Joule heating of a mixed powder

Abstract

The embodiments disclosed herein relate to methods and systems for efficient Joule heating of powder materials, and in particular, Joule heating of a powder feedstock that is mixed while the powder is Joule heated. The methods and systems apply to powder materials comprising carbon, silicon-material powders, and plastic powders. The Joule heating of this invention can control the degree of carbon graphitization, the degree of silicon-material crystallization, and the carbonization of plastics and polymers.

Description

Joule Heating of a Mixed PowderTechnical Field

[0001] The embodiments disclosed herein relate to methods and systems for efficient Joule heating of powder materials, and in particular, Joule heating of a powder feedstock, comprising carbon, silicon-material, and plastic, that is mixed while the powder is Joule heated.Background of the Invention

[0002] The term "graphene" refers to a material which is a one-atom-thick planar sheet of sp2-bonded carbon atoms that are densely packed in a honeycomb crystal lattice, and, further, contains an intact ring structure of carbon atoms and aromatic bonds throughout at least a majority of the interior sheet and lacks significant oxidation modification of the carbon atoms. Graphene has a predominantly crystalline structure and its quality is measured by its degree of crystallinity. The term "a graphene monolayer" refers to graphene that is a single layer of graphene. The term "very few layer graphene" refers to graphene that is between 1 to 3 layers of graphene. The term "few layer graphene" refers to graphene that is between 2 to 5 layers of graphene. The term "multilayer graphene" refers to graphene that is between 2 to 10 layers of graphene. Monolayer to multilayer graphene has typical lateral sizes from sub-lOOnm to few microns. The term "graphite" refers to a structure that has more than 10 layers of graphene. Graphite has typical lateral sizes from 10s of nanometers to 10s of microns.

[0003] "Graphite" refers to a carbon structure that has more than 10 layers of graphene in an ordered stacking arrangement. Graphite may have AB, also known as Bernal, or ABC, also known as rhombohedral, stacking arrangement.

[0004] A flash Joule heating synthesis of graphene is disclosed by Luong et al. (Nature 577, 647-651, 2020) and the related patent application by Tour et al. (WO 2020 / 051000), where electrically conductive amorphous carbon material is resistively heated to convert the carbon into graphene. In this prior art disclosure, carbon material is compressed into a quartz tube, sealed with two electrode plugs, and 1 to 100 voltage pulses are applied from 1 ms to 5 seconds each to rapidly heat the confined carbon and convert it into turbostratic graphene. The carbonmaterial of this prior art disclosure includes conductive carbon source materials, such as coke, petroleum coke, biomass, among others, and conductive carbon additive, such as anthracite coal, calcined petroleum coke, shungite, carbon nanotubes, acetylene black, and carbon black. The limitation of this prior art disclosure is that does not teach how to make graphite from carbon sources.

[0005] The prior art process flow diagram of the disclosure by Luong etal. shown in Figure 1A requires that the carbon source is compressed and that voltage pulses are applied to a static (not mixed) material, resulting in some of the carbon material, where the current path is stronger, being converted into graphene, and where the process could be repeated until a desired portion of carbon material is converted to graphene. However, unless the material from the first batch is mixed and repacked, which is not disclosed in this prior art, the electrical current will tend to flow through the same fraction of the material that was already been Joule heated, thus leaving unconverted carbon in the batch. An additional limitation of this prior art disclosure is that the one-plus Joule heating step may require higher current, that requires larger power equipment, because the graphene resistance along the primary current path is lower (which is not good for efficient Joule heating) than the carbon resistance.

[0006] A flash Joule heating synthesis of graphite from anthracite coal carbon source is disclosed by Shu et al. (ACS Applied Energy Materials Article ASAP, DOI: 10.1021 / acsaem.3c02975). In this prior art disclosure the anthracite coal grains were compressed into a quartz tube reactor with two electrodes and the coal was flash Joule heated 5 times for 0.1 seconds to convert the anthracite coal grains into turbostratic graphite. Each flash heating step converted more amorphous carbon into graphite and increased the thickness of the graphitized layers. The limitation of this prior art disclosure is that it does not teach how to make graphite from other carbon sources and how to make graphite efficiently since it requires multiple discontinuous Joule heating events.

[0007] The prior art process flow diagram of the disclosure by Shu et al. shown in Figure IB requires that the anthracite coal powder is compressed in a quartz tube reactor, and that current pulse is applied to a static (not mixed) material, resulting in some of the coal, where the current path is stronger, to being converted into graphite, and where the process could berepeated until a desired portion of the coal is converted to graphite. This prior art disclosure also does not teach mixing and repacking a previous batch (having both graphite and unprocessed coal) before a new Joule heating process is applied again. Unless the material from the first batch is mixed and repacked, which is not disclosed in this prior art, the electrical current will tend to flow through the same fraction of the material that was already Joule heated, thus leaving unconverted coal in the batch. An additional limitation of this disclosure is that the one-plus Joule heating step may require higher current, that requires larger power equipment, because the graphite resistance along the primary current path is lower (which is not good for efficient Joule heating) than the coal resistance.

[0008] The principle of the Joule heating process is to resistively heat (Joule heat) an electrically conductive material with electrical power to induce rapid and efficient self-heating that converts the material to a different state. Prior art (Luong et al.) discloses how carbon material is converted from amorphous carbon to graphene, wherein the electrical power is applied to a static carbon powder that remains static (the carbon powder does not mix or move within the reactor) until the Joule heating process is completed. Other prior art (Shu et al.) discloses synthesis of graphite from anthracite coal, wherein the electrical power is applied to a static coal material that remains static (the coal powder does not mix or move within the reactor) until the Joule heating process is completed. Both prior art processes produce non-uniform material conversion, are not as efficient, and do not provide control over the degree of material conversion, and are limited to carbon based materials. Embodiments of the present invention resolve the limitations of the prior art.Summary Of The Invention

[0009] The current invention comprises efficient Joule heating of powder materials, and in particular, efficient Joule heating of a powder feedstock, comprising carbon, silicon-material, and / or plastic, that is mixed while the powder is Joule heated.

[0010] One exemplary embodiment of the current invention is a method comprising Joule heating a powder feedstock material in a reactor, and mixing the powder feedstock material while Joule heating, wherein mixing the powder comprises moving the powder grains withrespect to each other or to their absolute position within the reactor, wherein the mixing can be continuous or intermittent.

[0011] Another exemplary embodiment of the current invention is the referenced method wherein the powder feedstock material comprises carbon. Another exemplary embodiment of the current invention is the referenced method wherein the powder feedstock material comprises carbon and a silicon material. Another exemplary embodiment of the current invention is the referenced method wherein the powder feedstock material comprises carbon and plastic. Another exemplary embodiment of the current invention is the referenced method wherein the powder feedstock material comprises carbon, silicon material, and plastic.

[0012] Another exemplary embodiment of the current invention is a method of Joule heating a powder feedstock material comprising electrically conductive plastic char in a reactor, mixing the powder feedstock material while Joule heating, adding additional plastic powder feedstock during the Joule heating and mixing, converting the plastic powder feedstock into plastic char and at least hydrogen gas, collecting the hydrogen gas, removing some of the plastic char from the reactor, and adding more plastic powder feedstock such that the process is continuous.

[0013] Another exemplary embodiment of the current invention is a method comprising Joule heating a powder feedstock material in a reactor, wherein the powder feedstock material comprises carbon and plastic, at least some of the plastic is carbonized into amorphous carbon, and at least some of the powderfeedstock material is coated by a layer of the amorphous carbon.Brief Description of the Drawings

[0014] The drawings included herewith are for illustrating various examples of articles, methods, and systems of the present specification. In the drawings:

[0015] FIG. 1A - shows the prior art process for graphene synthesis via Joule heating.

[0016] FIG. IB - shows the prior art process for graphite synthesis via Joule heating.

[0017] FIG. 2 - shows the process for carbon feedstock graphitization via Joule heating and with mixing.

[0018] FIG. 3 - shows the process for carbon graphitization via Joule heating with carbon fines elimination.

[0019] FIG. 4 - shows the process for carbon graphitization via Joule heating with carbon fines sieving.

[0020] FIG. 5 - shows the process for carbon and silicon material feedstock crystallinity increase via Joule heating and mixing.

[0021] FIG. 6 - shows the process for carbon and plastic feedstock conversion via Joule heating and with mixing.

[0022] FIG. 7 - shows the process for carbon, silicon material, and plastic feedstock conversion via Joule heating and with mixing.

[0023] FIG. 8 - shows an illustration of exemplary XRD peaks of carbon material with different levels of graphitization.

[0024] FIG. 9 - shows the XRD peaks of an exemplary fully graphitized carbon (graphite) material produced by the methods of this inventionDetailed Description

[0025] Various systems or processes will be described below to provide an example of each claimed embodiment. No embodiment described below limits any claimed embodiment and any claimed embodiment may cover processes or systems that differ from those described below. The claimed embodiments are not limited to systems or processes having all of the features of any one system or process described below or to features common to multiple or all of the systems described below.

[0026] Embodiments of the present invention resolve the limitations of the prior art and offer solutions that make possible to synthesize and produce graphite material with Joule heating from a variety of carbon containing materials, which is efficient and that includes mixing of the carbon containing material within a reactor as it undergoes Joule heating. Furthermore, the present invention offers solutions to efficiently increase (improve) the crystallinity (the crystal structure) of a material, for example carbon or silicon, with Joule heating with a precise controlover the degree of crystallinity improvements. Although the degree of crystallinity improvements in a material is continuous, for the purposes of describing this invention the degree of crystallinity improvements may be qualitatively described as partial, substantial, and full material crystallization. Additionally, the present invention offers an efficient Joule heating based solutions to convert plastics, and polymers in general, into amorphous carbon (plastics char) that can be further converted into carbon with any degree of crystallinity.

[0027] The conversion of a carbon material into more crystalline carbon material is known as graphitization. Carbon graphitization refers to the process of heating a carbon material to high temperatures, causing its carbon atoms to rearrange into a more ordered, crystalline structure, thus enhancing its crystalline level. The degree of graphitization of a material is continuous, but may be described as partial, substantial, and full carbon graphitization for ease of reference. One manifestation of full carbon graphitization is graphite. When the carbon feedstock used to synthesize the graphite is not from mined or natural mineral then the graphite is referred to as synthetic graphite.

[0028] The conversion of a silicon-based material into more crystalline form of the silicon material refers to the process of enhancing the ordered, crystalline structure within a silicon material, where silicon atoms are arranged in a consistent lattice pattern. The term silicon material refers to silicon, silica, or any silicon compound.

[0029] A polymer is a chemical compound made of repeating units called monomers, while plastic is a specific type of polymer. Plastic is a synthetic or semi-synthetic material made from polymers and has carbon, hydrogen, and depending on the plastics oxygen, nitrogen, and other molecules. When plastic or polymer undergo a thermal decomposition, the volatile components like hydrogen and oxygen are released as gases during the heating process, eventually leaving behind a carbon-rich residue, called char, although not always pure carbon depending on the plastic and the decomposition conditions. This invention will describe the innovative exemplary methods and systems with plastics as an example, but the innovation equally applies to polymers.

[0030] The conversion (thermal decomposition) of polymers or plastics into carbon chars is also known as carbonization or pyrolysis. Carbonization is a thermal decomposition process by which an organic compound, like polymer or plastics, are heated to remove volatile compound and result in a mostly carbon-based material, the char, that is typically an amorphous carbon material.

[0031] Embodiments of the present invention describe the advantages of Joule heating based method for more rapid and efficient material crystallization, which can include carbon graphitization, and silicon material crystallization increase, as well as conversion of plastics into amorphous carbon, that are faster and more energy efficient than conventional methods. In some embodiments, conventional carbon graphitization to graphite may take days while Joule heating based carbon graphitization takes minutes to complete. Similarly, the formation of silicon carbide from carbon and silica is days long process, while the Joule heating based conversion takes minutes to complete. Similarly, the carbonization of plastics in a rotary oven is hours long process, while the Joule heating based carbon carbonization takes minutes to complete.

[0032] The degree of crystallization for carbon and silicon materials can be analytically measured with instruments like Raman spectroscopy or X-ray diffraction (XRD). In general, carbon material has Raman peaks that are known as D and G bands and are broad for amorphous carbon and narrow for crystalline carbon materials. In Raman spectroscopy of carbon materials, specific D, G, and 2D peaks represent different vibrational modes within the carbon structure, with the intensity and shape of these peaks providing information about the degree of graphitization, meaning how well-ordered carbon atoms are arranged in a graphitic lattice. Higher intensity D peak relative to the G peak indicates a greater presence of defects and less graphitization, while a strong and sharp 2D peak suggests a high degree of graphitic order. Similarly, in an XRD measurement, an amorphous carbon has a broad XRD peak observed at a specific 20 angle, known as (002) peak, which correlates to the interplanar spacing between the stacked graphitic layers in a carbon structure, essentially indicating the degree of graphitization, wherein a higher intensity and sharper (002) peak generally signifies a more ordered graphiticstructure. A person skilled in the art would be able to determine therefore whether graphitization of a carbon sample is partial, substantial, or full.

[0033] Figure 8, published by Zhang et al. (Energy Fuels 2024, 38, 18, 17370-17379), shows the XRD peaks of carbon material with different levels of graphitization (partial, substantial, or full) as a function of the process temperature for a prior art graphitization process. These results utilize classical thermal methods of carbon graphitization, that are longer and less efficient, than the graphitization by Joule heating and feedstock mixing of this invention, but the resulting XRD measurement of the carbon graphitization are applicable. This figure demonstrates exemplary methods of distinguishing between partial, substantial, and full graphitization. In this particular example, the XRD spectra at temperature levels of approximately 1400 C - 2200 C would be considered partial, at temperature levels of 2300 C - 2600 C would be considered substantial, and at temperature level 2700 C - 2900 C would be considered full graphitization. The spectra of the graph below the temperature level of 1400 C could be considered amorphous carbon.

[0034] Similarly, the level of silicon structure crystallization can be measured with instruments like X-ray diffraction (XRD) and Raman spectroscopy. In general, the higher the degree of crystallization, sharper and more distinct the XRD or the Raman peaks are. The actual position of the XRD and Raman peaks is different for silicon, silica, or silicon carbide. A person skilled in the art would be able to determine therefore whether crystallization of a silicon sample is partial, substantial, or full. Figure 8 demonstrates an exemplary method that can be used to distinguish between partial, substantial, or full crystallization (same method, but different specific spectra, relevant to silicon).

[0035] One advantage of some embodiments of the present invention is the process of mixing the material powder (the feedstock) while it is Joule heated. The overall feedstock volume that will be Joule heated needs to be electrically conductive but not every grain of the powder that comprises the feedstock needs to be electrically conductive. The term mixing (and moving) the powder material is defined as moving the grains of the feedstock powder (whether they are electrically conductive or not) inside a process reactor as to make a more uniform volume of powder, before, during, and / or after the Joule heating. Mixing the powder means that grainscomprising the powder are moved with respect to each other to randomize their relative position with respect to each other, or their absolute position within the reactor. The result of mixing the feedstock powder in the reactor so as to average the exposure of energy on the feedstock and to do it more uniformly, resulting in more controllable conversion of the material. In a Joule heating process of prior art the electrical currents flow and the resulting Joule heating is concentrated on a few conductive paths through the feedstock where the same powder grains along the electrically conductive path are repeatedly heated and other powder grains are not, creating non- uniform material conversion and not a good control over the average crystallization of the material. The powder mixing can be conducted continuously during the flash process or intermittently after some energy is delivered. One measure of verifying the product uniformity due to mixing is the Raman signature, for example the consistency of the Raman D, G, and 2D peaks as function of the volume of the material inside a reactor.

[0036] Figure 2 illustrates the process flow diagram of one exemplary embodiment of the present invention that enables efficient flash Joule graphitization of carbon containing powder by applying the Joule heating to the powder while the powder grains are mixed or moved within the reactor so as to average their residency in different locations of the reactor and to average the energy dose delivered to the powder. This process can remove non-uniformities that may exist in the electrical current flow path through a powdered media. The result is a more uniform and efficient conversion of carbon to graphite via Joule heating. The principle of the Joule heating process requires that the feedstock is an electrically conductive material that can conduct electrical current. One measure of electrical conductivity used in these embodiments is the material resistivity (Qxcm), which is the bulk material resistance (Q) normalized over the geometry (length and cross sectional area) of the measured volume of a material. It is preferred that the feedstock has electrical resistivity of less than 1000 Qxcm. Higher material resistivities are possible but the applied voltages have to be higher than 480 V. Different embodiments of this process may include more orfewer of these steps, and embodiments may comprise different steps.

[0037] In Step 1, a reactor (of any shape or form suitable for Joule heating) is filled with powdered material comprising carbon wherein the average material volume is electricallyconductive. A moderate powder compression where the powder can still be mixed is optional but not needed for this process. A reactor, as referenced in this invention and known in the referenced exemplary art, is an apparatus that is capable of containing a volume of electrically conductive powder that can be Joule heated. The reactor also may allow inclusion of a variety of electrode arrangements that are needed to apply power to the electrically conductive powder. The reactor, as modified in this invention also may allow inclusion of apparatuses to mix the powder while the powder is Joule heated, including, for example, using an electrode for mixing. The reactor of this invention also may allow inclusion of apparatuses to remove solid (for example wax), liquid (for example oil) or gas (for example hydrogen, CO, methane, syngas) byproducts from the reactor while the powder is Joule heated.

[0038] In Step 2, an electrical power (kW or MW) is applied to the powder while the powder is mixed or moved in the reactor. Typically, a voltage source of 110 V to 480 V of a Joule heating system is practical. The voltage source can be AC or DC or a combination thereof. Optionally, the mixing may be done with an apparatus external to the reactor or an apparatus that is integrated with the reactor. External powder mixing equipment is well known in the art of powder moving and can be implemented here. Heat resistant material for mixing powder is already readily available in the powder mixing industry. An integrated powder mixing apparatus and method that is capable of mixing powder while Joule heating is applied to the powder, wherein, in one exemplary embodiment, the apparatus comprises of a bucket shaped reactor wherein one of the electrodes mixes the powder within the reactor, is described in Provisional Patent Application US 18 / 484,446, HYDROCARBON PYROLYSIS VIA JOULE HEATING OF POWDER, by Mancevski, having an application date of October 11, 2023, which is herein incorporated by reference in its entirety, and in Provisional Patent Application US 18 / 488,562, INDIRECT HYDROCARBON PYROLYSIS WITH JOULE HEATING OF POWDER, by Mancevski, having an application date of October 17, 2023, which is herein incorporated by reference in its entirety.

[0039] Mixing non-compressed powder is easier than mixing a compressed powder due to the volume constraints, however mechanisms that apply powder compression while the powder is mixed are possible. The powder mixing can be continuous or intermittent. Optionally, electrical power may be applied continuously or with breaks. Optionally, the electrical powerlevel may be controlled to fit the heating profile of the process. Optionally, the powder mixing and the electrical power sub steps may be synchronized to improve efficiency.

[0040] In Step 3, the application of electrical power to the powder having an electrical resistivity, results in localized Joule heating that converts the carbon from the powdered material into graphitized carbon until mixing exposes all or most of the powder to Joule heating and to graphitization conversion. The particular localized heating profile (and temperature profile) depends on the reactor and electrode geometry and designs. In a prior art quartz tube reactor with cylindrical electrode plugs, the powder temperature will be highest at the center of the quartz tube and less hot closer to the inner quartz walls, thus resulting in a non-uniform carbon conversion. In one example (see Mancevski 18 / 484,446), the powder inside a reactor may be mixed during the Joule heating wherein the carbon from the tube walls would be brought into the center of the tube and therefore being exposed to higher temperature that would lead to more uniform graphitization.

[0041] In one embodiment of the invention, carbon graphitization may be partial, substantial, and full. One manifestation of full carbon graphitization is graphite. Partial carbonization, typically occurring in a temperature range from 1400 - 2200 C, means that carbon atoms have started to rearrange into a more ordered, crystalline structure, and have increased crystalline level, as it can be verified by Raman orXRD measurements. Substantial carbonization, typically occurring in a temperature range from 2300 - 2600 C, means that many carbon atoms have formed ordered crystalline structure, but the crystalline structure is not fully ordered, as it can be verified by Raman or XRD measurements. Full carbon graphitization, typically occurring in a temperature range above 2600 C, is the formation of graphite, where most carbon atoms have formed ordered crystalline structure, and the crystalline structure is fully ordered. In one measurement example, the Raman or XRD peaks of partial, substantial, and fully graphitized carbon would be narrowing, and their respective Full Width Half Maximum (FWHM) of the peaks would get narrower. Figure 9 shows the XRD peaks of an exemplary fully graphitized carbon (graphite) material produced by the methods of this invention using PetCoke powder as the feedstock. A person skilled in the art would be able to determine therefore whether graphitization of a carbon sample is partial, substantial, or full.

[0042] In Step 4, the process flow has an option to continue the process of Joule heating (continuous loop to Step 2) to enable substantially all fractions of the powder to be exposed to Joule heating and to be converted to the desired level of graphitization. The process also has an option to stop when all carbon powder grains have been exposed to the Joule heating process and until substantially all carbon has reached the desired level of graphitization. One example of graphitization is the full graphitization of the carbon into graphite. The process termination can be controlled by time of Joule heating and mixing or by applied energy dose (in units of kJ or MJ or kJ / g or MJ / kg) or by physical observation (either manually or automated) or material characterization of a sample portion that all carbon has been converted the desired level of graphitization.

[0043] The powdered material comprising carbon referenced in this invention may include at least one of the group comprised of, but is not limited to: calcinated petroleum coke, metallurgical coke, carbon black, activated carbon, char, carbon nanofibers, carbon fiber, graphitized carbon fiber, anthracite coal, green petroleum coke, asphaltenes, recycled-tire carbon black, bio char, wood char, plant char, pyrolyzed cellulose, conductive polymer, conductive plastic, plastic char, plastic ash and their combination thereof. The carbon of this invention may also include battery anode materials, such as natural or synthetic graphite, and spherical natural and synthetic graphite. It also includes recovered waste anode material. The carbon in the powdered material of this invention may also come from non-conductive materials that contain hydrogen, oxygen and / or nitrogen, such as: high density polyethylene, low density polyethylene, polypropylene, polystyrene, Styrofoam, polyethylene terephthalate (PET), polyacrylonitrile (PAN), cellulose, sugar, paraffins, urea, and any combination thereof. The non- conductive material of this invention may also include battery cathode materials.

[0044] The powdered material referenced in this invention includes all possible morphologies including: powder, grain, pellets, chunks, sphere-like, hollow sphere-like, particles, spheres, nanospheres, microspheres, rods, nanotubes, nanowires, and microwires, microfibers, matrix-forming structures, and their combinations. The powdered material referenced in this invention includes all material structures: non-porous, porous, nanoporous, microporous, and having layered structures. The powdered material referenced in this invention includes allpowder sizes, from sub-lOOnm to few millimeters. In one exemplary embodiment, the powdered material is Met Coke with grain sizes from 0.5 to 3 mm and surface area of 1-3 m2 / g, in another exemplary embodiment the powdered material is Carbon Black with prime particle size of 60 nm and structure size of about 1 pm, and surface area of 20-40 m2 / g.

[0045] The powdered material referenced in this invention may comprise metal-based catalysts that can facilitate the synthesis of standalone (as opposed to attached) secondary carbon formations, or secondary carbon formation and morphologies superimposed (attached) to the primary carbon (amorphous carbon, graphitized carbon, crystallized silicon material, crystallized silicon carbide, or any combination thereof) formation. For example, a graphite particle (primary formation) may have superimposed secondary formations, such as graphene, nanotubes, nanofibers, polyhedral graphene, carbon nano-onions structures, and any combination thereof. The secondary carbon formations, like carbon nanotubes, graphene, silicon or silicon carbide nanotubes, that have been formed with the help of Joule heating and mixing wherein the feedstock comprises a metal-based catalyst, may be free standing or attached to the amorphous carbon, the graphitized carbon, the crystallized silicon material, the carbon coated silicon material, or the crystallized silicon carbide. Catalysts include but are not limited to: Fe, Co, Ni, Cu, and other transition metals, iron acetate, iron chloride, iron acetylacetonate, iron oxide, cobalt oxide, other transition metal oxide, iron hydroxide, nickel hydroxide, other transition metal hydroxide, or their combination thereof. Common ingredients such as table salt (NaCI), baking soda (NaHCO3), washing soda (Na2CO3), and lye (NaOH) can also be used as catalysts for carbon nanotube growth.

[0046] The powdered material referenced in this invention may also comprise silicon- based additives such as silicon, silicon dioxide, silicon oxide (SiOx), or any combination thereof. The silicon-based additives may be in the form of random shape, nanospheres, microspheres, nanotubes, nanowires as well as any combination thereof. The silicon-based additives can facilitate the synthesis of secondary silicon-based nanostructures (for example, Si nanoparticles and nanowires, or SiC nanoparticles and nanowires) and morphologies that are free standing (not attached) or superimposed (attached) to the primary amorphous carbon, graphitized carbon, thecrystallized silicon material, the carbon coated silicon material, or the crystallized silicon carbide formation.

[0047] The powdered material referenced in this invention may also be infused with gaseous hydrocarbons that include but are not limited to methane (CH4), acetylene (C2H2), ethylene (C2H4), ethane (C2H6), and propane (CsHs). Hydrocarbons can facilitate the synthesis of secondary carbon-based nanostructures such as, graphene, nanotubes, nanofibers, polyhedral graphene, nano-onions, and morphologies that are superimposed to the primary carbon formation.

[0048] Figure 3 illustrates the process flow diagram of one embodiment of the present invention that enables flash Joule graphitization of carbon to graphite from carbon-based powder that removes any unwanted small-sized carbon particles (also known as carbon fines) during the process by in-situ oxidation of the unwanted fines as the Joule heating is applied. For one exemplary embodiment, in some cases, small-sized carbon fines are unwanted and need to be removed. Providing oxygen or air to the hot powder will burn and eliminate the smaller sized fraction of the carbon first before affecting the large-sized particles. The air or oxygen dose needs to be controlled so that it does not consume the larger size carbon particles that are desired. The air or oxygen dose needs to be controlled so that it does not create explosive conditions. The result is graphite synthesis via Joule heating with fraction of unwanted carbon fines eliminated. Different embodiments of this process may include more or fewer of these steps, and embodiments may comprise different steps.

[0049] In Step 1, a reactor is filled with powdered material comprising carbon wherein material is electrically conductive. In Step 2, a controlled amount of oxygen or air is applied to the powder in the reactor while electrical power is applied to the powder. In Step 3, the resulting Joule heating graphitizes the powder material into graphite while oxygen burns any small-sized carbon fines.

[0050] Figure 4 illustrates the process flow diagram of one embodiment of this innovation that enables flash Joule graphitization of carbon-based powder that removes any unwanted small-sized carbon impurities during the process by sieving the unwanted material as the Jouleheating is applied. Sieving in this innovation means any method of particle size classification that can be integrated with the Joule heating reactor. For one exemplary embodiment, in some cases, small-sized carbon fines are unwanted and need to be removed. Adding sieving capability to the reactor will filter and remove the smaller sized fraction of the carbon and preserve the largesized particles. The result is the graphitization of the carbon into graphite via Joule heating with fraction of unwanted carbon fines eliminated. Different embodiments of this process may include more or fewer of these steps, and embodiments may comprise different steps.

[0051] In Step 1, a reactor is filled with powdered material comprising carbon wherein material is electrically conductive. In Step 2, a powder sieving or filtering mechanism is applied in the reactor while at the same time electrical power is applied to the powder. Optionally, the sieving of fines can be synchronized with the Joule heating to occur in series or in parallel or with overlapping intervals. One exemplary system for in-situ sieving is to apply mesh grind at the bottom of the reactor and apply mechanical vibrations to the powder to sieve the fines from the powder. In Step 3, the resulting Joule heating graphitizes the powder material into graphite while the sieving action removes / filters any fines, including carbon fines. In Step 4, the filtered fines can be burned off as they are captured to generate heat that can be utilized in the process or the utility of the graphite production.

[0052] Figure 5 illustrates the process flow diagram of one embodiment of this innovation wherein the Joule heating is integrated with feedstock mixing and wherein the feedstock material comprises of carbon and silicon material. The carbon may be in the form of powder, fiber, or spherical. One example of carbon powder is spherical graphite for battery anodes. Another example of carbon fiber is carbon fiber-reinforced plastic (CFRP) typically found in the construction of wind turbine blades and automotive composites. The silicon material may be in the form of powder, nanosphere, microsphere, or fiber. One example of silicon material fiber is glass fiber-reinforced plastic (GFRP) typically found in the construction of wind turbine blades and automotive composites. It is preferred that the feedstock comprising carbon and silicon material has electrical resistivity of less than 1000 Qxcm. In terms of this invention, the silicon material includes silicon and all silicon compounds, specifically including silicon dioxide (silica), silicon monoxide, silicon carbide (SiC). The result of heating the feedstock that comprises carbonand silicon material is that one or both materials are converted to a more crystalline form of the material. The carbon material increases its crystallization, also known as graphitization, wherein the graphitization may be partial, substantial, and full carbon graphitization. The temperature range where carbon graphitizes depends on the carbon source and the morphology. In one exemplary embodiment, one range of carbon graphitization is from 1400 C to 3000 C. The silicon material also increases its crystallization, wherein the silicon material crystallization may be partial, substantial, and full. For one exemplary embodiment, the range of silicon material crystallization is from 400 C to 1000 C, and more specifically, from 600 C to 700 C. In another exemplary embodiment, the range of silicon oxide crystallization is from 1000 C to 1600 C, and more specifically, from 1000 C to 1200 C. Another exemplary case of silicon material conversion is the carbothermal conversion of amorphous silica in the presence of carbon to crystalline silicon carbide. For one exemplary embodiment, the range of silicon dioxide (silica) conversion to crystalline SiC is from 1600 C to 2700 C. Different embodiments of this process may include more or fewer of these steps, and embodiments may comprise different steps.

[0053] Composites of silicon / silica with graphite are desirable material for the production of advanced anodes for Li-ion batteries. Therefore, it is desirable to have feedstock that comprises both carbon and silicon or silica. One option for such feedstock is a naturally silicon- rich biochar from waste rice plants, wheat plants, sunflower, tobacco, or sugar cane. Another preferred material is sugarcane bagasse, a substantial biomass waste generated in the sugar industry after cane juice extraction. A bagasse bio char can be produced by pyrolysis of sugar cane waste and is commercially available material. Another preferred material are rice husks, a substantial biomass waste generated in the rice industry. A rice husk bio char can be produced by pyrolysis of the rice husk waste and is commercially available material. Graphite-silicon or graphite-silica composites that can be made with the processes of some embodiments of the invention have the advantage that the silicon or the silica in the graphite will be uniformly dispersed or distributed within the graphite compared to adding silicon / silica nanoparticles to a carbon powder as a feedstock. A composite of SiC is another possible product of the Joule heating process of this embodiment. When the silicon-based powder comprises silica in the presence of carbon, the silica powder may undergo carbothermal, and / or conversion fromamorphous SiOz to crystallized SiC and crystallized carbon, wherein the SiC and carbon crystallization may be partial, substantial, or full.

[0054] In Step 1, a reactor is filled with powder feedstock comprising carbon and silicon material wherein the feedstock material is electrically conductive. In Step 2, electrical power is applied to the feedstock material while mixing the powdered material, wherein the application of electrical power to the feedstock powder results in Joule heating the powder. In Step 3, the feedstock heating crystallizes the carbon from the powdered material into carbon with increased crystallinity, and / or crystalizes the silicon material powder into silicon material with increased crystallinity. The carbon or the silicon material or both can be either partially, substantially, or fully crystallized by the resulting Joule heating. For a given process set temperature, the carbon and the silicon material may have different levels of crystallization. In Step 4, the process flow has an option to continue the process of Joule heating to enable all fractions of the feedstock to be exposed to Joule heating and are crystallized. The process can be stopped when all feedstock has been exposed to the Joule heating process and the desired level of crystallization of either the carbon or the silicon material or both is achieved. The process stop can be controlled by verifying the material crystallization with online Raman or XRD tools, or by setting a recipe that delivers predetermined energy levels that are configured to achieve predetermined material crystallization. Additionally, the termination of the process can be controlled by time durations of Joule heating.

[0055] Figure 6 illustrates the process flow diagram of one embodiment of this innovation wherein the Joule heating is integrated with feedstock mixing and wherein the feedstock material comprises of carbon and plastic powders. The feedstock of this invention may be subjected (adjusted or controlled) to more than one Joule heating temperature, wherein low temperature range (< 1000 C) aids the conversion of the plastics and high temperature range (>1000 C) aids the conversion of the carbon. The carbon powder of this process includes amorphous carbon, like biochar, plastics char, carbon black, calcinated petroleum coke, carbon fiber, among others. The plastics of this innovation include raw and waste plastic materials such as PP, PE, HDPE, LDPE, PET, PS, PVC, PC, ABS and mixed waste but not limited to these examples. The plastic powder may also include polymers. The plastic may be in the form of a powder, film, or fiber. Oneexample of fiber is a Polypropylene fiber typically used in construction. One example of film is Polypropylene film orfoil used for packaging. Different embodiments of this process may include more or fewer of these steps, and embodiments may comprise different steps.

[0056] The result of heating the feedstock that comprises carbon and plastics is that both materials are converted to a degree that depends on the feedstock temperature. The temperature of the feedstock can be controlled by regulating the electrical powder of the Joule heating. In one exemplary embodiment, applying low electrical power per unit mass of feedstock, for example 10 to 50 kW / kg, would result in feedstock temperatures below 1000 C, and applying high electrical power per unit mass of feedstock, for example 50 to 200 kW / kg, would result in feedstock temperatures from 1000 C to 3000 C.

[0057] At high-power high-temperature Joule heating, the carbon powder increases its crystallization (graphitization), wherein the graphitization may be partial, substantial, and full carbon graphitization. The temperature range where carbon graphitizes depends on the carbon source and the morphology. For one exemplary embodiment, one range of carbon graphitization is from 1400 C to 3000 C.

[0058] At low-power low-temperature Joule heating, the plastic powder undergoes carbonization that converts the plastic to an amorphous carbon material (plastic char). For one exemplary embodiment, one range of plastics carbonization is from 400 C to 1000 C. During plastic carbonization, the plastic decomposes into carbon, waxes, oils, and gases. Possible gases include hydrogen, carbon monoxide, syngas, or methane. The wax, oil, and gas byproducts have high value and can be collected and used in other processes.

[0059] In Step 1 of the process disclosed in Figure 6, a reactor is filled with a feedstock blend of carbon powder and plastic powder wherein the feedstock is electrically conductive.

[0060] In Step 2 of the process, low temperature joule heating is applied to the feedstock while mixing the feedstock to convert at least some of the plastic into amorphous carbon. At temperatures less than 1000 C, the carbon powder from the feedstock will not graphitize or the graphitization will be minimal. Operating the Joule heating process under an inert atmosphere will aid the yield of converting plastics to amorphous carbon. When oxygen is present, some ofthe carbon from the plastic may burn out and decrease the conversion yield. Some of the amorphous carbon will create amorphous carbon seeds and some amorphous carbon will coat the carbon powder grains (or fibers, if the carbon is, in one exemplary embodiment, in the form of a carbon fiber). The morphology preference will depend on the initial feedstock preparation. When the plastic powder is smaller than the carbon grains the preferred conversion is to coat the carbon (grain or fiber). Melting the plastics over the carbon will also result in carbon coating. Increasing the ratio of plastic to carbon will also favor coating formation. When the plastic powder is comparable or larger size to the carbon powder the preferred conversion is to form amorphous carbon seeds.

[0061] The process of Step 2 can continue until all the plastic is carbonized. One process option is to loop to jump to Step 4 and add more plastic powder and return to process Step 2 to convert more plastics to amorphous carbon. The additional plastic powder in Step 4 can be added to the processed feedstock (now converted to carbon powder and amorphous carbon) while the Joule heating and mixing is ongoing. Alternatively, the Joule heating may stop, and the mixing may continue, while adding new plastics powder. Alternatively, the Joule heating may be ongoing and the mixing may be stopped while adding new plastics powder. This process loop can continue until there is no longer free volume in the reactor. Alternatively, the process can be continuous if the processed feedstock (after Step 2) is continuously being removed and new feedstock is added.

[0062] An optional Step 2A may be implemented to collect the byproduct waxes, oils, and gases. Alternatively, only the gases may be collected and the wax and oil left as part of the feedstock as additional carbon source for carbonization in Step 3.

[0063] In Step 3 of the process, high temperature Joule heating is applied to the feedstock while mixing the feedstock, to graphitize the amorphous carbon from the plastics and the carbon powder, wherein the carbon graphitization may be partial, substantial, or full carbon graphitization. At temperatures from 1400 C to 2200 C, partial graphitization will typically occur. At temperatures from 2300 C to 2600 C substantial graphitization will typically occur. At temperatures from 2700 C to 3000 C full graphitization will typically occur. The amorphous seed of Step 2 will be converted to a graphitized carbon seed during the Step 3 process, and theamorphous carbon that coats the carbon powder grains will be converted into graphitized coating. Both the bare and coated carbon powder will be converted into graphitized carbon. At high enough temperatures and heating times, the ultimate product will be graphite powder, from the amorphous carbon seeds and from the carbon powder. The result of the amorphous carbon coated carbon powder would be layered graphite powder. The resulting graphite is suitable for example as Li-ion battery anode material. An optional Step 3A may be implemented to collect the byproduct waxes, oils, and gases from any unreacted plastic powder or leftover waxes and oils from Step 2.

[0064] The process of Step 3 can continue until all the carbon has been graphitized to the desired level of graphitization. One process option is to continue to Step 4 and add more plastic powder and return to process Step 2 to convert more plastics to amorphous carbon. Repeated additions of amorphous carbon coating layers will result in layered graphitized carbon structure. In some exemplary embodiments, the structure is a layered graphite structure. With the ability to continuously add another layer to the graphite, its size and morphology can be controlled. In applications like graphite for Li-ion battery anodes, the porosity of the graphite grain is important to remain high as to allow Li ions intercalation.

[0065] The additional plastic powder in Step 4 can be added to the processed feedstock (now converted to graphitized carbon) while the Joule heating and mixing is ongoing. One limitation to the amount of new (non-electrica lly conductive) plastic powder that can be added is the requirement to keep the feedstock electrically conductive. This process loop can continue until there is no longer free volume in the reactor, or if the graphitized carbon is continuously removed, the process can be continuous.

[0066] One advantage of embodiments of the present invention with the looping option is that the new plastic are added to already hot graphitized powder which improves the efficiency of the process by not requiring new energy to reheat the feedstock volume. The temperature of the processed feedstock after Step 3 needs to be lower than the peak feedstock temperature of Step 2. This can be achieved by resting the powder or by actively cooling the powder. In case of active cooling, the removed heat can be utilized as process heat elsewhere.

[0067] One application of the looped process Steps 1-2, in which the plastic is converted into amorphous carbon coating, is to produce an amorphous carbon layer for a battery grade natural or synthetic graphite, for battery grade anode material. Addition of controllable amorphous carbon layer, 10 to 50 nm thick, over a 10 to 20 pm sized spherical graphite particle, helps with the formation of a SEI layer that forms as the graphite is being intercalated and allows reversable insertion and extraction of Li ions. Another application is to add a layer of amorphous carbon over Li-ion cathode material to help with the formation of a stable Cathode Electrolyte Interphase (CEI) layer. A prior-art description of forming an amorphous carbon layer over a lithium-iron-phosphate cathode from PVDF plastic and Joule heating is disclosed by Chen et al. (Small Methods 2025, 9, 2400680, DOI: 10.1002 / smtd.202400680). This prior art does not disclose feedstock mixing during the Joule heating. The innovation of this invention enables the controllable and uniform formation of amorphous carbon coating on cathode material (for example lithium cobalt oxide, lithium manganese oxide, lithium iron phosphate, and lithium nickel manganese cobalt oxide), and from variety of plastics.

[0068] In one embodiment of the present invention, a simple and efficient hydrogen production method is disclosed. In prior art hydrogen synthesis from plastic feedstock, presented by l / l / yss et al. (Adv. Mater. 2023, 2306763, DOI: 10.1002 / adma.202306763), 85% plastic waste and 15% carbon biochar feedstock were Joule heated to discompose the plastics into hydrogen and graphene, a process which required between 10 to 20 kJ / g of conversion energy and feedstock temperatures of 2700 C. In this process, after all the plastic was converted, the process had to stop, making it very inefficient. The innovation of this patent solves the problems of the prior art of hydrogen synthesis from plastic feedstock.

[0069] In one embodiment of the present invention, a process comprising of Steps 1-2 in a single batch offers a very efficient way of producing hydrogen from plastics. In the process of Steps 1-2, the plastic from the feedstock is converted into amorphous carbon and hydrogen but at only 3 kJ / g of conversion energy because the feedstock temperature was kept under 1000 C. A single batch low temperature Joule heating is already about 7X more efficient than the prior art process.

[0070] In another embodiment of the invention, a process comprising of continuously looped process Steps 2 and 4, offers an even more efficient way of producing hydrogen from plastics. After all the plastic in the feedstock has been converted into amorphous carbon in the process Step 2, additional plastic powder (without adding additional carbon powder) can be added to the already heated volume of feedstock in Step 4 (while the Joule heating and mixing is ongoing), providing continuous source of plastics to produce more amorphous carbon and hydrogen gas. As long as some of the plastic char (amorphous carbon) is removed from the reactor, the process can continue continuously, providing a very efficient method for hydrogen production. The amorphous carbon of this process may be used separately to graphitize it to graphite, which is more efficient than if the plastic was present in the feedstock.

[0071] Figure ? illustrates the process flow diagram of one embodiment of this innovation wherein the Joule heating is integrated with feedstock mixing and wherein the feedstock material comprises of carbon, silicon material, and plastic powders. The carbon may be in the form of powder, fiber, or spherical. In one exemplary embodiment, carbon powder is a spherical graphite for battery anodes. In another exemplary embodiment, carbon fiber is carbon fiber-reinforced plastic (CFRP) typically found in the construction of wind turbine blades and automotive composites. The silicon material may be in the form of powder, nanosphere, microsphere, or fiber. The plastic may be in the form of a powder, film, or fiber. The feedstock of this invention may be subjected (adjusted or controlled) to more than one Joule heating temperature, wherein a low temperature range (400 - 1000 C) aids the plastic carbonization and the silicon material crystallization, and high temperature range (1400 - 3000 C) aids the conversion of the carbon. The feedstock plastics of this innovation include raw and waste plastic materials. The plastic powder may also include polymers. The silicon-based feedstock of this innovation includes silicon, silica, silicon monoxide, silicon carbide or other silicon alloys. Different embodiments of this process may include more orfewer of these steps, and embodiments may comprise different steps.

[0072] The result of heating the feedstock that comprises carbon, silicon material, and plastics is that all materials are converted to a degree that depends on the feedstock temperature. The temperature of the feedstock can be controlled by regulating the electricalpowder of the Joule heating. At low-power low-temperature Joule heating, the plastic powder undergoes carbonization that converts the plastic to an amorphous carbon material (plastic char) and crystallizes the silicon material, wherein the silicon material crystallization may be partial, substantial, or full. At high-power high-temperature Joule heating, the carbon powder is crystallized / graphitized, wherein the crystallization / graphitization may be partial, substantial, or full. When the silicon-based powder is silica in presence of carbon (powder grains or amorphous carbon), the silica powder may undergo carbothermal and crystallization conversion from SiO2 to crystallized SiC and crystallized carbon and wherein the SiC and carbon crystallization may be partial, substantial, and full. The same SiC conversion may happen when the starting material is silicon. During plastics carbonization, the plastic decomposes into carbon, waxes, oils, and gases. Possible gases include hydrogen, carbon monoxide, syngas or methane. The wax, oil, and gas byproducts have high value and can be collected and used in other processes.

[0073] In Step 1 of the process disclosed in Figure 7, a reactor is filled with a feedstock blend comprising plastic powder, carbon powder, and silicon-based powder, wherein the feedstock blend is electrically conductive. The carbon powder can also be graphite or plastic char from previous processes.

[0074] In Step 2 of the process, low temperature joule heating is applied to the feedstock while mixing the feedstock to carbonize at least some of the plastic into amorphous carbon and / or crystallize some of the silicon material. Some of the amorphous carbon from the plastic carbonization may create amorphous carbon seeds and some amorphous carbon may coat either the carbon powder grains or the silicon-based grains or both. The description of the process in the context of grains is solely an example. The same description applies to all disclosed forms of the carbon and silicon.

[0075] One advantage of some embodiments of the present invention with the low temperature Joule heating step is to keep the silicon converting to silicon carbide or silicon oxide, while preventing the silicon oxide from converting into silicon carbide. Keeping the process temperatures below 1000 C will prevent silicon conversion to silicon carbide. Therefore, one product of the low temperature Joule heating with plastic and silicon / silica is the synthesis of a silicon or silica powder grain coated with a layer of amorphous carbon. Amorphous carboncoated silicon is desirable as anode for Li-ion batteries since it has higher specific energy capacity than other silicon-based species.

[0076] The process of Step 2 can continue until all the plastic is carbonized. One process option is to loop to jump to Step 4 and add more plastic powder and return to process Step 2 to convert more plastic to amorphous carbon. Repeated additions of amorphous carbon coating layers to an existing carbon coated silicon particle may result in a layered carbon-silicon structure. An optional Step 2A may be implemented to collect the byproduct waxes, oils, and gases. Alternatively, only the gases may be collected, and the wax and / or oil left as part of the feedstock as additional carbon source for carbonization in Step 3.

[0077] In Step 3 of the process, high temperature Joule heating is applied to the feedstock while mixing the feedstock to graphitize the amorphous carbon from the plastics and the carbon powder, wherein the carbon graphitization may be partial, substantial, or full carbon graphitization. The amorphous carbon that coats the carbon powder grains will be converted into graphitized layer. The amorphous carbon that coats the silicon-based powder grains will also be converted into a graphitized layer. One of the resulting products will be at least one of silicon material with graphitized carbon layer, silica with graphitized carbon layer, or silicon carbide with graphitized carbon layer, depending on the silicon-based powder size, and the Joule heating temperatures and duration (as measured by energy dose in kilo Joules per kilogram). In one exemplary embodiment, the silicon powder is 20 pm in size, the Joule heating temperature is 1600 C and the dose is 2 kJ / kg, and 5 seconds of process time, which will result in a partially converting the top layer of the silicon into silicon carbide and the amorphous carbon coating into partially graphitized carbon, but the core of the silicon particle will typically remain intact. One advantage of some embodiments of the present invention of the structure compromising a Si core— a partially crystallized SiC layer— partially graphitized carbon layer, is an excellent Li-ion battery anode material, because (i) the Si core has large specific capacity (mAh / g) and (ii) the partially graphitized carbon layer enables the formation of a stable SEI layer that allows stable reversable insertion and extraction of Li ions. At high enough temperatures and heating times, the amorphous carbon will be fully graphitized and will convert into a graphite layer.

[0078] An optional Step 3A may be implemented to collect the byproduct waxes, oils, and gases from any unreacted plastic powder or leftover waxes and oils from Step 2.

[0079] The process of Step 3 can continue until the desired level of crystallization and / or graphitization is achieved. One process option is to continue to Step 4 and add more plastic powder and return to process Step 2 to convert more plastic to amorphous carbon. Repeated addition of amorphous carbon coating layers will result in layered graphitized carbon enveloping either carbon powder or silicon-based particle. In some exemplary embodiments, the structure is layered graphite structure.

[0080] An additional plastic powder in Step 4 can be added to the converted feedstock (resulting from Step 3) while the Joule heating and / or mixing is ongoing. One limitation to the amount of new ( non-e lect rica lly conductive) plastic powder that can be added is the requirement to keep the feedstock electrically conductive. This process loop can continue until there is no longer free volume in the reactor unless the resulting converted feedstock from Step 3 is continuously removed, enabling the process can be continuous.

[0081] While the above description provides examples of one or more apparatus, methods, or systems, it will be appreciated that other apparatuses, methods, or systems are within the scope of the claims as interpreted by one of skill in the art.

Claims

AMENDED CLAIMS receivedbytheInternationalBureauon30June2025(30.06.2025)1.A method comprising: a.Joule heating a powder feedstock material in a reactor, b.mixing the powder feedstock material while Joule heating, c.wherein the powder feedstock comprises grains, and d.wherein the mixing comprises moving the powder feedstock grains with respect to each other.2.The method of claim 1, wherein mixing the powder comprises moving the powder feedstock grains relative to their absolute position within the reactor in multiple directions .3.The method of claim 2, wherein the mixing can be continuous or intermittent.4.The method of claim 3 wherein: a.the powder feedstock material comprises carbon.5.The method of claim 4 wherein: a.at least some of the powder feedstock material is graphitized.6.The method of claim 4 wherein: a.The feedstock further comprises a metal-based catalyst to facilitate the synthesis of secondary carbon formations and morphologies.7.The method of claim 6 wherein: a.the secondary carbon formations comprise graphene, nanotubes, nanofibers, polyhedral graphene, carbon nano-onions structures or any combination thereof.8.The method of claim 6 wherein: a.The metal-based catalyst comprises Fe, Co, Ni, Cu, or any combination thereof.9.The method of claim 4 wherein: a.carbon fines are removed by in-situ oxidation as theJoule heating is applied.

10. The method of claim 4 wherein: a.carbon fines are removed by sieving as the Joule heating is applied.

11. The method of claim 3 wherein: a.the powder feedstock material comprises carbon and a silicon material.

12. The method of claim 11 wherein: a.at least some of the carbon is crystallized, or b.at least some of the silicon material is crystallized13. The method of claim 11 wherein: a.at least some of the silicon material is converted into silicon carbide, and b.wherein at least some of the silicon carbide is crystalized.

14. The method of claim 11 wherein: a.the feedstock comprises a biochar comprising carbon and silica.

15. The method of claim 3 wherein: a.the powder feedstock material comprises carbon and plastic.

16. The method of claim 15 wherein: a.Joule heating is applied at two or more temperature levels .

17. The method of claim 16 wherein: a.Joule heating is applied at low temperature, below1000 C.

18. The method of claim 16 wherein: a.Joule heating is high power, high temperature, above1000 C.

19. The method of claim 17 wherein: a.at least some of the plastic is carbonized into amorphous carbon.

20. The method of claim 19 wherein: a.after Joule heating is applied at low temperatureJoule heating, Joule heating is applied at high temperature to increase the graphitization of either the amorphous carbon or the carbon or both.

21. The method of claim 15 wherein: a.at least some of the powder feedstock material is graphitized.

22. The method of claim 19 wherein: a.at least some of the carbon powder feedstock material is coated by a layer of the amorphous carbon from the plastic.

23. The method of claim 22 wherein: a.after Joule heating is applied at low temperatureJoule heating, Joule heating is applied at high temperature to increase the graphitization of either the amorphous carbon coating or the carbon or both.

24. The method of claim 22 wherein: a.the carbon powder feedstock material comprises graphite.

25. The method of claim 19 wherein: a.at least some of the amorphous carbon will create amorphous carbon seeds.

26. The method of claim 15 wherein: a.the carbon powder feedstock material comprises graphite, b.Joule heating is applied at low temperature below 1000C to carbonize the plastic into amorphous carbon, and c.the amorphous carbon is coating the graphite.

27. The method of claim 19 wherein:a.additional feedstock plastic is mixed into the feedstock material during the Joule heating.

28. The method of claim 19 wherein: a.at least some of the amorphous carbon or the carbon powder are removed from the reactor b.additional feedstock plastic is mixed into the feedstock material during the Joule heating, and c.the process is continuous.

29. The method of claim 15 wherein: a.at least one of byproduct wax, oil, or gas is collected.

30. The method of claim 15 wherein: a.the plastic is carbonized into amorphous carbon, b.the amorphous carbon is coating the carbon powder, c.additional plastic is mixed into the feedstock during the Joule heating, d.the additional plastic is carbonized into additional amorphous carbon, e.the additional amorphous carbon is coating the coated carbon powder, such that the structure comprises of carbon powder core and at least two layers of amorphous carbon.

31. The method of claim 30 wherein: a.the graphitization of the at least two layers of amorphous carbon is further increased.

32. The method of claim 15 wherein:a.the plastic is carbonized into amorphous carbon seeds, b.additional plastic is mixed into the feedstock during the Joule heating, c.the additional plastic is carbonized into additional amorphous carbon, and d.the additional amorphous carbon is coating the carbon seeds.

33. The method of claim 3 wherein: a.the powder feedstock material comprises carbon, silicon material, and plastic.

34. The method of claim 33 wherein: a.Joule heating is applied at two or more temperature levels.

35. The method of claim 33 wherein: a.at least some of the plastic is carbonized into amorphous carbon.

36. The method of claim 35 wherein: a.at least one of the carbon powder or the silicon material has not increased its crystallinity.

37. The method of claim 33 wherein: a.Joule heating is applied at low temperature below 1000C to carbonize at least some of the plastic into amorphous carbon.

38. The method of claim 37 wherein:a.after Joule heating is applied at low temperature,Joule heating is applied at high temperature to increase the crystallinity of either the amorphous carbon, the silicon material, the carbon powder, or all of them.

39. The method of claim 33 wherein: a.crystallization of at least some of the powder feedstock material is increased.

40. The method of claim 37 wherein: a.at least some of the silicon material or the carbon powder is coated by a layer of the amorphous carbon from the plastic.

41. The method of claim 40 wherein: a.after Joule heating is applied at low temperatureJoule heating, Joule heating is applied at high temperature to increase the crystallinity of at least one of the amorphous carbon coating, the silicon material, or the carbon powder.

42. The method of claim 33 wherein: a.the silicon material is at least partially converted into silicon carbide during the Joule heating, and b.wherein the silicon carbide is at least partially crystalized.

43. The method of claim 35 wherein: a.additional feedstock plastic is mixed into the feedstock material during the Joule heating.

44. The method of claim 35 wherein: a.at least some of the amorphous carbon, silicon material, or carbon powder are removed from the reactor, b.additional feedstock plastic is mixed into the feedstock material during the Joule heating, and c.the process is continuous.

45. The method of claim 33 wherein: a.at least one of byproduct wax, oil, or gas is collected.

46. The method of claim 33 wherein: a.the plastic is carbonized into amorphous carbon, b.the amorphous carbon is coating at least the silicon material, c.additional plastic is mixed into the feedstock during the Joule heating, d.the additional plastic is carbonized into additional amorphous carbon, e.the additional amorphous carbon is coating the coated silicon material, wherein the structure comprises of silicon material core and at least two layers of amorphous carbon.

47. The method of claim 46 wherein: a.the crystallinity of the at least two layers of amorphous carbon is further increased.

48. A method comprising:a.Joule heating a powder feedstock material comprising electrically conductive plastic char in a reactor, b.mixing the powder feedstock material while Joule heating, c.adding plastic powder feedstock during the Joule heating and mixing, d.converting the plastic powder feedstock into plastic char and at least hydrogen gas, e.collecting the hydrogen gas, f.removing some of the plastic char from the reactor, g.adding more plastic powder feedstock such that the process is continuous.

49. A method comprising: a.Joule heating a powder feedstock material in a reactor, wherein b.the powder feedstock material comprises carbon and plastic, c.at least some of the plastic is carbonized into amorphous carbon, and d.at least some of the powder feedstock material is coated by a layer of the amorphous carbon.

50. The method of claim 49, wherein: a.the powder feedstock material further comprises spherical graphite.

51. The method of claim 49, wherein: a.the powder feedstock material further comprises silicon material.

52. The method of claim 49, wherein: a. at least some of the powder feedstock material is covered with multiple layers of coating.

53. The method of claim 49, wherein: a. the amorphous carbon coating layer is further crystalized.

54. The method of claim 49, wherein: the feedstock and the amorphous carbon are further crystalized

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