682 results about "Ternary catalyst" patented technology

A power generation system capable of eliminating NO, components in the exhaust gas by using a 3-way catalyst, comprising a gas compressor to increase the pressure of ambient air fed to the system; a combustor capable of oxidizing a mixture of fuel and compressed air to generate an expanded, high temperature exhaust gas; a gas turbine engine that uses the force of the high temperature gas; an exhaust gas recycle (EGR) stream back to the combustor; a 3-way catalytic reactor downstream of the gas turbine engine outlet which treats the exhaust gas stream to remove substantially all of the NO_x components; a heat recovery steam generator (HRSG); an EGR compressor; and an electrical generator.

Fuel management system for enhanced operation of a spark ignition gasoline engine. Injectors inject an anti-knock agent such as ethanol directly into a cylinder. It is preferred that the direct injection occur after the inlet valve is closed. It is also preferred that stoichiometric operation with a three way catalyst be used to minimize emissions. In addition, it is also preferred that the anti-knock agents have a heat of vaporization per unit of combustion energy that is at least three times that of gasoline.

A high-temperature-resistant fiber layer for an open particulate trap for purifying exhaust gases from mobile internal combustion engines includes metal fibers. At least a section of the fiber layer has a catalytically active and/or adsorbent coating, in particular such as that of an oxidation catalyst and/or a three-way catalyst and/or an SCR catalyst. A longitudinal section, which is substantially perpendicular to a largest outer surface, has openings formed therein with an average size of 0.01 mm to 0.5 mm, in particular 0.05 mm to 0.25 mm. A particulate trap with the coated fiber layer is also provided.

Embodiments are described to improve the durability of a lean NO_x aftertreatment system. According to one embodiment of the present invention an air injection system is used to inject air continuously into the exhaust system between the upstream three-way catalyst and the downstream selective catalytic reduction (SCR) catalyst when the engine is operating at stoichiometric or rich air/fuel ratios and the exhaust temperatures are above a calibratible level (e.g., 700° C.). In another embodiment, an oxidation catalyst is positioned downstream of the air injection point to prevent exothermic reactions from occurring on the SCR. In another embodiment, the reductant for the SCR is generated in-situ. In yet another embodiment, a diverter valve with a reduction catalyst in a bypass arm is utilized to bypass the SCR during high load conditions.

A method for operating a spark-ignition engine having a three-way catalyst and a particulate filter downstream thereof, comprising: oscillating an exhaust air-fuel ratio entering the particulate filter to generate air-fuel ratio oscillations downstream of the particulate filter, while increasing exhaust temperature; when the downstream oscillations are sufficiently dissipated, enleaning the exhaust air-fuel ratio entering the particulate filter; and reducing the enleanment when an exhaust operating parameter is beyond a threshold amount.

The ternary catalyst consists of metal salt, alkyl zinc and glycerine. Glycerine and RE salt in certain ratio are added into selected organic solvent, and under the protection of CO2 and while maintaining the reactant mixture at 25 deg.C, alkyl zinc in calculated amount is dropped. After finishing dropping alkyl zinc, the reactant product is aged in CO2 atmosphere to obtain white ternary catalyst suspension, which is used directly in the copolymerization of CO2 and epoxide to produce aliphatic polycarbonate with number-average molecular weight as high as 50,000 and CO2 fixing rate over 40 wt%.

A multi-phase catalyst for the simultaneous conversion of oxides of nitrogen, carbon monoxide, and hydrocarbons is provided. A catalyst composition comprising the multi-phase catalyst and methods of making the catalyst composition are also provided. The multi-phase catalyst may be represented by the general formula of Ce_yLn_1-xA_x+sMO_Z, wherein Ln is a mixture of elements originally in the form of single-phase mixed lanthanides collected from natural ores, a single lanthanide, or a mixture of lanthanides; A is an element selected from a group consisting of Mg, Ca, Sr, Ba, Li, Na, K, Cs, Rb, or any combination thereof; and M is an element selected from the group consisting of Fe, Mn, Cr, Ni, Co, Cu, V, Zr, Pt, Pd, Rh, Ru, Ag, Au, Al, Ga, Mo, W, Ti, or any combination thereof; x is a number defined by 0≦x<1.0; y is a number defined by 0≦y<10; s is a number defined by 0≦s<10; where s=0 only when y>0 and y=0 only when s>0. The multi-phase catalyst can have an overlayer of an oxide having the fluorite structure with a combination of platinum and/or rhodium.

The invention generally relates to three-way catalysts and catalyst formulations capable of simultaneously converting nitrogen oxides, carbon monoxide, and hydrocarbons into less toxic compounds. Such three-way catalyst formulations contain ZrO₂-based mixed-metal oxide support oxides doped with an amount of lanthanide. Three-way catalyst formulations with the support oxides of the present invention demonstrate higher catalytic activity, efficiency and longevity than comparable catalysts formulated with traditional support oxides.

In a gaseous-fuelled stoichiometric compression ignition internal combustion engine, a pilot fuel is injected directly into the combustion chamber to help initiate a multi-point ignition. The engine provides performance improvements approaching those of high pressure direct injection engines but with less complexity because the gaseous fuel is introduced into the intake air subsystem at relatively low pressure and as a result of the stoichiometric combustion, the low oxygen content in the combustion products exiting the combustion chamber allows the use of a three-way catalyst instead of other after treatment arrangements normally associated with conventional compression ignition engines that require the addition of a reductant.

Systems and methods for controlling regeneration of a particulate filter positioned downstream of an engine in a vehicle are provided herein. One exemplary method includes, during combusting engine conditions, directing exhaust from the engine to a three-way catalyst and then to a particulate filter positioned downstream of the three-way catalyst. The method also includes, during non-combusting engine conditions and while the vehicle is in motion, directing fresh ram-air to the particulate filter to regenerate the particulate filter.

A system for reducing ammonia (NH3) emissions includes (a) a first component comprising a first substrate containing a three-way catalyst, wherein the first component is disposed upstream of a second component comprising a second substrate containing an ammonia oxidation catalyst, wherein said ammonia oxidation catalyst comprises a small pore molecular sieve supporting at least one transition metal; and (b) an oxygen-containing gas input disposed between the components. For example, a CHA Framework Type small pore molecular sieve may be used. A method for reducing NH₃ emission includes introducing an oxygen-containing gas into a gas stream to produce an oxygenated gas stream; and exposing the oxygenated gas stream to an NH₃ oxidation catalyst to selectively oxidize at least a portion of the NH₃ to N₂. The method may further include the step of exposing a rich burn exhaust gas to a three-way catalyst to produce the gas stream comprising NH₃.

A three-element catalyst for cleaning the tail gas of car features that the cellular cordierite ceramics modified by the RE tailing mixture or transition metal oxide is ued as the first carrier, the internal and external modified alumina coating layers are used as the second carrier, and the noble metal Pt, Rh or Pd is used as its active component.

An apparatus of a catalyst for purifying exhaust gas suitable as a three-way catalyst (TWC) apparatus to be used for purifying carbon monoxide (CO), a hydrocarbon (HC) and a nitrogen oxide (NO_x) in exhaust gas exhausted from a gasoline automobile, as well as a method for purifying exhaust gas.

This apparatus is provided by an apparatus of a catalyst for purifying exhaust gas for purifying a hydrocarbon (HC), carbon monoxide (CO) and a nitrogen oxide (NO_x), by providing two or more honeycomb structure-type catalysts, wherein the surface of a honeycomb-type structure is coated with two or more layers of catalyst compositions, in a flow passage of exhaust gas exhausted from an internal combustion engine, and making exhaust gas pass, characterized in that: the honeycomb structure-type catalyst (X) positioned at the upstream side and the honeycomb structure-type catalyst (Y) positioned at the downstream side contain the catalyst composition consisting a support material of an inorganic oxide which substantially does not contain an Rh component, and loads at least one of a Pt component or a Pd component, a cerium-containing oxide, and an alkaline earth metal component, in all of the lower layers; on the other hand, the catalyst composition of the upper layer loads the Rh component on an oxide support material; does not substantially contain the Pt component and the Pd component; and has a configuration which is different in the honeycomb structure-type catalyst (X) and the honeycomb structure-type catalyst (Y).

A method using exhaust gas recirculation (EGR) in an internal combustion engine. The engine has at least one “dedicated EGR cylinder”, whose entire exhaust is recirculated back to all the engine cylinders. The dedicated EGR cylinder is operated at a rich air-fuel ratio, and the other cylinders are operated stoichiometrically so that a conventional three way catalyst may be used to treat the exhaust. A fuel injector is used to inject fuel into the combustion chamber of the dedicated EGR cylinder after initiation of the main combustion event. This post injection method overcomes flammability limits of a dedicated EGR cylinder, and increases the hydrogen (H2) and carbon monoxide (CO) in its exhaust.

An exhaust system (1) is provided with an exhaust passage that allows exhaust gas discharged from an internal combustion engine to pass therethrough, an exhaust emission control unit including a catalyst (2,3) such as a three-way catalyst (27) to purify the exhaust gas, and an exhaust heat collecting unit that converts thermal energy of the exhaust gas into electric energy. The exhaust passage (25) is formed in the center of the exhaust system provided with the exhaust emission control unit. By-pass passages (26) are formed at both sides of the exhaust passage (25) through which the exhaust gas flows without passing through the exhaust emission control unit. The exhaust heat collecting unit (29) is provided on the outer side of each of the by-pass passages (26).

Systems and methods for controlling regeneration of a particulate filter downstream of an engine in a vehicle are provided herein. One exemplary method includes, during an engine shutdown, increasing a throttle opening and regenerating a particulate filter downstream of a three-way catalyst. The method also includes, during an engine start following an engine shutdown, setting one or more engine parameters based on whether the particulate filter was regenerated during a last engine shutdown before the engine start.

A PM sensor for measuring particle matter in exhaust gas is disposed between a three-way catalyst and a muffler in an exhaust pipe, and has an oxidation catalyst and an electrical heater that are stacked together, and a temperature sensor that measures a temperature of the oxidation catalyst interposed between the oxidation catalyst and the electrical heater. The oxidation catalyst carries a ceria as an oxygen-storing agent that occludes oxygen in the exhaust gas, and a ECU calculates a sediment amount of the exhaust particulate matter based on an amount of temperature rise when the electrical heater heats the oxidation catalyst and an accumulated value of an intake air amount.

There is provided a honeycomb catalyst body including, a honeycomb substrate, plugging portions, and a three way catalyst. All the cells are open in the inflow side end face, the honeycomb substrate has two regions of an inflow side region and an outflow side region, the inflow side region of the honeycomb substrate is a region from the inflow side end face to a position of 10 to 90% of a length in an central axial direction of the honeycomb substrate from the inflow side end face, and 100 to 400 g/L of the three way catalyst is loaded on the partition walls in the inflow side region, no catalyst is loaded on the partition walls in the outflow side region, and a ratio of the length to a diameter of the inflow side end face of the honeycomb substrate is 1.1 to 2.0.