Abstract: Bimetallic three-way catalyst devices include a support body, one or more Rh bulk deposits disposed on the support body, and a plurality of Pt atomic clusters disposed on the surface of each of the Rh bulk deposits. Substantially no Pt is deposited on the support body. At least 85% by weight of the Pt atomic clusters comprise up to 10 atoms and the maximum Pt atomic cluster size is 200 Pt atoms. The combined loading of Rh and Pt can be less than 1.5% by weight relative to the weight of the support body. The molar ratio of Rh in a bulk Rh deposit to Pt disposed on the surface of that deposit is at least 5:1.

Abstract: Methods for preparing catalytic systems include passivating a gamma-phase alumina support body to yield a theta-phase alumina support body and applying catalytic metal to passivated theta-phase alumina support body. Passivating can include heating, optionally in the presence of steam. The gamma-phase alumina can be lanthanum-doped gamma-phase alumina and can be about 0.1-55 wt. % lanthanum. The catalytic metal can include rhodium, copper, or nickel. The catalytic metal can be rhodium or nickel, and the catalytic metal can be applied to the passivated theta-phase alumina support body at a loading of about 0.1-10 wt. %. The catalytic metal can be copper, and the catalytic metal can be applied to the passivated theta-phase alumina support body at a loading of about 0.1-30 wt. %. The gamma-phase alumina support body can be at least about 90 wt. % gamma-phase alumina. The passivated theta-phase alumina support body can be at least about 80 wt. % theta-phase alumina.

Abstract: Bimetallic three-way catalyst devices include a support body, one or more Rh bulk deposits disposed on the support body, and a plurality of Pt atomic clusters disposed on the surface of each of the Rh bulk deposits. Substantially no Pt is deposited on the support body. At least 85% by weight of the Pt atomic clusters comprise up to 10 atoms and the maximum Pt atomic cluster size is 200 Pt atoms. The combined loading of Rh and Pt can be less than 1.5% by weight relative to the weight of the support body. The molar ratio of Rh in a bulk Rh deposit to Pt disposed on the surface of that deposit is at least 5:1.

Abstract: Methods for preparing catalytic systems include passivating a gamma-phase alumina support body to yield a theta-phase alumina support body and applying catalytic metal to passivated theta-phase alumina support body. Passivating can include heating, optionally in the presence of steam. The gamma-phase alumina can be lanthanum-doped gamma-phase alumina and can be about 0.1-55 wt. % lanthanum. The catalytic metal can include rhodium, copper, or nickel. The catalytic metal can be rhodium or nickel, and the catalytic metal can be applied to the passivated theta-phase alumina support body at a loading of about 0.1-10 wt. %. The catalytic metal can be copper, and the catalytic metal can be applied to the passivated theta-phase alumina support body at a loading of about 0.1-30 wt. %. The gamma-phase alumina support body can be at least about 90 wt. % gamma-phase alumina. The passivated theta-phase alumina support body can be at least about 80 wt. % theta-phase alumina.

Abstract: The present disclosure provides a method for operating a three-way catalyst system at high temperatures. The method includes passing a high-temperature exhaust stream exiting an engine over a thermally stable three-way catalyst system including a metal oxide support; two or more catalytically active metals disposed on the support; and a porous metal oxide coating disposed on one or more exposed surfaces of the support. At least one of the catalytically active metals may be platinum (Pt). The method further includes reducing an amount of the nitrogen oxides (NOx), carbon monoxide (CO), and non-methane hydrocarbons (HCs) in an effluent stream exiting the thermally stable three-way catalyst system so that the effluent stream has a combined amount of nitrogen oxides (NOx) and non-methane hydrocarbons (HCs) of less than or equal to about 30 mg/mile and less than or equal to about 0.5 g/mile of carbon monoxide (CO).

Abstract: The present disclosure provides a method for operating a three-way catalyst system at high temperatures. The method includes passing a high-temperature exhaust stream exiting an engine over a thermally stable three-way catalyst system including a metal oxide support; two or more catalytically active metals disposed on the support; and a porous metal oxide coating disposed on one or more exposed surfaces of the support. At least one of the catalytically active metals may be platinum (Pt). The method further includes reducing an amount of the nitrogen oxides (NOx), carbon monoxide (CO), and non-methane hydrocarbons (HCs) in an effluent stream exiting the thermally stable three-way catalyst system so that the effluent stream has a combined amount of nitrogen oxides (NOx) and non-methane hydrocarbons (HCs) of less than or equal to about 30 mg/mile and less than or equal to about 0.5 g/mile of carbon monoxide (CO).

Abstract: Technical methods described herein include an emissions control system for treating exhaust gas from an internal combustion engine in a motor vehicle. The emissions control system includes a three-reaction oxygen storage model. The system further includes a three-way catalyst and a controller that controls an oxygen storage level for the three-way catalyst. The controller determines a first reaction rate representing a net rate of cerium oxidation by oxygen, a second reaction rate representing a net rate of cerium reduction by carbon monoxide, and a third reaction rate representing a net rate of cerium reduction by hydrogen. The controller further determines the oxygen storage level based on the first reaction rate, the second reaction rate, and the third reaction rate.

Abstract: A method for monitoring diesel oxidation catalyst function via a brick temperature rise includes pre-storing hydrocarbons on a catalyst coating in a catalyst coated body. A diesel oxidation catalyst (DOC) exhaust treatment device is positioned in an exhaust conduit of a diesel engine. The DOC exhaust treatment device includes the catalyst coated body. A first exhaust gas temperature output defining an inlet gas temperature received in the DOC exhaust treatment device is forwarded to a control module. A time for the inlet gas temperature to reach a target temperature is recorded in the control module. The time for the inlet gas temperature to reach the target temperature is compared in the control module to a time required for a brick temperature of the catalyst coated body to reach the same target temperature.

Abstract: A catalytic converter includes a catalyst. The catalyst includes a non-modified metal oxide support and platinum group metal (PGM) complexes atomically dispersed on the non-modified metal oxide support. The PGM complexes include a PGM species selected from the group consisting of an atom of a platinum group metal, a cluster including from 2 atoms to less than 10 atoms of the platinum group metal, and combinations thereof. An alkali metal or an alkaline earth metal is bonded to the PGM species. The alkali or alkaline earth metal is part of a structure including oxygen atoms and hydrogen atoms.

Abstract: A method of stabilizing a catalyst system includes hydrothermally treating an aluminum oxide catalyst support having ?about 95 volume % of ?-Al2O3 phase by heating to a temperature of about 800° C. to about 1,200° C. in the presence of water. A majority of the ?-Al2O3 is converted to a stable alumina phase selected from the group consisting of: ?-Al2O3, ?-Al2O3, and combinations thereof to form a stabilized porous aluminum oxide support having an average surface area of ?about 50 m2/g to ?about 150 m2/g. A platinum group metal is then bound to a surface of the stable porous aluminum oxide support to form the stabilized catalyst systems.

Abstract: A dual-layer catalyst includes a substrate, a first layer disposed on the substrate, and a second layer disposed on the first layer. The first layer includes a first catalyst for storing NOx when the first catalyst has a temperature below an active temperature of a second catalyst. The first catalyst is to release the stored NOx when the first catalyst is heated to the active temperature of the second catalyst. The second layer includes the second catalyst for ammonia Selective Catalytic Reduction of the released NOx. The dual-layer catalyst is to be included in a catalytic converter and a catalyst system for reducing NOx emissions from a diesel engine, the NOx emissions including NOx emitted during a predetermined cold-start time period.

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) and at 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 catalytic converter includes a catalyst. The catalyst includes a non-modified metal oxide support and platinum group metal (PGM) complexes atomically dispersed on the non-modified metal oxide support. The PGM complexes include a PGM species selected from the group consisting of an atom of a platinum group metal, a cluster including from 2 atoms to less than 10 atoms of the platinum group metal, and combinations thereof. An alkali metal or an alkaline earth metal is bonded to the PGM species. The alkali or alkaline earth metal is part of a structure including oxygen atoms and hydrogen atoms.

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: 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: 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 dual-layer catalyst includes a substrate, a first layer disposed on the substrate, and a second layer disposed on the first layer. The first layer includes a first catalyst for storing NOx when the first catalyst has a temperature below an active temperature of a second catalyst. The first catalyst is to release the stored NOx when the first catalyst is heated to the active temperature of the second catalyst. The second layer includes the second catalyst for ammonia Selective Catalytic Reduction of the released NOx. The dual-layer catalyst is to be included in a catalytic converter and a catalyst system for reducing NOx emissions from a diesel engine, the NOx emissions including NOx emitted during a predetermined cold-start time period.

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: 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 of sizing a light-off core supporting a fixed quantity of a light-off catalyst for an exhaust gas treatment system having an electric heater upstream of the light-off catalyst for heating the exhaust gas includes measuring the cumulative hydrocarbon or carbon monoxide emissions leaving the exhaust gas treatment system for multiple volumetric sizes of the light-off core in accordance with a heating strategy. Alternatively, a model of the treatment system may be used to predict the cumulative hydrocarbon or carbon monoxide emissions. The method further includes selecting the volumetric size of the light-off core that is associated with the lowest cumulative hydrocarbon or carbon monoxide emissions level from the measured or predicted hydrocarbon or carbon monoxide emissions when the exhaust gas is heated in accordance with the heating strategy. The heating strategy may include pre-crank heating, post-crank heating, or a combination of pre-crank heating and post crank heating.