Certain selective catalytic reduction (SCR) articles, systems and methods provide for high NOx conversion while at the same time low N.sub.2O formation. The articles, systems and methods are suitable for instance for the treatment of exhaust gas of diesel engines. Certain articles have zoned coatings containing copper-containing molecular sieves disposed thereon, where for example a concentration of catalytic copper in an upstream zone is lower than the concentration of catalytic copper in a downstream zone.

The invention relates to a catalyst comprising a small-pore zeolite that contains iron and copper and has a maximum ring size of eight tetrahedral atoms, characterized in that the channel width of the small-pore zeolite amounts to >3.8 (0.38 nm) in at least one dimension.

The invention relates to a catalyst comprising a small-pore zeolite that contains iron and copper and has a maximum ring size of eight tetrahedral atoms, characterized in that the channel width of the small-pore zeolite amounts to >3.8 (0.38 nm) in at least one dimension.

The present disclosure generally provides catalysts, catalyst articles and catalyst systems including such catalyst articles. In particular, the catalyst composition includes a metal ion-exchanged molecular sieve ion-exchanged with at least one additional metal, which reduces the number of metal centers often present in metal promoted zeolite catalysts. Methods of making and using the catalyst composition are also provided, as well as emission treatment systems including a catalyst article coated with the catalyst composition. The catalyst article present in such emission treatment systems is useful to catalyze the reduction of nitrogen oxides in gas exhaust in the presence of a reductant while minimizing the amount of dinitrogen oxide emission.

Uses for a new crystalline molecular sieve designated SSZ-105 are disclosed. SSZ-105 is synthesized using N,N-dimethylpiperidinium cations as a structure directing agent. SSZ-105 is a disordered aluminosilicate molecular sieve comprising at least one intergrown phase of an ERI framework type molecular sieve and an LEV framework type molecular sieve.

Uses for a new crystalline molecular sieve designated SSZ-105 are disclosed. SSZ-105 is synthesized using N,N-dimethylpiperidinium cations as a structure directing agent. SSZ-105 is a disordered aluminosilicate molecular sieve comprising at least one intergrown phase of an ERI framework type molecular sieve and an LEV framework type molecular sieve.

A catalyst for oxidising ammonia comprises a selective catalytic reduction (SCR) catalyst and a composite heterogeneous extruded honeycomb having longitudinally extending parallel channels, which channels being defined in part by channel walls having a total longitudinal length, wherein the channel walls comprise a pore structure including a periodic arrangement of porous cells embedded in an inorganic matrix component, at least some of which porous cells are defined at least in part by an active interface layer of a catalytically active material comprising a precious metal supported on particles of a support material.

A catalyst for oxidising ammonia comprises a selective catalytic reduction (SCR) catalyst and a composite heterogeneous extruded honeycomb having longitudinally extending parallel channels, which channels being defined in part by channel walls having a total longitudinal length, wherein the channel walls comprise a pore structure including a periodic arrangement of porous cells embedded in an inorganic matrix component, at least some of which porous cells are defined at least in part by an active interface layer of a catalytically active material comprising a precious metal supported on particles of a support material.

Provided is a catalyst composition comprising a small pore molecular sieve, about 0.5-5 weight percent of a transition metal (T.sub.M) selected from copper and/or iron, based on the total weight of the zeolite, and about 0.5-5 weight percent nickel, based on the total weight of the molecular sieve, wherein the transition metal and nickel are present in a T.sub.M:Ni ratio of about 10:1 to about 1:2. Also provided is a synthesis method for preparing a small pore molecular sieve having both Cu and Ni incorporated in situ. Also provided is a method for using such a catalyst for selectively reducing NOx in an exhaust gas.

A filter for filtering particulate matter (PM) from exhaust gas emitted from a compression ignition engine, which filter comprising a porous substrate having inlet surfaces and outlet surfaces, wherein the inlet surfaces are separated from the outlet surfaces by a porous structure containing pores of a first mean pore size, wherein the porous substrate is coated with a wash coat comprising a plurality of solid particles comprising a molecular sieve promoted with at least one metal wherein the porous structure of the wash coated porous substrate contains pores of a second mean pore size, and wherein the second mean pore size is less than the first mean pore size.