The present disclosure relates to a substrate containing passive NO.sub.x adsorption (PNA) materials for treatment of gases, and washcoats for use in preparing such a substrate. Also provided are methods of preparation of the PNA materials, as well as methods of preparation of the substrate containing the PNA materials. More specifically, the present disclosure relates to a coated substrate containing PNA materials for PNA systems, useful in the treatment of exhaust gases. Also disclosed are exhaust treatment systems, and vehicles, such as diesel or gasoline vehicles, particularly light-duty diesel or gasoline vehicles, using catalytic converters and exhaust treatment systems using the coated substrates.

The present disclosure features a method of making an engine aftertreatment catalyst, where the engine aftertreatment catalyst includes a metal oxide, a metal zeolite, and/or vanadium oxide when the metal oxide is different from vanadium oxide, each of which can be independently surface-modified with a surface modifier. The method includes providing a solution including an organic solvent and an organometallic compound; mixing the solution with a metal oxide, a metal zeolite, and/or a vanadium oxide to provide a mixture; drying the mixture; and calcining the mixture to provide a surface-modified metal oxide catalyst, a surface-modified metal zeolite catalyst, and/or a surface-modified vanadium oxide catalyst. The organometallic compound can be, for example, a metal alkoxide, a metal carboxylate, a metal acetylacetonate, and/or a metal organic acid ester.

The present disclosure is directed at a ruthenium based catalyst for NOx reduction. More specifically, ruthenium based catalysts are used for NOx reduction in an internal combustion engine to reduce NO.sub.x to nitrogen, at relatively high conversion and selectivity, using carbon monoxide and hydrogen as reductants. The ruthenium based catalyst has particular utility in exhaust gas recirculation such as in dedicated exhaust gas recirculation (D-EGR) systems.

An exhaust gas-purifying catalyst includes a support and a catalytic metal supported thereby. The support includes a composite oxide represented by AO.xB.sub.2-C.sub.O.sub.3, wherein A represents at least one of an element having a valence of 1 and an element having a valence of 2, B represents an element having a valence of 3, C represents one or more elements selected from iridium, ruthenium, tantalum, niobium, molybdenum, and tungsten, x represents a numerical value of 1 to 6, and a represents a numerical value greater than 0 and less than 2. The catalytic metal includes one or more precious metals selected from rhodium, palladium, and platinum.

A diesel engine exhaust gas treatment system with enhanced nitrogen oxide purification performance includes a nitrogen oxide adsorption part nitrogen adsorbing oxide (NO.sub.x) at a temperature of less than 200 C. and desorbing the nitrogen dioxide (NO.sub.2) at a temperature of 200 C. or more; and a nitrogen oxide purification part disposed at a lower side of the nitrogen oxide adsorption part and purifying the nitrogen oxide (NO.sub.x).

A material is described of formula Na.sub.xM.sub.yAl.sub.aSi.sub.bO.sub. with Face Centered Cubic (fcc) lattices forming F-4 3 m cubic structure, wherein M is at least one of lithium, potassium, rubidium, caesium, vanadium, chromium, iron, cobalt, nickel, ruthenium, rhodium, palladium, silver, osmium, iridium, platinum, gold, and cerium; 0<x+y22/3; wherein when y=0, 4<x/3, when 0<y/3, 0x<22/3, and when M is potassium, x>0; 1a3; 1b3; and 0<32/3. An exhaust gas system comprising the material and a method are also described herein.

Provided are a nitrous oxide decomposition method and a decomposition apparatus capable of efficiently decomposing nitrous oxide in a nitrous oxide-containing gas. Disclosed are: a method of decomposing nitrous oxide, which includes the step of bringing a catalyst including a titanium oxide-containing carrier carrying a component containing at least one kind selected from the group consisting of ruthenium and ruthenium compounds into contact with a nitrous oxide-containing gas containing nitrous oxide, water vapor and ammonia; and a nitrous oxide decomposition apparatus including a reactor filled with the above catalyst and a line that is connected to the reactor and supplies the nitrous oxide-containing gas to the reactor.

The present invention is concerned with oxygen storage materials. In particular an oxygen storage material (OSM) is proposed which comprises a certain mixed oxide as the oxygen storage component. The oxygen storage material can be used in conventional manner in three-way catalysts or NOx-storage catalysts for example.

The present invention relates to a bimetallic catalyst for ammonia oxidation, a method for producing a bimetallic catalyst for ammonia oxidation and a method for tuning the catalytic activity of a transition metal. By depositing an overlayer of less catalytic active metal onto a more catalytic active metal, the total catalytic activity is enhanced.

A passive NO.sub.x adsorber is disclosed. The passive NO.sub.x adsorber is effective to adsorb NO.sub.x at or below a low temperature and release the adsorbed NO.sub.x at temperatures above the low temperature. The passive NO.sub.x adsorber comprises a noble metal and a molecular sieve having an LTL Framework Type. The invention also includes an exhaust system comprising the passive NO.sub.x adsorber, and a method for treating exhaust gas from an internal combustion engine utilizing the passive NO.sub.x adsorber.