Electrolytic extraction of elemental metals from metal compounds

Abstract

Disclosed are schemes for the recovery of elemental metals on an industrial scale without smelting, including, for example, recovery of near pure lead from recycled LABs by a specialized electrolytic treatment. Also disclosed are new processes, innovative electrolyzer designs and / or new uses of supplemental chemicals, which are necessary for successful electrolysis of pure metals from impure forms (e.g., pure lead from lead oxide), and which are particularly suitable for solid state electrolysis of mixtures containing lead pastes, electrolytes and supplemental chemicals. In particular, for recovery of near pure lead in LAB recycling processes, solid-state electrolysis of mixtures containing impure lead (e.g., lead paste) can be carried out by electrolytic treatments using supplemental chemicals, and can be scaled to industrial levels by using horizontal cathodes in the electrolyzer.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. utility patent application No. 17 / 737,869, filed on May 5, 2022, entitled “Electrolytic Extraction of Elemental Metals from Metallic Compounds” (Agency Case No. AGR2102US1U), the entire contents of which are incorporated herein by reference. Background Art

[0003] Gold, silver, copper, zinc and lead, among other elemental metals, can be recovered from materials containing these metals by various electrolytic processes such as electrolysis. For example, for the recycling of lead-acid batteries (LABs), the lead paste obtained therefrom (usually containing pure lead as well as fractions of lead monoxide, lead dioxide and lead sulfate) can be dissolved or mixed with an electrolyte and the resulting solution or mixture can then be electrolyzed at the cathode of an electrolysis apparatus to recover pure elemental lead (Pb).

[0004] However, despite the simplicity of concept and ease of implementation on a small scale, it has been impractical and completely unattainable to date to economically recover lead from battery paste on an industrial scale through an electrolytic process, with sufficient yield and purity, and in an environmentally friendly manner (as an alternative to existing methods that require high-temperature smelting). The electrode materials used to recover lead are relatively expensive, and the operating conditions of the electrodes tend to promote the formation of undesirable byproducts. In existing electrolytic methods, insoluble lead dioxide is often formed at the anode, limiting the flow of current and reducing operating efficiency. Similarly, the lead produced at the cathode using an acidic electrolyte will also be deposited as a thin film on the cathode surface, and this lead is difficult to remove from the cathode. If / when the current (i.e., the power source performing the electrolysis) is interrupted, this deposited lead will also dissolve back into the electrolyte. There are other disadvantages.

[0005] Therefore, there is a long-standing need in the art and industry for a scalable, cost-effective and environmentally friendly solution to extract and / or recover pure elemental metals from impure sources, such as recovering near-pure lead (Pb) from recycled LAB. Summary of the invention

[0006] Disclosed herein are systems, methods, processes and / or chemical compositions for recovering elemental metals on an industrial scale without smelting, for example, recovering near-pure lead from recycled LAB by specialized electrolytic processes. Several different embodiments disclosed herein feature new processes, innovative electrolyzer designs and / or new uses of supplementary chemicals that are necessary for the successful electrolysis of pure lead from impure forms, and are particularly suitable for solid-state electrolysis of a mixture comprising lead paste, electrolyte and the supplementary chemicals. In particular, for the recovery of near-pure lead in LAB recycling processes, solid-state electrolysis of a mixture comprising impure lead (e.g., lead paste) can be performed by using an electrolytic process using supplementary chemicals, and can be further scaled to industrial levels by using a horizontal cathode in the electrolyzer.

[0007] More specifically, various embodiments disclosed herein relate to an electrolysis system and method for recovering near-pure metal (e.g., elemental lead) from an impure metal material (e.g., lead oxide) containing a target metal (e.g., lead), the method comprising: combining the impure metal material with an electrolyte to form a slurry, the slurry being a mixture of the impure metal material and the electrolyte such that the electrolyte does not dissolve the target metal in the impure metal material; performing solid-state electrolysis on the slurry to form a target metal deposit and residual components; separating the target metal from substantially all of the electrolyte and at least some of the residual components; and melting the target metal deposit and removing dross such that the remaining molten target metal is near-pure without smelting. Several embodiments disclosed herein may also include one or more of the following: adding at least one supplemental chemical to the slurry prior to performing the solid-state electrolysis; mechanically separating the dross into component materials for additional processing; and / or desulfurizing the impure metal material prior to combining the impure metal material with the electrolyte to form the slurry. For certain such embodiments: the impure metal material includes a first impure form of the target metal and a second impure form of the target metal, the first impure form being chemically different from the second impure form; the impure metal material includes a third impure form of the target metal, the third impure form being chemically different from the first impure form and the second impure form; the target metal formed during solid-state electrolysis is extracted from the first impure form, the second impure form, and the third impure form; at least one supplemental chemical includes a first supplemental chemical, a second supplemental chemical, and a third supplemental chemical, wherein the first supplemental chemical enables solid-state electrolysis of the first impure form, the second supplemental chemical enables solid-state electrolysis of the second impure form, and the third supplemental chemical enables solid-state electrolysis of the third impure form; the target metal is elemental lead (Pb), wherein the first impure form is lead monoxide (PbO), wherein the second impure form is lead dioxide (PbO2), and wherein the third impure form is lead hydroxide (Pb(OH)2); and / or the electrolysis is performed using an electrolyzer including a horizontal cathode, and the slurry is placed on the horizontal cathode for electrolysis.

[0008] Several alternative embodiments disclosed herein relate to a system for recovering near-pure metal from an impure metal material containing a target metal, the system comprising at least one subsystem for: combining the impure metal material with an electrolyte to form a slurry, the slurry being a mixture of the impure metal material and the electrolyte such that the electrolyte does not dissolve the target metal in the impure metal material; performing solid-state electrolysis on the slurry to form a target metal deposit and residual components; mechanically separating the target metal from substantially all of the electrolyte and at least some of the residual components; and melting the target metal deposit and removing dross such that the remaining molten target metal is near-pure without the need for smelting. Certain embodiments may also include at least one subsystem for one or more of: adding at least one supplemental chemical to the slurry prior to performing the solid-state electrolysis; mechanically separating the dross into component materials for additional processing; and / or desulfurizing the impure metal material prior to combining the impure metal material with the electrolyte to form the slurry. For certain embodiments: the impure metal material comprises a first impure form of a target metal and a second impure form of the target metal, the first impure form being chemically different from the second impure form; the impure metal material comprises a third impure form of the target metal, the third impure form being chemically different from the first impure form and the second impure form; and / or the target metal is elemental lead (Pb), wherein the first impure form is lead monoxide (PbO), wherein the second impure form is lead dioxide (PbO2), and wherein the third impure form is lead hydroxide (Pb(OH)2).

[0009] Additional embodiments also relate to an apparatus for recovering near-pure lead from impure lead paste containing one or more of lead monoxide (PbO), lead dioxide (PbO2) or lead hydroxide (Pb(OH)2), the apparatus comprising: a mixer for combining the impure lead paste with an electrolyte to form a slurry, the slurry being a mixture of the impure lead paste and the electrolyte such that the electrolyte does not dissolve the lead monoxide (PbO), lead dioxide (PbO2) or lead hydroxide (Pb(OH)2) in the lead paste; an electrolyzer for performing solid-state electrolysis on the slurry to form spongy lead and residual components, and when the solid-state electrolysis is completed, a portion of the electrolyte can be discharged from the residual components; a converter, including a press, for mechanically separating the spongy lead from substantially all of the remaining electrolyte and producing lead bricks; and a melter for melting the lead bricks into molten lead and scum, wherein only near-pure lead remains after the scum is removed. Certain such embodiments may also include a desulfurization agent for converting any lead sulfate (PbSO4) in the lead paste to lead hydroxide (Pb(OH)2) prior to the mixer forming the slurry. For selected embodiments, the mixer may also be capable of incorporating at least one supplemental chemical into the slurry.

[0010] This summary is provided to introduce selected concepts in a simplified form that will be further described in the following detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to limit the scope of the claimed subject matter, nor is it an admission that any information provided herein is prior art to the embodiments described herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The foregoing summary and the following detailed description of illustrative embodiments will be more readily understood when read in conjunction with the accompanying drawings. For purposes of illustrating the embodiments, example configurations of the embodiments are shown in the accompanying drawings; however, the embodiments are not limited to the specific methods and mechanisms disclosed. In the drawings:

[0012] Figure 1A is a modified block diagram illustrating the major components of an exemplary end-to-end electrochemical system for recovering near-pure lead from LABs representing various embodiments disclosed herein and indicating the directional flow of materials between its various subsystems;

[0013] Figure 1B is a diagram showing the use of various embodiments disclosed herein Figure 1A A flowchart of an exemplary method for LAB recycling using a system;

[0014] Figure 1C yes Figure 1B a modified process flow chart of the illustrated process to further detail the separate processing of other recyclables and scum processing representative of various embodiments disclosed herein;

[0015] Figure 2A is an illustration providing a perspective view of an electrolyzer cell 100 representative of various embodiments disclosed herein;

[0016] Figure 2B It is provided to represent various embodiments disclosed herein Figure 2A An illustration of an exploded perspective view of the anode and interior of an electrolyzer cell in FIG.

[0017] Figure 3A Provides various embodiments representative of the present invention Figure 2A and Figure 2B an illustration of a cross-sectional side view of an electrolyser cell of , wherein the electrolyser cell is in an initial, ready-to-use configuration for performing electrolysis;

[0018] Figure 3B Provides various embodiments representative of the present invention Figure 2A and Figure 2B an illustration of a cross-sectional side view of an electrolyser cell of , wherein the electrolyser cell is filled with electrolytic material for electrolysis;

[0019] Figure 3C Provides various embodiments representative of the present invention Figure 2A and Figure 2B an illustration of a cross-sectional side view of an electrolyser cell of FIG. 1 , wherein electrolysis has been performed in the electrolyser cell and liquid components have been discharged from the electrolysis compartment;

[0020] Figure 3D It is provided to represent various embodiments disclosed herein Figure 2A and Figure 2B an illustration of a cutaway side view of an electrolyser cell of wherein the end product of electrolysis has been scraped off the horizontal cathode surface and removed from the electrolysis compartment;

[0021] Figure 4A is an illustration providing a perspective view of a vertical stack of electrolyzer cells representing various embodiments disclosed herein;

[0022] Figure 4B is an illustration providing a perspective view of a transverse production line including a plurality of electrolyzer cell stacks representative of various embodiments disclosed herein;

[0023] Figure 4C is an illustration providing a perspective view of a parallel array of a plurality of transverse production lines representing various embodiments disclosed herein, each transverse production line comprising a plurality of electrolyzer cell stacks;

[0024] Figure 5A is an annotated chemical representation of the molecular structures of each of lead monoxide (PbO), lead dioxide (PbO2), and lead hydroxide (Pb(OH)2) (collectively referred to as "lead oxide components" or "lead oxide");

[0025] Figure 5B is an annotated chemical representation of the respective molecular structures of lead sulfate (PbSO4) shown with and without bond charges for clarity (i.e., the lead (Pb) atom is paired with two oxygen atoms that are single-bonded to the sulfur atom);

[0026] Figure 6 is a block diagram of an example computing environment that can be used in conjunction with any of the various embodiments and aspects disclosed herein. DETAILED DESCRIPTION

[0027] Although various embodiments disclosed herein may be described as specifically directed to the recovery of elemental lead from recycled LAB, such embodiments may be equally applicable to the recovery of other metals and / or other metal sources. Therefore, it is not intended herein to limit such embodiments to lead or LAB recycling, but rather, the disclosure herein should be construed as broadly as applicable to a variety of different metals extracted or recovered from a variety of potential different sources.

[0028] Disclosed herein are systems, methods, and chemical compositions for recovering elemental metals on an industrial scale without smelting, particularly recovering elemental lead from recycled LAB by electrolytic processing. Although various embodiments disclosed herein may be described as specifically relating to the recovery of elemental lead from recycled LAB, these embodiments may be equally applicable to the recovery of other metals and / or other metal sources. Therefore, it is not intended herein to limit such embodiments to lead or LAB recycling, but rather, the disclosure herein should be understood as broadly as applicable to a variety of different metals extracted or recovered from a variety of potential different sources.

[0029] Understanding the various concepts contributes to a broader and more comprehensive understanding of the various embodiments disclosed herein, and those skilled in the art will readily appreciate the impact of these various concepts on the breadth and depth of the various embodiments disclosed herein. Certain terms used herein may also be used interchangeably with other terms used herein, and unless otherwise expressly stated, these terms should be interpreted as broadly as possible. For example, the terms electrolysis, electrowinning, and electrorefining used herein should be considered interchangeable terms such that when one term is used, the other terms are also implied therein, and therefore, unless expressly distinguished, any use of the term electrolysis should be understood to also include electrowinning and electrorefining. On the other hand, the term "electrolytic process" is explicitly intended to include and encompass electrolysis, electrowinning, and electrorefining.

[0030] In addition, those skilled in the art will readily recognize and fully appreciate that substances that typically use subscript numerals to represent their chemical composition (e.g., gaseous oxygen (O2), water (H2O), etc.) may be represented herein using conventional numerals instead of subscript numerals (i.e., gaseous oxygen is represented by O2, water is represented by H2O, etc.), which is the same and equivalent to the use of subscript numerals, and there is no difference between the use of conventional numerals and the use of subscript numerals anywhere in this document.

[0031] Electrolysis process

[0032] Electrolysis is a technique that uses direct current (DC) to drive non-spontaneous chemical reactions, which is well known and familiar to those skilled in the art. Using an electrolytic cell, electrolysis can be used to separate elements from one another. More specifically, during electrolysis, an electric current (specifically direct current (DC)) is passed through an electrolyte, causing a chemical reaction at the electrodes and decomposing the materials in the electrolyte.

[0033] The main components required to achieve electrolysis are electrolytes, electrodes, and an external power source. An electrolyte is a chemical substance that contains free and mobile ions and can conduct an electric current. The electrolyte can be an ion-conducting polymer, a solution, or an ionic liquid compound. For example, a liquid electrolyte can be produced by "salvation," i.e., by the attraction or association of ions of a solute with a solvent (e.g., water), producing mobile ion clusters and solvent molecules.

[0034] To achieve electrolysis, electrodes (properly connected to a power source) are immersed in an electrolyte but kept far enough apart from each other for current to flow between them through the electrolyte, which completes the circuit. In this configuration, the direct current provided by the power source attracts ions to their respective oppositely charged electrodes and drives a non-spontaneous reaction.

[0035] Each electrode attracts ions of opposite charge: positively charged ions ("cations") move toward the negatively charged cathode, which donates electrons, while negatively charged ions ("anions") move toward the positively charged anode, which extracts electrons. In practice, electrons are introduced at the cathode (as a reactant) and removed at the anode (as a desired end product). The loss of electrons is called oxidation, while the gain of electrons is called reduction.

[0036] The cathode can be made of the same material as the anode, but is usually made of a more reactive material because oxidation at the anode causes greater wear on the anode. The anode can be made of the same material as the cathode; however, the anode is usually made of a less reactive material than the cathode because wear on the anode is usually greater than wear on the cathode during electrolysis due to oxidation occurring at the anode.

[0037] When neutral atoms or molecules gain or lose electrons, such as those that might be on the surface of an electrode, they become ions and can dissolve in the electrolyte and react with other ions. Conversely, when ions gain or lose electrons and become neutral, they may form compounds that are separate from the electrolyte. For example, positive metal ions might deposit in a layer on the cathode. Furthermore, when ions gain or lose electrons without becoming neutral, their electronic charge still changes in the process.

[0038] The key process of electrolysis is the exchange of atoms and ions by the addition or removal of electrons produced by an applied direct current, thereby producing a desired end product (or multiple end products, as the case may be). The desired end product of electrolysis is usually in a different physical state from the electrolyte and can be removed by one of several different physical processes, for example, by collecting the gaseous end product from above the electrodes, by electrodepositing dissolved end products from the electrolyte, or by removing solid end product deposits on one of the electrodes (e.g., by scraping).

[0039] The decomposition potential of the electrolyte is the voltage required for electrolysis to occur, while the amount of the final product derived from the electrolysis is proportional to the applied current. According to Faraday's law of electrolysis, when two or more electrolytic cells are connected in series to the same power supply, the final products produced in the electrolytic cells are proportional to their equivalents.

[0040] Solid-state electrolysis

[0041] For "solid-state electrolysis", a solid metal compound or mixture of metal compounds ("active material") can be reduced electrolytically to a pure metal end product by contacting the active material directly with the cathode of an electrolytic cell. However, placing the active material on the cathode surface (e.g., "pasting") can be problematic because various active materials are not naturally sticky.

[0042] Typically, the active material is slurried directly onto the cathode by removing the cathode from the electrolyte in the electrolytic cell and then applying a mixture of the active material and electrolyte onto the cathode surface. After the mixture is dried on the cathode, the cathode is then suspended in the electrolyte of the electrolytic cell. However, in industrial-scale operations, slurrying the active material onto the cathode surface is time-consuming and expensive, in part due to the electrode size required for such slurrying. In addition, during the electrolysis process, the dried slurried active material on the cathode may absorb moisture from the electrolyte in the electrolytic cell, causing the slurried material to fall off or slide off the cathode, which may also cause such absorbed moisture to undergo aqueous electrolysis, both of which together effectively displace and / or prevent the desired electrolytic reaction of the active material. In addition, lesser end products may naturally accumulate and adhere to the cathode itself, and removing such end products from the cathode may be time-consuming, inefficient, and costly.

[0043] It is because of these inherent disadvantages that solid-state electrolysis has not been used commercially on an industrial scale to process active materials, with industries instead opting for more traditional methods of purifying active materials into desired end products, such as smelting. However, as is well known and widely understood by those skilled in the art, smelting has its own disadvantages, and there remains a need for an alternative purification process and machinery for performing the process on an industrial scale.

[0044] Recycling of lead-acid batteries

[0045] Lead-acid batteries (LAB) are widely used today and, unlike other types of batteries, are almost completely recyclable, making them the most recycled item today. Recycling lead is of great economic importance because LAB production is increasing year by year worldwide, but producing new lead is becoming increasingly difficult due to the depletion of lead-rich ore deposits. However, almost all current industrial-scale recovery of lead from LAB is based on smelting, a pyrometallurgical process in which lead, lead oxides (e.g., PbO and PbO2), and other lead compounds are heated to approximately 1600°F to 2200°F (900°C to 1200°C) and then mixed with various reducing agents to remove oxygen, sulfates, and other non-lead materials.

[0046] Unfortunately, lead smelting is highly polluting, producing large amounts of air waste (e.g., lead dust, arsenic, carbon dioxide, and sulfur dioxide), solid waste (e.g., slag containing hazardous compounds of lead and other heavy metals), and liquid waste (e.g., sulfuric acid, arsenic, and other heavy metals and their oxides). In fact, pollution from smelting is so high that the United States and other Western countries have had to shut down many smelters to protect the environment. While the relocation and expansion of smelting to less regulated countries has led to large-scale pollution and high levels of human lead contamination in those countries, similar restrictions can be expected over time as new technologies emerge.

[0047] Although various methods for recovering lead from LAB are known in the art, they all have one or more disadvantages that make them impractical. Therefore, there remains a need for improved apparatus and methods for scalable, non-smelting recovery of LAB to achieve maximum lead recovery with minimal environmental impact and not excessive cost. Although some efforts have been made to avoid smelting operations and use more environmentally friendly solutions, all methods have failed to date for a variety of reasons, ranging from different contamination issues to low yields and low profit margins to laboratory-based solutions that cannot be scaled up effectively or efficiently.

[0048] Electrolysis process

[0049] As briefly described above, gold, silver, copper, zinc and lead, among other elemental metals, may be recovered from materials containing these metals by various electrolytic processes such as electrolysis. For example, for the recycling of lead-acid batteries (LABs), the lead paste obtained therefrom (typically comprising pure lead as well as portions of lead monoxide, lead dioxide and lead sulfate) may be dissolved or mixed with an electrolyte and the resulting solution or mixture may then be electrolyzed at the cathode of an electrolysis apparatus to recover pure elemental lead (Pb).

[0050] However, despite the simplicity of concept and ease of implementation on a small scale, it has been impractical and completely unattainable to date to economically recover lead from battery paste on an industrial scale through an electrolytic process, with sufficient yield and purity, and in an environmentally friendly manner (as an alternative to existing methods that require high-temperature smelting). The electrode materials used to recover lead are relatively expensive, and the operating conditions of the electrodes tend to promote the formation of undesirable byproducts. In existing electrolytic methods, insoluble lead dioxide is often formed at the anode, limiting the flow of current and reducing operating efficiency. Similarly, the lead produced at the cathode using an acidic electrolyte will also be deposited as a thin film on the cathode surface, and this lead is difficult to remove from the cathode. If / when the current (i.e., the power source performing the electrolysis) is interrupted, this deposited lead will also dissolve back into the electrolyte. There are other disadvantages.

[0051] Therefore, there has long been a need in the art and industry for a scalable, cost-effective, and environmentally friendly solution to extract and / or recover pure elemental metals from impure sources, such as recovering near-pure lead (Pb) in the process of recycling LAB.

[0052] As used herein (including before and after), the term "nearly pure" shall refer to a purity within 90% of the average purity obtainable by conventional smelting processes. Similarly, the term "pure" shall refer to a purity equal to or exceeding the typical purity level obtainable by conventional smelting processes, while the term "complete purity" shall refer to a purity consisting of 99.000% elemental metal, without regard to natural surface oxidation or hydrogen oxidation. Therefore, for all embodiments disclosed herein for obtaining "nearly pure" metals, such disclosure should be deemed to also disclose alternative embodiments for obtaining "pure" and "completely pure" metals. Similarly, as used herein, the term "recovery" and other equivalent terms (e.g., purification, derivatization, etc.) shall refer to obtaining a purer metal (e.g., elemental lead) from a less pure form of the metal (e.g., lead oxide) by electrolysis or other electrolytic processes.

[0053] Figure 1A is a modified block diagram 10 showing the major components of an exemplary end-to-end electrochemical system for recovering near-pure lead from LABs representative of various embodiments disclosed herein and indicating the directional flow of materials between its various subsystems.

[0054] exist Figure 1A, LAB designated for recycling may be provided by a LAB source 12 (shown using dashed lines to indicate input or output to the system) to a LAB crusher 14, where the LAB may be physically broken down and separated into five major components: battery acid (when present), plastics, metallic substances, separators, and lead paste. The battery acid (typically sulfuric acid (H2SO4)) may then be output to an acid neutralizer 16 for further processing, although this operation may not be necessary (and therefore optional) when the battery acid has been removed or the acid is not present in the LAB provided by the LAB source 12. The LAB crusher may also include a plastic cleaner 40 for removing lead residues (typically lead monoxide) adhering to the surface of the plastic before outputting the lead-free (or nearly lead-free) plastic to the plastic recycler 18.

[0055] The metal material separated by the LAB crusher 14 can be sent to the metal material reclaimer 20 to recover its lead component (usually pure lead (Pb)) and transfer the recovered lead to the melter 32 (described below), while the remaining non-lead metal material is appropriately output (e.g., disposed of or further recycled). Similarly, the separator separated by the LAB crusher 14 can be sent to the separator cleaner 22 to recover the residual lead therefrom, and the residual lead is sent to the lead paste desulfurizer 24 together with the lead paste obtained by crushing the LAB by the LAB crusher 14 (directly and / or from the plastic cleaner 40), and the remaining non-lead separator components are output to the separator reclaimer 46.

[0056] The lead received directly by the pastel desulfurizer 24 from the crushed LAB in the LAB crusher 14, its plastic cleaner 40 and / or the partition cleaner 22 generally includes elemental lead (Pb), lead monoxide (PbO) and lead dioxide (PbO2) and lead sulfate (PbSO4). The pastel desulfurizer 24 processes the pastel to remove sulfur from the lead sulfate (PbSO4), which is a highly destructive environmental pollutant. The desulfurization can be achieved by introducing sodium hydroxide (NaOH) into the pastel to chemically convert the lead sulfate (PbSO4) into lead hydroxide (Pb(OH)2) and chemically converting the sodium hydroxide (NaOH) into sodium sulfate (Na2SO4), and then removing the sodium sulfate (Na2SO4) from the paste by the pastel desulfurizer 24 using any of a variety of methods known and understood by those skilled in the art. Additionally, barium sulfate (BaSO4) may also be added to the pastel as an additive prior to or during the desulfurization process, wherein the barium sulfate does not react with the sodium hydroxide (NaOH) during the desulfurization process and is intentionally retained in the resulting (and otherwise "desulfurized") pastel for subsequent removal by a subsequent subsystem. Thus, the desulfurization performed by the pastel desulfurizer 24 is intended to remove sulfur only from the lead sulfate (PbSO4). Regardless, the desulfurized pastel (now containing only metallic lead in the form of elemental lead (Pb), lead monoxide (PbO), lead dioxide (PbO2), and lead hydroxide (Pb(OH)2)) may then be conveyed to a slurry mixer 26, wherein the desulfurized pastel is combined with an electrolyte 42 and a supplemental chemical 44 (discussed in detail below) to form a lead slurry solution or mixture.

[0057] It is noted that for certain alternative embodiments of the system 10, the plastic, metal material, separator and lead paste may be provided directly and / or separately to the system 10 in an already crushed form via one or more input sources (not shown) in place of the LAB source 12, in which case such input may bypass the LAB crusher 14 and continue to the appropriate other subsystems accordingly. Likewise, for certain other alternative embodiments, the lead paste may also be provided directly to the system, that is, to the lead paste desulfurizer 24 if it has not yet been desulfurized, or to the slurry mixer 26 if it has been desulfurized (specifically for lead sulfate (PbSO4), rather than for barium sulfate (BaSO4), as described above).

[0058] At the slurry mixer 26, for several such embodiments disclosed herein, sodium hydroxide (NaOH) may also be used as an electrolyte for subsequent electrolytic treatment (e.g., electrolysis) of the lead paste, in which case the resulting lead slurry will be a mixture of desulfurized lead paste and electrolyte (rather than a solution thereof in a chemical sense). The lead slurry is then transferred from the slurry mixer 26 to the electrolyzer 28 for electrolytic treatment (described in more detail below). The electrolyzer 28 operates to produce substantially deoxidized elemental lead (Pb) from lead monoxide (PbO), lead dioxide (PbO2), and lead hydroxide (Pb(OH)2) in the lead slurry.

[0059] For certain other alternative embodiments of the system 10, rather than desulfurizing the impure metallic material prior to combining the impure metallic material with the electrolyte to form a slurry, the sulfur-containing impure metallic material may be combined with the electrolyte to form a sulfur-containing slurry, and the electrolyzer itself may be utilized to desulfurize the impure metallic material prior to or during such electrolysis. For example, this additional functionality of the electrolyzer may be accomplished by consuming the stoichiometric caustic contained in the electrolyte and generating sodium sulfate in situ, which may be separated from the resulting deoxidized lead in subsequent processing.

[0060] In any case, the resulting deoxidized lead can then be transferred to the converter 30 for conversion to a solid brick with a minimal amount of electrolyte and / or make-up chemicals. For a lead slurry mixture (rather than a solution), most of the electrolyte and / or make-up chemicals can be removed by the electrolyzer 28 prior to transfer to the converter 30, and / or the converter can include physical pressing of the deoxidized lead into a solid brick, which can also effectively remove most of the residual electrolyte and / or make-up chemicals. On the other hand, for a lead slurry solution, the converter 30 can precipitate the deoxidized lead, thereby separating it from the electrolyte and make-up chemicals before pressing into bricks.

[0061] The lead bricks (which may still contain small amounts of electrolyte, supplementary chemicals and other impurities, including but not limited to barium sulfate (BaSO4), lead oxides (lead monoxide, lead dioxide and / or lead hydroxide), and any new natural oxidation occurring on the surface of the bricks) are then sent to a melter / caster 32 for melting, descumming and casting into output ingots of nearly pure lead 48. The melting and casting may also include lead recovered by the metal material recoverer 20 described above as input. On the other hand, the scum may be sent to a mechanical separator 34 to separate elemental lead (Pb) and lead monoxide (PbO), which is then returned to the melter / caster 32 and the lead monoxide (PbO) is returned to the slurry mixer 26 and included in the next lead slurry mixture for subsequent processing. For selected embodiments, the barium sulfate (BaSO4), electrolyte and supplementary chemicals (and their residues) may be recovered and / or reused at various points in the system (not shown).

[0062] Figure 1B is a diagram showing the use of various embodiments disclosed herein Figure 1A Flow chart 60 of an exemplary method for LAB recycling in a system; Figure 1B In the embodiment of the present invention, at 62, the LAB received for recycling can be broken up to produce lead paste and other recyclables, which can be processed separately at 64, as described above with respect to Figure 1A Any additional lead recovered from this separate process may be returned and combined with the lead paste produced directly from the crushing at 62 .

[0063] At 66, the lead paste obtained at 62 (and 64, if any) may be desulfurized, such as by treatment with sodium hydroxide (NaOH), potassium hydroxide (KOH), ammonium hydroxide (NH4OH) or aqueous ammonia solution or other suitable chemicals, such that the resulting desulfurized lead paste substantially contains sulfur-free lead components, (e.g., Pb, PbO, PbO2, and Pb(OH)2), but does not contain lead sulfate (PbSO4). At 68, the desulfurized lead paste may be combined with electrolyte and supplemental chemicals to form a slurry mixture (or, in an alternative embodiment, a slurry solution). At 70, the slurry is then introduced into an electrolyzer cell, and at 72, solid-state electrolysis (or, in an alternative embodiment, a typical solution-based electrolysis) may be performed.

[0064] Once the electrolysis is complete, at 74, the liquid component may be drained first (which may include make-up chemicals or residues thereof), and at 76, the remaining solid component produced by the electrolysis may also be removed (which may be in the form of a "spongy lead" solid infiltrated with the residual liquid component), or in an alternative embodiment, both the liquid component and the solid component may be removed from the electrolyzer simultaneously. At 78, the "spongy lead" solid component (now comprising substantially pure lead (Pb)) may be pressed to remove substantially all of the remaining liquid component ("residue") and form substantially pure lead bricks. At 80, the lead bricks may then be melted to eliminate substantially all of the remaining trace non-lead components and other small impurities, the melting occurring (at temperatures far below those required for smelting) to further purify the lead bricks and form near-pure lead ingots for export.

[0065] It is important to note that while nothing herein limits the use of such embodiments to only lead recycling or to only that portion of the lead recycling process, Figure 1B Elements 70-76 in (represented in the figure as electrolytic process group 82) are performed using various embodiments of electrolytic cells described in more detail below; rather, other additional uses of such embodiments are also contemplated by such embodiments. For example, various embodiments disclosed herein can be used to further process the dross removed during melting 80, including but not limited to the above-mentioned Figure 1AProcessing described.

[0066] Figure 1C yes Figure 1B A modified process flow chart 60' of the process 60 is shown to further detail the separate processing of other recyclables 64 and scum processing 92 representative of various embodiments disclosed herein. Figure 1C In the embodiment of the present invention, at 84, the battery acid (usually sulfuric acid (H2SO4)) is neutralized and output from the system. At 86, the plastic is washed and output from the system, and any lead residues (usually lead monoxide) recovered from the surface of the plastic are combined with the lead paste to be desulfurized. Similarly, at 88, the separator is also washed and output from the system, and any lead residues (usually lead monoxide) recovered from the surface of the plastic are combined with the lead paste to be desulfurized. At 90, the metal material is washed (or "recovered"), the non-lead metal material is output (discarded or recycled), and its lead component (usually pure lead (Pb)) is directly conveyed to the melter and melted at 80. However, it should be noted that the metal material recovered from the LAB generally contains lead (Pb) and antimony (Sb) as an alloy, i.e., lead antimony (or antimony lead), where the lead and antimony do not need to be separated, so some alternative embodiments can output lead antimony from the reclaimer 90, melt at 80 and form nearly pure antimony lead instead of nearly pure elemental lead (Pb).

[0067] Figure 1C It is also shown how the dross produced by melting at 80 is mechanically separated at 92 and the lead monoxide (PbO) produced by the mechanical separation is added to a subsequent batch of desulfurized lead paste at 68 for reprocessing, while the elemental lead (Pb) produced by the mechanical separation is added back to a subsequent batch of spongy lead melted at 80.

[0068] Electrolyser cell with horizontal cathode

[0069] Disclosed herein is an electrolyzer cell comprising a horizontal cathode with a horizontal anode suspended above the horizontal cathode. The horizontal cathode may form the bottom of an electrolyzer compartment in which a mixture of active materials and electrolytes (e.g., in the form of a slurry) may be introduced, maintained, and processed. The horizontal anode may be suspended above the cathode in the upper portion of the electrolyzer compartment so that the anode may be physically engaged with the upper surface of the mixture of active materials and electrolytes held by the electrolyzer compartment, while the cathode may be naturally engaged with the bottom surface of the mixture of active materials held in the electrolyzer compartment. The anode may also include a small opening in the form of a vent, groove, hole, etc. (hereinafter referred to as a "vent") throughout the anode surface to allow gaseous oxygen (O2) and / or other gaseous substances produced by electrolysis to escape harmlessly (rather than being trapped below the anode and creating current resistance).

[0070] Thus, various embodiments disclosed herein may relate to and / or use an electrolyzer comprising a horizontal cathode located below a suspended anode for electrolyzing a mixture or solution containing a metal. For several such embodiments, the horizontal cathode may include a bottom surface of a compartment for housing a mixture or solution of a metal component, an electrolyte, and / or a supplemental chemical; a horizontal anode for engaging an upper surface of the mixture or solution in the compartment; a door corresponding to one side wall of the compartment to facilitate removal of a final product from the mixture or solution; and / or a removal mechanism to facilitate removal of the final product of the mixture or solution from the compartment (and the surface of the horizontal cathode) through the door. Certain embodiments disclosed herein are particularly directed to the use of recycling lead-acid batteries (LABs) without smelting, but it is not intended herein to limit the various embodiments to LAB recycling or lead recycling. Instead, the various embodiments disclosed herein may be applied to a variety of different electrolysis operations.

[0071] For these various embodiments, and in conjunction with the use of additional supplemental chemicals added to the slurry mixture of active material and electrolyte (discussed further below), a direct current can be passed through the mixture of active material and electrolyte from the cathode to the anode to produce a desired end product and cause the desired end product to settle on the surface of the cathode (for certain such embodiments, the end product may be a sponge of pure lead that retains some electrolyte and / or supplemental chemicals). More specifically, the direct current will effectively reduce the metal ions in the active material, separating them from their counterions - counterions such as oxygen ions and hydrogen ions, which in turn can form water (H2O) and gaseous oxygen (O2) - and cause the metal, now in its pure form, to be attracted and settle onto the horizontal cathode surface, partly due to gravity (metals are heavier than other components in the slurry) and partly due to natural ionic convection that occurs in the mixture during the electrolysis process.

[0072] Once the electrolysis is complete, and for several such embodiments disclosed herein, the electrolyzer compartment may also include an openable side to remove the electrolyte (including make-up chemicals and additional H2O produced during the electrolysis process) and the final product metal. Initially, the openable side may be only partially opened to first allow the pure liquid components (i.e., most of the remaining electrolyte, make-up chemicals, and additional water (H2O) produced during the electrolysis process) to leave the electrolyzer compartment, and for certain embodiments, to be directed away through a small diversion groove at the bottom of the openable side. In some embodiments, after the liquid components are discharged through the openable side of the electrolyzer compartment, the diversion groove can be moved to a storage location away from the openable side (e.g., to below the electrolyzer compartment).

[0073] After the liquid components have been drained (or, in alternative embodiments, without first draining the liquid components separately), the openable side can be fully opened to allow more solid components (i.e., the final product metal and any residual liquid components adhering thereto) to be physically removed from the electrolyzer compartment. For selected embodiments, the removal can be performed by a vertical scraping mechanism that extends across the width of the electrolyzer compartment and begins on opposite sides of the openable side, the scraping member physically contacting and gently scraping the entire cathode surface and adjacent sides of the electrolyzer compartment, but operating only below (and not physically contacting) the anode surface. In this manner, the scraping mechanism can be operated to push more solid components out of the electrolyzer compartment and into a collection container or onto a conveying mechanism (e.g., a conveyor belt) for further processing.

[0074] In this way, the various embodiments disclosed herein can overcome the shortcomings of the above-mentioned existing solid-state electrolysis methods as follows: (1) there is no need to dry-coat the active material to the cathode, thereby saving time and effort; (2) the accumulation of moisture absorbed by the dry-coated active material during the electrolysis process and interference with the production of the desired final product can be completely avoided; and / or (3) because the flat surface of the cathode is conducive to the scraping action (as described above), and the supplementary chemicals can help prevent the final product from solidifying or adhering to the cathode, the accumulation of the final product at the cathode will be easier to remove.

[0075] In addition, for various embodiments disclosed herein, multiple electrolyzer cells of the type described herein may be stacked vertically, with appropriate spacing between each electrolyzer cell, and these electrolyzer cells may share a single vertical drop space so that the final product can be pushed out of the multiple electrolyzer cells into a single collection container or a single conveying mechanism. In addition, several vertical stacks containing multiple electrolyzer cells may be arranged in a row and further share a single elongated collection container or a single elongated conveying mechanism. In addition, multiple rows of vertical stacks may be arranged and the final products produced may be combined together for further processing.

[0076] It is worth noting that, in addition to the disclosure herein, the applicant has discovered that achieving the electrolysis effects described herein depends on the use of certain specific chemicals mixed into the slurry together with the electrolyte and active materials. Although the present application does not involve the composition of any of these discovered chemicals, the various embodiments disclosed herein are in no way limited to the use of any specific chemical additives, whether confidential or proprietary (or the substance is widely used and well known).

[0077] Figure 2A is a diagram providing a perspective view of an electrolyzer cell 100 representative of various embodiments disclosed herein. Figure 2B It is provided to represent various embodiments disclosed herein Figure 2AFIG. 1 is an exploded perspective view of the anode 110 and the interior of the electrolyzer cell 100 in FIG. 1 . For convenience, Figure 2A and Figure 2B They are collectively referred to as Figure 2 in this article.

[0078] As shown in FIG2 , the electrolyzer cell 100 may include an anode 110 suspended above a horizontal cathode 120 at a distance suitable for conducting electrolysis. The electrolyzer cell 100 may also include a vertical containment surface 122 and at least one door 124 that together with the horizontal cathode 120 form and provide an electrolyzer compartment 126 in which a mixture of active material and electrolyte (e.g., in the form of a slurry) may be introduced, maintained, and processed. The vertical containment surface 122 and the door 124 (or at least their inner surfaces relative to the contents of the electrolyzer compartment 126) may be non-conductive.

[0079] As shown, anode 110 can be configured as a horizontal anode, but other forms of anodes can also be used, such as a series of anode rods, bars, grids or other structures that can be physically engaged with the upper surface of the electrolytic slurry placed on the cathode. In any case, anode 110 can be suspended above cathode 120 in the upper part of electrolyzer compartment 126, so that the anode can be physically engaged with the upper surface of the mixture of active materials and electrolytes held by the electrolyzer compartment, and the cathode can be naturally engaged with the bottom surface of the active material mixture held in the electrolyzer compartment. For those embodiments with horizontal anode features, anode 110 can also include small openings or vents 114 (i.e., "vents") throughout its surface to allow gaseous oxygen (O2) produced by electrolysis to escape harmlessly (rather than accumulating under the anode). The anode 110 may also include an opening 112 through which electrolytic slurry may be placed into the electrolyzer compartment and onto the horizontal cathode 120, with the amount of electrolytic slurry being sufficient to physically engage the upper surface of the electrolytic slurry with the suspended anode 110 simultaneously, thereby completing the circuit of current flowing between the cathode 120 and the anode 110 for electrolysis.

[0080] The electrolyzer cell 100 may also include a removal mechanism 160. For various embodiments, the removal mechanism 160 may include a vertically oriented surface extending across the width of the electrolyzer compartment 126 and originating on the side opposite the door 124 that is capable of physically contacting and gently scraping the entire cathode 120 surface and adjacent sides of the electrolyzer compartment 126 and operating below the anode 110 surface. The removal mechanism (or at least the portion thereof that is exposed to the contents of the electrolyzer compartment 126) may be non-conductive.

[0081] Figure 3A Provides various embodiments representative of the present invention Figure 2Aand Figure 2B FIG. 1 is a diagram of a cross-sectional side view of an electrolyser cell 100 of FIG. 1 , wherein the electrolyser cell 100 is in an initial, ready-to-use configuration for performing electrolysis. Figure 3A As shown, the electrolyzer compartment 126 is empty but ready to be filled, with the removal mechanism 160 in the set position and the door 124 closed. In this configuration, electrolytic slurry can then be placed in the electrolyzer compartment 126 and on the horizontal cathode 120 via the slurry line 144 extending through the opening 112 in the anode 110. Figure 3A Also shown is a conveyor belt 170 that includes a receiving side 172 and is disposed beneath the door 124 as a conveying mechanism for use in removing the contents of the electrolyzer compartment 126 after electrolysis is complete.

[0082] Figure 3B Provides various embodiments representative of the present invention Figure 2A and Figure 2B (as well as Figure 3A ) is a diagram of a cross-sectional side view of an electrolyzer cell 100 filled with electrolytic material 150 for electrolysis. Figure 3B As shown, the electrolytic material 150 includes a mixture of active material 130 and electrolyte 140 and supplementary chemicals dispersed therein. The bottom surface of the electrolytic material 150 is physically bonded (i.e., in physical contact) with the horizontal cathode 120, and the upper surface of the electrolytic material (specifically, its electrolyte component) is physically bonded with the anode 110 (for various embodiments, sufficient electrolyte can be included in the electrolytic material to form the upper surface of the electrolytic material to prevent solid material contact from forming between the cathode and the anode, which may cause an electrical short circuit and prevent the cathode plate from reducing the lead ions in the compound). Then, an electric current can be applied to the electrolytic material 150 through the anode 110 and the cathode 120, wherein the circuit is completed by the mobile ions in the electrolyte 140, and electrolysis occurs in the electrolytic material 150 accordingly.

[0083] Figure 3C Provides various embodiments representative of the present invention Figure 2A and Figure 2B (as well as Figure 3A and Figure 3B ), wherein electrolysis has been completed and liquid components 142 have been discharged from electrolysis compartment 126 by opening door 124 to a first position, which provides sufficient space for the liquid components to pass from electrolysis compartment 126 to conveyor belt 170 for recovery. At the same time, the desired end product 132 of electrolysis remains on horizontal cathode 120, awaiting removal from electrolysis compartment 126.

[0084] Figure 3DIt is provided to represent various embodiments disclosed herein Figure 2A and Figure 2B (as well as Figure 3A , Figure 3B and Figure 3C ) is an illustration of a cross-sectional side view of an electrolyzer cell 100 in which the final product 132 produced by electrolysis has been removed from the horizontal cathode 120 surface and the electrolysis compartment. Figure 3D As shown, the door 124 has moved to the second fully open position and the removal mechanism 160 has traversed the interior of the electrolyzer cell 100 and removed the final product 132 from the electrolyzer cell 100 and onto the conveyor belt 170. As shown, when the removal mechanism 160 is in this deployment position and the door 124 is fully open, the empty interior of the electrolyzer cell 128 is no longer the electrolysis compartment 126, but after the removal mechanism 160 returns to its original position and the door 124 is closed (e.g., as shown in FIG. Figure 3A ) will again become the electrolysis compartment 126. For convenience, Figure 3A , Figure 3B , Figure 3C and Figure 3D It may be collectively referred to herein as FIG. 3 .

[0085] Figure 4A is an illustration providing a perspective view of a vertical stack 102 of electrolyzer cells 100 representative of various embodiments disclosed herein. Figure 4A As shown, multiple electrolyzer cells 100 can be oriented vertically on a single conveyor 170 (further distinguished in the figure by thick moving arrows) to increase overall capacity, minimize floor space (or floor area) and increase utilization of conveyor 170 (and minimize expansion of conveyor 170).

[0086] Figure 4B is an illustration providing a perspective view of a transverse production line 104 including a stack 102 of a plurality of electrolyzer cells 100 representative of various embodiments disclosed herein. Figure 4B As shown, multiple stacks can be oriented linearly on a single conveyor 170 to further increase overall capacity while again increasing the utilization of the conveyor 170 (and minimizing the build-out of the conveyor 170), rather than requiring a separate conveyor for each stack 102. Additionally, for certain embodiments, multiple stacks 102 can be oriented on both sides of the conveyor 170 to form a dual production line (not shown).

[0087] Figure 4C is an illustration providing a perspective view of a parallel array 106 of a plurality of transverse production lines 104 representing various embodiments disclosed herein, each transverse production line 104 comprising a stack 102 of a plurality of electrolyzer cells 100. Figure 4CAs shown, multiple lateral production lines 104 and their corresponding conveyors can be arranged to form a three-dimensional array 106 of electrolyzer cells that feed a combined cross-conveyor 176. In addition, for certain embodiments, conveyors 170 from multiple production lines 104 can be oriented on both sides of the cross-conveyor 176 to form a dual array (not shown). Furthermore, the specific height, length, and width of such a parallel array 106 can be configured to best fit nearly any three-dimensional space, although alternative or additional conveyor configurations may be required.

[0088] Thus, various embodiments disclosed herein relate to electrolysis systems and methods for recovering near-pure metal (e.g., elemental lead) from an impure metal material (e.g., lead) containing a target metal (e.g., lead) (e.g., lead oxide or any other lead compound), the method comprising: combining the impure metal material with an electrolyte to form a slurry, the slurry being a mixture of the impure metal material and the electrolyte such that the electrolyte does not dissolve the target metal in the impure metal material; performing solid-state electrolysis on the slurry to form a target metal deposit and residual components; separating the target metal from substantially all of the electrolyte and at least some of the residual components; and melting the target metal deposit and removing dross such that the remaining molten target metal is near-pure without the need for smelting. Several embodiments disclosed herein may also include one or more of: adding at least one supplemental chemical to the slurry prior to performing the solid-state electrolysis; mechanically separating the dross into component materials for additional processing; and / or desulfurizing the impure metal material prior to combining the impure metal material with the electrolyte to form the slurry. For certain such embodiments: the impure metal material includes a first impure form of the target metal and a second impure form of the target metal, the first impure form being chemically different from the second impure form; the impure metal material includes a third impure form of the target metal, the third impure form being chemically different from the first impure form and the second impure form; the target metal formed during solid-state electrolysis is extracted from the first impure form, the second impure form, and the third impure form; at least one supplemental chemical includes a first supplemental chemical, a second supplemental chemical, and a third supplemental chemical, wherein the first supplemental chemical enables solid-state electrolysis of the first impure form, the second supplemental chemical enables solid-state electrolysis of the second impure form, and the third supplemental chemical enables solid-state electrolysis of the third impure form; the target metal is elemental lead (Pb), wherein the first impure form is lead monoxide (PbO), wherein the second impure form is lead dioxide (PbO2), and wherein the third impure form is lead hydroxide (Pb(OH)2); and / or the electrolysis is performed using an electrolyzer including a horizontal cathode, and the slurry is placed on the horizontal cathode for electrolysis. For selected alternative embodiments, the first, second and / or third impure forms may be any other lead compound other than an oxide.

[0089] Several alternative embodiments disclosed herein relate to a system for recovering near-pure metal from an impure metal material containing a target metal, the system comprising at least one subsystem for: combining the impure metal material with an electrolyte to form a slurry, the slurry being a mixture of the impure metal material and the electrolyte such that the electrolyte does not dissolve the target metal in the impure metal material; performing solid-state electrolysis on the slurry to form a target metal deposit and residual components; mechanically separating the target metal from substantially all of the electrolyte and at least some of the residual components; and melting the target metal deposit and removing dross such that the remaining molten target metal is near-pure without the need for smelting. Certain embodiments may also include at least one subsystem for one or more of: adding at least one supplemental chemical to the slurry prior to performing the solid-state electrolysis; mechanically separating the dross into component materials for additional processing; and / or desulfurizing the impure metal material prior to combining the impure metal material with the electrolyte to form the slurry. For certain embodiments: the impure metal material comprises a first impure form of the target metal and a second impure form of the target metal, the first impure form being chemically different from the second impure form; the impure metal material comprises a third impure form of the target metal, the third impure form being chemically different from the first impure form and the second impure form; and / or the target metal is elemental lead (Pb), wherein the first impure form is lead monoxide (PbO), wherein the second impure form is lead dioxide (PbO2), and wherein the third impure form is lead hydroxide (Pb(OH)2). Likewise, for selected alternative embodiments, the first, second and / or third impure forms may be any other lead compound other than oxides.

[0090] Additional embodiments also relate to an apparatus for recovering nearly pure lead from an impure lead paste containing one or more of lead monoxide (PbO), lead dioxide (PbO2), or lead hydroxide (Pb(OH)2) (or, for certain such embodiments, any other lead compound other than oxides), the apparatus comprising: a mixer for combining the impure lead paste with an electrolyte to form a slurry, the slurry being a mixture of the impure lead paste and the electrolyte such that the electrolyte does not dissolve the lead monoxide (PbO), lead dioxide (PbO2), or lead hydroxide (Pb(OH)2) (or, for certain such embodiments, any other lead compound other than oxides) in the lead paste; an electrolyzer for performing solid-state electrolysis on the slurry to form spongy lead and residual components, from which a portion of the electrolyte can be discharged when the solid-state electrolysis is complete; a converter, including a press, for mechanically separating the spongy lead from substantially all of the remaining electrolyte and producing lead bricks; and a melter for melting the lead bricks into molten lead and dross, wherein only nearly pure lead remains after the dross is removed. Certain such embodiments may also include a desulfurization agent for converting any lead sulfate (PbSO4) in the lead paste to lead hydroxide (Pb(OH)2) prior to the mixer forming the slurry. For selected embodiments, the mixer may also be capable of incorporating at least one supplemental chemical into the slurry.

[0091] With respect to all of the various embodiments disclosed herein, alternative embodiments are also contemplated in which the horizontal cathode is replaced with a horizontal anode, and the suspended anode is replaced with a suspended cathode. In addition, each step of the method performed by the various embodiments disclosed herein can be performed and controlled by a processing unit or other computing environment, including (but in no way limited to) the timing of each step of the operation, the coordination between different electrolyzer cells, slurry pipelines, conveyors, etc., and the change of time and charge used in the entire electrolysis process, as well as receiving and responding to feedback from resistors and other detectable events during the electrolysis process.

[0092] Electrolytes and Supplemental Chemicals

[0093] As disclosed above, sodium hydroxide (NaOH) and potassium hydroxide (KOH) etc. can be used as electrolytes for subsequent electrolytic treatment (e.g. electrolysis) of the lead paste, in which case the resulting lead slurry will be a mixture of desulfurized lead paste and electrolyte (rather than a solution thereof in a chemical sense). This method is different from the typical electrolytic treatment in which the lead paste is dissolved and suspended in an electrolyte solution. It should be noted that the typical electrolytic treatment does not require supplementary chemicals, while the electrolytic treatment of the mixture benefits from supplementary chemicals.

[0094] Figure 5AAn annotated chemical representation of the molecular structures of each of lead monoxide (PbO) 502, lead dioxide (PbO2) 504, and lead hydroxide (Pb(OH)2) 506 (collectively referred to as "lead oxide components" or "lead oxides"). Figure 5B is an annotated chemical representation of the respective molecular structures of lead sulfate (PbSO4), shown with bond charge 508a and without bond charge 508b for clarity (i.e., the lead (Pb) atom is paired with two oxygen atoms, which are single-bonded to the sulfur atom). As previously mentioned, the lead paste obtained from LAB during recycling usually contains some pure lead as well as lead monoxide, lead dioxide and lead sulfate.

[0095] Lead monoxide (PbO), also commonly referred to as lead (II) oxide, has an oxidation state of +2. PbO is formed during the discharge of the LAB by a proton-electron mechanism of the reduction of PbO2 (note that the positive plate of the LAB consists of PbO2, while the negative plate of the LAB consists of pure lead Pb).

[0096] Lead dioxide (PbO2), also commonly referred to as lead (IV) oxide, has an oxidation state of +4. The positive plate of the LAB is composed of PbO2, while the negative plate of the LAB is composed of pure lead (Pb).

[0097] Lead hydroxide (Pb(OH)2), also commonly referred to as lead (IV) oxide or less accurately as "lead hydrate" (the latter term is also used to refer to Pb(H2O)2) has a +2 oxidation state. Pb(OH)2 is produced by the interaction of the PbO2 plates in the LAB with a solution of sulfuric acid (H2SO4) in the LAB (which also produces PbSO4). As previously mentioned, lead sulfate (PbSO4) is converted to lead hydroxide (Pb(OH)2) during the desulfurization process prior to the electrolytic treatment.

[0098] In order to enable the electrolytic process to successfully recover elemental lead (Pb) from the lead oxide present in the lead slurry prepared for solid-state electrolysis, one or more supplementary chemicals may be added to the lead slurry mixture (including the electrolyte and lead oxide components) prior to the electrolytic treatment. During the electrolytic process, these supplementary chemicals will effectively cause the oxygen (O) and / or hydroxide (OH) molecules in the lead oxide to dissociate from the lead (Pb) and combine to form gaseous O2 (which may then escape from the mixture into the surrounding air) and / or liquid water (H2O) (which may then remain in the mixture and be pressed out or boiled off during subsequent treatment of the resulting elemental lead (Pb).

[0099] Figure 6is a block diagram of an example computing environment that can be used in conjunction with example implementations and aspects, such as those disclosed and described herein and in other figures presented herein. The computing system environment is only one example of a suitable computing environment and is not intended to suggest any limitation as to the scope of use or functionality.

[0100] Numerous other general or special purpose computing system environments or configurations may be used. Examples of well-known computing systems, environments, and / or configurations that may be suitable include, but are not limited to, personal computers (PCs), server computers, handheld or notebook devices, multiprocessor systems, microprocessor-based systems, network PCs, minicomputers, mainframe computers, embedded systems, distributed computing environments that include any of the above, and the like.

[0101] Computer executable instructions executed by a computer, such as program modules, may be used. Typically, program modules include routines, programs, objects, components, data structures, etc. that perform specific tasks or implement specific abstract data types. Distributed computing environments may be used in which tasks are performed by remote processing devices linked through a communication network or other data transmission medium. In a distributed computing environment, program modules and other data may be located in local and remote computer storage media (including memory storage devices).

[0102] Various illustrative logics, logic blocks, modules, and circuits related to the aspects disclosed herein may be implemented or performed with a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), an analog digital converter (ADC) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, discrete data acquisition components, or any combination designed to perform the functions described herein. A general purpose processor may be a microprocessor, but, in an alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, a combination of one or more microprocessors and a DSP core, or any other such configuration. In addition, at least one processor may include one or more modules operable to perform one or more of the steps and / or actions described above.

[0103] refer to Figure 6 , an exemplary system for implementing aspects described herein includes a computing device, such as computing device 600. In a basic configuration, computing device 600 typically includes at least one processing unit 602 and memory 604. Depending on the exact configuration and type of computing device, memory 604 may be volatile (e.g., random access memory (RAM)), non-volatile (e.g., read-only memory (ROM), flash memory, etc.), or some combination of the two. The basic configuration is Figure 6 It is shown by dotted line 606, which can be collectively referred to as the "computing" component.

[0104] The computing device 600 may have additional features / functionality. For example, the computing device 600 may include additional storage devices (removable and / or non-removable) including, but not limited to, magnetic or optical disks or tapes. Such additional storage devices may be stored in the computer system. Figure 6 600 is shown by removable storage device 608 and non-removable storage device 610. Computing device 600 typically includes a variety of computer-readable media. Computer-readable media can be any available media that can be accessed by device 600, and can include volatile and non-volatile media, as well as removable and non-removable media.

[0105] Computer storage media includes volatile and nonvolatile media, and 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. Memory 604, removable storage 608, and non-removable storage 610 are all examples of computer storage media. Computer storage media include, but are not limited to, RAM, ROM, electrically erasable program read-only memory (EEPROM), flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical storage devices, magnetic cassettes, magnetic tape, magnetic disk storage devices or other magnetic storage devices, or any other medium that can be used to store information and can be accessed by computing device 600. Any such computer storage media can be part of computing device 600.

[0106] The computing device 600 may include a communication connection 612, which enables the device to communicate with other devices. The computing device 600 may also have an input device 614, such as a keyboard, a mouse, a pen, a voice input device, a touch input device, etc. An output device 616 may also be included, such as a display, a speaker, a printer, etc. All of these devices are well known in the art and need not be discussed in detail here. The computing device 600 may be one of a plurality of computing devices 600 interconnected by a network. It is understood that the network may be any appropriate network, each computing device 600 may be connected to the network in any appropriate manner via a communication connection 612, and each computing device 600 may communicate with one or more other computing devices 600 in the network in any appropriate manner. For example, the network may be a wired or wireless network within an institution or home, etc., and may include direct or indirect coupling to an external network such as the Internet, etc. In addition, the various embodiments described herein may be embedded in other computing systems using PCI, PCIe, and other bus protocols.

[0107] Explanation of the content disclosed in this article

[0108] It should be understood that the various techniques described herein may be implemented in conjunction with hardware or software, or, where appropriate, in conjunction with both hardware and software. Thus, the methods and apparatus of the presently disclosed subject matter, or certain aspects or portions thereof, may take the form of program code (i.e., instructions) embodied in a tangible medium, such as a floppy disk, CD-ROM, hard drive, or any other machine-readable storage medium, which, when loaded into and executed by a machine (e.g., a computer), becomes an apparatus for practicing the presently disclosed subject matter.

[0109] In the case of executing program code on a programmable computer, the computing device typically includes a processor, a storage medium readable by the processor (including volatile and non-volatile memory and / or storage elements), at least one input device and at least one output device. One or more programs can implement or utilize methods related to the currently disclosed subject matter, such as by using APIs, reusable controls, etc. Such programs can be implemented in high-level procedural or object-oriented programming languages ​​to communicate with the computer system. However, the program can be implemented in assembly language or machine language. In any case, the language can be a compiled language or an interpreted language and can be combined with hardware implementation.

[0110] Although the exemplary embodiments may involve utilizing aspects of the presently disclosed subject matter in the context of one or more stand-alone computer systems, the subject matter is not so limited, but may be implemented in conjunction with any computing environment (e.g., a network or distributed computing environment). In addition, aspects of the presently disclosed subject matter may be implemented in or across multiple processing chips or devices, and storage may similarly be affected across multiple devices. For example, such devices may include PCs, network servers, and handheld devices.

[0111] Certain embodiments described herein may utilize a cloud operating environment that supports providing computing, processing, storage, data management, applications, and other functions as abstract services rather than as independent products of computer hardware, software, etc. The service may be provided by a virtual server that may be implemented as one or more processes on one or more computing devices. In some embodiments, a process may migrate between servers without interrupting cloud services. In the cloud, shared resources (e.g., computing, storage) may be provided to computers including servers, clients, and mobile devices via a network. Cloud services may be accessed using different networks (e.g., Ethernet, Wi-Fi, 802.x, cellular). Users interacting with the cloud may not need to know the detailed information (e.g., location, name, server, database, etc.) of the device that actually provides the service (e.g., computing, storage). Users may access cloud services by, for example, a web browser, a thin client, a mobile application, or other means. With respect to any physical components of the hardware and software described herein, equivalent functions provided by a cloud operating environment are also contemplated and disclosed.

[0112] In addition, the controller service can reside in the cloud and can rely on a server or service to perform processing and can rely on a data storage device or database to store data. Although a single server, a single service, a single data storage device, and a single database can be used, multiple instances of servers, services, data storage devices, and databases can reside in the cloud and can therefore be used by the controller service. Similarly, various devices can access the controller service in the cloud, and these devices can include (but are not limited to) computers, tablet computers, laptops, desktop displays, televisions, personal digital assistants, and mobile devices (e.g., cellular phones, satellite phones, etc.). Different users in different locations can access the controller service through different networks or interfaces using different devices. In one example, the controller service can be accessed by a mobile device. In another example, a portion of the controller service can reside on a mobile device. In any case, the controller service can perform operations, including, for example, presenting content on an auxiliary display, presenting an application (e.g., a browser) on an auxiliary display, presenting a cursor on an auxiliary display, presenting a control on an auxiliary display, and / or generating control events in response to interactions on a mobile device or other services. In a specific implementation, the controller service can perform part of the method described herein.

[0113] Expected alternatives

[0114] Although the subject matter has been described in language directed to structural features and / or methodological acts, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Instead, the specific features and acts described above are disclosed as example forms of implementing the claims. In addition, it will be apparent to those skilled in the art that other embodiments may be implemented in addition to the specific details disclosed above.

[0115] The above drawings and the written description of specific structures and functions below are not intended to limit the scope of the invention or the scope of the appended claims. On the contrary, the drawings and written description are provided to teach those skilled in the art to make and use the invention for which patent protection is sought. Those skilled in the art will understand that for the sake of clarity and understanding, not all features of the commercial implementation of the present invention are described or shown. Those skilled in the art will also understand that the block diagrams herein may represent conceptual views of illustrative circuits that embody technical principles, and any flow charts, state transition diagrams, pseudocodes, etc. represent various processes that can be embodied in computer-readable media and executed by a computer or processor, whether or not such a computer or processor is explicitly shown. The functions of various elements, including functional blocks, can be provided by using dedicated electronic hardware and electronic circuits capable of executing computer program instructions in association with appropriate software. Those skilled in the art will also recognize that developing an actual commercial implementation incorporating various aspects of the present invention will require making many implementation-specific decisions to achieve the ultimate goals of the developers for the commercial implementation. Such implementation-specific decisions may include, but are not limited to, compliance with system-related, business-related, government-related and other constraints that may vary by specific implementation, location and time. While a developer's efforts might be complex and time-consuming in an absolute sense, such efforts would be a routine undertaking for those skilled in the art having the benefit of this disclosure.

[0116] It should be understood that the embodiments disclosed and taught herein are susceptible to various modifications and alternative forms. Therefore, the use of singular terms (such as but not limited to "one", etc.) is not intended to limit the number of items. In addition, the use of relational terms (such as but not limited to "top", "bottom", "left", "right", "above", "below", "lower", "upper", "side", etc.) in the written description is for clarity when specifically referring to the drawings, and is not intended to limit the scope of the present invention or the appended claims. For the specific embodiments described in the block diagram and / or operating instructions of the reference method, it should be understood that each block in the block diagram and / or operating instructions and the combination of blocks in the block diagram and / or operating instructions can be implemented by analog and / or digital hardware and / or computer program instructions. The computer program instructions used with or by the embodiments disclosed herein can be written in object-oriented programming languages, conventional process programming languages, or lower-level codes (such as assembly language and / or microcode). The program can be executed entirely on a single processor and / or across multiple processors, as a stand-alone software package or as part of another software package. Such computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an ASIC, and / or other programmable data processing system. The executed instructions may also create structures and functions for implementing the actions specified in the block diagrams and / or operational descriptions mentioned. In some alternative embodiments, the functions / actions / structures shown in the figures may not occur in the order shown in the block diagrams and / or operational descriptions. For example, two operations shown as occurring in succession may actually be performed substantially simultaneously, or the operations may be performed in reverse order, depending on the functions / actions / structures involved.

[0117] The term "computer-readable instruction" used above refers to any instruction executable by a processor and / or other components. Similarly, the term "computer-readable medium" refers to any storage medium that can be used to store computer-readable instructions. Such media can take a variety of forms, including but not limited to non-volatile media, volatile media, and transmission media. Non-volatile media can include, for example, optical disks or disks, such as storage devices. Volatile media can include dynamic memory, such as main memory. Transmission media can include coaxial cables, copper wires, and optical fibers, including the wires of a bus. Transmission media can also take the form of sound waves or light waves, such as those generated during radio frequency (RF) and infrared (IR) data communications. Common forms of computer-readable media can include: for example, floppy disks, foldable disks, hard disks, magnetic tapes, any other magnetic media, CDROMs, DVDs, any other optical media, punch cards, paper tapes, any other physical media with hole patterns, RAMs, PROMs, EPROMs, FLASH EPROMs, any other memory chips or cassettes, carrier waves, or any other medium that can be read by a computer.

[0118] In the foregoing description, for the purpose of explanation and non-limiting, specific details (such as specific nodes, functional entities, technologies, protocols, standards, etc.) are set forth in order to provide an understanding of the technology. In other cases, detailed descriptions of well-known methods, devices, technologies, etc. are omitted to avoid unnecessary details that obscure the description. All stated principles, aspects, embodiments and implementations and specific examples are intended to cover structural and functional equivalents, and such equivalents include currently known equivalents and equivalents developed in the future, that is, any elements that perform the same function regardless of the structure. Although the disclosed embodiments have been described with reference to one or more specific embodiments, those skilled in the art will recognize that many changes may be made thereto. Therefore, each of the aforementioned embodiments and their obvious changes are considered to belong to the spirit and scope of the disclosed embodiments, which are set forth in the following claims.

[0119] Copyright Notice

[0120] Portions of the disclosure of this patent document contain material that is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.

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Claims

1. A method (60') for recovering a nearly pure metal from an impure metal material (130) containing a target metal, the method (60') comprising: combining (68) the impure metal material (130) with an electrolyte (140) to form a slurry (150), the slurry (150) being a mixture of the impure metal material (130) and the electrolyte (140), such that the electrolyte (140) does not dissolve the target metal in the impure metal material (130); performing solid-state electrolysis (72) on the slurry (150) to form a target metal deposit (132) and a residual component (142); mechanically separating (74) the target metal from substantially all of the electrolyte (140) and at least some of the residual components (142); as well as The target metal deposit (132) is melted (80) and dross is removed so that the remaining molten target metal is nearly pure without the need for smelting.

2. The method (60') of claim 1, further comprising adding (68) at least one supplemental chemical to the slurry (150) prior to performing the solid-state electrolysis (72).

3. The method (60') of claim 2, further comprising mechanically separating (92) the dross into component materials for further processing.

4. The method (60') according to claim 3, wherein: The impure metal material (130) includes a first impure form of the target metal and a second impure form of the target metal, the first impure form being chemically different from the second impure form.

5. The method (60') according to claim 4, wherein: The impure metal material (130) includes a third impure form of the target metal, the third impure form being chemically different from the first impure form and the second impure form.

6. The method (60') according to claim 5, wherein: The target metal formed during solid-state electrolysis (72) is extracted from the first impure form, the second impure form, and the third impure form.

7. The method (60') according to claim 6, wherein: The at least one supplemental chemical includes a first supplemental chemical, a second supplemental chemical, and a third supplemental chemical, wherein the first supplemental chemical enables solid-state electrolysis (72) of the first impure form, the second supplemental chemical enables solid-state electrolysis (72) of the second impure form, and the third supplemental chemical enables solid-state electrolysis (72) of the third impure form.

8. The method (60') according to claim 7, wherein: The target metal is elemental lead (Pb), wherein the first impure form is lead monoxide (PbO), wherein the second impure form is lead dioxide (PbO2), and wherein the third impure form is lead hydroxide (Pb(OH)2).

9. The method (60') of claim 8, further comprising desulfurizing (66) the impure metallic material (130) prior to combining (68) the impure metallic material (130) with the electrolyte (140) to form the slurry (150).

10. The method (60') according to claim 9, wherein: The solid-state electrolysis (72) is performed using an electrolyzer including a horizontal cathode (120) on which the slurry (150) is placed to perform the solid-state electrolysis (72).

11. A system (100) for recovering near-pure metal from an impure metal material (130) containing a target metal, the system (100) comprising at least one subsystem, the at least one subsystem being configured to: combining (68) the impure metal material (130) with an electrolyte (140) to form a slurry (150), the slurry (150) being a mixture of the impure metal material (130) and the electrolyte (140), such that the electrolyte (140) does not dissolve the target metal in the impure metal material (130); performing solid-state electrolysis (72) on the slurry (150) to form a target metal deposit (132) and a residual component (142); mechanically separating (74) the target metal from substantially all of the electrolyte (140) and at least some of the residual components (142); and The target metal deposit (132) is melted (80) and dross is removed so that the remaining molten target metal is nearly pure without the need for smelting.

12. The system (100) of claim 11, further comprising at least one subsystem for adding (68) at least one supplemental chemical to the slurry (150) prior to performing the solid-state electrolysis (72).

13. The system (100) of claim 11, further comprising at least one subsystem for mechanically separating (92) the dross into component materials for further processing.

14. The system (100) of claim 11, wherein: The impure metal material (130) includes a first impure form of the target metal, a second impure form of the target metal, and a third impure form of the target metal, the first impure form being chemically different from the second impure form, and the third impure form being chemically different from the first impure form and the second impure form.

15. An apparatus (10) for recovering nearly pure lead from an impure lead paste (130) containing one or more of lead monoxide (PbO), lead dioxide (PbO2) or lead hydroxide (Pb(OH)2), the apparatus (10) comprising: A mixer (26) for combining the impure lead paste (130) with an electrolyte (140) to form a slurry (150), wherein the slurry (150) is a mixture of the impure lead paste (130) and the electrolyte (140), so that the electrolyte (140) does not dissolve lead monoxide (PbO), lead dioxide (PbO2) or lead hydroxide (Pb(OH)2) in the lead paste (130); an electrolyzer (28) for performing solid-state electrolysis (72) on the slurry (150) to form sponge lead (132) and a residual component (142), wherein a portion of the electrolyte (142) may be discharged from the residual component (142) when the solid-state electrolysis (72) is completed; a converter (30) including a press for mechanically separating (92) said spongy lead (132) from substantially all of the remaining electrolyte (140) and producing lead bricks; as well as A melter (32) for melting (80) the lead bricks into molten lead and dross, wherein only nearly pure lead (48) remains after the dross is removed.

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