The present invention describes the process of preparing ceramic materials for absorption of acidic gases, mainly carbon dioxide, in exhaust systems and/or present indoors. Ceramic materials are formed by a mixture of alkali carbonate with alkaline earth metal oxide/hydroxide associated with a binding component, but non-limiting. The alkali carbonate comprises sodium, potassium carbonate, or a mixture of both. The alkaline earth metal oxide/hydroxide may be formed from magnesium oxide or magnesium hydroxide as well as calcium oxide and/or calcium hydroxide.

The present teachings are directed to inorganic oxide materials that include Al.sub.2O.sub.3, CeO.sub.2, and at least one of MgO and Pr.sub.6O.sub.11. The present teachings are also directed to catalysts having at least one noble metal supported on these inorganic oxide materials, as well as methods for treating exhaust gases from internal combustion engines using such catalysts.

A sorbent composition that is useful for injection into a flue gas stream of a coal burning furnace to efficiently remove mercury from the flue gas stream. The sorbent composition may include a sorbent with an associated ancillary catalyst component that is a catalytic metal, a precursor to a catalytic metal, a catalytic metal compound or a precursor to a catalytic metal compound. Alternatively, a catalytic metal or metal compound, or their precursors, may be admixed with the coal feedstock prior to or during combustion in the furnace, or may be independently injected into a flue gas stream. A catalytic promoter may also be used to enhance the performance of the catalytic metal or metal compound.

This disclosure is directed to catalyst compositions, catalytic articles for purifying exhaust gas emissions and methods of making and using the same. In particular, the disclosure relates to a catalytic article including a catalytic material on a substrate, wherein the catalytic material has a first layer and a second layer. The first layer provides effective lean NO.sub.x trap functionality and the second layer provides effective three-way conversion of carbon monoxide, hydrocarbons, and nitrogen oxides (NO.sub.x).

A sorbent composition that is useful for injection into a flue gas stream of a coal burning furnace to efficiently remove mercury from the flue gas stream. The sorbent composition may include a sorbent with an associated ancillary catalyst component that is a catalytic metal, a precursor to a catalytic metal, a catalytic metal compound or a precursor to a catalytic metal compound. Alternatively, a catalytic metal or metal compound, or their precursors, may be admixed with the coal feedstock prior to or during combustion in the furnace, or may be independently injected into a flue gas stream. A catalytic promoter may also be used to enhance the performance of the catalytic metal or metal compound.

The present invention relates to a catalyst which comprises a carrier substrate of length L, which extends between a first end face a and a second end face b, and catalytically active material zones A, B and C of different composition, wherein—material zone A comprises palladium or palladium and platinum with a weight ratio of Pd:Pt>1, and cerium oxide, —material zone B comprises platinum or platinum and palladium with a weight ratio of Pt:Pd>1, and cerium oxide and/or cerium/zirconium mixed oxide, and—material zone C comprises platinum or platinum and palladium with a weight ratio of Pt:Pd>1, and a carrier oxide, and wherein—material zone B is arranged above material zone A, and—material zone C is arranged above material zone B, and, starting from the second end face b of the carrier substrate, extends over a length of up to 60% of the length L. The invention also relates to a catalyst arrangement containing said catalyst.

An after treatment system is disclosed. The after treatment system may include a three-way catalyst (TWC), a selective catalytic reduction (SCR) catalyst, and a CO clean-up catalyst (CUC) on an exhaust pipe through which an exhaust gas flows. The CUC may include a zeolite in which Cu and Fe are ion-exchanged and CeO.sub.2 in which Pt is supported, wherein a weight ratio of the CeO.sub.2 to a total weight of the CUC is 30-70 wt % such that the CUC purifies NH.sub.3 at a lean air/fuel ratio and purifies NH.sub.3 during a delay time at a rich air/fuel ratio.

A sorbent composition that is useful for injection into a flue gas stream of a coal burning furnace to efficiently remove mercury from the flue gas stream. The sorbent composition may include a sorbent with an associated ancillary catalyst component that is a catalytic metal, a precursor to a catalytic metal, a catalytic metal compound or a precursor to a catalytic metal compound. Alternatively, a catalytic metal or metal compound, or their precursors, may be admixed with the coal feedstock prior to or during combustion in the furnace, or may be independently injected into a flue gas stream. A catalytic promoter may also be used to enhance the performance of the catalytic metal or metal compound.

A method and apparatus (1) for treating a filter (2) for filtering particulate matter from exhaust gas and a treated filter (2) are described. A reservoir (3) containing a dry powder (4) is provided. A vacuum generator (6) establishes a primary gas flow through a porous structure of the filter (2) by applying a pressure reduction to an outlet face of the filter (2). A spray device (7) receives the dry powder (4) from a transport device (8) and sprays the dry powder (4) towards the inlet face of the filter (2). A controller (9) is configured to control operation of at least the vacuum generator (6) and the spray device (7). The dry powder (4) comprises or consists of a metal compound for forming by thermal decomposition a metal oxide.

A portable or handhold air cleaning system, whose air flow pipeline made of highly reflective and low absorptive material for UVC or UVB light acts also as a UV light waveguide, is invented. The system features a TEC cooled LED light source; air flow warm up mechanism; and UV light absorption/air cleaning enhancement device. The system is useful for travellers and office workers during flu and hay-fever seasons.