Abstract: Disclosed are a grain boundary and surface-doped rare earth zirconium-based ceramic material and a preparation method and application thereof, and part of doped elements are positioned at the grain boundary and surface of the rare earth zirconium-based ceramic material by a step-by-step doping method. The sintering activity of the rare earth zirconium-based ceramic material can be changed by adjusting the type and content of doping elements at the grain boundary and the surface, thereby enabling the control of the grain size and the grain boundary number and characteristics of the rare earth zirconium-based ceramic material, and finally optimizing the properties, such as electrical and mechanical properties, of the material. The doping method has the advantages of simple process, low cost and high universality, and can meet the requirements of different rare earth zirconium-based ceramics on doping elements, and thus is suitable for large-scale application.

Abstract: Disclosed are a grain boundary and surface-loaded noble metal catalyst, a preparation method and an application thereof. The noble metal is dispersed at the grain boundary and surface of alumina and/or a rare earth manganese-zirconium composite oxide to form a multiphase interface, which achieves the following beneficial technical effects: firstly, the multiphase interface has a larger steric hindrance and a stronger anchoring effect, which can inhibit the migration, agglomeration, and growth of the noble metal at high temperatures, increase the high-temperature stability and catalytic performance of the noble metal, and reduce the usage of the noble metal; secondly, the multiphase interface exhibits a synergistic catalytic effect, which can reduce the activation energy of lattice oxygen and increase the quantity of active oxygen, thereby enhancing the NO oxidation and low-temperature catalytic activity.

Abstract: Disclosed are a grain boundary- and surface-doped lithium-lanthanum-zirconium composite oxide solid electrolyte, a preparation method therefor, and an application thereof. Part of doping elements are step-doped at the grain boundary and the surface of the lithium-lanthanum-zirconium composite oxide solid electrolyte to improve the distribution state of the doping elements at the grain boundaries, reduce the number of grain boundaries, lower the grain boundary resistance of the lithium-lanthanum-zirconium composite oxide, thereby obtaining high ionic conductivity. The doping method has the advantages of being simple and convenient in process, low in cost and high in universality, can meet the requirements of different solid electrolytes on doping elements, and is suitable for large-scale application.

Abstract: 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 REcBaOb-(1-A)CexZr(1-x-y)MyO2-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 REcMnaOb, 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 CexZr(1-x-y)MyO2-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.

Abstract: The present disclosure provides a cerium-zirconium-based composite oxide with a core-shell structure and a preparation method thereof, a catalyst system using the cerium-zirconium-based composite oxide, a catalytic converter for purifying tail gas by using the catalyst system, and application of the catalyst system or the catalytic converter in motor vehicle exhaust purification, industrial waste gas treatment or catalytic combustion. In the present invention, the cerium-zirconium-based composite oxide with a core-shell structure oxygen storage material is prepared by a step-by-step precipitation method. On the one hand, yttrium and a part of zirconium and cerium are precipitated on a cerium-zirconium surface, where the post-precipitation of yttrium is to segregate yttrium ions (Y3+) on a grain boundary surface, thus reducing lattice surface energy, pinning the grain boundary surface, making the migration of the grain boundary surface difficult, controlling the growth of grains.

Abstract: The present disclosure relates to a cerium-zirconium-based composite oxide having gradient element distribution and a preparation method therefor. According to the present disclosure, the cerium-zirconium-based composite oxide having gradient element distribution is prepared by a step-by-step precipitation method. First, a zirconium-rich component is precipitated to form a crystal structure and a crystal grain stack structure which have high thermal stability, slow down the segregation of zirconium on a surface after high-temperature treatment, and reduce element migration among crystal grains; second, a cerium-rich component is precipitated to improve the cerium content of the surface layers of the crystal grains, improve the utilization rate of the cerium element, and improve the oxygen storage amount and the oxygen storage rate.

Abstract: 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 REcBaOb-(1-A)CexZr(1-x-y)MyO2-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 REcMnaOb, 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 CexZr(1-x-y)MyO2-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.

Abstract: The present invention provides a process for metallurgy and separating a rare earth concentrate using a combination method, the process including: treating the rare earth concentrate containing bastnaesite by using a method including roasting under an atmosphere, leaching with hydrochloric acids, and roasting with a sulfuric acid, wherein stepping acid leaching with low-concentration hydrochloric acids is controlled during the leaching with the hydrochloric acids so as to obtain a rare earth solution with a high concentration (150-250 g/L REO), such that a leaching rate of Ce reaches 60% or more, and the content of F? in a leaching liquor is reduced by aging; and rare earth is further recovered from a leach residue by roasting with the sulfuric acid and leaching with water, and the total yield of the rare earth reaches 95% or more.

Abstract: Disclosed is a method of recovering rare earth, aluminum and silicon from rare earth-containing aluminum-silicon scrap. The method comprises: S1, acid-leaching the rare earth-containing aluminum-silicon scrap with an inorganic acid aqueous solution to obtain a silicon-rich slag and acid leached solution containing rare earth and aluminum element; S2, adding an alkaline substance into the acid leached solution containing the rare earth and aluminum element and controlling a PH value of the acid leaching solution between 3.5 to 5.2, performing a solid-liquid separation to obtain a aluminum hydroxide-containing precipitate and a rare earth-containing solution filter; S3, reacting the aluminum hydroxide containing precipitate with sodium hydroxide to obtain sodium metaaluminate solution and aluminum-silicon slag, and preparing a rare earth compound product with the rare earth-containing filtrate.

Abstract: Disclosed is a method of recovering rare earth, aluminum and silicon from rare earth-containing aluminum-silicon scrap. The method comprises: S1, acid-leaching the rare earth-containing aluminum-silicon scrap with an inorganic acid aqueous solution to obtain a silicon-rich slag and acid leached solution containing rare earth and aluminum element; S2, adding an alkaline substance into the acid leached solution containing the rare earth and aluminum element and controlling a PH value of the acid leaching solution between 3.5 to 5.2, performing a solid-liquid separation to obtain a aluminum hydroxide-containing precipitate and a rare earth-containing solution filter; S3, reacting the aluminum hydroxide containing precipitate with sodium hydroxidee to obtain sodium metaaluminate solution and aluminum-silicon slag, and preparing a rare earth compound product with the rare earth-containing filtrate.