An object of the present invention is to provide an exhaust gas purification catalyst with improved exhaust gas purification performance, and in order to achieve such an object, the present invention provides an exhaust gas purification catalyst (1A) including a substrate (10) and a catalyst layer (20) provided on the substrate (10), wherein the catalyst layer (20) includes a first layer (21) containing Rh, and Pd and/or Pt, and a second layer (22) containing Rh, and Pd and/or Pt, wherein a total content of Zr and Ce in terms of oxide and a content of aluminum element in terms of oxide in the first layer (21) are 70% by mass or more and 15% by mass or less, respectively, based on a mass of the first layer (21), and wherein a content of aluminum element in terms of oxide and a total content of Zr and Ce in terms of oxide in the second layer (22) are 75% by mass or more and 15% by mass or less, respectively, based on a mass of the second layer (22).

An object of the present invention is to provide an exhaust gas purification catalyst with improved exhaust gas purification performance, and in order to achieve such an object, the present invention provides an exhaust gas purification catalyst (1A) including a substrate (10) and a catalyst layer (20A) provided on the substrate (10), wherein a content of aluminum element in terms of oxide and a content of barium element in a first layer (21) of the catalyst layer (20A) are 15% by mass or more and 3% by mass or more, respectively, based on a mass of the first layer (21), and wherein a total of a content of zirconium element in terms of oxide and a content of a rare earth element in terms of oxide, a content of aluminum element in terms of oxide, and a content of barium element in a second layer (22) of the catalyst layer (20A) are 80% by mass or more, less than 15% by mass, and less than 3% by mass, respectively, based on a mass of the second layer (22).

This invention relates to an aqueous dispersion of particles, the dispersion having a particle content of 10-70 wt %, and the particles comprising, on an oxide basis: (a) 10-98 wt % in total of ZrO.sub.2+HfO.sub.2, and (b) 2-90 wt % in total of Al.sub.2O.sub.3, CeO.sub.2, La.sub.2O.sub.3, Nd.sub.2O.sub.3, Pr.sub.6O.sub.11, Y.sub.2O.sub.3, or a transition metal oxide, wherein the dispersion has a Z-average particle size of 100-350 nm and the particles have a crystallite size of 1-9 nm. The invention also relates to a substrate coated with the aqueous dispersion of particles.

The exhaust gas purification device includes a substrate, a first catalyst layer, and a second catalyst layer. The substrate includes an upstream end and a downstream end. The first catalyst layer contains first catalyst particles and lies on the substrate across a first region extending between the upstream end and a first position. The first position is at a first distance from the upstream end toward the downstream end. The second catalyst layer contains second catalyst particles and lies on the first catalyst layer across the first region. The second catalyst layer is provided with pores. Pore connectivity of the second catalyst layer is 5% to 35%. A mean value of areas of the pores of the second catalyst layer in a cross-sectional backscattered electron image of the second catalyst layer may be 0.7 ?m.sup.2 to 9.0 ?m.sup.2.

The invention relates to a process for recovering hydrogen (b) from crude gas (a) from a coke oven (110) in which the crude gas (a) produced in the coke oven (110) is initially compressed and in which impurities are subsequently removed from the crude gas (a) by pressure swing adsorption, wherein oxygen is depleted from the crude gas (a) using nonthermal plasma prior to the pressure swing adsorption, and to a plant for recovering hydrogen from crude gas.

An oxidation catalyst is described for treating hydrocarbons in an exhaust gas produced by an internal combustion engine, wherein the oxidation catalyst comprises a region disposed on a substrate, wherein the region comprises ruthenium (Ru) supported on a support material comprising a refractory oxide.

The present disclosure is directed at a dosing method and apparatus for treatment of reductant urea solutions with water soluble organometallic catalyst precursors which convert to active catalyst compounds in diesel exhaust gas systems. The active catalysts then promote hydrolysis of isocyanic acid into ammonia and/or decomposition of relatively high molecular weight deposits which deposits may otherwise reduce selective catalytic reduction efficiency.

The present disclosure provides a three-way conversion (TWC) catalyst composition, and a catalyst article comprising such a catalyst composition suitable for at least partial conversion of gaseous hydrocarbons (HCs), carbon monoxide (CO), and nitrogen oxides (NO.sub.x). Generally, the catalyst article includes a catalyst substrate having a plurality of channels adapted for gas flow, each channel having a wall surface and a catalytic coating on the surfaces or inside the pores of the wall. The catalytic coating generally includes a first washcoat with a platinum group metal (PGM) component and a first refractory metal oxide support and a second washcoat having a plurality of palladium-rhodium nanoparticles and a second refractory metal oxide support.

The composition of the invention is based on oxides of cerium, of zirconium and of at least one rare earth metal other than cerium, with a cerium oxide content of greater than 50% by weight and it has, after calcination at 1000? C. for 4 hours, a specific surface area of at least 20 m.sup.2/g and an amount of mobile oxygen between 200? C. and 400? C. of at least 0.8 ml O.sub.2/g. It is prepared by a process in which, in a reactor, a mixture of compounds of cerium, of zirconium and of the other rare earth metal is reacted continuously with a basic compound with a residence time of the reaction medium in the mixing zone of the reactor of at most 100 milliseconds; the precipitate is heated then brought into contact with a surfactant before being calcined.

Provided is a catalyst article for simultaneously remediating the nitrogen oxides (NOx), particulate matter, and gaseous hydrocarbons present in diesel engine exhaust streams. The catalyst article has a soot filter coated with a material effective in the Selective Catalytic Reduction (SCR) of NOx by a reductant, e.g., ammonia.