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. The method dissolves an the aluminum and the rare earth with the acid and then via step wise alkaline conversion, convert aluminum icons to an aluminum hydroxide precipitate separated from rare earth ions, and then adds excessive amounts of sodium hydroxide to convert the aluminum hydroxide to a sodium metaaluminate solution, thereby realizing high-efficiency recovery of both rare earth and aluminum while significantly reducing the consumption of the sodium hydroxide and thus recovery cost.

A composite extractant-enhanced polymer resin comprising an extractant and a polymer resin for direct extraction of valuable metals such as rare earth metals, and more specifically, scandium, from an acid-leaching slurry and/or acid-leaching solution in which ferric ions are not required to be reduced into ferrous ions. The extractant may be cationic, non-ionic, or anionic. More specifically, the extractant di(2-ethylhexyl)phosphoric acid may be used. The polymer resin may be non-functional or have functional groups of sulfonic acid, carboxylic acid, iminodiacetic acid, phosphoric acid, or amines. The composite extractant-enhanced polymer resin may be used for extraction of rare earth metals from acid-leaching slurries or solutions.

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. The method dissolves an the aluminum and the rare earth with the acid and then via step wise alkaline conversion, convert aluminum icons to an aluminum hydroxide precipitate separated from rare earth ions, and then adds excessive amounts of sodium hydroxide to convert the aluminum hydroxide to a sodium metaaluminate solution, thereby realizing high-efficiency recovery of both rare earth and aluminum while significantly reducing the consumption of the sodium hydroxide and thus recovery cost.

Mixed rare earth carbonate may be prepared by mixing a rare earth sulfate solution with a precipitating agent comprising a first sodium carbonate (Na.sub.2CO.sub.3) solution, to form a first mixture, and generating a higher sulfate rare earth carbonate wet cake from the first mixture. The higher sulfate rare earth carbonate wet cake can be mixed with a second sodium carbonate (Na.sub.2CO.sub.3) solution to form a second mixture, and a lower sulfate rare earth carbonate can be generated from the second mixture.

Mixed rare earth carbonate may be prepared by mixing a rare earth sulfate solution with a precipitating agent comprising a first sodium carbonate (Na.sub.2CO.sub.3) solution, to form a first mixture, and generating a higher sulfate rare earth carbonate wet cake from the first mixture. The higher sulfate rare earth carbonate wet cake can be mixed with a second sodium carbonate (Na.sub.2CO.sub.3) solution to form a second mixture, and a lower sulfate rare earth carbonate can be generated from the second mixture.

An object of the present invention is to provide a method useful for separating a light rare earth element and a heavy rare earth element, which, for example, when a light rare earth element and a heavy rare earth element are separated from a workpiece containing a light rare earth element and a heavy rare earth element by a solvent extraction method, makes it possible to reduce the amount of extractant or organic solvent used or downsize the apparatus, or makes it possible to reduce the work burden on the process, such as the analysis of the content ratio between the light rare earth element and the heavy rare earth element contained in the workpiece. The method of the present invention as a means for resolution is characterized by including at least: (1) a step of obtaining, from a workpiece containing a light rare earth element and a heavy rare earth element, a composite oxide or mixture of oxides of the two; (2) a step of dissolving the obtained composite oxide or mixture of oxides of a light rare earth element and a heavy rare earth element in hydrochloric acid and/or nitric acid; (3) a step of adding a precipitant to the obtained solution to give a precipitate; (4) a step of calcining the obtained precipitate; (5) a step of adding the obtained calcine in an amount of 1.1 times to 3.0 times the upper solubility limit to hydrochloric acid and/or nitric acid having a concentration of 0.7 mol/L or more to give a solution and a residue; and (6) a step of separating the obtained solution and residue, thereby giving the solution as a light rare earth element-rich inclusion and the residue as a heavy rare earth element-rich inclusion (here, the term rich means that the content ratio of the concerned rare earth element to the other rare earth element is higher than the content ratio in the workpiece).

The present invention relates to a process for purifying and concentrating rare earths contained in phosphogypsum, characterised in that it comprises the following steps of: from a phosphogypsum, a) Leaching the phosphogypsum with a solution of one or more strong acid(s) selected from among: sulphuric acid, nitric acid and hydrochloric acid, in order to obtain a leaching mixture comprising a liquid phase formed by a leaching solution containing rare earths from the phosphogypsum and the leaching acid, and a solid phase comprising the phosphogypsum, b) Adding, to the phosphogypsum, an oxidising agent to promote passage of the rare earths from the phosphogypsum into the leaching solution, and/or a reducing agent to reduce solubility of mineral impurities contained in the leaching solution in order to allow their passage from the leaching solution into the solid phase, c) Separating the liquid phase enriched in rare earths and depleted in mineral impurities, and the solid phase enriched in mineral impurities.

The present invention relates to a process for purifying and concentrating rare earths contained in phosphogypsum, characterised in that it comprises the following steps of: from a phosphogypsum, a) Leaching the phosphogypsum with a solution of one or more strong acid(s) selected from among: sulphuric acid, nitric acid and hydrochloric acid, in order to obtain a leaching mixture comprising a liquid phase formed by a leaching solution containing rare earths from the phosphogypsum and the leaching acid, and a solid phase comprising the phosphogypsum, b) Adding, to the phosphogypsum, an oxidising agent to promote passage of the rare earths from the phosphogypsum into the leaching solution, and/or a reducing agent to reduce solubility of mineral impurities contained in the leaching solution in order to allow their passage from the leaching solution into the solid phase, c) Separating the liquid phase enriched in rare earths and depleted in mineral impurities, and the solid phase enriched in mineral impurities.

A mesoporous cerium oxide nano-material and a preparation method and an application thereof are provided in the present disclosure, belonging to the technical field of porous materials. The preparation method includes the following steps: using porous organic frameworks material as a templating agent, impregnating and adsorbing cerium salt precursor under an action of alkali, and removing the templating agent by roasting pyrolysis to obtain the mesoporous cerium oxide nano-material. POFs is carbonized into mesoporous carbon materials by calcination in inert atmosphere, which supports the mesoporous channels of cerium oxide, and then the carbonized carbon materials of POFs are removed by calcination in air atmosphere, forming the mesoporous structure of cerium oxide. The mesoporous cerium oxide nano-material prepared by the present disclosure has a high specific surface area and mesoporous structure, and is used as a catalytic material or catalyst carrier.

A mesoporous cerium oxide nano-material and a preparation method and an application thereof are provided in the present disclosure, belonging to the technical field of porous materials. The preparation method includes the following steps: using porous organic frameworks material as a templating agent, impregnating and adsorbing cerium salt precursor under an action of alkali, and removing the templating agent by roasting pyrolysis to obtain the mesoporous cerium oxide nano-material. POFs is carbonized into mesoporous carbon materials by calcination in inert atmosphere, which supports the mesoporous channels of cerium oxide, and then the carbonized carbon materials of POFs are removed by calcination in air atmosphere, forming the mesoporous structure of cerium oxide. The mesoporous cerium oxide nano-material prepared by the present disclosure has a high specific surface area and mesoporous structure, and is used as a catalytic material or catalyst carrier.