Proposed is a multi-layer filtration system including a metal catalyst filter unit, a carbon filter unit, and an inorganic compound filter unit. The metal catalyst filter unit includes at least one among metals including Ni, Co, Fe, Cu, Cr, Mg, Zn, Ba, Au, Ag, Pd, Pt, Ru, Mn, and Ti, oxides thereof, and mixtures thereof. The carbon filter unit includes at least one of activated carbon or activated carbon fiber. The inorganic compound filter unit includes an inorganic compound capable of adsorbing toxic gas. The multi-layer filtration system has good removal effect for toxic gas. A filter module including the multi-layer filtration system and a gas mask including the multi-layer filtration system are also proposed.

A catalyst for catalytic oxidation-deoxidation method of unsaturated hydrocarbon-containing gas has a carrier, an active component, a first co-agent component, and a second co-agent component loaded on the carrier respectively. The active component is one or more selected from the group consisting of oxides of Pt, Pd, Ru, Rh, Ag and Ir. The first co-agent component has one or more selected from the group consisting of a rare earth metal element, a group IVB metal element and a group VIII metal element; and the second co-agent component has one or more alkali metal element and alkaline earth metal element. The deoxidation method using the catalyst eliminates the need to add a reducing gas such as H.sub.2, allows hydrocarbons to react directly with oxygen to produce CO.sub.2 and H.sub.2O, achieves the goal of deoxidating a hydrocarbon-containing tail gas, and can prevent the generation of carbon deposits.

A method for preparing an active catalyst for high-efficiency denitration is disclosed. The method includes: a catalyst raw material is charged into a denitration reactor, NH.sub.3 and an inert gas are introduced and then heating is performed, and the temperature is held and then natural cooling is performed, thereby obtaining the catalyst. The active catalyst can greatly improve the denitration activity in low temperature range, and can not only improve the denitration efficiency under the condition without SO.sub.2 and H.sub.2O, but also can improve the denitration efficiency under the condition with both SO.sub.2 and H.sub.2O. The service life of the catalyst is prolonged under the premise of not changing the existing catalyst preparation process, and the economic benefit is significant. The denitration efficiency of a powder catalyst can be increased by 25%, and the denitration efficiency of a honeycombed catalyst or a corrugated catalyst can be increased by 20%.

The present disclosure relates to a carbon dioxide capture device comprising a first reactor and a second reactor both of which show a (photo)anode containing or connected to oxygen evolution and/or carbon dioxide evolution catalyst(s) and a (photo)cathode containing or connected to an oxygen reduction catalyst, wherein the first reactor comprises an anion exchange membrane placed between the porous (photo)anode and porous (photo)cathode, and the second reactor comprises a proton exchange membrane placed between the porous (photo)anode and porous (photo)cathode. On the porous (photo)cathode side of the first reactor there is a fluid inlet able to carry carbon dioxide, air and water, and on the side of the porous (photo)cathode of the second reactor there is a fluid outlet able to carry carbon dioxide and water.

A powdered catalyst material on a titanium oxide basis. The powdered catalyst material includes a combined content of at least 90 wt.-% of a hydrated titanium oxide having the general formula TiO.sub.(2-x)(OH).sub.2x, with 0<x≤1, (calculated as TiO.sub.2), and a silicon dioxide and hydrated precursors of the silicon dioxide (calculated as SiO.sub.2). A weight ratio of TiO.sub.2/SiO.sub.2, determined for TiO.sub.2 and SiO.sub.2 respectively, is at least 3 and less than 30. The wt.-% is based on a total weight of the catalyst material after the catalyst material has been dried at 105° C. for at least 2 hours. The powdered catalyst material has a specific surface area of >300 m.sup.2/g and an isoelectric point of from 4.0 to 7.0.

Disclosed herein are methods, systems, and compositions for providing catalysts for tail gas clean up in sulfur recovery operations. Aspects of the disclosure involve obtaining catalyst that was used in a first process, which is not a tailgas treating process and then using the so-obtained catalyst in a tailgas treating process. For example, the catalyst may originally be a hydroprocessing catalyst. A beneficial aspect of the disclosed methods and systems is that the re-use of spent hydroprocessing catalyst reduces hazardous waste generation by operators from spent catalyst disposal. Ultimately, this helps reduce the environmental impact of the catalyst life cycle. The disclosed methods and systems also provide an economically attractive source of high-performance catalyst for tailgas treatment, which benefits the spent catalyst generator, the catalyst provider, and the catalyst consumer.

Embodiments of the invention include a filtration element. In an embodiment, the invention includes a filtration element for an airplane cabin that includes a first media portion upstream from a second media portion. The first media portion can include activated carbon. The second media portion can include a catalyst material. Other embodiments are also included herein.

Process for preparing a catalyst or a trapping mass comprising the following steps: bringing a porous oxide support into contact with a metal salt comprising at least one metal belonging to groups VIB, VIIB, VIIIB, IB or IIB, of which the melting point of said metal salt is between 20° C. and 150° C., for a period of between 5 minutes and 5 hours in order to form a solid mixture, the weight ratio of said metal salt to said porous oxide support being between 0.1 and 1; heating the solid mixture with stirring at a temperature between the melting point of said metal salt and 200° C. and for 5 minutes to 12 hours; calcining the solid obtained in the preceding step at a temperature above 200° C. and below or equal to 1100° C. under an inert atmosphere or under an oxygen-containing atmosphere.

Manganese-cobalt (Mn—Co) spinel oxide nanowire arrays are synthesized at low pressure and low temperature by a hydrothermal method. The method can include contacting a substrate with a solvent, such as water, that includes Mn04- and Co2 ions at a temperature from about 60° C. to about 120° C. The method preferably includes dissolving potassium permanganate (KMn04) in the solvent to yield the Mn04- ions. the substrate is The nanoarrays are useful for reducing a concentration of an impurity, such as a hydrocarbon, in a gas, such as an emission source. The resulting material with high surface area and high materials utilization efficiency can be directly used for environment and energy applications including emission control systems, air/water purifying systems and lithium-ion batteries.

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).