A method of recovering a cathode active material precursor according to an embodiment of the present invention includes preparing a cathode active material mixture including a lithium composite oxide, separating lithium from the cathode active material mixture to form a preliminary transition metal precursor, acid-treating the preliminary transition metal precursor to form a complex transition metal salt solution, and adding an acidic extractant to the complex transition metal salt solution and then adding a basic compound to recover a transition metal precursor, and thus the extraction rate of transition metals can be improved.

In a method for recovering active metals from a lithium secondary battery according to exemplary embodiments, a cathode active material mixture including a lithium composite oxide may be reacted with a reducing reaction gas under a pressurized condition and washed with water. In this case, a large amount of the cathode active material mixture may be treated within a shortened process time, and the active metal may be recovered with high yield and high efficiency.

The present disclosure provides a method for co-extraction of vanadium, titanium and chromium from vanadium slag. The method selectively reduces pyroxene and fayalite wrapped on spinel through low-temperature hydrogen reduction, iron removal by ferric chloride, and low-temperature leaching of the vanadium slag by oxalic acid, thereby destroying a structure of the spinel, dissociating a spinel phase and a silicate phase, and fully exposing the spinel phase. The method also directly leaches the vanadium slag at a low temperature by acidity and strong complexation of the oxalic acid, and destroys the structure of the spinel, such that vanadium, titanium, chromium and oxalate are complexed into a solution to co-extract vanadium, titanium and chromium. The present disclosure extracts vanadium, titanium and chromium from the vanadium slag, with a leaching rate each being greater than 99%.

A method of recovering substantially rare earth elements (REEs) from magnets, including first dissolving a magnet to yield a solution containing Nd, Pr, and Dy, and then equilibrating a first column with Cu2+ solution to yield a first equilibrated column, introducing the solution to the first equilibrated column, and introducing a ligand solution to the first equilibrated column to establish three bands of different liquid compositions in the column, wherein the three bands comprise a Dy/Nd mixed band, a first pure Nd band, and a Nd/Pr mixed band. Next, sending the Dy/Nd mixed band to a second column containing a Cu2+ solution and introducing a ligand solution to the second column to establish a pure Dy band and a second pure Nd band in the second column, and sending the Nd/Pr mixed band to a third column containing a Cu2+ solution and introducing a ligand solution to the third column to establish a third pure Nd band and a pure Pr band in the third column. Finally, eluting the respective pure Nd bands to recover Nd, eluting the pure Dy band to recover Dy, and eluting the pure Pr band to recover Pr.

A process for recovering a metal in the form of a metal halide from a metal-containing source is described, the process comprising the steps of: —(i) forming a solid metal halide containing product by contacting the metal-containing source with a gaseous halide in an oxidising environment and at a temperature below the vaporisation temperature of the metal halide of interest; (ii) heating the metal halide containing product formed in step (i) to a temperature at or above the vaporisation temperature of the metal halide to form a gaseous metal halide containing product; and (iii) condensing the gaseous metal halide containing product of step (ii) to recover the metal halide of interest.

The purpose is to provide a method for recovering a valuable metal at low cost. The present invention is a method for recovering a valuable metal, the method comprising a step of preparing a burden material containing at least a valuable metal to obtain a raw material, a step of subjecting the raw material to an oxidation treatment and a reductive melting treatment to produce a reduced product containing an alloy and a slag, and a step of separating the slag from the reduced product to collect the alloy, in which the copper grade, which is a ratio of the mass of copper (Cu) to the total mass of nickel (Ni), cobalt (Co) and copper (Cu) contained in the alloy (i.e., a Cu/(Ni+Co+Cu) ratio), is adjusted to 0.250 or more.

A hydrometallurgical method for simultaneously extracting zinc, lead, silver, iron and calcium from electric arc furnace dust (hazardous waste) produced by the steelmaking industry (steelworks), in the form of industrial products: zinc as zinc sulphate or zinc cathodes; lead and silver as a concentrate of lead and silver; iron as reduced elemental iron for return to the electric arc furnace; and, lastly, calcium as gypsum, without solid waste or liquid effluents being generated relates to the chemical nature of the electric arc furnace dust (complex oxides) changes to a sulfide complex, and eliminating the hazards associated with the generation of fugitive heavy-metal salts. In addition, the hydrometallurgical problem of low recovery of zinc and iron is solved. Consequently, hydrometallurgy is made easier and more environmentally friendly, as condensed water is used as a leachate, the condensed water being continuously regenerated by vacuum evaporation systems without generating effluents.

A method for recovering Vanadium from a secondary source such as fly ash. Leaching is involved using single or combined acids such as hydrochloric and sulfuric in a temperature range of 20° C. and 100° C. The leaching is performed in sequential operations with recovery of Vanadium in the range of 92%. The recovered Vanadium can be formulated into an electrolyte for redox batteries

Process for reducing hexavalent chromium in oxidic solids, which comprises the steps: a) mixing of the oxidic solid containing Cr(VI) with a carbon-containing compound which is liquid in the range from 20 to 100° C., b) treatment of the mixture obtained after a) in an indirectly heated reactor at a temperature of from 700° C. to 1100° C., particularly preferably at a temperature of from 800° C. to 1000° C., under a protective atmosphere, c) cooling of the reaction product obtained after b) to at least 300° C., preferably at least 150° C., under a protective atmosphere.

A method for recovering lithium oxide from lithium manganese oxide (LMO) includes producing lithium oxide (Li.sub.2O) via thermal reaction of lithium manganese oxide (LMO) in an hydrogen atmosphere, and performing water leaching of the produced lithium oxide to separate the lithium oxide from other products.