NO.sub.x catalyst and method of suppressing sulfate formation in an exhaust purification system
Abstract
The activity and durability of a zeolite lean-burn NOx catalyst can be increased by loading metal cations on the outer surface of the zeolite. However, the metal loadings can also oxidize sulfur dioxide to cause sulfate formation in the exhaust. The present invention is a method of suppressing sulfate formation in an exhaust purification system including a NO.sub.x catalyst. The NO.sub.x catalyst includes a zeolite loaded with at least one metal. The metal is selected from among an alkali metal, an alkaline earth metal, a lanthanide metal, a noble metal, and a transition metal. In order to suppress sulfate formation, at least a portion of the loaded metal is complexed with at least one of sulfate, phosphate, and carbonate.
- Inventors:
-
- Chillicothe, IL
- Peoria, IL
- Issue Date:
- Research Org.:
- Caterpillar Inc., Deerfield, IL (United States)
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 909714
- Patent Number(s):
- 7235221
- Application Number:
- 11/474,584
- Assignee:
- Caterpillar Inc. (Peoria, IL)
- Patent Classifications (CPCs):
-
B - PERFORMING OPERATIONS B01 - PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL B01D - SEPARATION
B - PERFORMING OPERATIONS B01 - PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL B01J - CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY
- DOE Contract Number:
- FC05-97OR22579
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
Citation Formats
Balmer-Millar, Mari Lou, Park, Paul W, and Panov, Alexander G. NO.sub.x catalyst and method of suppressing sulfate formation in an exhaust purification system. United States: N. p., 2007.
Web.
Balmer-Millar, Mari Lou, Park, Paul W, & Panov, Alexander G. NO.sub.x catalyst and method of suppressing sulfate formation in an exhaust purification system. United States.
Balmer-Millar, Mari Lou, Park, Paul W, and Panov, Alexander G. Tue .
"NO.sub.x catalyst and method of suppressing sulfate formation in an exhaust purification system". United States. https://www.osti.gov/servlets/purl/909714.
@article{osti_909714,
title = {NO.sub.x catalyst and method of suppressing sulfate formation in an exhaust purification system},
author = {Balmer-Millar, Mari Lou and Park, Paul W and Panov, Alexander G},
abstractNote = {The activity and durability of a zeolite lean-burn NOx catalyst can be increased by loading metal cations on the outer surface of the zeolite. However, the metal loadings can also oxidize sulfur dioxide to cause sulfate formation in the exhaust. The present invention is a method of suppressing sulfate formation in an exhaust purification system including a NO.sub.x catalyst. The NO.sub.x catalyst includes a zeolite loaded with at least one metal. The metal is selected from among an alkali metal, an alkaline earth metal, a lanthanide metal, a noble metal, and a transition metal. In order to suppress sulfate formation, at least a portion of the loaded metal is complexed with at least one of sulfate, phosphate, and carbonate.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {2007},
month = {6}
}