Zeolite catalysts and systems and methods for preparing and using zeolite catalysts having the CHA crystal structure are disclosed. The catalysts can be used to remove nitrogen oxides from a gaseous medium across a broad temperature range and exhibit hydrothermal stable at high reaction temperatures. The zeolite catalysts include a zeolite carrier having a silica to alumina ratio from about 15:1 to about 256:1 and a copper to alumina ratio from about 0.25:1 to about 1:1.

A honeycomb structure includes a pillar-shaped honeycomb structure body which has porous partition walls disposed to surround a plurality of cells Among the partition walls surrounding one of the cells, each of the partition walls constituting two opposite sides of the cell sandwiched therebetween is provided with a projection which project to extend into the cell and which is continuously provided in a direction in which the cell extends, and the area S1 of one region of the cell divided by a virtual line that virtually connects distal ends of the two projections in a section of the honeycomb structure body, and the area S2 of the other region (S1≤S2) of the cell satisfy 70%≤S1/S2×100%.

The system includes a robot multi-jet system having a spray section, a drier section, and a catalyst section. The drier section includes a warm air blower, the catalyst section includes a photocatalyst tank, and the spray section includes a plurality of jet extensions. A first jet extension connected to the photocatalyst tank sprays a uniform layer of a photocatalyst through a first set of jets, and a second jet extension that is mechanically connected to the drier section and in fluid communication with the warm air blower is configured to spray a gas onto an inner surface of the glass tube with a second set of jets. Both the drier section and the catalyst section are mounted on wheels to move the system on the inner surface of the glass tube. A motor is electrically connected to a battery mounted within the robot and mounted to the wheels.

The present invention relates to a particulate filter, in particular a particulate filter for use in an emission treatment system of an internal combustion engine. The particulate filter provides an advantageous combination of low back pressure and high fresh filtration efficiency.

A catalyst composition for selective catalytic reduction of NO.sub.x by ammonia or compounds, such as urea, generating ammonia under exhaust gas conditions. The composition includes a) a copper ion exchanged zeolite particles having a Si/Al.sub.2 molar ratio (SAR) of 15 or less and a copper content sufficiently high to perform the catalytic reduction, b) a nanocrystalline aluminium compound in an amount sufficient for stabilizing the zeolite, and c) a zirconium compound in an amount sufficient to improve hydrothermal durability of the catalyst composition.

There is provided an exhaust gas purification device that shows a high HC removal performance under a condition in which a rich air-fuel mixture is introduced. 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 is disposed on a surface of the partition wall in an upstream region including the upstream end of the substrate. The second catalyst layer is disposed inside the partition wall in a downstream region including the downstream end of the substrate. The first catalyst layer contains a first metal catalyst and alumina-zirconia composite oxide. The second catalyst layer contains a second metal catalyst.

A process for preparing an aromatic isocyanate by direct carbonylation of a nitro aromatic compound by reacting the nitro aromatic compound with carbon monoxide in the presence of a catalyst, characterized in that the catalyst contains a multi metallic material comprising one or more binary intermetallic phases of the general formula A.sub.xB.sub.y wherein: A is one or more element selected from Ni, Ru, Rh, Pd, Ir, Pt and Ag, B is one or more element selected from Sn, Sb, Pb, Zn, Ga, In, Ge and As, x is in the range 0.1-10, y in is in the range 0.1-10.

A process for coating substrates of motor vehicle exhaust gas catalysts is described, and includes steps of applying a suspension (e.g., washcoat) to a substrate, allowing a shear force to act on the applied washcoat, as in pressure transmitted by gas (e.g., air), and then sucking and/or pressing the washcoat into the substrate. The process in inclusive of providing the suspension (washcoat) containing the catalytic material from above in a metered charge process. An apparatus for carrying out the noted process steps is also featured.

A porous carbon material, wherein a half width (2θ) of a diffraction peak (10×) (38° to 49°) by X-ray diffraction is 4.2° or less, and wherein a ratio (mesopore volume/micropore volume) of a mesopore volume (cm.sup.3/g) measured by a BJH method to a micropore volume (cm.sup.3/g) measured by a HK method is 1.20 or more.

A cerium-zirconium-aluminum-based composite material, a cGPF catalyst and a preparation method thereof are provided. The cerium-zirconium-aluminum-based composite material adopts a stepwise precipitation method, firstly preparing an aluminum-based pre-treated material, then coprecipitating the aluminum-based pre-treated material with zirconium and cerium sol, and finally roasting at high temperature to obtain the cerium-zirconium-aluminum-based composite material. The cerium-zirconium-aluminum-based composite material has better compactness and higher density, and when it is used in cGPF catalyst, it occupies a smaller volume of pores on the catalyst carrier, such that cGPF catalyst has lower back pressure and better ash accumulation resistance, which is beneficial to large-scale application of cGPF catalyst.