Patent Application
20250019838
Coal has been mined and used for a variety of purposes for thousands of years. Since the industrial revolution, the primary use for coal has been to generate heat and energy to power homes, industry, and transportation. Coal initially found widespread use as a transportation fuel for trains during the industrial revolution, but the advent of cars and the discovery of large petroleum deposits near the turn of the twentieth century precipitated a shift towards the primacy of liquid, petroleum-based fuels for transportation.
Research on coal continued, however, and the basic chemistry of coal was well understood by at least the early twentieth century. Although significant research has been conducted on coal liquefaction for more than a century, this extensive prior work has overwhelmingly been focused on the development of transportation fuels. The use of coal to produce other materials of greater industrial relevance has yet to be fully explored. For example, carbon-based technologies have come to the fore in recent years, with rapid developments being made in the commercialization of advanced carbon materials such as carbon fiber, graphene, graphite, and carbon nanotubes. As these advanced materials are increasingly used in mass produced, high volume applications, there is a need to quickly and economically supply large quantities of advanced carbon materials to manufacturers. Thus, while transportation fuels from coal are not viewed as a fruitful avenue for commercialization, there remains significant work to be done in developing processes to convert coal into the advanced carbon materials that will be instrumental in the economy of the future.
A method of producing graphite includes beneficiating an amount of coal to form a coal char, grinding the coal char to produce a crushed char, placing the crushed char in a porous container, and immersing the porous container in a molten salt bath. The molten salt bath can include a graphite anode. The method can further include applying an electrical potential across the porous container and the graphite anode such that a graphite deposit forms in the porous container, removing the graphite anode from the molten salt bath, and separating the graphite deposit from the graphite anode to produce graphite fragments.
In some embodiments, beneficiating the amount of coal includes heating the amount of coal in an inert atmosphere to between about 600° C. and about 1000° C. to remove volatile components and impurities. Beneficiating the amount of coal can include heating the amount of coal in an indirectly heated rotary kiln. The crushed char can include a particle diameter of less than about 100 microns. The porous container can include a mesh including a metal having a high resistance to corrosion. In some embodiments, the porous container includes at least one of chromium, nickel, aluminum, tin, or alloy. The molten salt bath can include a calcium chloride or a magnesium chloride salt. In some embodiments, the electrical potential includes between about 2V to about 3V.
Separating the graphite deposit from the porous container can include a mechanical separation process. In some embodiments, the mechanical separation process can include rinsing the porous container with deionized or distilled water. The method of producing graphite can further include drying the graphite fragments. In some embodiments, the method of producing graphite can further include capturing volatile components of the coal while beneficiating the amount of coal and applying an electrical potential across the porous container and the graphite anode in the molten salt bath.
A method of producing graphite can include preparing a molten salt bath, adding a crushed coal char and a graphite rod to the molten salt bath, applying an electrical potential between the coal char and the graphite rod, and electrolyzing the molten salt to thermally reduce the coal char to produce an electrochemical graphite deposit. In some embodiments, preparing the molten salt bath includes heating a salt to 800° C. and electrolyzing the molten salt to form a reaction region.
Electrolyzing the molten salt can be continuously performed, in some embodiments. The graphite rod can include a series of graphite rods continuously supplied to reduce the coal char to continuously produce the electrochemical graphite deposit. In some embodiments, the electrical potential can be applied by coupling a conductive container including the coal char to a first wire conveyor and the graphite rod from a second wire conveyor, wherein the first wire conveyor and the second wire conveyor are suspended above the molten salt bath, coupling an electrical tension roller to the first wire conveyor and the second wire conveyor such that the coal char and the graphite rod suspend in the molten salt bath, and applying a voltage to the electrical tension roller such that the coal char is cathodic and the graphite rod is anodic, wherein carbon in the coal char transforms to graphite.
In some embodiments, the method of producing graphite can further include conveying the coal char and the graphite rod through at least a portion of the molten salt bath, removing the graphite rod and the conductive container from the molten salt bath, where the conductive container includes a graphite deposit. The method can further include separating the graphite deposit from the conducive container, and washing the graphite deposit with deionized or distilled water. In some embodiments, the method of producing graphite can further include processing the deionized or distilled water after washing the graphite deposit to capture and recycle salts.
An electrolytic apparatus to produce graphite can include a molten salt bath and an electrical source including a first wire conveyor and a second wire conveyor disposed above the molten salt bath, wherein the electrical source produces a voltage potential between the first wire conveyor and the second wire conveyor. The electrolytic apparatus can also include at least one coal char cathode suspended from the first wire conveyor and at least one graphite anode suspended from the second wire conveyor. The electrolytic apparatus can also include an electrical tension roller contact bus configured to couple to the first wire conveyor and the second wire conveyor. The electrical tension roller contact bus biases the at least one coal char cathode and at least one graphite anode to be suspended within the molten salt bath. The electrolytic apparatus can further include an electrolytic cell formed when the voltage is applied to the at least one coal char cathode and the at least one graphite anode to thermally reduce the coal char to produce an electrochemical graphite deposit. The graphite anode includes a series of graphite rods continuously supplied to reduce the at least one coal char cathode and to form a graphite deposit. In some embodiments, the molten salt bath includes a calcium chloride or a magnesium chloride salt heated to about 800° C. The electrical source can include a DC power supply including a voltage between about 2V and about 3V.
The accompanying drawings illustrate various embodiments of the present apparatus and are a part of the specification. The illustrated embodiments are merely examples of the present apparatus and do not limit the scope thereof.
Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements.
As described below, graphite can be produced from raw, mined coal. In some embodiments, the coal can be beneficiated to form a coal char that can then produce a graphite therefrom. High quality graphite can be produced at a relatively low temperature and low electrical energy using a molten salt process. This process can be scaled to a continuous and high-volume production of graphite.
Reference will now be made in detail to representative embodiments illustrated in the accompanying drawings. It should be understood that the following descriptions are not intended to limit the embodiments to one preferred embodiment. To the contrary, it is intended to cover alternatives, modifications, and equivalents as can be included within the spirit and scope of the described embodiments as defined by the appended claims.
According to some embodiments, and as illustrated in
Act 104 of the method of producing graphite 100 includes adding a crushed coal char to the molten salt bath. In some embodiments, the char can be crushed to increase the surface area of the coal char. In some embodiments, the coal char can be ground to less than 100 microns. In other embodiments, the coal char can be ground to less than 80 microns. In some embodiments, the coal char can be ground to between about 0.5 micron and about 50 microns. For example, the coal char can exhibit a diameter that is about 5 μm or less, about 10 μm or less, about 20 μm or less, about 30 μm or less, about 50 μm or less, about 60 μm or less, about 70 μm or less, or in ranges of about 5 μm to about 15 μm, about 10 μm to about 20 μm, about 15 μm to about 25 μm, about 20 μm to about 30 μm, about 25 μm to about 35 μm, about 30 μm to about 40 μm, about 35 μm to about 45 μm, about 40 μm to about 50 μm, about 45 μm to about 60 μm, about 50 μm to about 70 μm, about 60 μm to about 80 μm, about 70 μm to about 90 μm, or about 80 μm to about 100 μm. Reducing the grind size and increasing the surface area of the char can improve the efficiency of the graphite production. In other words, the finer the ground char, the better the results of the quality and yield of the graphite. In some embodiments, the crushed coal char can be screened or passed through a sieve for sizing. The coal char can be ground or crushed by any suitable means (e.g. jaw crusher, roller, immersion blender, etc.) Act 106 of the method of producing graphite 100 includes adding a graphite rod to the molten salt bath. The graphite rod can be an isomolded or extruded rod. In some embodiments, the graphite rod can include carbon graphite, electrographite, or resin-bonded graphite. The graphite rod can be any suitable shape. In some embodiments, the graphite rod can include a plate or slug.
Act 108 of the method of producing graphite 100 includes applying an electrical potential between the coal char and the graphite rod. The electrical potential can be a direct current (DC) applied potential. The electrical potential can be between 2-3 Volts, in some embodiments. An electrical current can be applied directly to the coal char and/or the graphite rod.
As illustrated in
As shown in
In some examples, the act 302 can include forming a pitch from the coal prior to forming the coal char. As used herein, pitch, also known as coal pitch, coal tar, or coal tar pitch, can refer to a mixture of one or more typically viscoelastic polymers as will be well understood by the skilled artisan. The pitch produced at act 302 can include one or more high molecular weight polymers. In some embodiments, the pitch can have a melting point of greater than about 650° F. In some embodiments, the pitch can have a melting point that is sufficiently high that the pitch can be used in a carbon fiber spinning process, for example, as described herein, without the need for a plasticizer. In some examples, the pitch can be an isotropic pitch. In some examples, the isotropic pitch can be subjected to further processing, such as heating in an inert atmosphere to form or produce mesophase pitch. As used herein, the term mesophase pitch can refer to any pitch that is greater than about 40% mesophase. In some examples, however, the term mesophase pitch can be used to refer to pitch that includes any amount of pitch in a mesophase state.
In some embodiments, the pitch can include aromatic hydrocarbons, for example, polycyclic aromatic hydrocarbons. In some examples, the pitch can include at least about 50 wt. % polycyclic aromatic hydrocarbons, at least about 60 wt. %, 70 wt. %, 80 wt. %, 90 wt. %, 95 wt. %, or 99 wt. % or greater of polycyclic aromatic hydrocarbons. In some embodiments, the pitch can be relatively free of impurities, such as water, non-carbon atoms including sulfur or nitrogen, or material such as coal ash or char. In some examples, the pitch can include less than about 0.2 wt. % water, less than about 0.1 wt. %, less than about 0.05 wt. %, or less than about 0.01 wt. % water or lower. In some examples, the pitch can include less than about 0.1 wt. % ash or other solid material, less than about 0.05 wt. % ash or solid material, or less than about 0.01 wt. % ash or solid material. In some examples, the pitch can have a flash point greater than about 230° F., greater than about 250° F., or greater than about 300° F. In some examples, the pitch can have an API gravity of less than about 4, less than about 3, or less than about 2, or less. In some embodiments, the pitch can have a hydrogen to carbon (H:C) ratio of less than about 1, less than about 0.8, less than about 0.5, less than about 0.2, less than about 0.1, or lower. In some embodiments, the pitch can be an isotropic pitch.
In some examples, the conversion of coal to pitch in act 302 can remove impurities from the coal. In some embodiments, the pitch can be relatively free of impurities, such as water, non-carbon atoms including sulfur or nitrogen, or material such as coal ash or char. In some examples, the pitch can include less than about 0.2 wt. % water, less than about 0.1 wt. %, less than about 0.05 wt. %, or less than about 0.01 wt. % water or lower. In some examples, the pitch can include less than about 0.1 wt. % ash or other solid material, less than about 0.05 wt. % ash or solid material, or less than about 0.01 wt. % ash or solid material. In an example, a system that converts the coal to pitch prior to making graphite can result in an iron impurity of greater than 1500 ppm. When the coal is first converted to a pitch prior to forming graphite, the iron impurity can be less than about 50 ppm.
In some embodiments, during beneficiating, an act 304 of capturing volatiles can be included. In some embodiments, the coal utilized by the processes described herein can be lignite coal, and can have a volatile content of greater than about 45 wt. %. In some embodiments, the coal can be sub-bituminous coal, bituminous coal, and/or anthracite coal. In some embodiments, the raw coal can be beneficiated to remove contaminants or impurities such as water and/or heavy metals. In some embodiments, beneficiating the coal can produce various other products that can be captured and used in later processing steps, that can be valuable in and of themselves, or that can be subjected to further processing or use in the method 300. That is, in some embodiments, beneficiating the coal can produce or separate gases or liquids from the raw coal. These gases and/or liquids can be captured or separated during processing. For example, beneficiating the coal at act 302 can produce H2, CO2, CO, CH4, C2H4, C3H6, and/or other hydrocarbon gases, which can be captured and subsequently utilized in act 304 or in other process steps. In some cases, beneficiating the coal can result in liquids such as C2, C3, and/or C4 hydrocarbons, toluene, and/or benzene, which can be captured for subsequent use or processing.
Acts 304 and 304 of the method 300 are for illustrative purposes and can be modified. For example, the acts 302 and 304 can be performed in different orders, split into multiple acts, modified, supplemented, or combined. In an example, one or more of the acts 302 or 304 of the method 300 can be omitted from the method 300. Any of the acts of method 300 can include using any of the assemblies or systems disclosed herein.
In some cases, beneficiation can include heating an amount of coal to one or more temperatures for a desired duration. In some other embodiments, the coal can be beneficiated by heating the coal to a desired temperature in the presence of one or more catalyst compounds. In some cases, beneficiating the coal can include pyrolyzing the coal, for example in the presence of a catalyst. In some embodiments, beneficiation can include heating the amount of coal in an indirectly heated rotary kiln. The kiln can be heated by natural gas or electrical heat. In some embodiments, the rotary kiln can be heated to a temperature between about 600° C. to about 1000° C.
The method 300 can include an act 306 that includes grinding the coal char to produce a crushed char. In some embodiments, the char can be crushed to increase the surface area of the coal char. In some embodiments, the coal char can be ground to less than 100 microns. In other embodiments, the coal char can be ground to less than 50 microns. In some embodiments, the coal char can be ground to about 350 mesh or less. In some embodiments, the crushed coal char can be screened. The coal char can be ground or crushed by any suitable means (e.g. jaw crusher, roller, immersion blender, etc.). The crushed char can be ground to a powder in some examples. The powder can be liquified or formed into a paste in some examples, as explained in greater detail below.
The method 300 can include an act 308 that includes placing the crushed char in a porous container. In some embodiments, the porous container includes a mesh metal container. The mesh metal container can include a metal having a high resistance to corrosion. In some embodiments, the porous container can include at least one of a passive metal. The porous container can include at least one of chromium, nickel, aluminum, tin, or a passive alloy. The porous container can be any suitable container that can be resistant to molten salt and/or high temperature conditions and include pores and/or apertures.
In some examples the act 308 can include spreading the crushed char or powder onto a plane or a roller unit. In other words, the porous container can include a permeable substrate or material in which the crushed char can be placed as a thin layer. For example, the crushed char can be spread in a thin layer on a porous or non-porous sheet configured to be immersed in a molten salt bath. The term “roller unit” means a roll-to-roll apparatus including one or more rollers. In this example, the shape and/or a size and/or arrangement of rollers are not limited and can be varied according to various examples. A char/graphite roll-to-roll transfer method in accordance with one aspect of the present disclosure includes forming a layered structure including substrate-char layer-first flexible substrate from a char layer formed on a substrate and a first flexible substrate in contact with the char layer by a first roller unit; and immersing the layer in a salt bath solution and passing the layer through the bath by using a second roller unit to remove the substrate from the layered structure and to transferring the graphite or char layer onto the first flexible substrate at the same time. In an illustrative embodiment, the graphite roll-to-roll transfer method can further include, but is not limited to, transferring the graphite layer on the first flexible substrate onto a second flexible substrate by a third roller unit. In some examples the act 308 includes simply applying a thin layer of the crushed char or powder onto a permeable substrate material and passing the substrate material through a molten salt bath. Various automated, manual, or hybrid systems and methods can be used to transport the thin layer of the crushed char or powder through the molten salt bath for the production of graphite.
The method 300 can include an act 310 that includes immersing the porous container in a molten salt bath. In an example, the porous container can be immersed near the surface of the molten salt bath. For example, the container can be immersed less than 1 meter from the surface, less than 0.5 meters, less than 100 cm, less than 50 cm, less than 10 cm, or less than 5 cm from the surface of the molten salt bath.
In some embodiments, the molten salt bath includes a calcium chloride salt. In other embodiments, the molten salt bath can include a magnesium chloride salt. Any suitable salt or combination of salts can be included. The molten salt can be heated to about 800° C. in some embodiments. The molten salt bath can include a graphite anode. In some embodiments, the graphite anode can include an incomparable balance of relatively low cost, abundance, high energy density, power density, and very long cycle life. Further, Graphite anodes meet the voltage requirements of the crushed char as a cathode and is porous and durable. In some examples, the method 300 can include more than one graphite anode and, similarly, more than one cathode. The inclusion of multiple anodes and cathodes in the molten salt bath can allow for greater efficiency of the method 300. For example, the configuration can include a bath system that can produced graphite in greater quantities than when compared to a single anode or single cathode system. For example, graphite can be produced up to 10 kilograms, up to 50 kilograms, or up to 100 kilograms per bath. In some examples, the method 300 can produce up to 200 kg, up to 500 kg, or up to 800 kg per bath.
The method 300 can also include an act 312 that includes applying an electrical potential across the porous container and the graphite anode such that a graphite deposit forms from the char. The mechanism for the deposit is describe above in reference to
In some embodiments, the act 312 of applying an electrical potential across the porous container and the graphite anode can be continuously performed. In such a continuous process, electrolyzing the molten salt can be continuous. The graphite anode or graphite rod can include a series of graphite rods continuously supplied to reduce the coal char to continuously produce the graphite deposit on the graphite anode. As a continuous process, the electrical potential can be applied by coupling the porous container including the coal char to a first wire conveyor and the graphite collector rod from a second wire conveyor. In some embodiments, the first wire conveyor and the second wire conveyor are suspended above the molten salt bath. The act 312 can further include coupling an electrical tension roller to the first wire conveyor and the second wire conveyor such that the coal char and the graphite collector rod suspend in the molten salt bath. Then a voltage can be applied to the electrical tension roller such that the coal char is cathodic and the graphite collector rod is anodic. Carbon then converts to graphite. In some embodiments, the coal char and the graphite rod can be conveyed through at least a portion of the molten salt bath. In some embodiments, the first wire conveyor and the second wire conveyor are coupled to a system that passes the coal char and the graphite collector rod through the molten salt bath in a counter current direction. For example, the porous container including the coal char can be conveyed through the molten salt bath in a first direction from a first end of the bath to a second end of the bath where the coal char is then removed from the molten salt bath. The graphite rod(s) are conveyed through the molten salt bath in a second direction opposite the first direction from the second end of the bath to the first end of the bath where the graphite rod(s) are then removed from the molten salt bath.
The method 300 can include an act 314 that includes removing the graphite anode from the molten salt bath. In an example having multiple anodes, each graphite anode can be removed from the molten salt bath. In a roll-to-roll process, the graphite layer can be removed from the molten salt bath either via a roll or extraction process to remove the graphite sheet from the permeable substrate. The act 314 can include a continuous process in some examples, or non-continuous roll-to-roll processes, as described in greater detail below. In act 314, the graphite anode includes graphite deposit. In some embodiments, the graphite anode further includes salt deposits from the molten salt bath. On each side of the bath, the char container or graphite rod leaves the bath to be recovered and/or recycled. The graphite anode rods are moved slowly, based on the rate of deterioration of the rods in the salt bath. As the graphite anode is removed from the molten salt, the graphite anode can be cooled below the freezing temperature of the salt. In some embodiments, the graphite anode can be air cooled by either contact with air or by convection. In other embodiments, the graphite anode can be cooled in an inert atmosphere. The graphite anode can be further cooled by washing with a deionized and/or distilled water. The deionized and/or distilled water can be sprayed on the graphite anode or can be a separate cooling bath that the graphite anode can be dipped in. The salt can be removed from the graphite anode and collected and/or reprocessed and recycled for use in the molten salt bath of act 310. The reprocess and/or recycling of the salt can be performed by any suitable means. In some embodiments, the deionized and/or distilled water can be processed in a reverse osmosis system. In other embodiments, the salt can be concentrated, dried, or distilled from the water that was used to wash the graphite anode.
The method 300 can include an act 316 that includes removing the graphite deposit from the container to produce graphite fragments. In some embodiments, the separating includes a mechanical separation process. The graphite fragments of act 316 can be scraped off and collected robotically, as the container is at a high temperature. In some embodiments, the container can be cooled through an enclosed conveyor portion that cools the container and the graphite deposit therein. In some embodiments, the container can be vibrated and/or impacted to remove the graphite fragments. In other embodiments, any suitable mechanical or chemical separation process can remove the graphite deposit. In some embodiments, the mechanical separation process includes washing and/or rinsing the container with deionized or distilled water. The deionized and/or distilled water can be sprayed on the container or can be a separate bath that the container can be dipped in. In some examples, the graphite can form on other parts of the system. For example, the graphite fragments can be collected from the graphite anode rods or can be free floating in the salt bath. The graphite can be collected with a mechanical filter from the salt bath and scraped off of the graphite rods. In some examples, the salt bath can be cooled and the graphite can be collected from the surface of the bath. In some examples, the process can be shut down to cool the bath and collect the graphite from the surface when a predetermined amount of graphite is collected at the surface. For example, when a predetermined thickness (e.g., 1 cm) of graphite layer is collected at the surface of the bath.
The method 300 can include an act 318 that includes drying the graphite fragments. The graphite fragments can be dried by any suitable method. In some embodiments, the graphite fragments can be dried in a rotary kiln, an oven, forced air, or allowed to dry at ambient temperature. In some embodiments, the graphite fragments can then be check for quality control and packaged for distribution.
Referring now to
The electrolytic apparatus 400 can further include an electrical source 404. The electrical source 404 can include a DC power source capable of producing a voltage (V) between about 1 volt and about 10 volts. The electrical source can include any suitable power source capable of maintaining a constant DC voltage. In some embodiments, the electrical source 404 can include a first wire conveyor 406 and a second wire conveyor 408 disposed above the molten salt bath 402. The electrical source 404 can be configured to produce a voltage potential between the first wire conveyor 406 and the second wire conveyor 408. In some embodiments, the voltage potential between the first wire conveyor 406 and the second wire conveyor 408 can be between about 2V and about 3V.
The electrolytic apparatus 400 can further include at least one coal char cathode 410 suspended from the first wire conveyor 406. In some embodiments, the coal char cathode 410 can include a char basket 412. In other examples, the char cathode 410 can include a thin layer of char on a permeable substrate. The char basket 412 or substrate can be configured to hold a crushed coal char. The crushed coal char can include the at least one coal char cathode 410. The char basket 412 can include a mesh metal container or a permeable or non-permeable plane that can be submersed in the molten salt bath. The char basket 412 or plane can include a metal having a high resistance to corrosion. In some embodiments, the char basket 412 or plane can include at least one of a passive metal. The char basket or plane 412 can include at least one of chromium, nickel, aluminum, tin, or a passive alloy. The char basket or plane 412 can be any suitable container that can be resistant to molten salt and/or high temperature conditions and include pores and/or apertures.
The electrolytic apparatus 400 can further include at least one graphite anode 414 suspended from the second wire conveyor 408. In some examples, the graphite anode is not suspended, but the graphite anode can include a thin layer or sheet disposed on a substrate configured to be immersed in the molten salt bath. The sheet and/or substrate can be configured in a roll-to-roll system. In some embodiments, the graphite anode 414 can be any suitable graphite body. The graphite anode 414 can be an isomolded or extruded rod. In some embodiments, the graphite anode 414 can include carbon graphite, electrographite, or resin-bonded graphite. The graphite anode 414 can be any suitable shape. In some embodiments, the graphite anode 414 can be a graphite rod, a plate, or a slug.
The electrolytic apparatus 400 can further include an electrical tension roller contact bus 416. The electrical tension roller contact bus 416 can be configured to couple to the first conveyor 406 and the second conveyor 408. The electrical tension roller contact bus 416 can include a cathode portion 416A and an anode portion 416B. The cathode portion 416A can be configured to contact the first conveyor 406 and the anode portion 416B can be configured to contact the second conveyor 408. In some embodiments, the electrical tension roller contact bus 416 can bias the at least one coal char cathode 410 and the at least one graphite anode 414 to be suspended within the molten salt bath 402. In some embodiments, the first conveyor 406 and the second conveyor 408 are supported by above the molten salt bath 402 by offset wire supports 418. The offset wire supports 418 can maintain tension in the first conveyor 406 and the second conveyor 408. The offset wire supports 418 can further include a motor and/or be coupled to an external motor (not shown) to rotate the first conveyor 406 and the second conveyor 408 continuously or periodically. In some examples, the first conveyor 406 and the second conveyor 408 are not supported by the wire supports 418 but are configured as a roll-to-roll system.
Thus, the electrolytic apparatus 400 forms an electrolytic cell to produce graphite through an oxidation reaction on the graphite anode 414. In some embodiments and electrolytic cell is formed continuously as the voltage is applied to the at least one coal char cathode 410 and the at least one graphite anode 414. The electrolytic cell can be configured to thermally reduce the coal char cathode 410 to produce an electrochemical graphite deposit 420 from the coal char. As shown in
In some embodiments, once the graphite deposit 420 is separated from the char basket or substrate 412, the graphite deposit 420 can be cooled by conveying the graphite deposit 420 in air or in an inert environment and then can be washed with deionized and/or distilled water. In some embodiments, the washing can remove residual salts from the graphite deposit 420. The cooled and washed graphite deposit 420 can then be dried by any suitable means, inspected for quality control, and packed as described above. In some embodiments, the rinse water is sent to a recovery system for recycling the solid salt and make it available for reuse in the molten salt bath 402. The deionized and/or distilled water can be processed in a reverse osmosis system to recover the salts.
Unless otherwise indicated, all numbers or expressions, such as those expressing dimensions, physical characteristics, etc., used in the specification (other than the claims) are understood as modified in all instances by the term “approximately.” At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the claims, each numerical parameter recited in the specification or claims which is modified by the term “approximately” should at least be construed in light of the number of recited significant digits and by applying ordinary rounding techniques.
In addition, all ranges disclosed herein are to be understood to encompass and provide support for claims that recite any and all subranges or any and all individual values subsumed therein. For example, a stated range of 1 to 10 should be considered to include and provide support for claims that recite any and all subranges or individual values that are between and/or inclusive of the minimum value of 1 and the maximum value of 10; that is, all subranges beginning with a minimum value of 1 or more and ending with a maximum value of 10 or less (e.g., 5.5 to 10, 2.34 to 3.56, and so forth) or any values from 1 to 10 (e.g., 3, 5.8, 9.9994, and so forth).
The foregoing description, for purposes of explanation, used specific nomenclature to provide a thorough understanding of the described embodiments. However, it will be apparent to one skilled in the art that the specific details are not required in order to practice the described embodiments. Thus, the foregoing descriptions of the specific embodiments described herein are presented for purposes of illustration and description. They are not target to be exhaustive or to limit the embodiments to the precise forms disclosed. It will be apparent to one of ordinary skill in the art that many modifications and variations are possible in view of the above teachings.
This application claims priority to U.S. Provisional Application No. 63/512,878, filed 10 Jul. 2023, entitled METHODS AND APPARATUS FOR PRODUCTION OF ELECTROCHEMICAL GRAPHITE, and to U.S. Provisional Application No. 63/518,479, filed 9 Aug. 2023, entitled METHODS AND APPARATUS FOR PRODUCTION OF ELECTROCHEMICAL GRAPHITE, the disclosures of each of which are incorporated herein by reference in their entireties.
| Number | Date | Country | |
|---|---|---|---|
| 63512878 | Jul 2023 | US | |
| 63518479 | Aug 2023 | US |
