Abstract: A method of using a catalyst comprises exposing a catalyst to at least one reactant in a chemical process. The catalyst comprises copper and a small pore molecular sieve having a maximum ring size of eight tetrahedral atoms. The chemical process undergoes at least one period of exposure to a reducing atmosphere. The catalyst has an initial activity and the catalyst has a final activity after the at least one period of exposure to the reducing atmosphere. The final activity is within 30% of the initial activity at a temperature between 200 and 500° C.

Abstract: A system for reducing ammonia (NH3) emissions includes (a) a first component comprising a first substrate containing a three-way catalyst, wherein the first component is disposed upstream of a second component comprising a second substrate containing an ammonia oxidation catalyst, wherein said ammonia oxidation catalyst comprises a small pore molecular sieve supporting at least one transition metal; and (b) an oxygen-containing gas input disposed between the components. For example, a CHA Framework Type small pore molecular sieve may be used. A method for reducing NH3 emission includes introducing an oxygen-containing gas into a gas stream to produce an oxygenated gas stream; and exposing the oxygenated gas stream to an NH3 oxidation catalyst to selectively oxidize at least a portion of the NH3 to N2.

Abstract: An article for treating a gas containing nitrogen oxides including: (a) a monolith substrate; and (b) a catalytic composition containing at least one catalytic component consisting of (i) at least one transition metal dispersed on a mixed oxide or composite oxide or a mixture thereof as support material consisting of cerium and zirconium; or (ii) cerium oxide and zirconium oxide as single oxides or a composite oxide thereof or a mixture of the single oxides and the composite oxide dispersed on an inert oxide support material, wherein at least one transition metal is dispersed thereon, provided that at least one selected transition metal is tungsten, wherein the catalytic composition is disposed on the monolith substrate.