Processing black mass derived from lithium ion battery materials

Abstract

The present invention relates to the recycling of used lithium ion batteries and provides a method for processing black mass derived from lithium ion battery materials.

Description

[0001] BASF SE B25.131P-WO 67056 Ludwigshafen am Rhein 14.01 ,2026 / lg / np / jl

[0002] Processing black mass derived from lithium ion battery materials Field of the invention

[0003] The present invention relates to the recycling of used lithium ion batteries and provides a method for processing black mass derived from lithium ion battery materials.

[0004] Background

[0005] Lithium ion battery materials contain valuable metals such as lithium, aluminum, copper, nickel, cobalt, and / or manganese that can be recovered and recycled to conserve natural resources. Processes for recycling lithium ion battery materials generally comprise mechanical comminution of lithium ion batteries, lithium ion battery waste, lithium ion battery production scrap, lithium ion cell production scrap, or lithium ion cathode active material to obtain black mass, a particulate material comprising the active components of the battery electrodes such as graphite and cathode active material, which may also include impurities from the casing, electrode foils, cables, separator, and electrolyte. The black mass then is further processed to recover the valuable metals, for instance, by hydrometallurgical treatment.

[0006] WO 20231054621 A1 discloses a method for recovering valuable metals from waste lithium ion batteries comprising a dissolution step for dissolving an active material powder obtained by pre-treating the waste lithium-ion batteries in a mineral acid to obtain an acid solution; and a solvent extraction step for separating manganese, cobalt, and nickel, among metals contained in the active material powder, from the acid solution through solvent extraction to obtain a first lithium salt aqueous solution as a residual liquid of the solvent extraction.WO 2020 / 124130 A1 discloses a method for the recovery of metals from a feed stream containing one or more value metals and lithium. The method comprises subjecting the feed stream to a sulfuric acid leach to form a slurry comprising a pregnant leach solution of soluble metal salts and a solid residue; separating the pregnant leach solution and the solid residue; subjecting the pregnant leach solution to one or more separate solvent extraction steps, wherein each solvent extraction step recovers one or more value metals from the pregnant leach solution, the remaining pregnant leach solution comprising lithium; and recovery of lithium from the pregnant leach solution.

[0007] CN 114 655 969 A discloses a method for preparing battery-grade lithium carbonate and iron phosphate by recovering high-impurity lithium iron phosphate positive electrode waste. According to the method, chlorides of iron or copper are added in the air water leaching process, and efficient selective leaching of lithium and synchronous leaching of impurity aluminum are achieved. The method comprises the following steps: extracting lithium from iron phosphorus slag, leaching iron and phosphorus from the iron phosphorus slag with an acid solution, removing copper, nickel, cobalt and the like from a leaching solution by sulfuration precipitation, directly evaporating and crystallizing the purified solution at 100°C without adjusting the pH value to obtain iron phosphate dihydrate, condensing gas generated by evaporating and crystallizing, mixing with crystallization mother liquor, and carrying out acid leaching on the next batch of iron phosphorus slag.

[0008] Black mass obtained by mechanical comminution of lithium ion batteries may comprise metallic copper from electrode foils. Copper dissolution in the leaching stage requires the use of oxidants, many of which introduce unwanted species into the pregnant leach solution or require additional safety precautions.

[0009] It is an object of the present disclosure to provide an improved recycling process for black mass derived from lithium ion battery materials.Summary of the invention

[0010] The present disclosure provides a process for treating black mass from lithium ion battery materials. Copper sulfate is introduced into an aerobic leaching step of black mass comprising metallic copper, e.g., black mass derived from nickel-cobalt-manganese oxide (NCM) battery materials, in an amount to achieve a ratio of Cu2+:Cu° in the range from 0.01:1 to 2:1. A comproportionation of Cu° and Cu2+to Cu+is induced by the addition of copper sulfate, which in turn makes metallic copper more accessible to oxidation with solubilized O2. Leaching of copper from the black mass is accelerated and no additional impurities are introduced into the black mass recycling process.

[0011] In some embodiments of the process, copper sulfate is introduced via an acidic aqueous solution obtained by leaching black mass derived from Fe-based battery materials, for instance, lithium iron phosphate (LFP) or lithium iron manganese phosphate (LFMP) battery materials, with sulfuric acid.

[0012] Brief description of the drawings

[0013] Fig. 1 shows a flow diagram of an embodiment of the process of the present disclosure

[0014] Fig. 2 is a comparison of copper dissolution from black mass with and without addition of copper sulfate,

[0015] Detailed description

[0016] The present disclosure provides a process for treating black mass from lithium ion battery materials. The process comprises dispersing black mass comprising metallic copper in water to produce a slurry, adding an aqueous solution comprising Cu2+and SCU2' to the slurry, such that the ratio of Cu2+:Cu° in the slurry is in the range from 0.01 :1 to 2:1 , optionally leaching the dispersed black mass with sulfuric acid under inert atmosphere, and subsequently leaching the dispersed black mass with sulfuric acid while injecting air into the mixture, thereby dissolving metallic copper present in the black mass and obtaining a pregnant leach solution.In some embodiments, the black mass comprising metallic copper is derived from nickel-cobalt-manganese oxide (NCM) battery materials. In other embodiments, the black mass comprising metallic copper is derived from lithium cobalt oxide (LiCoCh) battery materials. In yet other embodiments, the black mass comprising metallic copper is derived from lithium manganese oxide (LiMn2O4 spinel, or Li2MnO3-based lithium-rich layered materials, LMR-NMC) battery materials. In still other embodiments, the black mass comprising metallic copper is derived from lithium nickel cobalt aluminum oxides (LiNixCoyAIzCh with x + y + z = 1 or NCA) battery materials.

[0017] In the present disclosure, the term “black mass” refers to materials derived from, for example, a lithium ion battery, lithium ion battery waste, lithium ion battery production scrap, lithium ion cell production scrap, lithium ion cathode active material, and / or combinations thereof by mechanical processes such as mechanical comminution. For example, black mass may be derived from battery scrap by mechanically treating the battery scrap to obtain the active components of the electrodes such as graphite and cathode active material and may include impurities from the casing, electrode foils, cables, separator, and electrolyte. In some examples, the battery scrap may be subjected to a heat treatment to pyrolyze organic (e.g., electrolyte) and polymeric (e.g., separator and binder) materials. Such a heat treatment may be performed before or after mechanical comminution of the battery material.

[0018] Lithium ion batteries can comprise a variety of different cathode materials, for instance, lithium cobalt oxide (LiCoCh), lithium iron phosphate (LiFePCU or LFP), lithium manganese oxide (LiMn2O4 spinel, or Li2MnO3-based lithium-rich layered materials, LMR-NMC), lithium nickel manganese cobalt oxide (LiNiMnCoCh or NMC) and lithium nickel cobalt aluminum oxides (LiNixCoyAIzCh with x + y + z = 1 or NCA).

[0019] Lithium ion batteries may be disassembled, after discharging and optionally drying them, punched, milled, for example in a hammer mill, and / or shredded, for example in an industrial shredder. From this kind of mechanical processingthe active material of the battery electrodes may be obtained. A light fraction such as housing parts made from organic plastics and aluminum foil or copper foil may be removed, for example, in a forced stream of gas, air separation or classification.

[0020] Battery scraps may stem from, e.g., used batteries or from production waste such as off-spec material. In some embodiments a battery material is obtained from mechanically treated battery scraps, for example from battery scraps treated in a hammer mill or in an industrial shredder. Such material may have an average particle diameter (D50) ranging from 1 pm to 1 cm, such as from 1 pm to 500 pm, for example, from 3 to 250 pm.

[0021] Larger parts of the battery scrap like the housings, the wiring and the electrode carrier films may be separated mechanically such that the corresponding materials may be excluded from the battery material that is employed in the process.

[0022] Mechanically treated battery scrap may be subjected to a solvent treatment to dissolve and separate polymeric binders used to bind the transition metal oxides to current collector films, or, e.g., to bind graphite to current collector films. Suitable solvents are N-methylpyrrolidone, N,N-dimethyl-formamide, N,N-dimethylacetamide, N-ethylpyrrolidone, and dimethylsulfoxide, in pure form, as mixtures of at least two of the foregoing, or as a mixture with 1 % to 99 % by weight of water.

[0023] Mechanically treated battery scrap may be subjected to a heat treatment in a wide range of temperatures under different atmospheres. The temperature range is usually in the range of 100°C to 900°C. Lower temperatures below 300°C may serve to evaporate residual solvents from the battery electrolyte, at higher temperatures the binder polymers may decompose while at temperatures above 400°C the composition of the inorganic materials may change as some transition metal oxides may become reduced either by the carbon contained in the scrap material or by introducing reductive gases. Insome embodiments, a reduction of lithium metal oxides may be avoided by keeping the temperature below 400°C and / or by removing carbonaceous materials before the heat treatment.

[0024] In some embodiments, the battery material comprises at least one chosen from lithiated nickel cobalt manganese oxide, lithiated nickel cobalt aluminum oxide, lithium metal phosphate, lithium ion battery scrap, black mass derived from a lithium ion battery, and combinations there.

[0025] In some embodiments, the battery material comprises lithium metal phosphate of formula LixMPCU, wherein x is an integer greater than or equal to one, and M is chosen from metals, transition metals, rare earth metals, and combinations thereof. Examples include lithium iron phosphate (LiFePCU or LFP) and lithium iron manganese phosphate (LFMP).

[0026] In some embodiments, the battery material comprises lithiated nickel cobalt manganese oxide of formula Lii+x(NiaCobMncM1d)i-xO2, wherein M1 is chosen from Mg, Ca, Ba, Al, Ti, Zr, Zn, Mo, V and Fe, zero < x < 0.2, 0.1 < a < 0.95, zero < b < 0.9 (such as 0.05 < b < 0.5), zero < c < 0.6, zero < d < 0.1 , and a + b + c + d = 1. Exemplary lithiated nickel cobalt manganese oxides include Li(i+x)[Nio.33Coo.33Mno.33](i-x)02, Li(i+x)[Nio.5Coo.2Mno.3](i-x)02, Li(i+x)[Nio.6Coo.2Mno.2](i-x)02, Li(i+X)[Nio.7Coo.2Mno.3](i-x)02, Li(i+x)[Nio.8Coo.iMno.i](i-x)02 each with x as defined above, and Li[Nio.85COo.13Alo.02]02.

[0027] In some embodiments, the battery material comprises lithiated nickel-cobalt aluminum oxides of formula Li[NihCo lj]O2+r, wherein h ranges from 0.8 to 0.90, i ranges from 0.1 to 0.3, j ranges from 0.01 to 0.10, and r ranges from zero to 0.4.

[0028] In some embodiments, the battery material comprises nickel, cobalt, manganese, copper, aluminum, iron, phosphorus, or combinations thereof.In some embodiments, the battery material comprises LixMO2 wherein x is an integer greater than or equal to one, and M is chosen from metals, transition metals, rare earth metals, and combinations thereof.

[0029] The process of the present disclosure comprises dispersing black mass comprising metallic copper in water to produce an aqueous slurry of black mass particles. In some embodiments of the process, an aqueous slurry of black mass with a solids content in the range of from 10 wt% to 50 wt%, for instance, 20 wt% to 40 wt%, e.g., 20 wt% to 30 wt%, relative to the total weight of the aqueous slurry, is produced.

[0030] In the process of the present disclosure, an aqueous solution comprising Cu2+and SO42’ is added to the slurry, such that the ratio of Cu2+:Cu° in the slurry is in the range from 0.01:1 to 2:1, e.g., 0.1:1 to 1:1, for instance, 0.2:1 to 1:1, or 0.5:1 to 1.0:1.

[0031] In some embodiments of the process, the concentration of SO42’ in the pregnant leach solution does not exceed 250 g / l. 1 mol of SO42’ corresponds to 96 g. The concentration limit is chosen to avoid precipitation of metal sulfates from the solution. On the other hand, higher concentrations favorably affect space-time yield of the process. In some embodiments, the concentration of SO42-in the slurry does not exceed the solubility limit of sulfate in the pregnant leach solution.

[0032] In some embodiments of the process, the aqueous solution comprising Cu2+and SO42’ replaces a fraction of the water required to produce the slurry. In some embodiments, up to 30% of the water is replaced by the aqueous solution comprising Cu2+and SO42’. In other embodiments of the process, the amount of aqueous solution comprising Cu2+and SO42’ added to the dispersion is such that the concentration of value metals such as nickel and / or cobalt and / or manganese is reduced by less than 20%, for instance, less than 10%, e.g., less than 5%, relative to the concentration of the respective metal in the slurry without addition of the aqueous solution comprising Cu2+and SO42’. Restrictingthe volume added reduces decrease of the concentration of valuable metals in the slurry.

[0033] In some embodiments of the process, the aqueous solution comprising Cu2+and SO42’ also comprises Li+. Increasing the lithium content of the slurry facilitates recovery of lithium from the pregnant leach solution (PLS) obtained after leaching black mass with sulfuric acid. In some embodiments of the process, the concentration of Li+in the aqueous solution comprising Cu2+and SO42’ is in the range of from 0.05 wt% to 2.0 wt%, e.g., 0.3 wt% to 0.9 wt%, relative to the total weight of the aqueous solution.

[0034] In some embodiments of the process, the aqueous solution comprising Cu2+and SO42-also comprises iron and phosphorus. In some embodiments, the concentration of iron and phosphorus in the aqueous solution comprising Cu2+and SO42-is not more than 0.5 wt% each, relative to the total weight of the aqueous solution. It is preferable to limit the increase of iron and phosphorus concentration in the PLS from the black mass comprising metallic copper, as these elements subsequently have to be removed from the PLS. In some embodiments, the concentration of iron in the PLS is limited to less than 0.9 wt% Fe, e.g., not more than 0.45 wt%, and the concentration of phosphorus in the PLS is limited to not exceed 0.6 wt%, e.g., to 0.3 wt% or less.

[0035] In some embodiments of the process, the aqueous solution comprising Cu2+and SO42-has been obtained by leaching black mass derived from lithium iron phosphate (LFP) batteries and / or from lithium iron manganese phosphate (LFMP) batteries with sulfuric acid.

[0036] The process of the present disclosure further comprises an optional step of leaching the dispersed black mass comprising metallic copper with sulfuric acid under inert atmosphere ("inert leaching"). Examples of suitable inert gases used to generate the inert atmosphere include nitrogen, argon, and water vapor. Inert leaching is performed as a safety measure, as hydrogen may evolve when treating the black mass comprising metallic copper with sulfuric acid, inparticular, when pyrolyzed black mass comprising metallic copper is used in the process of the present disclosure.

[0037] The process of the present disclosure further comprises leaching the dispersed black mass comprising metallic copper with sulfuric acid while injecting air into the mixture ("oxidative leaching"), thereby dissolving metallic copper present in the black mass. The presence of copper sulfate in the leaching step induces comproportionation of Cu° and Cu2+to Cu+, facilitating the oxidation of metallic copper with solubilized O2. Leaching of copper from the black mass is accelerated and no additional impurities are introduced into the black mass recycling process, as might be the case when using other oxidants.

[0038] The present disclosure also provides a process for treating black mass comprising metallic copper, the black mass being derived from lithium ion battery materials comprising nickel and / or cobalt and / or manganese.

[0039] In some embodiments, the black mass comprising metallic copper is derived from nickel-cobalt-manganese oxide (NCM) battery materials. In other embodiments, the black mass comprising metallic copper is derived from lithium cobalt oxide (LiCoCh) battery materials. In yet other embodiments, the black mass comprising metallic copper is derived from lithium manganese oxide (LiMn2O4 spinel, or Li2MnO3-based lithium-rich layered materials, LMR-NMC) battery materials. In still other embodiments, the black mass comprising metallic copper is derived from lithium nickel cobalt aluminum oxides (LiNixCoyAIzCh with x + y + z = 1 or NCA) battery materials.

[0040] The process comprises

[0041] a) dispersing the black mass in water,

[0042] b) adding an acidic aqueous solution comprising copper(ll) cations and lithium cations obtained in step i) to the dispersion,

[0043] c) optionally, leaching the dispersed black mass with sulfuric acid under inert atmosphere, and subsequentlyd) leaching the black mass with sulfuric acid while injecting air into the mixture, and

[0044] e) separating solids from the mixture to obtain an aqueous acidic solution comprising lithium cations and copper cations, as well as nickel cations and / or cobalt cations and / or manganese cations, f) removing copper cations from the aqueous acidic solution,

[0045] g) adjusting the pH of the aqueous acidic solution depleted of copper cations obtained in step f) to be in the range of from 3.0 to 4.0, and generating a precipitate,

[0046] h) recovering the precipitate obtained in step g) and optionally recycling the precipitate into step i),

[0047] i) leaching black mass derived from lithium iron phosphate battery materials and / or lithium iron manganese phosphate battery materials with sulfuric acid under oxidative conditions to obtain an acidic aqueous solution comprising copper(ll) cations and lithium cations.

[0048] The process comprises a) dispersing the black mass comprising metallic copper in water and b) adding an acidic aqueous solution comprising copper(ll) cations and lithium cations obtained in step i), i.e. , obtained by leaching black mass derived from lithium iron phosphate (LFP) battery materials and / or from lithium iron manganese phosphate (LFMP) battery materials with sulfuric acid. In some embodiments of the process, an aqueous slurry of black mass with a solids content in the range of from 10 wt% to 50 wt%, for instance, 20 wt% to 40 wt%, e.g., 20 wt% to 30 wt%, relative to the total weight of the aqueous slurry, is produced by steps a) and b).

[0049] The process further comprises an optional step c) of leaching the dispersed black mass comprising metallic copper with sulfuric acid under inert atmosphere (inert leaching). In the context of the present disclosure, inert atmosphere means that the gas phase does not react with the solids and liquids present in the leaching step, i.e., neither oxidizes nor reduces the black mass nor any metal cations solubilized by the sulfuric acid. Examples of suitable inert gases used to generate the inert atmosphere include nitrogen, argon, and water vapor.In some embodiments, the inert atmosphere mainly comprises water vapor. Small amounts of air and / or hydrogen produced by reaction of black mass with sulfuric acid may be present. Inert leaching is performed as a safety measure, as hydrogen may evolve when treating the black mass comprising metallic copper with sulfuric acid, in particular, when pyrolyzed black mass comprising metallic copper is used in the process of the present disclosure. At least at the end of the inert leaching step, the concentration of hydrogen in the gas phase is below the lower explosion limit. The optional inert leaching step c) is performed at a temperature of from 70°C to 95°C, for a time of from 0.5 to 4 hours, for instance, from 1 to 2 hours, and at an acid concentration of from 0.7 kg to 2 kg acid per kg black mass.

[0050] The process further comprises d) leaching black mass comprising metallic copper, e.g., black mass derived from NCM battery materials, with sulfuric acid while injecting air into the mixture ("oxidative leaching").

[0051] In some embodiments, oxidative leaching is performed at a temperature of from 70°C to 95°C, for instance, from 85°C to 90°C, for a time of from 1 to 5 hours (2-4), and at a pH of from 0.5 to 2.5, e.g., 1 to 1.5. It has been found that the temperature range is crucial for achieving quantitative leaching of copper within the given residence time when no Cu2+is added. If a temperature higher than 90°C is employed, incomplete leaching of copper is observed. The addition of Cu2+promotes the dissolution of metallic copper, so that higher temperatures and shorter reaction times can be used in the process of the present disclosure. Still, at temperatures of less than 70°C, leaching is slow and is not completed during the given residence time.

[0052] In some embodiments of the process of the present disclosure, the amount of the acidic aqueous solution comprising copper(ll) cations and lithium cations and iron cations added is such that the ratio of Cu2+present in the solution to Cu° present in the black mass is in the range from 0.01 :1 to 2:1 , e.g., 0.1 to 1.5, for instance, 0.5 to 1.0. It has been found that the ratio of Cu2+:Cu° is crucial for accelerating leaching of copper from the black mass.In some embodiments of the process, the mixture obtained after oxidative leaching is further leached with sulfuric acid while a sulfur-containing reducing agent is added to the mixture ("reductive leaching"). In an embodiment of the process, up to 2.0 mol / L of the sulfur-containing reducing agent per mol of Ni, Co, Mn present in the mixture are added to the reaction mixture. The sulfur-containing reducing agent may be solid, liquid or gaseous. Examples of solid sulfur-containing reducing agents include Na2SO3, and Na2S20s. Examples of liquid sulfur-containing reducing agents include H2SO3. Examples of gaseous sulfur-containing reducing agents include SO2. In some embodiments, the sulfur-containing reducing agent is selected from the group consisting of sulfur dioxide, H2SO3, Na2SO3, and Na2S20s. In some embodiments, the sulfur-containing reducing agent is sulfur dioxide.

[0053] When sulfur dioxide is injected into the mixture in the reductive leaching step, sulfur dioxide is added to the reaction mixture until it breaks through, i.e. , sulfur dioxide can be detected in the reactor exhaust. In an embodiment of the process, up to 2.0 mol / L sulfur dioxide per mol of Ni, Co, Mn are added to the reaction mixture.

[0054] The reductive leaching step is performed at a temperature of 70°C to 95°C, for a time of from 1 to 2 h, and at pH of from 0.5 to 2.0, for instance, from 1 to 1.7.

[0055] Subsequently, in step e) solids are removed from the mixture obtained after the last step in the sequence of leaching steps to obtain an aqueous acidic solution comprising lithium cations and copper cations, as well as nickel cations and / or cobalt cations and / or manganese cations.

[0056] Subsequently, in step f) copper cations are removed from the aqueous acidic solution.

[0057] In some embodiments of the process, copper cations are removed in step f) from the aqueous acidic solution by solvent extraction, after the pH of thesolution obtained in step e) has been adjusted to be in the range of from 1.5 to 2.5.

[0058] Solvent extraction is performed using a solvent comprising a suitable extractant for copper ions. In some embodiments, the copper ions are removed from the solution by extraction with a 1:1 (by volume) mixture of 2-hydroxy-5-nonyl-acetophenone ketoxime and 5-nonylsalicylaldoxime (LIX 984N). In some embodiments of the process, the copper ions removed from the solution by solvent extraction in step f) are subsequently reduced to metallic copper.

[0059] In other embodiments of the process, copper cations are removed in step f) from the aqueous acidic solution by precipitating copper sulfide and subsequently separating the precipitate from the aqueous acidic solution.

[0060] In yet other embodiments, the copper ions are removed in step f) by cementation. In still other embodiments, the copper ions are removed by electrolysis, reducing them to metallic copper (electrowinning).

[0061] Subsequently, g), the pH of the aqueous solution depleted of copper cations obtained in step f) is adjusted to be in the range of from 3.0 to 4.0 by addition of a base such as Na2CO3, Ca(OH)2, CaCOs, CaO, or NaOH, generating a precipitate which comprises impurity cations of the group consisting of Al and Fe and impurity anions comprising P, F, Al, and / or Si present in the solution.

[0062] In step h) of the process, the precipitate obtained in step g) is recovered and optionally recycled into step i). As the precipitate may contain substantial amounts of co-precipitated nickel, cobalt, and / or lithium, recycling the precipitate into step i) increases the overall yield of these elements, as they are subsequently re-introduced into step b). The mother liquor obtained in step g) is an acidic aqueous solution comprising nickel, cobalt, manganese, and lithium ions.In step i) of the process, black mass derived from lithium iron phosphate (LFP) battery materials and / or from lithium iron manganese phosphate (LFMP) battery materials is leached with sulfuric acid, optionally under oxidative conditions, to obtain an acidic aqueous solution comprising copper(ll) cations and lithium cations, which is added in step b) to the dispersion comprising black mass comprising metallic copper. In some embodiments, the concentration of iron in the acidic aqueous solution comprising copper(ll) cations and lithium cations is limited to less than 0.9 wt% Fe, e.g., not more than 0.45 wt%, and the concentration of phosphorus in the acidic aqueous solution comprising copper(ll) cations and lithium cations is limited to not exceed 0.6 wt%, e.g., to 0.3 wt% or less.

[0063] In some embodiments of the process, leaching of the black mass derived from lithium iron phosphate (LFP) battery materials and / or from lithium iron manganese phosphate (LFMP) battery materials is performed at a temperature of from 70°C to 100°C, for instance, from 80°C to 98°C, for a time of from 2 to 5 hours, and at a pH of from 0.5 to 3.0, e.g., 1.0 to 2.0.

[0064] In some embodiments of the process, leaching of the black mass derived from lithium iron phosphate (LFP) battery materials and / or from lithium iron manganese phosphate (LFMP) battery materials is performed under oxidative conditions, i.e. , in the presence of oxidants. Suitable oxidants include catalytic air, hydrogen peroxide, sodium persulfate, Mn(lll) hydroxides, oxyhydroxides and oxides, MnCh, and NCM. In some embodiments, step i) involves the addition of hydrogen peroxide to the black mass.

[0065] In some embodiments of the process, the black mass derived from lithium iron phosphate (LFP) battery materials and / or from lithium iron manganese phosphate (LFMP) battery materials has been subjected to oxidative roasting before leaching. In some embodiments, oxidative roasting comprises oxidizing the black mass at a temperature of from 500°C to 700°C while contacting it with an oxygen-containing gas to obtain an oxidized black mass. In some embodiments, oxidative roasting is preceded by heating the black mass to atemperature in the range of from 250°C to 500°C while contacting it with an inert gas and with a reductive gas generated in situ by thermal decomposition of the black mass.

[0066] In some embodiments, the process further comprises

[0067] g1) adjusting the pH of the mother liquor obtained in step g) to be in the range of from 4.0 to 5.0, and generating a further precipitate, g2) recovering the further precipitate obtained in step g1) and recycling the further precipitate into any one of steps b), c) or d).

[0068] As the further precipitate may contain substantial amounts of nickel, recycling the precipitate into any one of steps b), c) or d) increases the overall nickel yield.

[0069] In some embodiments of the process, the acidic aqueous solution comprising nickel, cobalt, manganese, and lithium ions obtained in step e) is further processed to recover nickel and / or cobalt and / or manganese, and / or lithium from the solution, e.g., using subsequent solvent extraction steps for recovering manganese cations and / or cobalt cations and / or nickel cations from the mother liquor obtained in step d) or step d2).

[0070] Separate workup of Ni-based battery materials and Fe-based battery materials requires lots of equipment, and workup of a mixed feed of Fe- and Ni-based battery materials is difficult, due to the differing chemical properties and value of the components. The process of the present disclosure combines treatment of black mass from different battery materials, e.g., NCM battery materials and LFP battery materials. The process of the present disclosure provides a cost efficient and accessible recycling method, reducing equipment required and using existing infrastructure. Separate units for leaching and, optionally, for thermal treatment, handle initial processing of Fe-based battery material, after which the leach solution obtained is combined with a leach solution from a Ni-based battery material in a specific volumetric ratio. Despite combined processing of the leach solution from Fe-based battery material and Ni-based battery material, only slight dilution of valuable metals Ni and Co occurs in theprocess stream of the Ni-based battery material. Recycling the precipitate comprising impurities into the leaching of Fe-based battery material improves total yield of Ni, Co, and Li.

[0071] A flow diagram of an embodiment of the process of the present disclosure is shown in Fig. 1.

[0072] In step 100, black mass derived from Ni-based battery materials is leached with sulfuric acid, followed by solid / liquid separation.

[0073] In step 200, copper ions are removed from the mother liquor obtained in step 100.

[0074] In step 300, a first precipitate 301 is generated by raising the pH to a value in the range of from 3 to 4, followed by solid / liquid separation. The precipitate 301 mainly comprises compounds of Al and Fe, but also some co-precipitated compounds of nickel, cobalt, and / or lithium, and is recycled into step 400.

[0075] In step 400, black mass derived from Fe-based battery materials is leached with sulfuric acid, followed by solid / liquid separation. A solid residue 401 is obtained which mainly contains graphite and FePCU. The mother liquor obtained in step 400, which comprises Cu2+and Li+, is dosed into step 100. The black mass derived from Fe-based battery materials leached in step 400 optionally is subjected to thermal treatment in step 500 before being introduced into step 400.

[0076] Optional step 500 comprises oxidative roasting, optionally preceded by pyrolysis under reducing conditions.

[0077] In step 600, a second precipitate 601 is generated from the mother liquor obtained in step 300 by raising the pH to a value in the range of from 4 to 5, followed by solid / liquid separation. The second precipitate 601, which also contains some co-precipitated nickel, is recycled into step 100.In step 700, manganese carbonate 701 is recovered from the mother liquor obtained in step 600 by solvent extraction of Mn2+, followed by precipitation of MnCOs.

[0078] In step 800, cobalt sulfate 801 is recovered from the liquid depleted of manganese obtained in step 700 by solvent extraction of Co2+.

[0079] In step 900, nickel sulfate 901 is recovered from the liquid depleted of cobalt obtained in step 800 by solvent extraction of Ni2+.

[0080] In step 1000, magnesium is removed from the liquid depleted of nickel obtained in step 900 by raising the pH to a value above 10, and precipitating magnesium salts, followed by solid / liquid separation.

[0081] In step 1100, lithium is recovered from the mother liquor obtained in step 1000, e.g., by precipitation of Li2COs or U3PO4, or by solvent extraction.

[0082] Examples

[0083] Feeds

[0084] Table 1 Composition [wt%] of the feeds used in examples 1 to 7

[0085] Feed Cu Fe Li Ni P

[0086] 1 4.20% 0.61% 3.50% 14.50% 0.67%

[0087] 2 4.50% 0.51% 3.60% 14.30% 1.00%

[0088] 3 8.60% 0.26% 3.70% 16.00% 0.45%

[0089] 4 0.31% 0.27% 0.69% 0.12% 0.019% 5 5.7% 13.7% 2.1% 0.56% 8.8%

[0090]

[0091] 100 g of a NCM battery black mass 1 was suspended in deionized water with a solids / liquid (SZL)-ratio of 0.25, heated to 95°C and then treated with H2SO4in a ratio of 0.85 by weight, relative to the solids feed. After that, the reaction mixturewas stirred for 2 h. The inert gas atmosphere was then exchanged with ambient air, which was passed through the mixture at a flow rate of 20 NL / h. After stirring for 3 h, the slurry had reached an ORP of -64 mV vs. Ag / AgCI and a pH of 0.5. Aeration was stopped and 12.2 g of SO2 were introduced into the mixture over the course of 2 h. The suspension was then filtered, and the solids were washed and dried. Filtrate a and solids i were obtained with a yield of 416 g and 31 g, respectively. A Cu-leaching efficiency of 0.0% was reached.

[0092] Example 2

[0093] 75 g of a NCM battery black mass 1 was suspended in deionized water with a S / L-ratio of 0.38, heated to 95°C and then treated with H2SO4 in a ratio of 0.88 by weight, relative to the solids feed. After that, the reaction mixture was stirred for 2 h. The inert gas atmosphere was then exchanged with ambient air, which was passed through the mixture at a flow rate of 20 NL / h and a solution containing Cu2+-ions was added in a ratio of 0.2 by weight of the Cu contained in the solids feed. After stirring for 3 h, the slurry had reached an ORP of 143 mV vs. Ag / AgCI and a pH of 1.0. The suspension was then filtered, and the solids were washed and dried. Filtrate b and solids ii were obtained with a yield of 244.5 g and 19.2 g, respectively. A Cu-leaching efficiency of 84.9% was reached.

[0094] Comparing examples 1 and 2, adding a Cu2+-containing solution enables Cu-leaching even at reaction conditions where it is typically not observed.

[0095] Example 3 (Comparative)

[0096] 75 g of a NCM battery black mass 2 was suspended in deionized water with a S / L-ratio of 0.25, heated to 95°C and then treated with H2SO4 in a ratio of 1.0 by weight, relative to the solids feed. After that, the reaction mixture was stirred for 3 h. The reaction mixture was then cooled to 85°C and the inert gas atmosphere was exchanged with ambient air, which was passed through the mixture at a flow rate of 20 NL / h. Samples were taken after 1 and 2 h and after stirring for 4 h, the slurry had reached an ORP of 404 mV vs. Ag / AgCI and a pH of 0.5. The suspension was then filtered, and the solids were washed and dried.Filtrate c and solids iii were obtained with a yield of 321.3 g and 5.1 g, respectively. A Cu-leaching efficiency of 97.9% was reached.

[0097] Example 4

[0098] 75 g of a NCM battery black mass 2 was suspended in deionized water with a S / L-ratio of 0.25, heated to 95°C and then treated with H2SO4 in a ratio of 1.0 by weight, relative to the solids feed. After that, the reaction mixture was stirred for 2 h. The reaction mixture was then cooled to 90°C, the inert gas atmosphere was exchanged with ambient air, which was passed through the mixture at a flow rate of 20 NL / h and a solution containing Cu2+-ions was added in a ratio of 0.1 by weight of the Cu contained in the solids feed. Samples were taken after 2 and 4 h and after stirring for 5 h, the slurry had reached an ORP of 404 mV vs. Ag / AgCI and a pH of 0.7. The suspension was then filtered, and the solids were washed and dried. Filtrate d and solids iv were obtained with a yield of 328.3 g and 8.1 g, respectively. A Cu-leaching efficiency of 99.2% was reached.

[0099] Fig. 2 is a graphical representation of the oxidic Cu-dissolution observed in comparative Example 3 (dashed) and Example 4 (solid), determined at different reaction times. The origin of the graph represents the start of aeration at the beginning of the oxidic leaching process. The comparison of the results obtained in Examples 3 and 4 shows that adding Cu2+-containing solution increases the dissolution speed of Cu under otherwise identical reaction conditions. Example 4 shows that Cu is quantitatively leached after 2 h.

[0100] Example 5 (comparative)

[0101] 90.8 g of a NCM battery black mass 3 was suspended in deionized water with a S / L-ratio of 0.25, heated to 90°C and treated with H2SO4 in a ratio of 1.19 by weight, relative to the solids feed. After that, the reaction mixture was stirred for 2 h. Then, the inert gas atmosphere was exchanged with ambient air, which was passed through the mixture at a flow rate of 20 NL / h. The reaction mixture was stirred for 3 h, the aeration then stopped and after stirring another 2 h, the slurry had reached an ORP of 143 mV vs. Ag / AgCI and a pH of 1.3. The suspension was filtered and the solids were washed and dried. Filtrate e andsolids v were obtained with a yield of 462.6 g and 23.7 g, respectively. A Cu-leaching efficiency of 96.7% was reached.

[0102] Example 6

[0103] LFP Leach

[0104] 75.7 g of LFP battery black mass 5 was suspended in water with a S / L-ratio of 0.2 and subsequently treated with H2SO4 in a ratio of 0.2 by weight, relative to the solids feed. After that the reaction was heated to 80 °C and stirred for 1 h. Then, a solution of 30 wt.-% H2O2 in DI water equal to 1.65 times the molar content of Fe and Cu was added to the reaction within 20 min. After stirring for another 2 h aeration with 30 NL / h was started and stirring continued for 1 h. The suspension was then filtered, and the solids were washed and dried. Filtrate f and solids vi were obtained with a yield of 347.8 g and 65.5 g, respectively.

[0105] NCM Leach

[0106] 90 g of a NCM battery black mass 3 was suspended in deionized water and 74.4 g of filtrate f with a S / L-ratio of 0.25 and a Cu2+:Cu-ratio of 0.06, heated to 90°C and treated with H2SO4 in a ratio of 1.19 by weight, relative to the solids feed. After that, the reaction mixture was stirred for 2 h. Then, the inert gas atmosphere was exchanged with ambient air, which was passed through the mixture at a flow rate of 20 NL / h. The reaction mixture was stirred for 3 h, the aeration then stopped and after stirring another 2 h, the slurry had reached an ORP of 181 mV vs. Ag / AgCI and a pH of 0.5. The suspension was then filtered, and the solids were washed and dried. Filtrate g and solids vii were obtained with a yield of 476.5 g and 27.0 g, respectively. A Cu-leaching efficiency of 96.8% was reached.

[0107] Table 2 Composition [wt%] of the filtrates obtained in Examples 1 to 6 Filtrate Cu Fe Li Ni P

[0108] a < 0.001% 0.10% 0.67% 2.80% 0.11% b 1.00% 0.12% nd 3.03% nd

[0109] c 0.90% 0.11% 0.70% 2.90% 0.12%d 1.00% 0.12% 0.65% 2.80% nd

[0110] e 1.68% 0.04% 0.64% 3.03% 0.07% f 0.58% 0.03% 0.32% 0.07% 0.05% g 1.71% 0.04% nd 3.0% nd

[0111] Table 3 Composition [wt%] of the solids obtained in Examples 1 to 6 Solids Cu Fe Li Ni P i 9.80% 0.19% 0.20% 2.60% 0.20% ii 3.00% 0.17% nd 5.60% nd

[0112] iii 1.40% 0.58% 0.44% 5.30% nd

[0113] iv 0.39% 0.27% 0.29% 2.50% nd

[0114] v 1.10% 0.010% 0.130% 0.130% 0.07% vi 3.70% 11.5% 0.09% 0.26% 7.60% vii 0.96% 0.04% 0.15% 0.17% 0.05%

[0115] Table 4 Yields [wt%] of selected elements in the filtrates of Examples 1 to 6 Example Cu Li Ni

[0116] 1 (comparative) 0.0% 90.4% 98.2%

[0117] 2 84.9% nd 100.0%

[0118] 3 (comparative) 97.9% 92.3% 99.2%

[0119] 4 99.2% 94.3% 99.1%

[0120] 5 (comparative) 96.7% 99.1% 99.8%

[0121] 6 - LFP 43.9% 96.3% 59.8%

[0122] 6 - NCM 96.8% 98.9% 99.7%

[0123] Example 7

[0124] Leaching

[0125] 135.6 g of a NCM battery black mass 3 was suspended in a mixture of 432 mL deionized water and 108 g acidic leach solution 4 from LFP black mass digestion such that the ratio of Cu2+:Cu(feed) was 0.3. The reaction mixture was then heated to 90°C and treated with H2SO4 in a ratio of 1.0 by weight, relativeto the solids feed. After that, the reaction mixture was stirred for 2 h. Then, the inert gas atmosphere was exchanged with ambient air, which was passed through the mixture at a flow rate of 20 NL / h and the reaction mixture was stirred for 3 h. The aeration was stopped and stirring was continued for 2 h under static atmosphere whereafter the slurry had reached an ORP of 137 mV vs. Ag / AgCI and a pH of 1.5. The suspension was then filtered, and the solids were washed and dried. Filtrate h and solids viii were obtained with a yield of 654.0 g and 46.0 g, respectively. A Cu-leaching efficiency of 64.7% was reached.

[0126] Cu-Separation

[0127] 614.8 g of the filtrate were heated to 85°C and Na2S2O3 was added with a molar ratio of 1.2 compared to the Cu-content of the filtrate. After stirring for 2 h the reaction mixture was filtered, and the solids washed and dried. Filtrate i and solids ix were obtained with a yield of 635.4 and 8.5 g, respectively.

[0128] 1stImpurity Precipitation

[0129] 558.0 of the filtrate were heated to 80°C, the pH was adjusted to 4 using Na2COs and aeration with a flow of 15 NL / h was started. After stirring for 4 h, the reaction mixture was filtered, and the solids washed and dried. Filtrate j and solids x were obtained with a yield of 504.9 and 43.8 g, respectively.

[0130] 2ndImpurity Precipitation

[0131] 429.0 g of the filtrate were heated to 80°C, the pH was adjusted to 5 using Na2CO3. After stirring for 2 h the reaction mixture was filtered, and the solids washed and dried. Filtrate k and solids xi were obtained with a yield of 413.5 and 3.1 g, respectively.

[0132] Example 7 shows that LFP based leach solutions can be combined into NCM leaching without impacting subsequent work up processes, when applying the parameter ranges described in this application.Table 5 Composition [wt%] of the filtrates obtained in Example 7.

[0133] Filtrate Al F Li Ni P h nd nd 0.820% 3.270% 0.086% i nd nd 0.72% 2.80% 0.08% j 0.09% 0.14% 0.52% 2.43% < 0.001% k 0.01% 0.01% 0.50% 2.22% < 0.001%

[0134] Table 6 Composition [wt%] of the solids obtained in Example 7.

[0135] Solid Al F Li Ni P Viii nd nd 0.170% 0.520% 0.100% ix nd nd 0.07% 0.27% < 0.01% X 7% 3.3% 1.60% 5.40% 0.85% xi 10.0% 14.4% 1.10% 17.50% 0.05%

[0136] Table 7 Yields [wt%] of selected elements in the filtrate of example 7 after 1stimpurity precipitation.

[0137] Example Li Ni

[0138] 7 81.2% 83.8%

Claims

BASF SE B25.131P-WO 67056 Ludwigshafen am Rhein 14.01.2026 / lg / np / jlClaims1. A process for treating black mass comprising metallic copper, comprising a) dispersing the black mass in water,b) adding an aqueous solution comprising Cu2+and SCU2' to the dispersion, such that the ratio of Cu2+:Cu° in the dispersion is in the range from 0.01:1 to 2:1,c) optionally, leaching the dispersed black mass with sulfuric acid under inert atmosphere, and subsequentlyd) leaching the dispersed black mass with sulfuric acid while injecting air into the mixture, thereby dissolving metallic copper present in the black mass and obtaining a pregnant leach solution.

2. The process of claim 1 , wherein the concentration of SCU2' in the pregnant leach solution does not exceed 250 g / l.

3. The process of claim 1 or 2, wherein the aqueous solution comprising Cu2+and SO42’ also comprises Li+.

4. The process of claim 3, wherein the concentration of Li+in the aqueous solution comprising Cu2+and SO42-is in the range of from 0.05 wt% to 2.0 wt%, relative to the total weight of the aqueous solution.

5. The process of any one of claims 1 to 4, wherein the aqueous solution comprising Cu2+and SO42-also comprises iron and phosphorus.

6. The process of claim 5, wherein the concentration of iron and phosphorus in the aqueous solution comprising Cu2+and SO42-is not more than 0.5 wt% each, relative to the total weight of the aqueous solution.

7. The process of any one of claims 3 to 6, wherein the aqueous solution comprising Cu2+and SCU2' has been obtained by leaching black mass derived from lithium iron phosphate (LFP) battery materials and / or lithium iron manganese phosphate (LFMP) battery materials with sulfuric acid under oxidative conditions.

8. The process for treating black mass comprising metallic copper according to claim 1, wherein the black mass is derived from lithium ion battery materials comprising nickel and / or cobalt and / or manganese, the process comprisinga) dispersing the black mass in water,b) adding an acidic aqueous solution comprising copper(ll) cations and lithium cations obtained in step i) to the dispersion, c) optionally, leaching the dispersed black mass with sulfuric acid under inert atmosphere, and subsequentlyd) leaching the black mass with sulfuric acid while injecting air into the mixture and,e) separating solids from the mixture to obtain an aqueous acidic solution comprising lithium cations and copper cations, as well as nickel cations and / or cobalt cations and / or manganese cations, f) removing copper cations from the aqueous acidic solution, g) adjusting the pH of the aqueous acidic solution depleted of copper cations obtained in step f) to be in the range of from 3.0 to 4.0, and generating a precipitate,h) recovering the precipitate obtained in step g) and optionally recycling the precipitate into step i),i) leaching black mass derived from lithium iron phosphate battery materials and / or lithium iron manganese phosphate battery materials with sulfuric acid, optionally under oxidative conditions, to obtain an acidic aqueous solution comprising copper(ll) cations and lithium cations.

9. The process of claim 8, wherein step i) involves the addition of hydrogen peroxide to the black mass.

10. The process of claim 8 or 9, wherein in step f) copper cations are removed from the aqueous acidic solution by solvent extraction, after the pH of the solution obtained in step b) has been adjusted to be in the range of from 1.5 to 2.5.

11. The process of claim 8 or 9, wherein in step f) copper cations are removed from the aqueous acidic solution by precipitating copper sulfide and subsequently separating the precipitate from the aqueous acidic solution.

12. The process of any one of claims 8 to 11 , further comprisingg1) adjusting the pH of the mother liquor obtained in step g) to be in the range of from 4.0 to 5.0, and generating a further precipitate, g2) recovering the further precipitate obtained in step g1) and recycling the further precipitate into any one of steps b), c) or d).

13. The process of claim 12, further comprising subsequent solvent extraction and / or precipitation steps for recovering manganese cations and / or cobalt cations and / or nickel cations from the mother liquor obtained in step g2).

14. The process of any one of claims 8 to 13, wherein the black mass derived from lithium iron phosphate battery materials and / or lithium iron manganese phosphate battery materials has been subjected to oxidative roasting before leaching.

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