Chemistry of inorganic compounds – Modifying or removing component of normally gaseous mixture – Nitrogen or nitrogenous component
Patent
1992-08-12
1994-06-07
Lewis, Michael
Chemistry of inorganic compounds
Modifying or removing component of normally gaseous mixture
Nitrogen or nitrogenous component
B01D 4700
Patent
active
053187601
ABSTRACT:
A three-way catalyst system for efficiently converting the exhaust gas from a CNG-fueled engine when operated under lean conditions at a redox ratio of 0.02-0.9, the system comprising a first stage catalyst comprising a transition metal-containing zeolite; means for injecting a hydrocarbon into said exhaust gas prior to entry of said exhaust gas into said first stage catalyst, said hydrocarbon having a greater affinity than CH.sub.4 in its ability to react with NO; and a second stage catalyst for treating the effluent from said first stage catalyst and comprising a high surface area alumina impregnated with discontinuous La.sub.2 O.sub.3 and palladium.
The invention also comprehends a method of treating exhaust gases from a lean-burn CNG-fueled engine, operating at a redox ratio of 0.02-0.9; exposing such exhaust gases to a first stage catalyst consisting of copper-ZSM5 zeolite having at least 3% by weight ion-exchange copper; injecting a fast-acting hydrocarbon into said exhaust gas prior to entry of the exhaust gas into said first stage catalyst, the hydrocarbon having a greater affinity than CH.sub.4 in its ability to react with NO; and exposing the effluent from the first stage catalyst to a second stage catalyst comprising palladium supported on alumina containing discontinuous La.sub.2 O.sub.3.
REFERENCES:
patent: 5149511 (1992-09-01), Montreuil et al.
Chattha Mohinder S.
Kudla Robert J.
Subramanian Somasundaram
Dunn Jr. Thomas G.
Ford Motor Company
Lewis Michael
Malleck Joseph W.
May Roger L.
LandOfFree
Exhaust treating system for lean-burn CNG engine does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Exhaust treating system for lean-burn CNG engine, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Exhaust treating system for lean-burn CNG engine will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-791272