Electrocoagulation and electrochemical oxidation process for removal of organic contaminants

Abstract

Methods of treating contaminated water having organic contaminants and metal species are disclosed. The methods include coagulating the organic contaminant and the metal species to produce solids, separating the solids, and electrochemically treating the water. Methods including directing the contaminated water to an electrocoagulation cell, a solids-liquid separator, and an electrooxidation cell are also disclosed. Systems for recovering metals from battery processing water are also disclosed. The systems include an electrocoagulation cell, a solids-liquid separator, and an electrooxidation cell.

Description

[0001] ELECTROCOAGULATION AND ELECTROCHEMICAL OXIDATION PROCESS FOR REMOVAL OF ORGANIC CONTAMINANTS

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Application Serial No. 63 / 531,826 titled “TOC Removal Using Membranes Process and Electrochemical Oxidation Processes” filed on August 10, 2023, which is herein incorporated by reference in its entirety for all purposes.

[0004] FIELD OF TECHNOLOGY

[0005] Aspects and embodiments disclosed herein relate to methods of treating water comprising at least one organic contaminant. In particular, aspects and embodiments disclosed herein relate to methods of treating water with electrocoagulation and electrochemical processes.

[0006] SUMMARY

[0007] In accordance with one aspect, there is provided a method of treating contaminated water. The method may comprise providing a contaminated water comprising a first concentration of at least one organic contaminant and a first concentration of a metal species. The method may comprise coagulating the at least one organic contaminant and the metal species to produce solids comprising the at least one organic contaminant and the metal species. The method may comprise separating at least some of the solids from the contaminated water to produce a first treated water and separated solids. The method may comprise electrochemically treating the first treated water with a cathode and an anode comprising an anodic oxidation material to produce a second treated water having a second concentration of the at least one organic contaminant lower than the first concentration of the at least one organic contaminant and a second concentration of the metal species lower than the first concentration of the metal species.

[0008] In some embodiments, coagulating comprises dosing the water with a coagulant to produce the solids.

[0009] In some embodiments, coagulating comprises electrochemically treating the water with a cathode and an anode comprising a sacrificial metal material to produce the solids. In some embodiments, the method further comprises recovering the metal species from the separated solids.

[0010] In some embodiments, the method further comprises separating residual solids from the second treated water to produce a third treated water and residual separated solids.

[0011] In some embodiments, the method further comprises recovering the metal species from the residual separated solids.

[0012] In some embodiments, the method further comprises controlling at least one of a reaction time for the coagulation and a reaction time for the electrochemical treatment.

[0013] In some embodiments, the method further comprises dosing the contaminated water with a flocculant prior to separating the at least some of the solids.

[0014] In some embodiments, the contaminated water comprises a first concentration of perfluoroalkyl and polyfluoroalkyl substances (PFAS), and the second treated water comprises a second concentration of PFAS lower than the first concentration of PFAS.

[0015] In some embodiments, the contaminated water comprises battery processing water.

[0016] In some embodiments, the metal species comprise lithium and cobalt.

[0017] In some embodiments, the second treated water comprises less than 100 ppm total organic carbon (TOC).

[0018] In accordance with another aspect, there is provided a method of treating contaminated water comprising a first concentration of at least one organic contaminant and a first concentration of a metal species. The method may comprise directing the contaminated water to an electrocoagulation cell having a first cathode and a first anode comprising a sacrificial metal to produce solids comprising the at least one organic contaminant and the metal species. The method may comprise directing the contaminated water and the solids to a first solids-liquid separator to produce a first treated water and separated solids. The method may comprise directing the first treated water to an electrooxidation cell having a second cathode and a second anode comprising an anodic oxidation material to produce a second treated water having a second concentration of the at least one organic contaminant lower than the first concentration of the at least one organic contaminant and a second concentration of the metal species lower than the first concentration of the metal species.

[0019] In some embodiments, the method further comprises directing the second treated water to a second solids-liquid separator. In some embodiments, the method further comprises directing the separated solids to a metal recovery unit.

[0020] In some embodiments, the method further comprises controlling at least one of residence time of the contaminated water in the electrocoagulation cell, residence time of the first treated water in the electrooxidation cell, potential applied to the electrocoagulation cell, or potential applied to the electrooxidation cell.

[0021] In accordance with another aspect, there is provided a system for recovering metals from battery processing water comprising at least one organic contaminant and a metal species. The system may comprise an electrocoagulation cell having an inlet fluidly connectable to a source of the battery processing water, the electrocoagulation cell comprising a first cathode and a first anode comprising a sacrificial metal. The system may comprise a first solids-liquid separator having an inlet fluidly connectable to the outlet of the electrocoagulation cell, a solids-ffaction outlet and a liquid-fraction outlet. The system may comprise an electrooxidation cell having an inlet fluidly connectable to the liquid-fraction outlet and an outlet, the electrooxidation cell comprising a second cathode and a second anode comprising an anodic oxidation material.

[0022] In some embodiments, the system further comprises a controller operable to generate a control signal that regulates at least one of residence time of the water in the electrocoagulation cell, residence time of the liquid-fraction in the electrooxidation cell, a potential applied to the electrocoagulation cell, or a potential applied to the electrooxidation cell.

[0023] In some embodiments, the system further comprises a sensor operably connected to the controller, the sensor configured to measure at least one of pH, flow rate, conductivity, current density, concentration of the at least one organic contaminant, and concentration of the at least one metal species.

[0024] In some embodiments, the system further comprises a second solids-liquid separator having an inlet fluidly connectable to the outlet of the electrooxidation cell.

[0025] In some embodiments, the system further comprises a metal recovery unit positioned downstream from the solids-fraction outlet.

[0026] In some embodiments, the sacrificial metal comprises aluminum and / or iron.

[0027] In some embodiments, the anodic oxidation material is selected from platinum, titanium oxide, a mixed metal oxide (MMO) coated dimensionally stable anode (DSA) material, graphite, graphene, boron doped diamond (BDD), lead / lead oxide, and combinations thereof. In some embodiments, the anodic oxidation material is titanium oxide of the formula TinChn-i, where n ranges from 3 to 9 inclusive.

[0028] In some embodiments, the source of the battery processing water comprises black mass leachate, battery shred water, and / or battery discharge water.

[0029] The disclosure contemplates all combinations of any one or more of the foregoing aspects and / or embodiments, as well as combinations with any one or more of the embodiments set forth in the detailed description and any examples.

[0030] BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures is represented by a like numeral. For purposes of clarity, not every component may be labeled in every drawing. In the drawings:

[0032] FIG. 1 is a box diagram of a system for treating contaminated water, according to one embodiment;

[0033] FIG. 2 is a box diagram of a system for treating contaminated water, according to another embodiment;

[0034] FIG. 3 is a box diagram of a system for treating contaminated water, according to another embodiment;

[0035] FIG. 4 is a box diagram of a system for treating contaminated water, according to another embodiment;

[0036] FIG. 5 is a box diagram of a system for treating contaminated water, according to another embodiment;

[0037] FIG. 6 is a schematic diagram of a system for treating contaminated water, according to one embodiment; and

[0038] FIG. 7 is a schematic diagram of a system for treating contaminated water, according to another embodiment.

[0039] DETAILED DESCRIPTION

[0040] The transition from a fossil fuel dependent economy to a renewable energy economy has introduced a large dependency on batteries. The use of rechargeable batteries has rapidly increased due to their known energy-efficient storage capabilities and the high demand on battery operated electronics and energy storage systems, such as electric vehicles (EVs).

[0041] Lithium-ion batteries (LIBs) are one exemplary type of rechargeable battery. LIBs have been widely utilized in various applications, such as consumer electronics, because of their superior energy density, long life type, and discharging capability. More recently, LIBs have been used in significant quantities for automotive propulsion as these batteries can provide many years of reliable service and are expected to last for about 10 years under normal driving conditions. LIBs may subsequently be used for utility energy storage but will eventually reach the end of their useful life.

[0042] LIBs often contain scarce and toxic elements such as lithium, cobalt, nickel, manganese, copper, aluminum, and graphite. For instance, LIBs generally include an anode, an electrolyte, and a cathode that contains lithium in the form of a lithium-transition metal oxide. The global availability of these elements is limited. LIBs present a supply chain risk as the demand for these elements is expected to exceed the supply. Thus, there is a need for efficient and cost-effective processes to manage and recycle the existing accumulation of spent LIBs and their constituent elements.

[0043] The processing of spent LIBs have created environmental concerns. There is a desire to recover usable materials from batteries and battery processing procedures. Recovery of materials may reduce the amount of materials extracted from the limited supplies in the environment. In addition, the negative environmental impacts caused by mining and processing ores (e.g., SOx emissions from smelting of sulfide ores, such as those that yield copper, nickel, and cobalt) may be reduced by recovery of materials from batteries.

[0044] There are currently two broad types of methods for recycling waste LIBs: the leaching method, and a combination method including calcination and leaching. Generally, the leaching method may include steps of crushing or chopping batteries and / or battery components, leaching with acid, separating the leached materials by precipitation, complexation, and / or extraction. However, the leaching method also involves the creation of complex leachate compositions and multiple separation steps that produce large amounts of secondary waste.

[0045] The combination method of calcination and leaching may generally include steps of crushing or chopping batteries and / or battery components, calcinating, leaching with acid, separating the leached materials by precipitation, complexation, and / or extraction. The combination method generally requires higher energy consumption caused by the heat-treating process. Additionally, the recovery rate of electrode materials may be lower, since some components of the electrode materials may be burned into carbon dioxide and other harmful substances.

[0046] Furthermore, current battery recycling methods involve advanced chemical and mechanical treatment systems that present limitations due to their waste complexity. Some of the greatest challenges with these current processes are optimization and wastewater treatment. Wastewater streams produced by the battery industry contain significant metal ion species, high levels of organic species, and other suspended solid waste. Additionally, such wastewater streams have been found to contain significant amounts of fluorinated compounds, such as perfluoroalkyl and polyfluoroalkyl substances (PFAS), which are notorious for being difficult contaminants to remove from wastewater streams. Common PFAS include perfluorooctanoic acid (PFOA) and / or perfluorooctane sulfonic acid (PFOS), but other fluorinated compounds may be found in battery processing wastewater streams.

[0047] Battery manufacturers and recycling processes are often required to implement on-site wastewater treatment systems, as regulatory discharge limits may not be met, and municipal wastewater infrastructure may be unable to support such high contamination levels. However, advantageously, the extraction of precious metal ions from battery recycling and manufacturing wastewater streams, commonly referred to as wastewater mining, can be accomplished with certain water treatment processes that offer successful separation.

[0048] Wastewater streams containing organic matter at high levels are generally treated by Fenton’s reaction principles. Fenton’s reaction processes typically utilize an oxidant, such as hydrogen peroxide, and ferrous ions to oxidize organic matter under acidic and high temperature conditions. High destruction rates have been achieved while treating organic matter with Fenton’s reactor processes. However, a significant solids loading is typically generated as a byproduct of the treatment.

[0049] Ultraviolet (UV) light may be used in a water treatment system to break down organic contaminants. For instance, ultraviolet radiation may convert certain organic contaminants in water into carbon dioxide and water. As another example, the ultraviolet radiation may convert halogenated compounds into halogenated acids. UV light may be used on its own, or in combination with another method of destroying organic contaminants. Electrochemical oxidation, also referred to herein as electrooxidation, is another exemplary process that may be employed to destroy organic contaminants in water. Electrochemical oxidation may be utilized to directly and / or indirectly oxidize electron-rich organic compounds by application of voltage, without production of major byproducts or harmful pollutants. Electrochemical oxidation may be implemented in an electrochemical cell having a cathode and an anode. The cathode and / or anode may be formed in a variety of shapes, for example, planar or circular. In at least some embodiments, the cathode and / or anode may be characterized by a foil, mesh, or foam structure, which may be associated with a higher active surface area, pore structure, and / or pore distribution that can provide ample active sites for the surface reactions to occur. For example, the cathode and / or anode may have an active area of from 1 cm2to 1000 cm2.

[0050] Electrochemical oxidation reactions generally occur on the surface of the anode. The anode material may be selected to be an anodic oxidation material that promotes oxidation of the organic contaminant. Exemplary anode materials include platinum, titanium oxide, a mixed metal oxide (MMO) coated dimensionally stable anode (DSA) material, graphite, graphene, boron doped diamond (BDD), or lead / lead oxide. DSA materials may be uncoated or may be coated with noble metals or metal oxides, such as IrCh, among others.

[0051] Titanium oxide anodes have been found to produce several advantages for the destruction of organic materials in wastewater streams, such as providing high corrosion resistance in acidic and basic conditions, high electrical conductivity, and high electro-chemical stability. Titanium oxide electrode materials may have a composition that follows the equation TinChn-i (n = 3-10), for example, TisOs, Ti4O?, TisOg, TieOn, and others. One exemplary titanium oxide electrode material is Ti4O?, sometimes referred to as a Magneli phase titanium oxide. Magneli phase titanium oxide electrodes and electrochemical cells comprising said electrodes are described in International Application Publication No. WO / 2020041712 (filed August 23, 2019, titled “System and method for electrochemical oxidation of polyfluoroalkyl substances in water”), the disclosure of which is herein incorporated by reference in its entirety for all purposes.

[0052] Another exemplary anode material is platinum, as its current-induced oxidation may be neglected at low current densities. Platinum may be used as a solid conductor or may be used as a coating on another electrode substrate, such as titanium. Platinum, graphite, or graphene may be uncoated or coated with an anodic oxidation material. The electrochemical cell may include a reference electrode, for example, in proximity to the cathode. A reference electrode may allow for continuous measurement of the potential of the working electrode, that is, the cathode, without passing current through it. The use of a reference electrode thus may allow for precise control over the cell voltage in water having a specific conductivity, therefore controlling the current that determines the reaction kinetics as described herein to limit competing reactions.

[0053] Electrochemical oxidation may also be used to remove fluorinated compounds, including perfluoroalkyl and polyfluoroalkyl substances (PF AS). These man-made chemical compounds are very stable and resilient to breakdown in the environment. These compounds may also be highly water soluble because they carry a negative charge when dissolved. The reaction may generally be characterized as a Kolbe-type oxidation.

[0054] The PFAS destruction reaction initiates from direct oxidation of carboxylate ions to carboxylate radicals (Eq. 1) on a titanium oxide (e.g., Ti4O?) surface by applying a sufficient positive voltage. The carboxylate radicals are subsequently decarboxylated to perfluoroalkyl radicals (Eq. 2). By coupling with hydroxyl free radicals which are anodically generated on the Ti4C>7 surface, the perfluoroalkyl radicals are converted to perfluoro alcohols (Eq. 3) which further defluorinate to perfluoro carbonyl fluoride (Eq. 4) and finally hydrolyze to a perfluorocarboxylic as a byproduct by losing one carbon in the chain (Eq. 5). Reactions 1 to 5 may generally be repeated until all carbon from PFASs are eventually stripped off to inorganic CO2, H+, and F.

[0055] Ti407+ C7F15COO - * Ti407+ C F4COO • + e (1)

[0056] C7F15COO • — » C7F15• +C02(2)

[0057] C7F15. +HO ^ C7F15OH (3)

[0058] C7F15OH -> C6F13C0F + H++ F~ (4)

[0059] C6F13COF + H20 C6F13COO~ + H++ F~ (5)

[0060] Removal of organic contaminants may also involve chemical treatment by coagulation. As used herein, “coagulation” refers to a chemical process in which non-settleable particles are destabilized and attract to form clumps. Coagulation is a chemical process achieved by modifying the electric charge of particles, for example, neutralizing particles to reduce the repelling force between them. Coagulation generally alters the chemistry of the suspension to induce agglomeration and settling.

[0061] Coagulation may be achieved by dosing the wastewater with a coagulant. Examples of coagulants generally include inorganic salts of aluminum and iron, for example, ferric chloride and ferric sulfates. These salts generally neutralize the charge on the particles and hydrolyze to form insoluble precipitates of the particles. Other examples of coagulants include organic coagulants, such as, diallyldimethylammonium chloride (D ADM AC).

[0062] Additionally or alternatively, coagulation may be achieved by application of an electric current, also referred to herein as electrochemical coagulation or electrocoagulation. The electric current may liberate ions from the surface of the electrode, that act to destabilize suspended and / or dissolved species in the wastewater suspension. The destabilized species may agglomerate to form insoluble precipitates. The electrochemical reactions taking place in the solution when a sacrificial metal M is used as the electrode are shown in equations (6)-(9) below, where reactions (6)-(7) take place at the anode and reactions (8)-(9) take place at the cathode.

[0063] 2H20 l) + 2e~ -> H2(tf) + 20H~ (9)

[0064] Exemplary electrodes for electrocoagulation may release aluminum and / or iron ions. If aluminum electrodes are used, Al3+(aq) ions may be generated at the anode. If iron electrodes are used, Fe2+ / Fe3+ions may be generated at the anode. The metal cations may undergo further spontaneous reactions to produce hydroxides, oxyhydroxides, and / or poly-hydroxides, which are capable of forming monomeric and polymeric ionic species, depending on the pH of the solution. The hydrolysis products have a high affinity for dispersed particles and charged particles to cause their coagulation. Furthermore, the gases produced at the electrodes may cause flotation of the precipitated flocs, which can be separated by filtration.

[0065] It is believed that electrocoagulation and electrochemical oxidation may have a synergistic effect on the removal of organic compounds from wastewater, and thus on the recovery of metal compounds. For instance, electrocoagulation may reduce the energy requirement for electrochemical oxidation. Electrocoagulation may further provide the benefit of reducing the amount of dosing agents required for the removal of organic contaminants from the wastewater by eliminating the need for addition of a chemical coagulant.

[0066] Flocculation may be used in combination with coagulation to generate larger particles for faster settling. As used herein, “flocculation” refers to a physical process in which particle clumps are physically joined to form larger particle masses and then a precipitate. Flocculation is a physical process of clumping. Flocculation can be achieved by physical agitation, for example, by mixing.

[0067] Optionally a flocculant can be added to aid in the flocculation process. Flocculants generally provide a base for the settling particles to physically attach and grow into a floc or flake. Exemplary flocculants include, for example, polymers, for example, high molecular weight polymers, medium molecular weight polymers, low molecular weight polymers, and cationic or anionic polymers.

[0068] Thus, coagulation may be used to clump the non-settleable particles together and a flocculant may be added to gather the small clumps formed by the coagulation and form larger clumps. However, a flocculation and coagulation need not be used together. Coagulation and flocculation may operate under different conditions. The conditions of the suspension to be treated, for example, pH, temperature, and composition, among others, may be considered when selecting whether to coagulate, flocculate, or both.

[0069] In accordance with one or more embodiments, systems and methods disclosed herein relate to the removal of organic compounds and fluorinated from a source of contaminated water. The systems and methods disclosed herein may also relate to the recovery of target compounds, such as heavy metal compounds, from the source of contaminated water. In certain embodiments, the source of the water may be associated with a battery processing system, such as battery manufacturing or recycling system or process.

[0070] Thus, battery processing water may include battery recycling water and / or battery recovery water. In certain embodiments, the battery processing water may include black mass leachate. As part of the recycling process, spent batteries may be broken down into smaller components by mechanical operations, such as shredding or crushing. Residual waste separated from the broken down batteries is referred to as black mass. The composition of the black mass can vary depending on the source battery (including factors such as the age and condition of the battery), recycling process, and efficiency of the production process. Black mass is then typically dissolved in a solution, often including a strong acid or base, to produce black mass leachate.

[0071] In certain embodiments, the battery processing water may include battery shred water. Shredding of the battery may be performed in an inert solution, for example, in a water bath or under a continuous or intermittent water shower. Contaminated water from the battery shredding process may be referred to as battery shred water.

[0072] In certain embodiments, the battery processing water may include battery discharge water. During the recycling and / or recovery process, spent batteries may be discharged by exposure to a salt solution. Exemplary salt solutions include aqueous NaCl, NazS, and MgSO4. After exposure to the spent battery, the contaminated solution may be referred to as battery discharge water.

[0073] In certain instances, the disclosure may refer to battery processing systems. However, it should be noted that the systems and methods disclosed herein may similarly be employed in association with any source of water including organic contaminants. For example, the source of the aqueous solution may be associated with a water purification, nuclear power generation, microelectronics manufacturing, semiconductor manufacturing, food processing (including agricultural uses and irrigation), textile manufacturing, paper manufacturing and recycling, pharmaceutical manufacturing, chemical processing, and metal extraction system or process. The source of the water may be associated with industrial applications, for example, with the removal of organic contaminants from industrial wastewaters. The source of the water may be associated with wastewater and / or municipal water treatment.

[0074] Furthermore, while the disclosure refers generally to lithium-ion battery processing and recycling, it should be understood that the systems and methods disclosed herein may similarly be employed for processing (including manufacturing and destroying) or recycling other battery types, such as alkaline batteries, lead batteries, or nickel cadmium batteries.

[0075] The effluent produced by the systems and methods disclosed herein may meet regulatory discharge requirements. In some embodiments, the effluent produced by the systems or methods disclosed herein may be collected and used for a variety of applications including battery manufacturing or recycling, industrial applications, electronics and semiconductor manufacturing, laboratory applications, medical grade uses, pharmaceutical manufacturing, beverage and food preparation, irrigation water, and agricultural applications. In one aspect, there is provided a method that enables separation and destruction of high levels of organic species and dissolved solids from a contaminated water source. The contaminated water may be subjected to a coagulation and filtration process to separate easily accessible organic species and total suspended solids (TSS). Total organic carbon (TOC) may be removed through electrochemical oxidation. The effluent may be treated by an optional polishing process, for example, membrane filtration.

[0076] While not wishing to be bound by theory, it is believed that coagulation improves solids and dissolved organic matter removal efficiency by increasing the molecular weight of suspended organic species and suspended solids, and thus, may decrease the operating costs of subsequent TOC removal processes. Coagulation may produce a smaller solid sludge compared to Fenton’s reaction, which may further decrease operating costs by reducing the overall volume of sludge processed. Filtration of coagulated solids may reduce the solids loading in subsequent steps. For instance, preceding a membrane treatment with coagulation may also reduce operating costs by reducing or eliminating TSS loading in the membrane stage and reducing or limiting the high levels of TOC.

[0077] Additionally, electrochemically treating the water to remove TOC may reduce or eliminate the need for external chemical reagents, such as chemical coagulants, and may reduce or eliminate heating requirements during chemical coagulation. Electrocoagulation and electrooxidation are believed to be more sustainable methods of reducing TSS and TOC in contaminated water.

[0078] The systems and methods disclosed herein may be utilized for recovery of metals from contaminated water. For instance, the systems and methods disclosed herein may be utilized for recovery of metals from battery processing water, such as battery recycling or battery recovery waters, e.g., black mass leachate, battery shred water, and / or battery discharge water. Furthermore, the systems and methods disclosed herein may be utilized to produce an effluent that meets regulatory discharge requirements. In certain embodiments, the systems and methods disclosed herein may be utilized to reclaim water from the battery processing operations.

[0079] Referring specifically to the figures, FIG. 1 is a box diagram of an exemplary system 1000 for treatment of contaminated water. The exemplary system 1000 of FIG. 1 includes a solids-liquid separator 200, a TOC removal unit 300 positioned downstream from an effluent outlet of the solids-liquid separator 200, and a second solids-liquid separator 400 positioned downstream from the effluent outlet of the TOC removal unit 300. Contaminated water is directed to the solids-liquid separator 200.

[0080] The upstream solids-liquid separator 200 may be utilized to separate suspended solids, such as total suspended solids (TSS), from the contaminated water. In certain exemplary embodiments, the solids-liquid separator 200 may be a bulk particulate filter, such as a filter having a pore size of 50-200 pm, for example, a 50-100 pm, 100-150 pm, or 150-200 pm pore size filter.

[0081] Downstream from the effluent outlet of the solids-liquid separator 200, the TOC removal unit 300 may remove finer and / or dissolved solids in the contaminated water. The TOC removal unit 300 be any processing unit capable of reducing TOC in the contaminated water stream. Exemplary TOC removal units 300 include an electrooxidation cell including a cathode and an anode, a Fenton’s reagent reactor including a source of an oxidant, and / or a UV radiation unit including a source of UV light. In certain embodiments, the TOC removal unit 300 may employ one or more TOC reducing processes.

[0082] The second solids-liquid separator 400 is an optional polishing unit positioned downstream from the effluent outlet of the TOC removal unit 300. Exemplary downstream solids-liquid separation units 400 include a nanofiltration unit (NF), a reverse osmosis unit (RO), or a microfiltration unit (MF).

[0083] FIG. 2 is a box diagram of an exemplary system 2000 for treatment of contaminated water. The system 2000 of FIG. 2 is similar to the system 1000 of FIG. 1, except that the system 2000 of FIG. 2 includes a coagulation unit 100 positioned upstream from the initial solids-liquid separator 200. Contaminated water is directed to the coagulation unit 100. The coagulation unit 100 may be configured to produce solids, such as solid agglomerates, of the organic contaminants and metal species in the contaminated water. The water including formed solids may then be directed to the solids-liquid separator 200 for separation of the formed solids.

[0084] In certain embodiments, the coagulation unit 100 may be a chemical coagulation unit, including a reactor and a source of a coagulant fluidly connected to the reactor. The source of the coagulant may dose the contaminant water with an effective amount of the coagulant to produce solids. In certain embodiments, the coagulation unit 100 may be an electrocoagulation cell, including a cathode and an anode. The electrocoagulation cell may be configured to produce solids from electrochemically generated ions. FIG. 3 is a box diagram of an exemplary system 3000 for treatment of contaminated water. The system 3000 of FIG. 3 is similar to the system 1000 of FIG. 1, except that the system 3000 of FIG. 3 includes a chemical pre-treatment unit 410 upstream from the polishing solids- liquid separator 400. The chemical pre-treatment unit 410 may include a source of a chemical pre-treatment agent fluidly connected upstream from the polishing solids-liquid separator 400. In some embodiments, the chemical pre-treatment unit 410 may comprise a source of an acid or a base for pH adjustment, a source of a coagulant and / or a flocculant, a source of chlorine, a source of an oxidant, a source of UV radiation, and / or an adsorbent.

[0085] FIG. 4 is a box diagram of an exemplary system 4000 for treatment of contaminated water. The system 4000 of FIG. 4 is similar to the system 1000 of FIG. 1, except that the system 4000 of FIG. 4 includes metal recovery units positioned downstream from a solids outlet of solids-liquid separator 200. The metal recovery units include a thickener 220 downstream from the solids outlet of the solids-liquid separator 200 and a filter press 230 downstream from the solids outlet of the thickener 220. Water recovered from the effluent of the thickener 220 and filter press 230 may be directed upstream for introduction into the contaminated water inlet stream. The filter cake produced from the filter press 230 may be processed for recovery of metals.

[0086] FIG. 5 is a box diagram of an exemplary system 5000 for treatment of contaminated water. The system 5000 of FIG. 5 is similar to the system 4000 of FIG. 4, except that the system 5000 of FIG. 5 includes a coagulation unit 100 positioned upstream from the solids-liquid separator 200. Water recovered from the effluent of the thickener 220 and filter press 230 may be directed upstream from the coagulation unit 100 for introduction into the contaminated water inlet stream.

[0087] FIG. 6 is a schematic diagram of an exemplary system 6000 for treatment of contaminated water. The exemplary system 6000 includes a source of contaminated water 700, which may be a battery processing water, a coagulation reactor 100 fluidly connected to the source of the contaminated water 700, including a source of a coagulant 110 and an optional source of a flocculant 120 fluidly connected thereto, a first solids-liquid separation unit 200 fluidly connected to the coagulation reactor 100, an electrooxidation cell 300 fluidly connected to the liquid-fraction outlet of the solids-liquid separator 200 including a cathode and an anode 310a, 310b, a second solids-liquid separation unit 400 fluidly connected to the electrooxidation cell 300, and a source of a chemical pre-treatment agent 410 fluidly connected to the solids- liquid separation unit 400.

[0088] A thickener 220 is positioned downstream from the solids-fraction outlet of the first solids-liquid separator 200. A filter press 230 is positioned downstream from the solids-fraction outlet of the thickener 220. Metal recovery may be performed on the solids-fraction. In certain embodiments, a metal recovery unit may be positioned downstream from the solids-fraction outlet of the solids-liquid separator 200, and optionally downstream from a solids-fraction outlet of the thickener 220 and / or the filter press 230. The liquid-fraction produced by the thickener 220 and filter press 230 may be directed upstream from the coagulation reactor 100.

[0089] The electrooxidation cell 300 may include a fluid recycle stream to maintain continuous or semi-continuous operation of the system. The electrooxidation cell 300 may also include a reference electrode 630 positioned to measure current density within the electrooxidation cell 300. The material and positioning (for example, distance) of the cathode 310a and anode 310b may be selected to control operation of the electrooxidation cell 300. The anode 310b may comprise or be formed of an anodic oxidation material. Exemplary anodic oxidation materials include platinum, titanium oxide, a mixed metal oxide (MMO) coated dimensionally stable anode (DSA) material, graphite, graphene, boron doped diamond (BDD), lead / lead oxide, and combinations thereof. In certain exemplary embodiments, the anode 310b may be a Magneli phase titanium oxide anode. For example, the anodic oxidation material may be titanium oxide of the formula TinChn-i, where n ranges from 3 to 9 inclusive.

[0090] The exemplary system 6000 includes controller 500, which is operably connected to the unit operations within the system 6000 and one or more pump or valve positioned to direct the flow of water through the system 6000. Controller 500 may be operable to generate a control signal that regulates at least one of residence time of the water in the coagulation reactor 100 or electrooxidation cell 300 or a potential applied to the electrooxidation cell 300. Controller 500 may be operably connected to one or more pump or valve to regulate residence time.

[0091] The exemplary system 6000 also includes sensor 600 positioned at the source of the contaminated water 700 to measure a property of the contaminated water. However, in certain embodiments, sensor 600 may be positioned in-line downstream from the source of the contaminated water 700. The exemplary system 6000 also includes sensor 620 positioned to measure a property of the effluent. Sensors 600, 620 may include one or more of a pH meter, a flow meter, a temperature sensor, a conductivity sensor, or a composition sensor, for example, configured to measure a concentration of one or more contaminant (e.g., organic contaminant, metal species, fluorinated compound, etc.). Sensors 600, 620 and reference electrode 630 are operably connected to controller 500, which may be programmed to generate a control signal that regulates at least one operating parameter of the system responsive to a measurement obtained by a sensor 600, 620 or a reference electrode 630 positioned within electrooxidation cell 300. Exemplary operating parameters of the system include flow rate (including residence time), pH, temperature, conductivity, current density, etc.

[0092] FIG. 7 is a schematic diagram of an exemplary system 7000 for treatment of contaminated water. The exemplary system 7000 is similar to the system 6000 of FIG. 6, except that the system 7000 includes an electrocoagulation cell 100a fluidly connected to the source of the contaminated water 700 including a cathode and an anode 110a, 110b, instead of a coagulation reactor 100. The source of the flocculant 120 may be fluidly connected to the electrocoagulation cell 110a or downstream from the electrocoagulation 110a (as shown in the exemplary embodiment of FIG. 7).

[0093] The electrocoagulation cell 100a may include a fluid recycle stream to maintain continuous or semi-continuous operation of the system. The electrocoagulation cell 100a may also include a reference electrode 610 positioned to measure current density within the electrocoagulation cell 610. The material and positioning (for example, distance) of the cathode 110a and anode 110b may be selected to control operation of the electrocoagulation cell 10a. The cathode 110a and / or anode 110b may comprise or be formed of a sacrificial metal material. Exemplary sacrificial metal materials include aluminum and / or iron.

[0094] Controller 500 may be operable to generate a control signal that regulates at least one of residence time of the water in the electrocoagulation cell 110a or electrooxidation cell 300, or a potential applied to the electrocoagulation cell 110a or electrooxidation cell 300. In certain embodiments, reference electrode 610 are operably connected to controller 500, which may be programmed to generate a control signal that regulates at least one operating parameter of the system responsive to a measurement obtained by a sensor 600, 620 or a reference electrode 610, 630 positioned within electrocoagulation cell 110a and / or electrooxidation cell 300.

[0095] In accordance with one aspect, there is provided a method of treating contaminated water. The method may comprise providing the contaminated water comprising a concentration of at least one organic contaminant and a concentration of a metal species. The contaminated water may further comprise a concentration of at least one fluorinated compound, such as perfluoroalkyl and poly fluoroalkyl substances (PFAS). In certain embodiments, the contaminated water may be a battery processing water, such as a battery recycling or a battery recovery water. Exemplary battery processing waters include black mass leachate, battery shred water, or battery discharge water. Thus, in certain embodiments, the metal species comprise lithium and cobalt. The metal species may comprise lithium, cobalt, nickel, manganese, copper, aluminum, graphite, or combinations thereof.

[0096] In certain embodiments, the contaminated water may have a total organic carbon (TOC) concentration of at least about 2000 ppm, for example, the contaminated water may have a TOC concentration of between about 2000 ppm to 5000 ppm, for example, 2000 to 2500 ppm, 2500 to 3000 ppm, 3000 to 3500 ppm, 3500 to 4000 ppm, 4000 ppm to 4500 ppm, or 4500 to 5000 ppm. The contaminated water may have a total suspended solids (TSS) concentration of at least about 100 ppm, for example, between about 100 ppm to 2000 ppm, for example, 100 to 250 ppm, 250 to 500 ppm, 500 to 750 ppm, 750 to 1000 ppm, 1000 to 1250 ppm, 1250 to 1500 ppm, or 1500 to 2000 ppm. The contaminated water may have a concentration of at least about 100 ppm Li, for example 100 to 1000 ppm Li; at least about 0.1 ppm Mg or Mn, for example 0.1 to 20 ppm or 1 to 10 ppm Mg or Mn; at least about 10 ppm Ni, for example, 10 to 300 ppm Ni; and / or at least about 50 ppm Al, for example, 50 to 1200 ppm Al. In general, the lower ends of the ranges may be associated with battery discharge water, while the higher ends of the ranges may be associated with battery shred water or black mass leachate.

[0097] The systems and methods disclosed herein may be used to produce a treated water (also referred to as an effluent herein) having lower concentrations of one or more of the organic contaminant, the metal species, and optionally the fluorinated compounds, such as PFAS. In certain embodiments, the treated water may meet regulatory discharge requirements. For instance, the treated water may have less than 100 ppm TOC. In certain embodiments, the treated water may have less than 75 ppm, less than 50 ppm, less than 25 ppm, or less than 10 ppm TOC. Thus, in certain embodiments, the systems and methods disclosed herein may reduce TOC of the contaminated water by at least at least 90%, at least 95%, at least 98%, at least 99%, at least 99.9%, at least 99.99%, or at least 99.999%. In some embodiments, the methods disclosed herein may be used to recover at least 90% of the metal species (one or more of lithium, cobalt, nickel, manganese, copper, aluminum, graphite, or combinations thereof) from the contaminated water, for example, at least 90%, at least 95%, at least 98%, at least 99%, at least 99.9%, at least 99.99%, or at least 99.999% of the metal species from the contaminated water.

[0098] The methods may comprise reducing suspended solids from the contaminated water. Suspended solids may be reduced by coagulating the at least one organic contaminant and the metal species to produce agglomerated solids. In certain embodiments, coagulation may be performed by dosing the contaminated water with an effective amount of at least one coagulant. In other embodiments, coagulation may be performed by electrochemically treating the water with a cathode and an anode comprising a sacrificial metal material to produce the solids. Thus, in certain embodiments, the methods may comprise directing the contaminated water to an electrocoagulation cell. The methods may comprise operating the electrocoagulation cell, for example, controlling a potential applied to the anode and the cathode, to generate ions that produce solids comprising the organic contaminant and metal species.

[0099] In some embodiments, the methods may further comprise flocculating the agglomerated solids to produce larger flocs. Flocculation may be performed by dosing the contaminated water with an effective amount of a flocculant. In certain embodiments, the contaminated water may be dosed with a flocculant prior to or subsequently with coagulation. In other embodiments, the contaminated water may be dosed with a flocculant after coagulation. Flocculation may be performed in combination with a chemical coagulant or electrocoagulation.

[0100] The method may comprise separating at least some of the solids from the contaminated water to reduce total suspended solids (TSS) concentration of the contaminated water and produce a treated water and separated solids. Thus, in some embodiments, the methods may comprise directing the contaminated water and solids to a solids-liquid separation unit. The solids-liquid separation unit may be configured to produce a liquid-fraction comprising the treated water having reduced TSS and a solids-fraction comprising the agglomerated solids. The liquid-fraction may then be treated to reduce TOC, while the solids-fraction may be treated for recovery of the metal species.

[0101] Thus, in some embodiments, the method may further comprise recovering the metal species from the separated solids. For instance, the methods may comprise thickening the separated solids. The methods may comprise directing the separated solids to a thickener. In some embodiments, the methods may further comprise directing the separated solids to a filter press. The thickener and / or filter press may be configured to further dewater the separated solids and produce a filter cake containing the metal species. In some embodiments, the methods may further comprise directing the separated solids to a metal recovery unit to recover at least some of the metal species for reuse. For instance, the methods may further comprise directing the dewatered solids (e.g., filter cake) to a metal recovery unit.

[0102] The methods may comprise reducing TOC of the contaminated water. In certain embodiments, the methods may comprise reducing TOC of the contaminated water by Fenton’s reaction, for example, by dosing the contaminated water with an oxidant. Exemplary oxidants include hydrogen peroxide, ozone, oxygen gas, and persulfate. The methods may comprise reducing TOC by exposure to UV light.

[0103] In some embodiments, the methods may comprise reducing TOC by electrochemically treating the treated water with a cathode and an anode comprising an anodic oxidation material. In certain embodiments, two or more of the TOC reducing processes may be used. Thus, in certain embodiments, the methods may comprise directing the water to an electrooxidation cell having a cathode and an anode comprising an anodic oxidation material. Exemplary anodic oxidation materials include platinum, titanium oxide, a mixed metal oxide (MMO) coated dimensionally stable anode (DS A) material, graphite, graphene, boron doped diamond (BDD), lead / lead oxide, and combinations thereof. In certain exemplary embodiments, the anode may be a Magneli phase titanium oxide anode. For example, the anodic oxidation material may be titanium oxide of the formula TinChn-i, where n ranges from 3 to 9 inclusive.

[0104] The treated water produced after TSS and TOC reduction may meet regulatory discharge requirements. For example, the treated water produced from the electrochemical oxidation may meet regulatory discharge requirements. For instance, the treated water may have less than 100 ppm TOC, or less than 75 ppm, less than 50 ppm, less than 25 ppm, or less than 10 ppm TOC, as previously described.

[0105] In certain embodiments, the methods may comprise further polishing the treated water. For instance, the methods may comprise separating residual solids from the treated water and producing a polished effluent. In some embodiments, the methods may comprise directing the treated water to a solids-liquid separator. Exemplary polishing solids-liquid separators include RO, NF, and / or MF separation processes. In some embodiments, metals may also be recovered from the residual solids. The methods may comprise dosing or treating the treated water with a chemical pre-treatment agent, optionally prior to separating the residual solids. Exemplary chemical pre-treatment agents include an acid or a base for pH adjustment, a coagulant and / or a flocculant, chlorine, an oxidant, UV radiation, and / or an adsorbent.

[0106] The methods may comprise controlling one or more parameter of the treatment process. For instance, the methods may comprise controlling a reaction time for the coagulation and / or a reaction time for the electrochemical oxidation. The methods may comprise controlling at least one of residence time of the contaminated water in the coagulation reactor or electrocoagulation cell, residence time of the first treated water in the electrooxidation cell, potential applied to the electrocoagulation cell, or potential applied to the electrooxidation cell. The parameter may be controlled to reduce a reaction time, improve removal or reduction of TSS and / or TOC from the contaminated water, and / or reduce energy usage by one or more unit operation.

[0107] The methods may comprise controlling one or more parameter of the water, for example, pH, flow rate, temperature, etc. In certain embodiments, the methods may comprise controlling a dosing rate of an agent, such as a coagulant, a flocculant, or a chemical pre-treatment agent. The methods may comprise controlling a dosing rate of an oxidant and / or intensity of UV light applied to the water.

[0108] In some embodiments, the methods may comprise measuring one or more parameter of the treatment process. For instance, the methods may comprise measuring one or more of pH, flow rate, temperature, conductivity, current density, or composition, for example, concentration of one or more contaminant, such as an organic contaminant, metal species, or fluorinated compound. The one or more parameter may be measured within the contaminated water, for example, prior to any treatment. The one or more parameter may be measured in the effluent or treated water. The one or more parameter may be measured within a unit operation, for example, within a coagulation reactor, electrocoagulation cell, or electrooxidation cell.

[0109] In certain embodiments, the parameter of the treatment process may be controlled responsive to one or more measurement. For instance, one or more of the residence time of the contaminated water in the coagulation reactor or electrocoagulation cell, residence time of the first treated water in the electrooxidation cell, potential applied to the electrocoagulation cell, or potential applied to the electrooxidation cell may be controlled responsive to a measurement, such as pH, flow rate, temperature, conductivity, current density, or composition. In some embodiments, one or more of pH, flow rate, temperature, dosing rate of an agent, such as a coagulant, flocculant, chemical pre-treatment agent, and / or oxidant, and / or intensity of UV light applied may be controlled responsive to a measurement.

[0110] The function and advantages of these and other embodiments can be better understood from the following examples. These examples are intended to be illustrative in nature and are not considered to be limiting the scope of the invention.

[0111] Contaminated water samples will be tested for reduction of organic species (TOC, TSS). The contaminated water samples may include battery processing water or manufactured water samples. The contaminated water samples will contain at least 3500 ppm TOC, at least 100 ppm TSS, and at least 100 ppm Li.

[0112] The contaminated water samples will be treated in a variety of comparative pilot systems including (1) a coagulation system, (2) a coagulation and electrochemical oxidation system, (3) a coagulation and oxidant dosing (Fenton’s reaction) system, and (4) a coagulation, electrochemical oxidation, and oxidant dosing system. The coagulation processes may include a chemical coagulant or an electrochemical coagulation process. A filter will be positioned between coagulation and downstream processes (electrochemical oxidation and / or oxidant). The electrochemical coagulation and electrochemical oxidation cells will be controlled to operate at 8.0. Volts. Amps, Conductivity, pH, ORP and TOC concentration will be monitored throughout testing.

[0113] The results are expected to be as follows: the sample treated by (1) coagulation is expected to have about 2500 ppm TOC, about 5 ppm TSS, and about 80 ppm Li; the sample treated by (2) coagulation and electrochemical oxidation is expected to have about 1000 ppm TOC, about 0 ppm TSS, and about 2 ppm Li; the sample treated by (3) coagulation and oxidant dosing is expected to have about 2250 ppm TOC, about 0 ppm TSS, and about 80 ppm Li; and (4) the sample treated by coagulation, electrochemical oxidation, and oxidant dosing is expected to have about 1500 ppm TOC, about 0 ppm TSS, and about 1 ppm Li.

[0114] Thus, the comparative tests are expected to show that combining coagulation and electrochemical oxidation will provide superior removal of organic contaminants from sample battery processing water as compared to coagulation alone and coagulation with oxidant dosing. It is further expected that controlling pH of the water stream prior to electrochemical oxidation will improve removal of organic contaminants from the sample. Additionally, increasing residence time through the electrochemical oxidation cell may also improve removal of organic contaminants from the sample. Residence time may be controlled, for example, increased, to produce a product water having less than 100 ppm TOC, or even less than 10 ppm TOC.

[0115] The phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. As used herein, the term “plurality” refers to two or more items or components. The terms “comprising,” “including,” “carrying,” “having,” “containing,” and “involving,” whether in the written description or the claims and the like, are open-ended terms, i.e., to mean “including but not limited to.” Thus, the use of such terms is meant to encompass the items listed thereafter, and equivalents thereof, as well as additional items. Only the transitional phrases “consisting of’ and “consisting essentially of,” are closed or semi-closed transitional phrases, respectively, with respect to the claims. Use of ordinal terms such as “first,” “second,” “third,” and the like in the claims to modify a claim element does not by itself connote any priority, precedence, or order of one claim element over another or the temporal order in which acts of a method are performed, but are used merely as labels to distinguish one claim element having a certain name from another element having a same name (but for use of the ordinal term) to distinguish the claim elements.

[0116] Having thus described several aspects of at least one embodiment, it is to be appreciated various alterations, modifications, and improvements will readily occur to those skilled in the art. Any feature described in any embodiment may be included in or substituted for any feature of any other embodiment. Such alterations, modifications, and improvements are intended to be part of this disclosure and are intended to be within the scope of the invention. Accordingly, the foregoing description and drawings are by way of example only.

[0117] Those skilled in the art should appreciate that the parameters and configurations described herein are exemplary and that actual parameters and / or configurations will depend on the specific application in which the disclosed methods and materials are used. Those skilled in the art should also recognize or be able to ascertain, using no more than routine experimentation, equivalents to the specific embodiments disclosed.

Claims

CLAIMS1. A method of treating contaminated water, comprising: providing a contaminated water comprising a first concentration of at least one organic contaminant and a first concentration of a metal species; coagulating the at least one organic contaminant and the metal species to produce solids comprising the at least one organic contaminant and the metal species; separating at least some of the solids from the contaminated water to produce a first treated water and separated solids; and electrochemically treating the first treated water with a cathode and an anode comprising an anodic oxidation material to produce a second treated water having a second concentration of the at least one organic contaminant lower than the first concentration of the at least one organic contaminant and a second concentration of the metal species lower than the first concentration of the metal species.

2. The method of claim 1, wherein coagulating comprises dosing the water with a coagulant to produce the solids.

3. The method of claim 1, wherein coagulating comprises electrochemically treating the water with a cathode and an anode comprising a sacrificial metal material to produce the solids.

4. The method of claim 1, further comprising recovering the metal species from the separated solids.

5. The method of claim 1, further comprising separating residual solids from the second treated water to produce a third treated water and residual separated solids.

6. The method of claim 5, further comprising recovering the metal species from the residual separated solids.

7. The method of claim 1, further comprising controlling at least one of a reaction time for the coagulation and a reaction time for the electrochemical treatment.

8. The method of claim 1, further comprising dosing the contaminated water with a flocculant prior to separating the at least some of the solids.

9. The method of claim 1, wherein the contaminated water comprises a first concentration of perfluoroalkyl and polyfluoroalkyl substances (PFAS), and the second treated water comprises a second concentration of PFAS lower than the first concentration of PFAS.

10. The method of claim 1, wherein the contaminated water comprises battery processing water.

11. The method of claim 10, wherein the metal species comprise lithium and cobalt.

12. The method of claim 1, wherein the second treated water comprises less than 100 ppm total organic carbon (TOC).

13. A method of treating contaminated water comprising a first concentration of at least one organic contaminant and a first concentration of a metal species, the method comprising: directing the contaminated water to an electrocoagulation cell having a first cathode and a first anode comprising a sacrificial metal to produce solids comprising the at least one organic contaminant and the metal species; directing the contaminated water and the solids to a first solids-liquid separator to produce a first treated water and separated solids; and directing the first treated water to an electrooxidation cell having a second cathode and a second anode comprising an anodic oxidation material to produce a second treated water having a second concentration of the at least one organic contaminant lower than the first concentration of the at least one organic contaminant and a second concentration of the metal species lower than the first concentration of the metal species.

14. The method of claim 13, further comprising directing the second treated water to a second solids-liquid separator.

15. The method of claim 13, further comprising directing the separated solids to a metal recovery unit.

16. The method of claim 13, further comprising controlling at least one of residence time of the contaminated water in the electrocoagulation cell, residence time of the first treated water in the electrooxidation cell, potential applied to the electrocoagulation cell, or potential applied to the electrooxidation cell.

17. A system for recovering metals from battery processing water comprising at least one organic contaminant and a metal species, comprising: an electrocoagulation cell having an inlet fluidly connectable to a source of the battery processing water, the electrocoagulation cell comprising a first cathode and a first anode comprising a sacrificial metal; a first solids-liquid separator having an inlet fluidly connectable to the outlet of the electrocoagulation cell, a solids-fraction outlet and a liquid- fraction outlet; and an electrooxidation cell having an inlet fluidly connectable to the liquid-fraction outlet and an outlet, the electrooxidation cell comprising a second cathode and a second anode comprising an anodic oxidation material.

18. The system of claim 17, further comprising a controller operable to generate a control signal that regulates at least one of residence time of the water in the electrocoagulation cell, residence time of the liquid-fraction in the electrooxidation cell, a potential applied to the electrocoagulation cell, or a potential applied to the electrooxidation cell.

19. The system of claim 18, further comprising a sensor operably connected to the controller, the sensor configured to measure at least one of pH, flow rate, conductivity, current density, concentration of the at least one organic contaminant, and concentration of the at least one metal species.

20. The system of claim 17, further comprising a second solids-liquid separator having an inlet fluidly connectable to the outlet of the electrooxidation cell.

21. The system of claim 17, further comprising a metal recovery unit positioned downstream from the solids-fraction outlet.

22. The system of claim 17, wherein the sacrificial metal comprises aluminum and / or iron.

23. The system of claim 17, wherein the anodic oxidation material is selected from platinum, titanium oxide, a mixed metal oxide (MMO) coated dimensionally stable anode (DSA) material, graphite, graphene, boron doped diamond (BDD), lead / lead oxide, and combinations thereof.

24. The system of claim 23, wherein the anodic oxidation material is titanium oxide of the formula TinOin-i, where n ranges from 3 to 9 inclusive.

25. The system of claim 17, wherein the source of the battery processing water comprises black mass leachate, battery shred water, and / or battery discharge water.

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