Process for recovering cobalt, nickel and manganese ions from metal-containing residues

Abstract

The present invention provides a process for recovering one or more metal ions selected from the group consisting of cobalt, nickel, manganese, and mixtures thereof from a metal-containing residue, the process comprising the steps of: A) leaching the residue with a leach solution comprising lactic acid to obtain Filtrate 1 and Solid Cake 1; B) separating Filtrate 1; C) precipitating cobalt lactate, nickel lactate, or manganese lactate from Filtrate 1 to obtain Filtrate 2 and Precipitate 1; and D) separating Precipitate 1; or A) leaching the residue with a leach solution to obtain Filtrate 1 and Solid Cake 1; E) precipitating cobalt lactate, nickel lactate, or manganese lactate from Filtrate 1 to obtain Filtrate 3 and Solid Cake 2; F) separating Solid Cake 2; and G) separating cobalt lactate, nickel lactate, or manganese lactate from Solid Cake 2.

Description

[Technical Field]

[0001] This application claims the benefit of European Patent Application No. 20382720.9, filed August 3, 2020.

[0002] The present invention relates to a process for recovering cobalt, nickel and manganese ions from metal-containing residues (metal-containing waste), particularly batteries. In particular, the present invention relates to a process for recovering cobalt, nickel and manganese ions from residues, which comprises the use of lactic acid as a leaching agent and precipitant. [Background technology]

[0003] Disposal of metal-bearing residues has traditionally been primarily through landfilling, incineration, or deposition via pyrometallurgical processes, resulting in significant environmental pollution and low recovery rates of metallic materials. The most common metal-bearing residues are those derived from metallurgical industrial activities, such as alloys and metal catalysts, or from non-essential electronic devices, such as laptop and mobile phone batteries.

[0004] In particular, batteries are essential for energy storage in electronic devices used in our daily lives, from small portable electronic devices (PEDs) such as mobile phones and laptops to medical devices and electric vehicles (EVs).

[0005] Battery cells contain a wide variety of materials, including valuable metals (Li, Co, Ni, Mn, Cu, Al...), graphite, and organic compounds. Battery cells are generally made of plastic and function by the reversible transport of ions and electrons between an anode and a cathode separated by a porous membrane filled with an organic electrolyte containing additive salts. The anode and cathode consist of powders of the active electrode material (e.g., cobalt, nickel, manganese, and iron) mounted on current collecting foils (copper and aluminum).

[0006] The three most popular battery types are nickel-cadmium batteries, nickel-metal hydride batteries, and lithium-ion batteries. However, lithium-ion is the dominant battery technology adopted by the PED and EV industries and will account for most of the growth in global battery demand in the near future. These lithium-ion batteries, apart from lithium, contain several other raw materials such as cobalt, nickel, manganese, aluminum, and iron.

[0007] Future waste projections estimate a cumulative 4 million tons of end-of-life (EOL) EV battery modules by 2030, which exceeds current global recycling capacity. European legislation therefore stipulates that all collected used batteries must be treated and recycled. However, despite their continued widespread implementation, methods for recycling and reusing end-of-life (EOL) battery materials are still under development.

[0008] The processes for recycling commonly used batteries can be divided into three different types: mechanical, pyrometallurgical, and hydrometallurgical. Currently, on a commercial industrial scale, a combination of these processes is used to recover battery metal raw materials.

[0009] Recycling methods typically involve several steps. In the first initial stage, after collection and selection of the batteries, the cells are discharged (immersion in salt solutions) and mechanically treated (i.e., shredded or crushed, sieved, air, water bath, or magnetic separation). Breaking the battery structure yields a mixture of casing (steel), current collectors (Cu, Al), plastic separator, electrolyte, and active mass (AM) (i.e., LiCoO2). After this stage, the material is: Black MassThe BM is then converted into a black, crushed powder called BM (BM). The second stage can be a pyrometallurgical process. In actual industrial recycling processes, these processes are conventional processes involving three distinct steps: pyrolysis, reduction, and incineration. Finally, in the final stage, a hydrometallurgical process is applied. This step usually involves leaching the BM obtained in the last step to convert the substances present in the BM into new compounds through chemical reactions. The most commonly used leaching solutions contain inorganic acids such as sulfuric acid, hydrochloric acid, and nitric acid. Finally, a final precipitation can be performed to recover the original compounds of interest by adding a precipitating agent.

[0010] However, the recycling processes described above have several drawbacks. In particular, they have a significant negative impact on the environment due to the extreme experimental conditions and the use of hazardous and contaminated reagents. Furthermore, these processes cannot efficiently recycle all metallic materials present in used batteries, such as lithium, cobalt, nickel, manganese, and iron, especially nickel and cobalt.

[0011] Therefore, from what is known in the art, it follows that there remains a need to provide an environmentally friendly, easily industrially scalable, more efficient, safe and selective process for recycling metal-containing residues (e.g., spent batteries), in particular for recovering cobalt ions, nickel ions and manganese from the metal-containing residues. Summary of the Invention

[0012] The present inventors have provided an efficient process for selectively recovering the metal ions cobalt, nickel, and manganese from metal-containing residues, such as batteries. In particular, the present inventors have found that by using lactic acid as a leaching and precipitating agent, the recovery efficiency of cobalt, nickel, and manganese from metal-containing residues can be increased without compromising the selectivity for the remaining metal components of the residue. In particular, the process of the present invention makes it possible to have an extraction yield of more than 80% cobalt, more than 70% nickel, and more than 85% manganese in the first extraction pass.

[0013] The process of the present invention, compared to prior art processes, can be carried out at a high ratio between metallic solid residues, such as spent batteries, and the liquid of the leach solution in the reaction mixture, while maintaining high recovery yields and high selectivities.

[0014] Furthermore, the process is versatile because it can use a wide range of metal residues, particularly spent battery residues, as starting materials. In particular, the process of the present invention allows for the efficient and selective recovery of cobalt, nickel, and manganese from metal residues (i.e., spent battery residues) that have not been subjected to complex pyrometallurgical pretreatments as disclosed in the prior art.

[0015] The inventors have also found that the process involves the use of a simple separation step such as a filtration step under mild conditions, or even the use of a non-organic solvent for the recovery of cobalt, nickel and manganese from the solid cake, allowing the filtrate obtained from the process, which is low in cobalt, nickel and manganese, to be reused as the leach solution.

[0016] Furthermore, the process of the present invention is also advantageous because it is carried out in the absence of harmful reagents and under mild reactions, which means it is environmentally friendly and ensures the safety and health of employees, which is also advantageous because it is easier for its industrial scale-up.

[0017] An embodiment of the present invention is a process for recovering one or more metal ions selected from the group consisting of cobalt, nickel, manganese, and mixtures thereof from a metal-containing residue, the process comprising the steps of: A) leaching the residue with a leach solution containing lactic acid to obtain a leach mixture formed by filtrate 1 containing cobalt lactate, nickel lactate, manganese lactate, or mixtures thereof and solid cake 1; B) separating filtrate 1 from the leach mixture obtained in step A); C) precipitating cobalt lactate, nickel lactate, manganese lactate, or mixtures thereof from filtrate 1 obtained in step B) to obtain a precipitate mixture formed by filtrate 2 and precipitate 1 containing cobalt lactate, nickel lactate, manganese lactate, or mixtures thereof; and D) separating cobalt lactate, nickel lactate, manganese lactate, or mixtures thereof from the precipitation mixture obtained in step C). or alternatively, the process comprises the steps of: A) leaching the residue with a leach solution containing lactic acid to obtain a leach mixture formed by a filtrate 1 containing cobalt lactate, nickel lactate, manganese lactate, or a mixture thereof and a solid cake 1; E) precipitating cobalt lactate, nickel lactate, manganese lactate, or a mixture thereof from the filtrate 1 obtained in step A) to obtain a precipitate mixture formed by a filtrate 3 and a solid cake 2 containing cobalt lactate, nickel lactate, manganese lactate, or a mixture thereof; F) separating the solid cake 2 from the precipitation mixture obtained in step E); and G) separating the cobalt lactate, nickel lactate, manganese lactate, or a mixture thereof from the solid cake 2. [Brief explanation of the drawings]

[0018] [Figure 1] 1 shows a flow chart of a first alternative process for recovering cobalt, nickel and manganese ions from metal-containing residues of the present invention. [Figure 2] 1 shows a flow chart of a second alternative process for recovering cobalt, nickel and manganese ions from metal-containing residues of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0019] All terms used herein in this application shall be understood in their ordinary meaning as known in the art unless otherwise specified. Other, more specific definitions of certain terms used in this application are set forth below and are intended to be applied uniformly throughout the specification and claims, unless a definition expressly set forth otherwise provides a broader definition.

[0020] For purposes of the present invention, any range given includes both the lower and upper endpoints of the range. Given ranges and values ​​for temperature, time, etc. should be considered approximations unless otherwise specified.

[0021] The terms "weight percent (%)," "weight / weight %," and "w / w%" have the same meaning and are used interchangeably. They refer to the weight of a component relative to the total weight of the mixture / composition. For example, the amount of lactic acid in the leaching solution is 40 wt. % relative to the total weight of the leaching solution.

[0022] The term "weight ratio" refers to the relationship of the weight of a given compound to another given compound, for example, the relationship between the weight of a solid and the weight of the liquid phase of a leaching solution.

[0023] As noted above, the process of the present invention for recovering one or more metal ions selected from the group consisting of cobalt, nickel, manganese, and mixtures thereof from a metal-containing residue comprises: A) leaching the residue with a leaching solution containing lactic acid to obtain a leaching mixture formed by a filtrate 1 containing cobalt lactate, nickel lactate, manganese lactate or a mixture thereof and a solid cake 1; B) Separating filtrate 1 from the leaching mixture obtained in step A); C) precipitating cobalt lactate, nickel lactate, manganese lactate or a mixture thereof from the filtrate 1 obtained in step B) to obtain a precipitate mixture formed by the filtrate 2 and the precipitate 1 containing cobalt lactate, nickel lactate, manganese lactate or a mixture thereof; D) separating a precipitate 1 comprising cobalt lactate, nickel lactate, manganese lactate or a mixture thereof from the precipitate mixture obtained in step C); Includes.

[0024] Alternatively, the process of the present invention for recovering one or more metal ions selected from the group consisting of cobalt, nickel, manganese and mixtures thereof from a metal-containing residue comprises: A) leaching the residue with a leaching solution containing lactic acid to obtain a leaching mixture formed by a filtrate 1 containing cobalt lactate, nickel lactate, manganese lactate or a mixture thereof and a solid cake 1; E) precipitating cobalt lactate, nickel lactate, manganese lactate or a mixture thereof from the filtrate 1 obtained in step A) to obtain a precipitation mixture formed by a filtrate 3 and a solid cake 2 containing cobalt lactate, nickel lactate, manganese lactate or a mixture thereof; F) Separating the solid cake 2 from the precipitation mixture obtained in step E); G) Separating cobalt lactate, nickel lactate, manganese lactate or a mixture thereof from the solid cake 2; Includes.

[0025] For purposes of the present invention, the terms "residue," "metal residue," and "metal-containing residue" have the same meaning and are used interchangeably. They refer to residues containing one or more metals or metal oxides. In one embodiment, the process of the present invention for recovering one or more metal ions selected from the group consisting of cobalt, nickel, manganese, and mixtures thereof from a metal-containing residue is a process in which the metal residue is selected from the group consisting of spent batteries, metal alloys, and metal catalysts.

[0026] In one embodiment, the process of the present invention for recovering one or more metal ions selected from the group consisting of cobalt, nickel, manganese, and mixtures thereof from a metal-containing residue is a process in which the residue is a spent battery. In one embodiment, the process of the present invention for recovering one or more metal ions selected from the group consisting of cobalt, nickel, manganese, and mixtures thereof from a metal-containing residue is a process in which the residue is a metal alloy. In one embodiment, the process of the present invention for recovering one or more metal ions selected from the group consisting of cobalt, nickel, manganese, and mixtures thereof from a metal-containing residue is a process in which the residue is a metal catalyst. For purposes of the present invention, all aspects and embodiments disclosed herein (alone or in combination with other embodiments disclosed above or below) form part of the present invention, even if any one of the residue types is taken separately.

[0027] In one embodiment, the process of the present invention for recovering one or more metal ions selected from the group consisting of cobalt, nickel, manganese, and mixtures thereof from a metal-containing residue is a process wherein the metal residue is selected from a cobalt-containing residue, a nickel-containing residue, a manganese-containing residue, a cobalt and nickel-containing residue, a cobalt and manganese-containing residue, a nickel and manganese-containing residue, and a cobalt, nickel and manganese-containing residue. In one embodiment, the process of the present invention for recovering one or more metal ions selected from the group consisting of cobalt, nickel, manganese, and mixtures thereof from a metal-containing residue is a process wherein the metal residue is selected from a cobalt, nickel, and manganese-containing residue. from It is a process of choice.

[0028] In one embodiment, the process of the present invention is a process for recovering cobalt. In one embodiment, the process of the present invention is a process for recovering nickel. In one embodiment, the process of the present invention is a process for recovering manganese. In one embodiment, the process of the present invention is a process for recovering cobalt and nickel. In one embodiment, the process of the present invention is a process for recovering cobalt and manganese. In one embodiment, the process of the present invention is a process for recovering nickel and manganese. In one embodiment, the process of the present invention is a process for recovering cobalt, nickel, and manganese.

[0029] The metal content of the residue determines the metals recovered. For example, if the metal residue contains cobalt and nickel, the process of the present invention is a process for recovering cobalt ions, nickel ions, and mixtures thereof.

[0030] As disclosed above, step A) of the process of the present invention comprises leaching metal residues, in particular spent batteries, with a leaching solution comprising lactic acid to obtain a leaching mixture formed by a filtrate 1 comprising cobalt lactate, nickel lactate, manganese lactate or mixtures thereof, and a solid cake 1 comprising unreacted metal residues, in particular spent battery residues.

[0031] As disclosed above, in one embodiment, the metal residue is a used battery. For the purposes of the present invention, the terms "used battery" and "battery" have the same meaning and are used interchangeably. They refer to primary batteries used as a power source for electronic devices or equipment. Examples of electronic devices or equipment include small portable electronic devices (PEDs), such as mobile phones and laptops; medical equipment; or electric vehicles (EVs).

[0032] Spent batteries can be in several forms. They are generally discharged by immersion in a salt solution, mechanically disassembled, and optionally subjected to additional processing, such as heat treatment. In one embodiment, the spent batteries are discharged and subjected to at least a mechanical disassembly process. Typically, the mechanical disassembly process includes a dismantling and crushing step followed by a screening step that allows the removal of the casing (steel) and part of the current collectors, reducing the cost of the process.

[0033] For the purposes of the present invention, the spent batteries used as starting material are spent batteries containing cobalt, nickel, manganese or mixtures thereof, or a mixture of spent batteries containing cobalt, nickel, manganese or mixtures thereof and spent batteries that do not contain cobalt, nickel, or manganese.

[0034] In one embodiment, the spent battery is a spent battery containing cobalt, nickel, manganese or mixtures thereof selected from the group consisting of lithium ion batteries and nickel-metal hydride batteries, in particular a spent battery that has been discharged and subjected to at least a mechanical disassembly process.

[0035] In one embodiment, the residue is Black Mass In the field of batteries, " Black Mass The term "black mass" refers to a powder containing electrode materials including electrode active material, polymer binder, residual aluminum and copper current collecting materials, and other residual particulates. Black Mass The chemical composition of the scrap electrochemical cell will depend on the chemistry of the scrap electrochemical cell, but for the purposes of this invention, regardless of the origin of the battery, Black Mass contains at least cobalt, nickel, manganese or a mixture thereof. Black MassThe materials forming part of the present invention are selected from the group consisting of materials such as lithium metal oxide, lithium iron phosphate (cathode), graphite (anode), and alkyl carbonates (e.g., C1-C6 alkyl carbonates such as ethylene carbonate (EC), ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), diethyl carbonate (DEC), propylene carbonate (PC), and mixtures thereof), iron, aluminum, copper, plastic, graphite, cobalt, nickel, aluminum, manganese, and of course lithium. Black Mass is generally obtained by mechanical or thermomechanical processes.

[0036] As disclosed above, in one embodiment, the metal residue is a metal alloy. For purposes of the present invention, the terms "metal alloy" and "alloy" have the same meaning and are used interchangeably. They encompass both solid solutions and liquid mixtures of one or more metals with a second material, which may be a metal, a nonmetal, or another alloy. The term solid solution refers to a single-phase solution in which all metal particles (crystals) have the same composition. On the other hand, a liquid mixture of metals refers to two or more solutions that form different crystalline microstructures within the metal.

[0037] Cobalt-nickel-based alloys have excellent performance due to their thermal stability, corrosion resistance, and wear resistance. Historically, they have been used for a wide variety of purposes, including blades for gas turbines and aircraft jet engines, cutting tools for machining, mining and foundation drilling, sports applications, surgical instruments, orthopedic implants, and jewelry. Cobalt and nickel form hard metal blends with chromium or tungsten carbide. In these mixtures, cobalt and nickel wet the other metal particles, forming cemented carbides. Apart from hard metal alloys, cobalt is also used as an alloy with samarium for the production of permanent magnets.

[0038] As disclosed above, in one embodiment, the metal residue is a "metal catalyst." The term "metal catalyst" refers to a catalyst composed primarily or exclusively of one or more metals, or more commonly one or more metal oxides. A metal catalyst may consist solely of one or more metals, one or more metal oxides, or a mixture thereof, or may include a metal, metal oxide, or a mixture thereof dispersed on a support such as alumina. The term "catalyst" refers to a substance that increases the rate of a chemical reaction.

[0039] Cobalt catalysts are highly active reagents and are widely applied in the efficient and selective synthesis of new chemical products and in oil desulfurization processes. Cobalt's redox properties allow for different valence states and facilitate the easy transfer of electrons between these states, speeding up reactions.

[0040] As mentioned above, step A) involves leaching the metal residue, in particular spent batteries. The term "leaching" refers to the process of separating valuable metals, such as cobalt, nickel, and manganese, from one of the less valuable components of the residue, and refers to an extraction step. For the purposes of the present invention, the extraction step is carried out by mixing the metal residue, in particular spent batteries, with a leaching solution containing lactic acid under such reaction conditions to obtain a leaching mixture formed by a filtrate 1 containing cobalt lactate, nickel lactate, manganese lactate, or a mixture thereof, and a solid cake 1 formed by the remaining unreacted, less valuable components of the batteries.

[0041] In one embodiment, in step A), the leaching solution further comprises one or more organic acids, one or more reducing agents, one or more proton acceptors, one or more solvents and mixtures thereof.

[0042] In one embodiment, in step A), the leaching solution further comprises one or more organic acids selected from the group consisting of citric acid, acetic acid, formic acid, malonic acid, maleic acid, succinic acid and tartaric acid. In one embodiment, in step A), the leaching solution further comprises one or more organic acids as defined above, in particular citric acid, in an amount of 2 to 11 wt. % relative to the total weight of the leaching solution. In one embodiment, in step A), the leaching solution further comprises one or more organic acids as defined above, in particular citric acid, in an amount of 3 to 9 wt. % relative to the total weight of the leaching solution.

[0043] In one embodiment, in step A), the leaching solution further comprises one or more reducing agents. The term "reducing agent" refers to any compound that reduces another compound, thereby bringing the reducing agent to an oxidized state by losing the electrons donated during the reduction. In one embodiment, in step A), the leaching solution further comprises one or more reducing agents selected from the group consisting of non-precious metals, organic reducing agents, hydrogen peroxide, and mixtures thereof. In one embodiment, in step A), the leaching solution further comprises one or more non-precious metal reducing agents selected from the group consisting of Cu, Al, and mixtures thereof. In one embodiment, in step A), the leaching solution further comprises one or more organic reducing agents selected from the group consisting of ascorbic acid, formic acid, oxalic acid, and mixtures thereof. In one embodiment, the leaching solution is leached from residues such as used batteries (especially Black Mass The weight ratio of the amount of cobalt, nickel and manganese in the catalyst to the amount of reducing agent is less than 1.8.

[0044] In one embodiment, in step A), the leaching solution further comprises one or more proton acceptors. The term "proton acceptor" refers to any compound capable of abstracting a proton. In one embodiment, in step A), the leaching solution further comprises one or more proton acceptors selected from the group consisting of quaternary ammonium-containing compounds, quaternary phosphonium-containing compounds, amino acids, sugars, and mixtures thereof. In one embodiment, in step A), the leaching solution further comprises one or more proton acceptors that are one or more ammonium quaternary-containing compounds. In one embodiment, in step A), the leaching solution further comprises one or more proton acceptors selected from the group consisting of choline chloride, tetrabutylammonium chloride, methyltriphenylphosphonium bromide, betaine, alanine, glycine, proline, glucose, and mixtures thereof.

[0045] In one embodiment, in step A), the leaching solution further comprises one or more proton acceptors as defined above, in particular one or more ammonium quaternary-containing compounds, more particularly choline chloride, in an amount of 5-30% based on the total weight of the leaching solution.In one embodiment, in step A), the leaching solution further comprises one or more proton acceptors as defined above, in particular one or more ammonium quaternary-containing compounds, more particularly choline chloride, in an amount of 8-24% based on the total weight of the leaching solution.

[0046] In one embodiment, in step A), the leaching solution further comprises one or more solvents selected from the group consisting of water and mixtures of water with one or more water-miscible organic solvents. In step A), the leaching solution further comprises one or more solvents, in particular water, in an amount of 10% or less relative to the total weight of the leaching solution.

[0047] In one embodiment, in step A), the leaching solution further comprises a mixture of water and one or more water-miscible organic solvents. The term "miscible organic solvent" refers to organic solvents that form a single phase when combined, meaning that the resulting mixture is "single-phase" under certain conditions, particularly component concentrations and temperature. Furthermore, the term "water-miscible organic solvent" refers to an organic solvent that can form a single-phase solution with water at the temperature at which the mixture or reaction is carried out. As used herein, the term "single-phase" also refers to mixtures or reaction media that contain only one liquid phase, and methods using such mixtures or reaction media. In one embodiment, in step A), the leaching solution further comprises a mixture of water and one or more water-miscible organic solvents selected from the group consisting of (C1-C6)alcohols, glycols, (C1-C4)alkyl-CO—(C1-C4)alkyls, (C1-C4)alkyl-CO—O—(C1-C4)alkyls, cyclo(C5-C6)alkanes, phenyl-(C1-C4)alkyls and halogen-(C1-C4)alkanes.

[0048] The term "glycol" refers to a straight- or branched-chain alkane having at least two hydroxyl substituents. Generally, glycols contain 2 to 12 carbon atoms (i.e., (C2-C6) 12) glycol). For purposes of the present invention, the term "glycol" also encompasses polymeric forms of the glycols described herein. For example, the designation "C2 glycol" is intended to include both ethylene glycol and polyethylene glycol. Non-limiting examples of glycols include, but are not limited to, methylene glycol, ethylene glycol, propylene glycol, butylene glycol, polyethylene glycol (PEG), and hexylene glycol. Glycol compounds may contain chiral centers and therefore may exist in different enantiomeric and diastereomeric forms. Additionally, different positional isomers of glycol compounds may exist. Any positional isomers, any optical isomers, and any stereoisomers of these compounds and mixtures thereof are also encompassed by the term "glycol" and can be used in the present invention. In one embodiment, the water-miscible organic solvent is one or more glycols, particularly polyethylene glycol (PEG).

[0049] The term "alcohol" refers to an "alkane" having at least one hydrogen atom replaced with a hydroxyl group and containing the number of carbon atoms specified in the specification or claims. The term "alkane" refers to a saturated, branched, or straight-chain hydrocarbon containing the number of carbon atoms specified in the specification or claims. Examples include methanol, ethanol, n-propanol, isopropanol, butanol, isobutanol, and sec-butanol. The term "alkyl" is as defined above. In one embodiment, step (a) is performed in the presence of ethyl acetate. The term "cycloalkane" refers to a "cyclic" alkane containing the number of carbon atoms specified in the specification or claims. The term cycloalkane includes carbocyclic alkanes or heterocyclic alkanes. The term "carbocyclic" alkanes refer to cyclic alkanes in which each atom of the ring is a carbon atom. Examples of carbocyclic alkanes include cyclopentane and cyclohexane. The term "heterocyclic" alkanes refer to "carbocyclic" compounds in which at least one carbon atom is replaced with an N, NH, O, or S atom. Examples of heterocyclic alkanes include tetrahydrofuran and tetrahydropyran. The term "halogen-alkane" refers to an alkane in which at least one hydrogen atom has been replaced with a halogen atom and which contains a number of carbon atoms specified in the specification or claims. Examples of halogen-alkanes include chloroform, trichloroethane, dichloroethane, etc. In one embodiment, in step A), the leaching solution further comprises a mixture of water and one or more water-miscible organic solvents selected from the group consisting of acetone, ethyl acetate, water, cyclohexane, chloroform, tetrahydrofuran, toluene, dichloromethane, and mixtures thereof.

[0050] In step A), if the leaching solution further comprises a mixture of water and one or more water-miscible organic solvents, the amount of the one or more water-miscible organic solvents is not more than 10% by weight of the weight of the water mixture.

[0051] In one embodiment, in step A), the leaching solution further comprises water as a solvent.

[0052] In one embodiment, in step A), the leaching solution comprises lactic acid and one or more solvents, in particular water. In one embodiment, in step A), the leaching solution consists of lactic acid and one or more solvents, in particular water. In one embodiment, in step A), the leaching solution consists of lactic acid and water.

[0053] In one embodiment, in step A), the leaching solution comprises lactic acid, one or more organic acids, one or more proton acceptors, and one or more solvents. In one embodiment, in step A), the leaching solution comprises lactic acid, citric acid, choline chloride, and water. In one embodiment, in step A), the leaching solution consists of lactic acid, one or more organic acids, one or more proton acceptors, and one or more solvents. In one embodiment, in step A), the leaching solution consists of lactic acid, citric acid, choline chloride, and water.

[0054] In one embodiment, in step A), the amount of lactic acid in the leaching solution defined in the present invention is 10% to 80% by weight of lactic acid relative to the total weight of the leaching solution. In one embodiment, in step A), the leaching solution comprises lactic acid and one or more solvents (particularly water), and the amount of lactic acid is 10% to 40% by weight of lactic acid relative to the total weight of the leaching solution. In one embodiment, in step A), the leaching solution comprises lactic acid and one or more solvents (particularly water), and the amount of lactic acid is 11% to 38% by weight of lactic acid relative to the total weight of the leaching solution. In one embodiment, in step A), the leaching solution comprises lactic acid and one or more solvents (particularly water), and the amount of lactic acid is 25% to 38% by weight of lactic acid relative to the total weight of the leaching solution. In one embodiment, in step A), the leaching solution comprises lactic acid and one or more solvents (especially water), the amount of lactic acid being 30% to 38% by weight of lactic acid relative to the total weight of the leaching solution. In one embodiment, in step A), the leaching solution comprises lactic acid and one or more solvents (especially water), the amount of lactic acid being about 36% by weight of lactic acid relative to the total weight of the leaching solution.

[0055] In one embodiment, in step A), the leaching solution comprises lactic acid and one or more solvents (especially water), wherein the amount of lactic acid is 10% to 80% by weight of lactic acid relative to the total weight of the leaching solution. In one embodiment, in step A), the leaching solution comprises lactic acid and one or more solvents (especially water), wherein the amount of lactic acid is 10% to 40% by weight of lactic acid relative to the total weight of the leaching solution. In one embodiment, in step A), the leaching solution comprises lactic acid and one or more solvents (especially water), wherein the amount of lactic acid is 11% to 38% by weight of lactic acid relative to the total weight of the leaching solution. In one embodiment, in step A), the leaching solution comprises lactic acid and one or more solvents (especially water), wherein the amount of lactic acid is 25% to 38% by weight of lactic acid relative to the total weight of the leaching solution. In one embodiment, in step A), the leaching solution consists of lactic acid and one or more solvents (particularly water), with the amount of lactic acid being 30% to 38% by weight of lactic acid relative to the total weight of the leaching solution. In one embodiment, in step A), the leaching solution consists of lactic acid and one or more solvents (particularly water), with the amount of lactic acid being about 36% by weight of lactic acid relative to the total weight of the leaching solution. In a particular embodiment, the leaching solution of step A) consists of about 36% lactic acid and about 64% water.

[0056] As used herein, the term "about" or "around" refers to a range of ±10% of a particular value. For example, the expression "about 36" or "approximately 36" includes ±10% of 10, i.e., 32.4 to 39.6.

[0057] In one embodiment, in step A), the leaching solution further comprises one or more organic acids, one or more reducing agents, one or more proton acceptors, one or more solvents and mixtures thereof, wherein the amount of lactic acid is 10% to 40% by weight, particularly 11% to 38% by weight, more particularly 11% to 31% by weight, relative to the total weight of the leaching solution. In one embodiment, in step A), the leaching solution further comprises lactic acid, one or more organic acids, one or more proton acceptors and one or more solvents as defined above, wherein the amount of lactic acid is 10% to 40% by weight, particularly 11% to 38% by weight, more particularly 11% to 31% by weight, relative to the total weight of the leaching solution. In one embodiment, in step A), the leaching solution comprises lactic acid, citric acid, choline chloride and water, wherein the amount of lactic acid is 10% to 40% by weight, in particular 11% to 38% by weight, more particularly 11% to 31% by weight, of lactic acid relative to the total weight of the leaching solution.

[0058] In one embodiment, in step A), the leaching solution consists of lactic acid, one or more organic acids, one or more proton acceptors and one or more solvents, and the amount of lactic acid is between 10% and 40% by weight, in particular between 11% and 38% by weight, more particularly between 11% and 31% by weight, of lactic acid relative to the total weight of the leaching solution.

[0059] In one embodiment, in step A), the leaching solution consists of lactic acid, citric acid, choline chloride and water, and the amount of lactic acid is 10% to 40% by weight, in particular 11% to 38% by weight, more particularly 11% to 31% by weight, of lactic acid relative to the total weight of the leaching solution.

[0060] In one embodiment, in step A), the leaching solution comprises: 10 to 40% by weight of lactic acid based on the total weight of the leaching solution; 5-30% by weight of one or more proton acceptors, particularly ammonium quaternary-containing compounds, especially choline chloride, based on the total weight of the leaching solution; 2 to 11% by weight of one or more organic acids, in particular citric acid, relative to the total weight of the leaching solution; Sufficient water to make up to 100% by weight; Includes.

[0061] In one embodiment, in step A), the leaching solution comprises: 11 to 38% by weight of lactic acid based on the total weight of the leaching solution; 8-24% by weight of one or more proton acceptors, particularly ammonium quaternary-containing compounds, especially choline chloride, based on the total weight of the leaching solution; 3 to 9% by weight of one or more organic acids, in particular citric acid, relative to the total weight of the leaching solution; Sufficient water to make up to 100% by weight; Includes.

[0062] In one embodiment, in step A), the leaching solution comprises: 11 to 31% by weight of lactic acid based on the total weight of the leaching solution; 8-24% by weight of one or more proton acceptors, particularly ammonium quaternary-containing compounds, especially choline chloride, based on the total weight of the leaching solution; 3 to 9% by weight of one or more organic acids, in particular citric acid, relative to the total weight of the leaching solution; Sufficient water to make up to 100% by weight; Includes.

[0063] In one embodiment, in step A), the leaching solution comprises: 10 to 40% by weight of lactic acid based on the total weight of the leaching solution; 5-30% by weight of one or more proton acceptors, particularly ammonium quaternary-containing compounds, especially choline chloride, based on the total weight of the leaching solution; 2 to 11% by weight of one or more organic acids, in particular citric acid, relative to the total weight of the leaching solution; Sufficient water to make up to 100% by weight; It consists of:

[0064] In one embodiment, in step A), the leaching solution comprises: 11 to 38% by weight of lactic acid based on the total weight of the leaching solution; 8-24% by weight of one or more proton acceptors, particularly ammonium quaternary-containing compounds, especially choline chloride, based on the total weight of the leaching solution; 3 to 9% by weight of one or more organic acids, in particular citric acid, relative to the total weight of the leaching solution; Sufficient water to make up to 100% by weight; It consists of:

[0065] In one embodiment, in step A), the leaching solution comprises: 11 to 31% by weight of lactic acid based on the total weight of the leaching solution; 8-24% by weight of one or more proton acceptors, particularly ammonium quaternary-containing compounds, especially choline chloride, based on the total weight of the leaching solution; 3 to 9% by weight of one or more organic acids, in particular citric acid, relative to the total weight of the leaching solution; Sufficient water to make up to 100% by weight; It consists of:

[0066] In one embodiment, in step A), the leaching solution comprises: 31% by weight of lactic acid relative to the total weight of the leaching solution; 24% by weight of one or more proton acceptors, particularly ammonium quaternary-containing compounds, especially choline chloride, based on the total weight of the leaching solution; 9% by weight of one or more organic acids, in particular citric acid, relative to the total weight of the leaching solution; Sufficient water to make up to 100% by weight; Includes.

[0067] In one embodiment, in step A), the leaching solution comprises: 31% by weight of lactic acid relative to the total weight of the leaching solution; 24% by weight of one or more proton acceptors, particularly ammonium quaternary-containing compounds, especially choline chloride, based on the total weight of the leaching solution; 9% by weight of one or more organic acids, in particular citric acid, relative to the total weight of the leaching solution; 36% water, It consists of:

[0068] In one embodiment, in step A), the leaching solution comprises: 20% by weight of lactic acid relative to the total weight of the leaching solution; 15% by weight of one or more proton acceptors, particularly ammonium quaternary-containing compounds, especially choline chloride, based on the total weight of the leaching solution; 6% by weight of one or more organic acids, in particular citric acid, relative to the total weight of the leaching solution; Sufficient water to make up to 100% by weight; Includes.

[0069] In one embodiment, in step A), the leaching solution comprises: 20% by weight of lactic acid relative to the total weight of the leaching solution; 15% by weight of one or more proton acceptors, particularly ammonium quaternary-containing compounds, especially choline chloride, based on the total weight of the leaching solution; 6% by weight of one or more organic acids, in particular citric acid, relative to the total weight of the leaching solution; 59% water, It consists of:

[0070] In one embodiment, in step A), the leaching solution comprises: 31% by weight of lactic acid relative to the total weight of the leaching solution; 24% by weight of one or more proton acceptors, particularly ammonium quaternary-containing compounds, especially choline chloride, based on the total weight of the leaching solution; 9% by weight of one or more organic acids, in particular citric acid, relative to the total weight of the leaching solution; 36% water, It consists of:

[0071] In one embodiment, in step A), the leaching solution comprises: 11% by weight of lactic acid relative to the total weight of the leaching solution; 8% by weight of one or more proton acceptors, particularly ammonium quaternary-containing compounds, especially choline chloride, based on the total weight of the leaching solution; 3% by weight of one or more organic acids, in particular citric acid, relative to the total weight of the leaching solution; Sufficient water to make up to 100% by weight; Includes.

[0072] In one embodiment, in step A), the leaching solution comprises: 11% by weight of lactic acid relative to the total weight of the leaching solution; 8% by weight of one or more proton acceptors, particularly ammonium quaternary-containing compounds, especially choline chloride, based on the total weight of the leaching solution; 3% by weight of one or more organic acids, in particular citric acid, relative to the total weight of the leaching solution; 78% water, It consists of:

[0073] In one embodiment, step A) is carried out at a temperature of 20°C to 100°C. In one embodiment, step A) is carried out at a temperature of 50°C to 100°C. In one embodiment, step A) is carried out at a temperature of 55°C to 85°C.

[0074] In one embodiment, step A) is carried out for 20 minutes to 24 hours. In one embodiment, step A) is carried out for 30 minutes to 10 hours. In one embodiment, step A) is carried out for 30 minutes to 4 hours.

[0075] In one embodiment, step A) further comprises adding one or more additives to the resulting leaching mixture. In one embodiment, step A) further comprises adding one or more additives to the resulting leaching mixture selected from the group consisting of reducing agents and oxidizing agents.

[0076] In embodiments where the metal residue, particularly spent batteries, used as starting material for the process of the present invention is obtained by mechanical procedures and / or by heat treatment at low temperatures (i.e., below 500°C), the process further comprises adding one or more reducing agents to the resulting leaching mixture. The reducing agent may be any one of those defined above in the present invention. All embodiments disclosed above for the reducing agent in the leaching mixture also apply to the reducing agent additionally added to the leaching mixture. Suitable reducing agents and their amounts can be easily determined by those skilled in the art according to the type of metal residue, particularly spent batteries, used as starting material and their metal composition.

[0077] In embodiments where the metal residue, particularly spent batteries, used as starting material for the process of the present invention is obtained by heat treatment at high temperatures (i.e., above 500°C), the process further comprises adding one or more oxidizing agents to the obtained leaching mixture. The term "oxidizing agent" refers to any compound that oxidizes other materials, thereby bringing the oxidizing agent to a reduced state by accepting electrons removed by oxidation. In one embodiment, the oxidizing agent is selected from the group consisting of peroxides, ozone, alkali or alkaline earth chlorites, and mixtures thereof. In one embodiment, the oxidizing agent is hydrogen peroxide. Suitable oxidizing agents and their amounts can be easily determined by those skilled in the art according to the type of metal residue, particularly spent batteries, used as starting material and their metal composition. In one embodiment, the amount of oxidizing agent and the amount of oxidizing agent in the leaching mixture (particularly spent batteries) can be easily determined according to the type of metal residue, particularly spent batteries, used as starting material and their metal composition. Black Mass The weight ratio between the amounts of cobalt, nickel and manganese in the metal residues of used batteries and the like is higher than 2.8.

[0078] In one embodiment, step A) comprises leaching the metal residue, in particular spent batteries, with a leaching solution comprising lactic acid to obtain a leaching mixture, maintaining the leaching mixture under conditions defined herein for 20 and 40 minutes, in particular for 30 minutes, and subsequently adding one or more additives as defined above to the leaching mixture. In one embodiment, step A) comprises leaching the metal residue, in particular spent batteries, with a leaching solution comprising lactic acid to obtain a leaching mixture, maintaining the leaching mixture under conditions defined herein for 20 and 40 minutes, in particular for 30 minutes, subsequently adding one or more additives as defined above to the leaching mixture, and maintaining the resulting leaching mixture for the remaining time, up to 24 hours.

[0079] In one embodiment, in step A), the weight relationship between the metal residue containing cobalt, nickel, and manganese, particularly used batteries, and the leaching solution is 1:5 to 1:70. In one embodiment, in step A), the weight relationship between the metal residue containing cobalt, nickel, and manganese, particularly used batteries, and the leaching solution is 1:9 to 1:70. In one embodiment, in step A), the weight relationship between the metal residue containing cobalt, nickel, and manganese, particularly used batteries, and the leaching solution is 1:9 to 1:58. In one embodiment, in step A), the weight relationship between the metal residue containing cobalt, nickel, and manganese, particularly used batteries, and the leaching solution is 1:9 to 1:58.

[0080] As mentioned above, the first alternative process of the invention comprises carrying out a step C) of precipitating cobalt lactate, nickel lactate, manganese lactate or mixtures thereof from the filtrate 1 obtained in step B) to obtain a precipitate mixture formed by the filtrate 2 and a precipitate 1 comprising cobalt lactate, nickel lactate, manganese lactate or mixtures thereof. Step C) implies the precipitation of cobalt lactate, nickel lactate, manganese lactate or mixtures thereof and thus their selective and effective separation from the remaining unreacted and metallic components present in the filtrate 1.

[0081] In one embodiment, step C) of the process of the present invention is carried out at a temperature between 20°C and 100°C. In one embodiment, step C) is carried out at a temperature between 20°C and 50°C. In one embodiment, step C) is carried out at a temperature between 50°C and 100°C. In one embodiment, step C) is carried out at a temperature between 55°C and 85°C.

[0082] In one embodiment, step C) of the process of the present invention is carried out for a period of time suitable to obtain a precipitate. In one embodiment, step C) of the process of the present invention is carried out for a period of 20 minutes to 7 days. In one embodiment, step C) of the process of the present invention is carried out for a period of 20 minutes to 72 hours. In one embodiment, step B) of the process of the present invention is carried out for a period of 30 minutes to 48 hours. In one embodiment, step B) of the process of the present invention is carried out for a period of 30 minutes to 8 hours.

[0083] In one embodiment, step C) of the process of the present invention is carried out at a temperature of 20°C to 50°C for a suitable period of time to obtain a precipitate. In one embodiment, step C) of the process of the present invention is carried out at a temperature of 20°C to 50°C for a period of 20 minutes to 7 days. In one embodiment, step C) of the process of the present invention is carried out at a temperature of 20°C to 50°C for a period of 20 minutes to 72 hours. In one embodiment, step B) of the process of the present invention is carried out at a temperature of 20°C to 50°C for a period of 30 minutes to 48 hours. In one embodiment, step B) of the process of the present invention is carried out at a temperature of 20°C to 50°C for a period of 30 minutes to 8 hours. In one embodiment, the precipitation yield of cobalt lactate in step B) is 50% by weight or more. In one embodiment, the precipitation yield of nickel lactate in step B) is 48% by weight or more. In one embodiment, the precipitation yield of manganese lactate in step B) is 32% by weight or more.

[0084] As described above, the second alternative process of the present invention includes carrying out step E) of precipitating cobalt lactate, nickel lactate, manganese lactate, or a mixture thereof from filtrate 1 to obtain a precipitation mixture formed by filtrate 3 and solid cake 2 containing cobalt lactate, nickel lactate, manganese lactate, or a mixture thereof and an unreacted (battery) residue sample. Thus, step E) means that cobalt lactate, nickel lactate, manganese lactate, or a mixture thereof is precipitated directly from the leaching mixture without prior separation of the unreacted (battery) residue sample. Thus, solid cake 2 thus obtained is formed by a mixture of cobalt lactate, nickel lactate, manganese lactate, or a mixture thereof with the unreacted (battery) residue sample. Nevertheless, due to the difference in water solubility of cobalt lactate, nickel lactate, manganese lactate, or a mixture thereof compared to the unreacted (battery) residue sample, cobalt lactate, nickel lactate, manganese lactate, or a mixture thereof can be easily separated by the addition of water, as disclosed in step G.

[0085] In one embodiment, step E) of the process of the present invention is carried out at a temperature between 20°C and 100°C. In one embodiment, step E) is carried out at a temperature between 20°C and 50°C. In one embodiment, step E) is carried out at a temperature between 50°C and 100°C. In one embodiment, step E) is carried out at a temperature between 55°C and 85°C.

[0086] In one embodiment, step E) of the process of the present invention is carried out for a period of time suitable to obtain a precipitate. In one embodiment, step E) of the process of the present invention is carried out for a period of time between 20 minutes and 48 hours. In one embodiment, step E) of the process of the present invention is carried out for a period of time between 30 minutes and 24 hours.

[0087] In one embodiment, step E) of the process of the present invention is carried out at a temperature between 20°C and 50°C for a suitable period of time to obtain a precipitate. In one embodiment, step E) of the process of the present invention is carried out at a temperature between 20°C and 50°C for a period of time between 20 minutes and 48 hours. In one embodiment, step E) of the process of the present invention is carried out at a temperature between 20°C and 50°C for a period of time between 30 minutes and 24 hours.

[0088] In an embodiment, the precipitation yield of cobalt lactate in step E) is 79% by weight or greater. In an embodiment, the precipitation yield of nickel lactate in step E) is 71% by weight or greater. In an embodiment, the precipitation yield of manganese lactate in step E) is 45% by weight or greater.

[0089] In one embodiment, each of the separation steps B), D), and F) of the process of the present invention is carried out by a suitable technique known to those skilled in the art for separating solids and liquids, such as by one or more of the following operations: filtration, filtration under vacuum, and decantation. In one embodiment, each of the separation steps B), D), and F) of the process of the present invention is carried out by filtration of the solids.

[0090] In one embodiment, each of the filtration steps defined in B), D) and F) above is carried out at a temperature of 20°C to 100°C. In one embodiment, each of the filtration steps defined in B), D) and F) above is carried out at a temperature of 20°C to 50°C. In one embodiment, each of the filtration steps defined in B), D) and F) above is carried out at a temperature of 50°C to 100°C. In one embodiment, each of the filtration steps defined in B), D) and F) above is carried out at a temperature of 55°C to 85°C.

[0091] In one embodiment, each of precipitation steps C) and E) of the process of the invention is carried out at a pH of 1.5 to 5. In one embodiment, each of precipitation steps C) and E) of the process of the invention includes the addition of a pH adjuster. In one embodiment, each of precipitation steps C) and E) of the process of the invention includes the addition of a pH adjuster in an amount sufficient to have a pH of 1.5 to 5. In one embodiment, each of precipitation steps C) and E) of the process of the invention includes the addition of lactic acid. In one embodiment, each of precipitation steps C) and E) of the process of the invention is carried out by the addition of lactic acid followed by the addition of a pH adjuster. In one embodiment, each of precipitation steps C) and E) of the process of the invention is carried out by the addition of lactic acid followed by the addition of a pH adjuster in an amount sufficient to have a pH of 1.5 to 5. In one embodiment, each of precipitation steps C) and E) of the process of the invention is carried out by the addition of an alkali or alkaline earth metal lactate salt. The term "alkali metal salt" refers to a salt formed with an alkali metal. Alkali metals are a set of elements in Group (I) of the periodic table, including lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr). The term "alkaline earth metal salts" refers to salts formed with alkaline earth metals. Alkaline earth metals are a set of elements in Group II of the periodic table, including beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra).

[0092] In one embodiment, the process further comprises one or more additional drying steps after the filtration step defined above (i.e., after steps B), D), and F). Generally, each drying step comprises subjecting the filtrate and / or solid cake to drying conditions to partially or totally remove the amount of solvent and volatile components of the liquid phase. In one embodiment, the process further comprises partially drying one or more of the filtrates until they have an appropriate amount of solvent and volatile components. In one embodiment, the process further comprises partially or totally drying one or more solids obtained in the process.

[0093] In one embodiment, each drying step is carried out at a temperature of 60° C. to 100° C., particularly 80° C. to 100° C. In one embodiment, each drying step is carried out for 1 to 3 hours, particularly about 2 hours. In one embodiment, each drying step is carried out under vacuum conditions, typically the vacuum comprises a pressure of 0.5 mbar to 3 mbar.

[0094] In one embodiment, separation step G) is carried out by mixing the solid cake 2 obtained in step F) with a solvent selected from water and mixtures of water with one or more miscible organic solvents, leading to a solid cake 3 comprising unreacted (spent battery) residues and a filtrate 4 comprising cobalt lactate, nickel lactate, manganese lactate or mixtures thereof. For the purposes of the present invention, the miscible organic solvents defined above for carrying out step A) of the present process also apply to step F).

[0095] In one embodiment, separation step G) is carried out by mixing the solid cake 2 obtained in step F) with water to result in a solid cake 3 comprising unreacted (spent battery) residues and a filtrate 4 comprising cobalt lactate, nickel lactate, manganese lactate or mixtures thereof.

[0096] In one embodiment, the process further comprises the additional step of isolating cobalt, nickel, and manganese in solid form from the filtrate 4 containing cobalt lactate, nickel lactate, manganese lactate, or a mixture thereof. Generally, the isolation step is carried out by removing the liquid phase as defined above for the drying step, or alternatively by adding an additional precipitating agent to obtain the cobalt, nickel, and manganese in solid form. Examples of additional precipitating agents for isolating the cobalt, nickel, and manganese in solid form include, but are not limited to, organic acids such as oxalic acid, acetic acid, and formic acid.

[0097] The process of the present invention is also advantageous because it allows for the recycling of one or more filtrates obtained during the process, which may contain residues or small amounts of cobalt lactate, nickel lactate, manganese lactate, or mixtures thereof. In one embodiment, the process of the present invention comprises reusing filtrate 2 obtained in step D) of step A) as a leach solution. In one embodiment, the process of the present invention comprises reusing filtrate 3 obtained in step F) of step A) as a leach solution.

[0098] In one embodiment, the reuse of filtrate 2 and / or filtrate 3 includes the addition of one or more additives to adjust the amount of organic compounds and pH.

[0099] Suitable additives may be one or more organic acids, one or more reducing agents, one or more oxidizing agents, one or more proton acceptors, one or more solvents, pH adjusters and mixtures thereof.

[0100] Suitable additives and their amounts can be easily determined by those skilled in the art according to the composition and pH of filtrate 2 and filtrate 3.

[0101] All embodiments disclosed above for the organic acid, reducing agent, oxidizing agent, proton acceptor and solvent as defined above herein also apply to the reconditioning of filtrate 2 and / or 3 as leaching solution in step A).

[0102] The terms "pH adjusting" agent and "pH regulator" agent have the same meaning and are used interchangeably. They refer to an acid or base that can be used to adjust the pH of a finished composition to a desired level without affecting the properties of the composition. The acid(s) and / or base(s) can be added to the composition in any suitable form, such as anhydrous, hydrated, aqueous, or salt form. In one embodiment, the pH adjuster is a base. Examples of suitable bases include alkali metal and alkaline earth metal hydroxides, ammonium hydroxide, substituted ammonium hydroxides (e.g., primary, secondary, tertiary, or quaternary ammonium hydroxides), and mixtures thereof. In one embodiment, the pH adjuster is an acid. Examples of suitable acids include hydrochloric acid, sulfuric acid, and nitric acid. The amount of pH adjuster in the compositions of the present invention is appropriate to achieve a pH of 0.5 to 1.5.

[0103] Reusing filtrate 2 and / or filtrate 3 is particularly advantageous because it can increase the recovery yield of cobalt, nickel, and manganese. In particular, reusing a filtrate (i.e., leaching work solution) that still contains a certain amount of extracted cobalt lactate, nickel lactate, manganese lactate, or a mixture thereof in solution allows for their precipitation in subsequent cycles of the process, thus increasing the amount of extracted and isolated cobalt lactate, nickel lactate, manganese lactate, or a mixture thereof in solid form. In one embodiment, each of the individually obtained filtrates 2 and / or 3 is reused as a leaching solution. In one embodiment, the mixture of filtrate 2, filtrate 3, or a mixture of filtrates 2 and 3 is subjected to leaching before being reused as a leaching solution.

[0104] The recovery of metals other than cobalt, nickel, and manganese from filtrate 2 and / or filtrate 3 is particularly advantageous. In particular, the precipitation of cobalt, nickel, and manganese from filtrate 2 and / or filtrate 3 and / or their reuse as a leaching solution can increase the concentration of other valuable metals, such as copper, aluminum, and especially lithium. Therefore, the recovery of additional metals from filtrate 2 and / or filtrate 3 is also part of the present invention. In one embodiment, the process of the present invention further comprises the additional step of subjecting filtrate 2 obtained in step D), filtrate 3 obtained in step F), a mixture of filtrates 2 obtained in step D), a mixture of filtrates 3 obtained in step F), or a mixture thereof, to such conditions to recover one or more metal ions selected from the group consisting of lithium ions, copper ions, aluminum ions, and mixtures thereof. Appropriate recovery conditions, such as solvents, reagents, and their amounts, can be easily determined by those skilled in the art according to the type of metal ions to be recovered. In one embodiment, the process of the present invention further comprises the additional step of subjecting the filtrate 2 obtained in step D), the filtrate 3 obtained in step F), the mixture of the filtrates 2 obtained in step D), the mixture of the filtrates 3 obtained in step F), or a mixture thereof, to such conditions to recover lithium ions. In one embodiment, the process of the present invention further comprises the additional step of adding an alkali metal or alkaline earth metal carbonate to the filtrate 2 obtained in step D), the filtrate 3 obtained in step F), the mixture of the filtrates 2 obtained in step D), the mixture of the filtrates 3 obtained in step F), or a mixture thereof, to obtain a precipitate of lithium carbonate (W. Gao et al., "Lithium Carbonate Recovery from Cathode Scrap of Spent Lithium-Ion Battery: A Closed-Loop Process," "Environ. Sci. Technol., 2017, vol. 51, no. 3, pp. 1662-1669). The resulting lithium carbonate is then isolated from the reaction medium.

[0105] In one embodiment, the extraction yield of cobalt ions is 80% by weight or greater, in one embodiment, the extraction yield of nickel ions is greater than 73% by weight, and in one embodiment, the extraction yield of manganese ions is greater than 87% by weight.

[0106] As described above, the process of the present invention is an efficient process for recovering cobalt ions, nickel ions, and manganese ions from metal residues such as spent batteries. In one embodiment, the recovery yield of cobalt ions from the metal residue is 50% by weight or more. In one embodiment, the recovery yield of nickel ions from the metal residue is 48% by weight or more. In one embodiment, the recovery yield of manganese ions from the metal residue is 32% by weight or more. In one embodiment, the recovery yield of cobalt ions from the metal residue is 50 to 80% by weight. In one embodiment, the recovery yield of nickel ions from the metal residue is 48% by weight to 75% by weight. In one embodiment, the recovery yield of manganese ions from the metal residue is 32% by weight to 51% by weight.

[0107] In one embodiment, the selectivity of recovery of cobalt, nickel and manganese ions independent of the remaining metals of metal residues such as spent batteries is 75% or greater.

[0108] The process of the present invention allows for the extraction and recovery of cobalt ions, nickel ions, manganese ions, or mixtures thereof from metal-containing residues, such as spent batteries, in the form of cobalt lactate, nickel lactate, manganese lactate, or mixtures thereof. The recovered cobalt lactate, nickel lactate, manganese lactate, or mixtures thereof thus obtained can be used directly, for example, in the fields of inks and pigments, catalysts, and metal plating finishing baths. Alternatively, the recovered cobalt lactate, nickel lactate, manganese lactate, or mixtures thereof can be converted into other cobalt-, nickel-, and / or manganese-containing compounds. In one embodiment, the process of the present invention further comprises an additional step of converting the cobalt lactate, nickel lactate, manganese lactate, or mixtures thereof into mixed oxides containing cobalt, nickel, manganese, or mixtures thereof. Typically, this conversion involves a calcination step. In particular, cobalt lactate, nickel lactate, manganese lactate, or mixtures thereof can be first mixed with external Co, Ni, or Mn compounds (to adjust the new desired metal ratio chemistry) and, among other things, with the necessary lithium, and then the resulting mixture is calcined under appropriate reaction conditions to obtain a mixed oxide. The mixed oxide containing cobalt, nickel, manganese, or a mixture thereof with lithium is used as the active cathode material in the fabrication of new batteries. In one embodiment, the process of the present invention further includes an additional step of converting the cobalt lactate, nickel lactate, manganese lactate, or mixtures thereof to cobalt, nickel, and manganese metal. Typically, this conversion involves an electrodeposition step. In particular, the cobalt lactate, nickel lactate, manganese lactate, or mixtures thereof are plated. Cobalt, nickel, and manganese metals are used in special metal alloys, magnets, electronic devices, and catalysts.

[0109] As mentioned above, the process of the present invention also allows for the recovery of metals other than cobalt, nickel, and manganese, such as copper, aluminum, and lithium, from filtrate 2 and / or filtrate 3. As in the case of cobalt, nickel, and manganese, these additional metals are recovered in the form of metal salts. In particular, in the case of lithium, they can be recovered in the form of lithium carbonate. These metal salts can be used directly, for example, in the fields of inks and pigments, catalysts, and metal plating finishing baths. Alternatively, these metal salts can be converted to other metal-containing compounds, such as metal oxides, following processes similar to those disclosed above for cobalt, nickel, and manganese. Furthermore, these metal salts can also be converted to metals according to processes known in the art. For example, lithium ions present in filtrate 2 and / or filtrate 3 can be recovered in the form of lithium carbonate, which is useful for a wide range of applications, from the pharmaceutical or ceramic industries to the production of new lithium-based batteries.

[0110] In one embodiment, the process of the present invention is selected from the group consisting of a batch process, a semi-continuous process, and a continuous process. In one embodiment, the process of the present invention is selected from the group consisting of a "batch process." The term "batch process" refers to a process consisting of a sequence of one or more steps that must be performed in a defined order. At the end of the sequence, a finite amount of final product is produced. The same series of steps is repeated to produce another finite amount of final product. Thus, starting materials and reagents are added at the beginning or during the reaction process, but are discharged at the end of the process. In one embodiment, the process of the present invention is a "continuous process." The term "continuous process" refers to a process in which the starting materials, reagents, and / or fluids (medium) being processed are in continuous motion and undergo chemical reactions in a continuous process. Thus, starting materials and reagents enter and exit the process throughout the entire process. In one embodiment, the process of the present invention is a "semi-continuous process." The terms "semi-continuous process" and "semi-batch process" have the same meaning and are used interchangeably. They refer to processes that do not fit neatly into any of the above categories. In a semi-continuous process, starting materials and reagents can be charged and discharged from the process simultaneously, but at discrete times. In one embodiment, the process of the present invention is a "continuous process" or alternatively a "semi-continuous process," and the process includes a solid retention system. This is advantageous because it allows for continuous or semi-continuous filtration of the solid cake and / or precipitated solids, thereby reducing the reactor's occupancy time. In one embodiment, the process of the present invention is a "continuous process" or alternatively a "semi-continuous process," and the process includes a decant zone, particularly a horizontal decant zone. The dimensions of the decant zone (i.e., length, diameter, etc.) and decanting conditions (i.e., temperature, time, velocity, flow rate, etc.) can be easily determined by those skilled in the art according to the type of metal residue, particularly the type of used batteries, used as starting material and their metal composition.

[0111] Throughout this specification and claims, the word "comprises" and variations of that word are not intended to exclude other technical features, additives, components, or steps. Furthermore, the term "comprises" encompasses the case of "consisting of." Additional objects, advantages, and features of the present invention will become apparent to those skilled in the art upon examination of the specification or may be learned by practice of the present invention. The following examples and drawings are provided for illustrative purposes and are not intended to limit the invention. Reference signs placed in parentheses in connection with the drawings and in the claims are intended merely to enhance the clarity of the claims and should not be construed as limiting the scope of the claims. The present invention further encompasses all possible combinations of the specific and preferred embodiments described herein. [Example]

[0112] General Considerations

[0113] Equipment and Materials Inductively Coupled Plasma Optical Emission Spectroscopy (ICP) Metal composition analysis was performed using an Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) simultaneous measurement spectrometer, model Vista-MPX, CCD Simultaneous (Varian Ltd, Australia).

[0114] Calibration curves were established using aqueous standards by dilution of 1000 mg / L CertiPUR® (Merck, Germany) multi-element standard samples (Ag, Al, B, Ba, Bi, Ca, Cd, Co, Cr, Cu, Fe, Ga, In, K, Li, Mg, Mn, Na, Ni, Pb, Sr, Tl, Zn).

[0115] For digestion of solid samples or dilution of aqueous samples, 65% ExpertQ® HNO3 and 37% ExpertQ® HCl supplied by Scharlab (Spain) were used.

[0116] The organic compositions were analyzed by HPLC using a Waters 2695 HPLC equipped with a Waters 2414 Refractive Index Detector and an Aminex HPX-87H Column (Bio Rad) with a process temperature of 55 °C, using 0.01 N H2SO4 solution at 0.7 ml / min as the carrier.

[0117] sampling For analysis by ICP, solid input material or solid process discharge product, open digestion of representative aliquots (0.2–1 g) of the different materials was carried out in aqua regia (21 ml HCl and 7 ml HNO3) at 130 °C for 1 h. The digested samples were diluted to 100 ml with deionized water, filtered to remove insoluble particles (i.e., plastic, carbon), and finally evaluated by ICP-OES. -To analyze the liquid streams, a dilution of 0.5 g of each sample was carried out with 1 M HCl (up to 25 ml), after which the samples were evaluated by ICP-OES. For the kinetic evolution during the leaching and precipitation process, an extraction of an aliquot of 5 g of leachate (filtered) was carried out to take a representative sample, from which a 0.5 g sample was taken for ICP analysis.

[0118] 1. Cobalt, nickel and manganese recovery process

[0119] A) Battery

[0120] 1.1. Alternative Example 1

[0121] 1.1.1. General Process

[0122] Leaching step A) The leaching medium was prepared by mixing solid and / or liquid organic compounds with deionized water at an appropriate dilution ratio. The leaching medium thus obtained was placed in a 500 ml jacketed reactor equipped with a heat control and coil condenser to prevent evaporation, and the anchor impeller was rotated at 300 rpm until the desired temperature was reached. The mixture was maintained at the same stirring speed, and the spent battery residue to be treated was slowly added to the reactor to avoid excessive foam formation.

[0123] The resulting mixture was maintained for 30 minutes to 24 hours. After the first 30 minutes, if desired (depending on the type of battery residue sample and the thermal pretreatment used), one or more of the additives disclosed herein can be added to enhance recovery.

[0124] B) The suspension was then filtered to obtain a solid cake 1 of unreacted (battery) residue sample; and a clear filtrate (Filtrate 1) containing cobalt lactate, nickel lactate, and manganese lactate.

[0125] Precipitation step C) The clear filtrate (Filtrate 1) was transferred to a reactor at room temperature, and the solution was stirred for 30 min to 7 days until a precipitate was obtained.

[0126] D) The suspension obtained in step C) was then filtered to obtain a precipitate (Precipitate 1) containing cobalt lactate, nickel lactate and manganese lactate and a clear filtrate (Filtrate 2).

[0127] Regeneration of filtrate 2 Filtrate 2 can be regenerated according to the regeneration protocol herein below and optionally reused as leaching medium in step A).

[0128] Playback Protocol: 1. HPLC analysis of filtrate 2 was performed to determine the amount of each organic compound remaining in solution. Each mole of Ni, Co, or Mn precipitated removes 2 moles of lactic acid from the filtrate, which must be dosed to restore the original concentration.

[0129] The structures of the cobalt lactate, nickel lactate, and manganese lactate prepared by the process of the present invention are as follows:

[0130] TIFF0007812835000001.tif51150

[0131] Measurements were also carried out of the pH of filtrate 2. Due to the leaching reaction of some metals in the metallic state (i.e., aluminum) as defined by the following equation, there is a consumption of protons during the reaction. 2Al(s)+6H + (aq) → 2Al 3+ (aq)+3H2(g)↑

[0132] 2. Taking into account the organic compounds and pH in the solution, the amount of organic compounds required to recover the original leaching mixture and the amount of protons required to restore the original pH of the leaching mixture were determined.

[0133] 3. Addition of the amount of organic compound (lactic acid and one or more of the additives mentioned in this invention); addition of the amount of strong acid (such as HCl) measured in steps 2 and 3.

[0134] 4. The regenerated solution obtained in step 4 is ready to be used as the leaching mixture in step A) with the same organic composition and the same initial pH as the original solution.

[0135] Additional metal recovery from filtrate 2 Additional metals can be recovered from filtrate 2 by subjecting filtrate 2 to reaction conditions that allow for the precipitation of appropriate metal salts.

[0136] Lithium Recovery Protocol: A saturated aqueous solution of NaCO was added to the filtrate 2 to obtain lithium carbonate according to the process described in W. Gao et al., "Lithium Carbonate Recovery from Cathode Scrap of Spent Lithium-Ion Battery: A Closed-Loop Process," Environ. Sci. Technol., 2017, vol. 51, no. 3, pp. 1662-1669. The resulting lithium carbonate was then isolated from the reaction medium.

[0137] 1.1.2. Working Example

[0138] Example 1

[0139] Example 1 was carried out according to the general process of Alternative 1.

[0140] The spent battery residue was obtained from a mixture of portable electronic device batteries after mechanical processing, having the following composition: Black Mass (BM) (32.2g):

[0141] TIFF0007812835000002.tif17165

[0142] The infusion medium was prepared by mixing choline chloride (107 g), lactic acid (138 g), citric acid (42 g), and water (195 g). The infusion mixture therefore contained the components in the proportions shown in the table below.

[0143] TIFF0007812835000003.tif17165

[0144] Leaching step conditions (Step A): The leaching medium was rotated at 300 rpm until it reached a temperature of 55°C. Black Mass was slowly added (having a solid:liquid ratio of 1:15). The resulting mixture was maintained for 1 hour. After that, a leachate containing cobalt lactate, nickel lactate and manganese lactate was obtained.

[0145] Filtration step conditions (Step B): The suspension obtained in Step A) was then filtered through a glass microfiber filter with a pore size of 1.6 μm to obtain a solid cake 1 containing unreacted (battery) residues and a clear filtrate 1 containing cobalt lactate, nickel lactate and manganese lactate with the following metal concentrations (expressed in ppm as analyzed by ICP-OES):

[0146] TIFF0007812835000004.tif20168

[0147] Precipitation step conditions (Step C): The clear filtrate was transferred to a reactor at room temperature and stirred for 4 hours, after which cobalt lactate, nickel lactate, and manganese lactate precipitates were obtained.

[0148] Separation step conditions (Step D): The resulting suspension was filtered through a glass microfiber filter with a pore size of 1.6 μm to obtain a clear filtrate 2 and a precipitate 1 containing cobalt lactate, nickel lactate, and manganese lactate with the following metal composition (expressed as % metals analyzed by ICP-OES):

[0149] TIFF0007812835000005.tif21115

[0150] According to the metals present in precipitate 1, the recovery yields are as follows: The cobalt in the precipitate was 62.6%; The nickel content in the precipitate was 47.8%. The manganese content in the sediment is 32.3%.

[0151] Additionally, the mass balance (wt%) of cobalt, nickel and manganese in the different fractions of the process is summarized in the table below:

[0152] TIFF0007812835000006.tif28150

[0153] Therefore, the extraction yields of cobalt, nickel and manganese are calculated by the following formula: Extraction yield = Recovery yield (%) + Mass balance of leaching working solution (%) Therefore, the extraction yield is: Cobalt is 84.3% (62.6% + 21.7%) Nickel is 72.8% (47.8% + 25.0%), Manganese is 87.3% (32.3% + 55.0%).

[0154] Finally, the selectivity for cobalt, nickel or manganese is calculated by the following formula: Selectivity = 1 - [(Metal recovery) / (Remaining metal recovery)] Alternatively, the selectivity of cobalt, nickel and manganese is calculated by the following formula: Selectivity = 1 - [(Metal recovery) / (Remaining metal recovery)] Therefore, the selectivity of cobalt, nickel and manganese over the remaining metals is 75%.

[0155] Regeneration of filtrate 2 The filtrate 2 can be regenerated according to the regeneration protocol defined above and then used as leaching medium in step A).

[0156] Recovery of lithium ions from filtrate 2 Lithium in the form of lithium carbonate can be recovered from filtrate 2 according to the lithium recovery protocol defined above.

[0157] Example 2

[0158] Example 2 was carried out according to the general process of Alternative Example 1.

[0159] The spent battery residue was obtained from a mixture of portable electronic device batteries after mechanical processing, having the following composition: Black Mass (BM) (20.11 g):

[0160] TIFF0007812835000007.tif18169

[0161] The infusion medium was prepared by mixing choline chloride (34.0 g), lactic acid (43.9 g), citric acid (13.3 g), and water (258.5 g). The infusion mixture therefore contained the components in the proportions shown in the table below.

[0162] TIFF0007812835000008.tif18169

[0163] Leaching step conditions (Step A): The leaching medium was rotated at 300 rpm until it reached a temperature of 55°C. Black Mass was slowly added (having a solid:liquid ratio of 1:17). The resulting mixture was maintained for 30 minutes. Then, a mixture of 0.94 g of Cu and 0.34 g of Al metal powder (Scharlab) was added to the reactor, and the resulting mixture was maintained for 2.5 hours.

[0164] Filtration step conditions (Step B): The suspension obtained in Step A) was then filtered through a glass microfiber filter with a pore size of 1.6 μm to obtain a solid cake 1 containing unreacted (battery) residues and a clear filtrate 1 containing cobalt lactate, nickel lactate and manganese lactate with the following metal concentrations (expressed in ppm as analyzed by ICP-OES):

[0165] TIFF0007812835000009.tif19170

[0166] Precipitation step conditions (Step C): The clear filtrate was transferred to a reactor at room temperature and stirred for 48 hours, after which cobalt lactate, nickel lactate, and manganese lactate precipitates were obtained.

[0167] Separation step conditions (Step D): The resulting suspension was filtered through a glass microfiber filter with a pore size of 1.6 μm to obtain a clear filtrate 2 and a precipitate 1 containing cobalt lactate, nickel lactate, and manganese lactate with the following metal composition (expressed as % metals analyzed by ICP-OES):

[0168] TIFF0007812835000010.tif18170

[0169] According to the metals present in precipitate 1, the recovery yields are as follows: The cobalt in the precipitate is 50% The nickel content in the precipitate is 55%.

[0170] Additionally, the mass balance (wt%) of cobalt and nickel in the different fractions of the process is summarized in the table below:

[0171] TIFF0007812835000011.tif29170

[0172] Therefore, the extraction yield is: Cobalt is 93% (50% + 43%) Nickel is 94% (55% + 39%).

[0173] Regeneration of filtrate 2 The filtrate 2 can be regenerated according to the regeneration protocol defined above and then used as leaching medium in step A).

[0174] Recovery of lithium ions from filtrate 2 Lithium in the form of lithium carbonate can be recovered from filtrate 2 according to the lithium recovery protocol defined above.

[0175] Example 3

[0176] Example 3 was carried out according to the general process of Alternative Example 1.

[0177] The spent battery residue was obtained from a mixture of portable electronic device batteries after a light temperature thermomechanical process, having the following composition: Black Mass(BM) (20.13 g):

[0178] TIFF0007812835000012.tif19159

[0179] The infusion medium was prepared by mixing choline chloride (33.5 g), lactic acid (43.3 g), citric acid (13.1 g), and water (251.5 g). The infusion mixture therefore contained the components in the proportions shown in the table below.

[0180] TIFF0007812835000013.tif19130

[0181] Leaching step conditions (Step A): The leaching medium was rotated at 300 rpm until it reached a temperature of 55°C. Black Mass was slowly added (having a solid:liquid ratio of 1:17). The resulting mixture was maintained for 3 hours. After that, a leachate containing cobalt lactate, nickel lactate and manganese lactate was obtained.

[0182] Filtration step conditions (Step B): The suspension obtained in Step A) was then filtered through a glass microfiber filter with a pore size of 1.6 μm to obtain a solid cake 1 containing unreacted (battery) residues and a clear filtrate 1 containing cobalt lactate, nickel lactate and manganese lactate with the following metal concentrations (expressed in ppm as analyzed by ICP-OES):

[0183] TIFF0007812835000014.tif18168

[0184] Precipitation step conditions (Step C): The clear filtrate was transferred to a reactor at room temperature and stirred for 48 hours, after which cobalt lactate, nickel lactate, and manganese lactate precipitates were obtained.

[0185] Separation step conditions (Step D): The resulting suspension was filtered through a glass microfiber filter with a pore size of 1.6 μm to obtain a clear filtrate 2 and a precipitate 1 containing cobalt lactate, nickel lactate, and manganese lactate with the following metal composition (expressed as % metals analyzed by ICP-OES):

[0186] TIFF0007812835000015.tif21136

[0187] According to the metals present in precipitate 1, the recovery yields are as follows: The cobalt in the precipitate was 53.5% The nickel content in the precipitate is 52.2%.

[0188] Additionally, the mass balance (wt%) of cobalt and nickel in the different fractions of the process is summarized in the table below:

[0189] TIFF0007812835000016.tif26163

[0190] Therefore, the extraction yield is: Cobalt is 99.1% (53.5% + 45.6%) Nickel is 97.5% (52.2% + 45.3%).

[0191] Regeneration of filtrate 2 The filtrate 2 can be subjected to the regeneration protocol defined above and then used as leaching medium in step A).

[0192] Recovery of lithium ions from filtrate 2 Lithium in the form of lithium carbonate can be recovered from filtrate 2 according to the lithium recovery protocol defined above.

[0193] Example 4

[0194] Example 4 was carried out according to the general process of Alternative 1.

[0195] The spent battery residue was obtained from a mixture of portable electronic device batteries after mechanical processing, having the following composition: Black Mass (BM) (12.42g):

[0196] TIFF0007812835000017.tif23146

[0197] The leaching medium was prepared by mixing lactic acid (130.0 g) and water (233.0 g), so that the leaching mixture contained the components in the proportions shown in the table below.

[0198] TIFF0007812835000018.tif16162

[0199] Leaching step conditions (Step A): The leaching medium was rotated at 260 rpm until a temperature of 55°C was reached. Black Mass was slowly added (having a solid:liquid ratio of 1:29). The resulting mixture was maintained for 3 hours. After that, a leachate containing cobalt lactate, nickel lactate and manganese lactate was obtained.

[0200] Filtration step conditions (Step B): The suspension obtained in Step A) was then filtered through a glass microfiber filter with a pore size of 1.6 μm to obtain a solid cake 1 containing unreacted (battery) residues and a clear filtrate 1 containing cobalt lactate, nickel lactate and manganese lactate with the following metal concentrations (expressed in ppm as analyzed by ICP-OES):

[0201] TIFF0007812835000019.tif18164

[0202] Precipitation step conditions (Step C): The clear filtrate was transferred to a reactor at room temperature and stirred for 24 hours, after which cobalt lactate, nickel lactate, and manganese lactate precipitates were obtained.

[0203] Separation step conditions (Step D): The resulting suspension was filtered through a glass microfiber filter with a pore size of 1.6 μm to obtain a clear filtrate 2 and a precipitate 1 containing cobalt lactate, nickel lactate, and manganese lactate with the following metal composition (expressed as % metals analyzed by ICP-OES):

[0204] TIFF0007812835000020.tif18164

[0205] According to the metals present in precipitate 1, the recovery yields are as follows: The cobalt in the precipitate was 71.1%. The nickel content in the precipitate is 68.9%.

[0206] Additionally, the mass balance (wt%) of cobalt and nickel in the different fractions of the process is summarized in the table below:

[0207] JPEG0007812835000021.jpg28154

[0208] Therefore, the extraction yield is: Cobalt is 90.1% (71.1% + 19.0%) Nickel is 96.9% (68.9% + 18.0%).

[0209] Regeneration of filtrate 2 The filtrate 2 can be subjected to the regeneration protocol defined above and then used as leaching medium in step A).

[0210] Recovery of lithium ions from filtrate 2 Lithium in the form of lithium carbonate can be recovered from filtrate 2 according to the lithium recovery protocol defined above.

[0211] 1.2. Alternative 2

[0212] 1.2.1. General Process

[0213] Leaching step A) The leaching medium was prepared by mixing solid and / or liquid organic compounds with deionized water at the appropriate dilution ratio. The leaching medium thus obtained was placed in a 500 ml jacketed reactor equipped with a heat control and coil condenser to prevent evaporation, and the anchor impeller rotated at 300 rpm until the desired temperature was reached. The mixture was maintained at the same stirring speed, and the spent battery residue to be treated was slowly added to the reactor to avoid excessive foam formation.

[0214] The resulting mixture was maintained for 30 minutes to 24 hours. After the first 30 minutes, if desired (depending on the type of battery residue sample), one or more of the additives disclosed herein can be added to enhance recovery.

[0215] Precipitation step E) The resulting mixture was then cooled to room temperature and kept stirring for 30 minutes to 7 days until precipitation of cobalt lactate, nickel lactate, manganese lactate, or a mixture thereof was obtained.

[0216] F) The suspension obtained in step E) is then filtered through a glass microfiber filter with a pore size of 1.6 μm to obtain a solid cake 2 containing cobalt lactate, nickel lactate, manganese lactate or a mixture thereof and the unreacted (battery) residue sample, and a clear filtrate 3 containing most of the metals present in the original battery sample (e.g., Cu, Al, Mn, and Fe) with small amounts of unprecipitated Co and Ni.

[0217] G) The solid cake 2 obtained in step F) was washed with water to obtain a solid cake 3 containing the unreacted (battery) residue sample and a clear filtrate 4 containing cobalt lactate, nickel lactate, manganese lactate or a mixture thereof.

[0218] The aqueous filtrate 4 thus obtained can be dried overnight at 80°C to obtain a dry solid containing cobalt lactate, nickel lactate, manganese lactate or a mixture thereof.

[0219] Regeneration of filtrate 3 The filtrate 3 can be regenerated according to the regeneration protocol defined above and then used as leaching medium in step A).

[0220] Additional metal recovery from filtrate 3 Additional metals can be recovered from filtrate 3 by subjecting filtrate 3 to reaction conditions that allow for the precipitation of appropriate metal salts.

[0221] Recovery of lithium ions from filtrate 3 Lithium in the form of lithium carbonate can be recovered from Filtrate 3 according to the lithium recovery protocol as defined above for Filtrate 2, but using Filtrate 3 instead of Filtrate 2.

[0222] 1.2.2. Working Example

[0223] Example 5

[0224] Example 5 was carried out according to the general process of Alternative Example 2.

[0225] The spent battery residue was obtained from a mixture of portable electronic device batteries after mechanical processing, having the following composition: Black Mass (BM) (44.4g):

[0226] TIFF0007812835000022.tif18167

[0227] The infusion medium was prepared by mixing choline chloride (74 g), lactic acid (95 g), citric acid (29 g), and water (202 g). The infusion mixture therefore contains the components in the proportions shown in the table below.

[0228] TIFF0007812835000023.tif18167

[0229] Leaching step conditions (Step A): The leaching medium was rotated at 300 rpm until it reached a temperature of 55°C. Black Mass was slowly added (having a solid:liquid ratio of 1:9). The resulting mixture was maintained for 5 hours without adding any additional additives.

[0230] Precipitation step conditions (Step E): The reactor was then turned off and the mixture was cooled, and stirring was maintained for 0.5 hours until a precipitate was obtained. The resulting suspension was filtered (Step F) to separate the unreacted cobalt lactate, nickel lactate, and manganese lactate compounds and battery residue. Black Mass and a clear filtrate 3 containing the following metal concentrations (expressed in ppm):

[0231] TIFF0007812835000024.tif21170

[0232] The solid cake 2 was washed with 1 l of deionized water (step G) to give 12.7 g of solid cake 3 containing unreacted BM with the following metal concentrations (expressed in % by weight relative to the weight of the residue):

[0233] TIFF0007812835000025.tif17169

[0234] According to the metals present in solid cake 2, the recovery yields are as follows: Cobalt is 80% Nickel is 71% Manganese is XX%.

[0235] Additionally, the mass balance (wt%) of cobalt, nickel and manganese in the different fractions of the process is summarized in the table below:

[0236] TIFF0007812835000026.tif30169

[0237] Therefore, the extraction yield is: Cobalt is 99% (80% + 19%) Nickel is 95% (71% + 24%) Manganese is 99.5% (48.8% + 50.7%).

[0238] Additionally, the selectivity of cobalt, nickel, and manganese relative to the remaining metals is 76%.

[0239] Regeneration of filtrate 3 The filtrate 3 can be subjected to the regeneration protocol defined above and then used as leaching medium in step A).

[0240] Recovery of lithium ions from filtrate 3 Lithium in the form of lithium carbonate can be recovered from Filtrate 3 according to the lithium recovery protocol as defined above for Filtrate 2, but using Filtrate 3 instead of Filtrate 2.

[0241] Example 6

[0242] Example 6 was carried out according to the general process of Alternative Example 2.

[0243] The spent battery residue was obtained from a mixture of portable electronic device batteries after mechanical processing, having the following composition: Black Mass (BM) (12.4g):

[0244] TIFF0007812835000027.tif20161

[0245] The leaching medium was prepared by mixing lactic acid (130.0 g) and water (233.0 g), so that the leaching mixture contained the components in the proportions shown in the table below.

[0246] TIFF0007812835000028.tif20161

[0247] Leaching step conditions (Step A): The leaching medium was rotated at 240 rpm until it reached a temperature of 55°C. Black Masswas slowly added (having a solid:liquid ratio of 1:9). The resulting mixture was maintained for 6.7 hours without adding any additional additives.

[0248] Precipitation step conditions (Step E): The reactor was then turned off and the mixture was cooled, and stirring was maintained for 24 hours until a precipitate was obtained. The resulting suspension was filtered (Step F) to separate the unreacted cobalt lactate, nickel lactate, and manganese lactate compounds and battery residue. Black Mass and a clear filtrate 3 containing the following metal concentrations (expressed in ppm):

[0249] TIFF0007812835000029.tif21147

[0250] The solid cake 2 was washed with 1 l of deionized water (step G) to give 2.8 g of solid cake 3 containing unreacted BM with the following metal concentrations (expressed in % by weight relative to the weight of the residue):

[0251] TIFF0007812835000030.tif20165

[0252] According to the metals present in solid cake 2, the recovery yields are as follows: Cobalt is 79.1% Nickel is 75.2% Manganese is 45%.

[0253] Additionally, the mass balance (wt%) of cobalt, nickel and manganese in the different fractions of the process is summarized in the table below:

[0254] TIFF0007812835000031.tif26117

[0255] Therefore, the extraction yield is: Cobalt is 98.1% (79.1% + 19%) Nickel is 93.2% (75.2% + 18%), Manganese is 99% (54% + 45%).

[0256] Additionally, the selectivity of cobalt, nickel, and manganese relative to the remaining metals is 84%.

[0257] Regeneration of filtrate 3 The filtrate 3 can be subjected to the regeneration protocol defined above and then used as leaching medium in step A).

[0258] Recovery of lithium ions from filtrate 3 Lithium in the form of lithium carbonate can be recovered from Filtrate 3 according to the lithium recovery protocol as defined above for Filtrate 2, but using Filtrate 3 instead of Filtrate 2.

[0259] B) Catalyst

[0260] 1.2. Alternative Example 1

[0261] 1.2.1. General Process

[0262] The process of leaching, precipitation and regeneration of the spent solution is carried out in a similar manner to that disclosed above for the battery.

[0263] 1.2.2. Working Example

[0264] Example 7

[0265] Example 7 was carried out according to the general process of Alternative Example 1.

[0266] The spent catalyst residue was a CoMo hydrodesulfurization (HDS) catalyst (80.1 g) after a crushing process (<250 μm) with the following composition:

[0267] TIFF0007812835000032.tif18157

[0268] The infusion medium was prepared by mixing choline chloride (34.2 g), lactic acid (44.1 g), citric acid (13.4 g), and water (257 g). The infusion mixture therefore contained the components in the proportions shown in the table below.

[0269] TIFF0007812835000033.tif18157

[0270] Leaching step conditions (Step A): The leaching medium was rotated at 300 rpm until it reached a temperature of 55°C. The catalyst powder material was slowly added (with a solid:liquid ratio of 1:4.4). The resulting mixture was maintained for 3 hours. After that, a leaching solution containing cobalt lactate and other impurity metals was obtained.

[0271] Filtration step conditions (Step B): After that time, the suspension obtained in Step A) was filtered through a glass microfiber filter with a pore size of 1.6 μm to obtain a solid cake 1 containing unreacted (catalytic) residues and a clear filtrate 1 containing cobalt lactate, containing the following metal concentrations (expressed in ppm as analyzed by ICP-OES):

[0272] TIFF0007812835000034.tif22165

[0273] According to the above metal composition, the metal leaching yields (expressed as % metals analyzed by ICP-OES) are as follows:

[0274] TIFF0007812835000035.tif22156

[0275] The leaching selectivity of Co relative to the other major metals (Al and Mo) is as follows:

[0276] TIFF0007812835000036.tif22114

[0277] The precipitation step can be carried out according to the same process as disclosed in the previous example battery. Optionally, the precipitation step can include a recycling step to increase the cobalt lactate content in the leachate and promote a higher precipitation rate.

[0278] List of cited references W. Gao et al., ``Lithium Carbonate Recovery from Cathode Scrap of Spent Lithium-Ion Battery: A Closed-Loop Process,'' Environ.Sci.Technol., 2017, vol. 51, no. 3, pp. 1662-1669.

Claims

1. 1. A process for recovering one or more metal ions selected from the group consisting of cobalt, nickel, manganese and mixtures thereof from a metal-containing residue, comprising: A) leaching the residue with a leaching solution containing lactic acid to obtain a leaching mixture formed by a filtrate 1 containing cobalt lactate, nickel lactate, manganese lactate or a mixture thereof and a solid cake 1; B) separating the filtrate 1 from the leaching mixture obtained in step A); C) precipitating cobalt lactate, nickel lactate, manganese lactate or a mixture thereof from the filtrate 1 obtained in step B) to obtain a precipitate mixture formed by filtrate 2 and precipitate 1 containing cobalt lactate, nickel lactate, manganese lactate or a mixture thereof; D) separating the precipitate 1 comprising cobalt lactate, nickel lactate, manganese lactate or a mixture thereof from the precipitation mixture obtained in step C); Contains, or A) leaching the residue with a leaching solution containing lactic acid to obtain a leaching mixture formed by a filtrate 1 containing cobalt lactate, nickel lactate, manganese lactate or a mixture thereof and a solid cake 1; E) precipitating cobalt lactate, nickel lactate, manganese lactate or a mixture thereof from the filtrate 1 obtained in step A) to obtain a precipitation mixture formed by a filtrate 3 and a solid cake 2 containing cobalt lactate, nickel lactate, manganese lactate or a mixture thereof; F) separating the solid cake 2 from the precipitation mixture obtained in step E); G) separating cobalt lactate, nickel lactate, manganese lactate or a mixture thereof from the solid cake 2; Including, The process involves using lactic acid as a leaching agent and precipitant; and Each of the steps C) and E) of obtaining a precipitate is carried out at a pH of 1.5 to 5. ,process.

2. 2. The process of claim 1, wherein the residue is selected from the group consisting of spent batteries, metal alloys and metal catalysts, in particular batteries.

3. 3. The process of claim 1 or 2, wherein the residue is selected from a cobalt-containing residue, a nickel-containing residue, a manganese-containing residue, a cobalt and nickel-containing residue, a cobalt and manganese-containing residue, a nickel and manganese-containing residue, and a cobalt, nickel and manganese-containing residue.

4. The filtrate 2 obtained in step D) is used as the leaching solution in step A), or 2. The process according to claim 1, wherein the filtrate 3 obtained in step F) is used as the leaching solution in step A).

5. 2. The process of claim 1, wherein the residue is in the form of black mass.

6. 10. The process of claim 1, wherein the leaching solution further comprises one or more organic acids, one or more reducing agents, one or more proton acceptors, one or more solvents and mixtures thereof.

7. 10. The process of claim 1, wherein the leaching solution comprises 10 to 40 wt. % lactic acid based on the total weight of the leaching solution.

8. The leaching solution - consisting of lactic acid and water, or - Contains lactic acid, choline chloride, citric acid and water, The process of claim 1.

9. The leaching solution 10 to 40% by weight of lactic acid based on the total weight of the leaching solution; 5 to 30% choline chloride based on the total weight of the leaching solution; 2 to 11% by weight of citric acid based on the total weight of the leaching solution; Sufficient water to make up to 100% by weight; 9. The process of claim 8, comprising:

10. 10. The process of claim 1, wherein each of steps A, C, and E is carried out at a temperature of from 20°C to 100°C.

11. 2. The process of claim 1, wherein the weight relationship between the residue and the leach solution in step A is from 1:5 to 1:

70.

12. Each of the separating steps B), D) and F) is carried out by filtration; The separating step G) is carried out by mixing the solid cake 2 obtained in step F) with a solvent selected from water and mixtures of water with one or more miscible organic solvents; The process of claim 1.

13. the recovery rate of cobalt ions from the residue is 50% by weight or more; the recovery rate of nickel ions from the residue is 48% by weight or more; The recovery rate of manganese ions from the residue is 32% by weight or more. The process of claim 1.

14. The extraction yield of cobalt ions is 80% by weight or more, The extraction yield of nickel ions is higher than 73% by weight, The extraction yield of manganese ions is higher than 87% by weight. The process of claim 1.

15. 10. The process of claim 1, further comprising the additional step of adding one or more additives selected from the group consisting of reducing agents and oxidizing agents to the resulting leaching mixture obtained in step A).

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