Apparatus and process for selective liberation and mechanical recycling of electronic waste to recover valuable elements

Abstract

Embodiments can relate to techniques for recycling metals from electronic waste (e.g. waste printed circuit boards (WPCBs), consumer electronics, industrial electronics, etc.). Specifically, embodiments can relate to a method for processing product to liberate target materials within that product in an optimized manner. An exemplary method can involve generating a mix by subjecting the product to one or more comminution techniques to reduce one or more components of the product to particles having, on average, a predetermined size, and then subjecting the particles to additional comminution and / or separation techniques. The first round of comminution used to reduce the components to the predetermined size can lead to greater efficiencies and optimized liberation of target materials.

Description

Atty. Ref. No. 0073605-000845 APPARATUS AND PROCESS FOR SELECTIVE LIBERATION AND MECHANICAL RECYCLING OF ELECTRONIC WASTE TO RECOVER VALUABLE ELEMENTS CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This patent application is related to and claims the benefit of priority of U.S. provisional patent application no. 63 / 519,376, filed on August 14, 2023, the entire contents of which is incorporated herein by reference. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT

[0002] This invention was made with government support under Grant No. DE-EE0007897 awarded by the U.S. Department of Energy. The Government has certain rights in the invention. FIELD OF THE INVENTION

[0003] Embodiments relate to techniques for recycling plastics and metals from electronic waste (e-waste) (e.g. waste printed circuit boards (WPCBs), consumer electronics, industrial electronics, etc.) and other waste streams including but not limited to solar panels, batteries (e.g., black mass), wind turbines, interconnect industry waste, capacitator, plastic, automative, glass, metal-scrap, municipal solid waste, incinerated ash, catalytic converters, truck, industrial and other catalytic converters, fuel cells, rare earth magnet recycling, etc. Specifically, embodiments can relate to a method for processing product to liberate target materials within that product in an optimized manner, and separate components based on the differences in their specific gravity. BACKGROUND OF THE INVENTION

[0004] E-waste, constituting 8% of municipal waste, is a global concern. Currently, 83% of e- waste, valued at $47 billion, ends up in landfills, representing a significant loss of critical materials essential for the transition to clean energy and a carbon-free future. Within this fastest- growing waste category, WPCB contribute approximately 3% to the 45 Mt / year of global e- waste. Despite their economic attractiveness due to the high base and precious metal contents, WPCB pose significant challenges for recycling. The recovery of metals from e-waste, and WPCB involves multi-stage processes, with liberation being the most critical. Conventional comminution methods involving ultra-fine size reduction face challenges due to the hardness andAtty. Ref. No. 0073605-000845 tenacity of these materials. High energy requirements, agglomeration, temperature increases, the generation of fine particles, and loss of precious metals complicate the liberation process. Alternative chemical methods such as thermolysis, gasification, and supercritical fluid depolymerization for the liberation of non-metals from metals also entail environmental concerns regarding the potential release of toxic flame retardants. Mechanical-physical treatments, such as crushing, cyclone air separation, and electrostatic separation, have been found to achieve high Cu recovery but with significant loss of precious metals. Sorting technologies are inefficient in treating fine particle size (e.g., less than 5 mm). Various advanced technologies, including direct hydrometallurgical and pyrometallurgical processes, aim to recover precious metals. However, these energy- and resource-intensive methods carry drawbacks such as chemical consumption, toxic gas emissions, and environmental contamination. SUMMARY OF THE INVENTION

[0005] An exemplary embodiment can relate to a method for liberating material from a product. The method can involve performing work on the product to generate a mix comprising components of the product having particles that are, on average, a predetermined size. The method can involve separating a majority of the components from the mix based on a density separation technique. The method can involve subjecting the remaining components of the mix to one or more comminution techniques, and separating additional components from the mix.

[0006] In some embodiments, performing work on the product can involve shredding, cutting, chopping, mincing, etc.

[0007] In some embodiments, the method can involve separating a majority of the components from the mix.

[0008] In some embodiments, the predetermined average size of the particles can be about 0.5 mm to about 101.6 mm.

[0009] In some embodiments, the one or more comminution techniques can include shredding, rod milling, roller grinding, ball milling, hammer milling, ring milling, impact milling, rotary drum milling, knife milling, jaw milling, rotor milling, cutter milling, chip milling, disc pulverizer, high-pressure grinding rolls (HPGR) and / or attrition milling.

[0010] In some embodiments, subjecting the remaining components of the mix to one or more comminution techniques can involve shredding. rod milling, roller grinding, ball milling,Atty. Ref. No. 0073605-000845 hammer milling, ring milling impact milling, rotary drum milling, knife milling, jaw milling, rotor milling, cutter milling, chip milling, disc pulverizer, high-pressure grinding rolls (HPGR) and / or attrition milling the remaining components that are greater than the predetermined size.

[0011] In some embodiments, the components can include a malleable material and a brittle material.

[0012] In some embodiments, separating additional components from the mix can involve size separation, gravity separation, magnetic separation, etc.

[0013] In some embodiments, the method can involve subjecting the separated out components to one or more material processing techniques to recover and / or purify the separated out components.

[0014] In some embodiments, the one or more material processing techniques to recover and / or purify the separated out components can include a physical or physicochemical process(e.g., size classification, magnetic, electrostatic, flotation, sorting, eddy current), a hydrometallurgical process (e.g., leaching, deep eutetic solution, solvent extraction, ionic liquid, ion adsorbtion, precipitation, etc.) and / or a pyrometallurgical process (e.g., smelting).

[0015] In some embodiments, the components can include Cu, Al, Au, Ag, Pd, Rh, Ru, Pt, Re, Fe, lanthanides, Sc, Y, Ta, Li, Co, Ni, Mn, Si, plastics, and / or glass.

[0016] In some embodiments, the product can include a printed circuit board, electronic waste, a consumer electronic, an industrial electronic, a solar panel, interconnect industry waste, a capacitator, plastic, automative scrap, glass, metal-scrap, municipal solid waste, incinerated ash, thermolyzer product, a catalytic converter, a black mass, etc.

[0017] An exemplary embodiment can relate to a method for liberating material from a product. The method can involve performing work on the product to generate a first mix comprising components of the product having particles that are, on average, a first predetermined size. The method can involve separating a majority of the components from the first mix based on a density separation technique. The method can involve comminution of the first mix to generate a second mix comprising components of the product having particles that are, on average, a second predetermined size. The method can involve separating a majority of the components from the second mix based on a density separation technique. The method can involve subjecting theAtty. Ref. No. 0073605-000845 remaining components of the first mix and / or the second mix to one or more comminution techniques, and separating additional components from the first mix and / or the second mix.

[0018] In some embodiments, the first predetermined average size of the particles can be about 0.5 to about 101.6 mm. In some embodiments, the second predetermined average size of the particles is about 0.150 mm to about 0.5 mm.

[0019] In some embodiments, the one or more comminution techniques can include rod milling, roller grinding, ball milling, hammer milling, and / or ring milling.

[0020] In some embodiments, subjecting the remaining components of the first mix and / or the second mix to one or more comminution techniques can involve rod milling, roller grinding, ball milling, hammer milling, and / or ring milling the remaining components that are greater than the predetermined size.

[0021] In some embodiments, performing work on the product can involve shredding, cutting, chopping, and / or mincing.

[0022] In some embodiments, the components can include a malleable material and a brittle material.

[0023] In some embodiments, separating additional components from the first mix and / or the second mix can involve size separation, gravity separation, and / or magnetic separation.

[0024] In some embodiments, the method can involve subjecting the separated out components to one or more material processing techniques to recover and / or purify the separated out components.

[0025] In some embodiment, the method can involve subjecting the product and / or components to a mechanical treatment, a heating treatment, thermal treatment, a thermolysis treatment, a pyrolysis treatment, a gasification treatment, a supercritical fluid depolymerization treatment, a liquid nitrogen treatment, and / or a delamination treatment (e.g., using various lixiviants). This can be done to facilitate applying the inventive methods disclosed herein to untreated materials, treated materials, or both.

[0026]

[0027] Further features, aspects, objects, advantages, and possible applications of the present invention will become apparent from a study of the exemplary embodiments and examples described below, in combination with the Figures, and the appended claims.Atty. Ref. No. 0073605-000845 BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and other objects, aspects, features, advantages and possible applications of the present innovation will be more apparent from the following more particular description thereof, presented in conjunction with the following drawings. Like reference numbers used in the drawings may identify like components.

[0029] FIG. 1 is an exemplary process flow diagram for an embodiment of the method for liberating material from a product.

[0030] FIG. 2 is an exemplary schematic of a size-by-size density fraction process.

[0031] FIG. 3 shows an exemplary schematic of a size-by-size density fractionation of comminution product process.

[0032] FIG. 4 shows a size fractionation of char-metal mixture plot.

[0033] FIGS. 5A and 5B show size-by-size base metals content and distribution plots.

[0034] FIGS. 6A and 6B show size-by-size PGM content and distribution plots.

[0035] FIGS. 7A and 7B show size-by-size Fe content and distribution plots.

[0036] FIG. 8 shows a size-by-size comparison of intensity of diffraction peaks.

[0037] FIG. 9 shows a size-by-size density fractionation weight distribution plot.

[0038] FIG. 10A and 10B show Cu distribution and concentration in the sized density fractions plots.

[0039] FIGS. 11A and 11B show Al distribution and concentration in the sized density fractions plots.

[0040] FIGS. 12A, 12B, 12C, 12D, 12E, and 12F show PGMs distribution and concentration in the sized density fractions plots.

[0041] FIGS. 13A and 13B show Fe distribution and concentration in the sized density fractions plots.

[0042] FIG. 14 shows a microscopic view of the -25.4+12.7 mm size fraction.

[0043] FIG. 15 shows a microscopic view of the -12.7+4.76 mm size fraction.

[0044] FIG. 16 shows an SEM-EDS image and distribution maps for individual elements (base metals, Fe and Si) of -4.76+1.19 mm size fraction.

[0045] FIG. 17 shows an SEM-EDS image and distribution maps for individual elements (base metals, Fe and Si) of -1.19+0.595 mm size fraction.Atty. Ref. No. 0073605-000845

[0046] FIG. 18 shows an SEM-EDS image and distribution maps for individual elements (base metals, Fe and Si) of -0.595+0.297 mm size fraction.

[0047] FIG. 19 shows an SEM-EDS image and distribution maps for individual elements (base metals, Fe and Si) of -0.297+0.149 mm size fraction.

[0048] FIG. 20 shows an SEM-EDS image and distribution maps for individual elements (base metals, Fe and Si) of -0.149 mm size fraction.

[0049] FIG. 21 shows a calculated Cu, Al, and total metals degree of liberation plot.

[0050] FIG. 22 exemplary weight distribution of size-by-size density fractionation of the rod mill product ground in four different milling time.

[0051] FIGS. 23A, 23B, 23C, and 23D show plots for base metals distribution and concentration in the sized density fractions in four different milling time.

[0052] FIGS. 24A, 24B, 24C, 24D, 24E, and 24F show plots for PGMs distribution and concentration in the sized density fractions in four different milling time.

[0053] FIG. 25 shows an SEM-EDS image and distribution maps for individual elements (Al, Si, and C) of -0.595 mm +0.149 mm size fraction and 2.95 float for milling time of 5 min.

[0054] FIG. 26 shows an SEM-EDS image and distribution maps for individual elements (base metals, Si, and C) of -0.595 mm +0.149 mm size fraction and 2.95 sink for milling time of 5 min.

[0055] FIG. 27 shows an SEM-EDS image and distribution maps for individual elements (Al, Si, and C) of -0.595 mm +0.149 mm size fraction and 2.95 float for milling time of 10 min.

[0056] FIG. 28 shows an SEM-EDS image and distribution maps for individual elements (base metals, Si, Fe, and C) of -0.595 mm +0.149 mm size fraction and 2.95 sink for milling time of 10 min.

[0057] FIG. 29 shows an SEM-EDS image and distribution maps for individual elements (Al, Si, and C) of -0.595 mm +0.149 mm size fraction and 2.95 float for milling time of 15 min.

[0058] FIG. 30 shows an SEM-EDS image and distribution maps for individual elements (Cu) of -0.595 mm +0.149 mm size fraction and 2.95 sink for milling time of 15 min.

[0059] FIG. 31 shows an SEM-EDS image and distribution maps for individual elements (Al, Si, and C) of -0.595 mm +0.149 mm size fraction and 2.95 float for milling time of 25 min.

[0060] FIG. 32 shows an SEM-EDS image and distribution maps for individual elements (Cu) of -0.595 mm +0.149 mm size fraction and 2.95 sink for milling time of 25 min.Atty. Ref. No. 0073605-000845

[0061] FIG. 33 shows a plot of calculated Cu, Al, and total metals degree of liberation of comminution products.

[0062] FIG. 34 shows an exemplary conceptualized liberation and physical separation processes to recover base metals and PGM from WPCBs.

[0063] FIG. 35 shows an exemplary jigging operation principle schematic view and its products by layers.

[0064] FIG. 36 shows a schematic view of MGS and its products.

[0065] FIG. 37 shows a plot for weight distribution of jig products.

[0066] FIGS. 38A and 38B show 1base metals distribution and concentration in the jig products.

[0067] FIG. 39 show a plot of weight distribution of shaking table products.

[0068] FIGS. 40A, 40B, 40C, and 40D show plots for base metals distribution and concentration in the shaking table products.

[0069] FIGS, 41A, 41B, 41C, 41D, 41E, and 41F show plots for PGMs distribution and concentration in the shaking table products.

[0070] FIGS. 42A and 42B show plots of Fe distribution and concentration in the shaking table products.

[0071] FIG. 43 shows a plot for weight distribution of MGS products.

[0072] FIGS. 44A, 44B, 44C, and 44D show plots for base metals distribution and concentration in the MGS products.

[0073] FIGS. 45A, 45B, 45C, 45D, 45E, and 45F show plots for PGMs distribution and concentration in the MGS products.

[0074] FIGS. 46A and 46B show plots of Fe distribution and concentration in the MGS products.

[0075] FIGS. 47, 48, and 49 show exemplary processes for embodiments of the techniques disclosed herein. DEFINITIONS

[0076] As used herein, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to a "comminution technique" includes aspects having two or more such comminution aspects unless the context clearly indicates otherwise.Atty. Ref. No. 0073605-000845

[0077] Ranges can be expressed herein as from "about" one particular value and / or to "about" another particular value. When such a range is expressed, another aspect includes from the one particular value and / or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent "about," it will be understood that the particular value forms another aspect. It should be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint. Similarly, when values are expressed as approximations, by use of the antecedent "about," it will be understood that the particular value forms another aspect. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint and independently of the other endpoint. For instance, unless stated otherwise, the term "about" means within 25% (e.g., within 20% or 10%) of the particular value modified by the term "about."

[0078] Throughout this disclosure, various aspects of the invention can be presented in a range format. It should be understood that the description in range format is merely for convenience and brevity and should not be construed as an inflexible limitation on the scope of the invention. Accordingly, the description of a range should be considered to have specifically disclosed all the possible subranges as well as individual numerical values within that range. For example, description of a range such as from about 0.5 to about 101.6 should be considered to have specifically disclosed subranges such as from about 0.5 to about 1.0, from about 1.0 to about 10.0, from about 10.1 to about 50.0, from about 50.0 to 100.0, from about 100.0 to about 101.6, etc. as well as individual numbers within that range, for example, 0.5, 1.0, 10.0, 50.0, 100.0, etc. and any whole and partial increments therebetween. This applies regardless of the breadth of the range.

[0079] It is also to be understood that the terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting. As used in the specification and in the claims, the term "comprising" can include the aspects "consisting of" and "consisting essentially of."

[0080] For the terms "for example" and "such as," and grammatical equivalences thereof, the phrase "and without limitation" is understood to follow unless explicitly stated otherwise.Atty. Ref. No. 0073605-000845

[0081] As used herein, the term or phrase "effective," "effective amount," or "conditions effective to" refers to such amount or condition that is capable of performing the function or property for which an effective amount or condition is expressed. As will be pointed out below, the exact amount or particular condition required will vary from one aspect to another, depending on recognized variables such as the materials employed and the processing conditions observed. Thus, it is not always possible to specify an exact "effective amount" or "condition effective to." However, it should be understood that an appropriate effective amount will be readily determined by one of ordinary skill in the art using only routine experimentation.

[0082] While aspects of the present invention can be described and claimed in a particular statutory class, such as the system statutory class, this is for convenience only and one of ordinary skill in the art will understand that each aspect of the present invention can be described and claimed in any statutory class. Unless otherwise expressly stated, it is in no way intended that any method or aspect set forth herein be construed as requiring that its steps be performed in a specific order. Accordingly, where a method claim does not specifically state in the claims or descriptions that the steps are to be limited to a specific order, it is in no way intended that an order be inferred in any respect. This holds for any possible non-express basis for interpretation, including matters of logic with respect to arrangement of steps or operational flow, plain meaning derived from grammatical organization or punctuation, or the number or type of aspects described in the specification. DETAILED DESCRIPTION OF THE INVENTION

[0083] The following description is of exemplary embodiments that are presently contemplated for carrying out the present invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of describing the general principles and features of the present invention. The scope of the present invention is not limited by this description.

[0084] Referring to FIG. 1, embodiments can relate to a method for processing product to liberate target materials within that product in an optimized manner. The optimization can be the most effective liberation of material with the minimal amount of energy used. Energy use can encompass energy consumption, processing steps, processing time, etc. Optimization can factor costs (e.g., financial, environmental, consumption, etc.), salvage value (e.g., market value of the target component), opportunity costs, etc. As will be demonstrated herein, embodiments of theAtty. Ref. No. 0073605-000845 method can be used to hone in one a single comminution technique to reduce component of the product to a target particle size. That single comminution technique and target particle size can the optimal parameters to achieve the most effective liberation of material with the minimal amount of energy used. Other material processing can be done to recover, refine, purify, etc. the liberated material, but utilizing the optimized comminution technique to generate the target particle size as the initial step (or one of the initial steps) can realize the greatest yield with the minimal amount of energy usage.

[0085] It is contemplated for the product to be a printed circuit board. For instance, the product can be a waste printed circuit board. It may be desirable to recycle (e.g., reuse, salvage, sell, etc.) the printed circuit board, one or more components of the printed circuit board, etc. In this regard, it may be desirable to liberate one or more components of the printed circuit board from the other components so that the liberated component can be separated out. The separated out component(s) can be the material desired for recycling or the be material that is deemed an impurity and should be removed and discarded. It is understood that the product can be other types of electrical components including end-of-life electronic waste or other products including but not limited to solar panels, batteries (e.g., black mass), wind turbines, interconnect industry waste, capacitator, plastic, automative scrap, glass, metal-scrap, municipal solid waste, incinerated ash, catalytic converters, truck, industrial and other catalytic converters, fuel cells, and rare earth magnet recycling that includes components for which techniques disclosed herein are applicable.

[0086] With the example of the product being a printed circuit board, the product can contain malleable components and brittle components. For instance, the malleable components can include Cu, Al, Au, Ag, Pd, Rh, Ru, Pt, Re, Fe, etc. The brittle components can include Si, Ge, Ga, etc. Other components can include plastic based material, carbon based material, volatiles, polymers, resins, etc., which may be referred to as impurities for the purposes of liberating and recovering the malleable and / or brittle components from the product. It is contemplated for the target components (e.g., the components desired for recycling and thus desired to be liberated) to be Cu, Al, Au, Ag, Pd, Rh, Ru, Pt, and Re, lanthanides (i.e., La,Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb,Dy, Ho, Er, Tm, Yb, Lu), Sc, Y, Ta, Li, Co, Ni, Mn. Thus, optimal processing of the product can be using one or more comminution techniques to reduce the product to particles having aAtty. Ref. No. 0073605-000845 target size to most effectively liberate one or more of these elements. This target size can be used to liberate the most target components with the minimal use of energy.

[0087] For instance, the method can involve first size reduction to manageable sizes (e.g., using a shredder), followed by size classification to separate the liberated materials (if any) and one or more specific gravity separation for the liberated fractions, and generating a mix which is not liberated for the second stage liberation through comminution. This could be followed or preceded by other separation techniques, such as (e.g., magnetic, electrostatic, flotation, sorting), hydrometallurgical (e.g., leaching, deep eutetic solution, solvent extraction, ionic liquid, ion adsorbtion, precipitation, etc.) or pyrometallurgical (e.g., smelting) processes for further treatment, and / or purification, and / or metal production.

[0088] For instance, the method can involve generating a mix by subjecting the product to one or more comminution techniques utilizing the differences in ductility indices and the size they appear in the WPCB to liberate one or more components of the product to particles sizes which can be processed using specific gravity separation. For instance, the size range having a size of greater than 0.5 mm may be most beneficial or optimal for a WPCB, for example. It is contemplated for each of the components to be liberated or reduced to particles having a size range, but it understood that the process can involve reducing a certain amount (e.g., an average, a majority, a certain percentage, etc.) of the components to the size range. It is further contemplated for the initial particle liberation via comminution to be a single comminution technique, but it is understood that more than one comminution technique applying impaction or compaction (which could be mixed by friction) to liberate materials based on the differences in ductility indices can be used technique. For instance, the initial particle reduction comminution after shredding to reduce one or more components of the product to particles having the average size can be rod milling. However, this initial comminution (and other comminutions if they are used) can include rod milling, roller grinding, ball milling, hammer or ring milling, etc. This can be applied for both the untreated or treated materials using various techniques (such as thermal, thermolysis, pyrolysis, gasification, and supercritical fluid depolymerization, liquid nitrogen, delamination using various lixiviants, etc.).

[0089] With the product being a printed circuit board, using rod milling comminution to liberate the components to particles having an average size of greater 0.5 mm can facilitate effectiveAtty. Ref. No. 0073605-000845 liberation of one or more malleable components with the minimal use of energy. For instance, a majority of Cu and Al can be liberated when the product is subjected to a rod milling comminution to liberate the product to different particle size ranges. The liberated components can be separated from the mix using size separation techniques (e.g., sieving, cyclones, etc.). The liberated coarse size fraction (e.g., greater than 0.05 - 0.5 mm) are subjected to to one or more specific gravity separation (including but not limited to wet or air Jig, dense medium separation, FGX, shaking table, air table, spiral, combination thereof, etc.) to separate out plastics and resins (low density), Si, glass, Al (medium density), and mix of Cu, Fe, precious metals, and other heavy metals. Any method known in the art could be used for dewatering (if needed), and additional treatment using physical (e.g., magnetic separation, electrostatic, sorting, flotation, etc.), hydrometallurgical (e.g., leaching, Deep Eutetic Solution, Solvent Extraction, Ionic Liquid, etc.) or pyrometallurgical (e.g., smelting) processes for the generated product streams. The liberated fine size fraction (e.g., smaller than 0.05-0.15 mm) could be subjected to the enhanced specific gravity separation units (e.g., Multi gravity separator (MGS), Knelson, Falcon, etc.) to separate out the high density metals (mainly Cu, and precious metals and other heavy valuable metals) from medium density (e.g., Al, Si, etc) and light density (e.g., remaining plastic, char and carbon materials, etc.). The application of specific gravity separation units could be performed at multi-stages to enhance the recovery and grade of the products. The specific gravity separations for various size fractions could be followed or preceded by other techniques, including but not limited to size separation, dewatering, magnetic separation, electrostatic separation, flotation, or any known state-of-the-art hydro and pyrometallurgical processing methods.

[0090] The resultant mix can be subjected to additional comminution for further liberation followed by specific gravity separation if desired.

[0091] Thus, one or more stages or rounds of comminution can be performed. Each stage increasingly liberates the components in particle size ranges. There can be one, two, three, four, five, etc. stages or rounds of comminution.

[0092] Before, during, and / or after one or more comminution techniques to reduce the particle size to the targeted average size(s), the product or the mix(es) can be subjected to one or more specific gravity separation to separate the components based on the differences in their specificAtty. Ref. No. 0073605-000845 gravity. The specific gravity separation can be combined with other material processing to improve liberation, recovery, grade, refinement, purification, etc. to generate efficiencies, to meet certain design criteria, to generate or improve material properties, etc. This can include interrupting the comminution to perform a filtering or separating technique, performing an ashing, thermolysis, pyrolysis, heating and / or cooling and so on technique to facilitate the removal of impurities, etc. This could be also involved with pretreatment processing. In addition, it is understood that one comminution technique can be used to generate the first mix while another comminution technique can be used to generate the second mix. In addition, it is understood that one comminution technique can be used to partially reduce the particle size while another comminution technique can be used to liberate the particles at different size ranges or complete the particle reduction to the target average particle size. In addition, it is understood that the selection of the comminution technique, selection of the target average particle size, if / when to perform other material processing, etc. can be based on optimizing liberation of a single component from the product, optimizing liberation of more than one component of the product, optimizing liberation of a predetermine percentage(s) of one or more components of the product, etc. It is also understood that the cost of energy and salvage value of the components can play a factor in which components to target. Thus, optimization may be focused on liberating Au, Ag, Pd or Rh, instead of Cu and Al, for example. This may require an adjustment of the target average particle size, for example.

[0093] Exemplary processing steps can be appreciated from FIGS. 47, 48, and 49. In one exemplary process flow, the product can be disassembled. The disassembled product can be cut / shredded, which can then be subjected to a pretreatment process (e.g., thermolyzer process, heating, cooling, delamination, presorting, etc.) and sieved to remove plastics, carbon-based material, etc. The resultant mix can be subjected to rod milling to reduce the product to particles having the target average size. Separation can be done via wet jigging, magnetic separation, enhanced gravity separation, shaking table, etc. to separate out the targeted components from the mix.

[0094] EXAMPLES

[0095] The following examples include exemplary implementations and test results of embodiments disclosed herein.Atty. Ref. No. 0073605-000845

[0096] Embodiments of an apparatus and process for recycling metals from electronic waste (e.g. waste printed circuit boards (WPCBs), etc.) can be provided. In some embodiments, a rod mill was utilized followed by size classification to utilize the differences in the original size of the metals present in WPCB components and their malleability for the selective liberation of metals in various size fractions. The malleable base metals (such as, e.g., Cu and Al, etc.) which present in coarse size in WPCBs components (such as, e.g., circuitry and capacitors) are expected to liberate in their original coarse sizes, while the precious metals (used as, e.g., plating layers and contact materials) anbe d the brittle components (such as, e.g., Si present in ceramic components) are expected to liberated in fine size fractions (-0.595 mm).

[0097] Upon liberation, the coarse size fraction (e.g., +0.595 mm) can be subjected to gravity separators (such as, e.g., jig, etc.) for the separation of the dense metals (such as, e.g., Cu) from light metals (such as, e.g., Al). The liberated metals in medium and fine size fractions, (e.g., - 0.595+0.149 mm, and -0.149 mm, respectively), obtained from size classification of the rod mill product could be treated with appropriate physical separation units as well. For example, the medium fraction could be treated via at least one shaking table and / or via one or more spiral units, and the fine fraction could be treated by at least one enhanced gravity separation and / or at least one flotation separation device or flotation extraction device (e.g. flotation tank, etc.). Depending on the performance of these units and the target recovery and grade values, the product streams can be subjected to further liberation to enhance the recovery or grade.

[0098] Magnetic separation can also be subsequently used for all fractions to potentially remove ferrous metals and further concentrate the target metals (e.g., Al, Cu, Au, Ag, and Pd) in the non- ferrous fractions. The magnetic fraction could be also used before the specific gravity separation.

[0099] It was determined that electronic waste (or “e-waste”) can include waste printed circuit boards (WPCBs), which can encompass about 3% of nearly 45 Mt / year of global e-waste generation. WPCBs can include a number of metallic components, including base metals (Cu, Al) and precious metals (Au, Ag, Pd), with a concentration higher than those of primary resources. Embodiments of the apparatus and process of recovering metals from e-waste (e.g. WPCBs) can involve multiple stages, e.g., pretreatment / liberation, physical separation, and chemical separation.Atty. Ref. No. 0073605-000845

[0100] The majority of conventional methods focus on hydrometallurgical processing method for recycling which requires extensive chemicals and energy. Some other conventional methods using mechanical recycling use fine grinding to liberate followed by fine particle separation methods, which also requires significant energy metals that requires significant energy due to the high hardness and tenacity of WPCBs.

[0101] In contrast to conventional approaches, embodiments of the apparatus and process can help avoid the energy and time requirements for grinding of WPCBs to very fine sizes. Instead, a rod mill or other type of comminution mechanism can be utilized to take advantages of differences in the malleability of the WPCB components and liberate base metals in course fraction and other components in medium and fine size fractions. Embodiments can facilitate use of wide range of coarse, medium, and fine physical separation techniques including but not limited to the specific gravity separation to obtain high recovery of the elements with high purity.

[0102] Characterization and Liberation of Metals of Waste Printed Circuit Boards.

[0103] Materials and Methods.

[0104] Materials.

[0105] The shredded processed WPCBs to less than a nominal size of 6 cm was provided by industry. The WPCBs was expected to contain base, and precious group metals (PGMs), glass fiber, and carbon / char particulates from processing by the industry and further characterized for potential recovery of metals.

[0106] Characterization for Liberation Analysis.

[0107] The char-metal WPCBs was comprehensively characterized for size fractions, ash and elemental contents, and composition phases. From 105 kg of char-metal mixture, a 30 kg representative sample was taken for initial characterization and liberation studies. The sample was first subjected to size analysis (using dry screening for size fractions larger than 0.149 mm, and wet screening for the size fraction finer than 0.149 mm. Approximately 1 kg of the sample was screened into eight different size fractions, + 25.4 mm, - 25.4 + 12.7 mm, - 12.7 + 4.76 mm, - 4.76 + 1.19 mm, - 1.19 + 0.595 mm, - 0.595 + 0.297 mm, - 0.297 + 0.149 mm, - 0.149 mm. Representative samples of each size fraction were subsequently pulverized in the RETSCH ZM 200 for characterization. Proximate analysis was conducted using thermogravimetric (TGA) analysis. The elemental content of each size fraction was performed using Thermo FisherAtty. Ref. No. 0073605-000845 Scientific XSeries 2 Inductivity Couple Plasma-Mass Spectrometry (ICP-MS) with detection limits of pg / L. The samples were ashed at 750 ⁰C to remove the organic matter, then digested using hydrofluoric acid and aqua regia analysis, according to the ASTM D6357-11, prior to ICP- MS analysis. Triplicate samples were analyzed, and ICP-MS standard solutions with known concentration of elements were used for the quality control. XRD analysis was performed to determine the phase characterization of the samples using a Malvern Panalythical Empyrean X- ray powder diffraction (XRD) with Cu (K-α) radiation source and Jade® pattern processing software. Microscopic analyses of the various size fractions were performed using a Thermo Fisher Scientific Apreo 2 Scanning Electron Microscope (SEM) coupled with Oxford instruments energy-dispersive X-ray spectroscopy (EDS) detector for elemental mapping to validate the liberation results obtained from the elemental analysis of the ground and non-ground samples. Particle counting was used to evaluate the degree of liberation of metals (equation 1); therefore, metal-non-metal composites were treated as locked particles. ^^^^ ^^^^ ^^�× 100% (Eq. 1) where DL represents the degree of liberation, Nfreedenotes the number of free particles of the metal of interest, and Nlockedis the number of interlocked particles with either non-metal particles or other

[0109] The size-by-size density fractionation, shown in FIG. 2, was performed to provide a baseline for liberation analysis and comminution experiments. Upon size classification of the feedstock, a representative sample of each size fraction (except for -.149 mm) was obtained and subjected to a density fractionation (i.e., float-sink analysis) at specific gravity (SG) values of 1.8, 2.5 and 2.95 using lithium metatungstate (LMT) solution. The SG values for the solution were selected based on the density of heavy metals, light metals, and organic matter present in the sample. LMT is a heavy liquid with a SG of 2.95 and can be mixed with water to obtain lower SG values. In this process, each size fraction was submerged and mixed in a 2-L beaker containing LMT solution with the lowest SG, and enough time was provided for the materials to be segregated in the float and sink fractions. The float fraction was removed using a screening tool, allowing the drainage of the excess medium, and washed multiple times with DI water. TheAtty. Ref. No. 0073605-000845 remaining medium was then filtered to recover the particle that sank at the bottom of the beaker. The sink fraction was then rinsed and subjected to the next denser medium, and the process was repeated. As a result, each size fraction was separated into four density fractions, i.e., -1.8 SG, 1.8x2.5 SG, 2.5 x 2.95 SG, and +2.95 SG.

[0110] Table 1 shows the pictures of the density fractions obtained from each size class. Those vivid illustrations provide indirect evidence (e.g., color changes) for partial fractionation of the materials through size and density fractionation. For instance, the reddish-brown color of the +2.95 SG fraction might be an indicator of heavy-weight metal content such as copper, gold, and the like, while the silvery-white particles in the 2.5x2.95 SG could indicate the presence of light-weight metals such as aluminum. The dark color of the 1.8 SG float fraction could be attributed to the presence of carbon-rich (e.g., char) particles obtained from the processing of the plastic components in PCBs. The sized density fractionations were fully characterized to provide insights on how the target elements are liberated from the non-valuable elements. Table 1 - Size-by-size density fraction photos Size Fraction Specific Gravity Fractions (mm) +2.95 2.95x2.5 2.5x1.8 -1.8 -25.4+12.7-12.7+4.76 -4.76+1.19 -1.19+0.595Atty. Ref. No. 0073605-000845 -0.595+0.297 -0.297+0.149

[0111] Liberation Study.

[0112] Size reduction and grinding is the most energy extensive unit for processing primary and secondary sources. Efforts should be concentrated on minimizing the required energy for the liberation of valuable elements of interest. Various comminution experiments were performed including roller grinding, rod mill, and ball mill. Roller grinding reduced the size of the entire samples to below 1 mm. Although this approach liberated most components, it did not provide any selectivity for the liberation of metals into various size fractions. The mills, however, utilized the difference in malleability of different metals. Cu and Al are malleable and can be liberated from the other metals in coarse fraction, while the others such as Si (as an example) are brittle and liberated in fine size classes. Rod mills provide more uniform size distribution and generate less fine particles. Therefore, rod mill was selected for comminution and liberation of metals.

[0113] We investigated selective liberation of metals in PCBs in various size fractions utilizing the differences in their malleability by analyzing the milling time. This study facilitated understanding the metals liberations characteristics and identifying the optimum grinding time for the liberation of metals. This optimization results in effective metal liberation while minimizing the energy consumption and avoiding over-grinding of the materials, which causes reductions in recovery of elements in downstream physical and chemical processes.

[0114] For grinding time optimization, different (rod) milling times of 5 min, 10 min, 15 min, and 25 min were inve ee different sizes, +0.595 mm, -0.595 m .0.149 mm) were subjected to density f . RepresentativeAtty. Ref. No. 0073605-000845 samples from each si l content. The results from the analysis pro ted from the non- valuable elements aft s as the baseline for the liberation and perfor for the recovery of the target or valuable elements.

[0115] Results and Discussion.

[0116] Elemental Content.

[0117] FIG. 3 shows an exemplary schematic of a size-by-size density fractionation of comminution product process.

[0118] The elemental content of the char-metal mixture is reported on a whole-basis, representative sample of the feedstock. For the base metals content (Table 2), the results showed that the sample contains mostly Cu (19.5%), followed by Al (4.3%). Regarding the precious group metals (PGM), the sample contains approximately 32.2 ppm of Au, 10 ppm of Ag, and 3 ppm of Pd (Table 2). The concentration of the rest of PGMs (i.e., Rh, Ru, Pt, Re) were below 1 ppm. The major impurities in the sample were identified as Fe (3.7%), and Si (0.6%). Table 2 - Base metals, PGMs and major impurities content in char-metal mixture Base Metals Concentration Unit Cu 19.5 % Al 4.3 % ize -0.595+0.297 mm, -0.297+0.149 mm, and -0.149 mm. Each size fraction was then characterizedAtty. Ref. No. 0073605-000845 for ash and elemental contents, as well as composition phases. The size fractionation results shows that the majority of the sample, approximately 60%, is present in the fine fractions, below 1.19 mm (see FIG. 3). The higher ash content in the coarse fractions, + 1.19 mm, is the result of metals and ceramic content used for the PCBs’ base, which are mainly reported in coarse fractions. The carbon content is less than 10% in the coarse fractions (+1.19 mm), and about 10- 20% in the finer fractions. The carbon and volatile content could be associated with the char and plastic resins used in PCBs (Table 3). The removal of carbon content through physical separation could significantly increase the grades of the elements of interest.

[0121] FIG. 4 shows an exemplary size fractionation of char-metal mixture plot. Table 3 - Size fractions and proximate analysis Size Fraction Volatile Fixed Weight Cumulativ Cumulative (mm)Ash (%)e Carbon % (%) (%) % Passing (%) Retained +25.4 81.5 9.5 9.0 0.5 99.5 0.5 -25.4+12.7 88.3 7.0 4.7 4.2 95.3 4.7 -12.7+4.76 91.2 2.6 6.1 14.6 80.7 19.3 -4.76+1.19 84.8 5.7 9.5 22.5 58.2 41.8 -1.19+0.595 69.5 13.1 17.4 12.5 45.7 54.3 -0.595+0.297 71.9 10.3 17.8 8.5 37.2 62.8 -0.297+0.149 71.7 8.6 19.7 14.7 22.5 77.5 -0.149 77.2 8.7 14.1 22.5 0.0 100.0 Total 79.2 7.7 13.0 100.0

[0122] Size-By-Size Elemental Content And Distribution.

[0123] Elemental analysis of size fractions was conducted to evaluate the grade and distribution of base metals, PGMs, and major impurities in various size fractions. The data revealed that most (e.g., 60-80%) of the base metals (Cu, and Al), are reported in the coarse fractions (+1.19 mm). The concentration of Cu in the coarse fractions varies from approximately 20-30%, and it is less than 20% in the finer fractions (see FIG. 4). Al has higher concentrations in the fractions coarser than 0.149 mm, ranging from 4-6%, and its concentration decreases in the finer fractions, -0.149 mm, to less than 1% (see FIG. 4).

[0124] FIGS. 5A and 5B show exemplary size-by-size base metals content and distribution plots.Atty. Ref. No. 0073605-000845

[0125] The majority (i.e., 69%) of the Au presents in the fine fractions (-1.19 mm), out of which approximately 34% by weight with a concentration of about 50 ppm is reported in the finest size fraction (e.g., -0.149 mm) (see FIGS. 5A and 5B). Therefore, efforts should be concentrated on the recovery of base metals from coarse fractions, and the Au recovery from the fine fractions, upon liberation. Ag, Pd and the remaining Au are relatively equally distributed in all other fractions ranging from 5-12 ppm and 1-4 ppm, respectively (see FIGS. 5A and 5B).

[0126] FIGS. 6A and 6B show exemplary size-by-size PGM content and distribution plots.

[0127] The size-by-size analysis of Fe revealed that it follows the same trends as base metals. Major portions of this element are reported in the coarse fraction with more than 30% in the - 4.76 + 1.19 mm fraction (see FIGS. 6A and 6B). About 15% of Fe was also found present in the finest fraction (- 0.149 mm), as one of the major impurities for this fraction containing the majority of the Au.

[0128] Size-by-size Phase Characterization.

[0129] FIGS. 7A and 7B show exemplary size-by-size Fe content and distribution plots.

[0130] Characterization of size fractions showed that the coarse fractions, +1.19 mm, contain the majority of the base metals and impurities. In contrast, PGMs are relatively more distributed in the fine size fractions (below 1.19 mm), especially in the finest size fraction (i.e., -0.149 mm). The feedstock was further characterized for the phase composition of each size fraction through X-ray powder diffraction (XRD) analysis. The most significant peaks in the XRD patterns of each size fraction (see Table 4) were found to be Cu and Si, representing metal and non-metal contents, respectively. Table 4 - Size-by-size XRD patterns Size Fraction Size Fraction (mm)XRD(mm) XRD -25.4+12.7 +25.4Atty. Ref. No. 0073605-000845 -4.76+1.19 -12.7+4.76 -0.595+0.297 -1.19+0.595 -0.149 -0.297+0.149

[0131] FIG. 8 shows an exemplary size-by-size comparison of intensity of diffraction peaks.

[0132] The XRD results were found to be consistent with the elemental content analyzed by ICP-MS, and most of base metals were reported in size fractions coarser than +1.19 mm. The XRD patterns showed that the highest intensity diffraction peaks related to CuO occur in the four courser fractions, +25.4, -25.4+12.7, -12.7+4.76, -4.76+1.19 mm; therefore, verifying the ICP- MS elemental analysis results. The samples were ashed at 750 °C for 8h in a muffle furnace, to remove the organic matter prior to XRD. Although the ashing process might have caused the conversion of metals to their oxides, e.g., Cu to CuO.

[0133] Size-by-size density fractionation.

[0134] FIG. 9 shows an exemplary size-by-size density fractionation weight distribution plot.

[0135] The weight distribution results from the size-by-size density fractionation show that for most of the size fractions the majority of the sample is present in the 1.80 SG float and 2.50 x 1.80 SG, which indicates that most of the heavy metals are interlocked with light metals and non- metal particles (see FIG. 9). Base Metals Liberation.

[0136] FIGS 10A and 10B show exemplary Cu distribution and concentration in the sized density fractions plots.Atty. Ref. No. 0073605-000845

[0137] Based on the elemental content of the feedstock, Cu was found to be the primary element, encompassing 19% of the feedstock, and was mainly reported in coarse fractions larger than 1.19 mm. The distribution and concentration of this element as a function of size and density (see FIG. 10) showed its liberation from the other metals increases as the particle size decreases, resulting in reporting this element to the heaviest fraction (i.e., +2.95 SG). More than 75% of Cu is recovered in +2.95 SG fraction of size classes finer than 1.19 mm. The grade of the Cu in these fractions was more than 50%, which could be potentially further purified through traditional purification processes. Therefore, this element can be potentially concentrated using gravity separation in size fractions smaller than 1.19 mm, without any size-reduction. Upon recovery of this element, the remaining materials can be further liberated, as needed, for effective separation of other elements. However, its concentration from the coarser size fraction (i.e., + 1.19 mm) requires size reduction / liberation.

[0138] FIGS. 11A and 11B show exemplary Al distribution and concentration in the sized density fractions plots.

[0139] Al was the second dominant element (e.g., 4.3%). As shown in FIGS. 11A and 11B , Al was partially liberated in size fractions below 0.595 mm, as more than 60% of this element was reported in lower density fractions. Reporting this element to the density fraction of 1.8 x 2.5 SG, instead of 2.5 x 2.95 SG was attributed to partial liberation of this element, and its separation needs further liberation from the other components, mainly Si and char materials.

[0140] PGMs liberation.

[0141] FIGS. 12A, 12B, 12C, 12D, 12E, and 12F show exemplary PGMs distribution and concentration in the sized density fractions plots.

[0142] The distribution and concentration of Au in sized density fractions showed that, similar to Cu, the liberation of Au increases as the size decreases. More than 60% recovery and 90 ppm grade of Au was obtained in the +2.95 SG fraction of less than 0.595 mm size classes, showing the potential of using gravity separation for concentrating Au. The liberation of this element in coarser size fractions requires size reduction. The data presented in FIGS. 12A, 12B, 12C, 12D, 12E, and 12F revealed that Pd and Ag do not follow the same trend as Au; therefore, selective liberation could also be considered to further liberate Pd and Ag in the fine size fractions upon separation of Au.Atty. Ref. No. 0073605-000845

[0143] Major impurity liberation.

[0144] FIGS. 13A and 13B show exemplary Fe distribution and concentration in the sized density fractions plots. These FIGS. show the distribution and concentration of Fe as the major metal impurity in PCBs, which can be potentially removed from the samples by utilizing their magnetic susceptibility and density, respectively, from the base and PGMs. Fe did not follow the same trend as Cu and Au. No liberation was found for this element, and its separation from the concentrated products will require further liberation.

[0145] Microscopic, SEM-EDS and degree of liberation analyses.

[0146] FIG. 14 shows a microscopic view of the -25.4+12.7 mm size fraction. FIG. 15 shows a microscopic view of the -12.7+4.76 mm size fraction. FIG. 16 shows an SEM-EDS image and distribution maps for individual elements (base metals, Fe and Si) of -4.76+1.19 mm size fraction. FIG. 17 shows an SEM-EDS image and distribution maps for individual elements (base metals, Fe and Si) of -1.19+0.595 mm size fraction. FIG. 18 shows an SEM-EDS image and distribution maps for individual elements (base metals, Fe and Si) of -0.595+0.297 mm size fraction. FIG. 19 shows an SEM-EDS image and distribution maps for individual elements (base metals, Fe and Si) of -0.297+0.149 mm size fraction. FIG. 20 shows an SEM-EDS image and distribution maps for individual elements (base metals, Fe and Si) of -0.149 mm size fraction.

[0147] Microscopic analyses of the feedstock's size fractions were performed to validate the liberation results obtained from the elemental analysis of the sized density fractions and to perform the degree of liberation analysis. For this analysis, the size fractions coarser than 4.76 mm were analyzed by a microscope, and the finer size fractions were analyzed using SEM- coupled with EDS detector for elemental mapping. The images confirmed that, in general, more metal liberation is achieved with a decrease in particle sizes. FIGS. 14 and 15 show that the metals are not liberated from each other in coarse fractions, + 4.76 mm. FIGS. 16, 17, 18, 19, and 20 confirm that Cu is well-liberated in fractions smaller than 1.19 mm. Although other elements such as Al and Si follow the same trend as Cu, it is evident from the SEM images and EDS mapping results that they are not as well-liberated as Cu. The analysis of the -0.149 mm size fraction revealed that the majority of the elements in this fraction are well-liberated, providing an opportunity for physical separation of target metals using enhanced gravity separators or flotation processes.Atty. Ref. No. 0073605-000845

[0148] FIG. 21 shows a calculated Cu, Al, and total metals degree of liberation plot.

[0149] The degree of liberation confirmed that, in general, more metal liberation is achieved with a decrease in particle sizes. FIG. 21 shows that the metals are not liberated from each other in the coarse fractions, + 4.76 mm, in which Cu, Al, and total metals are liberated less than 12%, 8%, and 6%, respectively. However, Cu is more than 91% liberated in size fractions smaller than 1.19 mm. Although Al follows the same trend as Cu, it is evident from the degree of liberation results that it is not as well-liberated as Cu. Al reaches a degree of liberation of more than 88% at size fractions smaller than 0.595 mm.

[0150] Liberation optimization.

[0151] FIG. 22 exemplary weight distribution of size-by-size density fractionation of the rod mill product ground in four different milling time.

[0152] The size-by-size density fractionation weight distribution results from the liberation optimization show that for most of the size fractions the majority of the sample is present in the 2.95 SG sink and 2.5 x 2.95 SG, which indicates that most of the heavy metals are liberated from light metals and non-metal particles.

[0153] Base metals liberation after comminution.

[0154] FIGS. 23A, 23B, 23C, and 23D show plots for base metals distribution and concentration in the sized density fractions in four different milling time.

[0155] Based on the elemental content of the feedstock, Cu was found to be the primary element, encompassing 19% of the feedstock, and was mainly reported in coarse fractions larger than 1.19 mm. The distribution and concentration of this element as a function of comminution time, size, and density showed its liberation from the other metals increases as the milling time increases, resulting in reporting this element to the heaviest fraction (i.e., +2.95 SG). As shown in FIGS. 23A, 23B, 23C, and 23D, more than 95% of Cu is recovered in +2.95 SG fraction by 15- and 25-min milling time. The grade of the Cu in these fractions was more than 60%, which could be potentially further purified through traditional purification processes. Therefore, after 15 min. of milling, this element is liberated and can be potentially concentrated using gravity separation. Upon recovery of this element, the remaining materials can be further liberated, as needed, for effective separation of other elements. Al was liberated in size fractions above andAtty. Ref. No. 0073605-000845 below 0.595 mm after milling for 15 min., as more than 90% of this element was reported in lower density fraction, 2.5 x 2.95 S.G.

[0156] PGMs liberation after comminution.

[0157] FIGS. 24A, 24B, 24C, 24D, 24E, and 24F show plots for PGMs distribution and concentration in the sized density fractions in four different milling time.

[0158] The distribution and concentration of Au, Ag, and Pd in sized density fractions showed that, similar to base metals, the liberation of these elements increases as the milling time increases. More than 90% Au recovery in the +2.95 SG fraction was obtained in both size classes, e.g., larger, and finer than 0.595 mm after milling for 15 min, showing the potential of using gravity separation for concentrating Au. The data presented in revealed that Ag and Pd follow the same trend as Au; however, in size fraction larger 0.595 mm, Ag is partially liberated. Therefore, selective liberation could also be considered to further liberate Ag in the coarse size fractions upon separation of Au and Pd.

[0159] SEM-EDS and degree of liberation analysis.

[0160] FIG. 25 shows an SEM-EDS image and distribution maps for individual elements (Al, Si, and C) of -0.595 mm +0.149 mm size fraction and 2.95 float for milling time of 5 min. FIG. 26 shows an SEM-EDS image and distribution maps for individual elements (base metals, Si, and C) of -0.595 mm +0.149 mm size fraction and 2.95 sink for milling time of 5 min. FIG. 27 shows an SEM-EDS image and distribution maps for individual elements (Al, Si, and C) of - 0.595 mm +0.149 mm size fraction and 2.95 float for milling time of 10 min. FIG. 28 shows an SEM-EDS image and distribution maps for individual elements (base metals, Si, Fe, and C) of - 0.595 mm +0.149 mm size fraction and 2.95 sink for milling time of 10 min. FIG. 29 shows an SEM-EDS image and distribution maps for individual elements (Al, Si, and C) of -0.595 mm +0.149 mm size fraction and 2.95 float for milling time of 15 min. FIG. 30 shows an SEM-EDS image and distribution maps for individual elements (Cu) of -0.595 mm +0.149 mm size fraction and 2.95 sink for milling time of 15 min. FIG. 31 shows an SEM-EDS image and distribution maps for individual elements (Al, Si, and C) of -0.595 mm +0.149 mm size fraction and 2.95 float for milling time of 25 min.

[0161] The SEM-EDS results validate the liberation optimization results obtained from the elemental analysis of the sized density fractions in four different milling time and show thatAtty. Ref. No. 0073605-000845 more metal liberation is achieved in 15 min. FIGS. 25, 26, 27, and 28 confirm that, for 5min and 10 min, heavy metals, such as Fe, are not well-liberated from Al and other components, mainly Si and char materials. In contrast, FIGS. 29, 30, 31, and 32 confirm that, for 15 min and 25 min, heavy metals are well-liberated from Al, and Al is likewise liberated from Si and char materials.

[0162] FIG. 33 shows a plot of calculated Cu, Al, and total metals degree of liberation of comminution products.

[0163] The degree of liberation analysis confirmed that, in general, more metal liberation is achieved with a decrease in particle sizes and an increase in the milling time. FIG. 33 shows that Cu has a degree of liberation of more than 87% after 5 min of comminution; however, Al and total metals reach more than 80% degree of liberation only after 15 min of comminution for size fractions larger than 0.149 mm. The analysis of the -1.149 mm size fraction revealed that the majority of metals have a degree of liberation of more than 90% providing an opportunity for physical separation of target metals using enhanced gravity separators.

[0164] After a meticulous analysis of the size and density fractionations, results showed that, in general, the liberation of metallic and non-metallic elements is higher in finer particle size. The liberation study also revealed that some of the target elements such as Cu (encompassing 19% of the materials) and Au are well-liberated in size fractions smaller than 0.595 mm. Therefore, materials with size of less than 0.595 mm could be excluded from the size reduction for the metal liberation. Such exclusion results in reduction of feedstock of the grinding circuitry. Analysis of the liberation study identified the optimum grinding condition for the metal liberation in fraction of coarser than 0.595 mm. The optimum retention time of the materials for the rod mill was found to be 15 min, equivalent to 2 kg / h feed rate in the laboratory rod mill, for the liberation of the materials, at which more than 80% degree of liberation is obtained without overgrinding of the materials. This optimization, thereby, minimized the energy consumption during grinding and avoided over-grinding of the materials which cause recovery reduction of the elements in downstream physical and chemical processes.

[0165] Recovery of Base and Precious Group Metals from Waste Printed Circuit Boards by Physical Separation.

[0166] Materials and Methods.Atty. Ref. No. 0073605-000845

[0167] FIG. 34 shows an exemplary conceptualized liberation and physical separation processes to recover base metals and PGM from WPCBs.

[0168] The liberation analysis showed that material of size larger than 0.5 mm were not liberated, smaller than 0.5 mm were partially, and less than 0.149 mm were completely liberated. Therefore, materials with +0.5 mm particle size were subjected to a rod mill for liberation, followed by sizing for downstream physical separation. The char-metal mixture was sieved into three different size fractions, +0.595 mm, -0.595 mm +0.149 mm, and -0.149 mm. The partially liberated and completely liberated materials were directly subjected to several physical separation methods. However, the +0.5 mm materials were comminuted for 15 min (optimum rod mill griding time found in previous studies) for liberation of metals from non-metals and other metals and subsequently sieved into three different sizes +0.595 mm, -0.595 mm +0.149 mm, and -0.149 mm, which were subjected to multiple physical separation methods based on the particle size. FIG. 34 shows the schematic diagram of an exemplary metals liberation and conceptualized physical separation circuit which was tested to recover base and precious group metals from WPCBs.^ To investigate the potential of physical separation techniques to concentrate the target elements, gravity and magnetic separations were studied. These gravity separation units include^wet jigging, shaking table, and enhanced gravity separation (e.g., Multi Gravity Separator (MGS)) which were used to treat +0.595 mm, -0.595 mm, +0.149 mm, and - 0.149 mm size classes, respectively.^

[0169] Wet Jigging.

[0170] FIG. 35 shows an exemplary jigging operation principle schematic view and its products by layers.

[0171] The wet jig tests were used for treating the size fraction of + 0.595mm ground sample, and it was carried out using a pilot-scale jig, model Alljig Minijig from Allmineral. The jig contains a tank divided into two sections. In one section, an air pulsation mechanism drives the oscillatory water motion, and the other section contains a container, consisting of overlaying layers of Plexiglass which can be individually removed allowing the analysis of different vertical thevertical segregation of the materials based on their density, size, and shape. The operational conditions of the experiment were as follows: stroke frequency: 70 strokes per minute, jiggingAtty. Ref. No. 0073605-000845 time: 15 min, and bed expansion: 65 mm, remained constant during the test. FIG. 35 shows the jig, a schematic view of its operation principle, and illustrative pictures of the obtained jig products by layers. Magnetic separation was used to separate ferrous and non-ferrous fractions of each layer.

[0172] Shaking Table.

[0173] A conventional shaking table concentrator, Deister Model 15-S Laboratory Concentrating Table, was used to separate particles according to their size and density. The shaking table was used for treating the size fraction of -0.595 mm + 0.149 mm for ground and non-ground samples. The primary objective was to collect numerous splits of each sample throughout the table l of four splits (tailing – low density fine mate ddling 2 – dense fine materials, and concen s the table for each sample. A vibratory nto the table. The water flow rate and table in optimal” selection), and the collection of the ple across the table was achieved and the bed

[0174] Multi Gravit

[0175] FIG. 36 sho

[0176] Multi Gravity Separator (MGS), Gravity Mining Micro MGS, was used to selectively separate fine particles based on their density differences. The MGS works on a similar concept as a conventional shaking table. Since the table surface is placed inside a rotating drum, MGS achieves many times the normal gravitational pull on the particles as they move across the table in a film of water flowing along the interior surface of the drum. Utilizing the enhanced centrifugal field, finer particles can be separated more effectively than with conventional flowing-film separators. MGS was used for particles less than 0.149 mm. The operational conditions of the MGS tests were similar for both ground and not-ground samples. With the goal of obtaining maximum recovery, a feed rate of 10 Kg / hr., drum rotation of 290 RPM, wash water flowrate of 0.5 l / min, and a solid / liquid ratio of 15% by weight were used. Fig. 3 shows an illustrative picture of the MGS products.Atty. Ref. No. 0073605-000845

[0177] The char-metal mixture from the thermolyzer process, wet jig, shaking table, and MGS products were comprehensively characterized. Representative samples of the char-metal mixture and each physical separation product were pulverized in the RETSCH ZM 200 for elemental content performed using Thermo Fisher Scientific XSeries 2 Inductivity Couple Plasma-Mass Spectrometry (ICP-MS) with detection limits of pg / L. Prior to ICP-MS analysis the samples were digested using hydrofluoric acid and aqua regia, according to the ASTM D6357-11. Triplicate samples were analyzed, and ICP-MS standard solutions with known concentration of elements were used for the quality control. The metals recovery was defined by Eq. (2). ^^^^ ^^% ^^ ^^ ×�� ×× 100 (Eq. 2) where R represents the percent recovery of metals, CP and MP denote the concentration of products (%) and mass of products (%) respectively, and CF and MF are the concentration of feed (%) and mass of the feed respectively (%).

[0178] The elemental content of the char-metal mixture, on a whole-basis, is presented in Table 5. In terms of base metals, the results showed that the sample contains mostly Cu (16%), followed by Al (4.4%). For the PGMs, the sample contains about 31.4 ppm of Au, 11.3 ppm of Ag, and 1.6 ppm of Pd. The concentration of the remaining PGMs (i.e., Rh, Ru, Pt, Re) were below 1 ppm. Fe and Si were found to be the two main contaminants in the sample (3.9% and 0.7%, respectively). Table 5 - Base metals, PGMs and major impurities content in WPCB char-metal mixture Base Metals Concentration Unit Cu15.9%Al 4.4 % PGM Au31.4ppmAg 11.3 ppm Pd 1.6 ppm Impurity Fe 3.9 % Si 0.7 %Atty. Ref. No. 0073605-000845

[0179] Results and Discussion.

[0180] Wet Jigging.

[0181] FIG. 37 shows a plot for weight distribution of jig products.

[0182] After +0.595 mm materials were liberated using a rod mill, they classified into three different sizes, +0.595 mm, -0.595 mm +0.149 mm, and -0.149 mm by sieving, and the + 0.595 mm sample was subjected to wet jig separation followed by low intensity magnetic separation. FIG. 37 shows the weight distribution of the non-magnetic fractions of all layers obtained from jig separation unit. The data shows that most of the heavy materials, approximately 60% of the sample, are concentrated in the two bottom layers.

[0183] FIGS. 38A and 38B show 2base metals distribution and concentration in the jig products.

[0184] The jig results show that Cu with a grade of 91.6 % and recovery of more than 72% is present in the bottom layers (i.e., layers 1 and 2). FIGS. 38A and 38B shows that Al with a grade of 18.9% and recovery of 20% was reported in the tailing (layer 5); on the other hand, Cu grade and recovery decreased in the tailing to 13% and 1.5%, respectively. Layers 3 and 4 were considered as middling having Cu with grade 59.8% and recovery of more than 25% and Al with grade of 14% and recovery more than 56%.

[0185] Shaking Table.

[0186] FIG. 39 show a plot of weight distribution of shaking table products.

[0187] The shaking table was used to treat the ground and non-ground samples with size fraction of -0.595 mm +0.149 mm. The data shows the weight distribution of the non-ground and ground fractions of all products obtained from the shaking table. While most of the non- ground sample (77.8%) is reported in the tailing, most of the ground sample (50%) is reported in the concentrate.

[0188] FIGS. 40A, 40B, 40C, and 40D show plots for base metals distribution and concentration in the shaking table products.

[0189] Elemental analysis of the shaking table products was conducted to evaluate the grade and distribution of base metals, PGMs, and major impurities. The data in FIGS. 40A, 40b, 40C, and 40D revealed that most of the Cu is reported in the concentrate for both non-ground and ground sample with 69% and 87% grade and 60% and 87% distribution, respectively. InAtty. Ref. No. 0073605-000845 contrast, Al has a higher grade (more than 11%) and distribution (more than 50%) in the middling and tailing for both ground and non-ground samples, and its grade and distribution decrease in the concentrate to less than 6% and 31% for both ground and non-ground samples.

[0190] FIGS. 41A, 41B, 41C, 41D, 41E, and 41F show that Au is reported in the concentrate for both non-ground and ground samples with a concentration of about 416 ppm and 36 ppm and distribution of about 86% and 91%, respectively. Ag is relatively equally distributed in the non- ground sample with grade of about 272 ppm and distribution of about 38% in the concentrate (Figure 40). However, in the ground sample, Ag is mostly present in the concentrate with grade of 107 ppm and distribution of 90%. Similarly, Pd, in the concentrate for both non-ground and ground samples, has a grade of 6.8 ppm and 7 ppm and distribution of about 19% and 82%, respectively.

[0191] FIGS. 42A and 42B show plots of Fe distribution and concentration in the shaking table products.

[0192] FIGS. 42 A and 42B show the distribution and concentration of Fe as the major metal impurity in WPCBs. The results show that Fe is evenly distributed in all shaking table products meaning that no liberation was found for this element, and its separation from the target products will require further liberation and separation.

[0193] MGS.

[0194] FIG. 43 shows a plot for weight distribution of MGS products.

[0195] Multi Gravity Separator (MGS) was used to separate ground and non-ground samples based on the density of the particles. MGS was used for particles less than 0.149 mm. FIG. 43 shows the weight distribution of the non-ground and ground fractions of all products from the MGS. The majority, more than 70%, of both ground and non-ground samples is reported in the tailing.

[0196] FIGS. 44A, 44B, 44C, and 44D show plots for base metals distribution and concentration in the MGS products.

[0197] After the MGS experiments, the elemental analysis of the MGS products was performed to evaluate the concentration and distribution of target metals and major impurities. It is clear that most of the Cu is reported in the concentrate for both non-ground and ground samples with 9.6% and 16% grade and 98% and 99% distribution, respectively. Most of Al is also reported inAtty. Ref. No. 0073605-000845 the concentrate for both non-ground and ground samples with 8% and 8% grade and 99% and 97% distribution, respectively.

[0198] FIGS. 45A, 45B, 45C, 45D, 45E, and 45F show plots for PGMs distribution and concentration in the MGS products.

[0199] Most of Au is also present in the concentrate for both non-ground and ground samples with a grade of about 143 ppm and 87 ppm and distribution of about 68% and 67%, respectively. Ag and Pd follow the same trend as Au. Ag is mostly reported in the concentrate for both non- ground and ground samples with a grade of about 26 ppm and a distribution of more than 90% for both. Pd, in the concentrate for both non-ground and ground samples, has a grade of about 7 ppm and 6 ppm and a distribution of about 94% and 89%, respectively.

[0200] The results show that Fe is equally distributed in the tailing and concentrate proving that Fe is partially liberated, and its separation from the base metals and PGMs will require further separation.

[0201] FIGS. 46A and 46B show plots of Fe distribution and concentration in the MGS products.

[0202] Process Flow.

[0203] FIGS. 47, 48, and 49 show exemplary processes for different embodiments. It is proposed that shredded processed feedstock is first liberated. For liberation, shredding and / or milling (rod, hammer, and / or ring milling) could achieve complete dissociation of metals and non / metals; however, further grinding may be needed to fully liberate metals from WPCBs. From our previous study, it could be observed that WPCBs with particle sizes finer than 0.5 mm have more than 60% metal degree of liberation. Therefore, sieving the liberated particles first to decrease the energy consumption of the comminution circuitry by reducing the feed to the grinding circuitry (FIG. 48). The flowchart includes a promising combination of physical separation methods, e.g., gravity (wet jigging, shaking table, and MGS) and magnetic, to recycle base and precious metals from WPCBs. With the proposed flowsheet, 68% of Cu was successfully recovered with more than 59% grade in coarse fraction, i.e., + 0.595 mm, and 25% of Cu was recovered in the fine fraction, i.e., -0.595 mm, with PGMs making a total of 93% CuAtty. Ref. No. 0073605-000845 recovery. 70% of Au was recovered in the concentrate of shaking table and MGS with an average grade of 136 ppm. The results showed that Cu, Al, Au, Ag, and Pd with 45%, 10%, 102 ppm, 39 ppm, and 6 ppm grade and 93%, 61%, 70%, 72%, and 80% recovery, respectively, was successfully produced. The results can be even further improved with recycling loads and addition of cleaner and scavenger units. Depending on the type of materials and amount of liberated materials, all the materials (e.g., non-processed WPCB) could be directly subjected to milling (e.g., hammer or ring) following the dashed line in FIG. 48, followed by at least a size and a gravity separation unit (e.g., Jig, shaking table, enhanced gravity separation). This could be combined with other mechanical recycling methods (magnetic, electrostatic, flotation, etc.) or hydrometallurgical (e.g., FIG. 49, the staged leaching process including the first step being sulfuric acid leaching for base metal recovery, followed by thiurea leaching for Au, and Ag, and accompanied by hydrochloric acid for Pd leaching. The leachates are subjected to solvent extraction, precipitation, ion-exchange, etc) or the solid streams are sent to pyrometallurgical processes (e.g., smelting) to further treatment, purify, etc.

[0204] As another example, again, depending on the type of materials and degree of liberation, the materials (e.g., electronic waste, such as household or industrial e-waste, containing both malleable (e.g., Cu, Al, and PGM) and brittle (e.g., plastic components) could achieve a relatively high degree of liberation through specific types of shredding and / or combined with a milling process facilitating direct processing through gravity separation units (e.g., Jig, etc.) to separate plastic, Al, and mix of Cu, PGM and other high-density materials. This could be followed or preceded by other separation techniques such as magnetic, electrostatic, sorting, flotation, size classification, and or further liberation and mechanical recycling, combined with the downstream plastic processing, hydrometallurgical, and or pyrometallurgical processing for increased purity of the components and / or impurity removal.

[0205] As another example, the materials that cannot be processed by sorting or eddy current equipment (such as e-waste fraction smaller than about 5 mm size), could be subjected to this process flowsheet (e.g., a combination of shredding and milling (as needed for liberation), size separation, and gravity separation (e.g., Jig (wet, dry, two-stage), shaking table (wet, dry), enhanced gravity separation, Knelson, Falcon, etc.).

Claims

Atty. Ref. No. 0073605-000845 [00206] As another example, shredded solar panels could be subjected to size classification followed by a gravity separation to separate out the Al, and glass, and wafer (PV cells). Further milling and sizing and gravity separation, could be performed to further enhance the materials' purity. This could be combined with other physical separation and / or hydro and pyrometallurgical processes to purify the elements. [00207] It should be understood that the disclosure of a range of values is a disclosure of every numerical value within that range, including the end points. It should also be appreciated that some components, features, and / or configurations may be described in connection with only one particular embodiment, but these same components, features, and / or configurations can be applied or used with many other embodiments and should be considered applicable to the other embodiments, unless stated otherwise or unless such a component, feature, and / or configuration is technically impossible to use with the other embodiment. Thus, the components, features, and / or configurations of the various embodiments can be combined together in any manner and such combinations are expressly contemplated and disclosed by this statement. [00208] It will be apparent to those skilled in the art that numerous modifications and variations of the described examples and embodiments are possible considering the above teachings of the disclosure. The disclosed examples and embodiments are presented for purposes of illustration only. Other alternate embodiments may include some or all of the features disclosed herein. Therefore, it is the intent to cover all such modifications and alternate embodiments as may come within the true scope of this invention, which is to be given the full breadth thereof. [00209] It should be understood that modifications to the embodiments disclosed herein can be made to meet a particular set of design criteria. Therefore, while certain exemplary embodiments of the systems, compositions, materials, apparatuses, and methods of using and making the same disclosed herein have been discussed and illustrated, it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied and practiced within the scope of the following claims.Atty. Ref. No. 0073605-000845 (HPGR) and / or attrition milling the remaining components that are greater than the predetermined size.

7. The method of claim 1, wherein: the components include a malleable material and a brittle material.

8. The method of claim 1, wherein: separating additional components from the mix involves size separation, gravity separation, and / or magnetic separation.

9. The method of claim 1, further comprising: subjecting the separated out components to one or more material processing techniques to recover and / or purify the separated out components.

10. The method of claim 9, wherein: the one or more material processing techniques to recover and / or purify the separated out components includes a physical or physicochemical process, a hydrometallurgical process and / or a pyrometallurgical process .

11. The method of claim 1, wherein: the components include Cu, Al, Au, Ag, Pd, Rh, Ru, Pt, Re, Fe, lanthanides, Sc, Y, Ta, Li, Co, Ni, Mn, Si, plastics, and / or glass.

12. The method of claim 1, wherein: the product includes a printed circuit board, electronic waste, a consumer electronic, an industrial electronic, a solar panel, interconnect industry waste, a capacitator, plastic, automative scrap, glass, metal-scrap, municipal solid waste, incinerated ash, thermolyzer product, a catalytic converter, and / or a black mass.

13. A method for liberating material from a product, the method comprising: 37Atty. Ref. No. 0073605-000845 performing work on the product to generate a first mix comprising components of the product having particles that are, on average, a first predetermined size; separating a majority of the components from the first mix based on a density separation technique; comminution of the first mix to generate a second mix comprising components of the product having particles that are, on average, a second predetermined size; separating a majority of the components from the second mix based on a density separation technique; subjecting the remaining components of the first mix and / or the second mix to one or more comminution techniques, and separating additional components from the first mix and / or the second mix.

14. The method of claim 13, wherein: the first predetermined average size of the particles is about 0.5 to about 101.6 mm; and the second predetermined average size of the particles is about 0.150 mm to about 0.5 mm.

15. The method of claim 13, wherein: the one or more comminution techniques includes shredding, rod milling, roller grinding, ball milling, hammer milling, ring milling, impact milling, rotary drum milling, knife milling, jaw milling, rotor milling, cutter milling, chip milling, disc pulverizer, high-pressure grinding rolls (HPGR) and / or attrition milling.

16. The method of claim 13, wherein: subjecting the remaining components of the first mix and / or the second mix to one or more comminution techniques involves shredding, rod milling, roller grinding, ball milling, hammer milling, ring milling, impact milling, rotary drum milling, knife milling, jaw milling, rotor milling, cutter milling, chip milling, disc pulverizer, high-pressure grinding rolls (HPGR) and / or attrition milling the remaining components that are greater than the predetermined size. 38Atty. Ref. No. 0073605-000845 17. The method of claim 13, wherein: performing work on the product involves shredding, cutting, chopping, and / or mincing.

18. The method of claim 13, wherein: the components include a malleable material and a brittle material.

19. The method of claim 13, wherein: separating additional components from the first mix and / or the second mix involves size separation, gravity separation, and / or magnetic separation.

20. The method of claim 13, further comprising: subjecting the separated out components to one or more material processing techniques to recover and / or purify the separated out components.

21. The method of claim 1, further comprising: subjecting the product and / or components to a mechanical treatment, a heating treatment, thermal treatment, a thermolysis treatment, a pyrolysis treatment, a gasification treatment, a supercritical fluid depolymerization treatment, a liquid nitrogen treatment, and / or a delamination treatment.

22. The method of claim 13, further comprising: subjecting the product and / or components to a mechanical treatment, a heating treatment, thermal treatment, a thermolysis treatment, a pyrolysis treatment, a gasification treatment, a supercritical fluid depolymerization treatment, a liquid nitrogen treatment, and / or a delamination treatment. 39

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