Recycling of metals from haptic feedback module of a portable electronic device

Abstract

Methods and systems for the extraction of magnetic material from magnet containing material and tungsten-containing material from end-of-life devices and for extraction of rare earth elements (REEs) from the magnetic material and tungsten from the tungsten-containing material in haptic feedback modules are disclosed.

Description

[0001] RECYCLING OF METALS FROM HAPTIC FEEDBACK MODULE OF A PORTABLE ELECTRONIC DEVICE

[0002] FIELD

[0003] The disclosure relates generally to recycle of valuable metals from electronic devices and particularly to recycle of rare earth elements and tungsten in haptic feedback modules.

[0004] BACKGROUND OF THE DISCLOSURE

[0005] Haptic technology is the technology that can create an experience of touch by applying forces, vibrations, or motions to the user of an electronic device, such as but not limited to a phone, smart watch, or tablet. A specific example of a haptic technology is the Taptic Engine™ to provide users with tactile feedback to simulate actions, such as clicks on a stationary touch screen. Tungsten is used in producing vibration motors, also known as haptic technology or more specifically mobile vibrators. These motors are integral components that provide tactile feedback to users, alerting them to incoming calls, messages, and notifications. Tungsten’s high density, hardness, high temperature resistance and wear resistance property helps to endure the high-speed rotational vibrations these motors generate.

[0006] Tungsten is the substitution of stainless steel and has a greater density (19.3 g / cm3) than stainless steel (7.7 g / cm3). As a result, tungsten provides a greater amount of mass per volume than stainless steel. Beneficially, a frame that is comprised of tungsten provides a stronger lower resonant frequency than the use of stainless steel in the frame. Tungsten is a denser material than stainless steel, and as a result, the tungsten may require more energy by the haptic feedback module to get up to speed compared to stainless steel. However, once the frame is up to speed, the tungsten may generate a greater amount of feel by the user than an equivalent frame that is comprised of stainless steel. In some examples, the use of tungsten in the frame results in a 15-25% gain in user feel relative to the use of stainless steel.

[0007] SUMMARY OF THE DISCLOSURE

[0008] These and other needs are addressed by the various embodiments and configurations of the present invention. The various embodiments and configurations can recover tungsten, rare earths, and other metals from a mixed feed material containing tungsten-containing material and (rare earth-containing) magnets, such as from haptic or taptic engines and other components of electronic devices.

[0009] In aspects of this disclosure, a method can include the steps of:

[0010] receiving the mixed feed comprising tungsten-containing material and magnets having different chemical compositions, wherein at least a portion of the magnets comprise rare earth elements;

[0011] comminuting the mixed feed to form a comminuted feed stream;

[0012] separating the comminuted tungsten-containing material from the comminuted magnets;

[0013] recovering the rare earth elements from the comminuted magnets; and recovering the tungsten from the tungsten-containing material.

[0014] In aspects of this disclosure, a method can include the steps of:

[0015] receiving a mixed feed comprising tungsten-containing material and magnets having different chemical compositions, wherein at least a portion of the magnets comprise rare earth elements, wherein the rare earth elements comprise one or more of neodymium, samarium, praseodymium, terbium, and dysprosium;

[0016] comminuting the mixed feed to form a comminuted feed stream;

[0017] acid leaching the comminuted magnets to form a pregnant leach solution comprising at least most of the one or more of neodymium, samarium, praseodymium, terbium, and dysprosium in the rare earth magnets and a residue comprising at least most of the tungsten in the tungsten-containing material;

[0018] oxidizing at least most of the tungsten in the tungsten-containing material; leaching the tungsten-containing material to form a pregnant leach solution comprising at least most of the oxidized tungsten in the tungsten-containing material; and recovering at least most of the tungsten from the pregnant leach solution.

[0019] In aspects of this disclosure, a method can include the steps of:

[0020] receiving a mixed feed comprising tungsten-containing material, plastics, and magnets having different chemical compositions, wherein at least a portion of the magnets comprise rare earth elements;

[0021] comminuting the mixed feed to form a comminuted feed stream;

[0022] floating at least most of the plastics in an overflow fraction while maintaining at least most of the comminuted tungsten-containing material and magnets in an underflow fraction; demagnetizing the comminuted magnets and optionally tungsten-containing material to form demagnetized comminuted magnets and optionally tungsten-containing material;

[0023] separating, by gravity separation, the comminuted tungsten-containing material from the demagnetized comminuted magnets;

[0024] recovering the rare earth elements from the separated comminuted magnets; and recovering the tungsten from the separated tungsten-containing material.

[0025] In aspects of the disclosure, a method can include the steps of:

[0026] receiving a mixed feed comprising tungsten-containing material in a nonferromagnetic portion and magnets in a ferromagnetic portion, wherein at least a portion of the magnets comprise rare earth elements;

[0027] comminuting the mixed feed to form a comminuted feed stream;

[0028] separating the comminuted tungsten-containing material in the non-ferromagnetic portion from the comminuted magnets in the ferromagnetic portion;

[0029] recovering the rare earth elements from the comminuted magnets in the ferromagnetic portion; and

[0030] recovering the tungsten from the tungsten-containing material in the nonferromagnetic portion.

[0031] In aspects of the disclosure, a method can include the steps of:

[0032] receiving a mixed feed comprising, in a ferromagnetic portion, tungsten-containing material and magnets, wherein at least a portion of the magnets comprise rare earth elements;

[0033] comminuting the mixed feed to form a comminuted feed stream;

[0034] recovering the rare earth elements from the comminuted magnets in the ferromagnetic portion; and

[0035] recovering the tungsten from the tungsten-containing material in the ferromagnetic portion.

[0036] In aspects of the disclosure, a method can include the steps of:

[0037] receiving a mixed feed comprising tungsten-containing material and magnets, wherein at least a portion of the magnets comprise rare earth elements, wherein the rare earth elements comprise one or more of neodymium, samarium, praseodymium, terbium, and dysprosium;

[0038] comminuting the mixed feed to form a comminuted feed stream; acid leaching the comminuted magnets in the presence of a tungsten solubilizing agent to form a pregnant leach solution comprising at least most of the one or more of neodymium, samarium, praseodymium, terbium, and dysprosium in the rare earth magnets and the tungsten in the tungsten-containing material and a leached residue; and recovering at least most of the rare earth elements and tungsten from the pregnant leach solution.

[0039] The present invention can provide a number of advantages depending on the particular configuration. The presented technology processes a variety of end-of-life devices to capture value from the content of the contained commodities. Such devices include, but are not limited to, haptic feedback modules in smart communication devices, such as phones, tablet computers, and watches.

[0040] These and other advantages will be apparent from the disclosure of the aspects, embodiments, and configurations contained herein.

[0041] As used herein, " at least one", "one or more", and "and / or" are open-ended expressions that are both conjunctive and disjunctive in operation. For example, each of the expressions "at least one of A, B, and C", "at least one of A, B, or C", "one or more of A, B, and C", "one or more of A, B, or C", " A, B, and / or C", and " A, B, or C" means A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B and C together. When each one of A, B, and C in the above expressions refers to an element, such as X, Y, and Z, or class of elements, such as X1-Xn, Y1-Ym, and Z1-Zo, the phrase is intended to refer to a single element selected from X, Y, and Z, a combination of elements selected from the same class (e.g., X1and X2) as well as a combination of elements selected from two or more classes (e.g., Y1and Zo).

[0042] It is to be noted that the term "a" or "an" entity refers to one or more of that entity. As such, the terms "a" (or "an"), "one or more" and "at least one" can be used interchangeably herein. It is also to be noted that the terms “comprising”, “including”, and “having” can be used interchangeably.

[0043] “Clumps,” “clumped material,” and the like refers to an aggregate composition (e.g., agglomerate, collection) of materials where the predominant force holding the materials together in the clump is magnetic attraction. The magnetic force causing the attraction results from the magnetic field applied by paramagnetic materials, ferromagnets, ferrimagnets, superparamagnetic materials, and other magnets in the clump. A “clump” of the present disclosure is predominantly composed of materials having magnetic properties, including magnetic and ferrous material (e.g., steel and ferromagnetic iron alloys), and in some embodiments, trace amounts (i.e., less than about 10 wt.%, less than about 5 wt.%, less than about 1 wt.%) of copper and aluminum.

[0044] “Electrochemical devices,” refers to device that generates electrical energy from chemical reactions and may include, but is not limited to, torches and flashlights, electrical appliances such as cellphones (long-life alkaline batteries), digital cameras (lithium batteries)

[0045] hearing aids (silver-oxide batteries), digital watches (mercury / silver-oxide batteries), military devices (thermal batteries), wind turbines, and power generators, and may otherwise be referred to as “electrochemical machinery,” “electrochemical equipment,” and the like.

[0046] “Ferromagnetic” refers to metals that can be magnetized. In their natural state, these metals are usually not magnetic themselves but will be attracted to objects which produce magnetic fields. When they are magnetized, they become magnets themselves. Non-limiting examples of ferromagnetic materials include cobalt, iron, ferric oxide, nickel, gadolinium, dysprosium, terbium, manganese, neodymium, and chromium dioxide.

[0047] “Haptic feedback” refers to the use of touch and vibrations to communicate sensations or feelings to a user. Haptic feedback is typically controlled vibrations at set frequencies and intervals to provide a target sensation to a user, such as bumps, knocks, and tap of one’s hands or fingers.

[0048] “Haptic technology (also kinaesthetic communication or 3D touch) is technology that can create an experience of touch by applying forces, vibrations, and / or motions to a user. These technologies, for example, can be used to create virtual objects in a computer simulation, to control virtual objects, and / or to enhance remote control of machines and devices (telerobotics). Haptic devices may incorporate tactile sensors that measure forces exerted by the user on the interface.

[0049] A “magnet” refers to an object made from magnetic materials and is capable of producing a magnetic field. A magnet may refer to an object currently producing a magnetic field or an object capable of being magnetized, such as demagnetized magnets. A magnet of the present disclosure may include permanent magnets, temporary magnets, electromagnets, or combinations thereof. Permanent magnets are typically naturally-occurring elements or chemical compounds that do not easily lose their magnetism. Nonlimiting examples of permanent magnets include neodymium iron boron (NdFeB), samarium cobalt (SmCo), aluminum-, cobalt- and nickel-comprising magnets (AlNiCo), and iron oxide- and / or barium-comprising magnets (e.g., ceramic, ferrite). Temporary magnets become magnetized when contacted with a magnetic field, but may lose their magnetism gradually as the field is removed. Electromagnetic magnets require an electric current to produce a magnetic field. “Magnets” of the present disclosure may include rare earth magnets and non-rare earth magnets.

[0050] “Magnetic material”, “magnetic component” or the like refers to materials capable of being affected by external electromagnetic fields in their surroundings. Magnetic materials of the present disclosure may include magnets, de-magnetized magnets, or magnetic metals not themselves capable of producing a magnetic field. Magnetic metals may include elemental metals such as iron, cobalt, nickel, boron, barium, gadolinium, dysprosium, neodymium, samarium, etc. and magnetic compounds such as steel, stainless steel, and other ferromagnetic iron alloys, ferrite, Alnico, Permalloy, etc. Magnetic materials used herein may include ferromagnetic metals, paramagnetic materials, diamagnetic materials, or combinations thereof.

[0051] A “mill” refers to any facility or set of facilities that process a metal-containing material, typically by recovering, or substantially isolating, a metal or metal-containing material from a feed material. Generally, the mill includes an open or closed comminution circuit, which includes crushers or autogenous, semi-autogenous, or non-autogenous grinding mills.

[0052] “Mixed feed” or the like, as used herein, refers to a feed of materials comprising magnetic or potentially magnetic materials, such as REE-comprising materials or magnets, non-REE materials or magnets, or a combination thereof. The magnetic materials in a mixed feed of the present disclosure may be operative, defective, whole, in pieces, demagnetized, or the like. The magnets may be free or unbound or may be contained within a larger part, such as discarded motors, discarded wind turbines, discarded magnetic resonance imaging machines, hard disk drives, meatballs, swarf, and other electromechanical waste. A mixed feed of the present disclosure may include materials that are or were recycled, scrap, trashed, discarded, reclaimed, recovered, salvaged, or the like

[0053] “Non-ferromagnetic” refers to materials that have little or no attraction to magnetic fields, such as wood, rubber, plastics, aluminum, copper, brass, gold, silver, titanium, tungsten, zinc, and lead. “Non-magnetic material,” “non-magnetic compounds,” or the like refers to materials that do not and will not produce a magnetic field on their own. By way of illustration, some non-magnetic metals and metal alloys, such as copper and aluminum are affected by changing magnetic fields that produce eddy currents in the metal that oppose the magnetic field of the source magnet. Non-limiting examples of non-magnetic materials include non-magnetic metals such as aluminum, copper, and gold, and other materials such as water, plastic, wood, rubber, etc.

[0054] “Non-rare earth magnets” may refer to any magnet that does not include rare earth elements including but not limited to aluminum-, cobalt- and nickel-comprising magnets (AlNiCo), and iron oxide- and / or barium-comprising magnets (e.g., ceramic, ferrite). Stated differently, non-rare earth magnets typically are substantially free of rare earth compounds and more typically comprise no more than about 0.1 wt.% rare earth compounds, and more typically no more than about 0.05 wt.% rare earth compounds.

[0055] “Target material” used herein, refers to tungsten and / or rare earth containing materials, such as from haptic or taptic engines and other components of electronic devices.

[0056] “Non-target materials” used herein, refers to non-magnetic materials (e.g., plastic, aluminum, copper, zinc) and non-target magnetic materials (e.g., steel and other ferromagnetic iron alloys).

[0057] “Para gnetism” refers to a form of magnetism whereby some materials are weakly attracted by an externally applied magnetic field, and form internal, induced magnetic fields in the direction of the applied magnetic field. Paramagnetism is due to the presence of unpaired electrons in the material, so most atoms with incompletely filled atomic orbitals are paramagnetic, although exceptions exist. Due to their spin, unpaired electrons have a magnetic dipole moment and act like tiny magnets. An external magnetic field causes the electrons' spins to align parallel to the field, causing a net attraction.

[0058] “Rare earth elements (REEs)” refers to lanthanides and scandium and yttrium. Specifically, REEs include lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), Erbium (Er), Thulium (Tm), ytterbium (Yb), lutetium (Lu), scandium (Sc), and yttrium (Y). REEs may otherwise be referred to as “rare earth metals”, “rare earths,” and the like. “Rare earth magnet” is a permanent magnet comprising one or more rare earth elements, typically in the form of alloys. The two primary types of rare earth magnets comprise neodymium magnets and samarium-cobalt magnets. A neodymium magnet (also known as NdFeB, NIB or Neo magnet) is a permanent magnet made from an alloy of neodymium, iron, and boron to form the Nd2Fe14B tetragonal crystalline structure and also comprising one or more of other REEs such as Pr, Dy, Tb etc.

[0059] A samarium-cobalt (SmCo) magnet is a permanent magnet made of two basic elements, namely samarium and cobalt and may comprise other REEs in small fraction. In embodiments, the rare earth compound(s) of the rare earth magnets of the present disclosure are substantially (e.g., at least about 20 wt.%, at least about 75 wt.%, at least about 90 wt.%, at least about 99 wt.%) composed of neodymium, samarium, terbium, dysprosium, praseodymium, and combinations thereof. In embodiments, the rare compound(s) of the rare earth magnets of the present disclosure comprise less about 10 wt.%, or more particularly less than about 5 wt.%, or more particularly less than about 2 wt.%, or more typically less than about 1 wt.% of lanthanum and cerium. Typically, a rare earth magnet comprises at least about 20 wt.% rare earth compounds, more typically at least about 25 wt.%, and even more typically at least about 30 wt.% rare earth compounds.

[0060] “Size reduction apparatus,” “size reduction device,” “comminuting apparatus,” “comminuting apparatus,” and the like referred to herein may be used interchangeably and are used herein to describe ball mills, hammer mills, rod mills, other known apparatuses used for size reduction techniques, and combinations thereof.

[0061] “Substantially free” as used herein, generally refers to compositions of less than about 25 wt.%, or more typically less than about 20 wt.%, or more typically less than about 15 wt.%, or more typically less than about 10 wt.%, or more typically less than about 5 wt.%, or more typically less than about 1 wt.%.

[0062] “Swarf’, as used herein, refers to pieces of metal that are debris or waste resulting from machining, or similar subtractive manufacturing processes and includes anything and everything related to magnet manufacturing and / or production waste or by-product that contains rare earth. Swarf can be small particles; long, stringy tendrils; slag-like waste; or dust.

[0063] “Target magnetic materials,” as used herein, refers to rare earth element(s) comprising magnets, such as but not limited to, neodymium magnets, samarium cobalt magnets, cobalt and / or nickel-comprising magnets such as, but not limited to aluminum nickel cobalt magnets, or any combination thereof.

[0064] “Tenacious” with reference to feed material may be refer to hard, or heavy materials, as compared to “tender” materials. Tenacious materials may include motors.

[0065] “Tender” with reference to feed material may be refer to soft materials as compared to “tenacious” materials. Tender materials may include HDDs.

[0066] Unless otherwise noted, all component or composition levels are in reference to the active portion of that component or composition and are exclusive of impurities, for example, residual solvents or by-products, which may be present in commercially available sources of such components or compositions.

[0067] All percentages and ratios are calculated by total composition weight, unless indicated otherwise.

[0068] The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Accordingly, the terms “including,” “comprising,” or “having” and variations thereof can be used interchangeably herein.

[0069] It should be understood that every maximum numerical limitation given throughout this disclosure is deemed to include each and every lower numerical limitation as an alternative, as if such lower numerical limitations were expressly written herein. Every minimum numerical limitation given throughout this disclosure is deemed to include each and every higher numerical limitation as an alternative, as if such higher numerical limitations were expressly written herein. Every numerical range given throughout this disclosure is deemed to include each and every narrower numerical range that falls within such broader numerical range, as if such narrower numerical ranges were all expressly written herein. By way of example, the phrase from about 2 to about 4 includes the whole number and / or integer ranges from about 2 to about 3, from about 3 to about 4 and each possible range based on real (e.g., irrational and / or rational) numbers, such as from about 2.1 to about 4.9, from about 2.1 to about 3.4, and so on.

[0070] The preceding is a simplified summary of the invention to provide an understanding of some aspects of the invention. This summary is neither an extensive nor exhaustive overview of the invention and its various embodiments. It is intended neither to identify key or critical elements of the invention nor to delineate the scope of the invention but to present selected concepts of the invention in a simplified form as an introduction to the more detailed description presented below. As will be appreciated, other embodiments of the invention are possible utilizing, alone or in combination, one or more of the features set forth above or described in detail below.

[0071] BRIEF DESCRIPTIONS OF THE DRAWINGS

[0072] The accompanying drawings are incorporated into and form a part of the specification to illustrate several examples of the present disclosure. These drawings, together with the description, explain the principles of the disclosure. The drawings simply illustrate preferred and alternative examples of how the disclosure can be made and used and are not to be construed as limiting the disclosure to only the illustrated and described examples. Further features and advantages will become apparent from the following, more detailed, description of the various aspects, embodiments, and configurations of the disclosure, as illustrated by the drawings referenced below.

[0073] FIG. 1 shows a simplified block diagram of a system for use in recycling materials including rare earth elements, from discarded motors, hard disk drives, and other waste in accordance with an embodiment;

[0074] FIG. 2 is a schematic diagram showing various physical components of an embodiment of a system for separating magnetic and nonmagnetic components;

[0075] FIG. 3 is a schematic diagram showing various physical components of another embodiment of a system for separating magnetic and nonmagnetic components;

[0076] FIG. 4 is a schematic diagram showing various physical components of another embodiment of a system for separating magnetic and nonmagnetic components;

[0077] FIG. 5 is a schematic diagram showing various physical components of another embodiment of a system for separating magnetic and nonmagnetic components having a belt-mounted magnetizer / demagnetizer;

[0078] FIG. 6 is a schematic block diagram of a process for producing a magnet concentrate by screening out clumps of magnet material in accordance with an embodiment and includes pictures of processed material with the magnetic clumps on the far left and progressively smaller size fractions to the right;

[0079] FIG. 7 is a flowchart of a specific process in accordance with one embodiment of the process of FIG. 6;

[0080] FIG. 8 is a schematic diagram showing various physical components of another embodiment of a system for separating magnetic and nonmagnetic components having a magnetic detector and a computing device for signal processing;

[0081] FIG. 9 is a block diagram of various physical elements of computer device of FIG.

[0082] 8;

[0083] FIG. 10 illustrates schematic block diagrams illustrating variations of embodiments involving selective calcination of a mixed oxalate;

[0084] FIG. 11 is a flowchart of a process combination used to output an enriched magnet concentrate from mixed scrap material;

[0085] FIG. 12 is a schematic illustration of an embodiment of a cleaning process of swarf; FIG. 13 is a flowchart of chemical processing steps used to convert a variety of magnet-containing feeds into a rare earth concentrate in one embodiment;

[0086] FIG. 14 is a flowchart of another embodiment of the process of FIG. 13, comprising additional steps;

[0087] FIGS. 15-17 depicted flow diagrams associated with the system of FIG. 1;

[0088] FIG. 18 is a flowchart of chemical processing steps used to convert a variety of magnet-containing feeds into a rare earth concentrate in one embodiment;

[0089] FIGS. 19-21 are charts depicting results of Examples 1 through 5 related to embodiments of the present disclosure;

[0090] FIG. 22 depicts the results of an11B NMR performed on a resulting solid produced from boron removal techniques related to embodiments of the present disclosure;

[0091] FIG. 23 is directed to a process according to an embodiment of the present disclosure;

[0092] FIG. 24 is directed to a process according to an embodiment of the present disclosure;

[0093] FIG. 25 is directed to a process according to an embodiment of the present disclosure;

[0094] FIG. 26 is directed to a process according to an embodiment of the present disclosure;

[0095] FIG. 27 is directed to a process according to an embodiment of the present disclosure;

[0096] FIG. 28 depicts a disassembled Taptic engine;

[0097] FIG. 29 depicts pie charts showing the content (wt.%) of a Taptic engine;

[0098] FIG. 30 is a plot of XRD peak (counts / s) (vertical axis) against position ([°29]); and FIG. 31 is a plot of leaching (%) (vertical axis) against constituent element (horizontal axis).

[0099] Unless otherwise specifically noted, articles depicted in the drawings are not necessarily drawn to scale.

[0100] DETAILED DESCRIPTION

[0101] The presented technology processes a variety of end-of-life devices to capture value from the content of the contained commodities. Such devices include, but are not limited to, electric motors, hard drives, speakers, compressors, electromagnetic imaging devices (e.g., magnetic resonance imaging (MRI) machine), meatball (partially deconstructed motors), other electromagnetic devices containing magnets, haptic engines, and any magnet-containing end-of-life products or any parts thereof.

[0102] In some embodiments, the present disclosure is directed to a methods and systems for recycling haptic modules in various electronic devices, such as portable electronic devices. The methods and systems can extract magnetic material and tungsten from haptic feedback modules of portable electronic devices. An exemplary system includes a size reduction unit for magnet and tungsten-containing material, such as taptic / haptic engines, electronic portable devices, or parts thereof, and outputting separated concentrated streams of magnetic components and tungsten by exploiting physical properties such as magnetic, size, density and chemical properties. The system can also include a selective chemical processing unit for receiving the magnetic components and tungsten scrap concentrate to extract rare earth elements and tungsten separately.

[0103] The processes of the present disclosure can recover valuable materials from haptic engines in various wearable and handheld devices. A haptic engine (which includes Taptic™ engines of some electronic devices) is a type of vibration motor that incorporates haptic feedback technology and uses a linear resonant actuator to create tactile sensations in the form of precise, localized vibrations for tactile responses on devices. Instead of a standard vibrating motor, a haptic engine can provide a more nuanced and realistic sensation, making the device feel like it has a physical button and / or causing the device to generate distinct taps for different notifications. A haptic engine can comprise a number of valuable metals, including without limitation from about 10 to about 65 wt.% tungsten alloy (with the major phase (more than 50 wt.%) being tungsten (W) and the minor phase (less than 50 wt.%) being an iron-nickel alloying element), from about 5 to about 35 wt.% rare earth element magnets containing rare earth elements (REEs), and from about 0.5 to about 10 wt.% copper. Other materials that may be included in the haptic engine include from about 15 to about 50 wt.% steel and from about 0.1 to about 3.5 wt.% plastic.

[0104] For simplicity and clarity of illustration, where considered appropriate, reference numerals may be repeated among the Figures to indicate corresponding or analogous elements. In addition, numerous specific details are set forth in order to provide a thorough understanding of the embodiment or embodiments described herein. However, it will be understood by those of ordinary skill in the art that the embodiments described herein may be practiced without these specific details. In other instances, well-known methods, procedures and components have not been described in detail so as not to obscure the embodiments described herein. It should be understood at the outset that, although exemplary embodiments are illustrated in the figures and described below, the principles of the present disclosure may be implemented using any number of techniques, whether currently known or not. The present disclosure should in no way be limited to the exemplary implementations and techniques illustrated in the drawings and described below.

[0105] Various terms used throughout the present description may be read and understood as follows, unless the context indicates otherwise: "or" as used throughout is inclusive, as though written "and / or"; singular articles and pronouns as used throughout include their plural forms, and vice versa; similarly, gendered pronouns include their counterpart pronouns so that pronouns should not be understood as limiting anything described herein to use, implementation, performance, etc. by a single gender; "exemplary" should be understood as "illustrative" or "exemplifying" and not necessarily as "preferred" over other embodiments. Further definitions for terms may be set out herein; these may apply to prior and subsequent instances of those terms, as will be understood from a reading of the present description. It will also be noted that the use of the term "a" or "an" will be understood to denote "at least one" in all instances unless explicitly stated otherwise or unless it would be understood to be obvious that it must mean "one".

[0106] Modifications, additions, or omissions may be made to the systems, apparatuses, and methods described herein without departing from the scope of the disclosure. For example, the components of the systems and apparatuses may be integrated or separated. Moreover, the operations of the systems and apparatuses disclosed herein may be performed by more, fewer, or other components and the methods described may include more, fewer, or other steps. Additionally, steps may be performed in any suitable order. As used in this document, "each" refers to each member of a set or each member of a subset of a set. Referring to Fig. 23, a method according to embodiments of the disclosure is depicted.

[0107] In step 2304, the end-of-life electronic device is disassembled to provide a subassembly comprising one or more haptic feedback modules contained in the device. Disassembly can be done manually and / or robotically, depending on the application. The resulting subassembly typically includes magnetic material (including ferromagnetic material) and tungsten-containing material.

[0108] The subassemblies containing the haptic feedback modules are comminuted by a size reduction apparatus, such as by one or more shredders, crushers, or mills to form a comminuted feed stream having a desired particle size (step 2308). Typically, the comminuted feed stream particles have a P80size between about 1 to about 100,000 microns, or more typically between about 5 to about 1,000, or more typically between about 10 to about 500 microns, or more typically between about 50 to about 250 microns, or more typically about 100 microns. The feed material to the process can be in the form of wearable and handheld devices, such as phones, watches, tablet computers, and the like that are comminuted to form the comminuted feed stream followed by separation of haptic engines from the comminuted scrap.

[0109] The comminuted feed stream 2312 is treated in a ferromagnetic material extraction block 2316 to provide separated non-ferromagnetic material fraction 2324 comprising most of the non-ferromagnetic materials comprising most of the non-magnetic material, such as aluminum, copper, tungsten or wolfram, plastics, and the like, in the comminuted feed stream and ferromagnetic material fraction 2332 comprising most of the magnetic material including most of the rare earth and non-rare earth magnetics in the comminuted feed stream.

[0110] The ferromagnetic material extraction block 2316 is described in Figures 1-5, 7-8, 11, and 15-16 below.

[0111] Fig. 1, is an overview of a simplified block diagram of system 10 for use in recycling materials including magnets, haptic engines, and rare earth elements, from discarded motors, hard disk drives, and other electromechanical waste.

[0112] As shown, system 10 includes a first subsystem 30 for receiving discarded waste 12 (e.g., motors, hard disk drives (HDDs), meatballs, haptic engines, and the like) and separating them into magnetic and non-magnetic components, and a second subsystem 32 for receiving a magnet concentrate from first subsystem 30 as well as swarf and defective magnets and for obtaining a rare earth element concentrate.

[0113] First subsystem 30 includes an optional size reduction block 14 and a target magnetic materials extraction block 16. Optional size reduction block 14 receives waste 12. Components of waste 12 may include rare earth element-comprising magnets, such as but not limited to, neodymium magnets, samarium cobalt magnets, cobalt and / or nickel-comprising magnets such as, but not limited to aluminum nickel cobalt magnets, or any combination thereof. Rare earth element-comprising magnets typically include one or more of iron, nickel, cobalt, neodymium, boron, aluminum, niobium, dysprosium, samarium, praseodymium, terbium, copper, barium, hafnium, zirconium, and manganese. In a nonlimiting example, neodymium magnets are primarily made with an alloy of neodymium (about 15 to about 30 wt.%), iron (about 65 to about 69 wt.%), and boron (about 1 wt.%) and may also have small amounts (i.e., less than about 5 wt.% total) of elements including praseodymium, dysprosium, terbium, and cobalt. In another non-limiting example, samarium cobalt magnets are primarily made with an alloy comprising samarium (about 35 wt.%) and cobalt (about 60 wt.%) and may also include small amounts (i.e., less than about 5 wt.%) of iron, copper, hafnium, zirconium, and praseodymium. Waste 12 may also include other ferromagnetic material such as tungsten-containing material, steel and other ferromagnetic iron alloys and non-ferromagnetic materials such as plastics, glass, aluminum and copper.

[0114] Tungsten-containing material may behave as a ferromagnetic or non-ferromagnetic material. As will be appreciated, tungsten can be part of ferroalloy e.g., Ferrotungsten (FeW) which is a metal alloy made of iron and tungsten having ferromagnetic properties and therefore be included in the ferromagnetic material fraction. Tungsten can also be part of a nonferroalloy, such as a Permalloy in which tungsten is the major phase and an ironnickel alloying element is a minor phase. Such alloys may not comprise sufficient iron to exhibit ferromagnetic behavior and therefore display non-ferromagnetic behavior. Such tungsten alloys will be part of the non-ferromagnetic material fraction.

[0115] The size reduction block 14 (which may perform step 2308) may receive the waste 12 in any size but typically ranging from about 0.5 to about 36 inches. Size reduction block 14 reduces the received waste 12 in size, in a controlled manner that is suitable for further processing, such that magnets are mostly preserved. In a non-limiting example, the size reduction block 14 comprises a mill, such as a hammer mill designed to grind, mill, and / or crush the received waste 12 to achieve the reduced size in a controlled manner. The size reduction block 14 reduces the size of at least most (i.e., at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 99% by mass) of the waste 12. Traditional crushing, smashing or pulverization of materials containing magnets in an uncontrolled environment may lead to loss of magnets, which may stick to surrounding objects or surfaces exhibiting ferromagnetic properties.

[0116] At target magnetic materials extraction block 16, target magnetic materials 24 are separated or extracted from the reduced material (or non-ferromagnetic material fraction 2324) at the output of block 14, as described in further detail below. Target magnet materials 24 include rare earth element(s) comprising magnets.

[0117] The target magnetic materials extraction block 16 may separately extract non-target materials 18 (or non-ferromagnetic material fraction 2324) and target magnetic materials 24. Non-target materials 18 include non-magnetic materials 18a (such as plastic, aluminum, copper, and the non-ferromagnetic fraction 2324) and non-target magnetic materials 18b such as steel and other ferromagnetic iron alloys and certain tungsten alloys in the ferromagnetic material fraction 2316).

[0118] In embodiments, at least about 75%, or more typically at least about 80%, or more typically at least about 85%, or more typically at least about 90%, or more typically at least about 95%, or more typically at least about 99%, or more typically at least about 99.5% by mass of the magnets from waste 12 are recovered in the target magnetic material 24.

[0119] In embodiments, the target magnetic materials 24 from subsystem 30 may be substantially free of non-target materials 18. That is, the target magnetic materials 24 from subsystem 30 may comprise less than about 25 wt.%, or more typically less than about 20 wt.%, or more typically less than about 15 wt.%, or more typically less than about 10 wt.%, or more typically less than about 5 wt.%, or more typically less than about 1 wt.% of non-target materials 18.

[0120] The non-target materials 18 may be substantially depleted of rare-earth comprising magnets and / or elements. In embodiments, the non-target materials 18 may comprise less than about 20 wt.%, or more typically less than about 15 wt.%, or more typically less than about 10 wt.%, or more typically less than about 5 wt.%, or even more typically less than about 1 wt.%, rare-earth comprising magnets and / or elements.

[0121] In embodiments, the non-target magnetic materials 18b is separated from and is substantially free of non-magnetic materials 18a, i.e., comprising less than about 10 wt.%, or more typically less than about 5 wt.%, or more typically less than about 3 wt.%, or even more typically less than about 1 wt.% non-magnetic materials 18a. In embodiments, the non-magnetic materials 18a and non-target magnetic materials 18b are combined in nontarget materials 18. Non-target materials 18 may include forms of steel and other ferromagnetic iron alloys, copper, aluminum, and certain tungsten alloys not exhibiting ferromagnetic behavior, and plastics and non-metallics.

[0122] System 10 also includes a second subsystem 32, that is an example of an embodiment of the present disclosure, for receiving discarded waste and / or by-products 20 in the form of swarf, defective and / or magnets that are not usable in their current state. Discarded waste 20 is substantially free (i.e., comprising less than about 50 wt.%, less than about 25 wt.%, less than about 15 wt.%, less than about 10 wt.%, or less than about 5 wt.%, or less about 1 wt.%) of non-target materials including non-magnetic materials 18a (such as but not limited to plastic, aluminum, copper) and non-target magnetic materials 18b such as steel and other ferromagnetic iron alloys. Discarded waste 20 may be input to milling / washing block 22.

[0123] A milling / washing block 22 receives the swarf, defective magnets, and / or currently unusable magnets, and outputs target magnetic material 24. In embodiments, milling / washing block 22 occurs in subsystem 30 and / or subsystem 32. If milling / washing block 22 is included in subsystem 30, the milling / washing block 22 may be included prior to or after size reduction unit 14. Additionally or alternatively, the milling / washing block 22 may occur prior to or after target magnetic materials extractions block 16. Additionally or alternatively, a milling / washing block 22 in subsystem 30 may occur in parallel to the size reduction unit 14 and / or target magnetic materials extraction block 16, and the milled and / or washed material from the milling / washing block 22 may be combined with the output of block 16 to produce target magnetic materials 24. If milling / washing block 22 is included in subsystem 32, the milling / washing block 22 may be configured to receive swarf, defective magnets and / or currently unusable magnets from block 20 and output target magnetic materials 24.

[0124] Target magnetic materials 24 may include diamagnetic, ferromagnetic, and paramagnetic metal-comprising components. As used in this document, target magnetic material includes rare earth element(s) containing magnets, such as but not limited to neodymium magnets, samarium cobalt magnets, cobalt and / or nickel containing magnets such as, but not limited to aluminum nickel cobalt magnets, or any combination thereof. Target magnetic materials 24 may include certain tungsten alloys exhibiting ferromagnetic behavior. In embodiments, swarf may not require milling and may bypass milling / washing block 22 and be presented directly as forming part of target magnetic materials 24. Defective magnets and large magnets may or may not require demagnetizing before being provided to milling / washing block 22.

[0125] Target magnetic materials 24 may therefore result from one or both target magnetic materials extraction block 16 of subsystem 30 and milling / washing block 22 of subsystem 32. As depicted in FIG. 1, some or all of the target magnetic materials 24 may also be obtained directly from swarf and unusable magnets in discarded waste 20 without necessarily going through the milling block 22. In embodiments, the target magnetic materials 24 from subsystem 30 and / or subsystems 32 may be substantially free of nontarget materials (e.g., plastic, aluminum, copper, steel and other ferromagnetic iron alloys). That is, the target magnetic materials 24 from subsystem 30 may comprise less than about 60 wt.%, or more typically less than about 25 wt.%, or more typically less than about 15 wt.% or more typically less than about 10 wt.%, or more typically less than about 5 wt.%, or more typically less than about 1 wt.% of non-target materials.

[0126] In embodiments, the target magnetic materials 24 from subsystem 30 and / or subsystems 32 may be substantially uniform in size.

[0127] The target magnetic materials 24 are further processed in a chemical processing block 26, as described in more detail below, to obtain one or more rare earth element and transition metal concentrates 28. Chemical processing block 26 may include sub-blocks for hydrometallurgical and non-hydrometallurgical steps. The one or more concentrates 28 may include, for example, a rare earth element concentrate, cobalt and / or a nickel concentrate, a tungsten concentrate, and a boron concentrate in elemental form and / or as compounds (e.g., rare earth oxides, nickel cobalt hydroxide).

[0128] Several embodiments of systems and / or methods for separating valuable magnet materials are described in the present disclosure, with reference to several specific embodiments, as disclosed below.

[0129] Embodiment 1 - Separation of magnets from steel and other ferromagnetic iron alloys and non-ferromagnetic material using a ferromagnetic gathering surface. According to a first set of embodiments, there are provided systems and methods of separating magnets from steel and other materials exhibiting ferromagnetic behavior using a ferromagnetic gathering surface. It is well known that magnetized material is attracted to ferromagnetic iron alloys. In one embodiment, this property is exploited to selectively sort magnets from mixed scrap material including from ferrous material (e.g., steel and other ferromagnetic iron alloys).

[0130] In one embodiment, illustrated in FIG. 2, milling is used to form small discrete components of consistent size of a mixed scrap 23 which include non-magnetized components 23a and magnetized components 23b. Non-magnetized components 23a may refer to non-target materials 18 as described with reference to FIG. 1 and may include plastic, rubber, glass, non-magnetic metals such as aluminum and copper, steel, tungsten-containing alloys, and other ferromagnetic iron alloys etc., or combinations thereof. Magnetized components 23b may refer to target magnetic materials 24 as described with reference to FIG. 1 and may comprise rare earth element(s)-comprising magnets, such as but not limited to neodymium magnets, samarium cobalt magnets, cobalt and / or nickel-comprising magnets such as, but not limited to aluminum nickel cobalt magnets, or any combination thereof. The mixed scrap 23 may comprise any ratio of non-magnetized components 23a to magnetized components 23b.

[0131] The components of mixed scrap 23 are conveyed along a non-ferromagnetic conveyor belt such as a rubber belt, which passes underneath, and may be in physical contact with, a rotating or revolving steel or other ferromagnetic iron alloy drum 25. The conveyor belt may move at a substantially consistent speed. The steel or other ferromagnetic iron alloy drum may move at a substantially consistent speed. In embodiments, the steel or other ferromagnetic iron alloy drum may rotate at a same or similar speed to the conveyor belt. In embodiments, the steel or other ferromagnetic iron alloy drum may rotate at different speed to the conveyor belt. The steel or other ferromagnetic iron alloy drum may rotate in the opposite direction to the conveyor belt. In the example depicted in FIG. 2, the conveyor belt rotates clockwise and the steel or other ferromagnetic iron alloy drum rotates counter clockwise to carry the magnetized components away from the conveyor belt and nonmagnetized components 23 a. The magnetized components stick to the drum and are scraped off for collection by a scraper 27. The scraper 27 may be substantially fixed or immobile.

[0132] The non-magnetized components 23a may be discharged from the conveyor belt into a first storage unit (e.g., containers, bins) and the magnetized components 23b (which are magnetically attracted to and in contact with the steel or other ferromagnetic iron alloy drum) may be scraped from the steel or other ferromagnetic iron alloy drum 25 into a second storage unit. The first storage unit may be substantially free of magnetized components 23b. That is, the composition of components in the first storage unit typically comprises less than about 10%, or more typically less than about 5%, or even more typically less than about 1% by mass of magnetized components 23b. The second storage unit typically comprises at least about 50 wt.%, more typically at least about 75 wt.% and more typically at least about 85 wt.% of the tungsten-containing alloys in the mixed scrap 23.

[0133] The embodiment depicted in FIG. 2 is highly efficient such that the second unit captures substantially all the magnetized components 23b that enter onto the conveyor. That is, less than about 25%, or more typically less than about 10%, or even more typically less than about 5% by mass of the magnetized components 23b that are placed onto the conveyor are discharged into the first unit or are otherwise lost (i.e., not discharged in the second unit). The composition of components in the second unit is substantially free of nonmagnetized components 23a. That is, non-magnetized components 23a comprises less than about 50%, or more typically less than about 40%, or more typically less than about 30%, or more typically less than about 20%, or more typically less than about 10%, or more typically less than about 5% by mass of the total component composition stored in the second unit. Stated differently, the magnetized components 23b comprise at least about 50%, or more typically at least about 90%, or even more typically at least about 95% by mass of the total component composition stored in the second unit.

[0134] Elements of FIG. 2, including but not limited to the speed of the belt, the speed of the drum 25, the position of the scraper 27 relative to the drum and / or relative to the storage units, the size of the mixed scrap 23, the size of the storage units, the placement or distance of the storage units from the conveyor and / or scrapper 27, the distance between storage units, the width of the conveyor belt, the width of the drum 25, etc. are designed to achieve a high efficiency separation of magnetized components 23b from the scrap 23, and / or a high degree of capture of the magnetized components 23b into the second storage unit. In embodiments, the elements of FIG. 2 are designed so as to separate at least most (i.e., at least about 50%, at least about 75%, at least about 85%, at least about 90%, at least about 95%, at least about 99% by mass) of the magnetized components 23b from the nonmagnetized components 23a for discharge into separate storage units.

[0135] In another embodiment, illustrated in FIG. 3, a mixed scrap 33 containing nonmagnetized components 33a and magnetized components 33b is conveyed on a variable speed thin non-ferromagnetic belt (e.g., rubber belt) conveyor 36. At the end of the conveyor 36 the belt passes over a steel or other ferromagnetic iron alloy idler 35 that exerts passive attraction on any magnetized components 33b within the mixed scrap 33. As a result of the magnetic force of attraction, magnetized components 33b are thrown a shorter distance off the belt, whereas non-magnetized material is thrown further, allowing the discrete components of the material to be sorted into magnetized and non-magnetized components within two bins 37, 38 respectively.

[0136] The relative magnitude of this effect can be controlled by varying the speed of the belt, the thickness of the belt, the size of the mixed scrap 33, or combination thereof. The belt conveyor 36 and idler 35 may operate at substantially the same speeds. In embodiments, the speed and thickness of the belt conveyor 36 and / or idler 35 may be based on the magnetic force to be applied to the magnetized components 33b, the magnetic force of the idler 35, or both. In embodiments, the magnetized components 33b typically travel a horizontal distance on the conveyor 36 to bin 37. In embodiments, the non-magnetized components 33a typically travel a horizontal distance from the conveyor 36 to bin 38.

[0137] Elements of FIG. 3, including but not limited to the speed of the belt, the thickness of the belt, the size of the mixed scrap 33, the size of the bins 37 and 38, the placement or distance of the bins 37 and 38 from the conveyor 36, the distance between bins 37 and 38, the width of the conveyor 36, the width of the idler 35, etc. are designed to achieve a high efficiency separation of magnetized components 33b from the scrap 33, and / or a high degree of capture of the magnetized components 33b into bin 37. In embodiments, the elements of FIG. 3 are designed so as to separate at least most (i.e., at least about 50%, at least about 75%, at least about 85%, at least about 90%, at least about 95%, at least about 99% by mass) of the magnetized components 33b from the non-magnetized components 33a for discharge into separate bins.

[0138] In an example, elements of FIG. 3 are designed so that the horizontal distances traveled by the non-magnetized components 33a and the magnetized components 33b do not overlap or separated by a sufficient difference. In a specific non-limiting example, the process of FIG. 3 may be configured so the non-magnetized components 33a travel from about 2 inches to 5 feet from the conveyor 36 and the magnetized components 33b travel from about 0.5 inches to about 2 feet from the conveyor 36.

[0139] The embodiment depicted in FIG. 3 is highly efficient such that the magnet bin 37 captures substantially all the magnetized components 33b that enter onto the conveyor 36. That is, less than about 25%, or more typically less than about 15%, or even more typically less than about 5% by mass of the magnetized components 33b that are placed onto the conveyor 36 are discharged into bin 38 or are otherwise lost (i.e., are not discharged into bin 37). The composition of components in bin 37 is substantially free of non-magnetized components 33a. That is, non-magnetized components 33a comprises less than about 50%, or more typically less than about 25% or more typically less than about 10% by mass of the total component composition stored in bin 37. Stated differently, the magnetized components 33b comprise at least about 50%, or more typically at least about 75%, or even more typically at least about 90% by mass of the total component composition stored in bin 37.

[0140] The non-magnet bin 38 may be substantially free of magnetized components 33b and typically contains at least most and more typically at least about 65 wt.% of the tungsten-containing alloys. That is, the composition of components in the non-magnet bin 38 comprises less than about 10%, or more typically less than about 5%, or even more typically less than about 1% by mass of magnetized components 33b. In another embodiment depicted in FIG. 4, mixed scrap 33 (such as that described with reference to FIG. 3) is configured to slide down a gently sloped vibrating steel or other ferromagnetic iron alloy plate of an otherwise non-ferromagnetic hopper (e.g., non-steel or other ferromagnetic iron alloy hopper). Magnetized components 33b are attracted to the steel or other ferromagnetic iron alloy plate and therefore slide more slowly than non-magnetized components 33a. The discrete components of the material partitions into two cuts, one enriched in magnets.

[0141] The slope of the steel or other ferromagnetic iron alloy plate may range from about 30° to about 85°, or more typically from about 45° to about 80°, or more typically from about 50° to about 75°, or more typically from about 55° to about 70°, relative to a horizontal surface.

[0142] The non-magnetized components 33a may be discharged from the steel or other ferromagnetic iron alloy plate into a first storage unit (e.g., containers, bins) and the magnetized components 33b may be scraped or removed from the steel or other ferromagnetic iron alloy collection bands by any means to form a magnetized component concentrate. The first storage unit may be substantially free of magnetized components 33b. That is, the composition of components in the first storage unit comprises less than about 10%, or more typically less than about 5%, or even more typically less than about 1% by mass of magnetized components 33b.

[0143] The magnetized component concentrate may capture substantially all the magnetized components 33b that enter into the hopper. That is, less than about 10%, or more typically less than about 5%, or even more typically less than about 1% by mass of the magnetized components 33b that are placed onto the hopper are discharged into the first unit or are otherwise lost. The composition of the magnetized component concentrate is substantially free of non-magnetized components 33a. That is, non-magnetized components 33a comprises less than about 50%, or more typically less than about 25% or more typically less than about 10% by mass of the total magnetized component concentrate composition. Stated differently, the magnetized components 33b comprise at least about 50%, or more typically at least about 75%, or even more typically at least about 90% by mass of the total magnetized component concentrate composition.

[0144] Elements of FIG. 4, including but not limited to the slope of the plate, the vibration of the plate, the size or configuration of the hopper, the material of the hopper, the method of removing the magnetized components 33b from the hopper, the size of the mixed scrap 33, etc. are designed to achieve a high efficiency separation of magnetized components 33b from the scrap 33, and / or a high degree of capture of the magnetized components 33b. In embodiments, the elements of FIG. 4 are designed so as to separate at least most (i.e., at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 99% by mass) of the magnetized components 33b from the nonmagnetized components 33 a.

[0145] Non-magnetized components 33a of FIGs. 3 and 4 may refer to non-target materials 18 as described with reference to FIG. 1 and may include plastic, rubber, glass, nonmagnetic metals such as aluminum and copper, steel and other ferromagnetic iron alloys, tungsten-containing alloys, etc., or combinations thereof. Magnetized components 33b may refer to target magnetic materials 24 as described with reference to FIG. 1 and may comprise rare earth element(s)-comprising magnets, such as but not limited to neodymium magnets, samarium cobalt magnets, cobalt and / or nickel-comprising magnets such as, but not limited to aluminum nickel cobalt magnets, or any combination thereof.

[0146] The mixed scrap 33 may comprise any ratio of non-magnetized components 33a to magnetized components 33b.

[0147] A ferromagnetic "collection band" is then added as a collection point for lightweight magnetic particles, such as particles less than about 500 grams, or more typically less than about 400 grams, or more typically less than about 300 grams, or more typically less than about 200 grams, or more typically less than about 100 grams. The magnetic particles are harvested. In embodiments, the magnetic particles are harvested with a scraper, though the magnetic particles may be removed from the band by any means. The magnetic particles may be removed from the band periodically (i.e., at recurring in time intervals), or as needed (i.e., the collection band is substantially at capacity by weight, surface area, etc.).

[0148] The above embodiments may be enhanced by ensuring that there are no competing ferromagnetic surfaces for the magnetic components from the mixed scrap to adhere to. This may involve, for example, replacing steel and other ferromagnetic iron alloy conveyor belt rollers with nylon rollers, replacing steel and other ferromagnetic iron alloy chutes with fiberglass chutes, and replacing carbon steel mechanical parts with stainless steel parts. Adjacent equipment such as mills, conveyors, chutes and storages may be modified or redesigned accordingly.

[0149] In some embodiments, fragmented magnets may be too weakly magnetic to be sufficiently attracted to a steel surface or plate, even if the fragmented magnets come into direct contact. Moreover, a significant amount of bulk ferrous material may follow the magnets. In such cases, the embodiments may be used for partial upgrading step of the scrap mix, which will further be processed.

[0150] Embodiment 2 - Use of demagnetization and re-magnetization to separate magnets from steel and other ferromagnetic iron alloys and non-ferromagnetic materials As noted above, magnetized material is attracted to ferromagnetic iron alloys such as steel and tungsten-containing alloys. Accordingly, in a conventional scrap processing line, the magnetic components follow the steel and other ferromagnetic iron alloys and tungsten-containing alloys through the process. In sharp contrast to conventional scrap processing, in one embodiment, the magnetic components are demagnetized, and subsequently separated from steel and other ferromagnetic iron alloys and tungsten-containing alloys by exploiting their other properties, such as size and / or density, or differences in hardness.

[0151] A magnet can be demagnetized to reduce or remove substantially magnetic properties from the magnet, such as the magnetic field strength (H). According to embodiments herein, a magnet can be partially, mostly, or substantially completely demagnetized thermally, physically, electromagnetically, and / or over time. In embodiments, the magnets are demagnetized as a bi-product to processing disclosed herein such as milling. In embodiments, separation procedures disclosed herein may include a demagnetization step.

[0152] A demagnetization method may include heating a magnet to a high temperature, such as the Curie temperature of the magnet, for a period of time. A magnet will lose at least part of and typically most of its magnetic field strength and may become partially, mostly, or substantially completely demagnetized permanently if exposed to a temperature near or above its maximum operating temperature for a period, or if heated above its Curie temperature (i.e., the temperature at which all magnetization of the magnet is permanently lost). In between the maximum operating temperature and the curie temperature, some percentage of the magnetization is irreversibly lost. By way of example, neodymium-comprising magnets (e.g., NdFeB magnets) typically have a maximum operating temperature of about 150°C and have a Curie temperature ranging from about 310-400°C. Samarium cobalt magnets can typically withstand operating temperatures of up to about 310°C, and have a Curie temperature ranging from about 700-800°C. Alnico magnets can typically operate at temperatures up to about 525°C and have a Curie temperature of about 800°C. Ferrite (ceramic) magnets typically have a maximum operating temperature of about 250°C and a Curie temperature of around 450°C.

[0153] Other example demagnetization methods include dropping the magnet frequently, apply a hammering action or other force to the magnet repeatedly, bringing the magnet in contact with the like poles of other magnets repeatedly, passing an electric current through the magnet, leaving the poles of the magnets bare for a long duration (i.e., selfdemagnetization), exposure to an oscillating diminishing magnetic field, etc. Multiple demagnetization techniques may be applied in combination.

[0154] In one embodiment depicted in FIG. 5, the mixed scrap material 53, which may refer to mix scrap 23 and / or 33 of the above-referenced FIGs. is passed through a demagnetizing device arranged around a conveyor belt that applies a magnet field to the magnets to rearrange the polarity of the particles of the magnets. As depicted in FIG. 5, the demagnetizing device may include one or more pads installed, above, underneath, and / or on the sides of the conveyor belt. In a variation of the above embodiment, the mixed scrap material (23 or 33) is passed through an electric demagnetizing cylinder (e.g., a solenoid). The demagnetizing device may apply an oscillating, diminishing magnet field to demagnetize partially, mostly or substantially completely the mixed scrap 23 and / or 33. In embodiments, the demagnetizing device may include a rotating drum. The rotating drum may demagnetize (or at least partially reduce the magnetic field strength of) the magnets using magnetic fields. That is, the rotating drum may be magnetic or may otherwise be capable of applying a magnetic field.

[0155] In another variation of the above embodiment, the mixed scrap material is passed through a heating furnace. The heating furnace may apply a temperature ranging from about 50°C to about 1,000°C, and more typically from about 200 to about 800°C, or more typically from about 300 to about 600°C, or even more typically from about 350 to about 450°C, based on the magnet composition of the mixed scrap material 53 and whether the demagnetization is to be permanent or reversible.

[0156] A demagnetization process, as described herein, demagnetizes at least most of the magnetized magnets in the mixed scrap. That is, the demagnetization process demagnetizes at least about 75%, or more particularly at least about 80%, or more particularly at least about 85%, or more particularly at least about 90%, or more particularly at least about 95%, or even more particularly at least about 99% by mass of the magnets comprising a magnetic field in the mixed scrap.

[0157] After demagnetization, the field strength of the magnets may be reduced by at least about 50%, or more particularly by at least about 60%, or more particularly by at least about 70%, or more particularly by at least about 80%, or more particularly by at least about 90%, or more particularly by at least about 95%, or even more particularly by at least about 99%. In embodiments, the mixed scrap, prior to demagnetization, includes magnetized magnets and magnets that have already been demagnetized (e.g., the net magnetic field of the magnets has been substantially reduced to zero or is negligible). The demagnetization process as described herein may have no further effect on the demagnetized magnets.

[0158] The resulting demagnetized material is then subjected to a downstream separation method. The downstream separation process may be able to distinguish between magnetic materials, allowing for the separation of ferrite magnets, tungsten-containing alloys, and / or steel and other ferromagnetic iron alloys. According to this embodiment, the downstream separation process exploits the magnetic properties of steel, tungsten-containing alloys, and other ferromagnetic iron alloys versus the magnets.

[0159] In the embodiment depicted in FIG. 5, re-magnetization of demagnetized magnets may be used. Ferromagnetic material can be magnetized by exposing it to a magnetic field. Material magnetized in this way may retain or recover at least in part and typically at least most of its magnetism permanently or temporarily (e.g., magnetism is retained for a length of time, or for an amount of use and may be based on storage, type of use, etc.). In one embodiment, a mixed stream 53 of non-ferrous material containing an amount of unmagnetized (i.e., demagnetized) magnet material 53b is re-magnetized. The re-magnetized magnets 53c are then selectively pulled from the mixed stream 53 using a ferromagnetic gathering surface, as described above.

[0160] A magnetization device, as described herein, magnetizes (or re-magnetizes) at least most of the magnets in the mixed scrap 53. That is, the magnetization process magnetizes at least about 75%, or more particularly at least about 80%, or more particularly at least about 85%, or more particularly at least about 90%, or more particularly at least about 95%, or even more particularly at least about 99% by mass of the magnets in the mixed scrap 53.

[0161] The magnetizing device may restore the magnetic field strength of the magnets to at least about 60%, or more particularly at least about 65%, or more particularly at least about 70%, or more particularly at least about 75%, or more particularly at least about 80%, or more particularly at least about 85%, or more particularly at least about 90%, or more particularly at least about 65%, or even more particularly at least about 99% of the original field strength of the magnets prior to demagnetization. That is, the demagnetization and / or magnetization process are designed so as to reduce the permanent damage incurred by the magnets. The downstream separation processes may separate at least most, such as at least about 75%, or more particularly at least about 80%, or more particularly at least about 85%, or more particularly at least about 90%, or more particularly at least about 95%, or even more particularly at least about 99% by mass of ferrite magnets, tungsten-containing alloys and / or steel and other ferromagnetic iron alloys from the desired magnets. Stated differently, a composition of a magnet concentrate produced by the downstream separation processes may comprise less than about 20%, or more typically less than about 15%, or more typically less than about 10%, or more typically less than about 5%, or even more typically less than about 1% by mass of ferrite magnets, tungsten-containing alloys, and / or steel and other ferromagnetic iron alloys 1.

[0162] In embodiments, the magnetizing device may including a rotating drum. The rotating drum may be magnetic or may otherwise be capable of applying a magnetic field and may therefore (re)magnetize the magnets when they contact the rotating drum. The rotating drum may be equipped with an alternating magnetic field for magnetization. In embodiments, the rotating drum may be used to separate magnets from non-magnetic material (e.g., copper, steel and other ferromagnetic iron alloys). For example, magnets (such as those remagnetized by the drum) and non-magnetic material may contact the rotating drum and leave (e.g., fall off, scrapped off) the drum differently based on the differing attraction of the magnets and non-magnetic material to the rotating drum.

[0163] A single device may be used for both de-magnetization and re-magnetization, as described with reference to FIG. 5. In one example, a single de-magnetization / magnetization device may be followed by the downstream separation process and the separated magnets may be reprocessed through the de-magnetization / magnetization device to be magnetized. Alternatively, different devices may be used for de-magnetization versus re-magnetization. In one example, a de-magnetization device may be followed by the downstream separation process and the separated magnets may proceed forward through a magnetization device (separate from the de-magnetization device) for magnetization.

[0164] Embodiment 3 - A method to create a magnet-enriched concentrate from steel or other ferromagnetic iron alloys -comprising scrap by milling, re-magnetizing / de-magnetizing, clumping, and screening

[0165] In another embodiment, a method of creating a magnet-enriched concentrate from tungsten-containing alloys, steel or other ferromagnetic iron alloys -comprising scrap is provided.

[0166] Steps of this embodiment exploit the physical properties of magnetic materials disclosed herein versus non-magnetic materials, and particularly tungsten-containing alloys, steel and other ferromagnetic iron alloys. In one non-limiting example, magnets or pieces of magnets attract ferromagnetic material such as tungsten-containing alloys, steel and other ferromagnetic iron alloys. If mixed scrap that contains magnets, tungsten-containing alloys and steel and other ferromagnetic iron alloys is milled to a small size, the small pieces of magnets will attract pieces of tungsten-containing alloys, steel, and other ferromagnetic iron alloys and ferromagnetic iron dust to form a larger, loosely-bound, clump of material. The magnet material concentrates inside the clumps, while the surrounding matrix material becomes relatively depleted of magnets. A magnet concentrate can be produced by screening out the clumps.

[0167] Steel and other ferromagnetic iron alloys and tungsten-containing alloys are generally substantially less brittle than rare earth element-comprising materials. As such, when a size reduction process is applied, rare earth element-comprising materials will reduce in size faster and more uniformly than steel and other ferromagnetic iron alloys and tungsten-containing alloys. That is, rare earth element-comprising materials will have a faster rate of size reduction than steel and other ferromagnetic iron alloys and tungsten-containing alloys. Therefore, size reduction and separation techniques may be combined that exploit the rate of size reduction associated with rare earth element-comprising materials versus steel and other ferromagnetic iron alloys and tungsten-containing alloys to achieve separation and produce a REE magnet concentrate. A schematic block diagram of an embodiment of the process is illustrated in FIG. 6.

[0168] In one specific embodiment, a process 700 depicted in FIG. 7, may involve one or more of the illustrated steps to form a magnet concentrate from mixed scrap. The mixed scrap may comprise non-magnetized components and magnetized components. Nonmagnetized components may refer to non-target materials 18 as described with reference to FIG. 1 and may include plastic, rubber, glass, non-magnetic metals such as aluminum and copper, tungsten-containing alloys, steel and other ferromagnetic iron alloys, etc., or combinations thereof. Magnetized components may refer to target magnetic materials 24 as described with reference to FIG. 1 and may comprise rare earth element(s)-comprising magnets, such as but not limited to neodymium magnets, samarium cobalt magnets, cobalt and / or nickel-comprising magnets such as, but not limited to aluminum nickel cobalt magnets, or any combination thereof. The mixed scrap may comprise any ratio of nonmagnetized components to magnetized components.

[0169] At step 701, the mixed scrap material comprising magnets is milled by a milling apparatus (e.g., a hammer mill) to a pre-determined size or for a pre-determined time. Components of the mixed scrap may be milled to achieve an average particle size ranging from about 5 inches and about 0.5 mm, or more particularly between about 4 inches and about 1 mm, or even more particularly between about 3 inches and about 1 cm. In a specific embodiment, the mixed scrap may be milled to achieve 80% passing of about 2 inches.

[0170] At step 702, a dust collection system may be utilized over the mill to capture dust generated by the milling process. The dust collection system may collect at least about 50%, or more particularly at least about 60%, or more particularly at least about 70%, or more particularly at least about 80%, or more particularly at least about 90%, or more particularly at least about 95%, or even more particularly at least about 99% by mass of the dust generated by the milling process.

[0171] In embodiments, milling may substantially de-magnetize magnets due to the force applied by the milling apparatus. In embodiments, between about 50% and about 100% by mass of the magnets in the mixed scrap may be de-magnetized, such that the magnetic field of the magnets is zero or negligible.

[0172] As an optional third step 703, the milled material may then be re-magnetized by passing it over or through a re-magnetizing device or by passing it over a magnetic field as described above. In one embodiment, the re-magnetizing device may be a magnet, which may be a strong magnet, such a neodymium magnet, and the step of re-magnetizing may include passing the material over a re-magnetizing device or the magnet.

[0173] The re-magnetizing device, as described herein, magnetizes (or re-magnetizes) at least some of the magnets in the mixed scrap.

[0174] An optional fourth step 704 involves shaking or vibrating the milled material to promote mixing, such that the magnet pieces form clumps. The shaking may be done in a gentle manner. The shaking may be performed by an agitator, a vibrating plate, a conveyor belt, etc. In some embodiments, the clumps may form without a separate shaking or vibrating step 704. The clumps may range in size and shape. In embodiments, the clumps may comprise an average diameter greater than about 2 inches, or more typically greater than about 3 inches, or more typically greater than about 4 inches, or more typically greater than about 5 inches, or more typically greater than about 6 inches. In embodiments, the clumps may comprise an average diameter ranging from about 2 inches to about 10 inches.

[0175] The clumps may comprise magnetic components, such that the clumps may be composed of at least about 10%, or more typically at least about 30%, or more typically at least about 50%, or more typically at least about 80%, or more typically at least about 90%, or even more typically at least about 95% by mass target magnetic components. Stated differently, the clumps may be composed of less than about 90%, or more typically less than about 70%, or more typically less than about 50%, or more typically less than about 20%, or more typically less than about 10%, or more typically less than about 5% by mass non-magnetized and non-target magnetic components, such as tungsten-containing alloys, steel and other ferromagnetic iron alloys.

[0176] At least about 10%, or more particularly at least about 30%, or more particularly at least about 50%, or more particularly at least about 80%, or more particularly at least about 90%, or more particularly at least about 95% by mass of the magnetized components of the mixed scrap may be captured in the clumps. Stated differently, less than about 90%, or more particularly at least about 70%, or more particularly at least about 50%, or more particularly at least about 20%, or more particularly at least about 10%, or more particularly at least about 5% by mass of the magnetized components do not form a clump and falls below the passing size of a first screen of step 705.

[0177] At a fifth step 705, the material comprising clumps and non-clumping components may then be passed over a set of screens progressively smaller in mesh size to produce several product fractions of progressively smaller components. In the depicted embodiment, two screens are used to produce three fractions. However, more generally, in other embodiments, N screens may be used to produce N+l fractions. The order of these steps may be different than the example embodiment described.

[0178] In one specific embodiment, screens are used to produce three product fractions, namely: an oversize fraction containing magnet-comprising clumps; a mid-size fraction comprising scrap metal depleted in magnets; and a fine fraction (dust).

[0179] In embodiments, one or more of the screen sizes may be selected based on the average size of the clumps and / or non-clumping components. The first screen may capture at least most (i.e., at least about 75%, or at least about 80%, or at least about 85%, or at least about 90%, or at least about 95%, or at least about 99%) of the clumps by mass. The first screen may allow at least most of the non-clumping components to pass to the second screen. That is, the composition of the material captured by the first screen may comprise less than about 20%, or more typically less than about 15%, or more typically less than about 10%, or more typically less than about 5%, or more typically less than about 1% nonclumping components by mass. Stated differently, the composition of the material captured by the first screen comprises greater than about 80%, or more typically greater than about 85%, or more typically greater than about 90%, or more typically greater than about 95%, or more typically greater than about 99% magnet-comprising clumps by mass. Step 705 may remove at least 50%, or at least about 60%, or at least about 70%, or at least about 80%, or at least about 90%, or at least about 95%, or at least about 99% of the nonmagnetized components by mass, such as tungsten-containing alloys, steel and other ferromagnetic iron alloys, from the mixed scrap.

[0180] The oversize fraction containing magnet-comprising clumps may have a purity of magnet content between about 1% and about 99%, or more particularly between about 5% and about 90%, or more particularly between about 10% and about 80% by mass. Stated differently, the oversize fraction containing magnet-comprising clumps may comprise less than about 99%, or less than about 80%, or less than about 40%, or less than about 30%, or less than about 20%, or less than about 1% by mass non-magnetized components, such as tungsten-containing alloys, steel and other ferromagnetic iron alloys.

[0181] The mid-size fraction may also comprise less than about 99%, or less than about 80%, or less than about 50%, or less than about 30%, or less than about 10%, or less than about 1% by mass magnetized components. The mid-size fraction may comprise at least about 1%, or at least about 30%, or at least about 60%, or at least about 80%, or at least about 90%, or at least about 99% by mass of the tungsten-containing alloys, steel and other ferromagnetic iron alloys in the mixed scrap.

[0182] The composition of the fine fraction dust may comprise greater than about 10%, greater than about 30%, greater than about 70%, greater than about 80%, greater than about 90%, greater than about 99% magnet components by mass, which may have been demagnetized in the milling process.

[0183] In a non-limiting embodiment, the first screen comprises a mesh with a 80% passing (P₈₀) size greater than about 0.5 inches, or more typically greater than about 1 inch, or more typically greater than about 2 inches. The first screen may comprise a P₈₀ size between about 0.5 to about 5 inches. The second screen comprises a mesh with P₈₀ size of less than about 2 inches, or more typically less than about 1 inch, or more typically less than about 0.5 inches.

[0184] The process 700 may further include an optional sixth step 706 to combine the fine fraction dust with dust from the dust collection system. As a seventh step 707, the process 700 then passes the combined dust stream through a scavenger circuit that may also include re-magnetizing, clumping, and screening steps, specifically calibrated for finer particle sizes, to collect remaining magnetic components from the dust.

[0185] As an optional eighth step 708, the magnet clumps from step 705 and step 707 may then be combined into a magnet pre-concentrate. Magnet pre-concentrate may refer to magnet clumps from step 705, from step 707, or the combination of the magnet clumps from step 705 and 707.

[0186] In an optional step, the magnetic pre-concentrate may be de-magnetized by methods disclosed herein, such as by heating, to deplete the magnetic field of the magnetic components in the clumps to about zero or a negligible value. In some embodiments, demagnetizing the pre-concentrate may serve to break up the clumps.

[0187] At step 709, the physical differences between the magnetic components of the present disclosure and the non-magnetic components within the clumps, such as tungsten-containing alloys, steel and other ferromagnetic iron alloys, may be utilized to further remove the non-magnet components to form a magnet concentrate. For example, step 709 may exploit the size reduction rate discrepancies between the magnetic components and the non-magnetic components. Specifically, the magnetic components are more brittle than the non-magnetic components, namely tungsten-containing alloys, steel and other ferromagnetic iron alloys, and as such, the magnetic components will have a faster size reduction rate.

[0188] Step 709 may include inputting the magnet pre-concentrate to a further size reduction apparatus, such as a rapid grind or mill apparatus (e.g., ball mill, rod mill, or a combination thereof), followed by screening. As the magnetic components have a faster rate of reduction, the magnetic components reduce in size and pass through one or more screens for collection more quickly than the non-magnet components. The non-magnet components will then collect on the surface of the one or more screens.

[0189] Screening may include passing the reduced components over one or more screens to separate the magnet components from the non-magnet components. As the magnetized components typically reduce in size more quickly than the non-magnet components, the magnetized components will pass though the one or more screens, and the non-magnet components will remain on the surface of the screens.

[0190] Step 709, produce a magnet concentrate of a purity of at least about 50%, or at least about 70%, or at least about 80%, or at least about 85%, or at least about 90%, or at least about 95%, or at least about 99% magnetic components by mass. Stated differently, the magnet concentrate may comprise less than about 50%, or less than about 30%, or less than about 15%, or less than about 10%, or less than about 5%, or less than about 1% nonmagnetized components by mass, such as tungsten-containing alloys, steel and other ferromagnetic iron alloys.

[0191] Additionally, or alternatively, a method may be used with or without the above mentioned includes refining, demagnetizes the agglomerations, and while the material is at temperature, the method separates the steel and other ferromagnetic iron alloys from the magnets using magnetic separation. Conducting magnetic separation at temperature exploits the differences in magnetic attraction of steel and other ferromagnetic iron alloys and magnets at high temperatures and can be used to concentrate the material.

[0192] As noted above, all or only a subset of the illustrated steps of process 700 may be undertaken.

[0193] One or more steps of the third embodiment may be combined with one or more of the first and second embodiments. For example, methods of the first embodiment (i.e., Figs. 2 to 4) may be employed to separate magnet clumps from non-magnetic materials. The methods of the first embodiment may be used in place of or in combination with step 705 of Fig. 7. It should be understood that magnetic clump separation (from non-magnetic material) may be performed manually (e.g., by-hand, via screening) or via autonomation (e.g., methods described with reference to Figs. 2 to 4).

[0194] Embodiment 4 - Paramagnetic upgrading of mixed oxides to produce a REE oxide concentrate

[0195] Iron oxide, some tungsten-containing materials, and rare earth element oxides (REE oxides) are paramagnetic, meaning they are weakly attracted to a magnetic field. It is possible to separate different paramagnetic materials from one other by exploiting their differing magnetic susceptibilities (Xm) using a very strong magnetic field. Table 1, below, lists a measure of magnetic susceptibilities of various materials.

[0196] Table 1. Measure of magnetic susceptibilities of various materials. Material Xm, 10-6cm3mol-1Remarks Iron metal Infinite Ferromagnetic Iron(II) oxide +7,200 Paramagnetic Neodymium metal +5,930 Paramagnetic Neodymium oxide +10,200 Paramagnetic Tungsten _+6.8 _ Paramagnetic

[0197]

[0198] Embodiment 5 - Mechanical sorting of magnets from mixed scrap using magnetic field detection

[0199] As is well known, while permanent magnets produce a magnetic field, tungsten-containing materials, steel and other ferromagnetic iron alloys, by itself, does not. In one embodiment, these properties are utilized as follows. An array of magnetic field sensors (e.g., magnometer or Gauss meter) is provided to build a topographic map of magnetic field strength of a mixed scrap on a moving conveyor. Signal processing is then employed to analyze images of the mixed scrap, and to infer locations of magnets within a mixed scrap containing magnetic components and steel and other ferromagnetic iron alloys fragments. A mechanical method such as an air jet may then be used to segregate the magnets based on the inferred locations.

[0200] One specific embodiment includes four parts for magnet sorting: stimulation, sensor, signal processing, and mechanical sorting. FIG. 8 depicts one specific embodiment. Mixed feed material 83 is moved in a thin layer along a conveyor belt 81 and images of the material are captured by a detector or a sensor 85 similar to digital camera, that is capable of capturing and representing the magnetic field within its field of view.

[0201] A computing device 86 executing a proprietary software algorithm is then used to processes the images to identify the location of the magnets. A mechanical device 87, which may be an air gun in this embodiment, is then employed to pick out the desired magnetic components. A subsystem comprising the sensor 85, computing device 86 including the software may be formed as a stand-alone system. The stand- alone subsystem above may be deployed exclusively for internal use as part of a conveyor, or alternately may be built as a separate equipment package suitable for use by scrapyards. This embodiment may require a detector having a sensor capable of representing magnetic fields. The associated signal processing may present difficulties, as the raw magnetic field map may appear to resemble undulating hills rather than clear peaks. Likewise, a wide distribution of small magnet particles or dust may generate a broad, weak signal that might be difficult to distinguish from background noise. Persons of skill in the art of magnetic fields expect that the signals obtained from such a setup would be very noisy. Further, ferrous material may be magnetically attracted to the magnets and remain stuck during said mechanical sorting, resulting in high contamination of the magnet concentrate.

[0202] FIG. 9 shows various physical elements of computer system 86 of FIG. 8. As shown, computer system 86 has a number of physical and logical components, including a processor 90, memory 92 which may be in the form of random access memory (" RAM"), an interface circuit 96, an input / output (" I / O") interface 94, a network interface 97, non-volatile storage 98. Interface circuit 96 enabling processor 90 to communicate with the other components. Processor 90 executes at least an operating system, and a proprietary software noted above for analyzing images of magnetic fields or related properties captured by sensor 85. Memory 92 provides relatively responsive volatile storage to processor 90. I / O interface 94 allows for input to be received from one or more devices, such as a keyboard, a mouse, etc., and outputs information to output devices, such as a display and / or speakers. Network interface 97 permits communication with other computing devices over computer networks such as Internet. Non-volatile storage 98 stores the operating system and programs, including computer-executable instructions for implementing the software. During operation of computer system 86, the operating system, the programs and the data may be retrieved from non-volatile storage 98 and placed in memory 92 to facilitate execution.

[0203] Any module, unit, component, server, computer, terminal, engine or device exemplified herein that executes instructions may include or otherwise have access to computer readable media such as storage media, computer storage media, or data storage devices (removable and / or non-removable) such as, for example, magnetic disks, optical disks, or tape. Computer storage media may include volatile and non-volatile, removable and non-removable media implemented in any method or technology for storage of information, such as computer readable instructions, data structures, program modules, or other data. Examples of computer storage media include RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by an application, module, or both. Any such computer storage media may be part of the device or accessible or connectable thereto. Further, unless the context clearly indicates otherwise, any processor or controller set out herein may be implemented as a singular processor or as a plurality of processors. The plurality of processors may be arrayed or distributed, and any processing function referred to herein may be carried out by one or by a plurality of processors, even though a single processor may be exemplified. Any method, application or module herein described may be implemented using computer readable / executable instructions that may be stored or otherwise held by such computer readable media and executed by the one or more processors.

[0204] Any of the first through fifth embodiments may be used in combination with one another to produce a target magnetic material, such as target magnetic material 24 described with reference to FIG. 1, and ferromagnetic material fraction 132 substantially free of magnetic material.

[0205] Overall mechanical process

[0206] In one embodiment, an overall process combines a series of individual physical processing steps in a unique combination that is able to output an enriched magnet concentrate from mixed scrap material.

[0207] The process 1200 is summarized in FIG. 11 and comprises the following steps: At step 1201, feed material comprising mixed scrap that contains some proportion of magnets is obtained. As described herein, the magnets may comprise rare earth elementcomprising magnets, such as but not limited to, neodymium magnets, samarium cobalt magnets, cobalt and / or nickel -comprising magnets such as, but not limited to aluminum nickel cobalt magnets, or any combination thereof. The feed material may further include non-REE-comprising magnets, and non-magnetic materials including non-magnetic and non-ferromagnetic metals such as certain tungsten-containing materials, aluminum, copper, and gold, ferromagnetic materials such as certain tungsten-containing materials, steel and other ferromagnetic alloys, and other non-ferromagnetic materials such as water, plastic, wood, rubber, etc.

[0208] The composition of the feed material may comprise between about 1% and about 90%, or more typically between about 2% and about 10%, or even more typically between about 3% and about 5% by mass rare-earth element comprising magnets. The composition of the feed material may comprise between about 10% to about 90%, or more typically between about 20% and 80%, or even more typically between about 30% and 70% by mass non-magnetic materials.

[0209] At step 1202, the size of the components of the mixed scrap is reduced through a milling process, such as a hammer mill, as described in step 701 of Embodiment 3. Components of the mixed scrap may be milled to achieve an average particle size ranging from about 5 inches and about 0.5 mm, or more particularly between about 4 inches and about 1 mm, or even more particularly between about 3 inches and about 1 cm.

[0210] Optionally, at step 1203 separation of the ferromagnetic (e.g., certain tungsten-containing materials, steel and other ferromagnetic iron alloys, magnets) and non-ferromagnetic materials (e.g., certain tungsten-containing materials, aluminum, copper, plastics, other metals) using magnetic separation is undertaken and further separation of the non-ferromagnetic fraction is achieved using one or more of eddy current separators, shaker tables, air tables, optical sorters, gravity sorters, etc., as described in more detail with reference to the first and / or second embodiments. Step 1203 may separate at least most (i.e., at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 99% by mass) of the non-ferromagnetic materials from the ferromagnetic materials. The separated non-ferromagnetic materials in the non- ferromagnetic material fraction may comprise less than about 40%, or more typically less than about 30%, or more typically less than about 25%, or more typically less than about 20%, or more typically less than about 15%, or more typically less than about 10%, or more typically less than about 5%, or more typically less than about 1% by mass ferromagnetic material. More specifically, the separated non-ferromagnetic material fraction may comprise less than about 40%, or more typically less than about 30%, or more typically less than about 25%, or more typically less than about 20%, or more typically less than about 15%, or more typically less than about 10%, or more typically less than about 5%, or more typically less than about 1% magnets by mass.

[0211] The separated ferromagnetic material fraction may comprise less than about 40%, or more typically less than about 30%, or more typically less than about 25%, or more typically less than about 20%, or more typically less than about 15%, or more typically less than about 10%, or more typically less than about 5%, or more typically less than about 1% non-ferromagnetic material by mass.

[0212] The composition of the separated ferromagnetic material fraction may comprise less than about 50%, or more typically less than about 40%, or more typically less than about 30%, or more typically less than about 25%, or more typically less than about 20%, or more typically less than about 15%, or more typically less than about 10%, or more typically less than about 5%, or more typically less than about 1% by mass non-rare earth comprising magnets (e.g., cobalt and / or nickel-comprising magnets such as, but not limited to aluminum nickel cobalt magnets), rare earth comprising magnets (e.g., samarium cobalt magnets, neodymium magnets), or both. Stated differently, the composition of the separated ferromagnetic material fraction may comprise at least about 50%, or more typically at least about 60%, or more typically at least about 70%, or more typically at least about 75%, or more typically at least about 80%, or more typically at least about 85%, or more typically at least about 90%, or more typically at least about 95%, or more typically at least about 99% by mass tungsten-containing material, steel and other ferromagnetic iron alloys.

[0213] At step 1204, the ferromagnetic material fraction is separated into a target magnetic materials-enriched "magnet concentrate” and a non-target magnetic materials- depleted fraction comprising tungsten-containing materials, steel, and other ferromagnetic iron alloys stream by one of the methods described above (e.g., size reduction and screening, demagnetization and re-magnetization, etc.) in the Figs. 1 to 12 and can used in any order. Step 1204 may separate at least most (i.e., at least about 20%, at least about 60%, at least about 85%, at least about 90%, at least about 95%, at least about 99% by mass) of the nontarget magnetic materials from the target magnetic materials. The separated non-target magnetic material fraction may comprise less than about 40%, or more typically less than about 30%, or more typically less than about 25%, or more typically less than about 20%, or more typically less than about 15%, or more typically less than about 10%, or more typically less than about 5%, or more typically less than about 1% by mass target magnetic materials.

[0214] The separated target magnetic material fraction may comprise less than about 60%, or more typically less than about 30%, or more typically less than about 25%, or more typically less than about 20%, or more typically less than about 15%, or more typically less than about 10%, or more typically less than about 5%, or more typically less than about 1% non-target magnetic materials by mass.

[0215] The composition of the separated target magnetic material fraction may comprise at least about 10 to 80%, or more typically 20 to 60% tungsten-containing materials, steel, and other ferromagnetic iron alloys by mass. Stated differently, the composition of the separated target magnetic material fraction may comprise at least about 5 to 80%, or more typically at least about 15 to 60%, or more typically at least about 25 to 50% by mass non-rare earth comprising magnets (e.g., cobalt and / or nickel-comprising magnets such as, but not limited to aluminum nickel cobalt magnets), rare earth comprising magnets (e.g., samarium cobalt magnets, neodymium magnets), or both.

[0216] The composition of the separated non-target magnetic material fraction may comprise tungsten-containing materials, steel and other ferromagnetic iron alloys, plastics, glass, aluminum, copper, gold, and other non-magnetic metal elements and compounds, wood, etc.

[0217] Step 1205 involves grinding target magnetic enriched material and screening to produce a magnet concentrate of high purity, as described in step 709 of the third embodiment.

[0218] Step 1205 may remove at least 50%, or at least about 60%, or at least about 70%, or at least about 80%, or at least about 90%, or at least about 95%, or at least about 99% by mass of the remaining non-magnetized components (e.g., tungsten-containing material, steel and other ferromagnetic iron alloys, plastics, glass, aluminum, copper, gold, and other non-magnetic metal elements and compounds, wood, etc.) from the target magnetic enriched material. The magnet concentrate may have a purity of at least about 30%, or at least about 50%, or at least about 80%, or at least about 90%, or at least about 95%, or at least about 99% by mass magnetic components (e.g., non-rare earth element magnets, rare earth element-comprising magnets). State differently, the magnet concentrate may comprise less than about 70%, or less than about 50%, or less than about 20%, or less than about 10%, or less than about 5%, or less than about 1% by mass non-magnetized components, such as steel and other ferromagnetic iron alloys.

[0219] The process 1200 then terminates.

[0220] Separation of Tungsten-Containing Materials from Other Non-Magnetic Materials Returning to Fig. 23, the non-ferromagnetic material fraction 2324 and ferromagnetic material fraction 2316 are supplied as separate feed streams to the separation of target material block 2340, which includes the physical processing unit 2344 and chemical processing unit 2352 to form purified non-ferromagnetic and ferromagnetic fractions 2360 and 2356 containing one or more target materials. In some embodiments, the non-ferromagnetic fraction 2360 comprises at least most and more typically at least about 75% of the tungsten-containing material with at least most and more typically at least about 75% of the magnets in the comminuted feed stream 2312 being in the ferromagnetic fraction 2356 or in the target magnetic materials 24. In such embodiments, most of the tungsten-containing material is present as a non-ferromagnetic material. In other embodiments, the ferromagnetic fraction 2356 comprises at least most and more typically at least about 75% of the tungsten-containing material and at least most and more typically at least about 75% of the magnets in the comminuted feed stream 2312. In such embodiments, most of the tungsten-containing material is present as a ferromagnetic material. As will be appreciated, tungsten can be part of ferroalloy e.g., Ferrotungsten (FeW) which is a metal alloy made of iron and tungsten. In some embodiments, the ferromagnetic fraction 2356 comprises at least most and more typically at least about 75% of the tungsten-containing material and the target magnetic materials 24 comprises at least most and more typically at least about 75% of the magnets in the comminuted feed stream 2312.

[0221] The different physical processing techniques to separate the ferromagnetic material into the purified ferromagnetic fraction 2356 and a separate target magnetic materials-enriched "magnet concentrate” or magnetic material-containing fraction are discussed above in connection with Figs. 1-5, 7-8, and 11. The physical processing unit 2344 can separate at least most of the tungsten-containing material from at least most of the other materials in the non-ferromagnetic material fraction 2324 by any suitable technique, such as particle size, gravity, magnetic properties, and the like. Regarding particle size separation, tungsten-containing materials, in some applications, will be more resistant to comminution than other non-ferromagnetic materials and consequently may have a larger particle size distribution than the other non-ferromagnetic materials. Different size fractions can be separated by screening or filtration, hydrocyclone(s), differential centrifugation and other field-flow fractionation techniques, gravity sedimentation, flotation, and other techniques known to those of skill in the art.

[0222] Gravity separation employs a higher density of tungsten-containing materials compared to other non-ferromagnetic materials. Separation based on gravity or specific gravity can be gravity separating techniques such as hydrocyclone(s), jigging gravity separation, air classification zig-zag air classifiers, and other classification techniques, shaker gravity separation, spiral chute gravity separation, dense medium separation, and fluid-based separating media (e.g., heavy medium beneficiation), jig beneficiation, shaking table beneficiation, chute beneficiation, centrifugal force beneficiation, air beneficiation, and other techniques.

[0223] Magnetic separation employs the different magnetic properties of tungsten-containing materials when compared to other non-ferromagnetic materials. When the tungsten-containing material has paramagnetic properties, magnetic separation techniques can be employed (as discussed above) in which one or more magnets having at least a minimum field strength of about 12-18 kG are used to alter a path of travel of the target materials from a conveyance device when compared to the non-target materials.

[0224] Exemplary magnetic separation devices include those described above and devices positioning one or more magnets inside separator drums.

[0225] The chemical processing unit 2352 can be used to separate ferromagnetic materials 2356 from other residual non-ferromagnetic materials or into its various valuable metal components (e.g., REEs, copper, iron, nickel, cobalt and / or boron) in the purified ferromagnetic fraction 2356 as described in Figs. 10, 13-14, and 17-18 below, or to separate tungsten-containing materials from other non-ferromagnetic materials in the tungsten-containing fraction 2360 as described below in connection with Figs. 25 and 27. The ferromagnetic fraction 2356 may contain tungsten in the form of a ferro alloy and can be separated using methods described below in connection with Figs. 25, 26 and 27.

[0226] Regardless of the technique employed, the tungsten in the tungsten-containing material is recovered typically as substantially pure tungsten, tungsten carbide, or as an alloyed element.

[0227] An alternative embodiment of the physical separation circuit is shown in Fig. 24. As discussed above, the end-of-life electronic devices are disassembled to provide a subassembly comprising one or more haptic feedback modules contained in the device. Disassembly can be done manually and / or robotically, depending on the application. The resulting subassembly typically includes magnetic material (including ferromagnetic material) and tungsten-containing material.

[0228] The subassemblies containing the haptic feedback modules are comminuted by a size reduction apparatus, such as by one or more shredders, crushers, or mills to form a comminuted feed stream having a desired particle size (step 2308).

[0229] Comminuted feed stream 2312 is fed directly into a physical processing unit 2406 that separates the comminuted feed stream into separate ferromagnetic and tungsten-containing fractions. The ferromagnetic fraction contains at least most and more typically at least about 75% of the magnets and ferromagnetic material in the comminuted feed stream (or is magnet rich) while the tungsten-containing fraction contains at least most and more typically at least about 75% of the tungsten in the comminuted feed stream (or is tungsten-rich).

[0230] Regarding particle size separation, tungsten-containing materials, in some applications, will be more resistant to comminution than ferromagnetic materials, such as rare earth and non-rare earth magnets, and consequently may have a larger particle size distribution than the other ferromagnetic and non-ferromagnetic materials. Different size fractions can be separated by screening or filtration, hydrocyclone(s), differential centrifugation and other field-flow fractionation techniques, gravity sedimentation, flotation, and other techniques known to those of skill in the art.

[0231] Gravity separation employs the higher density of tungsten-containing materials compared to other lower density non-ferromagnetic and ferromagnetic materials. Gravity separation based on gravity or specific gravity can be gravity separating techniques such as hydrocyclones(s), jigging gravity separation, air classification zig-zag air classifiers, and other classification techniques, shaker gravity separation, spiral chute gravity separation, dense medium separation, and fluid-based separating media (e.g., heavy medium beneficiation), jig beneficiation, shaking table beneficiation, chute beneficiation, centrifugal force beneficiation, air beneficiation, and other techniques.

[0232] Magnetic separation employs the different magnetic properties of tungsten-containing materials when compared to ferromagnetic materials. When the tungsten-containing material has paramagnetic properties, magnetic separation techniques can be employed in which one or more magnets having at least a minimum field strength (e.g., about 0.5 and more typically about 1 kG for ferromagnetic materials and about 12-18 kG for paramagnetic materials) are used to alter a path of travel of the target ferromagnetic materials when compared to the tungsten-containing materials. Exemplary magnetic separation devices include those described above and devices positioning one or more magnets inside separator drums. When the tungsten-containing materials are paramagnetic, the ferromagnetic material is separated from the paramagnetic material by using magnets of different field strengths, such that a first magnetic separation unit uses a magnetic field strength between about 0.5 to about 11 kG to separate ferromagnetic materials from paramagnetic and other nonferromagnetic materials while a second magnetic separation unit in the physical processing unit 144 uses a higher magnetic field strength of more than 11 kG and more typically of more than about 12 kG to separate the paramagnetic materials from other non-ferromagnetic and non-paramagnetic materials.

[0233] In another process, the ferromagnetic material is demagnetized as described above before being separated from the paramagnetic or non-ferromagnetic tungsten-containing material by any of the above techniques. A variation of this process is shown in Fig. 26 discussed below.

[0234] In step 2408, impurities in the separated ferromagnetic fraction (which is magnet rich) and the tungsten-containing fraction are removed to form purified ferromagnetic and tungsten-containing fractions. The impurities can take many forms, such as plastics, other base metals such as aluminum, copper, iron, and boron and base metal alloys (such as steel), and the like. Such impurity separation techniques can be any of those discussed above, including separation based on particle size, magnetic properties, gravity (e.g., density or specific gravity), and the like.

[0235] To prepare for downstream chemical processing steps, one or both of the separated and purified ferromagnetic and tungsten-containing fractions is ground separately for preparing more finely sized materials containing most of the rare earth and non-rare earth magnets and tungsten, respectively. Typically, the particles after grinding have a P₀ size ranging from about 10 to about 5000 microns and more typically from about 100 to about 2000 microns.

[0236] The ground ferromagnetic and tungsten-containing fractions are fed into the chemical processing unit 2352, which has different configurations for the different constituent-containing fractions. Exemplary configurations of the chemical processing unit 2352 for the ferromagnetic fraction are shown in Figs. 10, 13-14, and 17-18 or for the tungsten-containing fraction are shown in Figs. 25 and 27.

[0237] Referring to Fig. 26, another embodiment of the physical processing unit 2344 of the present disclosure is shown.

[0238] As discussed above, the end-of-life electronic device are disassembled in step 2304 to provide a subassembly comprising one or more haptic feedback modules contained in the device. Disassembly can be done manually and / or robotically, depending on the application. The resulting subassembly typically includes magnetic material (including ferromagnetic material) and tungsten-containing material.

[0239] The subassemblies containing the haptic feedback modules are comminuted by a size reduction apparatus, such as by one or more shredders, crushers, or mills to form a comminuted feed stream having a desired particle size (step 2308).

[0240] The comminuted feed stream 2312 is formed into a slurry typically having a solids content ranging from about 1 to about 50 vol.% and fed directly into a flotation circuit (step 2600) (which may or may not be aerated) to concentrate at least most of the metallic fractions (including tungsten and REEs) in an underflow fraction and remove hydrophobic and buoyant lightweight non-ferromagnetic materials, such as plastics, in an overflow fraction followed by screening to separate the solids in the underflow from the liquid phase. Typically, the flotation is substantially free of collectors and frothers.

[0241] In step 2608, the separated solids are demagnetized as discussed above to form a demagnetized metallic fraction containing at least most and more typically at least about 75% of the REEs, tungsten and other base metals in the comminuted feed stream 2312. Alternatively, the separated solids may be further comminuted to substantially demagnetize the metallic fraction.

[0242] In step 2616, the tungsten-containing materials are separated from the REEs and other metals using gravity separation techniques as discussed above to form a tungsten-containing fraction 2620 comprising at least most and more typically at least about 75% of the tungsten in the comminuted feed stream 2312 and a metal fraction comprising at least most and more typically at least about 75% of the other base metals and REEs in the comminuted feed stream 2312.

[0243] Chemical system / processes

[0244] Some embodiments of the system disclosed herein, although characterized as chemical processes, may contain steps or processes that also exploit physical properties of the material components. A description of each of the process constituents is provided below, although the order and use of the process constituents may change.

[0245] Certain specific terms for steps or processes used throughout the present description may be read and understood as follows, unless the context indicates otherwise.

[0246] Grinding:

[0247] To facilitate reaction kinetics, magnet material (e.g., magnet concentrate from Step 1205 of Fig. 11) is comminuted and screened to ensure a target particle size, such as 80% passing (or P₀ size) between about 1 to about 5000 microns, or more typically between about 5 to about 1000, or more typically between about 10 to about 500 microns, or more typically between about 50 to about 250 microns, or more typically about 100 microns. Comminution may be performed by a hammer mill, ball mill, rod mill, etc.

[0248] Comminution typically generates heat and for some materials, such as neodymium magnets or other metals, the attendant dust particles produced may be flammable and / or explosive. To eliminate or at least reduce this risk several methods may be used including but are not limited to the addition of water, cutting fluids, dry ice, nitrogen gas, argon, and carbon dioxide or a combination thereof. The use of water and dry ice may act to reduce the heat below the temperature of combustion, and the use of the gases may act to limit the availability of oxygen, while the use of dry ice may act to reduce heat and limit the availability of oxygen. In some embodiments, the dust may be collected for further processing / recycling.

[0249] Washing:

[0250] A valuable feed source for magnet recycling includes swarf, which is a manufacturing waste product. Swarf is typically mixed with a liquid used as a cutting or cooling aid, such as a cutting oil. Swarf may be washed using, water, heated water, surfactants, such as but not limited to sodium dodecyl sulfate, Alconox®, Alcojet®, Detergent 8, and Detonox®, and / or other reagents including but not limited to: dichloromethane, that breakdown organic material. Washing procedures have been tested and efficacies range from removing about 70% to about 100% of the entrained cutting liquid.

[0251] Washing may remove at least most (i.e., at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 99% by mass) of the oil from the swarf.

[0252] Specifically, magnet manufacturing swarf involves metal pieces soaked in oil and water. This is then cleaned before it can be fed to the process of FIG. 1.

[0253] In the embodiment depicted in FIG. 12, during the cleaning process, a volatile solvent or water (individually and collectively referred to as "solvent") is mixed with the swarf to dissolve and / or separate all oil. The swarf is then separated from the solvent by settling and decantation, followed by a final wash with more solvent.

[0254] The oil-loaded solvent is then distilled to recover and recycle the solvent, and the residual oil is sold or disposed.

[0255] Non-limiting examples of a volatile solvent includes trichloroethylene and d-Limonene and other surfactants, such as but not limited to sodium dodecylsulfate, Alconox®, Alcojet®, Detergent 8, and Detonox®, and / or other reagents including but not limited to: dichloromethane, that breakdown organic material.

[0256] Fig. 12 depicts a non-limiting example of washing, according to embodiments disclosed herein.

[0257] Roasting:

[0258] To facilitate the removal of impurities, the magnet material may be roasted at a temperature that varies between about 150 °C and about 1000 °C, or more typically between about 200°C and about 900°C, or more typically between about 300°C and about 800°C, or even more typically between about 400°C and about 700°C to alter the oxidative state of one or more impurities in the magnet material. Specifically, oxidative roasting converts at least a portion of the impurities to oxides. Roasting, according to embodiments of the present disclosure, may achieve 100% oxidation of the magnet material. Other chemicals, such as but not limited to lime could be added to adsorption any harmful chemicals during this process. The magnet material may be roasted between about 30 minutes to about 6 hours, or more typically between about 45 minutes to about 3 hours, or more typically between about 1 hour to about 2 hours. It is noted that roasting may occur over any amount of time to achieve a desired oxidation level of the input magnet material. In embodiments, roasting may be performed with an air flow about 1 to 8.5 liters per minute (LPM). Oxidation roasting equipment may include a rotary kiln, a multichamber baking furnace, fluidized baking furnace, and the like.

[0259] Leaching:

[0260] The leaching process utilizes a lixiviant, which may include but is not limited to: hydrochloric acid, sulphuric acid, nitric acid, formic acid, citric acid, and / or other organic acids or a combination thereof. The lixiviant may be selected based at least in part on the composition of the magnet material in the swarf and / or magnet concentrate produced above with reference to the mechanical process. As will be appreciated, tungsten is not soluble in most acids, but it can be readily soluble in a mixture of nitric acid and hydrofluoric acid. Its solubility in nitric or sulfuric acid can be increased at higher temperatures and / or by addition of a tungsten solubilizing agent (e.g., a complexing agent and / or oxidizing agent (or oxidant)). Tungsten is substantially insoluble in mineral acids like hydrochloric acid at room temperature.

[0261] In embodiments, the pulp density (i.e., the solid mass to liquid mass ratio) of the magnet material to lixiviant ranges from about 1% to about 30%, or more typically from about 3% to about 25%, or even more typically from about 5% to about 20%, where the percents are given as a solid mass to total solid plus liquid mass percentages.

[0262] In embodiments, the pH of the lixiviant may be less than about pH 5, or more typically less than about pH 4, or more typically less than about pH 3. The pH of the lixiviant may range from about pH 0 to about pH 2.5.

[0263] The magnet material may be contacted with the lixiviant and allowed to react for about 1 to about 8 hours, and more typically from about 2 to about 7 hours, or even more typically for about 3 to about 6 hours.

[0264] The temperature of the leach process may range from about 10 to about 110°C, and more typically from about 50 to about 100°C, and more typically from about 60 to about 90°C.

[0265] To date, leaching tests have demonstrated extraction efficiencies of up to about 90%, or more typically up to about 95%, or more typically up to about 99%, or more typically up to about 100% by mass of the contained critical minerals, that includes rare earth elements, cobalt, and nickel, by controlling temperature, reaction time, and using an oxidizing agent. Control of some or all of these operating parameters may be used or not used.

[0266] While tungsten will normally remain substantially insoluble during acid leaching, a tungsten solubilizing agent (e.g., a complexing and / or oxidizing agent, such as phosphoric acid, hydrogen peroxide, or oxalic acid) may be added to the leaching solution to convert at least most of the otherwise insoluble tungsten into soluble tungsten complexes. In that event, the pregnant leach solution can contain substantial amounts of dissolved tungsten complexes.

[0267] The resulting pregnant leach solution composition may vary depending on the type of feed material. In a particular example, the solution may comprise between about 0.1 g / L and the solubility limit of the REEs in the pregnant leach solution. In embodiments, the solution may comprise between about 20 g / L REEs, between about 1 g / L and about 100 g / L iron, between about 0.1 g / L and about 2 g / L boron, between about 0. Ig / L and about 15 g / L cobalt, between about 0.01 g / L and about 5 g / L nickel, between about 0 g / L and about 10 g / L tungsten, and about 0.1 g / L and about 2 g / L other impurities (e.g., aluminum, zinc, copper).

[0268] Iron Removal:

[0269] Iron and other impurities may be precipitated from the process solution by adjusting the solution pH with calcium oxide, calcium hydroxide, calcium carbonate, magnesium oxide, magnesium hydroxide, magnesium carbonate, sodium hydroxide, or other alkaline reagents or minerals, or a combination thereof in an oxidative environment (i.e., in the presence of oxygen) achieved by the use of air, oxygen gas, or hydrogen peroxide, mixture of sulfur dioxide with oxygen or air gasses, permanganate, or other known oxidants in the industry or a combination thereof. The addition of copper ions and the use of solvent extraction may also be applied.

[0270] Specifically, iron can be removed by solvent extraction and precipitation as goethite or hematite.

[0271] In embodiments, the process solution may comprise an initial iron concentration ranging from about 1 g / L to about 100 g / L, and more typically from about 5 g / L to about 90 g / L, and more typically from about 10 g / L to about 75 g / L, and more typically from about 15 g / L to about 50 g / L.

[0272] The process solution may be adjusted to a pH less than about pH 6, and more typically less than about pH 5.5, and more typically less about pH 5.0, and even more typically less than about pH 4.5. The process solution may be adjusted to a pH between about pH 1.5 and pH 4.5, and more typically from about pH 1.5 to about pH 4.0, and even more typically from about pH 1.5 to about pH 3.5.

[0273] In embodiments, about a 50 wt.% hydrogen peroxide solution is added to the process solution to achieve a concentration in solution ranging from about 2% to about 40%, or more typically from about 5% to about 35%, or more typically from about 10% to about 30% by mass.

[0274] The type and amount of alkaline reagent added to the process solution may be based on pH of the alkaline reagent, current pH of the process solution, and desired pH of the process solution to precipitate at least a portion of the iron in solution.

[0275] In embodiments, a copper comprising solution, such as copper sulphate, may be added to the process solution in an amount ranging from about 20 g / L to about 150 g / L, and more typically from about 25 g / L to about 125 g / L, and even more typically from about 30 g / L to about 100 g / L.

[0276] The temperature of the iron removal process may range from about 10 to about 110°C, and more typically from about 50 to about 100°C, and more typically from about 60 to about 90°C.

[0277] The iron removal process may have a reaction time ranging from about 1 hour to about 15 hours, and more typically from about 2 to about 12 hours, and even more typically from about 3 to about 10 hours.

[0278] To date, test work has achieved removal of up to about 90%, or more typically up to about 95%, or more typically up to about 99%, or even more typically up to about 99.99% by mass iron from solution. In embodiments, one or more other impurities may precipitate out of solution with the iron, including aluminum, copper, zinc, or a combination thereof.

[0279] In the iron removal process of the present disclosure results in less than about 15%, or more typically less than about 10%, or more typically less than about 9%, or more typically less than about 8%, or even more typically less about 5% by mass loss of trace rare earth elements. That is, less than about 5% by mass of rare earth elements present in solution precipitate out of solution with the iron.

[0280] Following iron precipitation, the process solution may comprise less about 10%, or more typically less than about 5%, or more typically less than about 1%, or more typically less about 0.5% by mass iron and, in some embodiments, other impurities such as aluminum, copper, zinc, or a combination thereof. In embodiments, the process solution may be substantially free of iron and, in some embodiments, other impurities such as aluminum, copper, zinc, or a combination thereof.

[0281] Iron removal targets iron precipitation while non-iron metals remain in solution, particularly boron, cobalt, and nickel. In embodiments, less than 25%, or more particularly less than 20%, or more particularly less than 15%, or more particularly less than 10%, or more particularly less than 5%, or more particularly less than 1% by mass of the boron, cobalt, and nickel present in the pregnant leach solution precipitate out during iron removal.

[0282] The resulting process solution following iron removal may comprise between about 0.1 g / L and the solubility limit of the REEs in the resulting process solution. In embodiments, the solution may comprise between about 50 g / L REEs, between about 0.001 g / L and about 5 g / L iron, between about 0.1 g / L and about 2 g / L boron, between about 0.1 g / L and about 14 g / L cobalt, between about 0.01 g / L and about 5 g / L nickel, between about 0.1 g / L and about 10 g / L tungsten, and about 0.1 g / L and about 2 g / L other impurities (e.g., aluminum, zinc, copper) based at least in part on the composition of the swarf and / or magnet concentrate produced above.

[0283] Oxalate Precipitation:

[0284] The production of a rare earth element (REE) material may be achieved by precipitation as a salt, such as an oxalate or a carbonate. Oxalate precipitation may occur after the precipitation of one or more impurities, such as iron, aluminum, copper, zinc, or a combination thereof. Such a precipitation may target a high purity REE-comprising product by dosing the solution with about 50% to 500%, or more typically with about 55% to about 250%, and even more typically with about 60% to about 200% the stoichiometric addition of the precipitating reagent relative to the target precipitant (e.g., REEs).

[0285] Oxalate precipitation may occur at a pH ranging from about pH 0.5 to about pH 5.5, and more typically from about pH 1.0 to about pH 5.0.

[0286] Oxalate precipitation may occur at a temperature up to about 100°C, or more typically up to about 90°C, or more typically up to about 80°C, or more typically up to about 70°C, or more typically up to about 60°C, or even more typically up to about 50°C.

[0287] The oxalate precipitation reaction may occur over 5 minutes to about 2 hours. To date, laboratory work has achieved between about 50% and about 100% recovery of REEs from the process solution. That is, following oxalate precipitation, the process solution may comprise about 50% to about 0% REE.

[0288] The REE oxalate precipitant comprises a purity of at least about 90%, or more typically at least about 95%, or more typically at least about 99%, or even more typically at least about 99.5% by mass REEs. That is, the REE precipitant comprises less about 10%, or more typically less about 5%, or more typically less about 1%, or even more typically less about 0.5% by mass non-rare earth elements and compounds.

[0289] In one embodiment, a process for selective precipitation of rare earth oxalates from iron-rich leach solutions involves controlling oxalate and / or oxalic acid addition to the process solution. When magnet-comprising material is leached in acid, the resulting pregnant leach solution may comprise many metals, including REEs, iron, aluminum, copper, nickel, tungsten, and others. The separation of these metals from one another, and particularly the separation of the REEs from non-REE metals, is desirable to ensure the quality of the REE product meets predefined specifications for their intended application.

[0290] One method of rare earth separation is selective REE oxalate precipitation. With this process other metals also precipitate as oxalates, requiring the resultant contaminated product to be further refined.

[0291] In the course of experimental work, it was observed that REE oxalates tend to precipitate first, followed by iron and other metal oxalates. In one embodiment of a process utilizing this observation, iron and other metals may be rejected by carefully controlling the stoichiometric amount of oxalate and / or oxalic acid that is added to the leach solution to nearly match, or be slightly above, relative to the amount of REEs. The embodiment involves pairing the monitoring of REE concentration in the leach solution with (near) exact dosing of oxalate and / or oxalic acid, such that REE precipitation is increased / maximized and iron precipitation is reduced / minimized. That is, the selective precipitation of rare earth oxalates comprises adding a stoichiometric amount of oxalate or oxalic acid such that as much REEs are precipitated as possible before iron and other impurities (e.g., aluminum, zinc, copper) begin precipitating out of solution. Such selective precipitation may leave some REEs in the process solution but the resulting REE oxalate precipitant will be highly pure.

[0292] In embodiments, selective REE oxalate precipitation converts at least most (i.e., at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 99%, at least about 99.5% by mass) of the REEs from the process solution to REE oxalates which precipitate out of the process solution. That is, less than about 25%, or about 20%, or about 15%, or about 10%, or about 5%, or about 1%, or about 0.5% by mass of the REEs may remain in the process solution following the selective REE oxalate precipitation.

[0293] The composition of the resulting oxalate precipitant may comprise at least about 75%, or more typically at least about 80%, or more typically at least about 85%, or more typically at least about 90%, or more typically at least about 95%, or more typically at least about 95.5%, or more typically about 100% by mass REE oxalates. That is, the resulting oxalate precipitant may comprise less than about 25%, or more typically less than about 20%, or more typically less than about 15%, or more typically less than about 10%, or more typically less than about 5%, or more typically less than about 1%, or more typically less than about 0.5%, or even more typically about 0% by mass non-REE oxalates or compounds (e.g., aluminum, iron, copper, zinc, cobalt, boron, nickel, tungsten, etc.).

[0294] In other embodiments, the stoichiometric amount of oxalate or oxalic acid added to the process solution may be selected to recover substantially all (i.e., at least about 90%, at least about 95%, at least about 99%, at least about 99.5%, at least about 99.9% by mass) of the REEs from the product solution. That is, less than about 10%, or about 5%, or about 1%, or about 0.5%, or about 0.1% by mass of the REEs may remain in the process solution following the oxalate precipitation.

[0295] In such embodiments, however, the resulting oxalate precipitate may comprise one or more non-REE impurities such as iron, aluminum, zinc, copper, tungsten, etc., oxalates, or combinations thereof. The resulting oxalate precipitant may comprise less than about 50%, or more typically less than about 40%, or more typically less than about 30%, or more typically less than about 25%, or more typically less than about 20%, or more typically less than about 15%, or more typically less than about 10%, or more typically less than about 5% by mass non-REE oxalates or compounds (e.g., aluminum, iron, copper, zinc, cobalt, boron, nickel, tungsten, etc.).

[0296] Calcination:

[0297] The conversion of oxalate and / or carbonates in the oxalate precipitant to an oxide is achieved by calcination. Calcination is the thermal treatment of a solid chemical compound whereby the compound is raised to high temperature without melting under restricted supply of ambient oxygen, to remove impurities or volatile substances. Specifically, the oxalate precipitate may be subjected to calcination for impurity removal, such as but not limited to nickel, cobalt, and iron oxalates, to recover recycled mixed rare earth oxide (rMREO).

[0298] The calcination may be carried out at a temperature of about 150 °C to about 1200 °C, in presence of air, with a reaction time ranging from 30 minutes to 8 hours.

[0299] This process may include selective calcination by targeting temperatures associated with the conversion of specific species, such as impurities..

[0300] In an embodiment, selective calcining of a mixed oxalate precipitate is followed by steps for separating impurities. As described above, REEs can be recovered from a leach solution by oxalate precipitation. This mixed oxalate precipitation process, even if tightly controlled, may produce a product that contains some impurities (e.g., iron, aluminum, zinc, copper, boron, cobalt, nickel, and / or tungsten). The conventional approach to purify the oxalate is to calcine substantially all of the components of the mixed oxalate to oxides and re-leach the mixed oxide, followed by hydrometallurgical purification.

[0301] Selective calcination of a mixed oxalate is an alternative that eliminates the need for re-leaching that may achieve the same result at lower cost. Nickel, cobalt, tungsten, and iron oxalates thermally decompose at a lower temperature than rare earth oxalates. As such, selective calcination may include calcining the mixed oxalate at a low temperature range to first convert the non-REE impurities to an oxide while the REE oxalates remain as oxalates. The low temperature range may include temperatures less than about 650°C, such that the first temperature range may comprise about 150°C to about 650°C. In some embodiments, the calcination process may include incrementally increasing the temperature within the low temperature range to selectively convert oxalates within the impurities to oxides. In a nonlimiting example, calcination may occur at a first low temperature range from about 150 °C to about 300 °C for a duration ranging from about 30 minutes to about 8 hours to convert a first oxalate impurity, then the temperature may be increased to a second low temperature range from about 300 °C to about 500 °C for a duration ranging from about 30 minutes to about 8 hours to convert a second oxalate impurity, then the temperature may be increased to a third low temperature range from about 500 °C to about 650 °C for a duration ranging from about 30 minutes to about 8 hours to convert a third oxalate impurity. It should be understood that this example is provided for understanding and the present disclosure is not so limited. The step-wise increase of temperature during calcination may include any number of increases in temperature ranges, over any time duration, etc.

[0302] Following calcination within the low temperature range, the calcination process may then include increasing the temperature to within a high temperature range from about 30 minutes to about 8 hours to convert the REE oxalates to REE oxides. The high temperature range may include about 650°C to about 1200°C. Calcination of the REE oxalates may similarly include step-wise increases in temperature as described with reference to the impurity calcination.

[0303] In embodiments, the differing properties (e.g., solubility, calcination, magnetism) of the REE oxalates or carbonates and / or REE oxides versus impurity oxides can then be exploited to purify the product. Purification may occur prior to calcination of the REE oxalates or after.

[0304] There are several variations of this embodiment. In one variation, a mixed oxalate precipitate comprising REEs and metal impurities is calcined between 150 and 1200°C. The resulting calcined product is then purified by leaching, washing, magnetic separation, or slag refining. The calcined product is leached in weak acid to remove the impurities, leaving behind REE oxalate. FIG. 10 depicts schematic block diagrams illustrating the above variations.

[0305] In embodiments, methods of the present disclosure may include performing non-selective calcination such that the temperature of the calcination is raised with a range from about 700°C to about 1200°C.

[0306] In embodiments, a calcination process may be strategically selected based at least in part on the oxalate precipitation process, or vice versa. For example, when selective precipitation is performed, the oxalate precipitant may comprise highly pure REE oxalates. Therefore, the process does not have to rely on calcination to purify the product. As such, non-selective calcination may be performed following selective oxalate precipitation to convert the REE oxalates to REE oxides. In another example, when non-selective oxalate precipitation is performed, the oxalate precipitant may comprise greater amount of impurities than is desired (e.g., greater than 20%, 15%, 10%, 5%, 1%, 0.5% by mass). Therefore, the process may rely on selective calcination to purify the REE product. As such, selective calcination may be performed following non-selective oxalate precipitation to convert at least most of the metal impurities (e.g., iron, aluminum, zinc, copper, boron, cobalt, nickel, and / or tungsten) and REE oxalates to oxides for purification. The resulting REE oxide may comprise at least about 80%, or more typically at least about 85%, or more typically at least about 90%, or more typically at least about 95%, or more typically at least about 99%, or more typically at least about 99.5%, or more typically at least about 99.5% REE oxides by mass. That is, the resulting REE oxides may comprise less than about 20%, or more typically less than about 15%, or more typically less than about 10%, or more typically less than about 5%, or more typically less than about 1%, or more typically less than about 0.5%, or more typically less than about 0.1% by mass non-REE impurities such as aluminum, zinc, copper, boron, nickel, cobalt, tungsten, etc.

[0307] Other REE recovery techniques may be employed than those expressly disclosed herein, such as solvent extraction.

[0308] Impurity Removal:

[0309] Trace level of impurities can have an adverse impact on the usability and value of high purity REE products. Removal of aluminum, copper, zinc, tungsten, and other impurities from the REE product solution may be accomplished using precipitation with calcium oxide, calcium hydroxide, magnesium oxide, magnesium hydroxide, sodium hydroxide, or other alkaline reagents, or a combination thereof. Solvent extraction and ion exchange may also be used to remove trace impurities.

[0310] When soluble tungsten complexes are present in the solution along with other dissolved metals, at least most of the tungsten, being amphoteric, can be selectively precipitated at a pH of less than about pH 7 while maintaining at least most of the other metals dissolved in solution; can be maintained in solution while at least most of the other dissolved metals are precipitated at a pH or more than about pH 7 using a precipitant, such as magnesium; and / or can be precipitated along with at least most of the other metals followed by a sulfuric acid leach to selectively dissolve at least most of the precipitated metals while leaving at least most of the tungsten in the solid phase. Tungsten can be precipitated from solution by contacting the solution with calcium at a pH ranging from about pH 9 to about pH 10 to precipitate at least most tungsten as calcium tungstate. Alternatively, tungsten may be recovered from solution as ammonium paratungstate (APT) at a pH ranging from about pH 7.5 to about pH 8.5 by contacting an ammonium compound with the solution. The precipitating reagent may be added to the process solution in amount ranging from about 50% to about 200% based on the stoichiometric amount of the tungsten in solution. Alternatively, dissolved tungsten may be selectively adsorbed on a solvent extraction or ion exchange resin that has a greater preference for tungsten over other dissolved metals. A TEVA resin is an example of such a resin.

[0311] Precipitation, solvent extraction, and / or ion exchange may remove at least most (i.e., about 75%, 80%, 85%, 90%, 95%, 99%, 99.5% by mass) of the remaining metal impurities from the process solution such that the process solution is substantially free (i.e., comprises less about 25%, less than about 20%, less than about 15%, less than about 10%, less than about 5%, less than about 1%, less than about 0.5% by mass) of iron, aluminum, copper, tungsten, and zinc.

[0312] Cobalt and / or Nickel Removal:

[0313] Magnets may comprise cobalt and / or nickel which are valuable critical metals and can be separated from the process solution using solvent extraction and / or precipitation as a hydroxide using a reagent such as, but not limited to, lime or sodium hydroxide, magnesium oxide, calcium oxide, magnesium hydroxide, and calcium hydroxide producing a mixed cobalt-nickel hydroxide product. Nickel and cobalt may be removed separately or simultaneously from the process solution based on the removal method. Nickel and / or cobalt removal may take place after rare earth element precipitation and secondary iron removal occurs. In embodiments, nickel and / or cobalt removal may occur at a pH ranging from about pH 5.5 to about pH 10.

[0314] The precipitating reagent may be added to the process solution in amount ranging from about 50% to about 200% based on the stoichiometric amount of the nickel and / or cobalt in solution.

[0315] In embodiments, nickel and / or cobalt removal may occur at a temperature ranging from about 25°C to about 90°C, with a reaction time ranging from about 30 minutes to about 6 hours.

[0316] The nickel and cobalt precipitation may recover at least most (i.e., at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 99%, at least about 99.5% by mass) of the nickel and / or cobalt from the process solution. That is, less than about 25%, or about 20%, or about 15%, or about 10%, or about 5%, or about 1%, or about 0.5% by mass of nickel and / or cobalt may remain in the process solution following nickel and cobalt precipitation.

[0317] As a result of the precipitation, a mixed hydroxide precipitate (MHP) may form comprising nickel and / or cobalt. The MHP may have comprise less than about 25%, or more typically less than about 20%, or more typically less than about 15%, or more typically less than about 10%, or more typically less than about 5%, or more typically less than about 1%, or more typically less than about 0.5% by mass impurities (e.g., non-nickel or cobalt elements / compounds).

[0318] Boron Removal:

[0319] Boron may be recovered from the process solution using ion exchange or solvent extraction to produce products such as, but not limited to, zinc borate, boric acid, and / or sodium borate.

[0320] In embodiments, boron removal may occur before or after nickel and / or cobalt removal and may be based on the pH of the ion exchange resin, pH of the process solution, amount of boron in solution, amount of nickel and / or cobalt in solution, selected precipitating agents, etc., or a combination thereof.

[0321] In a non-limiting example of ion exchange to remove boron, a boron-containing aqueous process solution with a pH of about pH 6 to about pH 11 is treated with a boronselective ion exchange resin, and boron is adsorbed onto the resin. The boron-selective ion exchange resin may be selected from a group of commercially available resins including but not limited to Amberlite PWA10, Ambersep IRA743, Purolite S108, Bestion BD501 and Mitsubishi Diaion CRB05. The boron can be eluted from the boron-loaded resin with one or more of hydrochloric acid, nitric acid, sulphuric acid, formic acid, citric acid, or a combination thereof.

[0322] The boron removal may recover at least most (i.e., at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 99%, at least about 99.5% by mass) of the boron from the process solution. That is, less than about 25%, or about 20%, or about 15%, or about 10%, or about 5%, or about 1%, or about 0.5% of boron by mass may remain in the process solution following the boron removal process.

[0323] As a result of the boron removal, a boron product may comprise less than about 25%, or more typically less than about 20%, or more typically less than about 15%, or more typically less than about 10%, or more typically less than about 5%, or more typically less than about 1%, or more typically less than about 0.5% by mass impurities (e.g., non-boron elements / compounds).

[0324] Overall chemical process:

[0325] An overall chemical process may combine a series of the above chemical processing steps to convert a variety of magnet-comprising feeds into a rare earth concentrate as well as optional secondary concentrates of iron, nickel, cobalt, boron, tungsten, or other elements. An exemplary process 1300 is summarized in FIG. 13.

[0326] Optionally, a first step (not depicted) may include washing of the feed using water, surfactant, solvent, or a combination thereof, as described in more detail above. Washing may be performed based on whether the mixed feed comprises oil or residue. Additionally or alternatively, process 1300 may include roasting of the (washed) feed at a temperature of 600 °C to 1000 °C, as described in more detail above, based on the feed material. Roasting may be performed to improve leaching recovery based on the composition of the feed material.

[0327] Step 1301 involves acid leaching of the mixed feed material as noted above, with one or more of hydrochloric acid, nitric acid, sulphuric acid, formic acid, citric acid or a combination thereof. Tungsten typically remains inert or forms insoluble tungstic acid and will be substantially insoluble in the leaching solution.

[0328] Step 1302 involves iron removal by pH adjustment and precipitation as discussed above.

[0329] Step 1303 involves rare earth recovery by precipitation as an oxalate as discussed above wither reference to oxalate precipitation.

[0330] Step 1304 involves calcining of the rare earth-comprising oxalate to rare earth oxide by a means described above.

[0331] Step 1305 involves impurity removal (i.e., removal of copper, aluminum, iron, tungsten, and other trace impurities) from the process solution by precipitation as a hydroxide, as described in more detail above.

[0332] Step 1306 includes boron recovery from the process solution by solvent extraction or ion exchange, as described in more detail above.

[0333] Step 1307 involves nickel / cobalt recovery from the process solution by pH adjustment and precipitation as a hydroxide, as described in more detail above.

[0334] Step 1308 involves treatment of process water for reuse, such as by addition of lime and / or carbon dioxide. The process 1300 then terminates.

[0335] A variation of process 1300 is shown as process 1400 depicted in FIG. 14 containing additional steps not present in FIG. 13.

[0336] Step 1401 involves washing of the feed (e.g., swarf and / or magnet concentrate) using water, surfactant, solvent, or a combination thereof, as described in more detail above.

[0337] Step 1402 involves roasting of the washed feed at a temperature of 600°C to 1000°C, as described in more detail above. Step 1403 involves acid leaching of the mixed feed material with one or more of hydrochloric acid, nitric acid, sulphuric acid, formic acid, citric acid or a combination thereof to form a pregnant leach solution, as described in more detail above. Tungsten oxide, when leached, typically remains inert or forms insoluble tungstic acid and will be substantially insoluble in the leaching solution.

[0338] Step 1404 involves purification of the pregnant leach solution by precipitation. Step 1404 may include removing a first amount of iron from the pregnant leach solution. If in step 1404, the iron is precipitated out of solution too aggressively (e.g., to remove substantially all or most of the iron), then REEs will also start precipitating out, resulting in REE losses. Therefore, there is a balance between removing most of the iron while and minimizing REE losses.

[0339] Step 1405 involves rare earth removal by precipitation as an oxalate, as described in more detail above.

[0340] Step 1406 involves calcining of the rare earth oxalate to rare earth oxide, with purification of the oxalate by a means described above.

[0341] Step 1407 involves impurities removal (e.g., iron removal) from the process solution by pH adjustment and precipitation. Step 1407 may target removal of the remaining iron in the solution to produce high purity biproducts, such as a nickel and / or cobalt product and a boron product.

[0342] Step 1408 involves nickel and / or cobalt removal by pH adjustment and precipitation as a hydroxide, as described in more detail above.

[0343] Step 1409 involves impurity removal by precipitation. Impurity removal may target trace amounts of copper and zinc. In some embodiments, the precipitation includes addition of sulfuric acid to form a sulfide precipitate. In some embodiments, the precipitation includes addition of sulfide such as sodium sulfide and hydrogen sulfide. Step 1409 is optional and may or may not be used based on the composition of the solution, the desired purity levels, etc.

[0344] Step 1410 involves boron removal by solvent extraction or ion exchange, as described in more detail above.

[0345] In embodiments, any water produced by the process disclosed herein may be subjected to further purification steps to remove contaminants from the water so the water can be re-used or disposed of.

[0346] Optionally, process water may then be treated for reuse, such as by addition of lime and / or carbon dioxide.

[0347] The process 1400 then terminates.

[0348] Other exemplary processes, according to embodiments of the present disclosure, are depicted in Figs. 15 to 17.

[0349] With reference to Fig.15, various end of life devices and other magnetic-containing waste are depicted including: rotors and stators harvested from electric car motors and other large permanent magnet (“PM“) motors, large alternators and large motor starters, small alternators, small motor starters, and small motors, all of which are forwarded to primary milling (Fig. 16); small power tools and audio speakers (from which the housing is removed before recycle), whole hard drives, meatballs, and hard drive corners, all of which are forwarded to secondary milling (Fig. 16); wet swarf, which is forwarded to decanting, washing and dewatering (Fig. 17); dry swarf, which is combined with the decanted, washed and filtered (and dewatered) wet swarf and the combined swarf is forwarded to fine milling (Fig. 17); and magnet manufacturing rejects and whole magnets (e.g., from MRI machines and wind turbines), which is optionally demagnetized and forwarded to shredding (Fig. 17).

[0350] Referring to Fig. 16, the tender spoke feed and tenacious spoke feed (which refers to the description of different magnet containing materials as shown in Fig. 15) is subjected to primary milling and / or secondary milling as shown to form a milled material, which is subjected to primary magnetic separation (discussed above), with the nonferrous byproduct being passed through a non-ferrous sorting operation (comprising a shredder and the metal separation unit operations of eddy current separation, color sorting, air table sorting, and strong magnet sorting to provide copper scrap, aluminum scrap, plastic scrap, and nonferrous steel and a ferrous reject material). The ferrous reject material is combined with the ferrous material from primary magnetic separation and passed through a magnet / ferrous separation operation (comprising shredding, demagnetization (discussed above), and clump screening) to produce ferrous scrap and oversize material, which is demagnetized and packaged as a spoke magnetic concentrate to be forwarded to a hub or chemical processing facility.

[0351] Referring to Fig. 17, which depicts the hub or chemical processing facility, magnet manufacturing rejects and whole magnets (e.g., from MRI machines and wind turbines), which is optionally demagnetized and forwarded to shredding and is combined with the spoke magnet concentrate (from Fig. 16), the decanted, washed and filtered wet swarf and dry swarf and subjected to fine (wet) milling to form a fine milled feed material, optionally oxidative roasting (as described herein), and the fine milled feed material subjected to acid leaching with a sulfuric acid lixiviant (as described herein) to form a REE rich pregnant leach solution and leach residue. The leach residue, which contains at least most of the tungsten-containing material in the fine milled feed material, is subjected to the alkaline leaching as discussed herein (e.g., as discussed in connection with Fig. 27) to recover the solubilized tungsten, and the pregnant leach solution is subjected to iron removal using a Goethite or other iron removal process to remove most of the iron (as described herein) and filtered to form an iron residue and filtrate containing most of the rare earths, nickel, and cobalt with a small amount of residual iron. The filtrate is subjected to optionally impurity solvent extraction or other similar process such as ion exchange (described herein) to form a rare earth rich solvent phase containing most of the rare earths and a base metal rich solvent phase containing most of the nickel and cobalt with most of the residual iron. The rare earth rich solvent phase or filtrate after iron removal is subjected to rare earth oxalate precipitation using oxalic acid (as described herein), the resulting slurry filtered, and the retentate containing the rare earth precipitates subjected to rare earth oxalate thermal decomposition (as described herein), optional selective impurity removal (as described herein) to remove impurities and form a substantially pure rare earth oxalate or pure rare earth oxide. The base metal rich solvent from the impurity solvent extraction operation or filtrate from rare earth oxalate precipitation is optionally subjected to primary pH neutralization using a suitable base, such as calcium hydroxide, and the neutralized solution filtered to form a filtrate containing most of the base metal and a retentate containing most of the gypsum. The filtrate is optionally passed to (“MHP”) precipitation using magnesium oxide (described herein) to precipitate the nickel and cobalt as hydroxides. The solution is optionally filtered to remove a retentate comprising mixed nickel and cobalt hydroxide precipitates (constituting most of the nickel and cobalt in the solution) and the filtrate containing most of the boron is optionally subjected to born recovery using a caustic and zinc salt (described herein) or ion exchange to form a boron product. The solution is subjected to final neutralization and filtration to form a final waste residue and clean water for recycle or discharge.

[0352] Another exemplary chemical process, according to embodiments of the present disclosure is depicted in Fig. 18. Fig. 18 depicts a process in which a magnet extract (such as mixed swarf, magnet manufacturing rejects, whole magnet and spoke magnet concentrate of Fig. 17) is subjected to acid leaching (such as the sulfuric acid leaching operation of Fig. 17). As noted, tungsten typically remains inert or forms insoluble tungstic acid and will be substantially insoluble in the leaching solution. The pregnant leach solution is subjected to solvent extraction or other similar process as noted above in Fig. 17 to remove iron or alternatively by adjusting the solution pH with calcium oxide, calcium hydroxide, calcium carbonate, magnesium oxide, magnesium hydroxide, magnesium carbonate, sodium hydroxide, or other alkaline reagents or minerals, or a combination thereof in an oxidative environment (i.e., in the presence of oxygen) achieved by the use of air, oxygen gas, or hydrogen peroxide, mixture of sulfur dioxide with oxygen or air gasses, permanganate, or other known oxidants in the industry or a combination thereof to precipitate iron, such as in the form of goethite or hematite, and other impurities. The iron barren pregnant leach solution after iron removal is subjected to rare earth precipitation using oxalic acid to precipitate most of the rare earths as oxalates as shown in Fig. 17, which precipitates are subjected to calcination and purification as described herein. The rare earth barren solution, containing most of the remaining base metals, is subjected to impurity removal to remove copper, aluminum, and other trace / residual iron as shown in Fig. 17, and the remaining nickel and cobalt in the resulting treated solution is precipitated as an MHP product as shown in Fig. 17 followed by boron removal by solvent extraction or ion exchange as shown in Fig. 17.

[0353] Although specific advantages have been enumerated above, various embodiments may include some, none, or all of the enumerated advantages.

[0354] Persons skilled in the art will appreciate that there are yet more alternative implementations and modifications possible, and that the above examples are only illustrations of one or more implementations. The scope, therefore, is only to be limited by the claims appended hereto and any amendments made thereto.

[0355] Tungsten Recovery

[0356] Referring to Fig. 25, an embodiment of a chemical processing unit 2352 is depicted.

[0357] The ground materials include magnetic material, such as ferromagnetic material (e.g., magnets, ferro tungsten alloy) and nonferromagnetic materials such as tungsten metal. The ground material may be either the ferromagnetic fraction (which will contain at least most and typically at least about 75% of the magnets and residual amounts of the tungsten-containing materials in the comminuted feed stream 2312) or tungsten-containing fraction (which will contain at least most and typically at least about 75% of the tungsten- containing materials and residual amounts of the magnets in the comminuted feed stream 2312) or the comminuted feed stream in Fig. 24 before separation of the ferromagnetic and nonferromagnetic materials. Typically, the ground material particles have a P₀ size ranging from about 10 to about 10,000 microns and more typically from about 100 to about 2500 microns.

[0358] The ground materials are acid leached in step 2504 as described in Figs. 13-14 and 17-18 to provide a slurry comprising a pregnant leach solution containing at least most and typically at least about 75% of the rare earth elements in the ground material and a solid residue containing at least most and typically at least about 75% of the tungsten and base metals in the ground material. The leach is typically performed in a stirred vessel. The common lixiviant is a mineral acid, such as sulfuric acid, hydrochloric acid, and the like. The leaching solution typically has pH during leaching ranging from about pH<0 to about pH<7.

[0359] The slurry is separated, such as by filtration with or without cake washing, decantation, settling, thickening, centrifugation, cyclone separation, elution or the like, into the separate liquid phase comprising the pregnant leach solution 310 and solid phase comprising the residue 312.

[0360] The rare earths and other valuable metals at least most of which are in the pregnant leach solution 310 along with relatively small amounts of base metals such as iron, copper, nickel, and boron, can be recovered from the pregnant leach solution as discussed in Figs.

[0361] 10, 13, 14, and 17-18.

[0362] The residue containing at least most and typically at least about 75% of the tungsten in the comminuted feed material may be physically separated as discussed above into a purified tungsten-containing residue fraction 2516 containing most of the tungsten in the ground material and a waste residue fraction. Because the residue fraction has a substantially uniform particle size, gravity separation techniques are typically employed rather than size separation.

[0363] The purified tungsten-containing residue fraction 2516 is further ground in a mill in step 2516 to form a tungsten-containing fraction (or tungsten enriched material having a high purity) 2520 for subsequent tungsten recovery. Typically, the particles after grinding have a P₀ size ranging from about 250 to about 5000 microns, more typically from about 50 to about 2000 microns, and more typically from about 100 to about 1000 microns to liberate the tungsten for recovery in later treatment steps described in Fig. 27. In some embodiments, alkaline leaching at a pH greater than pH 7 using an alkali or water-soluble base such as sodium hydroxide, sodium carbonate, or potassium hydroxide can be employed to selectively leach at least most and more typically at least about 75% of the tungsten from mixed feed material as a soluble tungstate compound, thereby leaving most of the rare earths and other base metals in the leach residue followed by acid leaching of the residue as discussed above to extract into or solubilize most of the rare earths in the residue. The alkaline lixiviant that extracts or solubilizes tungsten can be any suitable alkaline lixiviant, such as but not limited to sodium hydroxide or sodium carbonate, typically at a concentration of at least about 1% and more typically of least about 60%. Tungsten can be recovered from the pregnant leach solution by any suitable technique, including chemical precipitation as ammonium paratungstate, calcium tungstate, and the like, ion exchange, electrolytic deposition, solvent extraction, carbon adsorption, reduction, membrane filtration and thermal treatment.

[0364] In some embodiments, acid leaching can be employed to leach both tungsten and rare earths from a mixed feed material, such that at least most of the rare earths and tungsten are solubilized into a pregnant leach solution. The acid lixiviant can be a strong mineral acid, such as but not limited to sulfuric acid, as described above. To inhibit the formation of and surface passivation by tungstic acid, acid leaching of tungsten can be improved by adding phosphoric acid to form soluble heterotungstic acid, hydrogen peroxide to form water-soluble peroxytungstic acid, anther complexing agent, such as oxalic acid, or another tungsten solubilizing agent to form a soluble complex with tungsten. A suitable recovery technique, such as chemical precipitation, ion exchange, electrolytic deposition, solvent extraction, carbon adsorption, reduction, membrane filtration and thermal treatment can be used as discussed above to recover selectively the rare earths and tungsten as separate products from the pregnant leach solution.

[0365] In an embodiment, acid leaching of the mixed feed material to form a leached residue comprising at least most and more typically at least about 75% of the tungsten in the mixed feed material and a first pregnant leach comprising at least most and more typically at least about 75% of the rare earths, aluminum, iron, copper, zinc, cobalt, boron, and nickel (individually and collectively) in the mixed feed material can be performed before alkaline leaching of the leached residue to form a second pregnant leach comprising at least most and more typically at least about 75% of the tungsten in the mixed feed material and no more than about 25 wt.% and more typically no more than about 10 wt.% of the rare earths, aluminum, iron, copper, zinc, cobalt, boron, and nickel (individually and collectively) in the mixed feed material. The recovery circuit described above could be employed to separate rare earths from the dissolved aluminum, iron, copper, zinc, cobalt, boron, and nickel and a separate recovery circuit described herein could be employed to recover tungsten from the second pregnant leach solution.

[0366] In an embodiment, alkaline leach of the mixed feed material to form a first pregnant leach solution comprising at least most and more typically at least about 75% of the tungsten in the mixed feed material and a leached residue comprising at least most and more typically at least about 75% of the rare earths, aluminum, iron, copper, zinc, cobalt, boron, and nickel (individually and collectively) in the mixed feed material can be performed before acid leaching of the leached residue to form a second pregnant leach solution comprising at least most and more typically at least about 75% of the rare earths, aluminum, iron, copper, zinc, cobalt, boron, and nickel (individually and collectively) in the mixed feed material and no more than about 25% and more typically no more than about 10 wt.% of the tungsten in the mixed feed material. The recovery circuit described above could be employed to separate rare earths from the dissolved aluminum, iron, copper, zinc, cobalt, boron, and nickel and a separate recovery circuit described herein could be employed to recover tungsten from the first pregnant leach solution.

[0367] In an embodiment, after REE removal tungsten can be separated from other metals by adjusting the pH to a pH of about pH 7 to pH 8 to oxide the dissolved metal ions, adding a sulfide donor, and adjusting the pH to about pH 2 to about pH 3 to precipitate at least most of the metals leaving at least most of the tungsten in solution for subsequent recovery as ammonium paratungstate or precipitation as an alkaline earth metal (e.g., calcium) tungstate.

[0368] In an embodiment, after REE removal tungsten can be separated from other metals by adjusting the pH to a basic pH to oxidize the metals while adding a magnesium salt and ammonium solution, and adjusting the pH to an acidic pH to precipitate at least most of the metals leaving at least most of the tungsten in solution for subsequent recovery as ammonium paratungstate.

[0369] An embodiment of the chemical processing unit 2352 will now be discussed in connection with Fig. 27.

[0370] The tungsten-containing fraction from Figs. 24-26 is received, such as at a central chemical processing unit location geographically separate from the physical processing unit location, optionally.

[0371] The tungsten-containing fraction is oxidized_and digested, such as by alkali fusion of the tungsten-containing fraction (step 2704). Alkaline fusion of the tungsten-containing fraction can be carried out at high temperature (typically from about 400 to about 1,200°C) in a smelting or rotary furnace with NaOH / Na2SC>4 with air and one or more oxidizing agents, such as sodium nitrite or sodium nitrate with sodium carbonate and / or sodium hydroxide as flux and diluent. The desired product sodium tungstate then can be leached into the hot water. The mass of sodium nitrite or sodium nitrate typically ranges from about 0.5% to about 10% and more typically from about 1% to about 5% of the tungsten-containing fraction. Sodium carbonate stoichiometrically addition typically ranges from about 70% to about 140% and more typically from about 90% to about 115% depending on the tungsten concentration in the material. Alternatively, tungsten-containing fraction can be roasted in air / oxygen at high temperature (typically ranging from about 600 to about 1200 °C) to decompose most of the tungsten-containing materials into a mixture of tungsten oxide (e.g., tungsten oxide, tungsten (II) oxide, tungsten (III) oxide, tungsten (IV) oxide, tungsten (V) oxide, tungsten (VI) oxide, and mixtures thereof) and tungstate depending on tungsten-containing fraction’s composition (e.g., one or more of WO3, CoWO4, NiWC>4, Cr₂WO₆, CuWC>4, and mixtures thereof). Optionally, roasting in presence of sodium carbonate requires 150-200% stoichiometric addition. The resulting tungsten oxides can be leached using mineral acid leach to produce tungstic acid that can be further processed to produce ammonium para tungstate (APT) and optionally caustic process to produce sodium tungstate using stoichiometrically addition of NaOH typically ranges from about 70% to about 170% and more typically from about 90% to about 130%_depending on the tungsten concentration in the material. The pregnant leach solution from either process can be separated from the leach residue by solid / liquid separation techniques noted above and the separated pregnant leach solution is purified (step 2712). As noted, the leach residue contains most of the base metals, including Fe, Co, Ni, Cu, Ta, and mixtures thereof, which can either be converted into high-purity materials on site or, alternatively, by another specialized company. Subsequent purification of the pregnant leach solution can be done, for example, by ion exchange, solvent extraction, and other techniques known to those of skill in the art. Further purification can be done in the same way as described earlier. In the case of tungsten heavy metal scrap, it is more difficult to leach the binder due to its higher corrosion resistance. A combination of acids (e.g., phosphoric acid / sulfuric acid) to avoid precipitation of colloidal tungstic acid or additives like iron (III)-chloride must be used. The recovered tungsten 2714 can be crystallized from the pure stream as a tungsten salt, such as tungstic acid, yellow tungsten oxide (YTO), and / or ammonium para tungstate (APT) (step 516). APT can be thermally decomposed to produce a tungsten-containing product 520 comprising three major intermediate decomposition compounds produced from APT, namely ammonium meta tungstate, yellow tungsten oxide, and tungsten blue oxide. Tungsten metal powders can be produced via reduction of tungsten oxides.

[0372] Tungsten oxide can be reduced to tungsten metal by hydrogen reduction using hydrogen gas at elevated temperatures or carbon reduction using carbon as a reducing agent, typically in the form of coke.

[0373] In some embodiments, the APT can be formed by contacting the pregnant leach solution with ammonia to form and precipitate the APT. The APT is then separated using liquid / solid separation techniques to form a high purity APT. The separated APT can then be calcined at high temperature to remove at least most of the ammonia and water to provide a high purity tungsten product.

[0374] The methods and systems of the present disclosure are further described by way of the following illustrative, non-limiting experimental examples below.

[0375] EXPERIMENTAL

[0376] The following examples are provided to illustrate certain embodiments of the disclosure and are not to be construed as limitations on the disclosure, as set forth in the appended claims. All parts and percentages are by weight unless otherwise specified.

[0377] Example 1. Leachins.

[0378] Acid leaching comprises leaching of rare earth bearing magnet material with one or more of hydrochloric acid, nitric acid, sulphuric acid, formic acid, citric acid, or a combination thereof. The magnet material concentrate can be subjected to a leaching procedure characterized by the following: a pulp density of about 1% to about 30% by mass, an acid concentration of about 50 g / L to about 1600 g / L, a reaction time of about 0.5 hour to about 8 hours, a temperature up to about 100°C and reaction pH of about 0 to 2.5.

[0379] In a particular example, a magnet extract (composition of which is provided by Table 2) generated from processing of different types of mixed feed in a particular campaign was leached using about 10% pulp density, about 800 g / L sulphuric acid, about a 5 hour reaction time, about 80°C temperature, and a constant reaction pH of 1. Fig. 19 shows the percentage recovery of different metals and confirmed the quantitative recovery of REEs under proposed experimental conditions.

[0380] Leaching Reactions

[0381] 2Al(s) + 3H2SC>4(aq) = Ah(SO4)3(aq) + 3H2(g)

[0382] 2B(s) + 3H2SC>4(aq) = 2HsBO3(aq) + 3SC>2(g)

[0383] Ca(s) + H2SC>4(aq) = CaSC>4(aq) + H2(g)

[0384] Co(s) + FESC aq) = CoSC>4(aq) + H2(g)

[0385] CU(S) + H2SC>4(aq) = CuSC>4(aq) + H2(g)

[0386] 2Dy(s) + 3H2SC>4(aq) = Dy2(SO4)3(aq) + 3H2(g)

[0387] Fe(s) + H2SC>4(aq) = FeSC>4(aq) + H2(g)

[0388] 2Gd(s) + 3H2SC>4(aq) = Gd2(SO4)3(aq) + 3H2(g)

[0389] Mg(s) + H2SC>4(aq) = MgSC>4(aq) + EEfe)

[0390] 2Nd(s) + 3H2SC>4(aq) = Nd2(SC>4)3(aq) + 3H2(g)

[0391] Ni(s)+H2SC>4(aq) = NiSO4(aq)+H2(g)

[0392] 2Pr(s) + 3H2SC>4(aq) = Pr2(SC>4)3(aq) + 3H2(g)

[0393] 2Sm(s) + 3H2SC>4(aq) = Sm2(SO4)3(aq) + 3H2(g)

[0394] 2Tb(s) + 3H2SC>4(aq) = Tb2(SO4)3(aq) + 3H2(g)

[0395] Table 2. Composition of a mixed metal magnet extract.

[0396] Al B Ca Co Cu Dy Fe Gd Na Nd Pr Sm Tb % % % % % % % % % % % % %

[0397]

[0398] .26 0.97 0.22 1.08 0.19 0.98 66.48 0.05 0.02 27 0.3 0.96 0.33

[0399] The magnet extract produced from another campaign (composition of which is provided by Table 3) was subjected to study leaching kinetics under similar experimental conditions as mentioned above. The variation of time from 0.5 hours to 6 hours showed quantitative recovery of REEs. Fig. 20 demonstrates the percent recovery of the various metals over time, where REEs including gadolinium, samarium, neodymium, praseodymium, and terbium reached near 100% recovery levels.

[0400] Table 3. Composition of a mixed metal magnet extract.

[0401] Al B Co Cu Dy Eu Fe Gd Nd Ni Pr Sm Tb % % % % % % % % % % % % %

[0402]

[0403] 1.23 1.04 0.45 0.24 0.18 <0.01 61.99 0.39 18.5 0.02 5.14 0.58 0.03 Example 2. Iron Removal.

[0404] Iron can be removed by solvent extraction and precipitation as goethite or hematite. Iron removal comprises using calcium oxide, calcium hydroxide, calcium carbonate, magnesium oxide, magnesium hydroxide, magnesium carbonate, sodium hydroxide, or other alkaline reagents or minerals, or a combination thereof in an oxidative environment achieved using air, oxygen gas, or hydrogen peroxide, mixture of sulfur dioxide with oxygen or air gasses, permanganate, or other known oxidants in the industry or a combination thereof. The addition of copper ions and the use of solvent extraction may also be applied. To date, test work has achieved rem oval of up to about 99% iron in solution.

[0405] In an example, iron removal as goethite can be performed under the following experimental conditions: iron concentration from about 1 g / L to about 100 g / L, a pH equal to about pH 2.0 to about pH 6.0, about 50 wt.% hydrogen peroxide solution of about 2% to about 30 wt. % in the reaction, magnesium oxide slurry in the range of about 5% to about 70 wt. %, about 0.1% to 5% by weight of copper sulphate solution of about 25 g / L to about 100 g / L, temperature of about 30 °C to about 95 °C and reaction time of about 1 hour to about 10 hours.

[0406] In another particular example, a pregnant leach solution comprising about 58 g / L iron and about 27.2 g / L total rare earth elements (TREE) was subjected to goethite removal with the following conditions: a pH of about pH 2.5, about 20% hydrogen peroxide (50 wt.%), about 30% Mg(0H>2 for pH adjustment, about 0.5% of 84.2 g / L copper sulphate solution, about 80 °C temperature, and about a 5 hours reaction time. As a result, greater than about 99.5% iron was removed with less than about 7% loss of TREE.

[0407] Example 3. Oxalate Precipitation.

[0408] The pregnant leach solution (PLS) after the removal of impurities of one or more of iron, aluminum, copper, and zinc may be subjected to TREE oxalate precipitation. The precipitation is carried out at a pH of about pH 0.5 to about pH 5.5, a temperature up to about 90 °C, oxalic acid dosage ranging from about 50 to about 200% stochiometric addition relative to the TREE, and a reaction time in between about 5 minutes and about 2 hours.

[0409] In this specific example, the filtrate after impurities removal was tested for TREE precipitation. In this series of tests, precipitation conditions included: a pH equal to about pH 1.0, an oxalate dosage from about 70% to about 140% stochiometric, about a 500 rpm stirring speed, at room temperature, and a reaction time of about 30 minutes. TREE recovery increased from about 61.7% to about 99.9% by increasing the oxalate dosage from about 70% to about 140% stoichiometric. Results of this example are demonstrated in Fig. 21, in which TREE were selectively recovered relative to boron and cobalt.

[0410] Example 4. Calcination.

[0411] The oxalate precipitate may be subjected to selective calcination for impurity removal such as but not limited to nickel, cobalt, and iron oxalates by calcination at low temperatures or calcination at high temperature to recover rMREO. The calcination can be carried out in one or two steps at a temperature of about 150 °C to about 1200 °C, in presence of air, and reaction time ranging from about 30 minutes to about 8 hours.

[0412] In this specific example, calcination was performed with the following conditions: about 0.5 kg oxalate precipitate was calcined at about 1000 °C with an air flow of about 5 L / min for 4 hours. Greater than about 97.75% pure rMREO was recovered.

[0413] Example 5. Cobalt and Nickel Recovery.

[0414] Magnets may comprise cobalt and nickel which are valuable critical metals and can be separated from the process solution using solvent extraction and / or precipitation as a hydroxide using a reagent such as, but not limited to, lime or sodium hydroxide, magnesium oxide, calcium oxide, magnesium hydroxide, and calcium hydroxide producing a mixed cobalt-nickel hydroxide product.

[0415] The filtrate after rare earths precipitation and secondary iron removal, as disclosed herein, was subjected to cobalt and nickel precipitation. A mixed hydroxide precipitate (MHP) comprising cobalt and nickel can be generated under the following conditions: a pH ranging from about pH 5.5 to about pH 10, a magnesium oxide dosage ranging from about 50 to about 200% stochiometric addition, a temperature of about 25 °C to about 90 °C, and a reaction time of about 30 minutes to about 6 hours.

[0416] In this particular example, about 1 kg solution mass comprising about 6.2 g of cobalt and about 0.005 g of nickel) was subjected to MHP precipitation at a pH of about pH 6.6 to about pH 8.6, a 100% molar ratio MgO dosage, a temperature of about 60 °C for about 4 hours resulting in the recovery of 73 g MHP product comprising about 7.5 wt.% cobalt and about 0.01 wt. % nickel.

[0417] Example 6. Boron Removal

[0418] Boron is removed from the process solution using ion exchange or solvent extraction to produce products such as, but not limited to, zinc borate, boric acid, and / or sodium borate. In one embodiment, boron can be removed before or after MHP precipitation using ion exchange or solvent extraction. A boron-containing aqueous solution with a pH of about pH 6 to about pH 11 is treated with a boron- selective ion exchange resin, and boron is adsorbed onto the resin. The boron-selective ion exchange resins include commercially available resins including but not limited to Amberlite PWA10, Ambersep IRA743, Purolite SI 08, Bestion BD501 and Mitsubishi Diaion CRB05. The resulting resin can be eluted with one or more but not limited to hydrochloric acid, nitric acid, sulphuric acid, formic acid, citric acid, or a combination thereof.

[0419] In an example, a process solution bearing about 630 mg / L boron at pH of about pH 6.8 was passed at a flow rate of about 1 BV / h (2.5 mL / min) through a column (2.5 x 30 cm) with an H / D of about 12 containing Bestion BD501 resin and a bed volume (BV) of about 150 mL. A boron capacity of about 2.7 g / L was identified for Bestion BD501. The loaded boron was eluted with about 10 wt.% sulphuric acid and the resin could be regenerated using NaOH or NH4OH solution. The recovery of boron as boric acid was demonstrated from elute via crystallization. The resulting solid was analyzed using11B NMR in D2O as depicted in FIG. 22.

[0420] Example 7 - Tungsten Removal

[0421] Taptic Engine™ refers specifically to haptic engines in some electronic devices. It is also worth noting that phones and smart watches have haptic feedback modules that have REEs value along with tungsten. The possible composition from the breakdown of two taptic™ engines is in Fig.28-29.

[0422] It is to be understood the present disclosure includes processing of waste phones / watches / devices to liberate taptic and other haptic feedback modules for REE and tungsten (W) recovery using physical processing methods.

[0423] The presence of tungsten in Taptic Engines was confirmed using XRD technique. As shown in Figs. 29-30 below, the major phase is present as tungsten along with Fe-Ni alloying element (known as Permalloy having a nickel content of at least about 65 wt.% and more typically at least about 75 wt.% with the remainder being iron) which represents small, identified peaks in XRD pattern.

[0424] Study I

[0425] In one scenario, fine powder (<300 micron) of a mixed variety of Taptic Engines was digested and subjected to assay the elements present. The results are shown below in Table 4 in %wt.- Table 4. Target material composition

[0426] Element Feed Grade (%)

[0427] Al 0.05

[0428] B 0.15

[0429] Ca 0.01

[0430] Co 0.73

[0431] Cr 4.3

[0432] Cu 3.44

[0433] Dy 0.12

[0434] Fe 32.31

[0435] Gd 0.2

[0436] Ho 0.1

[0437] Mo 0.21

[0438] Nd 3.44

[0439] Ni 2.44

[0440] Pr 0.94

[0441] Tb 0.07

[0442] W 50.31

[0443]

[0444] Study II

[0445] Acid leaching comprises similar methodologies as described above for hub technology. The magnet material concentrate or the target material containing magnet and tungsten can be subjected to a leaching procedure including the following steps: a pulp density of about 1% to about 50% by mass, an acid concentration of about 50 g / L to about 1600 g / L, a reaction time of about 0.5 hour to about 8 hours, a temperature up to about 100° C, and reaction pH of about 0 to 4.

[0446] In a particular example, a target material (having the composition provided by Table 1 below) generated from processing of different types of mixed Taptic Engines in a particular campaign was leached using about 5-20% pulp density, about 500-1200 g / L sulphuric acid, about a l-5h reaction time, about 40-95 °C. temperature, and a constant reaction pH of 0.2-3.0. FIG. 31 below depicts the results of leaching of REEs from mixed taptic engines containing target material, shows the percentage recovery of different metals, and confirms the selective quantitative recovery of REEs under proposed experimental conditions.

[0447] In another leaching test under similar experimental conditions with a pH of about pH<1.5, dissolution of impurities increased and selectivity of REEs increased, e.g., at pH 1 there was a rise of 10% in iron dissolution.

[0448] Study III

[0449] The Wilfley Shaker Table is a gravity concentrating device that separates material based upon differing densities of the material. It is effective in concentrating high density minerals and has been used in mineral processing applications and found increasing popularity in the metals recycling sector. The shaking table used in the beneficiation of the mine field has the feature of separating precious and rare metals, especially in the structure of complex electronic wastes, from glass fiber and other plastic structures according to the density difference. Target magnetized material containing mixed feed generated from crushing and grinding of taptic engines was processed through the Wilfley Shaker Table (Table 5) to separate tungsten bearing alloy from magnet containing material along with other possible impurities.

[0450] Table 5. Experimental design for gravity separation of tungsten alloy from magnetized feed

[0451] Parameter Value

[0452] Particle size <150 pm - 1.18 mm

[0453] Wash water flow 7.6 L / min

[0454] Tilt angle 7°

[0455] Shaking frequency 100 Hz

[0456] Speed 12

[0457] Feed amount 250 g

[0458]

[0459] It is evident (Table 6) that in one single pass gravity separation, more than 90% of tungsten was recovered in concentrate phase with an enrichment factor of greater than 1. However, an average >85% of rare earths were recovered in the tailings phase with an average enrichment factor of >2. This indicates strong density-based separation and efficient recovery. Table 6. Results for tabling testing on mixed taptic engine feed

[0460] duct Mass Grade(%)

[0461] (%)

[0462] Al B Ca Co Cr Cu Dy Fe Mo Nd Ni Pr Tb W Z d 100

[0463] 0.05 0.15 0.01 0.73 4.3 3.44 0.12 32.31 0.21 3.44 2.44 0.94 0.07 50.31 0 ncentrate 64.46 0.01 0.08 0.01 0.32 2.63 2.05 0.01 23.98 0.11 0.72 2.57 0.2 0.02 70.62 0

[0464] lings 33.77 0.14 0.38 0.03 0.89 3.1 6.56 0.35 52.22 0.4 9.08 2.54 2.48 0.17 20.74 0

[0465] duct Mass Recovery(%)

[0466] (%)

[0467] Al B Ca Co Cr Cu Dy Fe Mo Nd Ni Pr Tb W Z d 100

[0468] 100 100 100 100 100 100 100 100 100 100 100 100 100 100 1 ncentrate 64.46 12.89 34.38 64.46 28.26 39.43 38.41 5.37 47.84 33.76 13.49 67.89 13.71 18.42 90.48 48

[0469] lings 33.77 94.55 85.54 101.30 41.17 24.34 64.39 98.49 54.57 64.32 89.13 35.15 89.09 82.00 13.92 42

[0470]

[0471] Study IV

[0472] The target feed material was first demagnetized at 600 °C for 3h and later was subjected to Wilfley Shaker Table for gravity -based separation of tungsten.

[0473] Table 7. Experimental design for gravity separation of tungsten alloy Parameter A B

[0474] Particle size <300 pm <300 pm

[0475] Wash water flow 3.8 L / min 3.8 L / min

[0476] Tilt angle 7° 6°

[0477] Shaking frequency 100 Hz 100 Hz

[0478] Speed 12-15 12-15

[0479] Feed amount 100 g 100 g

[0480]

[0481] Table 8. Results for tabling testing on mixed taptic engine feed

[0482] Mass (%)

[0483] Product

[0484] A B C*

[0485] Feed 100 100 100

[0486] Concentrate 72.54 74.2 77.15

[0487] Tailings 24.28 22.72 16.2

[0488]

[0489] *Feed material for this test was demagnetized and test conditions used were like test B Under the experimental conditions and results reported in Tables 7 and 8, >98% tungsten was recovered in concentrate resulting in high enrichment factor and separation efficiency.

[0490] Study V

[0491] A magnetic separator that divides a fine sample into magnetic and non-magnetic fractions to assess magnetic recovery and concentrate grade was used to separate tungsten from REE-containing magnets. The parameters used include a selected magnetic field strength (0.1-0.5 T), pulsation frequency (60-120 cycles / min), slurry flow rate (100-250 mL / min), motor rpm (500-1750 rpm), sample size (20-100 g) and continuous water flow. In one specific test, 47% of the mass was reported to tailings while rest mass to concentrate.

[0492] Route A

[0493] Intent: Dissolve REEs and base metals; keep tungsten (W) largely (more than 50% and more typically more than 75%) in solid residue (as metallic W or as WO3 / H2WO4 if pre- oxidized).

[0494] The steps of Route A are described below.

[0495] 1. Oxidation as pre-step (if W alloy is coarse or tightly bound to base metals such that the ability of an acidic leaching solution described above to dissolve base metals is substantially impaired). Perform an air / O2roast at a temperature ranging from about 350-1250 °C and more typically from about 500-1000 °C, at a residence time ranging from about 1-6 hr to oxidize at least most and more typically at least about 75% of W into WCh, at least most and more typically at least about 75% of Fe into Fe20s, and at least most Ni into NiO, thereby improving filterability and driving W into an acid-resistant form (e.g., tungstic acid) that is substantially insoluble in the acidic leaching solution. At least most of the oxidized Fe and Ni compounds will still dissolve in the acidic leaching solution during leaching. At least most of the WO3 / H2WO4 remains sluggish or substantially insoluble.

[0496] 2. Impurity control & REE recovery

[0497] Fe control: pH-controlled neutralization and precipitation as per Figs. 13, 14, and 18 described above

[0498] REE separation: as described in Figs. 23-24 and 26.

[0499] REE product: at least most and more typically at least about 75% of dissolved REE precipitates as oxalates, at least most and more typically at least about 75% of of which are then calcined to REO; as discussed above in Figs. 13, 14, and 18.

[0500] 3. Residue handling (W-rich)

[0501] Wash thoroughly; confirm W enrichment and low REE loss. If later W recovery is desired, proceed with alkaline leaching embodiment described earlier on the residue to dissolve at least most of the WO3 as soluble tungstate.

[0502] Route B

[0503] Alkaline leaching using an alkali as described above is performed first (to convert / dissolve at least most and more typically at least about 75% of W into a soluble tungstate; while keeping at least most and more typically at least about 75% of REEs as an undissolved solid)

[0504] Intent: Oxidize at least most of metallic W in W-Fe-Ni to WO3, then dissolve at least most W as Na2WO4in a strong alkali. At least most REEs / Fe / Ni oxides / hydroxides remain in the undissolved solid phase, enabling an orthogonal split. Afterwards, recover W (e.g., as APT) and leach at least most of the REEs with an acid as described above.

[0505] The steps of Route B are described below. 1. Pre-oxidation

[0506] Perform an air / O2roast of the feed material at a temperature of from about 250-1500 °C and more typically from about 400-1200 °C, at a residence time of about 2-15 h to oxidize at least most and more typically at least about 75% of W into WCh, at least most and more typically at least about 75% of Fe into Fe2O3, and at least most and more typically at least about 75% of Ni into NiO. Without this roast, metallic W is substantially insoluble to an alkaline leach and does not form a soluble tungstate.

[0507] 2. Alkaline oxidative leach (W dissolution)

[0508] Using an alkaline leaching solution comprising from about 0.5-10 M and more typically from about 2-4 M NaOH or other alkali, at a temperature of from about 80-95 °C, and a solid / liquid (S / L) ratio of from about 1: 1 to about 1:20 and more typically from about 1:8 to about 1: 12, at a residence time of about 1-3 h; and from about 1 to about 10 wt.% and more typically from about 3 to about 6 wt% H2O2 (to convert at least most and more typically at least about 75% W into peroxotungstate, thereby accelerating H2WO4 / WO3 dissolution).

[0509] WO3+2NaOH→Na2WO4+H2O

[0510] Solid-liquid separation

[0511] Filtrate A is predominantly composed of W (e.g., as Na2WO4) but may contain relatively low amounts of Mo, As, Si and other impurities.

[0512] Residue A is predominantly composed of REEs, iron and nickel oxides / hydroxides (which is at least most of the REEs, iron, and nickel in the original feed material): wash residue to remove carry-over W.

[0513] W recovery from Na2WO4is done by converting at least most and more typically at least about 75% of the tungsten compounds to ammonium tungstate — crystallize at least most and more typically at least about 75% ammonium tungstate into APT (ammonium paratungstate) by evaporation as described above or by pH swing. The ammonium tungstate-containing solution may be polished by solvent extraction or ion exchange as needed at remove at least most and more typically at least about 75% of any Mo, Si, or other impurities from the solution prior to APT formation.

[0514] REE recovery

[0515] Leach washed Residue A as described above and follow step 2 of route A.

[0516] As used herein, "at least one", "one or more", and "and / or" are open-ended expressions that are both conjunctive and disjunctive in operation. For example, each of the expressions "at least one of A, B, and C", "at least one of A, B, or C", "one or more of A, B, and C", "one or more of A, B, or C", " A, B, and / or C", and " A, B, or C" means A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B, and C together. When each one of A, B, and C in the above expressions refers to an element, such as X, Y, and Z, or class of elements, such as X1-Xn, Y1-Ym, and Z1-Zo, the phrase is intended to refer to a single element selected from X, Y, and Z, a combination of elements selected from the same class (e.g., X1and X2) as well as a combination of elements selected from two or more classes (e.g., Y1and Zo).

[0517] The preceding is a simplified summary of the disclosure to provide an understanding of some aspects of the disclosure. This summary is neither an extensive nor exhaustive overview of the disclosure and its various embodiments. It is intended neither to identify key or critical elements of the disclosure nor to delineate the scope of the disclosure but to present selected concepts of the disclosure in a simplified form as an introduction to the more detailed description presented below. As will be appreciated, other embodiments of the disclosure are possible utilizing, alone or in combination, one or more of the features set forth above or described in detail below.

[0518] A number of variations and modifications of the disclosure can be used. It would be possible to provide for some features of the disclosure without providing others.

[0519] The present disclosure, in various embodiments, configurations, or aspects, includes components, methods, processes, systems and / or apparatus substantially as depicted and described herein, including various embodiments, configurations, aspects, subcombinations, and subsets thereof. Those of skill in the art will understand how to make and use the present disclosure after understanding the present disclosure. The present disclosure, in various embodiments, configurations, and aspects, includes providing devices and processes in the absence of items not depicted and / or described herein or in various embodiments, configurations, or aspects hereof, including in the absence of such items as may have been used in previous devices or processes, e.g., for improving performance, achieving ease and\or reducing cost of implementation.

[0520] The concepts illustratively disclosed herein suitably may be practiced in the absence of any element which is not specifically disclosed herein. It is apparent to those skilled in the art, however, that many changes, variations, modifications, other uses, and applications of the disclosure are possible, and changes, variations, modifications, other uses, and applications which do not depart from the spirit and scope of the disclosure are deemed to be covered by the disclosure. The foregoing discussion of the disclosure has been presented for purposes of illustration and description. The foregoing is not intended to limit the disclosure to the form or forms disclosed herein. In the foregoing Detailed Description for example, various features of the disclosure are grouped together in one or more embodiments, configurations, or aspects for the purpose of streamlining the disclosure. The features of the embodiments, configurations, or aspects of the disclosure may be combined in alternate embodiments, configurations, or aspects other than those discussed above. This method of disclosure is not to be interpreted as reflecting an intention that the claimed disclosure requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment, configuration, or aspect. Thus, the following claims are hereby incorporated into this Detailed Description, with each claim standing on its own as a separate preferred embodiment of the disclosure.

[0521] Moreover, though the description of the disclosure has included description of one or more embodiments, configurations, or aspects and certain variations and modifications, other variations, combinations, and modifications are within the scope of the disclosure, e.g., as may be within the skill and knowledge of those in the art, after understanding the present disclosure. It is intended to obtain rights which include alternative embodiments, configurations, or aspects to the extent permitted, including alternate, interchangeable and / or equivalent structures, functions, ranges or steps to those claimed, whether or not such alternate, interchangeable and / or equivalent structures, functions, ranges or steps are disclosed herein, and without intending to publicly dedicate any patentable subject matter.

Claims

CLAIMSWhat is claimed is:

1. A method comprising:receiving a mixed feed comprising tungsten-containing material and magnets, wherein at least a portion of the magnets comprise rare earth elements;comminuting the mixed feed to form a comminuted feed stream;separating the comminuted tungsten-containing material from the comminuted magnets;recovering the rare earth elements from the comminuted magnets; and recovering the tungsten from the tungsten-containing material.

2. The method of claim 1, wherein the rare earth elements comprise one or more of neodymium, samarium, praseodymium, terbium, and dysprosium, wherein the comminuted magnets comprise one or more of rare earth elements, cobalt, and nickel and wherein the recovering of the rare earth elements comprises:acid leaching the comminuted magnets to form a pregnant leach solution comprising iron, one or more of neodymium, samarium, praseodymium, terbium, and dysprosium, and one or more of cobalt and nickel;removing at least a portion of the iron from the pregnant leach solution to form an iron-depleted solution comprising the one or more of neodymium, samarium, praseodymium, terbium, and dysprosium, and the one or more of cobalt and nickel and an iron-containing material;removing at least a portion of the one or more of neodymium, samarium, praseodymium, terbium, and dysprosium from the iron-depleted solution to form a rare earth product comprising one or more of neodymium, samarium, praseodymium, terbium, and dysprosium; andremoving at least a portion of the one or more of cobalt and nickel from the iron-depleted solution to form a metal product comprising one or more of cobalt and nickel.

3. The method of claim 2, wherein removing at least the portion of the one or more of neodymium, samarium, praseodymium, terbium, and dysprosium from the iron-depleted solution comprises:precipitating the one or more of neodymium, samarium, praseodymium, terbium, and dysprosium from the iron-depleted solution to form a rare earth precipitate; and calcining the rare earth precipitate to form a rare earth oxide.

4. The method of claim 3, wherein the one or more of neodymium, samarium, praseodymium, terbium, and dysprosium are precipitated as an oxalate or a carbonate or a salt.

5. The method of claim 2, wherein the comminuted magnets further comprise boron, the method further comprising:removing, after rare earth element removal and before or after removal of the one or more of cobalt and nickel, at least a portion of boron from the iron-depleted solution to form a boron metal product.

6. The method of claim 2, wherein the comminuted magnets further comprise impurities, the method further comprising:removing, after rare earth element removal and before removal of one or more of cobalt and nickel, at least most of the impurities from the iron-depleted solution, wherein the impurities comprise copper, aluminum, and trace iron.

7. A method comprising:receiving a mixed feed comprising tungsten-containing material and magnets having different chemical compositions, wherein at least a portion of the magnets comprise rare earth elements, wherein the rare earth elements comprise one or more of neodymium, samarium, praseodymium, terbium, and dysprosium;comminuting the mixed feed to form a comminuted feed stream;acid leaching the comminuted magnets to form a pregnant leach solution comprising at least most of the one or more of neodymium, samarium, praseodymium, terbium, and dysprosium in the rare earth magnets and a residue comprising at least most of the tungsten in the tungsten-containing material;oxidizing at least most of the tungsten in the tungsten-containing material; leaching the tungsten-containing material to form a pregnant leach solution comprising at least most of the oxidized tungsten in the tungsten-containing material; and recovering at least most of the tungsten from the pregnant leach solution.

8. The method of claim 7, wherein the magnets comprise iron and one or more of cobalt and nickel and wherein the pregnant leach solution comprises iron and at least most of the one or more of cobalt and nickel and further comprising:removing at least a portion of the iron from the pregnant leach solution to form an iron-depleted solution comprising the one or more of neodymium, samarium,praseodymium, terbium, and dysprosium, and the one or more of cobalt and nickel and an iron-containing material;removing at least a portion of the one or more of neodymium, samarium, praseodymium, terbium, and dysprosium from the iron-depleted solution to form a rare earth product comprising one or more of neodymium, samarium, praseodymium, terbium, and dysprosium; andremoving at least a portion of the one or more of cobalt and nickel from the iron-depleted solution to form a metal product comprising one or more of cobalt and nickel.

9. The method of claim 7, wherein the oxidizing is performed by alkaline fusion of the tungsten-containing material:

10. The method of claim 7, wherein the oxidizing is performed by roasting of the tungsten-containing material and wherein the recovering of at least most of the tungsten is performed by one or more of leaching, chemical precipitation, ion exchange, electrolytic deposition, solvent extraction, carbon adsorption, reduction, membrane filtration, crystallization and thermal treatment.

11. A method comprising:receiving a mixed feed comprising tungsten-containing material, plastics, and magnets having different chemical compositions, wherein at least a portion of the magnets comprise rare earth elements;comminuting the mixed feed to form a comminuted feed stream;floating at least most of the plastics in an overflow fraction while maintaining at least most of the comminuted tungsten-containing material and magnets in an underflow fraction;demagnetizing the comminuted magnets to form demagnetized comminuted magnets and optionally tungsten containing material;separating, by gravity separation, the optionally comminuted tungsten-containing material from the demagnetized comminuted magnets;recovering the rare earth elements from the separated comminuted magnets; and recovering the tungsten from the separated tungsten-containing material.

12. The method of claim 11, wherein the rare earth elements comprise one or more of neodymium, samarium, praseodymium, terbium, and dysprosium, wherein the comminuted magnets comprise one or more of cobalt and nickel, and wherein the recovering of the rare earth elements comprises:acid leaching the demagnetized comminuted magnets to form a pregnant leach solution comprising iron, one or more of neodymium, samarium, praseodymium, terbium, and dysprosium, and one or more of cobalt and nickel;removing at least a portion of the iron from the pregnant leach solution to form an iron-depleted solution comprising the one or more of neodymium, samarium, praseodymium, terbium, and dysprosium, and the one or more of cobalt and nickel and an iron-containing material;removing at least a portion of the one or more of neodymium, samarium, praseodymium, terbium, and dysprosium from the iron-depleted solution to form a rare earth product comprising one or more of neodymium, samarium, praseodymium, terbium, and dysprosium; andremoving at least a portion of the one or more of cobalt and nickel from the iron-depleted solution to form a metal product comprising one or more of cobalt and nickel.

13. The method of claim 12, wherein removing at least the portion of the one or more of neodymium, samarium, praseodymium, terbium, and dysprosium from the iron-depleted solution comprises:precipitating the one or more of neodymium, samarium, praseodymium, terbium, and dysprosium from the iron-depleted solution to form a rare earth precipitate; and calcining the rare earth precipitate to form a rare earth oxide.

14. The method of claim 13, wherein the one or more of neodymium, samarium, praseodymium, terbium, and dysprosium are precipitated as an oxalate or a carbonate or a salt.

15. The method of claim 12, wherein the demagnetized comminuted magnets further comprise boron, the method further comprising:removing, after rare earth element removal and before or after removal of the one or more of cobalt and nickel, at least a portion of boron from the iron-depleted solution to form a boron metal product.

16. The method of claim 12, wherein the demagnetized comminuted magnets further comprise impurities, the method further comprising:removing, rare earth element removal and before removal of the one or more of cobalt and nickel, at least most of the impurities from the iron-depleted solution, wherein the impurities comprise copper, aluminum, and trace iron.

17. The method of claim 11, wherein the recovering of the tungsten comprises: oxidizing at least most of the tungsten in the tungsten-containing material.

18. The method of claim 17, wherein the oxidizing is performed by alkaline fusion of the tungsten-containing material:

19. The method of claim 17, wherein the oxidizing is performed by roasting of the tungsten-containing material.

20. A method comprising:receiving a mixed feed comprising tungsten-containing material in a nonferromagnetic portion and magnets in a ferromagnetic portion, wherein at least a portion of the magnets comprise rare earth elements;comminuting the mixed feed to form a comminuted feed stream;separating the comminuted tungsten-containing material in the non-ferromagnetic portion from the comminuted magnets in the ferromagnetic portion;recovering the rare earth elements from the comminuted magnets in the ferromagnetic portion; andrecovering the tungsten from the tungsten-containing material in the nonferromagnetic portion.

21. A method comprising:receiving a mixed feed comprising, in a ferromagnetic portion, tungsten-containing material and magnets, wherein at least a portion of the magnets comprise rare earth elements;comminuting the mixed feed to form a comminuted feed stream;recovering the rare earth elements from the comminuted magnets in the ferromagnetic portion; andrecovering the tungsten from the tungsten-containing material in the ferromagnetic portion.

22. A method comprising:receiving a mixed feed comprising tungsten-containing material and magnets, wherein at least a portion of the magnets comprise rare earth elements, wherein the rare earth elements comprise one or more of neodymium, samarium, praseodymium, terbium, and dysprosium;comminuting the mixed feed to form a comminuted feed stream;acid leaching the comminuted magnets in the presence of a tungsten solubilizing agent to form a pregnant leach solution comprising at least most of the one or more of neodymium, samarium, praseodymium, terbium, and dysprosium in the rare earth magnets and the tungsten in the tungsten-containing material and a leached residue; and recovering at least most of the rare earth elements and tungsten from the pregnant leach solution.

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