A method for cleaning an off-gas from viscose production, essentially containing H.sub.2S and CS.sub.2, comprises passing the gas through a catalytic reactor containing a direct oxidation type catalyst, such as V.sub.2O.sub.5 on silica, to convert H.sub.2S in the gas to elemental sulfur, SO.sub.2 or mixtures thereof, either via the oxygen present in the gas or via oxygen added to the gas stream. Elemental sulfur and SO.sub.2 are removed from the effluent gas from the catalytic reactor, and the unconverted CS.sub.2 is recycled to the viscose production process.

A porous material includes an aggregate, and a binding material that binds the aggregate together in a state where pores are formed. The porous material contains 0.1 to 10.0 mass % of an MgO component, 0.5 to 25.0 mass % of an Al.sub.2O.sub.3 component, and 5.0 to 45.0 mass % of an SiO.sub.2 component with respect to the mass of the whole porous material, and further contains 0.01 to 5.5 mass % of an Sr component in terms of SrO.

A method for making a catalyst for ozone decomposition includes: adding a reducing agent into a water solution of a permanganate salt to obtain a first reaction liquid, and heating the first reaction liquid under continuous stirring to form a birnessite-type manganese dioxide; and adding the birnessite-type manganese dioxide into a water solution of an ammonium salt to obtain a second reaction liquid, and heating the second reaction liquid under continuous stirring to form the catalyst.

A built-in apparatus and method for treating air including a housing with an air inlet and an air outlet. An air mover positioned near the air outlet is configured to draw the air through the air inlet. The housing encloses an air treatment zone, such as including an oxidizing zone, and an ozone removal zone positioned downstream of the air treatment zone and oxidizing zone. The air treatment zone includes UV light and/or ozone that partially oxidizes the chemical contaminants in the air treatment zone. A catalyst in the oxidizing zone oxidizes elements within the air treatment zone. The ozone removal zone includes a second, different catalyst material. A UV bulb that may or may not generate ozone is positioned within or downstream of the first and/or second catalyst materials to assist catalyst oxidation and/or self-clean the apparatus.

Catalyst for oxygen storage capacity applications that include a zinc doped manganese-iron spinel mixed oxide material. The zinc doped manganese-iron spinel mixed oxide material may be synthesized by a co-precipitation method using a precipitation agent such as sodium carbonate and exhibits a high oxygen storage capacity.

The present invention relates to a metallic nanoparticle catalyst, and more particularly, to a porous catalyst in which metallic nanoparticles are embedded in a porous oxide support, and a method for preparing the porous catalyst. To this end, a porous catalyst composition having metallic nanoparticles of the present invention includes an oxide matrix structure having mesopores and micropores; and metal or metal oxide nanoparticles embedded in the oxide matrix structure having the mesopores and micropores. Thus, metallic nanoparticle catalysts having high activity even at low temperature are realized.

An oxygen storage material (OSM) includes a zinc manganese iron oxide (ZMF) and an alkali metal base on the ZMF surface. The ZMF has a spinel structure. The alkali metal containing ZMF can be formed to have a weight percent of alkali metal up to about two percent. The alkali metal carbonate is retained on the ZMF surface upon heating to a temperature greater than 1,000° C. and stabilizes the ZMF to the cycling of an oxygen rich and oxygen lean atmosphere. The OSM additionally catalyzes the oxidation of hydrocarbons and CO and catalyzes the reduction of NO.sub.x for use in catalytic converters.

The invention provides a solid material for air purification and disinfection and a preparation method and application thereof. The solid material includes: 50-60 wt. % of inorganic porous materials, 10-20 wt. % of nano titanium dioxide, 3-5 wt. % of fluorescent materials, 20-30 wt. % of sodium chlorite, 3-5 wt. % of sodium lignosulfonate, 1-10 wt. % of polyethylene glycol, and 1-10 wt. % of polyvinyl alcohol. The method for preparing the solid material includes: formulating the fluorescent material into a slurry by using a polyethylene glycol aqueous solution; uniformly mixing the nano titanium dioxide, the sodium lignosulfonate, and the fluorescent material formulated into the slurry, and then spraying the mixture on an inorganic porous material carrier to be uniformly adsorbed; and mixing the sodium chlorite with the above mixture for granulation to obtain the product. The solid material for air purification of the invention can be stored stably for a long time, and chlorine dioxide gas slowly released can degrade harmful substances in the air such as formaldehyde and kill bacteria in the air.

An oxygen storage material (OSM) includes a zinc manganese iron oxide (ZMF) and an alkali metal base on the ZMF surface. The ZMF has a spinel structure. The alkali metal containing ZMF can be formed to have a weight percent of alkali metal up to about two percent. The alkali metal carbonate is retained on the ZMF surface upon heating to a temperature greater than 1,000° C. and stabilizes the ZMF to the cycling of an oxygen rich and oxygen lean atmosphere. The OSM additionally catalyzes the oxidation of hydrocarbons and CO and catalyzes the reduction of NO.sub.x for use in catalytic converters.

A process of reducing the content of nitrogen oxides in a gas, comprising passing the gas over a catalyst suitable for selective catalytic reduction of nitrogen oxides and in the presence of a reducing agent, wherein the catalyst is a FER-zeolite obtainable with a process which does not include a step of iron loading and does not include a step of loading with any transition metal so that said FER-zeolite does not contain ion-exchanged iron and is not loaded with iron or any transition metal.