Electrochemical membrane apparatus comprising electrochemical membrane reactors for removing and recovering elements from a leaching solution and related methods

Abstract

An electrochemical membrane apparatus comprising one or more anodes contained in one or more anode chambers; one or more cathodes contained in one or more cathode chambers adjacent to the one or more anode chambers; at least one ionic exchange membrane disposed between at least one of the one or more anode chambers and the one or more cathode chambers; an inlet configured to supply a leaching solution to the one or more cathode chambers; a power source electrically coupled to the reactor and configured to apply a current between the one or more anodes and the one or more cathodes; a purging system configured to introduce one or more of air, O2, and an inert gas to the reactor; a pH measurement system coupled to the reactor; and an outlet configured to discharge a purified leaching solution. Methods of separating and recovering elements are also disclosed.

Description

[0001] ELECTROCHEMICAL MEMBRANE APPARATUS COMPRISING ELECTROCHEMICAL MEMBRANE REACTORS FOR REMOVING AND RECOVERING ELEMENTS FROM A LEACHING SOLUTION AND RELATED METHODS

[0002] PRIORITY CLAIM

[0003] This application claims the benefit of the filing date of United States Provisional Patent Application Serial No. 63 / 582,216, filed September 12, 2023, for “ELECTROCHEMICAL MEMBRANE REACTORS FOR REMOVING IMPURITIES FROM SPENT LI-ION BATTERIES. MINES, MINING SLAG, MINING WASTE. BRINE, COAL, COAL ASH, AND SECONDARY SOURCES AND RELATED METHODS,’’ the disclosure of which is hereby incorporated herein in its entirety by this reference.

[0004] STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0005] This invention was made with government support under Contract No. DE-AC07- 05-ID14517 awarded by the United States Department of Energy. The government has certain rights in the invention.

[0006] TECHNICAL FIELD

[0007] This disclosure relates generally to electrochemical membrane apparatus. In particular, embodiments of the disclosure relate to electrochemical membrane apparatus comprising an electrochemical membrane reactor for separating and recovering valuable elements, and to related methods and systems.

[0008] BACKGROUND

[0009] The expanding of the electnc vehicle market brings with it exponential growth in the use of lithium (Li)-ion batteries (LIB or Li-ion batteries), which use transition metals, including cobalt (Co), nickel (Ni) and manganese (Mn), for their cathodes. The import reliance of Co, Ni and Mn in the United States is 78%, 48%, and 100% respectively, and these transition metals are listed as critical elements by the United States. Recycling spent LIBs is an effective strategy to mitigate the risk of supply chain disruption, but no recycling methodology' is perfect. Conventional hydrometallurgical approaches have technological barriers including high chemical consumption and negative environmental impact.

[0010] The consumption of Li-ion batteries grows exponentially in the United States, and in 2035, some states, such as California, are expected to stop fabricating gasoline vehicles, which are expected to be replaced by electric vehicles. The battery' demand in the United States was 526 gigawatt hours in 2020, and it is projected to increase 17 fold by 2030. However, about 95% of spent Li-ion batteries have ended up in landfills in the United States in recent years. The cost of conventional hydrometallurgy processes to recycle lithium ion batteries is about $10 / kg (USD).

[0011] Conventional hydrometallurgies, such as chemical precipitation, solvent extraction, electrodeposition, ionic exchange, or the combination of these methods, may have high chemical consumption and / or high negative environmental impact.

[0012] Conventional recycling methods that use acid leaching combined with precipitation use a considerable amount of sodium hydroxide (NaOH) to neutralize excessive acid. These methods remove the impurities by increasing the pH to about 6 to about 7. and then coprecipitating Co, Ni and Mn as the cathode precursor (e.g.. nickel manganese cobalt hydroxide (NixMnyCoz(OH)2) particles) by adding NaOH and a chelating agent (e.g., ammonium hydroxide (NH4OH)). However, the residue solution has additional Na2SO4 as an impurity mixed with the leached Li2SO4 and NH4OH. Low concentrations of Co2+, Ni2+and Mn2+ions are also present. When re-use of the residue solution is desired in order to synthesize NixMnyCoz(OH)2, the Na+, SO42’ and Li+ions have a detrimental effect on the particle size and particle density' of NixMnyCoz(OH)2, which may fail to meet industrial standards. Na+and Li+ions are very difficult to separate from each other as well. The residue solution is also directly discharged to the environment, causing pollution and wasting Li+ions.

[0013] Solvent extraction methods, used by some recyclers, have a high environmental impact and are only used in areas where environmental regulations are less strict. For example, Co may be removed with extractants, such as CYANEX® 272 (a dialkyl phosphinic acid extractant) and D2EHPA (di-(2-ethyl hexyljphosphoric acid), and Ni and Mn may be precipitated using sodium carbonate (Na2CO3). Both the spent extractant and the residue solution, which have high concentrations of Na+and Li+ions, and low concentrations of Ni2+. Co2+, and Mn2+ions, may cause significant environmental issues. Mining products, such as carbonatite, bauxite, coal, and others, and mine tailings, such as bauxite residue, coal ash, and the like, contain so-called "no value" elements, such as potassium (K), sodium (Na), silicon (Si), calcium (Ca), sulfur (S), chlorine (Cl), etc., so- called ‘'low value” elements, such as iron (Fe), lead (Pb), etc., so-called “middle value” elements, such as zinc (Zn), copper (Cu), aluminum (Al), etc., and so-called “high value” elements, such as nickel (Ni), cobalt (Co), gallium (Ga), molybdenum (Mo), rare earth elements, etc. Conventional technologies, such as methods using ion exchange resins, require several columns of cationic resin to remove impurities from rare earth elements. Solvent extraction requires several extractants to extract the high value elements, such as rare earth elements, from the leachate. Both of these methodologies are costly, inefficient, and have a negative environmental impact.

[0014] SUMMARY

[0015] An electrochemical membrane apparatus is disclosed comprising an electrochemical membrane reactor comprising one or more anodes contained in one or more anode chambers. One or more cathodes are contained in one or more cathode chambers adjacent to the one or more anode chambers. At least one ionic exchange membrane is disposed between at least one of the one or more anode chambers and the one or more cathode chambers. An inlet is configured to supply a leaching solution to the one or more cathode chambers. A power source is electrically coupled to the one or more anodes and the one or more cathodes and configured to apply a current between the one or more anodes and the one or more cathodes. A purging system is configured to introduce one or more of air, O2, and an inert gas to the electrochemical membrane reactor. A pH measurement system is coupled to the electrochemical membrane reactor and an outlet is configured to discharge a purified leaching solution.

[0016] Also disclosed is an electrochemical membrane apparatus comprising an electrochemical membrane reactor comprising one or more anode chambers containing one or more anodes and a cathode chamber containing one or more cathodes. A first ionic exchange membrane is disposed between a first anode chamber of the one or more anode chambers and a second ionic exchange membrane is disposed adjacent the cathode chamber. A first intermediate chamber is between the first ionic exchange membrane and the second ionic exchange membrane. A third ionic exchange membrane is disposed between a second anode chamber of the one or more anode chambers and a fourth ionic exchange membrane is disposed adjacent the cathode chamber. A second intermediate chamber is between the third ionic exchange membrane and the fourth ionic exchange membrane. An inlet is configured to supply a leaching solution to the one or more cathode chambers. A power source is electrically coupled to the one or more anodes and the one or more cathodes and configured to apply a current between the one or more anodes and the one or more cathodes. A purging system is configured to introduce one or more of air. Ch. and an inert gas to the electrochemical membrane reactor. A pH measurement system is coupled to the electrochemical membrane reactor; and an outlet is configured to discharge a purified leaching solution.

[0017] A method of separating elements from a leaching solution using an electrochemical membrane apparatus is also disclosed and includes introducing a leaching solution into an electrochemical membrane reactor. The leaching solution comprises one or more of one or more alkaline metals, one or more alkaline earth metals, one or more actinoids, one or more transition metals, one or more post-transition metals, one or more rare earth metals, one or more metalloids, one or more reactive non-metals. The electrochemical membrane reactor comprises one or more anodes contained in one or more anode chambers. One or more cathodes are contained in one or more cathode chambers adjacent to the one or more anode chambers. At least one ionic exchange membrane is disposed between at least one of the one or more anode chambers and the one or more cathode chambers. An inlet is configured to supply the leaching solution to the one or more cathode chambers. A power source is electrically coupled to the one or more anodes and the one or more cathodes and configured to apply a current between the one or more anodes and the one or more cathodes. A purging system is configured to introduce one or more of air, O2, and an inert gas to the electrochemical membrane reactor. A pH measurement system is coupled to the electrochemical membrane reactor and an outlet is configured to discharge a purified leaching solution. A current is applied between the one or more anodes and the one or more cathodes of the electrochemical membrane reactor to adjust a pH of the leaching solution. One or more of air, O2, and an inert gas to the electrochemical membrane reactor is introduced to the electrochemical membrane reactor. At least one metal from the leaching solution is deposited on the one or more cathodes of the electrochemical membrane reactor. One or more of the one or more transition metals, the one or more posttransition metals, the one or more actinoids, and the one or more rare earth metals is precipitated from the leaching solution and one or more of the one or more transition metals, the one or more post-transition metals, the one or more actinoids, and the one or more rare earth metals, is recovered from the leaching solution. In embodiments of the disclosure, one or more of the deposited metals and precipitated metals is detected by an in- situ spectroscopy system.

[0018] BRIEF DESCRIPTION OF THE DRAWINGS

[0019] For a detailed understanding of the disclosure, reference should be made to the following modes for carrying out the invention, taken in conjunction with the accompanying drawings, in which like elements have generally been designated with like numerals, and wherein:

[0020] FIG. 1 is a side view of an electrochemical membrane reactor in accordance with embodiments of the disclosure.

[0021] FIG. 2 is a side view of an electrochemical membrane reactor in accordance with embodiments of the disclosure.

[0022] FIG. 3 a top-down view of an electrochemical membrane reactor in accordance with embodiments of the disclosure.

[0023] FIG. 4 is a graph showing current (mA) vs. potential (V vs. Hg / Hg2SC>4).

[0024] FIG. 5 is a graph showing current density (mA cm2) vs. potential (V vs. Hg / Hg2SO4).

[0025] FIG. 6 is a graph showing current density (A cm'2) vs. potential (V vs. Hg / Hg2SO4).

[0026] FIG. 7 is a line drawing of a bench-top reactor in accordance with the present disclosure including a coiled nickel foam electrode in a middle cylinder and two nickel plate counter electrodes in two side cylinders.

[0027] FIG. 8 is a line drawing of a coiled nickel foam electrode.

[0028] FIG. 9 is a side view and top-down view of an electrochemical membrane reactor in accordance with embodiments of the disclosure.

[0029] FIG. 10 is a top-down view of an electrochemical membrane reactor in accordance w ith embodiments of the disclosure.

[0030] FIG. 11 is a side view of an electrochemical membrane reactor in accordance with embodiments of the disclosure.

[0031] FIG. 12 is a side view of an electrochemical membrane reactor in accordance with embodiments of the disclosure. FIG. 13 is a top-down view of an electrochemical membrane reactor in accordance with embodiments of the disclosure.

[0032] FIG. 14 is a side view of an electrochemical membrane reactor in accordance with embodiments of the disclosure.

[0033] FIG. 15 is a side view of an electrochemical membrane reactor in accordance with embodiments of the disclosure.

[0034] MODE(S) FOR CARRYING OUT THE INVENTION

[0035] The illustrations presented herein are not actual views of any electrochemical membrane reactor, or any component thereof, but are merely idealized representations, which are employed to describe embodiments of the present invention.

[0036] As used herein, the singular forms following “a,” "‘an,” and '‘the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0037] As used herein, the term “may” with respect to a material, structure, feature, or method act indicates that such is contemplated for use in implementation of an embodiment of the disclosure, and such term is used in preference to the more restrictive term “is” so as to avoid any implication that other compatible materials, structures, features, and methods usable in combination therewith should or must be excluded.

[0038] As used herein, any relational term, such as “first,” “second,” “top,” “bottom,” “upper,” “lower.” “above,” “beneath,” “side,” “upward.” “downward,” etc., is used for clarity and convenience in understanding the disclosure and accompanying drawings, and does not connote or depend on any specific preference or order, except where the context clearly indicates otherwise. For example, these terms may refer to an orientation of elements of any electrochemical reactor when utilized in a conventional manner. Furthermore, these terms may refer to an orientation of elements of any electrochemical membrane reactor as illustrated in the drawings.

[0039] As used herein, the term “substantially” in reference to a given parameter, property7, or condition means and includes to a degree that one skilled in the art would understand that the given parameter, property, or condition is met with a small degree of variance, such as within acceptable manufacturing tolerances. By way of example, depending on the particular parameter, property7, or condition that is substantially met, the parameter, property, or condition may be at least 90.0% met, at least 95.0% met, at least 99.0% met, or even at least 99.9% met. As used herein, the term “about” used in reference to a given parameter is inclusive of the stated value and has the meaning dictated by the context (e.g., it includes the degree of error associated with measurement of the given parameter, as well as variations resulting from manufacturing tolerances, etc.).

[0040] Li-ion batten- recyclers, cathode material producers, and Li-ion battery' manufacturers, among others, have an unmet need for a cost-effective, environmentally sustainable way to recycle spent Li-ion batteries. Idaho National Laboratory (INL) has developed an electrochemical membrane reactor, which may remove impurities from spent LIB to about 1 ppm level without using chemicals, and Ni, Co and Mn recovery efficiency are greater than or equal to 95%. Electrochemical membrane reactors and methods are disclosed that are suitable for removing and recovering chemical elements (e.g., metals) from a leachate obtained from various sources (e.g., feedstocks) including one or more of spent lithium ion batteries, ferromanganese slag, mines (e.g., mining products), mining tailings, mining residue, clay, bauxite, bauxite residue, carbonatite, geothermal brine, coal, or coal ash. The feedstock may be initially processed to form the leachate, which contains the chemical elements in solution. The chemical elements to be recovered may be present in the feedstock at impurity levels or may account for a majority of the feedstock. Depending on the source of the feedstock, its components may already be in solution. The feedstock may, for example, be mechanically processed to produce particles of the feedstock. The feedstock may be milled, such as by using a ball mill or a hammer mill, to reduce the feedstock to smaller particle sizes. Larger particle sizes of the milled feedstock may be removed by, for example, size selection screens. If the milled feedstock is not already in solution, a fluid, such as water, may be combined with the milled feedstock to produce the leachate.

[0041] The chemical element may be recovered as a metal (e.g., an elemental metal) or as a compound of the metal, such as a metal hydroxide compound. The elemental metal or metal compound may be electrodeposited or precipitated, enabling its recovery'. The elemental metal or metal compound may be electrodeposited or precipitated by adjusting one or more conditions within the electrochemical membrane reactor, such as the pH of the leachate within the electrochemical membrane reactor or the current. The pH within the electrochemical membrane reactor may be adjusted by adding an acid or base to the leachate. Alternatively, the pH may be changed by the presence of ions (H+ions, OH" ions) produced during the electrochemical reactions. The elemental metal or metal compound may be electrodeposited or precipitated by changing the pH of the leachate from an acidic pH to a neutral pH, from an acidic pH to a basic pH, from a basic pH to a neutral pH, from a neutral pH to an acidic pH, from a basic pH to an acidic pH, or from a neutral pH to a basic pH. Ions in the leachate may sequentially precipitate as the pH of the leachate changes. By way of example only, Al ions and Fe ions may be removed at a pH between about 2.2 and about 5.3 or rare earth elements may be removed at a pH between about 5.3 and about 10.0.

[0042] The electrochemical membrane reactors and methods according to embodiments of the disclosure reduce chemical consumption for element removal and separation to a minimum, simplify the composition of a purified leaching solution, and generate valuable by-products. The reactors and methods are. therefore, cost-effective and environmentally sustainable. By using the electrochemical membrane reactors and methods according to embodiments of the disclosure to remove impurities from a leaching solution, the cost for recycling may be reduced to about $5 / kg (USD) compared to the $7.5 / kg (USD) cost of conventional methods.

[0043] The electrochemical membrane reactors and methods herein have broad application for chemical element removal and separation. The reactors and methods may be used for recycling spent Li-metal batteries and Li-ion batteries, including removing impurities from a leaching solution prepared from the spent batteries. The reactors and methods may also be used to remove target elements (e.g.. desired chemical elements) from the leachates (e.g., leachates prepared from solid feedstocks) of spent lithium ion batteries, ferromanganese slag, mines (e.g., mining products), mining tailings, mining residue, clay, bauxite, bauxite residue, carbonatite, geothermal brine, used nuclear fuel, coal, or coal ash. In some embodiments, the leaching solution is from a mine product, mine tailing, or a spent Li-ion battery.

[0044] The electrochemical membrane reactors and methods may be employed for separating and removing chemical elements from a waste stream, such as a waste stream prepared from a solid feedstock obtained from lithium ion batteries, ferromanganese slag, mines (e.g., mining products), mining tailings, mining residue, clay, bauxite, bauxite residue, carbonatite, geothermal brine, coal, coal ash, used nuclear fuel, or other sources. The electrochemical reactors and methods may be employed on an industrial scale for recycling, such as for mining and LIB recycling. Bauxite is a naturally occurring, heterogeneous material composed primarily of one or more aluminum hydroxide minerals, plus various mixtures of silica, iron oxide, titania, aluminosilicate, and other impurities in minor or trace amounts. Bauxites are industrially important for both aluminum metal supply and non-metallurgical use and they represent the only raw material used in the production of alumina on a commercial scale. Gallium is a common by-product of aluminum extraction from bauxites, and bauxites may comprise a feedstock for rare earth elements. Carbonatites are igneous rocks formed in the earth’s crust by fractional crystallization of carbonate-rich parental melts that are mostly mantle derived. Carbonatites include carbonate minerals such as calcite, dolomite, and ankerite, as well as minor phosphates, oxides, and silicates. Carbonatites are a source of niobium and rare earth elements, in particular the light rare earth elements, including lanthanum, cerium, praseodymium, and neodymium.

[0045] Electrochemical membrane reactors and methods according to embodiments of the disclosure are provided that are suitable for separating elements (e.g., chemical elements) from mining products and mine tailings including, but not limited to, carbonatite, bauxite, bauxite residue, coal, coal ash. and brine. The electrochemical membrane reactor may be scaled up to a large size, and may be used to separate iron (Fe), aluminum (Al), nickel (Ni), cobalt (Co), lead (Pb), gallium (Ga), rare earth elements, actinoids, and other elements, with high separation efficiencies.

[0046] Electrochemical membrane reactors and methods according to embodiments of the disclosure are provided that are suitable for removing impurities from a leaching solution. The leaching solution may be prepared from a solid feedstock. The leaching solution may comprise one or more of one or more transition metals, one or more post-transition metals, one or more rare earth metals, one or more actinoids, one or more metalloids, one or more alkaline metals, one or more alkaline earth metals, and one or more reactive nonmetals, in water, a liquid containing water, or other liquid. The electrochemical membrane reactors and methods are suitable for removing elements (e.g., metals, metals which may be considered impurities or “low-value” metals) and recovering elements (e g., metals) from solutions prepared from spent waste, such as spent lithium-ion (Li-ion) batteries, ferromanganese slag, mining tailings, mining residue, bauxite, bauxite residue, carbonatite, geothermal brine, used nuclear fuel, coal, or coal ash, although not limited. The reactor may be scaled up to a large size. The reactor and method may remove impurities from spent Li-ion batteries to achieve less than or equal to about 1 ppm level, and may recover greater than about 95% Ni, Co and Mn with a recovery efficiency and industry related time frame.

[0047] The electrochemical membrane reactors and methods may be used in Li-ion battery preparation and recycling. The electrochemical membrane reactor may remove copper, aluminum, iron, zirconium, chromium from the leaching solution prepared from a spent Li- ion battery (e.g., so-called black mass), with the remaining nickel, cobalt and manganese remaining in the solution. Potential customers and users include mining companies, geothermal companies, batteries manufacturing companies, batteries recycling companies, among others. The electrochemical membrane reactor separates and extracts a variety of elements from solution by using electricity, water, and one or more of air, O2, and inert gas (e.g.. argon, nitrogen), and provides the advantages of reduced cost compared to prior methods, such as reduced chemical consumption or no (zero) chemical consumption, environmental benignity, high selectivity, and simplicity due to the process being conducted in a single electrochemical membrane reactor.

[0048] Mines and energy storage systems are composed of or include different elements (e.g.. chemical elements), which may include one or more alkali metals, one or more alkaline earth metals, one or more lanthanoids, one or more actinoids, one or more transition metals, one or more post-transition metals, one or more metalloids, and one or more reactive nonmetals. To efficiently extract and recover valuable elements from the above sources, low-cost, and environmentally sustainable methodologies are desired to selectively extract the various elements. The electrochemical membrane reactor described herein functions to separate and remove desired elements sequentially in the same device (that is, a single electrochemical membrane reactor) consuming only electricity, water, and one or more of air. O2. and inert gas (e.g., argon, nitrogen).

[0049] The electrochemical membrane reactors and methods may be used to recover valuable elements from mines such as one or more of mining waste, mining tailings, and mining residue. Mining tailings may be waste materials left after a target mineral is extracted from ore. Mining residue may be any waste material, or mineral discard, derived from a mining operation. For example, bauxite residue (e.g., red mud) contains elements including iron, aluminum, gallium, titanium, lead, zinc, copper, zirconium, uranium, lead, nickel, silicon, scandium, yttrium and lanthanides. The electrochemical membrane reactor may selectively remove iron, aluminum, gallium, lead, zinc, copper, zirconium, uranium, lead and nickel from the leaching solution of bauxite residue, with scandium, yttrium and lanthanides remaining in the solution, and then may remove scandium, yttrium, and lanthanides in a following stage (e.g., removal act) using the same (e.g., a single) electrochemical membrane reactor.

[0050] The electrochemical membrane reactor and method may separate and remove (e.g., electroplate or precipitate) one or more elements from the feedstock, which may include one or more alkaline earth metals (e.g., beryllium, magnesium, calcium, strontium, barium, and radium), one or more actinoids (e.g., actinium, thorium, protactinium, uranium, neptunium, and plutonium), one or more transition metals (e.g., scandium, yttrium, lutetium (also considered a rare earth element), titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, rhenium, iron, technetium, ruthenium, osmium, cobalt, rhodium, iridium, nickel, palladium, platinum, copper, silver, gold, zinc, cadmium, and mercury), one or more post-transition metals (e.g., gallium, indium, thallium, tin, lead, bismuth, and aluminum), one or more rare earth metals (e.g., cerium, dysprosium, erbium, europium, gadolinium, holmium, lanthanum, lutetium, neodymium, praseodymium, samarium, scandium, terbium, thulium, ytterbium, and yttrium), one or more metalloids (e.g.. boron, silicon, germanium, arsenic, antimony and tellurium), one or more reactive non-metals (e.g., halogen non-metals such as fluorine, chlorine, bromine, iodine, astatine; unclassified non-metals such as carbon and phosphorus; and other reactive non-metals such as sulfur and selenium).

[0051] The electrochemical membrane reactors and methods according to embodiments of the disclosure may be used in a wide variety of applications including, but not limited to, the following:

[0052] The electrochemical membrane reactors and methods may be used in mining recycling to remove transition metals, post-transition metals, such as platinum, copper, aluminum, and iron, lanthanoids, actinoids, scandium, yttrium, cerium, lanthanum, among others, from leaching solutions. The leaching solution may be prepared from mines, mining products, mining tailings, mining residue, and mine slag.

[0053] The electrochemical membrane reactors and methods may be used in lithium extraction from geothermal brine, and to remove impurities, including iron, aluminum, copper, lead, cadmium, chromium, silver, magnesium, manganese, and zinc from brine. These elements (impurities) may interfere with lithium extraction.

[0054] The electrochemical membrane reactors and methods may be used with one or more of carbonatite, bauxite residue, coal, and coal ash as a feedstock for the reactor. Carbonatite, bauxite residue, coal, and coal ash may have from about 1 ppm to about 10,000 ppm of Al and Fe, from about 1 ppm to about 100 ppm of Co and Ni, and from about 1 ppm to about 1000 ppm of rare earth elements. Bauxite deposits may be classified into two main types based on the bedrock lithology: Bauxite deposits overlying aluminosilicate rocks are defined as lateritic bauxites, and bauxite deposits lying on carbonate rocks are identified as karstic bauxites. Gallium concentrations in lateritic bauxites range from below detection (less than about 8 ppm) to about 146 ppm, with the average gallium concentration being about 57 ppm. The average gallium concentration for karstic bauxite deposits is about 58 ppm with a range between less than about 10 ppm to about 180 ppm gallium. As a result, there are no substantial differences in gallium concentrations between karstic- and laterite-type bauxites. The electrochemical membrane reactors and methods according to embodiments of the disclosure may be utilized to separate these elements.

[0055] The electrochemical membrane reactors and methods may be used for rare earth element recycling from spent magnets (e.g., permanent magnets). A permanent magnet is a material where the magnetic field is generated by the internal structure of the matenal itself. Permanent magnets may include a considerable amount of neodymium, such as from about 10 weight percent to about 30 weight percent neodymium of a total mass of the permanent magnet. By way of example only, the magnet may include about 64 weight percent iron, about 23 weight percent neodymium, about 6 weight percent dysprosium, about 3 weight percent cobalt, about 1 weight percent boron, about 1 weight percent praseodymium, about 0.2 weight percent copper, about 0.1 weight percent aluminum, about 0.02 weight percent gadolinium, about 0.02 weight percent nickel, about 0.01 weight percent niobium, and about 0.22 weight percent gallium. A feedstock may be prepared from the magnet (e.g., a magnet at the end of useful life; a spent magnet). The magnet may be demagnetized, such as by sintering, to form a demagnetized magnet. The demagnetized magnet may be ground to form a pow der of the magnet. The magnet powder may be in the micrometer size range to accelerate the electrochemical leaching process. A solution (e.g., leaching solution) may be prepared with the magnet powder and processed in the electrochemical membrane reactor. In an alternate embodiment of the disclosure, the magnet powder may be disposed into an anode container (e.g., an anode forming a container for the magnet powder, also termed an anode bucket). The magnet powder may be contained in the anode container and processed in the electrochemical membrane reactor. In embodiments of the disclosure, the anode comprises a titanium container which functions as the anode of the electrochemical membrane reactor. The electrochemical membrane reactor may be used to remove one or more of copper, aluminum, iron, gallium, nickel and cobalt from the leaching solution first, with any neodymium, gadolinium, dysprosium, and praseodymium remaining in the solution. These rare earth elements may be precipitated out in the next stage (e.g., a next process or act) in the reactor. For example, the magnet feedstock (e.g., the leaching solution or the magnet powder) may be processed in the electrochemical membrane reactor to electrodeposit one or more of copper, nickel, and iron metals on to the cathode, to precipitate one or more of aluminum hydroxide (A1(OH4)) and iron hydroxide (Fe(OH)3), leaving one or more of neodymium, praseodymium, and dysprosium ions in solution. One or more of neodymium, praseodymium, and dysprosium may then be recovered from the solution as metal or their hydroxides.

[0056] The electrochemical membrane reactors and methods may be used for recycling of used nuclear fuel. The electrochemical membrane reactor may remove one or more of antimony (Sb), selenium (Se). tin (Sn), technetium (Tc), ruthenium (Ru). tellurium (Te). and a portion of molybdenum (Mo) from the leaching solution first (e g., in a first stage or step in the reactor), remove uranium (U), plutonium (Pu), and zirconium (Zr) in a second stage in the reactor, and remove lanthanide, and yttrium (Y) in a third stage in the reactor. Uranium may be separated from a mixture comprising uranium, plutonium, and zirconium hydroxides by oxidizing O2 in the used nuclear fuel to UO2by the reactor in a fourth stage (e.g., a fourth process or step).

[0057] In embodiments of the disclosure, an electrochemical membrane apparatus is disclosed comprising an electrochemical membrane reactor comprising one or more anodes contained in one or more anode chambers. One or more cathodes are contained in one or more cathode chambers adjacent to the one or more anode chambers. At least one ionic exchange membrane is disposed between at least one of the one or more anode chambers and the one or more cathode chambers. An inlet is configured to supply a leaching solution to the one or more cathode chambers. A power source is electrically coupled to the one or more anodes and the one or more cathodes and configured to apply a current between the one or more anodes and the one or more cathodes. A purging system is configured to introduce one or more of air, O2, and an inert gas to the electrochemical membrane reactor. A pH measurement system is coupled to the electrochemical membrane reactor and an outlet is configured to discharge a purified leaching solution. A spectroscopy system, in embodiments a Fourier Transform Infrared Spectroscopy (FTIR) may be coupled to the electrochemical membrane reactor (e.g., the cathode) to detect separated products (e.g., elements, metals).

[0058] A system 100 including an electrochemical membrane reactor 110 is shown in FIG. 1. The electrochemical membrane reactor 110 includes anodes 114 in anode chambers 116 and cathodes 118 in a cathode chamber 120. A leaching solution 112 (e.g., a leachate to be treated) is flowed through the electrochemical membrane reactor 1 10 by circulation pump 126a. The anodes 114 in the anode chambers 116 are disposed on opposite sides of the cathode 118 in the cathode chamber 120. Ionic exchange membrane 122 (e.g.. an anionic exchange membrane) separates the anode chamber 116 and the cathode chamber 120. Inlet 124 (e.g., an air / Ch / inert gas inlet) is present in the cathode chamber 120 for purging a gas (e.g., air / Ch) into the cathode chamber 120. Filter 128 is operatively coupled to the circulation pump 126b to remove precipitates from the leaching solution during electrolysis. A potentiostat 130 for supplying power to the anode 114 and cathode 118 is connected to the anode 114 and cathode 118. A pH probe 132 and pH controller 134 are provided to measure and adjust the pH of the system 100. The pH probe 132 and pH controller 134 may be employed to determine the appropriate time of electrolysis halt. A vessel 138 may be operatively coupled to the filter 128 to recover a purified leachate that exits the electrochemical membrane reactor 110. Anode chamber 116 contains an electrolyte (e.g., a salt solution).

[0059] To process a large amount of leaching solution, the dimensions of the electrochemical membrane reactor may be large, and may include a specific configuration, including, but not limited to. the following aspects.

[0060] The electrochemical membrane reactor may be configured to have a large size to accommodate the arrangement of anode(s) and ionic exchange membranes, such as one or more cationic exchange membranes, anionic exchange membranes, and bipolar membranes.

[0061] The working electrode may be selected depending on the material composition of the feedstock and the elements to be recovered from the leaching solution. In embodiments of the disclosure, a plate electrode may be used for electroplating stages (e.g., acts) and a porous electrode may be used for precipitating stages (e.g., acts). By w ay of example, for a leaching solution prepared from a used lithium ion battery, a plate electrode may be used for electroplating one or more elements from the leaching solution and a porous electrode may be used for precipitating one or more elements from the leaching solution. The working electrode may be made from one or more of nickel, copper, iron, titanium, aluminum, stainless steel, and carbon, and may be configured as a plate electrode, a mesh electrode, or a foam electrode. In embodiments of the disclosure, the one or more cathodes comprise one or more of a nickel mesh, a nickel foam, a nickel plate, a copper mesh, a copper foam, a copper plate, a stainless steel mesh, a stainless steel foam, a stainless steel plate, a titanium mesh, a titanium foam, and a titanium plate, a carbon mesh, a carbon foam, and a carbon plate. The counter electrode (plate electrode) may be formed of active metals, such as nickel, iron, lead, zinc, titanium, aluminum, cobalt, and tin, or by noble metals, such as platinum, iridium oxide, titanium coated with ruthenium oxide, or titanium coated with iridium oxide. The chamber, where the working electrode is located, has the geothermal brine, or leaching solution from mine, mine slag, mine waste, Li-ion batteries and Li-metal batteries charged (e.g., poured) therein. If it is necessary7, air, oxygen, or an inert gas may be purged into the chamber. The anode chamber, where the counter electrode is located, has a salt solution as an electrolyte, which may be one or more of Na2SO4, K2SO4, Na2CO3, K2CO3, CaSO4, NaCl, KC1, CaCl2, NaC104, KC1O4, Ca(C104)2, Na3PO4, and KaPO4charged (e.g., poured) therein. The electrochemical membrane reactor extracts elements from the above solutions through two reaction mechanisms: the electroplating mechanism, by which one or more of, for example, Pt. Ag. Cu, Cd, Pb and Zn are extracted; as the electroplating potentials of these elements are above or near to the H2evolution potential; and the electrochemical precipitation mechanism, where H2O and O2are reduced to OH" ions (and H2), and the pH value of the solution is increased. The generated OH’ ions precipitate, for example, one or more of Al. Fe. Zn. Mn, U, Ga, V, Zr, Cr, Sc, Y, lanthanides and Mg. When elements electroplate, H2O and O2are reduced on the working electrode. The anode, when comprising an active material, dissolves into the electrolyte at the same time. For example, when an anode comprising nickel is used, the nickel anode is oxidized to Ni2+ions, which dissolve into the electrolyte. After elements’ extraction from brine, or the leaching solution, the solution in the working electrode chamber may be replaced with an electrolyte solution, such as one or more of Na2SO4, K2SO4, Na2CO3, K2CO3, CaSO4, NaCl, KC1, CaCl2, NaC104, KC1O4, Ca(C104)2, Na3PO4, and KSPO4, and the polarity of the reactor may be switched. The dissolved anode metal ions may be electroplated back to the anode and acid is generated on the other electrode. The anode may be made of noble metal, which does not dissolve into electrolyte but oxidizes H2O to produce H+ions and O2, during the process of elements extraction.

[0062] A large size reactor may be provided to increase the dimension of the cathode(s) (e.g., one or more porous cathodes, one or more cathode plates, one or more mesh cathodes, or one or more foam cathodes) and to maintain a short processing time. Using a larger cathode increases the distance of ions’ transmission, leading to a wider potential distribution on the cathode. The reactor configuration design may mitigate the voltage drop on the cathode side. Anode plates and ionic exchange membranes are arranged around and in the middle of the porous cathode plate(s) to eliminate the voltage drop and ensure uniform potential distribution on the cathode.

[0063] For a given reactor size and shape, the dimension of the porous cathode and the potential distribution across the cathode may be modified. In embodiments, the porous cathode matrix comprises multi-layers of metal meshes or foams (such as nickel mesh / foam, copper mesh / foam, stainless steel mesh / foam, carbon foam, and titanium mesh / foam), and the matrix may be assembled and dissembled layer by layer, facilitating cleaning of the electrode. The large size reactor may desirably possess a higher mechanical strength than a reactor utilizing a smaller size cathode, as the flowing leachate contacts the cathode. In embodiments, each cathode layer includes a frame (e.g., a support) for the purpose of consolidating the electrode layer. To fully utilize the electrode surface and keep the cathode potential distribution in a certain potential window, one or more of the porosity and pore size of the cathode layer are adjusted from the outside (e.g., external surfaces) to the inside (e.g., interior surfaces). The pore size may be in a range from millimeter to micrometer size. To balance the two factors of fully utilizing the electrode / electrolyte interface and narrowing potential distribution, one or more of the pore size of the outside cathode layer(s) may or may not be larger than one or more of the pore size of the inside cathode layer(s).

[0064] The electrochemical membrane reactor may include a leachate flowing system, an air / 02 / inert gas purging system, a pH measurement system, an in-situ product detection system (e.g.. Fourier Transform Infrared, FTIR), and a digital control system. In embodiments of the disclosure, one or more of these systems may be included in a large size reactor.

[0065] In embodiments, the reactor comprises anode plates and anion exchange membranes around and in the middle of the porous cathode. In such embodiments, there may not be sufficient space to accommodate a mechanical stirring system in the reactor, and a water circulation pumping system is provided to circulate the leachate, ensuring uniform pH distribution. When one or more impurities are removed (e.g., precipitated), the solid phase may affect the following O2 reduction reaction, and a filter connected with a circulation pump is provided to remove precipitates from the leaching solution during the electrolysis. A pH probe may monitor the pH change of the leachate and a pH meter may send a signal to a digital control system, which may control an on / off switch of one or more of the circulation pumps, one or more motor and pulley systems for inserting and removing the working electrodes, and the sparging of gas, such as air / Ch / inert gas. The in-situ product detection system may detect the electroplated and / or precipitated products, sending a signal to the digital control system. An air / Ch / inert gas purging system with multiple purging tubes may be provided to supply adequate air / Ch / inert gas for large current electrolysis or supply adequate inert gas to protect the generated products. The system may also include a pH measurement sy stem and a pH controller to automatically determine the appropriate time of electrolysis halt.

[0066] Reaction mechanisms for impurity removal and element separation by the electrochemical membrane reactor and method are shown in Table 1 to Table 5 for leaching solutions prepared from feedstocks including spent lithium ion batteries, carbonatite, spent magnets, bauxite residue, and used nuclear fuel, respectively. The method of impurity removal and element separation may be divided into stages (e.g., process steps), such as two or more stages, depending on the composition of the feedstock and the leaching solution prepared therefrom.

[0067] In embodiments of the disclosure, the anode comprises an active metal. In other embodiments of the disclosure, the anode is inert (e.g., the anode comprises an inert metal). The anode may be formed of and include one or more of graphite, copper, iron, titanium, lead, tin, cobalt, and nickel. Alternatively, the anode may be formed of and include an inert metal. In embodiments, the anode comprises one or more of platinum, gold, ruthenium oxide, iridium oxide, titanium, ruthenium oxide coated titanium, and iridium oxide coated titanium. In embodiments of the disclosure, the anode comprises one or more inert metals such as platinum, titanium, titanium coated with ruthenium, gold, or iridium.

[0068] During the electrochemical membrane reactor’s operation for element separation, a gas, such as one or more of O2, air and an inert gas (e.g., nitrogen, argon), may be optionally introduced (e.g., sparged) into the reactor in the different separation stages. For example, in the process of purifying a leachate obtained from spent lithium ion batteries, in a first stage (stage 1), no gas is introduced into the cathode chamber including a cathode of the electrochemical membrane reactor and the pH of the leaching solution inside the cathode chamber is increased to about 4 by the H+ions’ reduction reaction. In the meantime, Cu2+ions are electroplated as Cu metal and Fe3+ions are reduced to Fe2+ions. In a second stage (stage 2), air / Ch is purged into the leachate to produce OH’ ions, that precipitate Fe3+. Al3+, Zr4+and Cr3ions, based on their pH-potential diagram. Fe2+ions are oxidized to Fe2O3, Fe3O4 and Fe(OH)3 compounds by the O2. The anodic reaction inside the electrochemical membrane reactor depends on the material of the anode. The reactive metal anode may be one or more of lead, nickel, cobalt, iron, copper, and zinc. If the anode is an active metal (e g., a reactive metal), such as Ni metal, the Ni oxidation reaction is the dominant reaction. If an inert metal is used as the anode material, H2O oxidation occurs. The constant current passing through the reactor is different in stage 1 and stage 2, and the potentials of Ni and Co electroplating reactions limit the current value of stage 2. When the pH of the leachate is increased above about 5.2, electrolysis and air / 02 purging is halted, and the leachate is filtered to capture the precipitates, including Fe2O3, Fe3O4, Fe(OH)3, A1(OH)3, Zr(OH)4and Cr(OH)3.

[0069] In embodiments of the disclosure, the electrochemical membrane reactor may be used to separate elements from a solution prepared with bauxite or bauxite residue as the feedstock. In the first stage. Fe3+ions are reduced to Fe2+ions and protons are reduced to H2, increasing the pH of the solution. No gas sparging is used in the first stage. In the second stage, Fe, Ni, Zn and Pb gradually electroplate out in metallic form, depositing on the surface of electrode. In the third stage, Al3+, Zr4+and Cr3+ions are precipitated out as hydroxide compounds. To avoid oxidation of Fe2+ions to Fe3+ions by air in the third stage, and Fe3+10ns precipitation as Fe OH)?. which can mix with other precipitates, an inert gas, such as nitrogen gas and argon, may be sparged into the leachate in the third stage. In the fourth stage, the remaining Fe2+ions are oxidized to Fe3+ions by the electrochemical membrane reactor and then precipitated out. In the fifth stage, scandium, yttrium, and lanthanides are precipitated out. From stage 3 to stage 5, no gas is used to sparge the leachate.

[0070] In embodiments of the disclosure, the anode comprises an active metal. When the anode comprises an active metal, an additional stage may be performed for reactor restoration comprising introducing an electrolyte solution into one or more cathode chambers and reversing polarity of the electrochemical membrane reactor to electroplate dissolved reactive anode metal ions back onto the one or more reactive metal anodes. For example, where the anode comprises an active metal, the process may further comprise a reactor restoration stage. After discharge of the processed leachate, an electrolyte, such as Na2SC>4 solution (about 0.2 mol l’1), may be introduced (e.g., flushed) into the cathode chamber, and the polarity of the electrochemical cell switched. The dissolved active metal ions may be electroplated back to the original anode plate, or the oxidized active metal ions may be reduced back to metallic form, and FT ions and O2 may be generated in the original cathode chamber.

[0071] In other embodiments of the disclosure, the anode is inert (e.g., the anode comprises an inert metal). In embodiments where the anode is fabricated from an inert metal, H+ions and O2 may be generated inside the anode chamber (in early stages such as in stage 1 and 2), reducing or eliminating the need for a reactor restoration.

[0072] When processing the leachate of spent lithium ion batteries, the reactor may achieve a recovery efficiency of about 95% of Ni, Co and Mn, about 5 ppm of each impurity, and less than about 15 hours of processing time. The cunent density of the porous electrode may be no less than about 0.25 mA- cm’3, inside the leaching solution at a pH of about 4. The ionic conductivity of the leaching solution may be about 4 S cm1; the potential window for the desired electrochemical reaction in stage 2 may be under about 0.35 V and the porosity of a porous electrode (e.g., porous cathode) may be about 80% to about 90%. When setting up the anode in the middle of the reactor, the width of the reactor (excluding the width of the middle and outside anode chamber), may be as large as about 2.016 meters and potential distribution on the cathode may be under about 0.35 V. The design of the length and the depth of the reactor may be more flexible, and their values may depend on the material selected for the cathode, membrane, and anode. The reactor, configured as provided herein, is capable of scale up to industrial quantities.

[0073] A system 200 including a relatively large-size electrochemical membrane reactor 210 is shown in FIG. 2. Anodes 214 include anode plates 214 in the middle and around a multi-layer porous cathode 218. Anode chamber 216 and cathode chamber 220 are defined by anodes 214 and cathodes 218. An ionic exchange membrane 222 is disposed between the anode chamber 216 and the cathode chamber 220. An air / Ch / inert gas purge inlet 224 (e.g., a tube) is included for charging air, O2, or other gas into the electrochemical membrane reactor 210. Circulation pumps 226a and 226b are provided to circulate the leachate. Filter 228 is connected to one or more of circulation pumps 226a, 226b to remove precipitates from the leaching solution during the electrolysis. A potentiostat 230 for supplying power to the anodes 214 and cathode 218 is connected to the anodes 214 and cathode 218. A pH probe 232 and pH controller 234 are provided to measure and adjust the pH of the system 200. A product container 238 may be connected to the filter 228 to contain a purified leachate. The system 200 may include materials and components as described above for FIG. 1.

[0074] FIG. 3 shows a top-down view of system 300 including an embodiment of a large- size electrochemical membrane reactor 310. In FIG. 3, anodes 314 (e.g., anode plates) surround the cathode electrode 318 and are also in the middle of the cathode electrode 318. The cathode electrode 318 may include multiple cathode layers, such as outer cathode layers 318a and inner cathode layers 318b. The cathode may exhibit a variable porosity (e.g., variable pore size) such as a variable porosity (e.g., variable pore size) across a thickness of the one or more cathode layers. The cathode may exhibit a variable porosity' (e.g., variable pore size) wherein the porosity (e.g., pore size) of an outer portion of the cathode is larger than the porosity (e.g.. pore size) of an inner portion of the cathode. In embodiments of the disclosure, an outer portion of the cathode exhibits a pore size that is different from the pore size of an inner portion of the cathode. In embodiments, outer cathode layers 318a have a first size and inner cathode layers 318b have a second pore size that is different from the first pore size of the outer cathode layers 318a. Anode chamber 316 and cathode chamber 320 are defined by the anodes 314 and cathodes 318, respectively. An ionic exchange membrane 322 is disposed between an outer anode chamber 316 and the cathode chamber 320 and between an inner anode chamber 316 and the cathode chamber 320. An air / 02 / inert gas purge inlet 324 (e.g.. a tube) is included for charging air, O2, or other gas into the electrochemical membrane reactor 310. Circulation pumps 326a and 326b are provided to circulate the leachate, as indicated by arrows. The leachate 313 may flow in the direction of the arrows with dotted lines during the flow through the electrochemical membrane reactor 310. Filter 328 is operatively coupled to one or more of circulation pumps 326a, 326b to remove precipitates from the leaching solution during the electrolysis. A product container 338 may be connected to the filter 328 to contain a purified leachate. The system 300 may include materials and components as described above for FIG. 1. Advantages of the electrochemical membrane reactor 110, 210, 310 and method include, but are not limited to, no, or essentially no. reagent depletion, or less reagent depletion as compared to conventional methods, and net zero emission for the purification and removal of elements, such as valuable elements such as Ni, Co, Mn, and rare earth elements, and reducing the cost as compared to conventional methods. The electrochemical membrane reactor may remove impurities from a leaching solution by both precipitation and electroplating processes while only consuming electricity, air and water. The method may also reduce the cost by reduced reagent consumption as compared with conventional methods. The electricity used may include that produced by hydroelectricity and the process may, therefore, provide net zero emission of greenhouse gas (GHG). By comparison, methods based on chemical precipitation may give rise to GHG emissions during the reagent fabrication process.

[0075] In embodiments, the electrochemical membrane reactor 1 10, 210, 310 and method are used for treating the leachate of spent lithium ion batteries and enable the removal of five impurities and pH adjustment in one reactor during one or more stages conducted in the reactor. The reactor adjusts the leachate from a low pH to a moderate pH value, removes Cu by electroplating, and removes Al, Fe, Zr and Cr by selective precipitation. All of these reactions may occur in one process and in a single electrochemical membrane reactor 110, 210. 310. Impurity removal in one process not only simplifies the operation procedure, but also increases the recovery efficiency of Ni, Co and Mn, in comparison with prior chemical purification and solvent extraction methods, which include multiple scrubbing and stripping acts, lowering the recovery efficiency.

[0076] In embodiments, the electrochemical membrane reactor 110, 210, 310 and method provide excellent impurity removal (greater than about 10’5mol I1) and high Co, Ni recovery efficiency (about 95%) for recycling spent lithium ion batteries. Conventional chemical precipitation methods remove impurities by using one reaction mechanism. Because of the close solubility value (Ksp) of Cu(OH)2, Ni(OH)2 and Co(OH)2, a portion of the Ni and Co are removed together with Cu using the conventional chemical precipitation methods. In contrast, the electrochemical membrane reactor 110. 210, 310 and method according to embodiments of the disclosure remove Cu by electroplating, and removes Fe, Al, Zr and Cr by precipitation. Therefore, the electrochemical membrane reactor 110, 210, 310 and method do not have the issue of the trade-off between substantially complete impurity removal and high Ni, Co recovery efficiency, as conventional chemical precipitation-based processes have.

[0077] In embodiments, the electrochemical membrane reactor 1 10, 210, 310 and method may provide superior selectivity by electrochemical precipitation as compared to chemical precipitation. Chemical precipitation may have the disadvantage of poor selectivity for element separation. When NaOH solution is added into the leachate, the incoming reagent induces a high localized pH value for a short period of time because of the limited diffusion and convection rate of the reagent. The phenomenon affects the element’s selectivity and lowers element recovery' and / or extraction efficiency for one or more of nickel, cobalt, and rare earth elements. In contrast, the electrochemical membrane reactor 110, 210, 310 and method according to embodiments of the disclosure generate OH" ions on the electrode / electrolyte interface, and the OH" ions’ distribution is scattered by the large surface area of the porous electrode. Therefore, the electrochemical precipitation may have a more even (e.g., more uniform) pH distribution and better selectivity for impurity removal.

[0078] The electrochemical membrane reactor 110. 210, 310 and method may further provide economic efficiency enhancement by generating valuable by-products. The electrochemical membrane reactor removes impurity from leachate, and generates H2SO4 as by-product, which may be reused to leach black mass, cutting down the recycling cost.

[0079] The electrochemical membrane reactor 110. 210, 310 and method further provide impurity removal without introducing extra impurity into the process, mitigating waste emission. The electrochemical membrane reactor 110, 210, 310 removes impurities (e.g., “low-value” metals) and extracts elements (e.g.. metals) using electricity, water, and one or more of air, O2, and inert gas (e.g., nitrogen, argon) and the process does not introduce extra impurities as chemical precipitation does. In embodiments comprising recycling of spent lithium ion batteries, lithium is recovered from the battery first, a leachate is prepared from the battery's so-called black mass after the recovered lithium is removed from the black mass, and the purified leachate processed with the electrochemical membrane reactor 110, 210. 310 and method has the same composition as a mixed solution prepared from commercial chemicals. The simplified solution mitigates waste emissions. High efficiency of lithium recovery simplifies the method. The lithium roasting technology enables high recovery of lithium while simplifying the method. In conventional solvent extraction, Ni must be extracted from the remaining lithium. In the solvent extraction process, residual sodium in solution from the multi-step extractions limits the lithium recovery efficiency to about 80% due to the solubility of sodium sulfate versus lithium carbonate. The result is the need for another extraction and more sodium sulfate produced. In the method according to embodiments of the disclosure, by having a high purity metal sulfate solution containing substantially no lithium, the number of extractions conducted may be reduced to produce metal sulfate salts. In embodiments of the disclosure, extraction steps to produce metal sulfate salts may be reduced by half as compared to conventional methods. In embodiments of the disclosure, metal sulfate salts may be produced with a single (one) extraction step or with a two-step extraction for separating NiSCfi, CoSO4 and MnSCh from purified leachate.

[0080] For the electrochemical membrane reactor 110, 210, 310 and method according to embodiments of the disclosure, both input streams (e.g., leaching solution, leachate, brine, etc.) and output products are flexible. The electrochemical membrane reactor 110, 210, 310 and method enable processing of different kinds of spent lithium ion batteries, and the concentrations of nickel, manganese, and cobalt in the recovered precursor and cathode material may be specifically tailored to match market needs. Additionally, a wide variety of LiNixMnyCozCh compounds may be synthesized from the recovered nickel, manganese, and cobalt, by adding metal sulfates to the purified leachate liquor to establish the desired compositions, so that the desired NixMnyCoz(OH)2 may be precipitated, from which LiNixMnyCozO2 may be synthesized, based on industrial needs. In embodiments, x, y. and z may each be 1. The electrochemical membrane reactor 110, 210, 310 and method herein provide the ability to tailor the ratio of Ni, Mn, and Co to a desired stoichiometry' (NMC111 / 532 / 622 / 811, etc.), enhancing the utility and commercial prospects. NMC indicates the relative stoichiometry of the three metals nickel, manganese, and cobalt. For example, an NMC molar composition of about 33% nickel, about 33% manganese, and about 33% cobalt would abbreviate to NMC111 (or NMC333 or NCM333) and have a chemical formula of LiNio.33Mno.33Coo.33O2. An NMC composition of about 50% nickel, about 30% manganese, and about 20% cobalt would be called NMC532 (or NCM523) and have the formula LiNio.5Mno.3Coo.2O2. Other compositions of NMC are NMC622 and NMC8 11. The general lithium content may remain around 1 : 1 with the total transition metal content, with commercial NMC samples usually containing less than about 5% excess lithium. In embodiments where the leachate comprises one or more of Cu. Fe, Al, Zr, Cr, Ni, Co. and Mn, the electrochemical membrane reactors and methods herein use just electricity, water, and one or more of air, O2, and inert gas, to remove Cu, Fe, Al, Zr, and Cr in one process. The impurity removal is thorough, and Ni, Co, Mn recovery efficiency may be greater than or equal to about 95%. The electrochemical membrane reactor 110, 210. 310 and method may substantially eliminate waste emission. The electrochemical membrane reactor 110, 210, 310 uses the least amount of additional chemicals to recycle substantially all of the valuable elements, including Li, Ni, Mn and Co, and substantially all of the by-products generated from each step, which may be reused in the electrochemical membrane reactor / method. The method significantly reduces waste emission.

[0081] The electrochemical membrane reactor 110, 210, 310 and method may remove copper, iron, and aluminum impurity to about 1 ppm level from the leaching solution. No additional impurity is introduced and the method consumes only electricity, water, and one or more of air, O2, and inert gas. About 94.5% of Ni, about 97.7% of Co, and about 99% of Mn may be recovered by the electrochemical membrane reactor 110, 210. 310 and the charge utilization rate for the reactor to remove impurity may be about 92.5%.

[0082] In embodiments of the disclosure, the electrochemical membrane reactor includes w orking electrodes (one or more porous electrodes, plate electrodes), a counter electrode, and a membrane between the working electrode and the counter electrode. Geothermal brine contains chloride ions, which mine, mine waste, mine slag, Li metal batteries and Li- ion batteries do not include. Therefore, embodiments of the disclosure contemplate differences in the reactor for element extraction from geothermal brine and other applications, such as mining, mine slag and waste process, Li-ion batteries and Li-metal batteries recycling. The electrochemical membrane reactor may include one kind of membrane, such as an anion exchange membrane, sandwiched between the working electrode and the counter electrode, as shown in FIG. 1, FIG. 2, FIG. 3, FIG. 9, and FIG. 10.

[0083] FIG. 9 shows a side view and a top-down view of a system 400 including an electrochemical membrane reactor 410. Anodes 414 in an anode chamber 416 are disposed around a porous cathode 418 in a cathode chamber 420. Ionic exchange membrane 422 (e.g., anionic exchange membrane) separates the anode chamber 416 and the cathode chamber 420. Inlet 424 (e.g., air / 02 / inert gas inlet) is connected to the cathode chamber 420 for purging a gas (e.g., air / Ch) into the cathode chamber 420. A mechanical stirrer 440 may be disposed in the cathode chamber 420 to circulate the leachate through the electrochemical membrane reactor 410.

[0084] FIG. 10 shows a top-down view of a system 500 including an electrochemical membrane reactor 510. In FIG. 10, a flowing leachate 513 may flow in the direction of the arrow during the passage through the electrochemical membrane reactor 510. Anodes 514 (e.g.. anode plates) surround and are in the middle of the cathode electrode 518. Anode chamber 516 and cathode chamber 520 are defined by the anodes 514 and the cathodes 518. An ionic exchange membrane 522 is disposed between the anode chamber 516 and the cathode chamber 520. An air / Ch / inert gas purge inlet 524 (e.g., a tube) is included for charging air, O2, or other gas (e.g.. argon, nitrogen) into the electrochemical membrane reactor 510.

[0085] The reactors, such as the reactors shown in FIG. 1, FIG. 9, and FIG. 10, may be used for elements’ extraction from mine slag and mine waste. For example, feedstock from a cobaltite mine in Idaho has elements, including Co, Cu, Fe, As, S, Ni, Al. The reactor in FIGS. 1. 9. or 10 may remove Cu. Fe and Al from the leaching solution, enriching Co. Ni. As and S in the leaching solution. Bauxite residue is the mining waste after extracting aluminum from bauxite. Bauxite residue (e.g., red mud) has as its main components AI2O3, Fe2C>3, SiCh, TiCh, CaO, Na2O, and CaCCh. Minor elements include U, Ga, V, Zr. Sc, Cr, Mn, Y. Ni. Zn. Cu, Pb, lanthanides, and Th. The reactor in FIGS. 1, 9. or 10 may extract Al, Fe, U, Ga, V, Zr, Ni, Zn, Cu and Pb first, and then extract Sc, Y and lanthanides later.

[0086] Geothermal brine has a high concentration of chloride ions. When the working electrode extracts relevant elements from brine, chloride ions may transmit through the membrane and go to the counter electrode side, which oxidizes chloride ions to chloride gas, according to the equation: 2CF — > Ch + 2e’. Chloride ions may corrode the anode material and the generated chloride gas may corrode equipment. To reduce the corrosion, the counter electrode may be made of Ag, which may combine with the transmitting Cl" ions to form AgCl. according to the equation: Ag + C1‘ AgCl + e'. The drawback may also be overcome by the reactor designs according to embodiments of the disclosure wherein the electrochemical membrane reactor includes two kinds of membranes which may be sandwiched between a working electrode and a counter electrode. For example, the electrochemical membrane reactor may include two ion exchange membranes disposed between the porous cathode (e.g., cathode plate or plates) and the counter electrode (e.g., one or more anode plates) such that the two ion exchange membranes form an intermediate chamber between a cathode chamber and an anode chamber through which electrolyte may pass. The ion exchange membranes may be one or more of an anion exchange membrane, a cation exchange membrane, and a bipolar membrane.

[0087] A system 600 including an electrochemical membrane reactor 610 including two kinds of membranes is shown in FIG. 11. A feed stream 612 (e.g., brine) is introduced (e.g.. charged, poured) into cathode chamber 620 (e.g., chamber 1). Anodes 614 are disposed around the porous cathode 618 forming anode chambers 616 and intermediate chambers 617. Anionic exchange membranes 622 separate the cathode chamber 620 (e.g., chamber 1) from the intermediate chamber 617 (e.g., chamber 2). Cationic exchange membranes 623 separate the anode chamber 617 (e.g., chamber 2) from the intermediate chamber 616 (e.g., chamber 3).

[0088] The electrochemical membrane reactor 610 shown in FIG. 11 includes three chambers: chamber 1 (e.g., cathode chamber 620), chamber 2 (e.g., electrode chamber 617), and chamber 3 (e.g., intermediate chamber 616). The working electrode 618 comprises one or more of a mesh cathode, a foam cathode, and a plate cathode, such as a three-dimensional Metal Frame Porous Cathode (MFPC). The counter electrode 614 (e.g., anode) comprises an active metal or an inert metal. The anion exchange membrane 622 (AEM) is between chambers 1 and 2, and the cation exchange membrane 623 (CEM) is between chambers 2 and 3. The brine 612 is introduced (e.g., poured) into chamber 1. A dilute NaCl solution (e.g., about 2% to about 10% aqueous solution NaCl) may flow through chamber 2, and a Na2SC>4 solution may flow through chamber 3 as shown by the arrows. When the anode 614 oxidizes H2O to produce H+ions and O2, Na+ions travel from chamber 3 to chamber 2 through the CEM 623 and combine with Cl" ions, which transmit from chamber 1 to form NaCl. Purified brine 636 exits the cathode chamber 620 and may be collected in a container (not shown).

[0089] FIG. 12 show s a system 700 including an electrochemical membrane reactor 710 including a similar configuration as the electrochemical membrane reactor 610 shown in FIG. 11, but including a bipolar membrane 723 (BPM) instead of the CEM 623. A feed stream 712 (e.g., brine) is introduced (e.g., charged, poured) into cathode chamber 720 (e.g., chamber 1). Anodes 714 are disposed around the porous cathode 718 forming anode chambers 716 and intermediate chamber 717. Anionic exchange membranes 722 separate the cathode chamber 720 (e.g., chamber 1) from the intermediate chamber 717 (e.g., chamber 2). Bipolar membranes 723 separate the intermediate chamber 717 (e.g., chamber 2) from the anode chamber 716 (e.g., chamber 3). Similar to the electrochemical membrane reactor 610 shown in FIG. 11, the electrochemical membrane reactor 710 includes three chambers: chamber 1 (e.g., cathode chamber 720), chamber 2 (e.g., intermediate chamber 717), and chamber 3 (e.g., anode chamber 716). Working electrode 718 (e.g., three-dimensional Metal Frame Porous Cathode (MFPC)) comprises one or more of a mesh cathode, a foam cathode, and a plate cathode. The counter electrode 714 (e.g., anode) comprises an inert metal. The anion exchange membrane 722 (AEM) is sandwiched between chambers 1 and 2, and the bipolar membrane 723 (BPM) is sandwiched between chambers 2 and 3. The brine 712 is introduced (e.g., poured) into chamber 1. A dilute NaCl solution (e.g., about 2% to about 10% aqueous solution NaCl) may flow through chamber 2, and Na2SC>4 solution may flow through chamber 3 as shown by the arrows. When the anode 714 oxidizes H2O to produce H+ions and O2, Na+ions travel from chamber 3 to chamber 2 through the BPM 723 and combine with Cl" ions, which transmit from chamber 1 to form NaCl. Purified brine 736 exits the cathode chamber 720 and may be collected in a container (not shown). The electrochemical membrane reactor 710 may be used to extract all of the elements as the electrochemical membrane reactor 610 shown in FIG. 11 and generates HC1 as a byproduct.

[0090] FIG. 13 is a top-down view7of a system 800 including an electrochemical membrane reactor 810. The electrochemical membrane reactor 810 is similar to the electrochemical membrane reactors 610 and 710 shown in FIG. 11 and FIG. 12, respectively. Electrochemical membrane reactor 810 includes anodes 814, anode chamber 816, intermediate chamber 817, cathode 818, and cathode chamber 820. Ionic exchange membrane 822 separates the anode chamber 817 from the cathode chamber 820. A tube 824 is provided for purging a gas (e.g., air, O2, nitrogen, argon) into the electrochemical membrane reactor 810. A stirrer 840 (e.g., mechanical stirrer) is disposed in cathode chamber 820 to circulate the leachate through the electrochemical membrane reactor 810.

[0091] FIG. 14 shows a system 900 including an electrochemical membrane reactor 910 integrated with one or more digital control systems. The electrochemical membrane reactor 910 includes a feed source (e.g., leachate, leaching solution, brine) 912 from which a flowing leachate 913 may enter the electrochemical membrane reactor 910. A circulation pump 926 is provided to circulate the leachate 913. The electrochemical membrane reactor 910 includes anodes 914, anode chamber 916, cathodes 918, and cathode chamber 920. The cathode 918 may be disposed into and removed from the cathode chamber such as by a pulley system including a motor 948. Ionic exchange membrane 922 separates the anode chamber 916 from the cathode chamber 920. An air / Ch / inert gas purge inlet 924 (e.g., a tube) is included for charging air, O2, or other gas (e.g., argon, nitrogen) into the electrochemical membrane reactor 910. A filter 928 is connected to one or more of circulation pumps 926 and / or disposed to accept the treated leachate to remove precipitates from the leaching solution during the electrolysis. A potentiostat 930 for supplying power to the anode 914 and cathode 918 is connected to the anode 914 and cathode 918. A pH probe 932 and pH meter 934 may be connected to the cathode chamber 920 and digital control system 946 to measure and adjust the system pH. The pH probe 932 and pH meter 934 may be employed to determine the appropriate time of electrolysis halt based on the pH of the leachate 913. A Fourier-transform infrared spectroscopy (FTIR) probe 942 is disposed in cathode chamber 920 and connected to FTIR meter 944 and digital control system 946.

[0092] The electrochemical membrane reactor 910 is integrated with the pH meter 934, a FTIR meter 944, and digital control system 946. FTIR probe 942 and FTIR meter 944 and pH probe 932 and pH meter 934 may monitor in situ the electrodialysis process of the leachate, in embodiments, of the leachate of carbonatite. The system 900 and reactor 910 may be used to sequentially precipitate elements, for example, ThCh. GatOHjs. Al(OH)?, hydroxides of rare earth metals, and Mg(0H)2; and electroplate metals, for example, Fe, Mo and Zn metal, and deposit Mn, V from the leachate of carbonatite. The FTIR probe 942 and pH probe 932 may function not only as sensors, detecting the different stages of separated products, but also to submit signals to the digital control system 946, which controls the electrolysis current or voltage applied on the electrochemical membrane reactor 910, the timing of exchanging the working electrode 918, and the switching on and off of the circulation pump 926 for precipitation / fdtrarion. The electrochemical membrane reactor 910 and automatic system (e.g., digital control system 946) effectively and thoroughly separate valuable elements (e.g.. Fe. Al. Th. Ga, and rare earth elements) consuming only electricity and water. The labor for the separation process is significantly reduced as compared to conventional systems and methods, and essentially no (zero) hazardous waste is generated. The electrochemical membrane reactor 910 and method thus enables sustainable mining (e.g., treatment and recycling of mining waste) with automatic control by using monitoring sensors.

[0093] An electrochemical membrane reactor for recycling, for example, spent permanent magnets is shown in FIG. 15. A system 1000 including an electrochemical membrane reactor 1010 includes an anode 1014 in an anode chamber 1016. The anode 1014 may be in the form of an anode container (e g., anode vessel) for holding the material (e.g., magnet powder) 1012 to be recycled. A cathode 1018 in a cathode chamber 1020 is separated from the anode chamber 101 by an ionic exchange membrane 1022. In embodiments of the disclosure, a copper metal is used as the cathode and a sodium sulfate solution is used as the electrolyte. An inlet 1024 (e.g., air / Ch / inert gas inlet) is connected to the cathode chamber 1020 for purging a gas (e.g., air / Ch / argon. nitrogen) into the cathode chamber 1020. Circulation pumps 1026a and 1026b are provided to circulate the leachate through the electrochemical membrane reactor 1010. Filter 1028 is connected to one or more of circulation pumps 1026a, 1026b to remove precipitates from the leaching solution during the electrolysis. A container 1038 may be connected to the filter 1028 to contain a treated leachate (e.g., residual solution, purified leachate). In operation, the anode 1014 oxidizes water (H2O) into protons (H+ions), which accelerate the leaching of the magnet powder 1012, and also oxidize the magnet powder 1012 to form Fe3+, Nd3+, Pr3+, and Dy3+ions, which dissolve into the electrolyte. The leachate containing the dissolved ions may be pumped into the cathode chamber 1020 by the circulation pump 1026a. O2 is purged into cathode chamber 1020 by inlet 1024 (e.g., inlet tube). O2 is reduced to OH' on the surface of the cathode 1018 and Al3+, Fe3+, and rare earth element ions in the electrolyte are hydrolyzed by the OH' ions sequentially. Based on the solubility of their hydroxides in aqueous solution, pH ranges, where substantially all of the ions from the magnets start to precipitate (at 10'2mol-L'1) and complete precipitation (at 10'5mol-L'1) may be determined. For example, Al3+and Fe3+ions may be removed from the leaching solution in a pH range of from about 2.0 to about 5.3, and the rare earth elements, including Nd3+, Pr3+, Dy?+ions, and the like, may be precipitated in a pH range of from about 5.3 to about 10.0. Even though Fe2+, Ni2+and Co2+ions precipitate in a pH range of from about 5.4 to about 10.3, which overlaps with the pH ranges for rare earth elements, the Ni2+and Co2+ions and Cu2+ions may be electroplated from the leachate solution, and Fe2+ions may be oxidized to Fe?+ions by the anode or by O2 purging into the cathode chamber. When the pH is greater than or equal to about 4.5, the thermodynamic potentials of Ni27Ni, Co2+ / Co and Cu27Cu couples are larger than the thermodynamic potential of H2 evolution reaction, illustrating the ability to electroplate Ni, Co and Cu from the aqueous electrolyte.

[0094] Thus, the electrochemical membrane reactor 1 10, 210, 310, 410, 510, 610, 710, 810, 910, 1010 and method extract desirable elements from geothermal brine, mines, mine slag, mine waste, Li metal / NMC batteries, or Li-ion batteries. Advantages of the reactor 110, 210. 310, 410, 510, 610, 710, 810, 910, 1010 and method herein provided include, but are not limited to. no or essentially no reagent depletion, and net zero emission for the separation and extraction acts. The reactors and methods reduce the overall cost as compared to methods having high chemical consumption. The reactors and methods enable extraction and / or separation of several elements in one efficient process. The reactors and methods enable superior selectivity by electrochemical precipitation as compared to chemical precipitation, which has the disadvantage of poor selectivity for element separation. Electrochemical precipitation has a higher elements selectivity than chemical precipitation methods. The reactors and methods according to embodiments of the disclosure are economically efficient, generating valuable by-product that may be reused. The reactors and methods remove impurities without introducing additional impurities, mitigating waste emission. The reactors and methods may be applied broadly to many different applications where extracting elements from materials is desired.

[0095] Table 1 shows removal of chemical elements conducted in multiple stages from a leachate prepared from spent lithium ion batteries (e.g.. black mass).

[0096] Table 1

[0097] Table 2 shows reactions occurring in different stages during element separation from a leachate prepared from carbonatite.

[0098] Table 2 Table 3 shows reactions occurring in different stages during element separation from a leachate prepared from spent magnets.

[0099] Table 3

[0100] Table 4 shows reactions occurring in different stages for element separation from a leachate prepared from bauxite residue.

[0101] Table 4 Table 5 shows reactions occurring in different stages for element separation from a leachate prepared from used nuclear fuel.

[0102] Table 5

[0103] The following examples sen e to explain embodiments of the disclosure in more detail. These examples are not to be construed as being exhaustive or exclusive as to the scope of this disclosure. Examples of electrification and decarbonization of impurity' removal from spent Li-ion batteries via a three-dimensional porous electrode.

[0104] Example 1 :

[0105] O2 reduction using Ni foam electrode.

[0106] A Ni foam (5 cm x 30 cm), porosity 110 ppi (pores per inch, the number of pores in one linear inch, MTI Korea) was coiled and inserted into a cylinder, which was used as a working electrode. The other cylinder, which was separated by an anion exchange membrane (FUMASEP® FAA-3-PK-130), had Ni plate (brand: IXGNIJ, 99.6 wt%) electrodes (4 cm x 4.5 cm) as anodes. The electrolyte was 0.2 rnol / 1'1K2SO4 solution. O2 gas was purged into the cylinder having the working electrode inside, and a Hg / Hg2SO4 reference electrode was positioned as close to the Ni foam as possible. The Ni foam electrode was subjected to a cyclic voltammetry' test between 0 V and 1 V at the scan rate of 5 mV s’1. Cyclic voltammetry (CV) of glassy carbon electrode in NiSO-i solution or CoSO4 solution.

[0107] 50 ml 0.12 mol / !'1NiSOr solution or 0.3 mol / L1CoSO4 solution was prepared as the electrolyte inside a four-neck flask, which was purged with N2 gas. Cyclic voltammetry was conducted with a glassy carbon (5 mm diameter) electrode as the working electrode, a graphite electrode (1 cm x 3 cm) as the counter electrode and a Hg / Hg2SO4 electrode as the reference electrode. The voltage scan interval was from 0.3 V and -1.2 V for NiSCL solution, and 0.7 V and -1.5 V for CoSO4 solution with the rate of 5 mV / s.

[0108] The bench-top electrochemical membrane reactor was tested for impurity removal from a simulated leaching solution.

[0109] The main body of the reactor was a three-cylinder “H” cell with two pieces of anion exchange membrane sandwiched between two of three adjacent cylinders. The Ni foam working electrode was in the middle and two Ni plates (or platinum foils) working as anodes were in the two sides of the cylinders. Two kinds of simulated leachates were prepared:

[0110] Sample 1: 7.533 g CuSO45H2O, 8.981 g A12(SO4)3 xH20, 1.5 g Fe2(SO4)3 xH20, 67.773 g MnSO4H2O, 23.332 g CoSO47H2O and 26.295 g NiSO46H2O were dissolved into 500 ml DI water.

[0111] Sample 2: 7.578 g CuSO45H2O, 10.253 g A12(SO4)3 xH2O. 1.531 g Fe2(SO4)3 xH20, 27.275 g MnSO4H2O, 24.207 g CoSO47H2O and 105.42 g N1SO4 6H2O were dissolved into 500 ml DI water.

[0112] As the leachate was acidic, the pH value of the solutions was adjusted to about 1.6 using concentrated H2SO4.

[0113] Sample 1 was used to simulate the leachate prepared from GM®, Ford®, and Fiat Chrysler Automobiles® (FCA) EV batteries reported in publications, but the impurity concentrations, including Cu2+, Fe3+and Al3+ions, were increased more than two or three times to test the capability of the reactor.

[0114] Sample 2 was used to simulate the leachate prepared from spent Li-ion batteries with Ni rich cathode and the impurity was intentionally increased as well.

[0115] For each experiment, 120 ml of solution was poured into the middle of the cylinder and 120 ml 0.2 K2SO4 was poured into the two side cylinders. The current from 20 mA to 40 mA passed through the reactor and the impurity was removed from the leachate gradually in the reaction mechanism shown in Table 6.

[0116] Table 6

[0117] Reactions for impurities removal from spent LIB In the electrochemical membrane reactor

[0118] In stage 1, no gas was purged into the reactor. The pH was increased to about 4.2 by H2O reduction and Cu2+ions were electroplated as well. In stage 2, O2 was purged into the leachate and was reduced to OH" ions, which precipitated Fe?+and Al3+ions. The anodic reaction inside the reactor depended on the material used for the anode. When the anode was Ni metal, Ni oxidation reaction was the dominant reaction. When Pt foil was used as the anode, H2O oxidation happened on this side.

[0119] Solution composition characterization by using ICP-MS and AAS.

[0120] The prepared solution before and after conducting the electrochemical processing, the solution from the precipitation digestion, and the electrode washing solution were measured to determine the concentration of each element by using iCAP Q ICP-MS and Agilent 240FS AA instruments.

[0121] Results and Discussion.

[0122] The electrochemical membrane reactor had the coiled Ni foam as its cathode, which supplied significantly larger electrode / electrolyte interface by comparison with a reactor having a two-dimensional plate as its cathode. The pores inside the Ni foam allowed ions to transmit from layer to layer and even the part in the central of the coil may be involved in reaction, as the shining plated Cu metal was later observed from the outside to the inside of the coiled Ni foam.

[0123] Before conducting impurity removal from the leachate, the electrode was employed for O2 reduction by using the three-electrode system first, as the experiment helped to understand how large of a current the electrode may supply for OH' ion generation, and the speed the reactor has for removing impurity from leachate. FIG. 4 is a graph showing current (mA. y-axis) versus potential (V, vs. Hg / Hg2SO4, x-axis). As shown in FIG. 4, the reduction current increased exponentially, as the potential decreased and was lower than -0.6 V (vs. Hg / Hg2SO4). When the potential reached to -0.97 V (vs. Hg / Hg2SO4), the current reached the limit of 200 mA that the potentiostat may supply. At small potential polarization, O2 was reduced to H2O2 first and then reduced to OH' ions. At large polarization, O2 was reduced to OH' ions directly. If the potential polarization was sufficiently large, Co2+and Ni2+ions were electroplated from the leachate as well. However, the reactor was designed to remove Cu2+, Fe?+, and Al?+ions from the leachate and keep Ni2+, Co2+and Mn2+ions in the leachate. Ni2+and Co2+ion electroplating was investigated by scanning glassy carbon electrode inside the NiSC and CoSO4 solution.

[0124] FIG. 5 is a graph showing current density (mA / cm2, y-axis) versus potential (V, vs. Hg / Hg2SO4, x-axis). FIG. 5 shows Ni2+ions start to deposit on the electrode when the potential was less than -1. 1 V (vs. Hg / Hg2SC>4) and the deposited Ni metal was oxidized when potential is larger than -0.55 V (vs. Hg / Hg2SO4). FIG. 6 is a graph showing cunent density (A / cm'2, y-axis) versus potential (V, vs. Hg / Hg2SO4, x-axis). FIG. 6 shows Co2+ions start to electroplate when the potential was lower than -1.2 V (vs. Hg / Hg2SO4). Based on the CV tests, the coiled Ni foam supplied 200 mA current from O2 reduction reaction at the potential of -0.97 V (vs. Hg / Hg2SO4) where Ni2+and Co2+ions’ electroplating potential was lower than that. If the electrode potential is uniformly distributed on the outside layer of the coiled Ni foam electrode, the electrode may at least supply 200 mA current for O2 reduction without plating Ni2+and Co2+ions. However, the coiled Ni foam was three dimensional, and the electrolyzer with conventional design, which had one plate counter electrode paralleling with the working electrode, could not overcome the drawback that a three-dimensional working electrode has: that is, the portion of the Ni foam, which is close to the counter electrode, may have a large potential polarization and the portion, which is far away, may have a small potential polarization. To eliminate non-uniform potential distribution as much as possible, two counter electrodes were introduced to both sides of the working electrode. By comparison with the two designs (one counter electrode and two side counter electrode), the reactor with two counter electrodes indeed had significantly better recovery efficiency of Ni, Co and Mn and a shortened processing time for impurity removal.

[0125] FIG. 7 is a line drawing of a bench-top reactor in accordance with embodiments of the disclosure. FIG. 8 is a line drawing of a coiled nickel foam electrode in accordance with embodiments of the present disclosure. FIG. 7 shows the bench-top reactor including the coiled nickel foam electrode (shown in FIG. 8) in the middle cylinder and two nickel plate counter electrodes in the two side cylinders. To selectively remove Fe3+, Al3+, and Cu2+ions and keep Co3+, Ni2+. and Fe3+ions inside the leachate of the spent lithium ion battery, the current for electrolysis was set to 40 mA in stage 1. and then was set to 20 mA in stage 2.

[0126] In stage 1, no gas was purged into the reactor and 40 mA current, which passed through the Ni foam electrode, was split into two pathways by the counter electrodes. Cu2+ions were electroplated, Fe3+ions were reduced to Fe2+ions, and H+ions and H2O were reduced to H2. When the pH of the simulated leachate was increased to about 4. the voltage applied on the reactor dropped from -2.4 V to about -3 V, indicating the reaction mechanism of H2 evolution changed. In the solution with low pH value, H+ions were reduced to H* atoms, which bond to the surface of the electrode and then combined to form H2. as shown in equations (12) and (13). In the solution with high pH value, the reaction undergoes H2O dissociation reaction first (equation (14) and (15)), which introduced a large energy barrier and overpotential for the reduction reaction. When the pH was increased to 4.2, precipitation appeared in the solution, and O2 was purged into the simulated leachate this time. Because the potential of O2 reduction was higher than the potential of H2 evolution at the same condition, the voltage applied to the reactor increased about 0.5 V automatically, after purging O2.

[0127] In the solution with high pH value, low H+ion concentration slowed down the kinetics of the O2 reduction reaction, and two electrons, instead of four electron transfer is O2 reaction mechanism at low potential polarization. However, only four electrons transfer for O2 reduction may sustain a constant current passing through the reactor while the pH increases gradually, and the reaction may need a large overpotential to dissociate H2O. For this reason, the voltage applied to the reactor dropped down gradually as the pH of the leachate increased. In case nickel and cobalt electroplate in the high pH value stage, the electrolysis current was changed to 20 mA at a pH of about 4.3 and was kept the same till the pH value of the solution reached to about 5.4. The Ni foam electrode was taken out from the reactor and was washed in deionized (DI) water twice with the help of ultrasonic treatment. The precipitates from both the simulated solution and the washing solution were filtered out using filter paper (fine pore). These solutions were diluted to between 20 and 400 times. The precipitates were digested with the mixture of concentrated HC1 and HNOs and then were diluted. Ion concentration in these solutions was tested with AAS and ICP-MS, and the results are shown below. Tables 7-12 show AAS and ICP-MS tests of the solutions before and after the electrochemical membrane reactor processing and the digested precipitates. (Ni plate anode, simulated solution: sample 1.) Tables 7-8 also show results for the electrochemical membrane reactor using a Pt foil as the anode. Table 7 shows AAS and ICP-MS analyses of the simulated solutions before and after the electrochemical membrane reactor electrodialysis, the deionized water from washing nickel foam, and the solution from digested precipitate using a nickel plate anode and simulated leachate 1. Table 8 shows the weight amount of each element in the simulated leachate 1.

[0128] Table 7 Table 8

[0129] Table 9 shows atomic absorption spectroscopy (AAS) and inductively coupled plasma mass spectrometry (ICP-MS analyses) of the simulated leachate 2 before and after the electrochemical membrane reactor electrodialysis, the deionized water from washing nickel foam and the solution from digested precipitates, using a nickel plate anode and simulated leachate 2. Table 10 shows the weight amount of each element in the simulated leachate 1.

[0130] Table 9 Table 10

[0131] Table 11 shows atomic absorption spectroscopy (AAS) and inductively coupled plasma mass spectrometry (ICP-MS analyses) of the simulated leachate 1 before and after the electrochemical membrane reactor electrodialysis, the deionized water from washing nickel foam and the solution from digested precipitates, using platinum foil anodes and simulated leachate 1. Table 12 shows the weight amount of each element in the simulated leachate 1.

[0132] Table 11 Table 12

[0133] Extraction reaction mechanisms, thermal dynamical electroplating potentials, and pH ranges to precipitate the elements are shown in Table 13 where 1g means Logio.

[0134] Table 13

[0135] Cl’ ions may coordinate with the metal ions, affecting their precipitation. For example, Cl’ ions may coordinate with Al3+and Fe3+ions to form [AICk]’ and [FeCh]’ complex ions. Due to the influence of Cl’ ions on Fe(OH)s solubility, the pH may be raised higher than the pH values shown in Table 13 for certain metal ions to precipitate effectively (e.g., in a desired time frame). Air may be purged into the brine 612 to oxidize Fe2+to Fe3+ions. A majority (e.g., 99%) of Fe2+ions may be oxidized in less than 50 minutes at pH = 7, while Mn2+ion oxidation is negligible at this pH value. One or more of O2 and air may also be reduced to produce OH’ ions, which increase pH. After the oxidation of Fe2+to Fe3+ions, air purging is not used, and the pH of the brine may be increased by reducing H2O to produce OH’. When the pH of the brine is adjusted to about 8.5 by the reactor, the concentrations of these elements, including Ag, Cu, Cd, Fe, Pb, Al, Zn, Al and Mg, may be reduced to less than 1 ppm through either the electroplating reaction or the electrochemical precipitation reaction, or both. When the pH is further elevated in the reactor to above pH 8.5, Mn2+ions start to precipitate. When the pH reaches about 10, greater than 99% of Mn2+ions may be extracted and less than 10 ppm of Mn2+ions remain in the brine. With pH continuously increasing above 10, Mg2+ions start to precipitate and less than 1 ppm of Mg2+ions may remain in the brine at pH 11.5. Therefore, the reactor not only extracts metal ions from brine, but also generates valuable byproducts, including Mn(0H)2, Mg(OH)2, NaCl, and H2SO4.

[0136] Additional non-limiting example embodiments of the disclosure are described below.

[0137] Embodiment 1 : An electrochemical membrane apparatus, comprising an electrochemical membrane reactor comprising one or more anodes contained in one or more anode chambers; one or more cathodes contained in one or more cathode chambers adjacent to the one or more anode chambers; at least one ionic exchange membrane disposed between at least one of the one or more anode chambers and the one or more cathode chambers; an inlet configured to supply a leaching solution to the one or more cathode chambers; a power source electrically coupled to the one or more anodes and the one or more cathodes and configured to apply a current between the one or more anodes and the one or more cathodes; a purging system configured to introduce one or more of air, O2, and an inert gas to the electrochemical membrane reactor; a pH measurement system coupled to the electrochemical membrane reactor; and an outlet configured to discharge a purified leaching solution.

[0138] Embodiment 2: The electrochemical membrane apparatus of embodiment 1, wherein the one or more anodes comprise a reactive metal or an inert metal.

[0139] Embodiment 3 : The electrochemical membrane apparatus of embodiment 1 or embodiment 2. wherein the one or more anodes surround the one or more cathodes.

[0140] Embodiment 4: The electrochemical membrane apparatus of any of embodiments 1-3, wherein at least a portion of the one or more anodes is laterally adjacent to at least a portion of the one or more cathodes. Embodiment 5 : The electrochemical membrane apparatus of any of embodiments 1-4, wherein the one or more cathodes comprise one or more cathode plates, one or more mesh cathodes, or one or more foam cathodes.

[0141] Embodiment 6: The electrochemical membrane apparatus of any of embodiments 1-5, wherein the one or more cathodes comprise one or more of a nickel mesh, a nickel foam, a nickel plate, a copper mesh, a copper foam, a copper plate, a stainless steel mesh, a stainless steel foam, a stainless steel plate, a titanium mesh, a titanium foam, a titanium plate, a carbon mesh, a carbon foam, and a carbon plate.

[0142] Embodiment 7 : The electrochemical membrane apparatus of any of embodiments 1-6, wherein the one or more cathodes exhibit a variable porosity across a thickness thereof or a variable pore size across a thickness thereof.

[0143] Embodiment 8: The electrochemical membrane apparatus of embodiment 7, wherein the variable porosity of the one or more cathodes comprises an outer portion of the cathode exhibiting a relatively larger porosity than the porosity of an inner portion of the cathode or wherein the variable pore size of the one or more cathodes comprises an outer portion of the cathode exhibiting a relatively larger pore size than the pore size of an inner portion of the cathode.

[0144] Embodiment 9: The electrochemical membrane apparatus of any of embodiments 1-8, wherein the at least one ionic exchange membrane disposed between at least one of the one or more anode chambers and the one or more cathode chambers comprises one or more of an anion exchange membrane, a cation exchange membrane, and a bipolar membrane.

[0145] Embodiment 10: The electrochemical membrane apparatus of any of embodiments 1-9, wherein a cathode chamber of the one or more cathode chambers is disposed between the two anode chambers.

[0146] Embodiment 1 1 : The electrochemical membrane apparatus of embodiment 10, wherein a first ionic exchange membrane of the at least one ionic exchange membrane is disposed between a first anode chamber of the two anode chambers and the cathode chamber: and a second ionic exchange membrane of the at least one ionic exchange membrane is disposed between the cathode chamber and a second anode chamber of the two anode chambers. Embodiment 12: The electrochemical membrane apparatus of any of embodiments 1-11, wherein the one or more cathodes comprises one or more of one or more porous cathodes and one or more cathode plates.

[0147] Embodiment 13: An electrochemical membrane apparatus, comprising an electrochemical membrane reactor comprising one or more anode chambers containing one or more anodes; a cathode chamber containing one or more cathodes; a first ionic exchange membrane disposed between a first anode chamber of the one or more anode chambers and a second ionic exchange membrane disposed adjacent the cathode chamber; a first intermediate chamber between the first ionic exchange membrane and the second ionic exchange membrane; a third ionic exchange membrane disposed between a second anode chamber of the one or more anode chambers and a fourth ionic exchange membrane disposed adjacent the cathode chamber; a second intermediate chamber between the third ionic exchange membrane and the fourth ionic exchange membrane; an inlet configured to supply a leaching solution to the one or more cathode chambers; a power source electrically coupled to the one or more anodes and the one or more cathodes and configured to apply a current between the one or more anodes and the one or more cathodes; a purging system configured to introduce one or more of air, O2, and an inert gas to the electrochemical membrane reactor; a pH measurement system coupled to the electrochemical membrane reactor; and an outlet configured to discharge a purified leaching solution.

[0148] Embodiment 14: A method of separating elements from a leaching solution using an electrochemical membrane apparatus, comprising introducing a leaching solution into an electrochemical membrane reactor, the leaching solution comprising one or more of one or more alkaline metals, one or more alkaline earth metals, one or more actinoids, one or more transition metals, one or more post-transition metals, one or more rare earth metals, one or more metalloids, one or more reactive non-metals, bauxite, and carbonatite, the electrochemical membrane reactor comprising one or more anodes contained in one or more anode chambers; one or more cathodes contained in one or more cathode chambers adjacent to the one or more anode chambers; at least one ionic exchange membrane disposed between at least one of the one or more anode chambers and the one or more cathode chambers; an inlet configured to supply a leaching solution to the one or more cathode chambers; a power source electrically coupled to the one or more anodes and the one or more cathodes and configured to apply a current between the one or more anodes and the one or more cathodes; a purging system configured to introduce one or more of air, O2. and an inert gas to the electrochemical membrane reactor; a pH measurement system coupled to the electrochemical membrane reactor; and an outlet configured to discharge a purified leaching solution; applying a current between the one or more anodes and the one or more cathodes of the electrochemical membrane reactor to adjust a pH of the leaching solution; introducing one or more of air. O2. and an inert gas to the electrochemical membrane reactor; depositing at least one metal from the leaching solution on the one or more cathodes of the electrochemical membrane reactor; precipitating one or more of the one or more transition metals, the one or more post-transition metals, the one or more actinoids, and the one or more rare earth metals from the leaching solution; and recovering one or more of the one or more transition metals, the one or more actinoids, the one or more post-transition metals, and the one or more rare earth metals, from the leaching solution.

[0149] Embodiment 15: The method of embodiment 14, wherein introducing a leaching solution into the electrochemical membrane reactor comprises introducing a leaching solution comprising one or more of copper, aluminum, iron, niobium, cobalt, manganese, nickel, gallium, potassium, tin, boron, silver, sodium, zinc, lead, zirconium, molybdenum, chromium, thorium, rubidium, caesium, calcium, magnesium, strontium, vanadium, titanium, scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, dysprosium, antimony, gadolinium, europium, plutonium, uranium, neptunium, americium, niobium, technetium, rhodium, silicon, sulfate, tellurium, selenium, sulfate, nitrate, and chloride into the electrochemical membrane reactor; depositing at least one metal on the cathode comprises depositing one or more of copper, nickel, zinc, lead, tin, cobalt, iron, silver, molybdenum, rubidium, and antimony on the cathode; precipitating one or more of the one or more transition metals, the one or more post-transition metals, the one or more actinoids, and the one or more rare earth metals from the leaching solution comprises removing one or more of zirconium, chromium, gallium, thorium, aluminum, uranium, plutonium, neptunium, , americium, tin, antimony, and iron from the leaching solution; and recovering one or more of the one or more transition metals, the one or more post-transition metals, the one or more actinoids, and the one or more rare earth metals, from the leaching solution comprises recovering one or more of cobalt, manganese, nickel, magnesium, one or more actinoids, and one or more rare earth metals from the leaching solution. Embodiment 16: The method of embodiment 14, wherein introducing a leaching solution into the electrochemical membrane reactor comprises introducing a leaching solution obtained from one or more of lithium ion batteries, ferromanganese slag, mining waste, mining tailings, mining residue, bauxite, bauxite residue, carbonatite, geothermal brine, used nuclear fuel, coal, and coal ash.

[0150] Embodiment 17: The method of any of embodiments 14-16, wherein introducing a leaching solution into an electrochemical membrane reactor comprises introducing a leaching solution into an electrochemical membrane reactor wherein the at least one ionic exchange membrane disposed between at least one of the one or more anode chambers and the one or more cathode chambers comprises one or more of an anion exchange membrane, a cation exchange membrane, and a bipolar membrane; wherein the one or more of an anion exchange membrane, a cation exchange membrane, and a bipolar membrane form one or more intermediate chambers between a cathode chamber and an anode chamber through which electrolyte may pass; the method further comprising passing electrolyte through one or more of the one or more intermediate chambers, wherein the electrolyte comprises one or more of Na2SO4, K2SO4, Na2COs, K2CO3, CaSCE, NaCl, KC1, CaCh, NaClC , KCIO4, Ca(C104)2, NasPCU, and K3PO4.

[0151] Embodiment 18: The method of any of embodiments 14-17, wherein introducing a leaching solution into an electrochemical membrane reactor comprises introducing a leaching solution into an electrochemical membrane reactor wherein the one or more anodes comprises one or more reactive metal anodes; the method further comprising introducing an electrolyte solution into the one or more cathode chambers; and reversing polarity of the electrochemical membrane reactor to electroplate dissolved reactive anode metal ions back onto the one or more reactive metal anodes.

[0152] Embodiment 19: The method of embodiment 14, wherein introducing a leaching solution comprises introducing a leaching solution obtained from lithium ion batteries; introducing one or more of air, O2, and an inert gas to the electrochemical membrane reactor comprises introducing one or more of air and O2 to the electrochemical membrane reactor; wherein depositing at least one metal from the leaching solution on the one or more cathodes of the electrochemical membrane reactor removing one or more of C'u2. Fe?+, Fe2+ions from leaching solution and electroplating one or more of Cu and Fe onto the one or more cathodes; precipitating one or more of the one or more transition metals, the one or more post-transition metals, and the one or more rare earth metals from the leaching solution comprises removing one or more of Fe3+, Fe2+, Al3+, Zr4, and Cr3+ions from the leaching solution while one or more of Co2+, Ni+, and Mn2+ions remain in the leaching solution; and applying a cunent between the one or more anodes and the one or more cathodes of the electrochemical membrane reactor to adjust a pH of the leaching solution comprises applying the current to adjust the pH of the leaching solution to a pH of greater than about 4 and less than about 6.5, and stopping the application of current at the pH of greater than about 4 and less than about 6.5. to reduce a concentration of one or more of Cu3+, Fe3+, Al3+, Zr4+, and Cr3+ions to about 5 ppm or less than about 5 ppm.

[0153] Embodiment 20: The method of embodiment 14, wherein introducing a leaching solution into the electrochemical membrane reactor comprises introducing a leaching solution obtained from one or more of used nuclear fuel, mining waste, mining tailings, and mining residue not the electrochemical membrane reactor; depositing at least one metal on the cathode comprises depositing one or more of Cu, Ni, Zn, Mo, Fe, Pb, Co, Mn, Sn and V; precipitating one or more of the one or more transition metals, the one or more posttransition metals, and the one or more actinoids from the leaching solution comprises removing one or more of Th, U, Mo, Ga, Cr, Zr, Al, Fe, Pu, and Sn before the pH reaches about 6; and recovering one or more of the one or more transition metals, the one or more post-transition metals, and the one or more rare earth metals, from the leaching solution comprises recovering one or more of magnesium and one or more rare earth elements from the leaching solution.

[0154] The embodiments of the disclosure described above and illustrated in the accompanying drawings do not limit the scope of the disclosure, which is encompassed by the scope of the appended claims and their legal equivalents. Any equivalent embodiments are within the scope of this disclosure. Indeed, various modifications of the disclosure, in addition to those shown and described herein, such as alternate useful combinations of the elements described, will become apparent to those skilled in the art from the description. Such modifications and embodiments also fall within the scope of the appended claims and equivalents.

Claims

CLAIMSWhat is claimed is:

1. An electrochemical membrane apparatus, comprising: an electrochemical membrane reactor comprising: one or more anodes contained in one or more anode chambers; one or more cathodes contained in one or more cathode chambers adjacent to the one or more anode chambers; at least one ionic exchange membrane disposed between at least one of the one or more anode chambers and the one or more cathode chambers; an inlet configured to supply a leaching solution to the one or more cathode chambers; a power source electrically coupled to the one or more anodes and the one or more cathodes and configured to apply a current between the one or more anodes and the one or more cathodes; a purging system configured to introduce one or more of air, O2, and an inert gas to the electrochemical membrane reactor; a pH measurement system coupled to the electrochemical membrane reactor; and an outlet configured to discharge a purified leaching solution.

2. The electrochemical membrane apparatus of claim 1, wherein the one or more anodes comprise a reactive metal or an inert metal.

3. The electrochemical membrane apparatus of claim 1, wherein the one or more anodes surround the one or more cathodes.

4. The electrochemical membrane apparatus of claim 3, wherein at least a portion of the one or more anodes is laterally adjacent to at least a portion of the one or more cathodes.

5. The electrochemical membrane apparatus of claim 1, wherein the one or more cathodes comprise one or more cathode plates, one or more mesh cathodes, or one or more foam cathodes.

6. The electrochemical membrane apparatus of claim 1, wherein the one or more cathodes comprise one or more of a nickel mesh, a nickel foam, a nickel plate, a copper mesh, a copper foam, a copper plate, a stainless steel mesh, a stainless steel foam, a stainless steel plate, a titanium mesh, a titanium foam, a titanium plate, a carbon mesh, a carbon foam, and a carbon plate.

7. The electrochemical membrane apparatus of any one of claims 1-6, wherein the one or more cathodes exhibit a variable porosity across a thickness thereof or a variable pore size across a thickness thereof.

8. The electrochemical membrane apparatus of claim 7, wherein the variable porosity of the one or more cathodes comprises an outer portion of the cathode exhibiting a relatively larger porosity than the porosity of an inner portion of the cathode or wherein the variable pore size of the one or more cathodes comprises an outer portion of the cathode exhibiting a relatively larger pore size than the pore size of an inner portion of the cathode.

9. The electrochemical membrane apparatus of any one of claims 1-6, wherein the at least one ionic exchange membrane disposed between at least one of the one or more anode chambers and the one or more cathode chambers comprises one or more of an anion exchange membrane, a cation exchange membrane, and a bipolar membrane.

10. The electrochemical membrane apparatus of any one of claims 1-6, wherein a cathode chamber of the one or more cathode chambers is disposed between two anode chambers.1 1 . The electrochemical membrane apparatus of claim 10, wherein: a first ionic exchange membrane of the at least one ionic exchange membrane is disposed between a first anode chamber of the two anode chambers and the cathode chamber; anda second ionic exchange membrane of the at least one ionic exchange membrane is disposed between the cathode chamber and a second anode chamber of the two anode chambers.

12. The electrochemical membrane apparatus of any one of claim 1-6, wherein the one or more cathodes comprises one or more of one or more porous cathodes and one or more cathode plates.

13. An electrochemical membrane apparatus, comprising: an electrochemical membrane reactor comprising: one or more anode chambers containing one or more anodes; a cathode chamber containing one or more cathodes; a first ionic exchange membrane disposed between a first anode chamber of the one or more anode chambers and a second ionic exchange membrane disposed adjacent the cathode chamber; a first intermediate chamber between the first ionic exchange membrane and the second ionic exchange membrane; a third ionic exchange membrane disposed between a second anode chamber of the one or more anode chambers and a fourth ionic exchange membrane disposed adjacent the cathode chamber; a second intermediate chamber between the third ionic exchange membrane and the fourth ionic exchange membrane; an inlet configured to supply a leaching solution to the one or more cathode chambers; a power source electrically coupled to the one or more anodes and the one or more cathodes and configured to apply a current between the one or more anodes and the one or more cathodes; a purging system configured to introduce one or more of air, O2, and an inert gas to the electrochemical membrane reactor; a pH measurement system coupled to the electrochemical membrane reactor; and an outlet configured to discharge a purified leaching solution.

14. A method of separating elements from a leaching solution using an electrochemical membrane apparatus, comprising: introducing a leaching solution into an electrochemical membrane reactor, the leaching solution comprising one or more of one or more alkaline metals, one or more alkaline earth metals, one or more actinoids, one or more transition metals, one or more post-transition metals, one or more rare earth metals, one or more metalloids, one or more reactive non-metals, bauxite, and carbonatite, the electrochemical membrane reactor comprising: one or more anodes contained in one or more anode chambers; one or more cathodes contained in one or more cathode chambers adjacent to the one or more anode chambers; at least one ionic exchange membrane disposed between at least one of the one or more anode chambers and the one or more cathode chambers; an inlet configured to supply a leaching solution to the one or more cathode chambers; a power source electrically coupled to the one or more anodes and the one or more cathodes and configured to apply a current between the one or more anodes and the one or more cathodes; a purging system configured to introduce one or more of air, O2, and an inert gas to the electrochemical membrane reactor; a pH measurement system coupled to the electrochemical membrane reactor; and an outlet configured to discharge a purified leaching solution; apply ing a current between the one or more anodes and the one or more cathodes of the electrochemical membrane reactor to adjust a pH of the leaching solution; introducing one or more of air, O2, and an inert gas to the electrochemical membrane reactor; depositing at least one metal from the leaching solution on the one or more cathodes of the electrochemical membrane reactor; precipitating one or more of the one or more transition metals, the one or more posttransition metals, the one or more actinoids, and the one or more rare earth metals from the leaching solution; andrecovering one or more of the one or more transition metals, the one or more actinoids, the one or more post-transition metals, and the one or more rare earth metals, from the leaching solution.

15. The method of claim 14, wherein: introducing a leaching solution into the electrochemical membrane reactor comprises introducing a leaching solution comprising one or more of copper, aluminum, iron, niobium, cobalt, manganese, nickel, gallium, potassium, tin, boron, silver, sodium, zinc, lead, zirconium, molybdenum, chromium, thorium, rubidium, caesium, calcium, magnesium, strontium, vanadium, titanium, scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, dysprosium, antimony, gadolinium, europium, plutonium, uranium, neptunium, americium, niobium, technetium, rhodium, silicon, sulfate, tellurium, selenium, sulfate, nitrate, and chloride into the electrochemical membrane reactor; depositing at least one metal on the cathode comprises depositing one or more of copper, nickel, zinc, lead, tin, cobalt, iron, silver, molybdenum, rubidium, and antimony on the cathode; precipitating one or more of the one or more transition metals, the one or more posttransition metals, the one or more actinoids, and the one or more rare earth metals from the leaching solution comprises removing one or more of zirconium, chromium, gallium, thorium, aluminum, uranium, plutonium, neptunium, americium, tin, antimony, and iron from the leaching solution; and recovering one or more of the one or more transition metals, the one or more post-transition metals, the one or more actinoids, and the one or more rare earth metals, from the leaching solution comprises recovering one or more of cobalt, manganese, nickel, magnesium, one or more actinoids, and one or more rare earth metals from the leaching solution.

16. The method of claim 14, wherein introducing a leaching solution into the electrochemical membrane reactor comprises introducing a leaching solution obtained from one or more of lithium ion batteries, ferromanganese slag, mining waste, mining tailings, mining residue, bauxite, bauxite residue, carbonatite, geothermal brine, used nuclear fuel, coal, and coal ash.

17. The method of any one of claims 14-16, wherein introducing a leaching solution into an electrochemical membrane reactor comprises introducing a leaching solution into an electrochemical membrane reactor wherein the at least one ionic exchange membrane disposed between at least one of the one or more anode chambers and the one or more cathode chambers comprises one or more of an anion exchange membrane, a cation exchange membrane, and a bipolar membrane; wherein the one or more of an anion exchange membrane, a cation exchange membrane, and a bipolar membrane form one or more intermediate chambers between a cathode chamber and an anode chamber through which electrolyte may pass; the method further comprising passing electrolyte through one or more of the one or more intermediate chambers, wherein the electrolyte comprises one or more of Na2SO4, K2SO4, Na2CO3, K2CO3, CaSO4, NaCl, KC1, CaCl2, NaC104, KC1O4, Ca(C104)2, Na3PO4, and K3PO4.

18. The method of any one of claims 14-16. wherein introducing a leaching solution into an electrochemical membrane reactor comprises introducing a leaching solution into an electrochemical membrane reactor wherein the one or more anodes comprises one or more reactive metal anodes; the method further comprising: introducing an electrolyte solution into the one or more cathode chambers; and reversing polarity of the electrochemical membrane reactor to electroplate dissolved reactive anode metal ions back onto the one or more reactive metal anodes.

19. The method of claim 14, wherein: introducing a leaching solution comprises introducing a leaching solution obtained from lithium ion batteries; introducing one or more of air, O2, and an inert gas to the electrochemical membrane reactor comprises introducing one or more of air and O2 to the electrochemical membrane reactor; wherein depositing at least one metal from the leaching solution on the one or more cathodes of the electrochemical membrane reactor removing one or more of Cu2+, Fe?+, Fe2ions from leaching solution and electroplating one or more of Cu and Fe onto the one or more cathodes;precipitating one or more of the one or more transition metals, the one or more posttransition metals, and the one or more rare earth metals from the leaching solution comprises removing one or more of Fe3+, Fe2+’ Al3+, Zr4+, and Cr3+ions from the leaching solution while one or more of Co2+, Ni+, and Mn2+ions remain in the leaching solution; and applying a current between the one or more anodes and the one or more cathodes of the electrochemical membrane reactor to adjust a pH of the leaching solution comprises applying the current to adjust the pH of the leaching solution to a pH of greater than about 4 and less than about 6.5, and stopping the application of current at the pH of greater than about 4 and less than about 6.5, to reduce a concentration of one or more of Cu3+, Fe3+, Al3+. Zr4+, and Cr3+ions to about 5 ppm or less than about 5 ppm.

20. The method of claim 14, wherein: introducing a leaching solution into the electrochemical membrane reactor comprises introducing a leaching solution obtained from one or more of used nuclear fuel, mining waste, mining tailings, and mining residue not the electrochemical membrane reactor; depositing at least one metal on the cathode comprises depositing one or more of Cu, Ni, Zn. Mo, Fe, Pb, Co, Mn. Sn. and V; precipitating one or more of the one or more transition metals, the one or more posttransition metals, and the one or more actinoids from the leaching solution comprises removing one or more of Th, U, Mo, Ga, Cr, Zr, Al, Fe, and Pu, Sn before the pH reaches about 6; and recovering one or more of the one or more transition metals, the one or more post-transition metals, and the one or more rare earth metals, from the leaching solution comprises recovering one or more of magnesium and one or more rare earth elements from the leaching solution.

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