Provided is a separation recovery method of metal ions and a two-phase separated fluid. The separation recovery method includes mixing a water phase including two or more kinds of metal ions and an organic compound with an oil phase including an extractant to move metal ions belonging to Group 8 to Group 12 from the water phase to the oil phase, the two or more kinds of metal ions including metal ions belonging to Group 3 to Group 16, and the organic compound coordinated to at least one kind of metal ions among the metal ions. In the two-phase separated fluid, a water phase including two or more kinds of metal ions including metal ions belonging to Group 3 to Group 16 and an organic compound and an oil phase including an extractant are phase-separated and present, and metal ions where the extractant is coordinate-bonded to metal elements belonging to Group 8 to Group 12 are present in the oil phase.

Provided is a separation recovery method of metal ions and a two-phase separated fluid. The separation recovery method includes mixing a water phase including two or more kinds of metal ions and an organic compound with an oil phase including an extractant to move metal ions belonging to Group 8 to Group 12 from the water phase to the oil phase, the two or more kinds of metal ions including metal ions belonging to Group 3 to Group 16, and the organic compound coordinated to at least one kind of metal ions among the metal ions. In the two-phase separated fluid, a water phase including two or more kinds of metal ions including metal ions belonging to Group 3 to Group 16 and an organic compound and an oil phase including an extractant are phase-separated and present, and metal ions where the extractant is coordinate-bonded to metal elements belonging to Group 8 to Group 12 are present in the oil phase.

The invention relates to a process for recycling lithium salts contained in the electrolyte of a used lithium battery, which involves supplying an electrolyte stream comprising at least one lithium salt, at least one electrolyte solvent and water; at least one step of extracting the at least one lithium salt by adding a first solvent to the electrolyte stream to recover a phase comprising the at least one lithium salt on one side and a lithium salt-depleted phase on the other side.

The invention relates to a process for recycling lithium salts contained in the electrolyte of a used lithium battery, which involves supplying an electrolyte stream comprising at least one lithium salt, at least one electrolyte solvent and water; at least one step of extracting the at least one lithium salt by adding a first solvent to the electrolyte stream to recover a phase comprising the at least one lithium salt on one side and a lithium salt-depleted phase on the other side.

A method for processing lithium ion battery scrap according to this invention includes a leaching step of leaching lithium ion battery scrap to obtain a leached solution; an aluminum removal step of neutralizing the leached solution to a pH range of from 4.0 to 6.0, then performing solid-liquid separation and removing aluminum in the leached solution to obtain a first separated solution; and an iron removal step of adding an oxidizing agent to the first separated solution and adjusting the pH in a range of from 3.0 to 5.0, then performing solid-liquid separation and removing iron in the first separated solution to obtain a second separated solution.

The use of a synergistic mixture of extractants for extracting at least one rare earth element from an aqueous medium comprising phosphoric acid. The mixture comprises: a first extractant of formula (I): ##STR00001##
wherein R.sub.1 and R.sub.2, which are identical or different, represent a linear or branched, saturated or unsaturated hydrocarbon group, comprising from 6 to 12 carbon atoms, or a phenyl group optionally substituted by a linear or branched, saturated or unsaturated hydrocarbon group, comprising from 1 to 10 carbon atoms; anda second extractant of formula (II): ##STR00002##
in which R.sub.3 represents a linear or branched alkyl group, comprising from 6 to 12 carbon atoms. Use of the synergistic mixture in the treatment of phosphate minerals with a view to recovering the rare earth elements contained in the minerals.

A method for preparing an aqueous mineral suspension from an aqueous metal ore residue may include introducing into the aqueous metal ore residue a polymer (P) having a molecular mass Mw measured by GPC ranging from 2,000 to 20,000 g/mol. The polymer (P) may be prepared by radical polymerization of at least one anionic monomer (M). The suspension produced by such a method may have a Brookfield viscosity of which is lower than 1,800 mPa.Math.s or a yield point of lower than 80 Pa.

A method can prepare an aqueous mineral suspension from an aqueous metal ore residue into which there is introduced a polymer (P) having a molecular weight Mw measured by GPC of from 100,000 to 3.106 g/mol and prepared by free radical polymerization of at least one anionic monomer (m). The suspension produced may have a Brookfield viscosity greater than 2,000 mPa.Math.s and/or a flow threshold of greater than 40 Pa.

Provided is a method for recovering a precursor metal for secondary cell cathode material using synergistic solvent extraction applied with extractant degradation preventing technology including: (a) leaching a low grade MHP and sulfuric acid by high temperature and high pressure oxidation reaction; (b) separating a solution leached by the oxidation reaction and precipitant of an impurity containing iron (Fe); (c) recovering copper as copper sulfate solution by solvent extraction from the leached solution of (b); (d) precipitating and removing some impurities by injecting a neutralizing agent into a raffinate after solvent extraction of cooper in (c); and (e) recovering zinc, cobalt, and nickel from a solution from which some impurities are removed in (d) by means of the synergetic solvent extraction (SSX) to be selectively separated as a raffinate containing manganese, calcium, and magnesium.

Proposed are a positive electrode active material using a spent battery leachate for secondary batteries and a method of preparing the same. Using a spent battery leachate enables the positive electrode active material for secondary batteries, the positive electrode active material having a composition of Li(Ni.sub.aCo.sub.bAl.sub.c)O.sub.2 (where a+b+c=1) including Ni, Co, and Al and being prepared from a precursor having a composition of Ni.sub.aCo.sub.b (where a+b=1), to be prepared. As a result, some raw materials can be replaced with the spent battery leachate when preparing the positive electrode active material for secondary batteries, thereby reducing manufacturing costs and solving environmental problems.