A layered diesel oxidation catalyst for treatment of exhaust gas emissions from a diesel engine comprising: a flow-through monolith substrate having a honeycomb structure and comprising a front zone and a rear zone, wherein the front zone of the substrate comprises a combination of layers, one on top of another and comprising two or more of layers A, B and C; and the rear zone comprises Layer D, wherein: Layer A comprises platinum, palladium, or combinations thereof on a molecular sieve; Layer B comprises 1) platinum, palladium, or combinations thereof on a refractory metal oxide support; and 2) an alkaline earth metal, preferably barium, strontium or combinations thereof; Layer C comprises 1) a platinum group metal, which is platinum or a combination of both platinum and palladium on a refractory metal oxide support; and 2) a promoter metal, which is manganese and/or bismuth; and layer D comprises 1) platinum or a combination of both platinum and palladium on a refractory metal oxide support; and 2) manganese (Mn).

The present invention belongs to the technical field of functional organic macromolecule composite catalysts and involves the preparation of a nitrogen-doped lattice macromolecule composite loaded with an efficient denitrification and sulfur resistance catalyst, firstly using the method of adding metal salts to make a large amount of Ce.sup.3+, Ce.sup.4+, Sn.sup.3+ and Sn.sup.4+ ions accumulate around the cyanuric acid molecule. Afterwards, 2,4,6-triaminopyrimidine and cytosine were added to graft with the cyanuric acid to produce the N-doped macromolecule in the first stage. After that, potassium permanganate was used as the oxidizing agent, and redox reaction occurred on the surface of N-doped macromolecules, so that the manganese cerium tin catalyst was grown in situ on the surface of N-doped macromolecules, and finally calcined at once to cross-link the N-doped macromolecules to generate catalyst composites. The catalysts described in this invention have higher efficient NOx reduction and sulfur resistance performance.

An oven includes a cooking compartment for preparing food, a vapor extraction apparatus designed to extract vapors from the cooking compartment, and a catalyst fluidically coupled to the vapor extraction apparatus and designed to convert catalytically the vapors extracted in the vapor extraction apparatus. The catalyst includes a carrier and a layer of catalyst material applied on the carrier. In a normal mode of the oven for preparing food to be cooked, the catalyst has a concentration of acetic acid in the converted vapors which concentration of acetic acid amounts to less than or equal to 5 ppm. The oven is also able to operate in a pyrolysis mode which differs from the normal mode.

In certain exemplary embodiments, an air purifier comprises a housing defining an enclosure and having an air entrance and an air exit; a particulate filter; a NCCO filter material configured to adsorb and decompose at least one gaseous pollutant; an AOG configured to generate at least one oxidant; an oxidant remover configured to remove at least one oxidant; a fan unit configured to generate airflow from the air entrance to the air exit; wherein the particulate filter, the NCCO filter material, the AOG, the oxidant remover and the fan unit are positioned within the enclosure such that during operation, a flow of air passes from the air entrance to the air exit through the particulate filter and the NCCO filter material along a direction of the flow of air. In certain embodiments, the air purifier may ensure safety to users while efficiency in removing contaminants can be greatly improved.

Provide is a functional structural body that can suppress aggregation of metal oxide nanoparticles and prevent functional loss of metal oxide nanoparticles, and thus exhibit a stable function over a long period of time. A functional structural body (1) includes: a skeletal body (10) of a porous structure composed of a zeolite-type compound; and at least one type of metal oxide nanoparticles (20) containing a perovskite-type oxide present in the skeletal body (10), the skeletal body (10) having channels (11) that connect with each other, and the metal oxide nanoparticles (20) being present at least in the channels (11) of the skeletal body (10).

A functional structural body includes a skeletal body of a porous structure composed of a zeolite-type compound, and at least one type of metallic nanoparticles present in the skeletal body, the skeletal body having channels connecting with each other, the metallic nanoparticles being present at least in the channels of the skeletal body.

A system and method of regenerating a pre-purification vessel is provided that is particularly suitable for pre-purification of a feed air stream in cryogenic air separation unit that uses an oxygen-enriched purge gas stream for regeneration of the pre-purification unit. The disclosed pre-purification systems and methods are configured to remove substantially all of the water, carbon dioxide and other impurities from a feed air stream, optionally including hydrogen and carbon monoxide impurities. The method of regenerating a pre-purification vessel preferably involves regenerating the pre-purification vessel with an oxygen-enriched purge gas after depressurization of the vessel and thereafter partially repressurizing the pre-purification vessel with an auxiliary purge gas thereby diluting the oxygen concentration of the gases contained in the pre-purification vessel and optionally depressurizing the partially repressurized vessel.

A method for purifying a gas inside a polymer film production furnace with the use of the purification catalyst is provided. A purification catalyst for a gas inside a polymer film production furnace, contains a mixed oxide composed of a manganese-based oxide containing manganese and potassium and having a cryptomelane structure, and copper oxide. A method for purifying a gas inside a polymer film production furnace, includes a step 1 of bringing hot air containing volatile and/or sublimable organic substances, generated during production of a polymer film by the polymer film production furnace, into contact with the catalyst provided inside or outside the furnace, at a temperature in the range of 200 to 350° C. to decompose the organic substances oxidatively, and a step 2 of refluxing all or a part of a resultant decomposition gas to the polymer film production furnace.

A high-adsorption-performance nanofiber filter medium includes a support material and a composite nanofiber filtration layer that includes multiple nanometer composite nanofiber layers deposited and stacked on the support material. The nanometer composite nanofiber layer includes first, second, and third nano-powder composite nanofibers, which are uniformly mixed by means of an airflow or are sequentially laminated to form the nanometer composite nanofiber layer. The nanometer composite nanofiber layer formed through sequential lamination includes first, second, and third nanofiber layers. The first nanofiber layer includes multiple first nano-powder composite nanofibers. The second nanofiber layer is stacked on the first nanofiber layer and includes multiple second nano-powder composite nanofibers. The third nanofiber layer is stacked on the second nanofiber layer and includes multiple third nano-powder composite nanofibers. The composite nanofiber filtration layer is formed of multiple nanometer composite nanofiber layers, so that the high-adsorption-performance nanofiber air filter medium shows improved performance.

A supported catalyst for decomposing an organic substance that includes a support and a catalyst particle supported on the support. The catalyst particle contains a perovskite-type composite oxide represented by A.sub.xB.sub.yM.sub.zO.sub.w, where the A contains at least one selected from Ba and Sr, the B contains Zr, the M is at least one selected from Mn, Co, Ni and Fe, y+z=1, x≥0.995, z≤0.4, and w is a positive value satisfying electrical neutrality. A film thickness of a catalyst-supporting film supported on the support and containing the catalyst particle is 5 μm or more, or a supported amount as determined by normalizing a mass of the catalyst particle supported on the support by a volume of the support is 45 g/L or more.