Abstract:
Catalyst washcoats with improved porosity and methods for making the washcoats are provided. The process comprises incorporation of an oil-in-water macroemulsion into the catalyst slurry prior to washcoating the carrier substrate, and calcining the washcoated carrier substrate to remove the oil-in-water macroemulsion. Also provided are catalyst articles comprising the washcoat and methods for abatement of exhaust gas emissions.
Abstract:
Disclosed are catalysts comprised of platinum and gold. The catalysts are generally useful for the selective oxidation of compositions comprised of a primary alcohol group and at least one secondary alcohol group wherein at least the primary alcohol group is converted to a carboxyl group. More particularly, the catalysts are supported catalysts including particles comprising gold and particles comprising platinum, wherein the molar ratio of platinum to gold is in the range of about 100:1 to about 1:4, the platinum is essentially present as Pt(0) and the platinum-containing particles are of a size in the range of about 2 to about 50 nm. Also disclosed are methods for the oxidative chemocatalytic conversion of carbohydrates to carboxylic acids or derivatives thereof. Additionally, methods are disclosed for the selective oxidation of glucose to glucaric acid or derivatives thereof using catalysts comprising platinum and gold. Further, methods are disclosed for the production of such catalysts.
Abstract:
Niobia- and tantala-doped ceria catalysts, their use in selective catalytic reduction (SCR) processes, and a compact after-treatment system for exhaust gases are disclosed. In some aspects, the catalyst comprises at least 91 wt. % of ceria and 0.1 to 9 wt. % of niobia or tantala doped on the ceria. While conventional SCR catalysts can deactivate at higher temperatures, the doped cerias, particularly ones having as little as 1 or 2 wt. % of Nb2O5 or Ta2O5, are activated toward NOx conversion by calcination. The doped cerias are also valuable for SCRF® catalyzed filter applications, including an after-treatment system that comprises a diesel particulate filter having inlets and outlets, and a dual-function catalyst coated on the inlets, outlets, or both. Compared with conventional SCR catalysts, the niobia or tantala-doped cerias enable a higher level of NO2 to be present.
Abstract translation:公知了氧化铌和钽铝氧化物催化剂,它们在选择性催化还原(SCR)工艺中的应用,以及用于废气的紧凑的后处理系统。 在一些方面,催化剂包含至少91wt。 %的二氧化铈和0.1〜9wt。 在氧化铈上掺杂的氧化铌或钽的百分比。 虽然常规SCR催化剂可以在较高温度下失活,但是掺杂的二氧化铈,特别是具有少至1或2wt。 Nb 2 O 5或Ta 2 O 5的%通过煅烧而被NOx活化。 掺杂的二氧化铈对于SCRF®催化过滤器应用也是有价值的,其包括后处理系统,其包括具有入口和出口的柴油微粒过滤器,以及涂覆在入口或出口上的双功能催化剂。 与传统的SCR催化剂相比,氧化铌或氧化钽掺杂的铈氧化物可以提供更高水平的NO2。
Abstract:
The present disclosure provides an exhaust gas purification catalyst having improved performance for purifying an exhaust gas, in particular, an exhaust gas containing NOx. The exhaust gas purification catalyst of the present disclosure includes Rh-supporting composite oxide support particles containing Al, Zr, and Ti and Rh-supporting aluminum phosphate-based support particles. Furthermore, in the exhaust gas purification catalyst of the present disclosure, the ratio of the moles of metals constituting the aluminum phosphate-based support particles, relative to the total moles of metals constituting the composite oxide support particles and the aluminum phosphate-based support particles is 7.5% or more and 15.0% or less.
Abstract:
A catalyst for storing nitrogen oxides (NOx) in an exhaust gas from a lean burn engine comprising a NOx storage material and a substrate, wherein the NOx storage material comprises a NOx storage component and an NO oxidation promoter on a support material, wherein the NO oxidation promoter is manganese or an oxide, hydroxide or carbonate thereof.
Abstract:
The invention relates to a method for producing a catalytic composition, wherein the catalytic composition has a high activity and selectivity with regard to the oxidation of CO and a reduced activity with regard to the oxidation of NO. The invention also relates to the catalyst produced using the method according to the invention. Finally, the invention is directed towards an exhaust-gas cleaning system which comprises the catalyst according to the invention.
Abstract:
The present invention describes a double-layer three-way catalyst on an inert catalyst support comprising a first layer in direct contact with the inert catalyst support, comprising active alumina, a cerium/zirconium mixed oxide and palladium and a second layer applied to the first layer and in direct contact with the exhaust gas to be purified, comprising active alumina and rhodium, characterized in that the second layer is free of cerium and cerium containing materials, the use of such catalyst for cleaning the exhaust gases of a motor vehicle equipped with a gasoline engine and an exhaust gas treatment system comprising such catalyst up stream of a gasoline particulate filter (GPF).
Abstract:
An object of the present invention is to provide a catalyst for treating exhaust gas adapted not only to remove CO and VOCs based on unsaturated hydrocarbons such as C2H4 but also to accelerate a decomposition reaction of saturated hydrocarbons such as propane and to provide a method for producing such a catalyst for treating exhaust gas. The present invention provides a catalyst for treating an exhaust gas containing carbon monoxide and volatile organic compounds, the catalyst comprising a substrate containing a NOx removal catalyst component and a porous inorganic compound layer containing a noble metal, the layer being applied to the substrate.
Abstract translation:本发明的目的是提供一种用于处理废气的催化剂,其不仅适用于除去基于不饱和烃如C 2 H 4的CO和VOC,而且还用于加速饱和烃如丙烷的分解反应,并提供一种生产方法 这种用于处理废气的催化剂。 本发明提供一种用于处理含有一氧化碳和挥发性有机化合物的废气的催化剂,该催化剂包括含有除去NOx的催化剂组分的基质和含有贵金属的多孔无机化合物层,该层被施加到基材上。
Abstract:
A method of preparing a catalyst composition for producing a stable ratio of NO2 to NO in an exhaust system of a compression ignition engine is described. The method comprises: (i) preparing a first composition comprising a platinum (Pt) compound disposed or supported on a support material; (ii) preparing a second composition by reducing the platinum (Pt) compound to platinum (Pt) with a reducing agent; and (iii) heating the second composition to at least 650° C.
Abstract:
A device includes a first catalyst 41 including a Pd-containing catalyst layer and a Rh-containing catalyst layer and a second catalyst 42 containing Pt-loaded alumina and containing neither Rh nor Pd. The first catalyst or the second catalyst are disposed in one place in such a manner that one of the first catalyst 41 or the second catalyst 42 is located upstream of the other in a flow direction of an exhaust gas from an engine 1.