The oxide-containing particles (transition metal oxide-containing cerium dioxide particle) exert a catalyst performance, and include at least an iron oxide containing an iron component and a manganese oxide containing a manganese component on a surface of each of cerium dioxide particles, wherein the iron oxide and manganese oxide have smaller particle diameters than that of the cerium dioxide particles, and the content rate of the iron oxide and the manganese oxide is within the range of from 15.0% by mass to 35.0% by mass.

A process for producing a ceramic catalyst involves the steps of: a) providing functional particles having a catalytically inactive pore former as a support surrounded by a layer of a catalytically active material, b) processing the functional particles with inorganic particles to form a catalytic composition, c) treating the catalytic composition thermally to form a ceramic catalyst, wherein the ceramic catalyst comprises at least porous catalytically inactive cells which are formed by the pore formers in the functional particles, which are embedded in a matrix comprising the inorganic particles, which form a porous structure and which are at least partly surrounded by an active interface layer comprising the catalytically active material of the layer of the functional particles.

An SCR catalyst produced in by this method has an improved NO.sub.x conversion rate compared to a conventionally produced SCR catalyst.

The present invention pertains to a catalyst for use in the selective catalytic reduction (SCR) of nitrogen oxides comprising: • a monolithic substrate and • a coating A which comprises an oxidic metal carrier comprising an oxide of titanium and a catalytic metal oxide which comprises an oxide of vanadium wherein the mass ratio vanadium/titanium is 0.07 to 0.26.

Effect of the type of ZPGM material composition to improve thermal stability of ZPGM catalyst systems for TWC application is disclosed. ZPGM catalyst system samples are prepared and configured with washcoat on ceramic substrate, overcoat including doped Zirconia support oxide, and impregnation layer including either Cu.sub.1Mn.sub.2O.sub.4 spinel or Cu.sub.1Co.sub.1Mn.sub.1O.sub.4 spinel. Testing of ZPGM catalyst samples including variations of aging temperatures and different impregnation layer materials are developed under isothermal steady state sweep test condition for ZPGM catalyst systems to evaluate performance especially NO.sub.x conversions and level of thermal stability. As a result disclosed ZPGM catalyst systems with most suitable spinel that includes Cu.sub.1Co.sub.1Mn.sub.1O.sub.4 in impregnation layer exhibit high NOx conversion and significant improved thermal stability compare to Cu.sub.1Mn.sub.2O.sub.4 spinel, which is suitable for under floor and close coupled TWC application. The effect of adding Co to Cu—Mn spinel composition to improve thermal stability confirmed by TPR measurement.

An ammonia slip catalyst having an SCR catalyst and an oxidation catalyst comprising at least two metals, each of which is selected from a specific group, and a substrate upon which at least oxidation catalyst is located is described. The ammonia slip catalyst can have dual layers, with one of the layers containing an SCR catalyst, a second layer containing the oxidation catalyst with comprises at least two metals, each of which is selected from a specific group, and the ammonia slip catalyst does not contain a platinum group metal. Methods of making and using the ammonia slip catalyst to reduce ammonia slip are described.

A particulate filter includes a base material having a wall-flow structure including porous partition walls partitioning inlet and outlet cells, and wash-coating layers held inside partition walls. The wash-coating layers include inlet layers each formed from vicinity of an end portion at exhaust gas inflow side to have predetermined length and thickness and outlet layers each formed from vicinity of end portion at exhaust gas outflow side to have a predetermined length and thickness. The inlet and the outlet layers partially overlap with each other. Inlet layers of particulate filter contain substantially no noble metal catalyst, and outlet layers contain noble metal catalyst. Accordingly, PM collection performance can be easily enhanced in inlet region, and high gas distributability (pressure loss suppression performance) can be maintained in outlet region. Accordingly, it is possible to provide particulate filter capable of achieving high levels of PM collection performance and pressure loss suppression performance.

JMZ-1, a zeolite having a CHA structure and containing trimethyl(cyclohexylmethyl)ammonium cations as a structure directing agent is described. A calcined zeolite, JMZ-1C, that does not contain a structure directing agent, is also described. Metal containing JMZ-1C has improved SCR activity compared to CHA-containing zeolites having the same metal loading and comparable silica:alumina ratios (SAR). Methods of preparing JMZ-1, JMZ-1C and metal containing calcined counterparts of JMZ-1C are described along with methods of using JMZ-1C and metal containing calcined counterparts of JMZ-1C in treating exhaust gases.

The present disclosure provides SCR catalyst compositions, catalyst articles, and catalyst systems, as well as methods of reducing the amount of NOx present in an engine exhaust gas, particularly exhaust from a gasoline engine. The catalyst compositions particularly can comprise a doped ceria substrate, particularly a ceria support doped with at least a niobia component, and optionally further doped with a further material, particularly a base metal oxide (BMO).

The present invention pertains to a catalyst for use in the selective catalytic reduction (SCR) of nitrogen oxides comprising a monolithic substrate and a coating A, which comprises an oxidic metal carrier comprising an oxide of titanium and a catalytic metal oxide which comprises an oxide of vanadium wherein the mass ratio vanadium/titanium is 0.07 to 0.26.

The exhaust gas cleaning catalyst according is provided with a substrate and a catalyst coat layer formed on a surface of the substrate. The catalyst coat layer is formed as a laminate structure having an upper layer and a lower layer. The upper layer is a Pd-free layer that does not contain Pd, and the lower layer is a Pd-containing layer. In addition, when a region of the lower layer that corresponds to 20% of the length of the exhaust gas cleaning catalyst from the exhaust gas inlet side end towards the exhaust gas outlet side of the exhaust gas cleaning catalyst is divided into four equal regions to be each 5% of the length, the relationship A>B>C is satisfied, where A, B, and C represents the Pd content in the first, second, and third region respectively.