Abstract: A catalytic converter includes a catalyst. The catalyst includes a support, platinum group metal (PGM) particles dispersed on the support, and a barrier formed on the support. The barrier is disposed between a first set of the PGM particles and a second set of the PGM particles to suppress aging of the PGM particles.

Abstract: A method for controlling a vehicle including an exhaust aftertreatment system for purifying exhaust gases from a compression-ignition engine includes monitoring vehicle operating parameters, determining whether the vehicle is stopped, determining whether the engine is commanded off, and determining whether the exhaust aftertreatment device is at a predetermined operating temperature. When the vehicle is stopped, the engine is commanded off and the exhaust aftertreatment device is at the predetermined operating temperature the engine is controlled in a run-on state for a predetermined period of time. The run-on state includes operating the engine in a throttled and fueled state.

Abstract: The present technology relates to perovskite materials for oxygen storage. In one aspect, the perovskite material includes at least one platinum group metal (PGM) andat least one perovskite compound selected from the group consisting of formula (a): LaxMO3 and formula (b): La(1-y)SryMO3, wherein: M is selected from the group consisting of Co, Cu, Fe, Mn and Ni; x is about 0.7 to about 1.1; and y is 0 to about 0.8, and wherein M, x, and y are independently variable for each one of said perovskite compounds. In one exemplary method, the perovskite materials of the technology are employed to treat automotive exhaust gas. In one embodiment, the perovskite materials are included in the washcoat of an automotive catalytic converter.

Abstract: A method for removing NOX from an oxygen-rich exhaust flow produced by a combustion source that is combusting a lean mixture of air and fuel may include passing the oxygen-rich exhaust flow through an exhaust aftertreatment system that includes a NOX oxidation catalyst that includes perovskite oxide particles, a NOX storage catalyst, and a NOX reduction catalyst.

Abstract: An exhaust aftertreatment system for purifying exhaust gases from a compression-ignition engine includes a first exhaust aftertreatment device including an oxidation catalyst and a particulate filter element fluidly coupled to an exhaust outlet of the engine. A second exhaust aftertreatment device includes an ammonia-selective catalytic reduction catalyst fluidly coupled to a downstream outlet of the first exhaust aftertreatment device. A reductant injection system is configured to inject urea reductant into the exhaust gas feedstream between the first exhaust aftertreatment device and the second exhaust aftertreatment device.

Abstract: A method for controlling a vehicle including an exhaust aftertreatment system for purifying exhaust gases from a compression-ignition engine includes monitoring vehicle operating parameters, determining whether the vehicle is stopped, determining whether the engine is commanded off, and determining whether the exhaust aftertreatment device is at a predetermined operating temperature. When the vehicle is stopped, the engine is commanded off and the exhaust aftertreatment device is at the predetermined operating temperature the engine is controlled in a run-on state for a predetermined period of time. The run-on state includes operating the engine in a throttled and fueled state.

Abstract: Catalysts that are resistant to high-temperature sintering and methods for preparing such catalysts that are resistant to sintering at high temperatures are provided. The catalysts include a metal nanoparticle bound to a metal oxide support, where the metal nanoparticle and support are coated with a porous metal oxide coating layer. The catalyst is prepared by contacting a metal nanoparticle bound to a metal oxide support with a solution of metal salts, drying the solution of metal salts, and calcining the metal salts to generate a porous metal oxide coating on the metal nanoparticle and metal oxide support.

Abstract: In an example of a method for suppressing aging of platinum group metal (PGM) particles in a catalytic converter, PGM particles are applied to a support. A surface of the PGM particles is passivated by exposing the PGM particles to carbon monoxide at a temperature equal to or less than 200° C. to introduce —CO groups to the surface. Atomic layer deposition (ALD) is performed to selectively grow a barrier on the support around the PGM particles.

Abstract: A catalytic converter includes a catalyst. The catalyst includes a support, platinum group metal (PGM) particles dispersed on the support, and a barrier formed on the support. The barrier is disposed between a first set of the PGM particles and a second set of the PGM particles to suppress aging of the PGM particles.

Abstract: In an example of a method for forming a catalyst, a polymeric solution including a platinum group metal (PGM) is exposed to electrospinning to form carbon-based nanofibers containing PGM nanoparticles therein. An outer surface of the carbon-based nanofibers containing the PGM nanoparticles is coated with a metal oxide or a metal oxide precursor. The carbon-based nanofibers are selectively removed to form metal oxide nanotubes having PGM nanoparticles retained within a hollow portion thereof.

Abstract: A catalytic converter includes a catalyst. The catalyst includes a supporting oxide layer. The catalyst also includes platinum group metal (PGM) particles partially embedded in the supporting oxide layer such that a portion of each PGM particle is surrounded by the supporting oxide layer and an other portion of each PGM particle remains exposed.

Abstract: An example of a catalytic converter includes a catalyst to improve low temperature oxidation of carbon monoxide (CO) and hydrocarbons. The catalyst includes a support, which includes a porous alumina structure and a rare earth metal oxide promoter impregnated into pores of the porous alumina structure. The rare earth metal oxide promoter is selected from the group consisting of CeO2 and CeO2—ZrO2. A platinum group metal (PGM) is bonded to the support.

Abstract: An aftertreatment system utilizes chemical reactions to treat an exhaust gas flow. A device for use within an aftertreatment system includes a silver-based NOx storage catalyst and a zeolite. The silver-based NOx storage catalyst and the zeolite store NOx through a low temperature startup period of operation. In one embodiment, the zeolite includes a barium Y zeolite.

Abstract: A Cu-amine complex of hydrated copper sulfate and ethylene diamine or an oligomer of ethylene diamine is employed in a direct (one-pot) synthesis of a copper-cation containing silicoaluminophosphate (SAPO) zeolite material having the Cu/SAPO-34 structure. The copper-amine complex is included in an aqueous gel of precursors of the SiO2, Al2O3, and P2O5 constituents, which are mixed, aged, and thermally treated to form the desired Cu/SAPO-34 structure. The synthesized Cu/SAPO-34 material is demonstrated to be an effective catalyst material in conversion of nitric oxide to nitrogen (using ammonia as a reductant) in synthetic exhaust streams characteristic of diesel engine and other lean-burn vehicle engine exhaust streams.

Abstract: Nitrogen oxides (NOx), carbon monoxide (CO), and residual hydrocarbons are adsorbed and stored from a low temperature, cold-start, diesel engine (or lean-burn gasoline engine) exhaust stream by a combination of a silver-based (Ag/Al2O3) NOx adsorber material and a zeolite-platinum group metal (zeolite-PGM) adsorber material for low temperature temporary storage of the NOx. The combination of NOx adsorber materials is formed as separate washcoats on channel walls of an extruded flow-through monolithic support.

Abstract: An aftertreatment system utilizes chemical reactions to treat an exhaust gas flow. A device for use within an aftertreatment system includes a silver-based NOx storage catalyst and a zeolite. The silver-based NOx storage catalyst and the zeolite store NOx through a low temperature startup period of operation. In one embodiment, the zeolite includes a barium Y zeolite.

Abstract: An aftertreatment system utilizes chemical reactions to treat an exhaust gas flow. A system for aftertreatment of the exhaust gas flow includes a NOx sensor configured to monitor within the exhaust gas flow one of a lambda value and a NOx concentration value and a computerized processor device configured to calibrate the monitored value for presence of one of NH3, H2, and hydrocarbons. In one embodiment, the system further includes a pair of NOx sensors, each monitoring both a lambda value and a NOx concentration value. In another embodiment, the system controls the aftertreatment based upon the calibrated values.

Abstract: An aftertreatment system utilizes chemical reactions to treat an exhaust gas flow. A device for use within an aftertreatment system includes a platinum-free ammonia oxidation catalyst comprising palladium to treat ammonia slip in the exhaust gas flow. In one embodiment, the catalyst includes a Pd/Cu/SAPO-34 catalyst used within a selective catalytic reduction device or in a device downstream of the selective catalytic reduction device.

Abstract: An exhaust treatment system comprises a filter device in communication with the engine and configured to receive exhaust gas therefrom. The filter device comprises a canister including an inlet, a filter structure having an upstream, inlet end, a downstream, outlet end, and a series of filtering flow passages. A center zone conduit is in sealing, fluid contact with the downstream, outlet end of the filter structure to thereby define a center flow zone and perimeter flow zone. A flow control valve assembly is disposed in the center zone conduit. A controller is in signal communication with the flow control valve and a temperature sensor and monitors a temperature profile of the filter structure wherein, upon a determination that the temperature of the center flow zone of the filter structure is above a predetermined level, the controller drives the flow control valve assembly to a closed position.

Abstract: An exhaust aftertreatment system for purifying exhaust gases from a compression-ignition engine includes a first exhaust aftertreatment device including an oxidation catalyst and a particulate filter element fluidly coupled to an exhaust outlet of the engine. A second exhaust aftertreatment device includes an ammonia-selective catalytic reduction catalyst fluidly coupled to a downstream outlet of the first exhaust aftertreatment device. A reductant injection system is configured to inject urea reductant into the exhaust gas feedstream between the first exhaust aftertreatment device and the second exhaust aftertreatment device.