The present application is directed to a method for the conversion of nitrous acid to dinitrogen gas. In particular, the present application relates to a method for the conversion of nitrous acid to dinitrogen gas by contacting the nitrous acid with an amine-functionalized metal organic framework.

Disclosed is a process for the preparation of 1,3,3,3-tetrafluoropropene, comprising: (a) a compound having the formula CF.sub.3-xCl.sub.xCHClCHF.sub.2-yCl.sub.y and in the presence of a compound catalyst, undergoes, through n serially-connected reactors, gas-phase fluorination with hydrogen fluoride, producing 1,2,3-trichloro-1,1,3-trifluoropropane, and 1,2-dichloro-1,1,3,3-tetrafluoropropane; in said formula, x=1, 2 or 3; y=1 or 2, and 3≦x+y≦5; (b) 1,2,3-trichloro-1,1,3-trifluoropropane, and 1,2-dichloro-1,1,3,3-tetrafluoropropane undergo, in the presence of a dehalogenation catalyst, gas-phase dehalogenation with hydrogen, producing 3-chloro-1,3,3-trifluoropropene, and 1,1,3,3-tetrafluoropropene; (c) 3-chloro-1,3,3-trifluoropropene and 1,1,3,3-tetrafluoropropene undergo, in the presence of a fluorination catalyst, gas-phase fluorination with hydrogen fluoride, producing 1,3,3,3-tetrafluoropropene. The present invention is primarily used to produce 1,3,3,3-tetrafluoropropene.

A method of selectively catalysing the reduction of oxides of nitrogen (NO.sub.x) including nitrogen monoxide in an exhaust gas of a stationary source of NO.sub.x emissions also containing oxides of sulfur (SO.sub.x) comprising the steps of passively oxidising nitrogen monoxide to nitrogen dioxide (NO.sub.2) over an oxidation catalyst comprising a platinum group metal so that a NO.sub.2/NO.sub.x content is from 40-60%; introducing a nitrogenous reductant into the exhaust gas; and contacting exhaust gas having the 40-60% NO.sub.2/NO.sub.x content and containing the nitrogenous reductant with a selective catalytic reduction (SCR) catalyst comprising an aluminosilicate zeolite promoted with copper.

The present invention relates to a selective catalytic reduction catalyst for the treatment of an exhaust gas of a combustion engine, the catalyst comprising a substrate comprising an inlet end, an outlet end, a substrate axial length extending from the inlet end to the outlet end and a plurality of passages defined by internal walls of the substrate extending therethrough; a coating disposed on the substrate (i), the coating comprising a first non-zeolitic oxidic material comprising aluminum, an 8-membered ring pore zeolitic material comprising one or more of copper and iron, and a second non-zeolitic oxidic material comprising cerium and one or more of zirconium, aluminum, silicon, lanthanum, niobium, iron, manganese, titanium, tungsten, copper, molybdenum, neodymium, cobalt, chromium, tin and praseodymium; wherein at least 65 weight-% of the coating consist of the 8-membered ring pore zeolitic material comprising one or more of copper and iron.

One object is to provide an aldehyde decomposition catalyst, and an exhaust gas treatment apparatus and an exhaust gas treatment method using the aldehyde decomposition catalyst that achieve low cost and sufficient aldehyde decomposition performance with a small amount of the catalyst. An aldehyde decomposition catalyst of the present invention is made of a zeolite in a cation form NH.sub.4 having a structure selected from MFI and BEA and carrying at least one metal selected from the group consisting of Cu, Mn, Ce, Zn, Fe, and Zr.

The disclosure provides a system and a method for reducing hazardous gases, including PHGs, through one or more photocatalysts in a filter system. A microstructure of the photocatalytic filter can be formed using biological systems as a template for the photocatalysts to be deposited thereon. The biological system can be removed by heat, oxidation, or by chemical processes to leave the photocatalytic template as a filter for the gases. In various embodiments, multiple photocatalysts can be activated at different wavelengths to filter different gases, or multiple photocatalysts can be activated at the same wavelength to filter different gases, or a photocatalyst can be activated at different wavelengths to filter different gases, or some combination thereof. The activation can be sequential or concurrent. For multiple layers of photocatalysts, the sequence of the photocatalysts can be arranged to reduce damaging output from an upstream photocatalyst to one or more downstream photocatalysts.

The present disclosure provides a monolith substrate used for an exhaust gas purifying catalyst that improves purification performance, a method for producing such monolith substrate, and an exhaust gas purifying catalyst comprising such monolith substrate. The present disclosure relates to a monolith substrate comprising an alumina-ceria-zirconia composite oxide and alumina, a method for producing such monolith substrate, and an exhaust gas purifying catalyst comprising such monolith substrate.

Zero-Rare Earth Metal (ZREM) and Zero-platinum group metals (ZPGM) compositions of varied binary spinel oxides are disclosed as oxygen storage material (OSM) to be used within TWC systems. The ZREM-ZPGM OSM systems comprise binary non-Cu spinel oxides of Co—Fe, Fe—Mn, Co—Mn, or Mn—Fe. The oxygen storage capacity (OSC) property associated with the non-Cu ZREM-ZPGM OSM systems is determined employing isothermal OSC oscillating condition testing. Further, the OSC test results compare the OSC properties of a ZREM-ZPGM reference OSM system including a Cu—Mn binary spinel oxide and PGM reference catalysts including Ce-based OSMs. The non-Cu spinel oxides ZREM-ZPGM OSM systems exhibit significantly improved OSC properties, which are greater than the OSC property of the Ce-based OSM PGM reference systems.

A lean gasoline exhaust treatment catalyst article is provided, the article comprising a catalytic material applied on a substrate, wherein the catalytic material comprises a first composition and a second composition, wherein the first and second compositions are present in a layered or zoned configuration, the first composition comprising palladium impregnated onto a porous refractory metal oxide material and rhodium impregnated onto a porous refractory metal oxide material; and the second composition comprising platinum impregnated onto a porous refractory metal oxide material. Methods of making and using such catalyst articles and the associated compositions and systems employing such catalyst articles are also described.

Phosphorus tolerant or resistant three-way catalysts (TWC) are disclosed. The TWC may include a substrate defining a plurality of channels. It may include front and rear washcoat portions overlying the substrate and having respective first and second washcoat loadings, the first washcoat loading being at most 2.0 g/in.sup.3 and less than the second washcoat loading. The front washcoat portion may include a catalyst material supported on a support material comprising a cerium oxide, such as ceria or CZO, or a pre-phosphated material, such as AlPO.sub.4, or CePO.sub.4. In one embodiment, the support material may comprise at least 85 wt. % of a cerium oxide or at least 85 wt. % of a phosphate-containing material. The front portion and the underlying substrate may comprise from 3 to 25 vol. % of the three-way catalyst or the front portion may overly up to an initial 15% of an axial length of the substrate.