06171556 is referenced by 110 patents and cites 58 patents.

A method and apparatus in accordance with the invention is described which comprises treating an engine exhaust gas stream containing hydrocarbons and other pollutants. The method of this invention comprises the steps of flowing the exhaust gas stream through a catalytic member comprising a monolith body having a first catalyst zone and a second catalyst zone therein to contact a catalyst in a first catalyst zone to convert at least some of the pollutants in the exhaust gas stream into innocuous products. The exhaust gas stream is then discharged from the catalytic member and flowed through an adsorbent zone to adsorb at least some of the hydrocarbon pollutants with an adsorbent composition. The exhaust gas stream is then discharged from the adsorbent zone and flowed to the second catalyst zone to convert at least some of the pollutants into innocuous products. The exhaust gas stream, so treated, is then discharged to the atmosphere through suitable discharge means. A preferred adsorbent is a zeolite, having a relatively high silica to alumina ratio and a low relative Bronsted acidity. The preferred adsorbent compositions comprise Beta zeolites. An oxidant such as air may be added to the exhaust gas stream at a point upstream of the second catalyst zone.

Title
Method and apparatus for treating an engine exhaust gas stream
Application Number
8/154808
Publication Number
6171556 (B2)
Application Date
November 19, 1993
Publication Date
January 9, 2001
Inventor
Samuel Jack Tauster
Englishtown
NJ, US
John Joseph Steger
Pittstown
NJ, US
Ronald Marshall Heck
Frenchtown
NJ, US
Joseph Charles Dettling
Howell
NJ, US
John Karl Hochmuth
Bridgewater
NJ, US
Patrick Lee Burk
Freehold
NJ, US
Agent
Richard A Negin
US
Assignee
Engelhard Corporation
NJ, US
IPC
F01N 3/28
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