Fe-SAPO-34 CATALYST FOR USE IN NOX REDUCTION AND METHOD OF MAKING

Abstract

The system and methods described provide for an Fe-SAPO-34 catalyst in an SCR catalyst for reducing nitrogen oxides (NOx) from vehicle engine exhausts. In one example, the catalyst is formed by incorporating iron during synthesis of the SAPO-34 zeolite, which allows iron to be incorporated into the zeolite crystal lattice structure and eliminates the post-synthesis ion-exchange step. The resulting Fe-SAPO-34 catalyst, which may be used in combination with or in addition to a Cu-CHA catalyst, exhibits good high temperature activity at temperatures above 550° C. and provides for a good thermal stability.

Description

[0001] Cross References to Related Applications [0002] This application requires the U.S. provisional application titled "Fe-SAPO-34 Catalyst for Use in NOx Reduction and Method of Making" filed on February 19, 2014 The priority of Patent Application No. 61 / 941,717 is hereby incorporated by reference in its entirety for all purposes. technical field [0003] This specification relates to the preparation and use of iron zeolite catalysts in the reduction of nitrogen oxides (NOx) from automobile exhaust, and more particularly to Fe-SAPO-34 catalysts useful as SCR catalysts for the reduction of nitrogen oxides. Background technique [0004] In recent years, government regulations in the United States and elsewhere have limited nitrogen oxides (NO x ) emissions. These measures are very important for the development of automobile exhaust systems to promote NO x Reduced catalysts have resulted in increased effort. A number of catalysts are known that convert exhaust gas comp...

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Problems solved by technology

However, incorporation of iron into this catalyst is also difficult using conventional ion-exchange methods due to the small pore openings in the SAPO chabazite structure.

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