A method for collecting a heavy rare earth element from a heavy rare earth element-containing molten salt electrolysis residue and recycling the heavy rare earth element, the method includes: a step of mixing coarse particles of the molten salt electrolysis residue with a fluorinating material followed by firing, to fluorinate the coarse particles of the molten salt electrolysis residue; a step of pulverizing the coarse particles of the fluorinated molten salt electrolysis residue to obtain a powder of the molten salt electrolysis residue; and a step of mixing the powder of the molten salt electrolysis residue with R, an R-M alloy, or an R-M-B alloy (wherein R is one or more types of rare earth elements selected from the group consisting of Y, La, Ce, Nd, Pr, Sm, Gd, Dy, Tb, and Ho, M is a transition metal such as Fe or Co, and B is boron), heating and melting the mixture, separating a molten alloy from slag, and selectively extracting the heavy rare earth element into the molten alloy. Provided are a method for recycling a heavy rare earth element that is capable of efficiently recycling a heavy rare earth element that is rare in an alloy form similar to a product, and a method for recycling a rare earth magnet by using an alloy obtained by the recycling method.

A tribo-electrostatic separation process for beneficiation of bauxite minerals is disclosed. The process may include one or more steps of grinding, drying, de-agglomeration, air classification and electrostatic separation.

A tribo-electrostatic separation process for beneficiation of bauxite minerals is disclosed. The process may include one or more steps of grinding, drying, de-agglomeration, air classification and electrostatic separation.

The present invention provides a method for selective recovery of a valuable metal from a waste denitrification catalyst through alkali fusion, the method comprising the steps of: (a) adding an alkali metal to a waste denitrification catalyst, followed by mixing and alkali fusion, to generate a calcination product; (b) subjecting the calcination product to water-leaching to recover an alkali leachate and a residue; (c) adding a precipitator to the alkali leachate, followed by stirring, to recover calcium metavanadate (Ca(VO.sub.3).sub.2) or calcium tungstate (CaWO.sub.4) through precipitation; and (d) subjecting the recovered calcium tungstate to acid decomposition to prepare tungstic acid. Therefore, vanadium and tungsten can be recovered at high efficiency by a method in which a precipitator is added to a leachate, which is obtained by adding an excess amount of an alkali metal to a waste denitrification catalyst and carrying out calcination and water-leaching, and then a reaction rate is controlled.

A roasting furnace for processing ores or concentrates, preferably molybdenum-containing ores or concentrates is described. The roasting furnace contains at least one first rotary lifting system for the displacement of said arm along the axis direction, wherein said first rotary lifting system is a telescopic lifting system, and/or wherein a distance x between two consecutive said stages of said roasting furnace are at least 1.000 m, wherein said distance x is measured along the axis direction. The roasting furnace of has an improved processing capacity and/or a reduction in the number of halts, and consequently is more energy-efficient, more environmentally-friendly and more economically interesting.

A roasting furnace for processing ores or concentrates, preferably molybdenum-containing ores or concentrates is described. The roasting furnace contains at least one first rotary lifting system for the displacement of said arm along the axis direction, wherein said first rotary lifting system is a telescopic lifting system, and/or wherein a distance x between two consecutive said stages of said roasting furnace are at least 1.000 m, wherein said distance x is measured along the axis direction. The roasting furnace of has an improved processing capacity and/or a reduction in the number of halts, and consequently is more energy-efficient, more environmentally-friendly and more economically interesting.

A method for recovering lithium from lithium ion battery scrap according to this invention comprises subjecting lithium ion battery scrap to a calcination step, a crushing step, and a sieving step sequentially carried out, wherein the method comprises, between the calcination step and the crushing step, between the crushing step and the sieving step, or after the sieving step, a lithium dissolution step of bringing the lithium ion battery scrap into contact with water and dissolving lithium contained in the lithium ion battery scrap in the water to obtain a lithium-dissolved solution; a lithium concentration step of solvent-extracting lithium ions contained in the lithium-dissolved solution and stripping them to concentrate the lithium ions to obtain a lithium concentrate; and a carbonation step of carbonating the lithium ions in the lithium concentrate to obtain lithium carbonate.

A method for recovering lithium from lithium ion battery scrap according to this invention comprises subjecting lithium ion battery scrap to a calcination step, a crushing step, and a sieving step sequentially carried out, wherein the method comprises, between the calcination step and the crushing step, between the crushing step and the sieving step, or after the sieving step, a lithium dissolution step of bringing the lithium ion battery scrap into contact with water and dissolving lithium contained in the lithium ion battery scrap in the water to obtain a lithium-dissolved solution; a lithium concentration step of solvent-extracting lithium ions contained in the lithium-dissolved solution and stripping them to concentrate the lithium ions to obtain a lithium concentrate; and a carbonation step of carbonating the lithium ions in the lithium concentrate to obtain lithium carbonate.

The present invention relates to a method for recovering nickel and cobalt from a nickel, iron, and cobalt-containing raw material. According to the present invention, high concentrations of valuable metals, such as nickel and cobalt, can be recovered from a raw material containing nickel, iron, and cobalt, and especially, the concentrations of nickel and cobalt are low and the concentration of iron is high, and thus when nickel is leached, and relatively large amount of iron is leached, whereas a small amount of nickel is leached. Therefore, the present invention can be more suitably applied in the smelting of nickel ore in which the separation of iron and nickel is difficult.

Provided are: an alloy powder that can be obtained from a waste lithium ion battery, wherein the alloy powder can be dissolved in an acid solution and enables recovery of metals contained in the alloy powder; and a method for producing the alloy powder. This alloy powder contains Cu and at least one of Ni and Co as constituent components, wherein a portion having a higher concentration of the at least one of Ni and Co than the average concentration in the entire alloy powder is distributed on at least the surface, and the phosphorus grade is less than 0.1% by mass. The method for producing the alloy powder includes a powdering step for powdering a molten alloy using a gas atomization method, the molten alloy containing Cu and at least one of Ni and Co as constituent components and having a phosphorus grade of less than 0.1% by mass.