Provided are catalyst articles, methods of manufacturing catalyst articles, and methods for controlling emissions in diesel engine exhaust streams with catalyst articles, where the emission treatment system of various embodiments effectively treats diesel engine exhaust with a catalyst article. In one or more embodiments, the catalyst articles have a platinum group metal end coating covering an outlet end surface of the catalytic article. In one or more embodiments, a method is provided where an applicator transfers a platinum group metal coating to an outlet end face of a catalytic article.

In some embodiments, the present disclosure pertains to methods of removing heteroatoms from a fluid by associating the fluid with one or more adsorbents, where the association results in the removal of the heteroatoms from the fluid. The association may occur by associating the fluid with a single adsorbent or a plurality of adsorbents in a sequential manner that maximizes heteroatom removal efficacy. The methods may be utilized to remove heteroatom-containing compounds from various fluids, such as fuels, hydrocarbons, alcohols, water, organic solvents, and combinations thereof. The one or more adsorbents may include, without limitation, activated carbon, zeolites, ion exchanged zeolites, ion impregnated zeolites, alumina, alumina nanowires, carbon-based supports, and combinations thereof. The methods of the present disclosure can be utilized to reduce heteroatoms in the fluid by more than about 50%, by more than about 80%, or by more than about 99%.

Method for the preparation of a honeycomb catalyst including the steps of pre-coating a non-woven fibrous sheet, corrugating the fibrous sheet and rolling-up or stacking-up the corrugated sheet to form a honeycomb body. The honeycomb body is subsequently washcoated, including the addition of at least one catalytically active compound.

An apparatus and a process for reducing the concentration of NOx nitrogen oxides in residual gas may be employed during shutdown and/or startup of apparatuses for preparing nitric acid. An example apparatus for reducing NOx nitrogen oxides may include a reactor that produces NOx nitrogen oxides, an absorption apparatus that absorbs at least part of the NOx nitrogen oxides produced in an aqueous composition, a residual gas purification plant that decomposes and/or reduces unabsorbed NOx nitrogen oxides, feed means for feeding the NOx nitrogen oxides to the absorption apparatus, discharge means for discharging the unabsorbed NOx nitrogen oxides from the absorption apparatus to the residual gas purification plant, and a bypass that transfers a gas mixture from the reactor to the residual gas purification plant while bypassing the absorption apparatus during startup and/or shutdown of the apparatus for preparing nitric acid.

Method for preparing a catalytic fabric filter comprising the steps of a) providing a fabric filter substrate, preferably consisting of glass fibers, having a gas inlet surface and a gas outlet surface, the gas inlet surface is coated with a polymeric membrane, preferably consisting of polytetrafluoroethylene; b) providing an aqueous impregnation liquid comprising one or more catalyst metal precursor compounds; c) impregnating the fabric filter substrate with the impregnation liquid; and d) drying and thermally activating the impregnated fabric filter substrate at a temperature below 300 C. to convert the one or more metal compounds of the catalyst precursor to their catalytically active form, wherein the drying of the impregnated fabric filter substrate in step d) is performed from the gas outlet surface.

An improved catalytic filter material for use in removing target species found in a fluid stream is provided. The filter material includes water wettable, high temperature staple fibers in the form of porous substrates that are attached to a high temperature fluoropolymer woven scrim. The porous substrates have catalyst particles adhered (e.g., tethered) to the surfaces thereof by a polymer adhesive. Optionally, at least one microporous layer is positioned adjacent to or within the filter material.

The present disclosure describes hybrid binary catalysts (HBCs) that can be used as engine aftertreatment catalyst compositions, specifically 4-way catalyst compositions. The HBCs provide solutions to the challenges facing emissions control. In general, the HBCs include a porous primary catalyst and a secondary catalyst. The secondary catalyst partial coats the surfaces (e.g., the internal porous surface and/or the external surface) of the primary catalyst resulting in a hybridized composition. The synthesis of the HBCs can provide a primary catalyst whose entire surface, or portions thereof, can be coated with the secondary catalyst.

The present disclosure describes hybrid binary catalysts (HBCs) that can be used as engine aftertreatment catalyst compositions. The HBCs provide solutions to the challenges facing emissions control. In general, the HBCs include a porous primary catalyst and a secondary catalyst. The secondary catalyst partial coats the surfaces (e.g., the internal porous surface and/or the external surface) of the primary catalyst resulting in a hybridized composition. The synthesis of the HBCs can provide a primary catalyst whose entire surface, or portions thereof, can be coated with the secondary catalyst.

An exhaust gas after-treatment unit for an internal combustion engine, particularly for a motor vehicle, includes a first selective catalytic reduction (SCR) catalytic converter through which the exhaust gas from the internal combustion engine can flow and at least one particle filter for retaining the soot particles from the exhaust gas, The particle filter, which is located downstream from the first SCR catalytic converter, is equipped with a heavy metal and precious metal free catalyzing coating which oxidizes the soot particles retained by the particle filter, where downstream from the particle filter there is a second SCR catalytic converter through which the exhaust gas can flow.

A catalyst arrangement for use with a selective catalytic reduction system includes a frame and a plurality of catalyst elements coupled to the frame. The plurality of catalyst elements is arranged vertically among a plurality of vertical stations. The plurality of vertical stations is successively defined along a height of the catalyst arrangement. The catalyst elements of at least one of the vertical stations are arranged at a plurality of axial positions with respect to an axial direction of a flow of exhaust gases through the selective catalytic reduction system.