Method and system for purifying metal or metal alloy

Abstract

Methods and systems for purifying metals or metal alloys are provided. The method includes disposing a molten material predominantly comprising aluminum and at least one first metal having an atomic mass of less than 13 in a first region of an electrolytic cell. The electrolytic cell includes an anode, a cathode, and a molten salt electrolyte in contact with the anode and the cathode. The method includes contacting the anode with the molten material, and applying a voltage across the anode and the cathode such that at least a portion of the first metal in the molten material migrates to a third region in the electrolytic cell to produce a first material rich in the first metal. The method includes removing at least a first portion of the first material in the third region from the electrolytic cell.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Patent Application No. 63 / 490,057 filed on March 14, 2023, the contents of which are incorporated by reference into this specification. Technical Field

[0003] The present disclosure relates to methods and systems for purifying metals or metal alloys. Background Art

[0004] Some metals and metal alloys may require purification before use. For example, aluminum raw materials can be purified for use according to the method disclosed in U.S. Patent No. 10,407,786. However, there are challenges in purifying metals and metal alloys. Summary of the invention

[0005] According to a non-limiting aspect of the present disclosure, a method is provided, which includes placing a molten material mainly containing aluminum and at least one first metal with an atomic mass less than 13 in a first region of an electrolytic cell. The electrolytic cell includes an anode, a cathode, and a molten salt electrolyte in contact with the anode and the cathode. The molten salt electrolyte is arranged in a second region of the electrolytic cell. The method includes contacting the anode with the molten material, and applying a voltage to the anode and the cathode so that at least a portion of the first metal in the molten material migrates to a third region in the electrolytic cell to produce a first material rich in the first metal. The second region is between the first region and the third region. The method includes removing at least a first portion of the first material in the third region from the electrolytic cell.

[0006] According to another non-limiting aspect of the present disclosure, a method is provided, which includes placing a molten material mainly containing aluminum and lithium in a first region of an electrolytic cell. The electrolytic cell includes an anode, a cathode, and a molten salt electrolyte in contact with the anode and the cathode. The molten salt electrolyte is arranged in a second region of the electrolytic cell. The method includes contacting the anode with the molten material, and applying a voltage to the anode and the cathode so that at least a portion of the lithium in the molten material migrates to a third region in the electrolytic cell to produce a first material rich in lithium. The second region is between the first region and the third region. The method includes removing at least a first portion of the first material in the third region from the electrolytic cell.

[0007] Yet another non-limiting aspect of the present disclosure relates to a method comprising feeding an aluminum feedstock into an aluminum electrolysis cell. The method comprises directing an electric current into an anode, through an electrolyte, and into a cathode. At least a portion of a surface of the anode is wetted with a portion of the aluminum feedstock. Accompanying the directing of the electric current, at least a portion of at least one of lithium, beryllium, sodium, and magnesium in the aluminum feedstock migrates to a location within the cell. The method comprises removing the migrated lithium, beryllium, sodium, and magnesium from the cell, thereby producing a purified product.

[0008] It should be understood that the invention disclosed and described in this specification is not limited to the aspects outlined in this summary. The reader will appreciate the foregoing details as well as other details after considering the following detailed description of various non-limiting and non-exhaustive aspects according to the present specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Features and advantages of the examples and the manner in which they are achieved will become more apparent and the examples will be better understood by referring to the following description taken in conjunction with the accompanying drawings, in which:

[0010] Figure 1 is a flow chart illustrating a non-limiting embodiment of a method for purifying metals and metal alloys according to the present disclosure; and

[0011] Figure 2 is a schematic side view of a non-limiting embodiment of an electrolytic cell for purifying metals and metal alloys according to the present disclosure.

[0012] The exemplifications set out herein illustrate certain embodiments, in one form, and such exemplifications should not be construed as limiting the scope of the appended claims in any way. DETAILED DESCRIPTION

[0013] Various embodiments are described and illustrated herein to provide an overall understanding of the structure, function and use of the disclosed articles and methods. The various embodiments described and illustrated herein are non-restrictive and non-exhaustive. Therefore, the present invention is not limited by the description of the various non-restrictive and non-exhaustive embodiments disclosed herein. On the contrary, the present invention is limited only by the claims. The features and characteristics illustrated and / or described in conjunction with the various embodiments can be combined with the features and characteristics of other embodiments. Such modifications and changes are intended to be included within the scope of this specification. Thus, the claims may be amended to state any features or characteristics that are explicitly or inherently described or otherwise explicitly or inherently supported in this specification. In addition, the applicant reserves the right to amend the claims to affirmatively deny features or characteristics that may exist in the prior art. The various embodiments disclosed and described in this specification may include the features and characteristics described herein, be composed of the features and characteristics described herein, or be substantially composed of the features and characteristics described herein.

[0014] Various non-limiting embodiments of the alloys discussed in conjunction with the present disclosure optionally include intentional additions of incidental elements that may, for example, aid in the production of the alloy and / or improve one or more properties or characteristics of the alloy. In various non-limiting embodiments, the total concentration of incidental elements in the alloys according to the present disclosure preferably does not exceed 1 wt %, based on the total weight of the alloy, and the concentration of any single incidental element preferably does not exceed 0.2 wt %, based on the total weight of the alloy.

[0015] Various non-limiting embodiments of alloys discussed in conjunction with the present disclosure may include impurities. As used herein, "impurities" are elements or other materials that may be present in alloys according to the present disclosure in relatively small concentrations but are not intentionally added to enhance production or affect the properties or characteristics of the alloy. For example, impurities in alloys according to the present disclosure may be present in smaller concentrations due to, for example, the inevitable or unintentional presence of impurities in feed materials, mixing from the local atmosphere during melting, refining or other processing, or contamination due to contact with processing equipment. In various non-limiting embodiments, the total concentration of impurities in the alloys discussed in the present disclosure is preferably no more than 0.15% by weight, based on the total weight of the alloy, and the concentration of any single impurity is preferably no more than 0.05% by weight, based on the total weight of the alloy.

[0016] Aluminum alloys containing metals with atomic numbers less than 13 can have desirable properties. For example, aluminum-lithium alloys can have lower densities than conventional aluminum alloys and are therefore ideal for reducing the weight of aerospace parts while also maintaining high strength. Parts made from aluminum-lithium alloys can be much more expensive than parts made from alloys that do not contain lithium. Due to its inherent cost, lithium is an expensive alloying additive, and aerospace and automotive parts produced from aluminum-lithium alloys can require extensive machining, which generates a large amount of machining chips.

[0017] Machining chips and / or scraps of aluminum alloys including metals having an atomic number less than 13 may require specialized processing and may also need to be processed separately from, for example, other aluminum alloys. Machining chips and / or scraps of aluminum alloys including metals having an atomic number less than 13 may only be reused for other specialized aluminum alloys and may not be compatible with certain applications. The present disclosure provides methods and systems for purifying metals or metal alloys. The methods and systems can improve the recyclability of machining chips and / or scraps of alloys including primarily aluminum and metals having an atomic number less than 13, thereby reducing material losses in machining operations and recovering processing streams with high material value.

[0018] Figure 1 A block diagram of a non-limiting embodiment of a method for separating elements from a molten material according to the present disclosure is provided. The molten material ( Figure 1 , step 102) to prepare a molten material mainly comprising aluminum and a first metal. For example, the feedstock may be a solid that is heated until substantially melted and capable of flowing. In various embodiments, the heating may be performed in a furnace under an inert atmosphere.

[0019] The feedstock may include various forms of aluminum alloys, such as, for example, machined chips, solid ingots, scrap, and other forms. In embodiments including a feedstock comprising machined chips, the machined chips may be cleaned prior to heating the feedstock. In various non-limiting embodiments, the feedstock may include material processed according to the method described in International Application No. PCT / US2022 / 012740, filed on January 18, 2022, which is incorporated herein by reference in its entirety.

[0020] The aluminum alloy of the raw material may include a first metal, aluminum, incidental elements and impurities. The atomic number of the first metal is less than 13. For example, the first metal may be at least one of lithium, beryllium, sodium and magnesium. In various examples, the first metal may be at least one of lithium and magnesium. In certain non-limiting embodiments, the aluminum alloy may include at least two first metals selected from lithium, beryllium, sodium and magnesium.

[0021] In various non-limiting embodiments, the raw material may include an aluminum-lithium alloy. As used herein, "aluminum-lithium alloy" is an alloy comprising 0.1 wt % to 5 wt % of lithium, aluminum, incidental elements and impurities. In various non-limiting embodiments, the aluminum-lithium alloy may include at least 0.5 wt % of lithium, such as, for example, at least 1 wt %, at least 1.5 wt %, at least 2 wt % or at least 2.5 wt % of lithium, all based on the gross weight of the aluminum-lithium alloy. In various forms, the aluminum-lithium alloy may include 0.1 wt % to 0.5 wt %, 0.2 wt % to 3 wt %, 0.2 wt % to 2 wt %, 0.5 wt % to 2 wt %, 0.5 wt % to 2.5 wt % or 1 wt % to 5 wt % of lithium, with the remainder being aluminum, incidental elements and impurities. As known in the art, some aluminum-lithium alloys may include additional intentional alloying additives, such as copper, manganese, magnesium, zinc, titanium, zirconium, silicon, iron, chromium and silver. Commercially available aluminum-lithium alloys that may be included in the feedstock may include one or more aluminum-lithium alloys in the 2099, 2199, 2050, 2055, 2060, 2090, 8090, 2195, 2397, and 2070 series, all of which are defined in Teal Sheets published by the Aluminum Association (last revised in August 2018). In various non-limiting embodiments, the feedstock may include at least 80% by weight aluminum based on the total weight of the feedstock, such as, for example, at least 85% by weight aluminum, at least 90% by weight aluminum, or at least 95% by weight aluminum, all based on the total weight of the feedstock.

[0022] Based on the total weight of the molten material, the sum of lithium, beryllium, sodium and magnesium in the molten material can be 0.1 wt % to 10 wt %. In various embodiments, the molten material can include 0.1 wt % to 0.5 wt %, 0.2 wt % to 3 wt %, 0.2 wt % to 2 wt %, 0.5 wt % to 2 wt %, 0.5 wt % to 2.5 wt %, 0 wt % to 5 wt % lithium or 1 wt % to 5 wt % lithium based on the total weight of the molten material. In various embodiments, the molten material can include 0 wt % to 10 wt %, 0.1 wt % to 10 wt %, 0.2 wt % to 9 wt %, 0.2 wt % to 8 wt %, 0.5 wt % to 2 wt %, 0.5 wt % to 2.5 wt %, or 1 wt % to 5 wt % magnesium based on the total weight of the molten material. In various embodiments, the molten material may include 0% to 0.05%, 0.005% to 0.05%, 0.005% to 0.01%, or 0% to 0.01% sodium based on the total weight of the molten material. In various embodiments, the molten material may include 0% to 0.1%, 0.0001% to 0.1%, 0% to 0.07%, or 0.0001% to 0.07% beryllium based on the total weight of the molten material. In certain embodiments, the molten material may include the sum of sodium and beryllium less than 0.05% by weight based on the total weight of the molten material.

[0023] The method includes placing a molten material in a first region of an electrolytic cell ( Figure 1 , step 104). Figure 2 , the electrolytic cell 200 may include a first region 200a, a second region 200b, a third region 200c, an anode 204, a cathode 206, and a molten salt electrolyte in contact with the anode 204 and the cathode 206. The electrolytic cell 200 may include a refractory wall 200e, the refractory wall defining a cavity 200d, the cavity including the first region 200a, the second region 200b, and the third region 200c. The third region 200c is above the second region 200b in the cavity 200d, and the second region 200b is between the third region 200c and the first region 200a in the cavity 200d. In various non-limiting embodiments, the molten material may be fed into the first region 200a in the cavity 200d of the electrolytic cell 200 through the port 214.

[0024] Cathode 206 extends from the first side 210 of electrolytic cell 200 into chamber 200d, through the third region 200c, and into the second region 220b. Cathode 206 may not contact the first region 200a in chamber 200d. Anode 204 extends from the second side 212 of electrolytic cell 200 through the first region 200a and into the second region 200b. Anode may not contact the third region 200c in chamber 200d. Anode 204 may be an elongated vertical anode, and cathode 206 may be an elongated vertical cathode. Anode 204 and cathode 206 may be electrically connected to an external power supply so as to form a circuit comprising anode 204, cathode 206, molten salt electrolyte and an external power supply.

[0025] The anode 204 and the cathode 206 may be arranged within the chamber 200d of the electrolytic cell 200 to form an anode-cathode overlap (ACO). As used herein, "anode-cathode overlap" (ACO) means the distance d from the distal end 204a of the anode 204 to the distal end 206a of the cathode 206. ACO In some embodiments, the distance d ACO The distance d may be in the range of 0 inches to 50 inches, such as, for example, 1 inch to 50 inches, 5 inches to 50 inches, 10 inches to 50 inches, 20 inches to 50 inches, 25 inches to 50 inches, 0 inches to 12 inches, 2 inches to 10 inches, 3 inches to 8 inches, or 3 inches to 6 inches. In various non-limiting embodiments, the distance d ACO is the vertical distance.

[0026] Anode 204 and cathode 206 may be arranged within chamber 200d of electrolytic cell 200 to form an anode-to-cathode spacing (ACS). As used herein, "anode-to-cathode spacing" (ACS) means the distance d separating side 204b of anode 204 from side 206b of cathode 206. ACS In some embodiments, the distance d ACS The distance d may be in the range of 0.125 inches to 3 inches, such as, for example, 0.125 inches to 1 inch, 0.125 inches to 0.250 inches, 0.250 inches to 0.5 inches, 0.125 inches to 0.75 inches, 0.125 inches to 1 inch, or 0.125 inches to 0.5 inches. In various non-limiting embodiments, the distance d ACS is the horizontal distance.

[0027] In various non-limiting embodiments, there may be at least two cathodes 206 and at least two anodes 204. The cathodes 206 and anodes 204 may be configured in pairs with respective distances d ACO and d ACS .

[0028] Anode 204 and cathode 206 can each include at least one of a lithium wettable material, a beryllium wettable material, a sodium wettable material, and a magnesium wettable material. For example, anode 204 and cathode 206 can each include a lithium wettable material. In various non-limiting embodiments, anode 204 can include at least one of TiB2, ZrB2, HfB2, SrB2, a carbon material, W, Mo, and steel, and cathode 206 can include at least one of TiB2, ZrB2, HfB2, SrB2, and a carbon material. The wettable materials of anode 204 and cathode 206 can be applied to the corresponding electrodes as a coating. The wettable material can promote the migration of the first metal in the entire cavity 200d, for example, from the first region 200a to the third region 200c.

[0029] The molten salt electrolyte may be disposed in the second region 200b of the electrolytic cell 200. The molten material in the first region 200a has a first density, the molten salt electrolyte in the second region 200b has a second density, and the first material in the third region 200c has a third density. The first density is greater than the second density, and the second density is greater than the third density. Therefore, the molten material, the molten salt electrolyte, and the first material may form separate layers in the electrolytic cell 200, so that the molten salt electrolyte floats on the molten material in the chamber 200d, and the first material floats on the molten salt electrolyte in the chamber 200d.

[0030] The molten salt electrolyte may include a composition suitable for achieving a second density, support the migration of the first metal from the first region 200a to the third region 200c, and enable a suitable current to flow between the anode 204 and the cathode 206. For example, the molten salt electrolyte may include at least one of a molten lithium salt, a molten beryllium salt, a molten sodium salt, and a molten magnesium salt. For example, the molten salt electrolyte may include a molten lithium salt. In various non-limiting embodiments, the molten salt electrolyte may include at least one of a molten fluoride salt and a molten chloride salt, such as, for example, at least one of sodium fluoride, potassium fluoride, and barium fluoride.

[0031] In various non-limiting embodiments, an inert gas atmosphere may be provided within the electrolytic cell 200 by flowing an inert gas into the electrolytic cell 200. For example, the inert gas atmosphere may include at least one of nitrogen and argon. The inert gas atmosphere may be positioned above the third region 200c in the fourth region 200f.

[0032] Reference again Figure 1 The method may include contacting the anode 204 with the molten material and applying a voltage to the anode 204 and the cathode 206 so that at least a portion of the first metal in the molten material migrates to the third region 200c in the electrolytic cell 200 to produce the first material ( Figure 1, step 106). For example, an electric current can be directed into anode 204, through the molten salt electrolyte, and into cathode 206. At least a portion of anode 204 can be wetted with at least a portion of the molten material. For example, the first metal can wet anode 204. Thereafter, along with the directing of the electric current, at least a portion of the first metal can migrate to a location in third region 200c of electrolytic cell 200, which can enrich the concentration of the first metal in the first material.

[0033] Without being bound by any particular theory, it is believed that the anode 204 is configured to undergo an electrochemical reaction such that the first metal is anodized to form ions that are transported to the electrolyte. The ions are then reduced on the cathode 206 and form a purified first metal. In various non-limiting embodiments, impurities may remain on the surface of the anode 204 and / or the first region 200a. Without being bound by any particular theory, it is believed that due to the buoyancy of the purified first metal in the molten salt electrolyte, the purified first metal can slowly move to the surface of the cathode 206 and into the third region 200c.

[0034] Reference again Figure 1 The method includes removing at least a first portion of the first material in the third region 200c from the electrolytic cell 200. Figure 1 , step 108). Removing the first material can include tapping the electrolytic cell and / or siphoning away the first material. In various non-limiting embodiments, the first portion of the first material can be removed from the cavity 200d of the electrolytic cell 200 through the port 216.

[0035] The first material may be a purified product. In various non-limiting embodiments, the first portion removed from the third region 200c of the electrolytic cell 200 may include at least 95% by weight of the first metal based on the total weight of the first portion. For example, in certain embodiments, the first portion removed from the third region 200c of the electrolytic cell 200 may include at least 95% by weight of lithium based on the total weight of the first portion.

[0036] Reference again Figure 1 The method may include casting the first portion removed from the electrolytic cell 200 into an ingot and / or introducing the first portion removed from the electrolytic cell 200 into a furnace as a raw material for producing a metal or metal alloy ( Figure 1 , step 110). The first part can be used to produce a product, such as at least one of an aviation part and an automobile part.

[0037] In various non-limiting embodiments, the method includes removing at least a second material ( Figure 1, step 112). The second material can be enriched in aluminum and / or deficient in the first metal. For example, the molten material can include a first aluminum concentration based on the total weight of the molten material, the second material can include a second aluminum concentration based on the total weight of the second material, and the second aluminum concentration can be greater than the first aluminum concentration. The second aluminum concentration can be at least 95% by weight aluminum based on the total weight of the second material, such as, for example, at least 96% by weight, at least 97% by weight, at least 98% by weight, at least 99% by weight, at least 99.9% by weight, or at least 99.99% by weight aluminum, all based on the total weight of the second material.

[0038] In various non-limiting embodiments, the second material can be removed from the chamber 200d of the electrolytic cell 200 through the port 218. The port 218 can be disposed at an end of the electrolytic cell 200 opposite the end of the electrolytic cell where the port 214 is disposed, such that a continuous flow of material is generated from the port 214 through the first region 200a to the port 218. The process can be a batch process, a continuous process, or a semi-continuous process.

[0039] The following numbered clauses are directed to various non-limiting embodiments and aspects according to the present disclosure.

[0040] Item 1. A method comprising: placing a molten material primarily comprising aluminum and at least one first metal with an atomic mass less than 13 in a first region of an electrolytic cell, the electrolytic cell comprising an anode, a cathode, and a molten salt electrolyte in contact with the anode and the cathode, wherein the molten salt electrolyte is placed in a second region of the electrolytic cell; contacting the anode with the molten material, and applying a voltage across the anode and the cathode such that at least a portion of the first metal in the molten material migrates to a third region in the electrolytic cell to produce a first material rich in the first metal, wherein the second region is intermediate the first region and the third region; and removing at least a first portion of the first material in the third region from the electrolytic cell.

[0041] Item 2. The method of Item 1, further comprising heating a feedstock comprising an aluminum alloy to form a molten material.

[0042] Clause 3. The method of clause 2, wherein the feedstock comprises machining chips comprising an aluminum alloy.

[0043] Item 4. The method of Item 3, further comprising cleaning the machining chips before heating the feedstock comprising the machining chips.

[0044] Clause 5. The method of any of clauses 1-4, further comprising removing at least a second material from a first region of the electrolytic cell, wherein the molten material comprises a first aluminum concentration based on the total weight of the molten material, the second material comprises a second aluminum concentration based on the total weight of the second material, and the second aluminum concentration is greater than the first aluminum concentration.

[0045] Clause 6. The method of any of Clauses 1-5, further comprising casting the first portion removed from the electrolytic cell into an ingot.

[0046] Clause 7. The method of any of Clauses 1-6, further comprising introducing the first portion removed from the electrolytic cell into a furnace as a feedstock for producing a metal or metal alloy.

[0047] Clause 8. The method of any of Clauses 1-7, wherein the anode and cathode each comprise at least one of a lithium wettable material, a beryllium wettable material, a sodium wettable material, and a magnesium wettable material.

[0048] Clause 9. The method of any of Clauses 1-8, wherein the anode and cathode each comprise a lithium wettable material.

[0049] Clause 10. The method of any of clauses 1-9, wherein the sum of lithium, beryllium, sodium, and magnesium in the molten material is from 0.1 wt % to 10 wt %, based on the total weight of the molten material.

[0050] Clause 11. The method of any of Clauses 1-10, wherein the molten material comprises 0.1 wt % to 5 wt % lithium, based on the total weight of the molten material.

[0051] Clause 12. The method of Clause 11, wherein the first portion removed from the third region of the electrolytic cell comprises at least 95 wt % lithium based on the total weight of the first portion.

[0052] Clause 13. The method of any of Clauses 11-12, wherein the molten salt electrolyte comprises a molten lithium salt.

[0053] Clause 14. The method of any of clauses 1-13, wherein the molten salt electrolyte comprises at least one of a molten lithium salt, a molten beryllium salt, a molten sodium salt, and a molten magnesium salt.

[0054] Clause 15. The method of any one of clauses 1-14, wherein the method is a batch process.

[0055] Clause 16. The method of any one of clauses 1-15, wherein the method is a continuous process.

[0056] Clause 17. The method of any of clauses 1-16, wherein the molten material has a first density, the molten salt electrolyte has a second density, the first material has a third density, the first density is greater than the second density, and the second density is greater than the third density.

[0057] Clause 18. The method of any of clauses 1-17, wherein the cathode extends from the first side of the electrolytic cell through the third region and into the second region, the anode extends from the second side of the electrolytic cell through the first region into the second region, the cathode does not contact the first region, and the anode does not contact the third region.

[0058] Clause 19. The method of any of Clauses 1-18, further comprising providing an inert gas atmosphere within the electrolytic cell.

[0059] Item 20. A method comprising: placing a molten material primarily comprising aluminum and lithium in a first region of an electrolytic cell, the electrolytic cell comprising an anode, a cathode, and a molten salt electrolyte in contact with the anode and the cathode, wherein the molten salt electrolyte is placed in a second region of the electrolytic cell; contacting the anode with the molten material, and applying a voltage across the anode and the cathode such that at least a portion of the lithium in the molten material migrates to a third region in the electrolytic cell to produce a first material rich in lithium, wherein the second region is intermediate the first region and the third region; and removing at least a first portion of the first material in the third region from the electrolytic cell.

[0060] Item 21. A method comprising: feeding an aluminum feedstock into an aluminum electrolysis cell; directing an electric current into an anode, through an electrolyte, and into a cathode; wetting at least a portion of a surface of the anode with a portion of the aluminum feedstock; migrating at least a portion of at least one of lithium, beryllium, sodium, and magnesium in the aluminum feedstock to a location within the cell as the electric current is directed; and removing at least a portion of the migrated lithium, beryllium, sodium, and magnesium from the cell to produce a purified product.

[0061] Clause 22. A product produced using the first fraction produced by the method according to any one of clauses 1 to 20 or the purified product according to clause 21.

[0062] Clause 23. The product of Clause 22, wherein the product comprises at least one of an aviation part and an automotive part.

[0063] As used herein, "at least one" in a list of elements or other items means one of the elements / items or any combination of two or more of the listed elements / items. As an example, "at least one of A, B, and C" means only A; only B; only C; A and B; A and C; B and C; or any one of A, B, and C.

[0064] Any reference to "various embodiments", "some embodiments", "one embodiment", "an embodiment", "non-limiting embodiment" or similar phrases herein means that the specific features, structures, steps or characteristics described in conjunction with the examples are included in at least one embodiment. Therefore, the phrases "various embodiments", "some embodiments", "one embodiment", "an embodiment", "non-limiting embodiment" or similar phrases appearing in the specification do not necessarily refer to the same embodiment. In addition, in one or more embodiments, the specific features, structures, steps or characteristics described may be combined in any suitable manner. Therefore, the specific features, structures, steps or characteristics illustrated or described in conjunction with one embodiment may be combined in whole or in part with the features, structures, steps or characteristics of one or more other embodiments without limitation. Such modifications and variations are intended to be included within the scope of the embodiments disclosed herein.

[0065] Throughout this specification, unless otherwise indicated, all numerical parameters should be construed as being preceded in all instances by the term "about" and modified by the term "about", wherein the numerical parameter is characterized by the inherent variability of the underlying measurement technology employed to determine the numerical value of the parameter. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter described herein should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0066] In addition, any numerical range listed herein includes all subranges included in the listed range. For example, the range "1 to 10" includes all subranges between the minimum value 1 and the maximum value 10 (and including the end value), that is, the minimum value is equal to or greater than 1, and the maximum value is equal to or less than 10. Moreover, all ranges listed herein include the endpoints of the listed ranges. For example, the range of "1 to 10" includes endpoints 1 and 10. Any maximum numerical limit described in this specification is intended to include all lower numerical limits included therein, and any minimum numerical limit described in this specification is intended to include all higher numerical limits included therein. Therefore, the applicant reserves the right to modify this specification (including claims) to explicitly describe any subranges included in the range explicitly described herein. All these ranges are inherently described in this specification.

[0067] As used herein, the grammatical articles "a," "an," and "the" are intended to include "at least one" or "one or more," unless otherwise indicated, even though "at least one" or "one or more" are expressly used in certain instances. Thus, the aforementioned grammatical articles are used herein to refer to one or more than one (i.e., "at least one") of a particular identified element. Furthermore, the use of a singular noun includes the plural, and the use of a plural noun includes the singular, unless the context of use requires otherwise.

[0068] Those skilled in the art will recognize that, for the sake of conceptual clarity, the articles and methods described herein and the accompanying discussions thereof are used as examples, and various configuration modifications are contemplated. Therefore, as used herein, the specific examples / embodiments and the attached discussions set forth are intended to represent their more general categories. In general, any particular example is used to represent its category, and the exclusion of specific components, devices, operations / actions, and objects should not be considered as restrictive. Although the present disclosure provides descriptions of various specific aspects for illustrating various aspects of the present disclosure and / or its potential applications, it should be understood that those skilled in the art will expect changes and modifications. Therefore, one or more inventions described herein should be understood to be at least as wide as claimed, rather than being more narrowly defined than the specific illustrative aspects provided herein.

Claims

1. A method, comprising: placing a molten material comprising primarily aluminum and at least one first metal with an atomic mass less than 13 in a first region of an electrolytic cell, the electrolytic cell comprising an anode, a cathode, and a molten salt electrolyte in contact with the anode and the cathode, wherein the molten salt electrolyte is disposed in a second region of the electrolytic cell; contacting the anode with the molten material and applying a voltage to the anode and the cathode so that at least a portion of the first metal in the molten material migrates to a third region in the electrolytic cell to produce a first material rich in the first metal, wherein the second region is intermediate the first region and the third region; as well as At least a first portion of the first material in the third region is removed from the electrolytic cell. 2 . The method of claim 1 , further comprising heating a feedstock comprising an aluminum alloy to form the molten material.

3. The method of claim 2, wherein the feedstock comprises machining chips comprising an aluminum alloy. 4 . The method of claim 3 , further comprising cleaning the machining chips before heating the feedstock containing the machining chips.

5. The method of claim 1 , further comprising removing at least a second material from the first region of the electrolytic cell, wherein the molten material comprises a first aluminum concentration based on the total weight of the molten material, the second material comprises a second aluminum concentration based on the total weight of the second material, and the second aluminum concentration is greater than the first aluminum concentration.

6. The method of claim 1, further comprising casting the first portion removed from the electrolytic cell into an ingot.

7. The method of claim 1, further comprising introducing the first portion removed from the electrolytic cell into a furnace as a feedstock for producing a metal or a metal alloy.

8. The method of claim 1, wherein the anode and the cathode each comprise at least one of a lithium wettable material, a beryllium wettable material, a sodium wettable material, and a magnesium wettable material.

9. The method of claim 1, wherein the anode and cathode each comprise a lithium wettable material.

10. The method of claim 1, wherein the sum of lithium, beryllium, sodium and magnesium in the molten material is 0.1 wt% to 10 wt% based on the total weight of the molten material.

11. The method of claim 1, wherein the molten material comprises 0.1 wt% to 5 wt% lithium based on the total weight of the molten material.

12. The method of claim 11, wherein the first portion removed from the third region of the electrolytic cell comprises at least 95 wt% lithium based on the total weight of the first portion.

13. The method of claim 11, wherein the molten salt electrolyte comprises a molten lithium salt.

14. The method of claim 1, wherein the molten salt electrolyte comprises at least one of a molten lithium salt, a molten beryllium salt, a molten sodium salt, and a molten magnesium salt.

15. The method of claim 1, wherein the method is a batch process.

16. The method of claim 1, wherein the method is a continuous process.

17. The method of claim 1, wherein the molten material has a first density, the molten salt electrolyte has a second density, the first material has a third density, the first density is greater than the second density, and the second density is greater than the third density.

18. The method of claim 1, wherein the cathode extends from a first side of the electrolytic cell through the third region and into the second region, the anode extends from a second side of the electrolytic cell through the first region into the second region, the cathode does not contact the first region, and the anode does not contact the third region.

19. The method of claim 1, further comprising providing an inert gas atmosphere within the electrolytic cell.

20. A method comprising: placing a molten material mainly comprising aluminum and lithium in a first region of an electrolytic cell, the electrolytic cell comprising an anode, a cathode, and a molten salt electrolyte in contact with the anode and the cathode, wherein the molten salt electrolyte is placed in a second region of the electrolytic cell; contacting the anode with the molten material and applying a voltage across the anode and the cathode so that at least a portion of the lithium in the molten material migrates to a third region in the electrolytic cell to produce a lithium-rich first material, wherein the second region is intermediate the first region and the third region; as well as At least a first portion of the first material in the third region is removed from the electrolytic cell.

21. A method comprising: feeding aluminum-containing raw materials into an aluminum electrolysis cell; directing an electric current into the anode, through the electrolyte, and into the cathode; wetting at least a portion of the surface of the anode with a portion of the aluminum feedstock; In response to the directing of the electric current, at least a portion of at least one of lithium, beryllium, sodium, and magnesium in the aluminum feedstock migrates to a location within the cell; and Migrated lithium, beryllium, sodium, and magnesium are removed from the cell, yielding a purified product.

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