The present invention discloses a rare-earth-manganese/cerium-zirconium-based composite compound, a method for preparing the same, and a use thereof. The composite compound is of a core-shell structure with a general formula expressed as: A RE.sub.cB.sub.aO.sub.b-(1-A)Ce.sub.xZr.sub.(1-x-y)M.sub.yO.sub.2-z, wherein 0.1≤A≤0.3, preferably 0.1≤A≤0.2; a shell layer has a main component of rare-earth manganese oxide with a general formula of RE.sub.cMn.sub.aO.sub.b, wherein RE is a rare-earth element or a combination of more than one rare-earth elements, and B is Mn or a combination of Mn and a transition metal element, 1≤a≤8, 2≤b≤18, and 0.25≤c≤4; and a core has a main component of cerium-zirconium composite oxide with a general formula of Ce.sub.xZr.sub.(1-x-y)M.sub.yO.sub.2-z, wherein M is one or more non-cerium rare-earth elements, 0.1≤x≤0.9, 0≤y≤0.3, and 0.01≤z≤0.3. The composite compound enhances an oxygen storage capacity of a cerium-zirconium material through an interface effect, thereby increasing a conversion rate of a nitrogen oxide.

Various uses of monochlorotrifluoropropenes, in combination with one or more other components, including other fluoroalkenes, hydrocarbons; hydrofluorocarbons (HFCs), ethers, alcohols, aldehydes, ketones, methyl formate, formic acid, water, trans-1,2-dichloroethylene, carbon dioxide and combinations of any two or more of these, in a variety of applications, including as blowing agents, are disclosed.

A process is disclosed comprising, providing a source of graphene, providing a particulate material, dispersing a mixture of the source of graphene and the particulate material in a first dispersion fluid to form a dispersion mixture, and providing a source of a base in the first dispersion fluid, thereby causing the source of graphene and particulate material in the dispersion mixture to interact forming a composite. The particulate material is preferably titanium dioxide comprising anatase and/or rutile which provides an effective photocatalytic composite. Also disclosed is apparatus to remove pollutants from fluids using the photocatalytically active material.

The present invention provides a process for preparing a catalyst precursor, said process comprising the steps of (i) providing Pt.sub.aX.sub.b alloy particles on a support material and (ii) applying a shell of X to the Pt.sub.aX.sub.b alloy particles to provide a catalyst precursor comprising particles having a Pt.sub.aX.sub.b core and an X shell. The ratio of a to b is in the range of and including 10:1 to 1:2.5 and X is Co, Ni, Y, Gd, Sc or Cu. Also provided is a process for preparing a catalyst material.

The invention relates to tetraalkylammonium-tetra- or hexahydroxometallates such as tetraethylammonium hexahydroxoplatinate, (N(alkyl)4)y[M(OH)x], a method for the production thereof, and the use thereof for producing catalysts.

A method for preparing carbon-functionalized praseodymium oxide includes the following steps: dissolving Pr(NO.sub.3).sub.3.6H.sub.2O in an acid dye solution and stirring to form a mixed solution; adding NH.sub.3H.sub.2O dropwise in the mixed solution while stirring to adjust a pH value of the mixed solution, thereby forming a suspension, and then aging the suspension for 2 to 4 hours; filtering, washing with water, washing with alcohol, and drying the aged suspension to obtain a carbon-functionalized Pr.sub.6O.sub.11 precursor; and placing the carbon-functional zed Pr.sub.6O.sub.11 precursor in a tube furnace under a protection of nitrogen, heating the carbon-functionalized Pr.sub.6O.sub.11 precursor to a sintering temperature at a heating rate of 4 to 6 degrees Celsius/min, keeping at the sintering temperature for 3 to 4 hours, and then cooling to room temperature, thereby obtaining the carbon-functionalized. Pr.sub.6O.sub.11.

The present invention relates to a metal oxide coated composite comprising a core consisting of a mixture of a La stabilized Al.sub.2O.sub.3 phase and an Ce/Zr/RE.sub.2O.sub.3 mixed oxide phase, the core having a specific crystallinity, specific pore volume and a specific pore size distribution, and a method for the production of the metal oxide coated composite.

A calcium silicate based nickel catalyst and a preparation method and application thereof are provided. The method includes: leaching a silicon based solid waste with an alkali agent to obtain a silicate leaching solution; adding the silicate leaching solution and a nitrate solution corresponding to a lanthanum metal dropwise to a calcium hydroxide suspension for a first precipitation reaction, and subjecting a precipitate produced by the reaction to filtration, drying and calcination to obtain a modified calcium silicate support; and dispersing the modified calcium silicate support in an anhydrous alcohol solvent to obtain a mixed suspension, adding an alcohol solution of a nickel salt dropwise to the mixed suspension for a second precipitation reaction, conducting heating and stirring until alcohols in the anhydrous alcohol solvent and the alcohol solution of a nickel salt are volatilized, and conducting drying and calcination to obtain the modified calcium silicate based nickel catalyst.

A catalyst suitable for use in carbon oxide conversion reactions is described, said catalyst in the form of a shaped unit formed from an oxidic catalyst powder, said catalyst comprising 30-70% by weight of copper oxide, combined with zinc oxide, alumina and silica, having a Si:AI atomic ratio in the range 0.005 to 0.15:1, and having a BET surface area >105 m.sup.2/g and a copper surface area >37 m.sup.2/g catalyst. The catalyst is prepared by a co-precipitation method using an alumina sol.

A glass fiber filter element for visible light photocatalysis and air purification and a method for preparing the same. The glass fiber filter element includes 4 to 7 wt % of nanoparticles including at least one selected from zinc oxide, graphene oxide, titanium oxide, and reduced graphene oxide, 2 to 7 wt % of silver nanowires, 3 to 12 wt % of an adhesive system, and 78 to 91 wt % of a glass fiber mat, based on the total weight of the glass fiber filter element. The glass fiber mat is made of at least two glass fibers with different diameters, and the diameters are in a range of 0.15 to 3.5 μm. The nanoparticles have a particle size from 1 to 200 nm, and the silver nanowires have a diameter of 15 to 50 nm.