The silver-based catalyst comprises particles (e.g., nanoscale or larger sized particles) of metallic silver and/or silver oxide supported in and/or on metal oxide support particles. The silver-based catalyst can be incorporated into a cigarette component such as tobacco cut filler, cigarette paper and cigarette filter material to reduce the concentration of carbon monoxide in the mainstream smoke of a cigarette during smoking. The catalyst can also be used in non-cigarette applications.