Recycling electronic waste to recover lithium

Abstract

The invention discloses a method for recovering metal from electronic waste or leach residue thereof, the electronic waste or leach residue comprising copper element and one or more lithium compounds, the method comprising: leaching the electronic waste or leach residue with a leaching solution comprising ammonium sulfate in the presence of an oxidizing agent, a leaching solution containing copper ions and lithium ions and solid residues are provided; and separating the leachate and the solid residue.

Description

Technical Field

[0001] The present invention generally relates to a process for recovering lithium and optionally other transition metals from waste electronic material comprising at least copper and one or more lithium salts, in particular, wherein the waste electronic material is waste lithium-ion batteries. Background Art

[0002] The amount of used electronics, especially rechargeable lithium-ion batteries, used worldwide has been growing rapidly in recent years and is set to expand further with the development of emerging markets such as electric vehicles and large-scale power storage. As demand for electronic devices, especially those using lithium-ion batteries, increases, so does the demand for the metal / metal oxide components used in these devices. The rapidly growing demand for some of these metals, such as cobalt, has put pressure on the sustainable supply of these resources. This has led to a rapid increase in the cost of these metals.

[0003] There has been little interest in developing processes to recover and recycle the various components and parts of modern electronic devices, such as batteries. In the case of batteries, this is primarily due to the relatively small number of lithium-ion batteries available for recycling and the relatively high cost of traditional pyrometallurgical and hydrometallurgical processes to achieve recycling. As the demand for lithium-ion batteries continues to increase, the number of spent lithium-ion batteries available for recycling is also increasing. Low-cost, efficient recycling processes are needed, especially for more complex metal / metal oxide components. Although the following discussion focuses on lithium-ion batteries, it is applicable to a range of electronic devices as these also contain a range of different metal compounds.

[0004] The composition of lithium-ion batteries has changed significantly in recent years. While some battery recycling processes have been developed, these are primarily limited to recovering certain specific metals from certain types of batteries or feedstocks. For example, the vast majority of early batteries were lithium-cobalt batteries, and recycling methods focused on recovering cobalt. As demand for lithium increased, recycling methods shifted to recovering both cobalt and lithium. As battery technology further developed, other metals were added to the cathode, such as manganese, nickel, aluminum, iron, and phosphorus. Methods for recovering lithium and cobalt are not suitable for recovering other metals, nor for different battery chemistries.

[0005] As the use of lithium-ion batteries increases, the amount of used lithium-ion batteries that can be recycled will also increase. However, the supply of used lithium-ion batteries will contain many different types of batteries. Recycling methods that only work for a single battery type pose significant problems for the commercialization of such processes. Specifically, such methods require one or more sorting steps and pre-treatment steps. Given this, it is necessary to develop a process that can recover a variety of metals from a range of different lithium-ion battery types.

[0006] Most battery recycling processes developed involve the dissolution of the metal components in an acidic medium. This is a non-selective leaching process during which most of the metals contained in the battery are dissolved. Batteries contain large amounts of a variety of cheap metals such as iron, manganese and aluminum. Some batteries may also contain phosphorus. If these cheap metals and phosphorus are not removed before leaching, the acid consumption is high. Therefore, pre-treatment processes are required to separate iron and aluminum from valuable metal components such as cobalt, nickel, copper and lithium. In doing so, the recovery of these valuable metals is reduced because the separation achieved in these pre-treatment processes is not 100% effective.

[0007] It would be desirable to provide a method for recovering metals, particularly lithium, from discarded electronic devices, such as batteries having a wide range of chemistries.

[0008] It is an object of the present invention to address one or more disadvantages of the prior art and / or to provide a useful alternative. Summary of the invention

[0009] In one aspect of the present invention, there is provided a method for recovering metals from electronic waste or leached residues thereof, wherein the electronic waste or leached residues contain copper and one or more lithium compounds, the method comprising:

[0010] Leaching the electronic waste or leach residue with a leaching solution comprising ammonium sulfate in the presence of an oxidant to provide a leachate comprising copper ions and lithium ions and a solid residue; and

[0011] The leachate and the solid residue are separated.

[0012] The element copper refers to the copper metal.

[0013] In one embodiment, the electronic waste consists of or consists essentially of one or more types of lithium ion batteries (preferably in the form of lithium ion battery fragments). In an alternative embodiment, the electronic waste comprises a mixture of one or more types of lithium ion batteries and other electronic waste such as printed circuit boards.

[0014] In one embodiment, the one or more lithium compounds include lithium metal oxides and / or lithium metal phosphates, such as in the form of LiMO2, LiMPO4, wherein M is one or more metals selected from the group consisting of aluminum, cobalt, manganese and / or nickel. In a preferred form, the one or more lithium metal compounds include LiNi w Co x Al y Mn z O2, where w+x+y+z=1, and / or LiNi x Mn y Co 1-x-yO2, where 0≤x+y≤1, and / or LiNi x Co y Al z O2, where x+y+z=1, and / or LiFePO4.

[0015] In one embodiment, the copper ions and lithium ions are in the form of CuSO4 and Li2SO4, respectively.

[0016] In one embodiment, the copper element is present in an amount sufficient to provide a redox potential of -100 mV or less, the redox potential being determined using an Ag / AgCl reference electrode. Preferably, the redox potential is -150 mV or less. The inventors have found that a redox potential of -100 mV or less is useful for ensuring the dissolution of lithium ions and the reduction of transition metals in electronic waste. In particular, the inventors have found that a redox potential of -100 mV or less is important for the formation of soluble manganese ions. If the redox potential is higher than -100 mV, manganese will increasingly appear in the solid residue.

[0017] In one embodiment, the oxidant is present in an amount sufficient to provide a redox potential of +50 mV or higher, as measured using an Ag / AgCl reference electrode. Preferably, the redox potential is +100 mV or higher, more preferably, the redox potential is +150 mV or higher.

[0018] In one embodiment, the copper element is present in an amount of at least 4 wt% relative to the total weight of the electronic waste. Preferably, the copper element is present in an amount of at least 5 wt% relative to the total weight of the electronic waste. More preferably, the copper element is present in an amount of at least 6 wt% relative to the total weight of the electronic waste. Even more preferably, the copper element is present in an amount of at least 7 wt% relative to the total weight of the electronic waste. Most preferably, the copper element is present in an amount of at least 8 wt% relative to the total weight of the electronic waste.

[0019] In one embodiment, the oxidant comprises, consists of or consists essentially of a solid oxidant. More preferably, the oxidant is present in the electronic waste in the form of a metal oxide, in particular an oxide of cobalt, manganese or nickel. In some embodiments, the oxidant is a component of one or more lithium compounds, such as a cobalt, manganese and / or nickel component of a lithium metal oxide.

[0020] The inventors have found that the leaching step promotes redox reactions between the copper element and the cobalt, manganese and nickel salts, which facilitates the formation of soluble salts of cobalt, copper, manganese and nickel ions.

[0021] In embodiments where nickel is present, preferably the ratio of copper:nickel is 0.5:1 or greater, such as up to about 2:1.

[0022] In embodiments where cobalt is present, preferably the ratio of copper:cobalt is 0.5:1 or greater, such as up to about 2:1.

[0023] In embodiments where manganese is present, preferably the ratio of copper:cobalt is 0.5:1 or greater, such as up to about 2:1.

[0024] In embodiments where nickel and / or cobalt and / or manganese are all present, preferably the ratio of copper:(nickel+cobalt+manganese) is 0.5:1 or greater, such as up to about 2:1.

[0025] In one embodiment, the temperature is from about 0°C to a temperature up to or below the boiling point of the leaching solution under leaching operating conditions, for example below 100°C. Preferably, the temperature starts from about 40°C. Preferably, the temperature is up to about 60°C.

[0026] In one embodiment, the leaching is performed at atmospheric pressure.

[0027] In one embodiment, the leaching is performed for up to 24 hours. Preferably, the leaching is performed for up to 18 hours. More preferably, the leaching is performed for up to 12 hours. Most preferably, the leaching is performed for up to 8 hours. Additionally or alternatively, the leaching is performed for at least 0.5 hours. Preferably, the leaching is performed for at least 1 hour. More preferably, the leaching is performed for at least 1.5 hours. Most preferably, the leaching is performed for at least 2 hours.

[0028] In one embodiment, the method further comprises recovering copper ions from the leachate. Preferably, the copper ions are recovered using a solvent extraction process, the solvent extraction process comprising contacting the leachate with an extractant so that the copper ions are adsorbed into the extractant to form a copper-loaded extractant, and separating the copper-loaded extractant from the leachate. More preferably, the method further comprises stripping the copper ions from the copper-loaded extractant using a stripping agent such as sulfuric acid.

[0029] In one form of the above embodiment, after the step of recovering copper ions from the leachate, the method further comprises:

[0030] crystallizing lithium ammonium sulfate from the leachate, and

[0031] The crystallized lithium ammonium sulfate is thermally decomposed to form a gas comprising ammonia and sulfur oxides and solid lithium sulfate.

[0032] Preferably, before the step of crystallizing lithium ammonium sulfate, the leachate is treated so that the leachate is depleted in ammonia, copper, nickel, cobalt or manganese, and / or the leachate is substantially free of ammonia, aluminum, copper, iron, nickel, cobalt or manganese.

[0033] Preferably, before the step of crystallizing lithium ammonium sulfate, the leachate contains ammonia, copper, nickel, cobalt, manganese, each at a concentration of 100 mg / L or less. Preferably, the concentration of each is 80 mg / L or less. Most preferably, the concentration of each is 60 mg / L or less.

[0034] In one embodiment, the electronic waste further comprises one or more transition metal salts, more preferably, transition metal oxides. In this case, it is further preferred that the oxidant is one or more transition metal salts or oxides, and the leachate comprises one or more transition metal ions.

[0035] In one form of the above embodiment, the one or more transition metal salts are components of a lithium metal oxide and / or a lithium metal phosphate.

[0036] In one form of the above embodiment, the one or more transition metals are selected from the group consisting of cobalt, manganese and / or nickel.

[0037] In the case where the electronic waste further comprises one or more transition metal salts, it is further preferred that the leaching is an alkaline leaching and the leaching solution comprises a sufficient amount of ammonia to make the pH between about 8.5 and about 10.5. More preferably, the leaching solution further comprises ammonium chloride. Preferably, the ammonium chloride is present in a concentration of at least 1 g / L.

[0038] In one embodiment, the leaching is alkaline leaching.

[0039] In one form of the above embodiment, the leach solution further comprises ammonia and / or ammonium chloride. Preferably, the amount of ammonia is sufficient to provide a pH of the leach solution of about 8.5 to about 10.5. Preferably, the ammonium chloride is present at a concentration of at least 1 g / L.

[0040] In one embodiment, the electronic waste further comprises one or more nickel salts, preferably in the form of nickel oxides, and the leaching solution further comprises ammonia in an amount such that the pH of the leaching solution is from about 8.5 to about 10.5, and wherein the leachate comprises at least copper ions, lithium ions and nickel ions. Preferably, the pH starts at about 9. More preferably, the pH is up to about 10.

[0041] In one form of the above embodiment, the leach solution comprises ammonia and ammonium sulfate in a ratio of about 1:2 to about 1:20.

[0042] In one version of the above embodiment, the ratio of copper:nickel is from about 2:1 to about 0.5:1.

[0043] In one form of the above embodiment, the method further comprises recovering copper and nickel from the leachate simultaneously via a solvent extraction process. Preferably, the solvent extraction process comprises contacting the leachate with an extractant so that copper ions and nickel ions are adsorbed into the extractant to form an extractant loaded with copper and nickel, and separating the extractant loaded with copper and nickel from the leachate. More preferably, the method further comprises stripping copper ions and nickel ions from the extractant loaded with copper and nickel using a stripping agent (such as sulfuric acid), wherein nickel ions are selectively recovered at a first stripping agent concentration, and then copper ions are recovered at a second stripping agent concentration, and the first stripping agent concentration is less than the second stripping agent concentration.

[0044] In one embodiment, the electronic waste further comprises cobalt, and the leaching solution further comprises ammonia in an amount such that the pH of the leaching solution is from about 8.5 to about 10.5, and wherein the leachate comprises at least copper ions, lithium ions, and cobalt ions.

[0045] In one version of the above embodiment, the ratio of copper:cobalt is from about 2:1 to about 0.5:1.

[0046] In one form of the above embodiment, the method further comprises recovering copper ions from the leachate and precipitating cobalt from the leachate after removing the copper ions.

[0047] Preferably, the step of precipitating cobalt from the leachate includes precipitating cobalt sulfide from the leachate. In an embodiment where nickel and / or manganese are present in the electronic waste, the step of precipitating cobalt from the leachate is performed after recovering manganese and / or nickel. That is, preferably, before the step of precipitating cobalt, the leachate is substantially free of copper, manganese and nickel. For example, the leachate contains copper and / or manganese and / or nickel, each at a concentration of 100 mg / L or less. More preferably, each at a concentration of 80 mg / L or less. Most preferably, each at a concentration of 60 mg / L or less. This is to minimize the co-precipitation of copper, manganese and nickel sulfides, thereby providing a cobalt product of higher purity.

[0048] In one embodiment, the electronic waste further comprises manganese, and the leaching solution further comprises a leachate containing manganese, and the method further comprises:

[0049] treating the leachate with an oxidizing agent to form a precipitate of manganese and to provide a manganese-depleted leachate comprising copper ions and lithium ions: and

[0050] The manganese precipitate is separated from the manganese-depleted leachate.

[0051] In one form of the above embodiment, the oxidant is air.

[0052] In one version of the above embodiment, the ratio of copper:manganese is from about 2:1 to about 0.5:1.

[0053] In one embodiment, the electronic waste further comprises iron and aluminum, the solid residue comprises iron and aluminum, and the leachate is an iron-depleted, aluminum-depleted leachate, and / or the leachate contains substantially no iron or aluminum.

[0054] In one embodiment, the leachate comprises iron and aluminum at a concentration of 100 mg / L or less, respectively. More preferably, the concentration is 80 mg / L or less, respectively. Most preferably, the concentration is 60 mg / L or less, respectively.

[0055] In one embodiment, the electronic waste contains copper element and one or more compounds of cobalt, lithium and nickel, wherein the leaching solution further contains ammonia, and the leachate contains cobalt ions, copper ions, lithium ions and nickel ions; after the step of separating the solid residue from the leachate, the method further comprises:

[0056] subjecting the leachate to a solvent extraction step to remove copper ions and nickel ions from the leachate and form a copper-depleted, nickel-depleted leachate;

[0057] subjecting the copper-depleted, nickel-depleted leachate to a precipitation step to remove cobalt ions from the copper-depleted, nickel-depleted leachate and form a cobalt-depleted, copper-depleted, nickel-depleted leachate; and

[0058] Recovering lithium from the cobalt-depleted, copper-depleted and nickel-depleted leaching solutions,

[0059] Before the step of recovering lithium, the leaching solution is subjected to an ammonia recovery step, so that during the process of recovering lithium, the cobalt-depleted, copper-depleted and nickel-depleted leaching solution is substantially free of ammonia.

[0060] In one form of the above embodiment, the cobalt ions comprise Co 2+ ions, and before subjecting the leachate to a solvent extraction step, the method further comprises treating the leachate with an oxidizing agent to remove the Co 2+ Ion oxidation to Co 3+ ion.

[0061] In one embodiment, the electronic waste contains copper and one or more compounds of cobalt, lithium, manganese and nickel, wherein the leaching solution further contains ammonia, and the leachate contains cobalt ions, copper ions, lithium ions, manganese ions and nickel ions; after the step of separating the solid residue from the leachate, the method further comprises:

[0062] The leachate is treated with an oxidizing agent to form a manganese precipitate and provide a manganese-depleted leachate comprising 3+ Cobalt, copper, lithium and nickel in ionic form; and

[0063] separating the manganese precipitate from the manganese-depleted leachate;

[0064] subjecting the manganese-depleted leachate to a solvent extraction step to remove copper ions and nickel ions from the manganese-depleted leachate and form a copper-depleted, manganese-depleted, nickel-depleted leachate;

[0065] subjecting the copper-depleted, manganese-depleted, nickel-depleted leachate to a precipitation step to remove cobalt ions from the copper-depleted, manganese-depleted, nickel-depleted leachate to form a cobalt-depleted, copper-depleted, manganese-depleted, nickel-depleted leachate; and

[0066] Recovering lithium from the cobalt-depleted, copper-depleted, manganese-depleted, and nickel-depleted leaching solutions;

[0067] Before the step of recovering lithium, the leaching solution is subjected to an ammonia recovery step, so that during the process of recovering lithium, the cobalt-depleted, copper-depleted and nickel-depleted leaching solution is substantially free of ammonia.

[0068] In one embodiment, the leachate solution further comprises ammonia, the leachate is a first leachate, the solid residue is a first solid residue, and after the step of separating the first leachate from the first solid residue, the method further comprises:

[0069] leaching the solid residue with a second leach solution comprising ammonium sulfate to provide a second leachate and a second solid residue; and

[0070] separating the second leachate from the second solid residue;

[0071] leaching the second solid residue with an acid to provide a third leachate and a third solid residue;

[0072] separating the third leachate from the third solid residue; and

[0073] The first leachate, the second leachate and the third leachate are combined to form a combined leachate.

[0074] In one form of the above embodiment, the electronic waste contains copper and one or more compounds of cobalt, lithium, manganese and nickel, and the method includes recovering one or more of cobalt, copper, lithium, manganese and nickel from the combined leachate.

[0075] In one embodiment, the leach solution is substantially free of acid, and / or contains no added acid species. In some cases, the natural pH of the leach solution during the leaching process is less than 7. In this case, this is due to acid species generated during the leaching process. Therefore, in a preferred form of the invention, any acid present in the leach solution is generated during the leaching process of the electronic waste.

[0076] In one embodiment, the leaching solution is substantially free of organic compounds. For example, the leaching solution is free of monomers, oligomers, polymers, surfactants, organic leaching agents, organic acids, organometallic compounds, and the like.

[0077] In one embodiment, the leach solution is substantially free of biological material. For example, the leach solution is free of vegetable, fruit, or animal biological matter.

[0078] In one embodiment, the method includes: performing a first leaching on the electronic waste with a first leaching solution to provide a first leachate and a solid residue, and leaching the leached residue with a leaching solution containing ammonium sulfate in the presence of an oxidant to provide a leachate containing copper ions and lithium ions and a solid residue.

[0079] It will be appreciated by those skilled in the art that there may be additional leaching steps between the first leaching and the step of leaching the leached residue. For example, a second leaching may be performed with a second leaching solution to produce a second leachate and a second leached residue, and the step of leaching the leached residue is one of the steps of leaching the second leached residue.

[0080] The first leaching (and the second leaching in various embodiments) can be, for example, an acid leaching, an alkaline leaching, etc. However, it is preferred that the first and / or second leaching solutions contain one or more of ammonia, ammonium sulfate and ammonium chloride. In embodiments thereof, the first and / or second leaching solutions contain, consist of, consist essentially of or consist of: (1) ammonia and ammonium chloride, (2) ammonia and ammonium sulfate, (3) ammonium sulfate and ammonium chloride, and (4) ammonia, ammonium chloride and ammonium sulfate. In embodiments, the leachate is combined with the first leachate (and the second leachate in embodiments including a second leaching step) to form a combined leachate, from which copper and lithium, as well as cobalt, manganese and nickel (if present) can be recovered according to the above method.

[0081] The reference to any prior art in this specification is not an acknowledgement or representation that the prior art forms part of the common general knowledge in any jurisdiction, or that a person skilled in the art could reasonably expect that the prior art would be understood, regarded as relevant and / or could be combined with other prior art.

[0082] As used herein, unless the context requires otherwise, the use of the term "comprise" and variations of the term, such as "comprising", "comprises" and "comprised", are not intended to exclude additional additives, components, integers or steps.

[0083] BRIEF DESCRIPTION OF THE DRAWINGS

[0084] Further aspects of the invention and further embodiments of the aspects described in the preceding paragraphs will become apparent from the following description, which is given by way of example and with reference to the accompanying drawings.

[0085] Figure 1 A process flow diagram of a method according to one embodiment of the present invention is shown.

[0086] Figure 2 A process flow chart of a method according to another embodiment of the present invention is shown. DETAILED DESCRIPTION

[0087] The present invention generally relates to a method for recovering precious metals, particularly lithium, from electronic waste containing the element copper and one or more lithium-containing salts.

[0088] The method comprises leaching the electronic waste with ammonium sulfate, during which the copper element is oxidized to copper ions, thereby providing an electron source to act as a reducing agent and thereby generating soluble lithium ions from lithium-containing salts. If transition metals such as cobalt, manganese and nickel are present in the electronic waste, for example as components of lithium-containing salts or as metal oxides, these are also reduced to water-soluble ions. Various soluble metal ions, especially lithium, can be selectively recovered as products. The ammonium sulfate can also be recovered and reused for further leaching.

[0089] The method is particularly suitable for recovering lithium from spent lithium-ion batteries, in particular battery fragments (whether a single type of battery or a mixture of battery fragments from different lithium-ion batteries). The method can be advantageously used for galvanic battery fragments, that is, battery fragments that have not been subjected to pretreatment such as copper stripping and / or calcination (as opposed to black matter). As non-limiting examples, the method can be applied to extract ions of cobalt, copper, lithium, manganese and nickel, depending on the chemical composition of the battery or battery mixture in the battery fragment.

[0090] In a preferred form of the invention, the electronic waste comprises lithium ion batteries comprising lithium metal oxides or lithium metal phosphates, non-limiting disclosed examples of which include nickel manganese cobalt (NMC), lithium cobalt oxide (LCO) and lithium ion manganese oxide (LMO), lithium iron phosphate (LFP) and lithium nickel cobalt aluminum oxide (NCA) batteries and mixtures thereof. Typically, in these batteries, the lithium element is in one or more forms of LiMO2, LiMPO4 (where M is a transition metal) and / or LiNi x Co y Al z The electronic waste may further include other electronic wastes, such as printed circuit boards, etc.

[0091] Without wishing to be bound by theory, the inventors believe that the ammonium sulfate leaching promotes the oxidation-reduction of copper, which ultimately provides an electron source and soluble copper salts, and, in the process, reduces lithium metal salts (such as those described above) to release lithium ions into solution, and optionally releases copper, cobalt, manganese and nickel ions, depending on the chemical composition of the lithium ion batteries in the battery fragments. The leaching is selective because low-value metals such as iron and aluminum that may be present in the electronic waste are substantially retained in the solid residue together with low-value phosphate compounds.

[0092] In more detail, during the ammonium sulfate leaching process, copper metal is oxidized to Cu (I). The Cu (I) is in turn oxidized to Cu (II) via a redox reaction with a lithium metal salt or other transition metal salt, thereby forming soluble ions of lithium and / or cobalt, manganese and nickel (if present). In the absence of a copper metal source as a reducing agent, or a balanced lithium metal salt and / or other transition metal salt as an oxidant to convert Cu (I) to Cu (II), the redox reaction will stop. Typically, the method provides enough oxidant (in the form of a lithium metal salt and / or other transition metal salt) and enough copper to allow the reaction to proceed to the end. If the oxidant in the form of a lithium metal salt and / or other transition metal salt is insufficient, additional oxidants such as air, hydrogen peroxide, hypochlorite, etc. may be added.

[0093] The inventors have also found that it is useful to introduce ammonium chloride during the leaching process or as a component of the leaching solution as this improves the stability of the Cu(I) ions in solution, thereby making the leaching more effective and efficient.

[0094] The resulting leachate typically contains at least copper and lithium ions and, depending on the composition of the electronic waste, may additionally contain cobalt, manganese and nickel ions. When present, the cobalt, manganese and nickel ions may be selectively recovered according to the method of the present invention.

[0095] In the case where the leachate contains copper ions and lithium ions, the copper ions can be recovered via a solvent extraction process. That is, the leachate is contacted with an extractant to recover the copper ions from the leachate and form a copper-loaded extractant. The extractant can then be stripped with a stripping agent (such as sulfuric acid) to recover copper, such as in the form of a copper sulfate solution.

[0096] The substantially copper-free leachate may be further processed to recover ammonium sulfate and lithium. The inventors have discovered that lithium ammonium sulfate may be crystallized from the leachate, for example, by concentrating the leachate, for example, by evaporating water from the leachate to crystallize lithium ammonium sulfate. The lithium ammonium sulfate may then be recovered by a solid-liquid separation process (e.g., filtration, centrifugation, etc.), and then thermally decomposed into lithium sulfate crystals, ammonia, and sulfur trioxide gas. The sulfur trioxide gas may react with ammonia and water to regenerate ammonium sulfate.

[0097] If other transition metal ions are present in the leachate, such as cobalt, manganese and nickel ions, these ions may be selectively recovered prior to lithium recovery. In embodiments where cobalt, manganese and nickel are present, it is preferred to recover manganese and then cobalt from the leachate prior to copper and nickel recovery.

[0098] In the embodiment where manganese is present, manganese ions can be recovered by oxidizing manganese to manganese oxides such as Mn2O3, Mn3O4 and / or MnO2 (but not MnO), and a suitable oxidant is air. If Co(II) ions are present in the oxidation process, these ions will be oxidized to Co(III) ions. In order to prevent CoO precipitation, in addition to oxidizing Co(II) ions to Co(III) ions, the manganese recovery step is preferably carried out in the presence of ammonia, because as mentioned above, ammonia forms a stable soluble sulfate complex with cobalt ions, thereby alleviating the CoO precipitation in the oxidation treatment step. Cobalt ions can then be recovered by precipitation with various salts (e.g., carbonates and / or sulfides).

[0099] In embodiments including nickel and / or cobalt, the inventors have also discovered that introducing ammonia during the leaching process or as a component of the leach solution is useful because ammonia forms complexes with nickel and / or cobalt to form stable soluble nickel and / or cobalt ammonia sulfates, particularly in the pH range of 9 to 10. This facilitates the selective extraction and recovery of nickel and / or cobalt.

[0100] In embodiments where the leachate contains both nickel ions and cobalt ions, preferably, copper ions and nickel ions are extracted from the leachate simultaneously, followed by recovery of cobalt ions and then recovery of lithium ions. However, those skilled in the art will appreciate that these metal ions may be extracted or otherwise recovered from the leachate in a different order, and / or other metal ions may be recovered from the leachate at an intermediate stage prior to lithium recovery or possibly after lithium recovery.

[0101] Nickel ions and copper ions can be extracted simultaneously by solvent extraction. In order to promote this, the method can include an upstream oxidation step in which the cobalt ions are oxidized to Co (III). This prevents the recovery of cobalt during solvent extraction, thereby avoiding the poisoning of the extractant by Co (II) ions. Then, before the copper ions are stripped, the nickel ions can be selectively stripped from the extractant with a stripping agent. Preferably, the extractant is sulfuric acid, in which case the nickel ions can be stripped at a relatively lower sulfuric acid concentration than the copper ions, thereby allowing the selective recovery of nickel and copper ions. Cobalt can be subsequently recovered from the leachate via precipitation (e.g., precipitation with sulfides).

[0102] If present, ammonia may be recovered prior to recovery of the lithium. The ammonia may be in the form of steam stripped from the leachate.

[0103] If ammonium chloride is present, it will remain in the leachate and can be recovered (in the form of lithium ammonium sulfate as described above) after lithium is recovered from the leachate.

[0104] The present invention will be described below in conjunction with the embodiments of the present invention, which are illustrative in nature and should not be construed as limiting.

[0105] Implementation Method 1

[0106] This embodiment describes a method for recovering metals from a feed containing electronic waste, the electronic waste comprising one or more types of lithium-ion batteries. In this embodiment, the feed comprises copper metal and metal oxides of at least cobalt, lithium and nickel.

[0107] The method comprises an initial leaching step in which lithium ion battery waste (which may be mixed with other electronic waste sources) is subjected to alkaline leaching with a first leaching solution comprising ammonium sulfate. In this embodiment, the first leaching solution also comprises ammonia and ammonium chloride, both of which have been found to enhance the leaching process. Ammonia contributes to the formation of stable soluble complexes of nickel and cobalt, and ammonium chloride contributes to the stability of Cu(I), thereby increasing the effectiveness of the leaching. The leaching is carried out at atmospheric pressure and ambient temperature. However, the leaching can be carried out at an elevated temperature, for example, at a temperature below the boiling point of the leaching solution.

[0108] The alkaline leaching oxidizes the copper element contained in the lithium-ion battery into soluble copper ions, which in turn provides a source of electrons to reduce or otherwise release the cobalt, lithium and nickel ions contained in the battery. Therefore, the leaching results in the formation of a leachate and a solid residue containing soluble ions of copper, cobalt, lithium and nickel. The inventors have found that a large portion of the cobalt, nickel, copper and lithium contained is leached into the solution, for example, greater than about 90% of the nickel, copper and cobalt, and greater than about 70% of the lithium. Similarly, most of the aluminum and iron contained in the battery are retained in the solid residue, for example, greater than about 99% of the aluminum and iron.

[0109] The leachate may be subjected to a solvent extraction step to extract copper and / or nickel. The copper and / or nickel loaded solvent may then be separated from the combined leachate, followed by recovery of copper and / or nickel from the solvent. Copper and nickel may be recovered from the solvent via stripping with a stripping agent such as sulfuric acid. Typically, nickel may be selectively stripped with a lower residual acid concentration than copper, for example in a pH range of about 1 to 4, followed by stripping of copper by increasing the acid concentration, for example to greater than about 50 g / L H2SO4. This two-stage stripping may allow for selective recovery of copper and nickel in separate streams.

[0110] The leachate may then be further processed to recover the cobalt. In this embodiment, the cobalt is recovered via a cobalt precipitation process, wherein the leachate is treated with a sulfide, such as hydrogen sulfide or ammonium sulfide, to precipitate cobalt sulfide. The cobalt sulfide may then be recovered from the combined leachate using any solid-liquid separation method known to those skilled in the art, such as filtration.

[0111] The leachate, now substantially depleted of cobalt, copper and nickel, can be further processed to recover ammonia, ammonium salts and lithium.

[0112] Ammonia is stripped from the leachate and the recovered ammonia is recycled and reused as part of the first leach solution. The lithium in the leachate is typically in the form of lithium sulfate. The lithium sulfate can be crystallized with ammonium sulfate (e.g., via an evaporation process) in the form of lithium ammonium sulfate and separated from the leachate. The lithium ammonium sulfate can then be thermally treated to decompose the lithium ammonium sulfate into lithium sulfate solid, ammonia gas, and sulfur trioxide gas. The ammonia and sulfur trioxide gas can be captured and reacted with water (e.g., in a wet scrubber) to form ammonium sulfate, which can be recycled to the first and / or second leaching steps.

[0113] Implementation Method 2

[0114] This embodiment describes a method for recovering metals from a lithium-ion battery feed containing one or more types of metals. In this particular embodiment, the feed contains copper metal and metal oxides of at least lithium and nickel.

[0115] The method comprises an initial leaching step in which lithium ion battery waste (possibly mixed with other electronic waste sources) is subjected to alkaline leaching with a first leaching solution comprising ammonium sulfate. In this particular embodiment, the first leaching solution also comprises ammonia, which has been found to enhance the leaching process by promoting the formation of stable soluble nickel and cobalt complexes. The leaching is carried out at atmospheric pressure and ambient temperature. However, the leaching can be carried out at an elevated temperature, for example, at a temperature below the boiling point of the leaching solution.

[0116] The alkaline leaching oxidizes the copper element contained in the lithium ion battery into soluble copper ions, thereby providing an electron source to reduce or otherwise release the nickel and lithium ions contained in the battery. Therefore, the leaching results in the formation of a first leachate containing soluble ions of copper, lithium and nickel and a first solid residue.

[0117] Then, the first leachate is separated from the first solid residue.

[0118] The first solid residue comprises low value materials such as iron and aluminum, but depending on the type of lithium ion battery waste, the solid residue may also comprise residual lithium and nickel compounds.

[0119] The amount of lithium and nickel may be sufficient to warrant further processing to recover these metals. If so, the first solid residue may be subjected to a further leaching step with a second leaching solution comprising ammonium sulfate and preferably ammonium chloride. The inventors have found that ammonium chloride advantageously stabilizes Cu(I) ions. The second leaching is carried out at atmospheric pressure and ambient temperature. However, as described above, the second leaching can be carried out at an elevated temperature, for example at a temperature below the boiling point of the leaching solution. The second leaching can be an oxidative leaching. That is, an oxidant such as air, hydrogen peroxide, hypochlorite, etc. can be used during the leaching process to assist in the recovery of the metals. If the redox half-cell potential is below 100mV, as is the case with typical LFP battery waste feed, then the oxidant assists or enhances the leaching process.

[0120] The second leaching provides a second leachate comprising soluble ions of lithium and nickel and a second solid residue.

[0121] Then, the second leachate is separated from the second solid residue.

[0122] The first and second leachates are then combined to form a combined leachate, which can then be subjected to a number of steps to selectively recover copper, lithium and nickel.

[0123] The combined leachate may be subjected to a solvent extraction step to extract copper and / or nickel. In an alternative embodiment where the leachate comprises manganese ions, the leachate is first treated to remove manganese, for example via an oxidation and precipitation process as described above. In addition, in an embodiment where the leachate comprises cobalt ions, the leachate is first subjected to an oxidation process (e.g., during manganese recovery) to convert the cobalt ions into Co(III), thereby preventing poisoning of the extractant solvent by the cobalt ions. In any case, the copper and / or nickel loaded solvent may then be separated from the combined leachate, followed by recovery of copper and / or nickel from the solvent. Copper and nickel may be recovered from the solvent via stripping with a stripping agent such as sulfuric acid. Typically, nickel may be selectively extracted with a lower residual acid concentration than copper, for example, in a pH range of about 1 to 4, followed by stripping of copper by increasing the acid concentration, for example, to greater than about 50 g / L H2SO4. This two-stage stripping allows for selective separation of copper and nickel.

[0124] The combined leachate, now substantially depleted of copper and nickel, may be further processed to recover ammonia, ammonium salts and lithium.

[0125] Ammonia is stripped from the leachate and the recovered ammonia is recycled and reused as part of the first leach solution. The lithium in the leachate is typically in the form of lithium sulfate. The lithium sulfate can be crystallized with ammonium sulfate (e.g., via an evaporation process) in the form of lithium ammonium sulfate and separated from the leachate. The lithium ammonium sulfate can then be thermally treated to decompose the lithium ammonium sulfate into lithium sulfate solid, ammonia gas, and sulfur trioxide gas. The ammonia and sulfur trioxide gas can be captured and reacted with water (e.g., in a wet scrubber) to form ammonium sulfate, which can be recycled to the first and / or second leaching steps.

[0126] Figure 1 A process flow chart of the method according to the above embodiment is shown. Figure 1 The method of describes the recovery of copper product 18 and lithium product 30. In this embodiment, the feed stream 1 is subjected to a pretreatment process, such as crushing 100, to make the feed stream 1 suitable for further processing, which is typically <5 mm. The resulting crushed feed stream 2 is then passed to an alkaline leaching circuit 110, where it is contacted with a solution comprising ammonia, ammonium sulfate 19 with / without ammonium chloride, and ammonia top-up 3 and 22 to dissolve copper. The alkaline leaching circuit is operated at, for example, about 50°C, atmospheric pressure, pH about 9.0, and about 10% solids. The resulting alkaline leached slurry 4 is subjected to a solid-liquid separation step 120, such as with a concentrator or multiple concentrators with washing action, and the ammonia leached liquid 6 is introduced into a solvent extraction circuit 160.

[0127] The thickener underflow 5 is introduced into the ammonium sulfate leach loop 130 where it reacts with a solution containing ammonium sulfates 24 and 32 and ammonium sulfate supplement 7. Air 8 is introduced into the leach loop 130. The ammonium sulfate leach is operated at about 100°C, about Eh 120 mV (Ag / AgCl electrode), and about 10% solids. The ammonium sulfate leach effluent 9 is introduced into the thickener 140. The thickener underflow 11 is introduced into the filter 150 where the thickened slurry is filtered. The resulting filter cake is washed with water 12 and the filtrate and wash filtrate are combined with the thickener overflow 10 and the ammonia leach liquor 6.

[0128] The pregnant leach liquor is introduced into the copper solvent extraction loop 160 where it is mixed with a copper extractant (e.g., a commercially available oxime extractant such as LIX84I TM ) is contacted. Copper is loaded onto the copper extractant, and the copper loaded extractant 14 is separated from the raffinate 19. The loaded extractant 14 reacts with dilute sulfuric acid 16 or anolyte, the anolyte coming from the copper electrowinning stage 180 of the copper stripping stage 170, to produce a loaded stripping liquid 15, the loaded stripping liquid 15 comprising copper and copper depleted extractant. The stripped organic matter (not shown) is recycled (not shown) to the extraction loop 160 to extract more copper. In the copper electrowinning stage 180, a copper product 18 is recovered from the copper loaded stripping liquid 15.

[0129] The copper-depleted raffinate 19 comprising ammonia and ammonium sulfate is introduced into the ammonia leaching circuit 110 to recover more metal. The remaining filtrate 29 is introduced into the ammonia recovery circuit 190, where steam 21 is used to strip ammonia 22. The recovered ammonia 22 is reused in the process, in particular, for example, in the ammonia leaching 110.

[0130] The ammonia-free liquor 24 is introduced into the ammonium sulfate leaching 130 and the crystallizer 200, where the condensate 25 is removed by forced evaporation and the lithium ammonium sulfate 26 is crystallized. The discharge of the crystallizer is subjected to solid-liquid separation using a centrifuge 210, and the centrifuged liquid 27 is introduced into the ammonium sulfate leaching 130. The lithium ammonium sulfate 28 is calcined in the kiln 220, where the solid (lithium sulfate 30) is collected for sale, and the exhaust gas 29 is collected in a wet scrubber using wash water 31 to recover the ammonium sulfate solution 32. The solution is introduced into the ammonium sulfate leaching 130.

[0131] Implementation 3

[0132] This embodiment describes a method for recovering metals from a lithium-ion battery feed comprising one or more types of metal oxides. In this particular embodiment, the feed comprises copper metal and metal oxides of at least cobalt, lithium, manganese and nickel.

[0133] The method comprises an initial leaching step in which lithium ion battery waste (possibly mixed with other electronic waste sources) is subjected to alkaline leaching with a first leaching solution comprising ammonium sulfate. In this particular embodiment, the first leaching solution also comprises ammonia, which has been found to enhance the leaching process as previously described. The leaching is carried out at atmospheric pressure and ambient temperature. However, the leaching can be carried out at an elevated temperature, for example, at a temperature below the boiling point of the leaching solution.

[0134] The alkaline leaching oxidizes the copper element contained in the lithium ion battery into soluble copper ions and reduces or otherwise releases nickel, cobalt, manganese and lithium ions contained in batteries such as nickel manganese cobalt (NMC), lithium cobalt oxide (LCO) and lithium ion manganese oxide (LMO). Thus, the leaching results in the formation of a first leachate containing soluble ions of cobalt, copper, lithium, manganese and nickel and a first solid residue.

[0135] Then, the first leachate is separated from the first solid residue.

[0136] The first solid residue contains low-value materials such as iron and aluminum, but may also contain residual cobalt, lithium, manganese and nickel compounds depending on the type of lithium-ion battery waste. For example, when the feed contains lithium iron phosphate (LFP) and lithium nickel cobalt aluminum oxide (NCA) batteries, some cobalt, lithium and nickel will be retained in the first solid residue.

[0137] The amount of cobalt, lithium, manganese and nickel may be sufficient to make further recovery of these metals economically feasible and therefore desirable. If so, the first solid residue may be subjected to a further leaching step with a second leaching solution comprising ammonium sulfate and preferably ammonium chloride. The second leaching is carried out at atmospheric pressure and ambient temperature. However, as described above, the second leaching can be carried out at an elevated temperature, for example at a temperature below the boiling point of the leaching solution. The second leaching can be an oxidative leaching. That is, an oxidant such as air, hydrogen peroxide, hypochlorite, etc. can be used during the leaching process to help recover the metals. Typically, for feeds containing NCA and / or NMC battery materials, an oxidant is not required because the amount of cobalt, nickel and manganese present is sufficient to provide a sufficiently high redox half-cell potential of>100mV. However, if the redox half-cell potential is below 100mV, as is the case with typical LFP battery waste feeds, then the oxidant assists or enhances the leaching process.

[0138] The second leaching provides a second leachate comprising soluble ions of cobalt, lithium, manganese and nickel and a second solid residue.

[0139] The second leachate is then separated from the second solid residue. As described above, the second solid residue may contain commercially recoverable amounts of residual cobalt, lithium, manganese and nickel, depending on the type of battery present.

[0140] In order to further recover these metals, the second solid residue is subjected to a particle size separation treatment to separate the first solid residue into a coarse fraction and a fine fraction. The fine fraction contains >80% of the residual nickel and also contains some residual cobalt, lithium and manganese. The fine fraction is acid leached, for example with sulfuric acid, to provide a third leachate containing cobalt, lithium, manganese and nickel ions and a third solid residue. The third leaching is carried out at atmospheric pressure and ambient temperature. However, as mentioned above, the third leaching can be carried out at an elevated temperature, for example at a temperature below the boiling point of the leaching solution.

[0141] Then, the third leachate is separated from the third solid residue.

[0142] It will be appreciated that in alternative embodiments the third acid leaching step is omitted.

[0143] Aluminium, iron and phosphates are not extracted in significant amounts and are typically retained in the first, second and / or third solid residues. As such, the leaching process is selective for higher value metals such as copper, cobalt, lithium, manganese and nickel.

[0144] The first, second and third leachates may then be combined to form a combined leachate, which may then be subjected to a number of steps to selectively recover cobalt, copper, lithium, manganese and nickel.

[0145] To recover manganese, the combined leachate is subjected to an oxidation step in the presence of ammonia to precipitate manganese in the form of manganese oxides, such as Mn2O3, Mn3O4 and / or MnO2 (but not MnO). The inventors have found that, where the leachate also contains cobalt ions, the presence of ammonia is important for complexing the cobalt ions to retain them in the form of soluble Co(III) ions and to prevent the formation of CoO precipitates. The manganese oxide precipitate can then be recovered from the combined leachate using any solid-liquid separation method known to those skilled in the art, such as filtration.

[0146] The combined leachate may then be subjected to a solvent extraction step to extract copper and / or nickel. The copper and / or nickel loaded solvent may then be separated from the combined leachate, followed by recovery of copper and / or nickel from the solvent. Copper and nickel may be recovered from the solvent via stripping with a stripping agent such as sulfuric acid. Typically, nickel may be selectively stripped with a lower residual acid concentration than copper, for example in the range of about pH 1 to 4, followed by stripping of copper by increasing the acid concentration, for example to greater than about 50 g / L H2SO4. This two-stage extraction allows for selective separation of copper and nickel.

[0147] In an alternative embodiment, copper and nickel may be recovered prior to recovering manganese.

[0148] The combined leachate may then be further processed to recover the cobalt. In this embodiment, the cobalt is recovered via a cobalt precipitation process, whereby the combined leachate is treated with a sulfide, such as hydrogen sulfide gas or ammonium sulfide, to precipitate cobalt sulfide. The cobalt sulfide may then be recovered from the combined leachate using any solid-liquid separation method known to those skilled in the art, such as filtration.

[0149] The combined leachate, now substantially depleted of cobalt, copper, manganese and nickel, can be further processed to recover ammonia, ammonium salts and lithium.

[0150] Ammonia is stripped from the leachate and the recovered ammonia is recycled and reused as part of the first leach solution. The lithium in the leachate is typically in the form of lithium sulfate. The lithium sulfate can be crystallized with ammonium sulfate (e.g., via an evaporation process) in the form of lithium ammonium sulfate and separated from the leachate. The lithium ammonium sulfate can then be thermally treated to decompose the lithium ammonium sulfate into lithium sulfate solid, ammonia gas, and sulfur trioxide gas. The ammonia and sulfur trioxide gas can be captured and reacted with water (e.g., in a wet scrubber) to form ammonium sulfate, which can then be recycled to the first and / or second leaching steps.

[0151] refer to Figure 2 The process is described in more detail. Figure 2 A schematic diagram of the process flow of the method of the present invention according to the above-mentioned embodiment is shown.

[0152] Figure 2 The process shown describes the recovery of nickel product 27, copper product 32, cobalt product 37 and lithium product 48. In this embodiment, feed stream 1 is subjected to a pre-treatment process, such as crushing 100 to <5 mm, such as <1 mm, to make feed stream 1 suitable for further processing. The resulting crushed feed stream 2 is then sent to an alkaline leaching circuit 110, where it is contacted with a liquid containing ammonia, ammonium sulfate 39 with / without ammonium chloride, and ammonia supplements 3 and 40 to dissolve metal species. The conditions of the alkaline leaching circuit 110 include about 5-10% solids, about 50°C, atmospheric pressure, a residence time of about 12 hours, a pH of about 9, ammonia about 200g / L ammonium sulfate, and about 20g / L ammonium chloride (if present).

[0153] The resulting alkaline leach slurry 4 is subjected to a solid-liquid separation step 120 , for example using a thickener or a plurality of thickeners with a washing action, and the ammoniacal leach liquor 6 is introduced into a manganese oxide precipitation circuit 180 .

[0154] The concentrator underflow 5 is introduced into the ammonium sulfate leach loop 130 where it is contacted with a solution containing ammonium sulfate 47 and ammonium sulfate supplement 7. The conditions in the ammonium sulfate leach loop 130 include about 5-10% solids, about 100-105° C., atmospheric pressure, about 4-12 hours residence time, about 200 g / L ammonium sulfate and 20 g / L ammonium chloride.

[0155] The ammonium sulfate leach effluent 8 is introduced into a screen 140, e.g., 75-500 μm, e.g., about 180 μm, to separate the coarse and fine fractions of particles. The coarse fraction 9 is stored, and the fine fraction 10 is introduced into a thickener 150. The thickener overflow, e.g., ammonium sulfate leach liquor 11, is introduced into a manganese oxide precipitation circuit 180.

[0156] The thickener underflow 12 is introduced into the acid leach loop 160 where it is contacted with sulfuric acid 13. The conditions in the acid leach loop 160 include a temperature in the range of about 20 to 100° C., such as 70° C., a pH of less than about 3, such as about 1.5, a residence time of about 4 to 12 hours, 30% solids and 98% acid additive.

[0157] The acid leach effluent 14 is filtered 170 and the solids are washed to produce a leach residue 15 which is stored and an acid leach liquor 17 which is introduced into a manganese oxide precipitation circuit 180 .

[0158] The leach liquors 6, 11 and 17 are introduced into a manganese oxide precipitation circuit 180 where air 18 is passed into the solution to force the manganese oxide to precipitate. The precipitated slurry 19 is subjected to solid-liquid separation by thickening and filtering 190. The manganese product 20 is washed and stored.

[0159] The rich leaching liquid 21 after manganese precipitation is introduced into the copper and nickel solvent extraction circuit 200, in which it is mixed with a copper and nickel extractant (such as a commercially available oxime extractant such as LIX84I TM ) is contacted. Copper and nickel are loaded onto the copper extractant, and the loaded extractant 23 is separated from the raffinate 22. In the nickel stripping stage 210, the loaded extractant 23 is contacted with dilute sulfuric acid 24, such as 150 g / L sulfuric acid, to produce a loaded stripping liquid 25 containing nickel and a nickel-depleted extractant 28. In the copper extraction stage 220, the nickel-depleted extractant 28 is contacted with a dilute sulfuric acid liquid 29, such as 200 g / L sulfuric acid, to produce a loaded extraction liquid 30 containing copper. The stripped organic matter (not shown) is recycled (not shown) to the extraction loop 200 to extract more copper and nickel. The nickel product 27 (on the surface in the form of nickel sulfate) is recovered from the stripping liquid 25 loaded with nickel in the nickel crystallization stage 230. In the copper electrolysis stage 240, the copper product 32 (on the surface in the form of copper sulfate) is recovered from the stripping liquid 30 loaded with copper.

[0160] The copper- and nickel-depleted raffinate 22 is introduced into the cobalt recovery loop 250, and a precipitant, such as hydrogen sulfide gas 33, is added to the cobalt recovery loop 250 to promote the precipitation of cobalt sulfide. The obtained slurry 34 is subjected to solid-liquid separation, for example, by a concentrator and a filter 260, and washed with water 35 to produce a cobalt product 37.

[0161] Most of the resulting filtrate 39 (containing ammonia and ammonium sulfate) is introduced into the ammonia leaching circuit 110 to recover more metals. The remaining filtrate 38 is introduced into the ammonia recovery circuit 270, where ammonia 40 is stripped using steam 41. The recovered ammonia 40 is reused in the process, in particular, for example, in the ammonia leaching 110.

[0162] The ammonia-free liquid 42 is introduced into the ammonium sulfate leaching 130 and also into the crystallizer 280, where the condensate 43 is removed by forced evaporation and lithium ammonium sulfate 46 is crystallized. The crystallizer discharge is subjected to solid-liquid separation using a centrifuge 290, and the centrifuged liquid 45 is introduced into the ammonium sulfate leaching 130. The lithium ammonium sulfate 46 intermediate is calcined in the kiln 300, where the solid lithium sulfate 48 is collected for sale, and the waste gas 47 is collected in a wet scrubber with wash water 49 to recover the ammonium sulfate solution 50.

[0163] Example

[0164] Example 1

[0165] This example discloses a single stage alkaline leaching of raw lithium-ion nickel manganese cobalt 622 (NMC622) battery scrap using a leaching solution of ammonium sulfate, ammonia and ammonium chloride.

[0166] The NMC battery fragments contained 22.9 wt% copper, 12.5 wt% nickel, 4.9 wt% cobalt, 6.2 wt% manganese and 2.94 wt% lithium in elemental terms. The copper element was present in an amount sufficient to provide a redox potential (Ag / AgCl electrode) of less than -150 mV during leaching.

[0167] The NMC battery scrap was reacted with a leaching aqueous solution containing 169 g / L ammonium sulfate, 46 g / L ammonia and 14.5 g / L ammonium chloride at 3.8 wt% solid loading. The leaching was carried out at a pH of 9.5, atmospheric pressure and a temperature of 50°C for 2 hours.

[0168] The extraction rates of nickel, cobalt, copper, lithium and manganese in the leaching solution were 97.5%, 96.4%, 99.3%, 95.5% and 96.1%, respectively.

[0169] Although not disclosed in this example, nickel, cobalt, copper, lithium and manganese can be selectively recovered from the leachate using the method disclosed in the present invention. Similarly, the ammonium sulfate, ammonia and ammonium chloride can be recovered for reuse using the method disclosed in the present invention.

[0170] Example 2

[0171] This example discloses a three-stage leaching of a mixed feed of raw lithium-ion nickel manganese cobalt 622 (NMC622), lithium-ion nickel manganese cobalt 811 (NMC811), lithium nickel cobalt aluminum oxide (NCA), and lithium iron phosphate (LFP) battery fragments using a leaching solution of ammonium sulfate, ammonia, and ammonium chloride.

[0172] An equal weight mixture of NMC811, NMC622, NCA and LFP battery fragments was prepared, which contained 7.01wt% copper, 14.5wt% nickel, 2.48wt% cobalt, 2.16wt% manganese and 2.69wt% lithium. The copper element was present in an amount sufficient to provide a redox potential (Ag / AgCl electrode) of less than -150mV during leaching.

[0173] The battery scrap mixture was first subjected to alkaline leaching in a solution containing 215 g / L ammonium sulfate, 105 g / L ammonia and 21 g / L ammonium chloride at 9.8 wt% solid loading. The leaching was carried out at a pH range of 9.4-9.9, atmospheric pressure and a temperature of 50°C for 6 hours.

[0174] The extraction rates of nickel, cobalt, copper, lithium and manganese in the leaching solution were 37.6%, 57.6%, 81.5%, 47.8% and 67.9%, respectively. The metals were mainly extracted from NMC622 and NMC811 batteries.

[0175] The solid residue of the first leaching was found to contain 1.46 wt% copper, 10.2 wt% nickel, 1.19 wt% cobalt, 0.78 wt% manganese and 1.59 wt% lithium.

[0176] The solid residue was separated from the leachate and subjected to a second leaching using a solution containing 343 g / L of ammonium sulfate and 34 g / L of ammonium chloride at a solid loading of 6.9 wt%. The leaching was carried out in a solution such that the natural pH was in the range of 5.1-5.3 and the natural redox potential was 165 mV (Ag / AgCl electrode). The leaching was carried out at atmospheric pressure and a temperature of 100° C. for 6 hours.

[0177] The extraction rates of nickel, cobalt, copper, lithium and manganese reached 59.4%, 82.2%, 33.8%, 94.3% and 94.7% respectively. Except for nickel, all other metals were extracted from all types of batteries. Nickel was mainly extracted from NMC811 and NMC622 materials, which were not leached in the previous alkaline leaching.

[0178] In the two leaching stages, the extraction rates of nickel, cobalt, copper, lithium and manganese in the leaching solution reached 74.7%, 92.5%, 87.7%, 97.0% and 98.3%, respectively.

[0179] The solid residue from the second leach was initially screened at 180 microns to remove coarse material, particularly steel and aluminium foil. The undersize material contained 1.27 wt% copper, 5.44 wt% nickel, 0.28 wt% cobalt, 0.95 wt% manganese and 0.12 wt% lithium.

[0180] The solid residue was re-slurried in water to 30% solids, followed by addition of sulfuric acid to a target pH of 1.50. After leaching for 6 hours at 70°C, the extraction yields of nickel, cobalt, copper, lithium and manganese reached 99.5%, 99.0%, 98.8%, 96.3% and 92.6%, respectively. The acid consumption was significantly lower (<200kg / t) than the equivalent pure sulfuric acid process (>1200kg / t).

[0181] In all three leaching stages, the extraction rates of nickel, cobalt, copper, lithium and manganese in the leachate (including metal losses associated with screening) reached 96.8%, 98.2%, 97.7%, 98.6% and 93.0% respectively.

[0182] The leachates from the three leaching steps can be combined and subsequently treated using the method described in the present invention to selectively recover nickel, cobalt, copper, lithium and manganese. Likewise, ammonium sulfate, ammonia and ammonium chloride can be recovered for reuse using the method described in the present invention.

[0183] Example 3

[0184] This example discloses the oxidative leaching of raw lithium iron phosphate (LFP) battery scrap using a single stage aqueous leaching solution of ammonium sulfate and ammonium chloride.

[0185] Calculated as elements, the LFP battery fragments contained 6.7 wt % copper and 1.99 wt % lithium.

[0186] The LFP cell fragments were reacted with an aqueous leachate solution containing 350 g / L ammonium sulfate and 17.7 g / L ammonium chloride at 4.0 wt% solid loading. Air was added as an oxidant to reach a target redox potential of +150 mV (Ag / AgCl electrode).

[0187] Leaching was performed at a natural pH ranging from 4.9 to 5.2, atmospheric pressure and a temperature of 100° C. for 4 hours.

[0188] The extraction rates of copper in the leaching solution were 83.4% and 92.5%, respectively. The total extracted iron was only 0.5%.

[0189] Although not disclosed in this example, copper and lithium can be selectively recovered from the leachate using the method disclosed in the present invention. Similarly, ammonium sulfate and ammonium chloride can be recovered for reuse using the method disclosed in the present invention.

[0190] Example 4

[0191] This example discloses the leaching of raw lithium nickel manganese cobalt 811 (NMC811) battery scrap using a single stage aqueous leaching solution of ammonium sulfate and ammonium chloride.

[0192] Calculated in terms of elements, the NMC811 battery fragment contained 2.46 wt% copper, 22.2 wt% nickel, 2.72 wt% cobalt, 1.72 wt% manganese and 2.83 wt% lithium.

[0193] The NMC811 battery fragments were reacted with an aqueous leaching solution containing 355 g / L ammonium sulfate and 17.7 g / L ammonium chloride at 4.0 wt% solid loading. Copper metal was additionally added in an amount of 250 kg / t, which may be introduced in the form of electronic scrap, such as printed circuit boards, etc.

[0194] Leaching was performed at a natural pH ranging from 4.7 to 5.5, a natural redox potential of about 15 to 150 mV (Ag / AgCl electrode), atmospheric pressure and a temperature of 100° C. for 4 hours.

[0195] The extraction rates of copper, nickel, cobalt, manganese and lithium in the leaching solution were 60.1%, 67.0%, 79.3%, 94.8% and 95.5%, respectively.

[0196] Although not disclosed in this example, copper, nickel, cobalt, manganese and lithium can be selectively recovered from the leachate using the method disclosed in the present invention. Similarly, ammonium sulfate and ammonium chloride can be recovered for reuse using the method disclosed in the present invention.

[0197] Example 5

[0198] This example discloses the leaching of raw lithium nickel cobalt aluminum oxide (NCA) battery scrap using a single stage aqueous leaching solution of ammonium sulfate and ammonium chloride.

[0199] In terms of elements, the NCA battery fragments contained 0.95 wt % copper, 24.3 wt % nickel, 2.77 wt % cobalt, 0.02 wt % manganese and 3.20 wt % lithium ions.

[0200] The NCA battery fragments were reacted with an aqueous leaching solution containing 355 g / L ammonium sulfate and 17.7 g / L ammonium chloride at 4.0 wt% solid loading. Copper metal was additionally added in an amount of 250 kg / t, which may be introduced in the form of electronic scrap, such as printed circuit boards, etc.

[0201] Leaching was performed at a natural pH ranging from 4.5 to 4.9, a natural redox potential of about -16 to 30 mV (Ag / AgCl electrode), atmospheric pressure and a temperature of 100° C. for 4 hours.

[0202] The extraction rates of copper, nickel, cobalt, manganese and lithium in the leaching solution were 87%, 33.4%, 58.9%, 58.2% and 94.6%, respectively.

[0203] Although not disclosed in this example, copper, nickel, cobalt, manganese and lithium can be selectively recovered from the leachate using the method disclosed in the present invention. Similarly, ammonium sulfate and ammonium chloride can be recovered for reuse using the method disclosed in the present invention.

[0204] Example 6

[0205] This example discloses alkaline leaching of raw lithium-ion manganese oxide (LMO) battery scrap using a single-stage aqueous leaching solution of ammonia, ammonium sulfate, and ammonium chloride.

[0206] Calculated by elements, the LMO battery scrap contained 3.28 wt% copper, 3.65 wt% nickel, 1.24 wt% cobalt, 27.9 wt% manganese and 2.52 wt% lithium.

[0207] The LMO battery fragments were reacted with an aqueous leaching solution containing 45 g / L ammonia, 180 g / L ammonium sulfate and 18 g / L ammonium chloride at 4.0 wt% solid loading. Copper metal was additionally added in an amount of 250 kg / t, which may be introduced in the form of electronic scrap, such as printed circuit boards, etc.

[0208] Leaching was performed at a natural pH ranging from 8.8 to 9.1, a redox potential of about -123 to -250 mV (Ag / AgCl electrode), atmospheric pressure and a temperature of 50°C for 4 hours.

[0209] The extraction rates of copper, nickel, cobalt, manganese and lithium in the leaching solution were 84.0%, 89.7%, 93.3%, 71.8% and 97.3%, respectively.

[0210] Although not disclosed in this example, copper, nickel, cobalt, manganese and lithium can be selectively recovered from the leachate using the method disclosed in the present invention. Similarly, ammonia, ammonium sulfate and ammonium chloride can be recovered for reuse using the method disclosed in the present invention.

[0211] Example 7

[0212] This example discloses alkaline leaching of raw lithium cobalt oxide (LCO) battery scrap using a single stage aqueous leaching solution of ammonia, ammonium sulfate and ammonium chloride.

[0213] Calculated as elements, the LCO battery scrap contained 5.42 wt% copper, 28.6 wt% cobalt and 3.46 wt% lithium.

[0214] The LCO cell scraps were reacted with an aqueous leachate solution containing 45 g / L ammonia, 180 g / L ammonium sulfate, and 18 g / L ammonium chloride at 4.0 wt% solids loading.

[0215] Leaching was carried out for 2 hours at a natural pH of 9.2, a redox potential of -150 mV (Ag / AgCl electrode), atmospheric pressure and a temperature of 50° C. After 2 hours, the extraction rates of copper, cobalt and lithium in the leachate were 93.8%, 24.1% and 25.9%, respectively.

[0216] Then 100 kg / t of copper was added and leaching was continued for another 2 hours. After another 2 hours of leaching, the extraction rates of copper, cobalt and lithium in the leaching solution reached 97.6%, 67.5% and 68.9% respectively.

[0217] This example shows that the addition of copper results in higher metal extraction rates.

[0218] Although not disclosed in this example, copper, cobalt and lithium can be selectively recovered from the leachate using the method disclosed in the present invention. Similarly, ammonia, ammonium sulfate and ammonium chloride can be recovered for reuse using the method disclosed in the present invention.

[0219] Example 8

[0220] This example discloses a three-stage leaching of a mixed feed of raw lithium nickel manganese cobalt 622 (NMC622), lithium ion nickel manganese cobalt 811 (NMC811), lithium nickel cobalt aluminum oxide (NCA), and lithium iron phosphate (LFP) battery scraps using a leaching solution of ammonium sulfate and ammonia. No ammonium chloride was added.

[0221] An equal weight mixture of NMC811, NMC622, NCA and LFP battery fragments (containing 7.01% copper, 14.5% nickel, 2.48% cobalt, 2.16% manganese and 2.69% lithium) was reacted in a solution containing 220 g / L ammonium sulfate and 110 g / L ammonia at 9.1% solids and 50°C. After leaching for 6 hours at a pH of 9.5 to 9.9 and a redox potential of less than -90 mV (Ag / AgCl electrode), the extraction rates of nickel, cobalt, copper, lithium and manganese reached 58.8%, 45.8%, 49.4%, 47.4% and 78.3%, respectively. The metals were mainly extracted from NMC622 and NMC811 batteries.

[0222] The solid residue of the first leach was found to contain 6.17% copper, 8.55% nickel, 0.468% cobalt, 0.67% manganese and 2.10% lithium.

[0223] The solid residue was reacted in a solution containing 354 g / L ammonium sulfate at 5.1% solids and 100°C. After 6 hours of leaching (wherein the natural pH was 4.2-5.4 and the natural redox potential was 360-530 mV (Ag / AgCl electrode)), the extraction rates of nickel, cobalt, copper, lithium and manganese reached 15.1%, 77.6%, 67.7%, 75.5% and 8.5%, respectively. Except for nickel, other metals were extracted from all types of batteries. Nickel was mainly extracted from NMC811 and NMC622 materials, which were not leached in the primary leaching.

[0224] The extraction rates of nickel, cobalt, copper, lithium and manganese in the two leaching stages reached 64.5%, 85.5%, 87.5%, 86.1% and 79.8%, respectively.

[0225] The solid residue from the second leach was initially screened at 180 microns to remove coarse material, particularly steel and aluminium foil. The undersize contained 1.61% copper, 8.2% nickel, 0.49% cobalt, 0.69% manganese and 0.59% lithium.

[0226] The solid residue was re-slurried in water to 30% solids followed by addition of sulfuric acid to a target pH of 1.90. After leaching for 6 hours at 70°C, the extraction yields of nickel, cobalt, copper, lithium and manganese reached 58.9%, 98.3%, 37.1%, 64.9% and 7.0%, respectively. The acid consumption was significantly lower (<100kg / t) than the equivalent pure sulfuric acid process (>1200kg / t). Higher metal extraction yields are expected to be achieved with increasing acid addition.

[0227] The extraction rates (including metal losses associated with screening) for nickel, cobalt, copper, lithium and manganese in all three leaching stages reached 85.7%, 92.3%, 99.7%, 95.5% and 80.0%, respectively.

[0228] Example 9

[0229] This example discloses the leaching of a mixture of lithium iron phosphate (LFP) and nickel cobalt aluminum (NCA) battery fragments using a single-stage aqueous leaching solution of ammonium sulfate and ammonium chloride, with a mass ratio of LFP:NCA of 4:1.

[0230] Calculated in terms of elements, the battery fragments contained 0.26 wt % copper, 4.39 wt % nickel, 0.50 wt % cobalt, 19.0 wt % iron and 1.99 wt % lithium.

[0231] The battery scraps were reacted with an aqueous leachate solution containing 230 g / L ammonium sulfate, 23 g / L ammonium chloride and 5.5 g / L copper (in the form of copper sulfate) at a solid loading of 4.9 wt%. Copper sulfate was added due to the low copper grade of the battery scraps.

[0232] Leaching was performed at a natural pH ranging from 4.80 to 5.13, a redox potential of +123 to +180 mV (Ag / AgCl electrode), atmospheric pressure and a temperature of 100° C. for 8 hours.

[0233] The extraction rates of nickel, cobalt, iron and lithium in the leaching solution were 44.0%, 75.7%, 0.43% and 94.7%, respectively.

[0234] Although not disclosed in this example, copper, nickel, cobalt and lithium can be selectively recovered from the leachate using the method disclosed in the present invention. Similarly, ammonium sulfate and ammonium chloride can be recovered for reuse using the method disclosed in the present invention.

[0235] Example 10

[0236] This example discloses the leaching of a mixture of lithium iron phosphate (LFP) and nickel cobalt aluminum (NCA) battery fragments using a single-stage leaching aqueous solution of ammonium sulfate, with a mass ratio of LFP:NCA of 4: 1. No ammonium chloride is added during the leaching process.

[0237] Calculated in terms of elements, the battery fragments contained 0.26 wt % copper, 4.39 wt % nickel, 0.50 wt % cobalt, 19.0 wt % iron and 1.99 wt % lithium.

[0238] The battery scraps were reacted with an aqueous leachate solution containing 230 g / L ammonium sulfate and 5.5 g / L copper (in the form of copper sulfate) at 4.9 wt% solids loading. Copper sulfate was added due to the low copper grade of the battery scraps.

[0239] Leaching was performed at a natural pH ranging from 4.22 to 5.05, a redox potential of +91 to +126 mV (Ag / AgCl electrode), atmospheric pressure and a temperature of 100° C. for 8 hours.

[0240] The extraction rates of nickel, cobalt, iron and lithium in the leaching solution were 20.5%, 43.4%, 0.26% and 81.6%, respectively.

[0241] Although not disclosed in this example, copper, nickel, cobalt, manganese and lithium can be selectively recovered from the leachate using the method disclosed in the present invention. Similarly, ammonium sulfate and ammonium chloride can be recovered for reuse using the method disclosed in the present invention.

[0242] It should be understood that the invention disclosed and defined in this specification can be extended to all alternative combinations of two or more individual features mentioned or evident from the text or drawings. All these different combinations constitute various optional aspects of the present invention.

Claims

1. A method for recovering metals from electronic waste or leached residues thereof, wherein the electronic waste or leached residues contain copper and one or more lithium compounds, the method comprising: Leaching the electronic waste or leached residue with a leaching solution comprising ammonium sulfate in the presence of an oxidant to provide a leachate comprising copper ions and lithium ions and a solid residue; as well as The leachate and the solid residue are separated.

2. The method of claim 1, wherein: The copper element is present in an amount sufficient to provide a redox potential of -100 mV or less, the redox potential being measured using an Ag / AgCl reference electrode; preferably, the redox potential is -150 mV or less.

3. The method according to claim 1 or 2, wherein: The oxidant is present in an amount sufficient to provide a redox potential of +50 mV or higher, as measured using an Ag / AgCl reference electrode; preferably, the redox potential is +100 mV or higher, more preferably, the redox potential is +150 mV or higher.

4. A method as claimed in any one of the preceding claims, wherein: The temperature is from about 0°C to a temperature at or below the boiling point of the leaching solution under leaching operating conditions; preferably, the temperature is from about 40°C to a temperature at or below the boiling point of the leaching solution under leaching operating conditions.

5. A method as claimed in any one of the preceding claims, wherein: The leaching was carried out at atmospheric pressure.

6. A method as claimed in any one of the preceding claims, wherein: The leaching is performed for up to 24 hours; preferably, the leaching is performed for up to 18 hours; more preferably, the leaching is performed for up to 12 hours; most preferably, the leaching is performed for up to 8 hours; additionally or alternatively, the leaching is performed for at least 0.5 hours; preferably, the leaching is performed for at least 1 hour; more preferably, the leaching is performed for at least 1.5 hours; most preferably, the leaching is performed for at least 2 hours.

7. A method as claimed in any one of the preceding claims, wherein: The method also includes recovering copper ions from the leachate.

8. The method of claim 7, wherein: After the step of recovering copper ions from the leachate, the method further comprises: crystallizing lithium ammonium sulfate from the leachate, and The crystallized lithium ammonium sulfate is thermally decomposed to form a gas comprising ammonia and sulfur oxides and solid lithium sulfate.

9. A method as claimed in any one of the preceding claims, wherein: Prior to the step of crystallizing lithium ammonium sulfate, the leachate is treated so that the leachate is ammonia-depleted, copper-depleted, nickel-depleted, cobalt-depleted, manganese-depleted leachate and / or the leachate is substantially free of ammonia, aluminum, copper, iron, nickel, cobalt or manganese.

10. A method as claimed in any one of the preceding claims, wherein: The electronic waste further contains one or more transition metals, the oxidant is one or more transition metal oxides, and the leachate contains ions of the one or more transition metals.

11. The method of claim 10, wherein: The one or more transition metals are selected from the group consisting of cobalt, manganese and / or nickel.

12. A method as claimed in any one of the preceding claims, wherein: The electronic waste further comprises nickel, and the leaching solution further comprises ammonia in an amount such that the pH of the leaching solution is about 8.5 to about 10.5, wherein the leachate comprises at least copper ions, lithium ions, and nickel ions.

13. The method of claim 12, wherein: The leach solution comprises ammonia and ammonium sulfate in a ratio of about 1:2 to about 1:

20.

14. The method according to claim 12 or 13, wherein: The method also includes simultaneously recovering copper ions and nickel ions from the leachate via a solvent extraction process.

15. The method according to any one of claims 1 to 11, wherein: The electronic waste further comprises cobalt, and the leaching solution further comprises ammonia in an amount such that the pH of the leaching solution is about 8.5 to about 10.5, wherein the leachate comprises at least copper ions, lithium ions, and cobalt ions.

16. The method of claim 15, wherein: The method also includes recovering copper ions from the leachate and precipitating cobalt from the leachate after removing the copper ions.

17. The method of claim 16, wherein: The step of precipitating cobalt from the leachate includes precipitating cobalt sulfide from the leachate.

18. The method according to any one of claims 1 to 11, wherein: The electronic waste further contains manganese, the leaching solution further contains a leaching solution containing manganese ions, and the method further comprises: treating the leachate with an oxidizing agent to form a precipitate of manganese and to provide a manganese-depleted leachate comprising copper ions and lithium ions; and The manganese precipitate and the manganese-depleted leachate are separated.

19. The method of claim 18, wherein: The oxidant is air.

20. A method as claimed in any one of the preceding claims, wherein: The electronic waste further comprises iron and aluminum, the solid residue comprises iron and aluminum, the leachate is an iron-depleted, aluminum-depleted leachate and / or the leachate substantially does not comprise iron or aluminum.

21. The method of claim 1, wherein: The electronic waste contains copper element and one or more compounds of cobalt, lithium and nickel, wherein the leaching solution further contains ammonia, and the leaching solution contains cobalt ions, copper ions, lithium ions and nickel ions; after the step of separating the leaching solution and the solid residue, the method further comprises: subjecting the leachate to a solvent extraction step to remove copper ions and nickel ions from the leachate and form a copper-depleted, nickel-depleted leachate; subjecting the copper-depleted, nickel-depleted leachate to a precipitation step to remove cobalt ions from the copper-depleted, nickel-depleted leachate and form a cobalt-depleted, copper-depleted, nickel-depleted leachate; and Recovering lithium from the cobalt-depleted, copper-depleted and nickel-depleted leaching solutions, Before the step of recovering lithium, the leaching solution is subjected to an ammonia recovery step, so that during the process of recovering lithium, the cobalt-depleted, copper-depleted and nickel-depleted leaching solution is substantially free of ammonia.

22. The method of claim 21, wherein: The cobalt ions include Co 2+ ions, and prior to subjecting the leachate to a solvent extraction step, the method further comprises treating the leachate with an oxidizing agent to remove the Co 2+ Ion oxidation to Co 3+ ion.

23. The method of claim 1, wherein: The electronic waste contains copper and one or more compounds of cobalt, lithium, manganese and nickel, wherein the leaching solution further contains ammonia, and the leaching solution contains cobalt ions, copper ions, lithium ions, manganese ions and nickel ions; After the step of separating the leachate and the solid residue, the method further comprises: The leachate is treated with an oxidizing agent to form a precipitate of manganese and to provide a manganese-depleted leachate containing cobalt in the form of 3+ ions of cobalt, copper, lithium and nickel; and separating the manganese precipitate and the manganese-depleted leaching solution; subjecting the manganese-depleted leachate to a solvent extraction step to remove copper ions and nickel ions from the manganese-depleted leachate and form a copper-depleted, manganese-depleted, nickel-depleted leachate; subjecting the copper-depleted, manganese-depleted, nickel-depleted leachate to a precipitation step to remove cobalt ions from the copper-depleted, manganese-depleted, nickel-depleted leachate to form a cobalt-depleted, copper-depleted, manganese-depleted, nickel-depleted leachate; and Recovering lithium from the cobalt-depleted, copper-depleted, manganese-depleted, and nickel-depleted leaching solutions; Before the step of recovering lithium, the leaching solution is subjected to an ammonia recovery step, so that during the process of recovering lithium, the cobalt-depleted, copper-depleted and nickel-depleted leaching solution is substantially free of ammonia.

24. The method of claim 1, wherein: The leachate solution further comprises ammonia, the leachate is a first leachate, the solid residue is a first solid residue, and after the step of separating the first leachate and the first solid residue, the method further comprises: leaching the solid residue with a second leach solution comprising ammonium sulfate to provide a second leachate and a second solid residue; and separating the second leachate and the second solid residue; leaching the second solid residue with an acid to provide a third leachate and a third solid residue; separating the third leachate and the third solid residue; and The first leachate, the second leachate and the third leachate are combined to form a combined leachate.

25. The method of claim 24, wherein: The electronic waste contains copper and one or more compounds of cobalt, lithium, manganese and nickel, and the method includes recovering one or more of cobalt, copper, lithium, manganese and nickel from the combined leachate.

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