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Title: NOx adsorber and method of regenerating same

Abstract

New technologies, such as NOx adsorber catalytic converters, are being used to meet increasingly stringent regulations on undesirable emissions, including NOx emissions. NOx adsorbers must be periodically regenerated, which requires an increased fuel consumption. The present disclosure includes a method of regenerating a NOx adsorber within a NOx adsorber catalytic converter. At least one sensor positioned downstream from the NOx adsorber senses, in the downstream exhaust, at least one of NOx, nitrous oxide and ammonia concentrations a plurality of times during a regeneration phase. The sensor is in communication with an electronic control module that includes a regeneration monitoring algorithm operable to end the regeneration phase when a time rate of change of the at least one of NOx, nitrous oxide and ammonia concentrations is after an expected plateau region begins.

Inventors:
 [1];  [2];  [3]
  1. Peoria, IL
  2. Metamora, IL
  3. Dunlap, IL
Publication Date:
Research Org.:
Caterpillar Inc (Peoria, IL)
Sponsoring Org.:
USDOE
OSTI Identifier:
902919
Patent Number(s):
7,168,243
Application Number:
11/074,402
Assignee:
Caterpillar Inc (Peoria, IL) OSTI
DOE Contract Number:
FC05-00OR22806
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Endicott, Dennis L, Verkiel, Maarten, and Driscoll, James J. NOx adsorber and method of regenerating same. United States: N. p., 2007. Web.
Endicott, Dennis L, Verkiel, Maarten, & Driscoll, James J. NOx adsorber and method of regenerating same. United States.
Endicott, Dennis L, Verkiel, Maarten, and Driscoll, James J. Tue . "NOx adsorber and method of regenerating same". United States. doi:. https://www.osti.gov/servlets/purl/902919.
@article{osti_902919,
title = {NOx adsorber and method of regenerating same},
author = {Endicott, Dennis L and Verkiel, Maarten and Driscoll, James J},
abstractNote = {New technologies, such as NOx adsorber catalytic converters, are being used to meet increasingly stringent regulations on undesirable emissions, including NOx emissions. NOx adsorbers must be periodically regenerated, which requires an increased fuel consumption. The present disclosure includes a method of regenerating a NOx adsorber within a NOx adsorber catalytic converter. At least one sensor positioned downstream from the NOx adsorber senses, in the downstream exhaust, at least one of NOx, nitrous oxide and ammonia concentrations a plurality of times during a regeneration phase. The sensor is in communication with an electronic control module that includes a regeneration monitoring algorithm operable to end the regeneration phase when a time rate of change of the at least one of NOx, nitrous oxide and ammonia concentrations is after an expected plateau region begins.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Jan 30 00:00:00 EST 2007},
month = {Tue Jan 30 00:00:00 EST 2007}
}

Patent:

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