A vehicular exhaust filter (2) comprising a porous substrate having an inlet face and an outlet face with the porous substrate comprising inlet channels extending from the inlet face and outlet channels extending from the outlet face is disclosed. The inlet channels and the outlet channels are separated by a plurality of filter walls having a porous structure. The vehicular exhaust filter (2) is loaded with a refractory powder having a tapped density before loading of less than 0.10 g/cm.sup.3 and the vehicular exhaust filter has a mass loading of the refractory powder of less than 10 g/l.

Provided is a method for manufacturing a single-atom catalyst supported on a carbon support, including treating a mixture of a precursor of a carbon support and a precursor of a hetero element other than carbon through a dry vapor phase process, thereby supporting, on a carbon support, a single-atom catalyst containing a hetero element other than carbon.

Bimetallic three-way catalyst devices include a support body, one or more Rh bulk deposits disposed on the support body, and a plurality of Pt atomic clusters disposed on the surface of each of the Rh bulk deposits. Substantially no Pt is deposited on the support body. At least 85% by weight of the Pt atomic clusters comprise up to 10 atoms and the maximum Pt atomic cluster size is 200 Pt atoms. The combined loading of Rh and Pt can be less than 1.5% by weight relative to the weight of the support body. The molar ratio of Rh in a bulk Rh deposit to Pt disposed on the surface of that deposit is at least 5:1.

A catalytic wall-flow monolith filter having three-way catalytic activity for use in an emission treatment system of a positive ignition internal combustion engine comprising a porous filter substrate having a first face and a second face defining a longitudinal direction there between and first and second pluralities of channels extending in the longitudinal direction, wherein the first plurality of channels is open at the first face and closed at the second face and the channels of the first plurality of channels are defined in part by channel wall surfaces, wherein the second plurality of channels is open at the second face and closed at the first face and the channels of the second plurality of channels are defined in part by channel wall surfaces and wherein channel walls between the channel wall surfaces of the first plurality of channels and the channel wall surfaces of the second plurality of channels are porous, wherein a first on-wall coating comprising catalytic material having a layer thickness is present on at least the channel wall surfaces of the first plurality of channels, wherein the catalytic material on channel wall surfaces of the first plurality of channels comprises one or more platinum group metal selected from the group consisting of (i) rhodium (Rh) only; (ii) palladium (Pd) only; (iii) platinum (Pt) and rhodium (Rh); (iv) palladium (Pd) and rhodium (Rh); and (v) platinum (Pt), palladium (Pd) and rhodium (Rh) and a refractory metal oxide support, wherein: (i) an amount by weight of the one or more platinum group metal, per unit volume of the on-wall coating present on channel wall surfaces of the first plurality of channels varies continually along the longitudinal direction; and/or (ii) the layer thickness of the on-wall coating present on channel wall surfaces of the first plurality of channels varies continually along the longitudinal direction.

Subject of the invention is an exhaust gas purification system for a gasoline engine, comprising in consecutive order the following devices: a first three-way-catalyst (TWC1), a gasoline particulate filter (GPF) and a second three-way-catalyst (TWC2), wherein the wash coat load (WCL) of the TWC2 is greater than the WCL of the GPF, wherein the WCL is determined in g/l of the volume of the device,

The invention also relates to methods in which the system is used and uses of the system.

Methods are provided for emissions control of a vehicle. In one example, a catalyst may include a cerium-based support material and a transition metal catalyst loaded on the support material, the transition metal catalyst including nickel and copper, wherein nickel in the transition metal catalyst is included in a monatomic layer loaded on the support material. In some examples, limiting nickel to the monatomic layer may mitigate extensive transition metal catalyst degradation ascribed to sintering of thicker nickel washcoat layers. Further, by utilizing the cerium-based support material, side reactions involving nickel in the transition metal catalyst with other support materials may be prevented.

Alkyl-demethylation of C2+-hydrocarbyl substituted aromatic hydrocarbons can be utilized to treat one or more of a heavy naphtha reformate stream, a hydrotreated SCN stream, a C8 aromatic hydrocarbon isomerization feed stream, a C9+ aromatic hydrocarbon transalkylation feed stream, and similar hydrocarbon streams to produce additional quantity of xylene products.

The invention discloses a dinuclear rhodium complex-doped platinum/hollow mesoporous silica sphere composite material, and a preparation method and an application thereof. The preparation method comprises the following steps: preparing hollow mesoporous silica by a selective etching technology, uniformly distributed a precious metal platinum in the channels of the hollow mesoporous silica by using simple impregnation, and mixing the obtained catalyst with dinuclear rhodium complex adsorbed silica gel to obtain the composite material integrating a chromogenic probe with the catalyst. The preparation method is simple, and the chromogenic performance of the dinuclear rhodium complex material and catalysis performance of the catalyst can achieve simultaneous detection and catalyst of CO; and the dinuclear rhodium complex has obvious response to CO, and has chromogenic change in the presence of 50 ppm CO, and the product prepared through the preparation method has excellent CO detection and treatment properties, and highly facilitates industrial application.

Alkyl-demethylation of C2+-hydrocarbyl substituted aromatic hydrocarbons can be utilized to treat one or more of a heavy naphtha reformate stream, a hydrotreated SCN stream, a C8 aromatic hydrocarbon isomerization feed stream, a C9+ aromatic hydrocarbon transalkylation feed stream, and similar hydrocarbon streams to produce additional quantity of xylene products.

An exhaust gas purification system for a gasoline engine is described the system comprising in consecutive order the following devices: •a first three-way-catalyst (TWC1), a gasoline particulate filter (GPF) and a second three-way-catalyst (TWC2), •wherein the oxygen storage capacity (OSC) of the GPF is greater than the OSC of the TWC1, wherein the OSC is determined in mg/l of the volume of the device.