Ford Global Technolgoies, LLC

Ford Motor Company Limited

Other

Robert Henry Hammerle

Paul Matthew Laing

Haren S Gandhi

Yisun Cheng

John Vito Cavataio

Karen Marie Adams

Christine Kay Lambert

Ching-Hsong George Wu

William Charles Ruona

Paul Joseph Tennison

Christopher John Mazur

Jeffrey Scott Hepburn

Douglas Allen Dobson

Lifeng Xu

Yisun Chang

This catalyst system simultaneously removes ammonia and enhances net NOx conversion by placing an NH-SCR catalyst formulation downstream of a lean NOx trap. By doing so, the NH-SCR catalyst adsorbs the ammonia from the upstream lean NOx trap generated during the rich pulses. The stored ammonia then reacts with the NOx emitted from the upstream lean NOx trap-enhancing the net NOx conversion rate significantly, while depleting the stored ammonia. By combining the lean NOx trap with the NH-SCR catalyst, the system allows for the reduction or elimination of NHand NOx slip, reduction in NOx spikes and thus an improved net NOx conversion during lean and rich operation.

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According to one aspect of the present invention, a palladium-containing oxidation catalyst is provided. In one embodiment, the palladium-containing oxidation catalyst includes a first zone having a first PGM catalyst loading with a platinum (Pt) to palladium (Pd) weight ratio of no greater than 10.0; and a second zone disposed next to the first zone. In another embodiment, the second PGM catalyst loading has a palladium (Pd) to platinum (Pt) weight ratio of no greater than 4.0.

Palladium-contaning oxidation catalyst

This catalyst system simultaneously removes ammonia and enhances net NO, conversion by placing an NH-SCR catalyst formulation downstream of a lean NOtrap. By doing so, the NH-SCR catalyst adsorbs the ammonia from the upstream lean NOtrap generated during the rich pulses. The stored ammonia then reacts with the NOemitted from the upstream lean NOtrap&#x2014;enhancing the net NOconversion rate significantly, while depleting the stored ammonia. By combining the lean NOtrap with the NH-SCR catalyst, the system allows for the reduction or elimination of NHand NOslip, reduction in NOspikes and thus an improved net NOconversion during lean and rich operation.

This catalyst system simultaneously removes ammonia and enhances net NOx conversion by placing an NH&#x2014;SCR catalyst formulation downstream of a lean NOx trap. By doing so, the NH&#x2014;SCR catalyst adsorbs the ammonia from the upstream lean NOx trap generated during the rich pulses. The stored ammonia then reacts with the NOx emitted from the upstream lean NOx trap-enhancing the net NOx conversion rate significantly, while depleting the stored ammonia. By combining the lean NOx trap with the NH&#x2014;SCR catalyst, the system allows for the reduction or elimination of NHand NOx slip, reduction in NOx spikes and thus an improved net NOx conversion during lean and rich operation.

This catalyst system simultaneously removes ammonia and enhances net NOconversion by placing an NH&#x2014;SCR catalyst formulation downstream of a lean NOtrap. By doing so, the NH&#x2014;SCR catalyst adsorbs the ammonia from the upstream lean NOtrap generated during the rich pulses. The stored ammonia then reacts with the NOemitted from the upstream lean NOtrap&#x2014;enhancing the net NOconversion rate significantly, while depleting the stored ammonia. By combining the lean NOtrap with the NH&#x2014;SCR catalyst, the system allows for the reduction or elimination of NHand NOslip, reduction in NOspikes and thus an improved net NOconversion during lean and rich operation.

This catalyst system simultaneously removes ammonia and enhances net NOx conversion by placing an NH-SCR catalyst formulation downstream of a lean NOx trap. By doing so, the NH-SCR catalyst adsorbs the ammonia from the upstream lean NOx trap generated during the rich pulses. The stored ammonia then reacts with the NOx emitted from the upstream lean NOx trap&#x2014;enhancing the net NOx conversion rate significantly, while depleting the stored ammonia. By combining the lean NOx trap with the NH-SCR catalyst, the system allows for the reduction or elimination of NHand NOx slip, reduction in NOx spikes and thus an improved net NOx conversion during lean and rich operation.

In an apparatus having an internal combustion engine and a catalytic device for treating NOemissions from the internal combustion engine, a method of operating the engine comprising operating the engine for a first interval in such a manner as to store and reduce NOemissions in the catalytic device thereby accumulating stored sulfur in the catalytic device, and operating the engine for a second interval in such a manner as to remove a portion of the stored sulfur from the catalytic device and to leave a substantial portion of stored sulfur in the catalytic device.

System and method for desulfating a NOx trap

A method for controlling reductant injection into an exhaust stream upstream of a catalyst coupled to an internal combustion engine is disclosed. In the method, an ammonia sensor located downstream of the exhaust catalyst is used to determine ammonia concentration in the exhaust stream. The ammonia concentration is compared to an allowable threshold and an allowable fraction, i.e., a maximum limit on a fraction of ammonia in the exhaust stream compared with the ammonia supplied by the reductant injector. Additionally, based on a NOx sensor, it is determined whether NOx conversion of the catalyst has increased in response to an increase in reductant injection. If not, reductant injection quantity is reduced.

Method for adjusting a reductant used in an internal combustion engine to reduce NOx

An automobile exhaust filter that both traps particulates while altering the concentration of one or more gaseous species is provided. This dual functionality is combined in a single device by utilizing a reactive material that simultaneously alters gaseous component concentration while filtering out particulate material. The automobile exhaust filter is suitable for inclusion in the exhaust of a diesel-powered vehicle. A method utilizing the automobile exhaust catalyst is also provided.

Diesel engine after treatment device for conversion of nitrogen oxide and particulate matter

A system for effective NOx and particulate matter control in a diesel or other lean burn internal combustion engine is presented. The system includes a urea-based SCR catalyst having an oxidation catalyst coupled upstream of it and a particulate filter coupled downstream of the SCR catalyst. This system configuration results in improved NOx conversion due to fast SCR catalyst warm-up and higher operating temperatures. Additionally, placing the particulate filter last in this system configuration reduces tailpipe ammonia emissions as well as prevents any thermal damage to the SCR catalyst due to the particulate filter regeneration.

Exhaust gas aftertreatment systems

A system and a method for effective NOx and particulate matter control in a diesel or other lean burn internal combustion engine is presented. The system includes a urea-based SCR catalyst having an oxidation catalyst coupled upstream of it and a particulate filter coupled downstream of the SCR catalyst. The particulate filter regeneration method teaches controlling operating conditions to bring the particulate filter temperature in the range where exothermic reaction between hydrocarbon and oxygen occurs. Once this is accomplished, extra hydrocarbons are injected into the exhaust gas entering the particulate filter where they combust and the resulting exotherm regenerates the filter. This method achieves effective particulate matter control while eliminating the risk of thermal damage to the upstream devices and minimizing regeneration fuel economy penalty.

A system and method for removing NOx from an emission control device is provided. The emission control device is coupled adjacent and downstream of an oxidation catalyst. The method includes adding a reductant to the exhaust gases flowing into the oxidation catalyst. The method further includes partially oxidizing the reductant in the oxidation catalyst to transition a remaining portion of the reductant into a vapor phase. Finally, the method includes oxidizing the remaining portion of the reductant in the emission control device to remove NOx from the device.

System and method for removing NOx from an emission control device

A reductant injection control strategy for controlling an amount of nitrogen oxide reducing agent injected upstream of a selective reduction catalyst uses an ammonia sensor located downstream of the catalyst. An open loop injection quantity is first determined based on operation conditions. Ammonia concentration detected downstream of the catalyst is controlled to a desired value, with the desired value based on catalyst temperature and the open loop injection quantity.

Emission control system with a catalyst

A carbon monoxide sensor placed downstream of the catalytic converter and a temperature sensor placed upstream of the converter in a diesel engine provide information to build a real time CO conversion efficiency versus catalyst temperature curve to determine whether a catalyst has deteriorated beyond a predetermined point with respect to On-Board Diagnostic (OBD) requirements. Pre catalyst CO concentration is inferred from the engine operating conditions, and catalyst temperature is determined using the temperature sensor output and the engine exhaust flow heat transfer model. The real time curve is compared to a reference curve to determine catalyst performance. Catalyst performance with respect to CO conversions can then be correlated to that for HC and NO to meet OBD requirements.

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Franklin, MI, United States of America

Robert Henry Hammerle