Composition for converting biochar to low surface area graphite

Abstract

The present disclosure relates to compositions for feedstocks suitable for graphitization. In particular, the present disclosure relates to compositions necessary to produce graphite products having desirable properties using difficult-to-graphitize carbon materials.

Description

[Technical Field]

[0001] The present invention relates to a composition suitable for converting biochar into low surface area graphite suitable for a wide range of applications, the composition comprising biochar, a metal compound, a liquid, and an additive blend selected from one or more of a surfactant, a binder, a dispersant, a rheology modifier, a wetting agent, an antifoaming agent, and any combination thereof. [Background technology]

[0002] Graphite can be synthesized or obtained from natural deposits. Some carbon materials, such as coke and mesophase pitch, can be converted to graphite simply by heating, and are therefore referred to as graphitizable. Rosalind Franklin (1999) described graphitizable carbon as being convertible to crystalline graphite by heating up to 3000°C. Other carbon materials, on the other hand, cannot be converted to graphite simply by heating and do not spontaneously graphitize at any temperature, and are therefore described as non-graphitizable carbon materials.

[0003] The physical properties of these two types of carbon are very similar before heat treatment. Both materials are generally derived from hydrocarbons and initially contain other elements, such as hydrogen, oxygen, nitrogen, and sulfur. Graphitic carbons tend to be aromatic in structure, while non-graphitic carbons tend to be aliphatic. Therefore, the key to distinguishing the two is the H:C ratio, which is lower for aromatics. Heating removes the heteroelements, leaving only a residual structure (carbon only). A key step toward the formation of high-quality, synthetically derived graphite is the polycondensation reaction that forms large polyaromatic hydrocarbons (PAHs). Upon heating, PAHs align to form the graphitic structure; however, in some non-graphitic carbons, this structural alignment can be terminated by cross-linking. However, in many others, PAHs simply do not form upon heat treatment, resulting in very small graphite crystallites even when heated to 3000 °C.

[0004] Demand for graphite has increased significantly due to its need for lithium-ion batteries. Mining natural graphite sources has a significant environmental impact. Meanwhile, the production of synthetic graphite requires crude oil and other non-renewable resources. To produce graphite sustainably and economically, new methods are needed that utilize renewable sources of carbon material for graphitization. One such source is renewable biomass, which, when heated, forms carbonaceous char, a non-graphitizable form of carbon. [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] Franklin, RE, “Crystallite growth in graphitizing and non-graphitizing carbons.” Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1951, 209(1097), pp. 196-218. Summary of the Invention [Problem to be solved by the invention]

[0006] The present disclosure provides a composition comprising biochar, a metal compound, a liquid in which the metal compound has minimal solubility, and an additive blend selected from one or more of surfactants, binders, dispersants, rheology modifiers, wetting agents, antifoaming agents, and any combination thereof. This granular wet slurry mixture possesses a unique set of properties that, when heat-treated, allows it to produce graphite materials with low surface areas at high conversion rates. By varying the amounts of the components, the properties of the graphite material can be tailored to suit specific applications. This is not easily achievable using dissolved metal compounds because the solubility of metal compounds is limited in a given liquid, and controlling the size of precipitated particles beyond a limited range is practically impractical. Methods for producing such compositions are also disclosed. [Means for solving the problem]

[0007] In a first aspect, a composition is provided comprising a mixture of biochar, a metal compound, a liquid, and an additive blend, the mixture comprising: (a) between about 1% and about 90% by weight of biochar; (b) between about 2% and about 90% by weight of the metal compound; (c) between 0.001% and about 83% by weight of the liquid; and (d) between about 0.001% and about 5% by weight of an additive blend, wherein the additive blend is selected from one or more of a surfactant, a binder, a dispersant, a rheology modifier, a wetting agent, an antifoaming agent, and any combination thereof.

[0008] It can be understood that any weight percentage of the four components can be selected from these stated ranges, provided that they add up to 100%. In one embodiment, the liquid and the metal compound are selected such that the metal compound has minimal solubility in the liquid when the composition is used, hi a further embodiment, the liquid is water.

[0009] In one embodiment, the metal compound comprises a transition metal, hi a further embodiment, the transition metal is selected from chromium, zirconium, molybdenum, ruthenium, rhodium, palladium, silver, cadmium, zinc, copper, nickel, cobalt, iron, manganese, chromium, vanadium, or any combination thereof.

[0010] In one embodiment, any non-metallic portion of the metal compound may instead result from the use of any inorganic acid to produce a salt such as a fluoride, chloride, sulfate, nitrate, phosphate, or carbonate. Alternatively, an organic acid can produce an organic salt. Upon heat treatment, most of these inorganic and organic compounds can decompose to form metal oxides, so they can also be used indirectly. Other intermediate compounds may also be formed depending on the starting metal compound selected.

[0011] In one embodiment, the metal compound is a transition metal oxide, hi a further embodiment, the transition metal oxide is selected from oxides of iron, copper, nickel, manganese, vanadium, tin, chromium, zinc, titanium, and cobalt, or any combination thereof.

[0012] In one embodiment, the mixture is dried to comprise, on a dry weight / weight basis, (a) between about 9.5% and about 90% metal compound by weight, (b) between about 0.001% and about 5% additive blend by weight, and (c) between about 5% and about 90.5% biochar by weight.

[0013] In one embodiment, the mixture is dried to comprise, on a dry weight / weight basis, (a) between about 19% and about 82% metal compound, (b) between about 0.001% and about 5% additive blend, and (c) between about 13% and about 81% biochar. Any weight percentage of these three components can be selected from these recited ranges, provided that the total adds up to 100%.

[0014] In one embodiment, the metal compound is a metal oxide. In one embodiment, the metal oxide is a transition metal oxide. In one embodiment, the transition metal oxide is selected from oxides of iron, copper, nickel, manganese, vanadium, tin, chromium, zinc, titanium, and cobalt, or any combination thereof.

[0015] In one embodiment, the metal oxide is iron oxide. In one embodiment, the mixture, upon drying, comprises, on a dry weight / weight basis, (a) between about 9.5% and about 80% iron oxide, (b) between about 0.001% and about 5% of the additive blend, and (c) between about 20% and about 90.5% biochar, the biochar having about 70% fixed carbon. Any weight percentage of these three components can be selected from these stated ranges, provided that the total adds up to 100%.

[0016] In one embodiment, the mixture, upon drying, comprises, on a dry weight / weight basis, (a) between about 19% and about 67% iron oxide, (b) between about 0.001% and about 5% of the additive blend, and (c) between about 33% and about 81% biochar, the biochar having a fixed carbon content of 70% or greater. Any weight percentage of these three components can be selected from these recited ranges, provided that they add up to 100%.

[0017] In one embodiment, the biochar is produced by thermally treating woody biomass. In one embodiment, the biochar in the mixture is in particulate form.

[0018] In one embodiment, the biochar has an initial particle size of less than about 50 mm. In one embodiment, the metal compound in the mixture is in particulate form. In one embodiment, the metal compound and the biochar are both in particulate form.

[0019] In one embodiment, the metal compound has an initial particle size of less than about 5 mm. In one embodiment, the biochar has an initial particle size of less than about 50 mm and the metal compound has an initial particle size of less than about 5 mm.

[0020] In one embodiment, the biochar has a particle size of less than about 800 μm. In one embodiment, the particle size of the biochar is less than about 500 μm. In one embodiment, the particle size of the metal compound is less than about 100 μm.

[0021] In one embodiment, the particle size of the metal compound is less than about 75 μm. In one embodiment, the additive formulation includes two or more of a surfactant, a binder, a dispersant, a rheology modifier, a wetting agent, an antifoaming agent, and any combination thereof. The additives should be selected based on the selected metal compound and the selected liquid to achieve appropriate properties for the mixture in the selected processing step. In one embodiment, the selected metal compound tends to agglomerate, in which case an appropriate liquid-solid surfactant is required; in other embodiments, the biochar or metal compound is not easily wettable by the liquid, in which case a wetting agent needs to be added to achieve a homogeneous slurry mixture. In certain embodiments, the slurry may need to be pumped from one vessel to another, in which case a rheology modifier may be required to achieve the appropriate viscosity; in other embodiments, the selected liquid may result in foam generation during the slurry mixing process, in which case an antifoaming agent may be required.

[0022] In one embodiment, the additive formulation is selected from the group consisting of acResin®, ACRODUR®, ACROFLOR®, ACRONAL®, AEROSOL C-61, AG 6202, ALCOSPERSE 175, ALMIPAL P, Amidex®, aminoethylethanolamine, ammonium fluoride, AMMONYX M, AQACell®, Aquatreat BW30, Arkopal, Armac®, Armeen®, Armid O, Attagel®, Aziridine, BASONAT® Polyisocyanate, Bronidox, BTBAB-90, BTBAC-50, Bteac-50, BTMAC-50, BTMAH-40, BUTOFAN® Styrene-Butadiene Binder, BUTONAL® Styrene-Butadiene Binder, Butyl Stearate, Calcium Stearate, Darvan®, Dispex®, Dodecandioic Acid, DYSPERSE®, EDAPLAN®, EFKA®, ENORDET, Ethoduomeen T / 25, EURAMAAT, EUR-AMID, EURANAAT, EURASOL, EUROGLYC, EUROQUAT, EUROWET, EUROXIDE, EXOdis PC30, FOAMASTER MO 2133, FOAMSTAR®, Heliogen Blue D 7079, HYDROPALAT®, JONCRYL®, Lauryl Alcohol, Repearl MSC, Repearl NTD, Magna Surf®, MERPOL SE, METOLAT®, NANSA, Oleamide, Oleic Acid, Pasatell M-182 (2-798), PEG-400, Pentaerythritol Oleate, Poise 520, Poise 530, Polyamide, Polyester, POLYFON H, Polyglycol, Polyman®, Polymerizable Additive, Potassium Soyate, Quickpearl PK3, REAX®, REWOCID DU185 SE, Rewopol SB L203, Rheovis®, ROKAmer 1010 / 50, Schercomid®, SDS, Sibet®, Sico 50BC, Sidos 70, Sodium Dodecylbenzenesulfonate, Sodium N-Hexadecanoyl-L-alanine, Sodium Silicate, Sorbitan Monooleate, Sorbitan Monopalmitate, Steamcare B12, Stearyl Chloride, STYROFAN®, SugaDet APG-10, Sulfoccinate LSS, Sulfochem®, Sulfated Butyl Oleate, Sunnol®, SURFACARE O ACID, TBAH-40, TBAHS-50, Tensol® DDM, TERGITOL®, TLMAC-30, TMAC-100 ARQUAD 41-100, Tomamine Amphoteric 12, triethanolamine, triethylbenzylammonium chloride, TWEEN 80, UFACID K, Vitec®, YB-0100, YB-150, YB-191, YB-2000, YB-904, YBASD-200, or any combination thereof.

[0023] In another aspect, a method is provided for heat treating a composition as determined above to a temperature above the reduction temperature of said metal compounds, thereby reducing said metal compounds to elemental metals or alloys and converting amorphous biochar carbon to crystalline graphitic carbon.

[0024] In one embodiment, the conversion of amorphous char to crystalline graphite formed by said heat treating said mixture is greater than about 50%. In one embodiment, the conversion to graphite is greater than about 75%.

[0025] In one embodiment, the crystalline graphite formed by said heat treating said mixture has a crystallinity of greater than about 90%. In one embodiment, the crystallinity of the crystalline graphite is greater than about 95%.

[0026] In one embodiment, the specific surface area of the graphite formed by the heat treatment of the composition as determined above is about 50 m 2 / g. In one embodiment, the specific surface area of the graphite is about 30 m 2 / g.

[0027] In one embodiment, the method further comprises: i) heat treating biomass in particulate form at a temperature between about 200°C and about 1000°C under inert conditions to form granular biochar; ii) grinding the biochar to obtain a particle size of less than about 800 μm, more preferably less than 500 μm; iii) milling a suitable metal compound to obtain a particle size of less than about 100 μm, more preferably less than 75 μm; iv) combining the resulting biochar with the metal compound, liquid, and additive blend; v) heating the mixture to between about 400°C and about 3000°C under inert conditions to produce graphitic carbon.

[0028] In one embodiment, the biomass is heat treated in water in a hydrothermal step to produce the biochar. In one embodiment, the biomass is heat treated under inert conditions in a dry pyrolysis step to produce the biochar.

[0029] In one embodiment, the biomass is a logging residue. In one embodiment, the forestry residue is sawdust. In one embodiment, the biomass is lignocellulosic biomass or a lignin derivative.

[0030] In one embodiment, the biomass is wood chips or any other wood-based material. In one embodiment, the liquid is water.

[0031] In one embodiment, the liquid and the metal compound are selected such that, in use, the metal compound has minimal solubility in the liquid. In one embodiment, in step iv), the metal compound is combined with the biochar by wet mixing together with the additive formulation in a mixer.

[0032] In one embodiment, in step iv), the metal compound is mixed with the biochar by wet grinding together with an additive blend in a mill. In one embodiment, in step iv), the water granular slurry is formed by mixing the metal compound with the additive blend in water using a mixer to form a granular metal compound slurry.

[0033] In one embodiment, the additive blend for the particulate metal compound slurry comprises a surfactant, a binder, a dispersant, a rheology modifier, a wetting agent, an antifoaming agent, or any combination thereof.

[0034] In one embodiment, in step iv), a granular aqueous slurry is formed by mixing the biochar with an additive blend in water using a mixer to form a granular biochar slurry.

[0035] In one embodiment, the additive formulation for the granular biochar slurry further comprises a surfactant, a binder, a dispersant, a rheology modifier, a wetting agent, a defoamer, or any combination thereof.

[0036] In one embodiment, the particulate metal compound slurry is combined with the particulate biochar slurry and then mixed together in a mixer. In one embodiment, the mixture obtained in step (iv) is heated in step (v) to between about 400°C and about 3000°C under inert conditions using a controlled atmosphere oven, furnace, or other heating device to produce graphitic carbon, the heat treatment temperature being above the reduction temperature of the selected metal compounds to reduce them to their elemental metal or alloy state.

[0037] In one embodiment, the metal compound is a metal oxide. In one embodiment, the metal oxide is a transition metal oxide. In one embodiment, the transition metal oxide is selected from oxides of iron, copper, nickel, manganese, vanadium, tin, chromium, zinc, titanium, and cobalt, or any combination thereof.

[0038] The foregoing and other aspects or advantages of the present invention may become apparent to one skilled in the art using the detailed description, images, analysis results, and performance test results provided herein. [Brief explanation of the drawings]

[0039] [Figure 1] FIG. 1 shows an image of the microwave applicator used to produce the graphite samples described herein. [Figure 2a] FIG. 10 shows an image of the placement of a sample crucible in a microwave applicator. [Figure 2b] FIG. 10 shows an image of the sample crucible at high temperature. [Figure 3] FIG. 1 is an XRD diffractogram of the graphite sample produced in Example 1. [Figure 4] FIG. 1 is an XRD diffractogram of the graphite sample produced in Example 2. [Figure 5] FIG. 1 is an XRD diffractogram of the graphite sample produced in Example 3. [Figure 6] Process diagram showing the overall conversion of biomass into graphite anode powder for lithium-ion batteries. DETAILED DESCRIPTION OF THE INVENTION

[0040] The following description sets forth numerous example configurations, parameters, etc. However, it is recognized that such description is not intended to limit the scope of the present invention, but is instead provided as a description of example embodiments.

[0041] All references, including patents and patent applications, cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art, nor does the discussion of any reference constitute an admission that such reference forms part of the common general knowledge in the art, in New Zealand or any other country.

[0042] definition In each instance herein, in the description, embodiments, examples, and claims, the terms "comprising," "including," and the like, should be read expansively, without limitation. Thus, unless the context clearly dictates otherwise, throughout this specification and the claims, the words "comprise," "comprising," and the like should be interpreted in an inclusive sense, as opposed to an exclusive sense, i.e., "including but not limited to."

[0043] As used herein, the articles "a" and "an" are used to refer to one or to more than one (i.e., one or more) of the grammatical object of the article. By way of example, "an element" can be interpreted to mean one element or more than one element.

[0044] The term "about" or "approximately" is used to indicate a broader range centered around a given value, and unless otherwise clear from the context, refers to a broader range centered around the least significant digit, such as "about 1.1" meaning a range of 1.0 to 1.2. When the least significant digit is unclear, the term "about" refers to a factor of 2, e.g., "about X" means a value in the range of 0.5 to 2 times, e.g., about 100 means a value in the range of 50 to 200. Furthermore, all ranges disclosed herein should be understood to encompass any and all subranges subsumed therein. For example, a range "less than 10" can encompass any and all subranges between (and including) a minimum of zero and a maximum of 10, i.e., any and all subranges having a minimum value of zero or greater and a maximum value of 10 or less, e.g., 1 to 4.

[0045] Unless otherwise defined, all technical and scientific terms and nomenclature used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. Notwithstanding that the numerical ranges and parameters setting forth broad ranges are approximations, the numerical values set forth in the specific non-limiting examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements at the time of writing. Moreover, unless otherwise clear from the context, numerical values presented herein have an implied precision given by the first significant digit. Thus, the value 1.105 means a value between 1.0 and 1.2, while 1.105 x 10 2 The value 110.5 given by means of the formula means a value between 100 and 120.

[0046] As used herein, the terms "biochar" or "carbonaceous char" or "char" are used interchangeably to mean the material resulting from the pyrolysis of carbonaceous material in an inert atmosphere.

[0047] As used herein, the terms "metal compound" or "metallic compound" are used interchangeably and refer to organic or inorganic materials that contain a transition metal or a non-transition metal (e.g., but not limited to, chromium, zirconium, molybdenum, ruthenium, rhodium, palladium, silver, cadmium, zinc, copper, nickel, cobalt, iron, manganese, vanadium, sodium, magnesium, potassium calcium, tin, or lead).

[0048] As used herein, the term "minimal solubility," when used in reference to a metal compound, means that less than about 0.1 g of the metal compound can be dissolved in about 100 ml of a selected liquid at a neutral pH of 7.

[0049] As used herein, the term "amorphous" means a material that does not possess long- or short-range structural order, in contrast to a crystal, which has atoms arranged in the form of a regular lattice made up of repeating defined unit cells.

[0050] As used herein, the term "allotrope" refers to a substance that has the same elemental composition (such as pure carbon) but a different morphology or atomic organization (e.g., diamond vs. graphite, or amorphous biochar / char vs. graphite).

[0051] As used herein, the term "thermally treated" means any heat treatment process applied to biomass at a temperature sufficient to produce biochar, including hydropyrolysis and dry pyrolysis.

[0052] As used herein, the term "liquid" means a fluid in a liquid phase, such as, but not limited to, water. As used herein, the term "water" means a water source and includes low quality water sources such as salt water, brackish water or wastewater.

[0053] As used herein, the term "additive formulation" refers to an agent selected from one or more of a surfactant, a binder, a dispersant, a rheology modifier, a wetting agent, an antifoaming agent, and any combination thereof. Alternatively, "additive formulation" may refer to a formulation containing one or more agents selected from one or more of a surfactant, a binder, a dispersant, a rheology modifier, a wetting agent, an antifoaming agent, and any combination thereof. It should be understood that an additive formulation may include any number of combinations of surfactants, binders, dispersants, rheology modifiers, wetting agents, and / or antifoaming agents. For example, as shown in Table 1, an additive formulation may include at least a binder and at least a surfactant. Alternatively, an additive formulation may include any combination of three or more, four or more, or five or more of a surfactant, a binder, a dispersant, a rheology modifier, a wetting agent, and / or an antifoaming agent. Furthermore, it should be understood that a single agent may have multifunctional effects. For example, a single agent may function as both a surfactant and a wetting agent. The additive formulation may optionally include one or more additional agents (including, but not limited to, for example, one or more carriers, one or more solvents, or combinations thereof).

[0054] Table 1. Example additive formulations including possible combinations of at least drug a and at least drug b.

[0055] [Table 1]

[0056] Composite of biochar, metal compounds, liquid, and additive formulation The compositions described herein include a mixture of biochar, insoluble metal compounds, a liquid, and an additive formulation. The biochar is typically derived from the pyrolysis of woody biomass. The metal compounds typically include transition metals. The liquid is typically water. The additive formulation includes a single or multi-functional mixture of one or more components selected from surfactants, binders, rheology modifiers, dispersants, wetting agents, antifoaming agents, or any combination thereof. To produce the desired mixture, the components are mixed or ground together or separately and then blended. To convert the mixture to graphite, the mixture may then be subjected to a heat treatment procedure at temperatures between 400°C and 3000°C for a soaking time between 60 seconds and 20 hours, depending on the reduction temperature of the selected metal compound.

[0057] Generally, biochar is produced by heat-treating or "pyrolyzing" biomass starting material (e.g., wood chips, sawdust, forest waste, or any plant-derived raw material) under an inert atmosphere (e.g., nitrogen) at temperatures between 200°C and 1000°C for between a few seconds ("fast" pyrolysis) and several hours. Alternatively, biomass can be converted to char using hydrothermal processing. Here, char and water are placed in an autoclave at about 360°C and a pressure of about 20.0 MPa for the same period as pyrolysis, followed by drying. In all cases, the resulting char consists primarily of elemental carbon, with the so-called fixed carbon content being at least 40% or greater, but more commonly 60% or greater. The remainder is composed of a set of heteroatoms (primarily hydrogen, oxygen, nitrogen, and sulfur). In addition, the char may contain volatile substances described as aliphatic or aromatic hydrocarbons, which are of sufficiently high molecular weight not to evaporate during the heat treatment. The exact composition may depend on the heat treatment conditions and the biomass starting material selected. The resulting char material is typically referred to as "green" char. Any of the biochar materials previously described can be selected to produce the compositions described herein.

[0058] The liquid-insoluble metal compound may be any one of a myriad of possible metal compounds. The metal component of the compound is preferably a transition metal (such as, but not limited to, chromium, zirconium, molybdenum, ruthenium, rhodium, palladium, silver, cadmium, zinc, copper, nickel, cobalt, iron, manganese, chromium, vanadium, or any combination thereof). However, the metal component may also be composed of a non-transition metal (i.e., sodium, magnesium, potassium, calcium, tin, lead, etc.). Alternatively, the non-metal portion of the compound may be derived from the use of any inorganic or organic acid to produce a salt, such as a fluoride, chloride, sulfate, nitrate, phosphate, carbonate, etc. Upon heat treatment, most organic and inorganic compounds decompose to form metal compounds, so they can also be used indirectly. Other intermediate compounds may also be formed depending on the starting metal compound selected.

[0059] To achieve uniform distribution during mixing and ensure that closed or inaccessible voids are minimized, both the biochar and the metal compounds must be milled, either separately or together. The milling process can be carried out using any conventional mill, such as a ball mill, rod mill, pebble mill, bead mill, jet mill, planetary mill, vibratory mill, disk mill, attritor mill, or air-classifying hammer mill. Co-milling of the char and metal compounds achieves intimate contact, but the achieved particle size distribution of each component is difficult to control. The biochar is milled to a particle size of less than about 800 μm, more preferably less than about 500 μm. The metal compounds are milled to a particle size of less than about 100 μm, more preferably less than about 75 μm.

[0060] In general, several options exist for mixing biochar with metal compounds. If the metal compound is water-soluble, it is possible to simply dissolve the compound in distilled or deionized water, immerse the biochar in this solution, and then dry it. Because the metal compound is uniformly dissolved in water, it will also be uniformly distributed throughout the biochar after drying. However, in this case, it is difficult to control the relative amounts of char and metal compound. The maximum amount of metal compound that can be deposited is directly limited by the maximum solubility of the compound in a given liquid, which can be largely constant over the usable temperature range (e.g., 0°C to 100°C for water). Furthermore, achieving uniform drying in practice is very difficult on non-uniform surfaces or porous particles, as is controlling the particle size distribution of the dried metal compound.

[0061] The two solids can be mixed simply by dry blending in a suitable solid mixer or by co-milling. While this approach allows for direct control of the relative amounts of each component, achieving uniform distribution is difficult when mixing the two solids. Biochar tends to be highly porous with irregular grooved surfaces, which makes it difficult to uniformly distribute metal compound particles across the exposed surfaces, both inside and out. Furthermore, metal compounds often tend to agglomerate, which can result in substantially larger particle sizes than initially achieved during milling.

[0062] A third option combines the traditional methods through the use of a wet granular slurry. In this case, both granular insoluble solids are placed in suspension using a suitable liquid medium, subsequently mixed, and then the medium is optionally removed to obtain a dry mixture. This approach allows the two components to be mixed in a fixed ratio. In this way, the relative amounts of each component and their distribution can be precisely adjusted to achieve the exact set of final properties required for a particular application.

[0063] Furthermore, the use of a liquid slurry means that the metal compounds are uniformly distributed across and over the surface of the biochar. Typically, the medium or liquid is water, with a mass ratio of liquid to other components between 0.3 and 5. To ensure sufficient wetting, uniform distribution of each particle, and retention of distribution upon drying, it is necessary to use an additive blend for one or both granular slurries. The additive blend comprises a multifunctional mixture of components including one or more of the following: surfactants, binders, dispersants, rheology modifiers, wetting agents, antifoaming agents, and any combination thereof.

[0064] Depending on the insoluble metal compound selected and the source of biochar, the selection and relative amounts of each component in the additive formulation may need to be varied to achieve optimal distribution while undergoing the required processing steps. For example, the selected metal compound may tend to agglomerate, in which case a suitable liquid-solid surfactant may be required; in other situations, the biochar or metal compound may not be readily wettable by the liquid, in which case a wetting agent may need to be added to achieve a homogeneous slurry mixture. Certain processes may require pumping the slurry from one vessel to another, in which case a rheology modifier may be required to achieve the appropriate viscosity; in other cases, the selected liquid may result in foam generation during the slurry mixing process, and therefore an antifoaming agent may be required.

[0065] The additive formulation components are acResin®, ACRODUR®, ACROFLOR®, ACRONAL®, AEROSOL C-61, AG 6202, ALCOSPERSE 175, ALMIPAL P, Amidex®, aminoethylethanolamine, ammonium fluoride, AMMONYX M, AQACell®, Aquatreat BW30, Arkopal, Armac®, Armeen®, Armid O, Attagel®, Aziridine, BASONAT® Polyisocyanate, Bronidox, BTBAB-90, BTBAC-50, Bteac-50, BTMAC-50, BTMAH-40, BUTOFAN® Styrene-Butadiene Binder, BUTONAL® Styrene-Butadiene Binder, Butyl Stearate, Calcium Stearate, Darvan®, Dispex®, Dodecandioic Acid, DYSPERSE®, EDAPLAN®, EFKA®, ENORDET, Ethoduomeen T / 25, EURAMAAT, EUR-AMID, EURANAAT, EURASOL, EUROGLYC, EUROQUAT, EUROWET, EUROXIDE, EXOdis PC30, FOAMASTER MO 2133, FOAMSTAR®, Heliogen Blue D 7079, HYDROPALAT®, JONCRYL®, Lauryl Alcohol, Repearl MSC, Repearl NTD, Magna Surf®, MERPOL SE, METOLAT®, NANSA, Oleamide, Oleic Acid, Pasatell M-182 (2-798), PEG-400, Pentaerythritol Oleate, Poise 520, Poise 530, Polyamide, Polyester, POLYFON H, Polyglycol, Polyman®, Polymerizable Additive, Potassium Soyate, Quickpearl PK3, REAX®, REWOCID DU185 SE, Rewopol SB L 203, Rheovis®, ROKAmer1010 / 50, Schercomid®, SDS, Sibet®, Sico 50BC, Sidos 70, Sodium Dodecylbenzenesulfonate, Sodium N-Hexadecanoyl-L-alanine, Sodium Silicate, Sorbitan Monooleate, Sorbitan Monopalmitate, Steamcare B12, Stearyl Chloride, STYROFAN®, SugaDet APG-10, Sulfoccinate LSS, Sulfochem®, Sulfated Butyl Oleate, Sunnol®, SURFACARE O ACID, TBAH-40, TBAHS-50, Tensol® DDM, TERGITOL®, TLMAC-30, TMAC-100 ARQUAD 41-100, Tomamine Amphoteric 12, Triethanolamine, Triethylbenzylammonium Chloride, TWEEN 80, UFACID K, Vitec®, YB-0100, YB-150, YB-191, YB-2000, YB-904, YBASD-200, and combinations thereof.

[0066] Thus, after optional mixing and pre-drying, a blended composite consisting of biochar, metal compounds, and additive blends is obtained. When such a blend is subjected to heat treatment at temperatures between 400°C and 3000°C to produce graphite, several important changes occur. Residual liquid is removed, and substantially all of the residual heteroatoms and volatiles present in the biochar are removed, resulting in a material that is essentially carbon and has a fixed carbon content of greater than about 99%. This material is conventionally referred to as "calcined" or "fully carbonized" biochar. The amount of fully carbonized biochar is approximately equal to the fixed carbon content of the original biochar. In the presence of carbon, such as biochar, at elevated temperatures above 400°C, metal compounds or any intermediate compounds formed can be reduced to their metallic state. Reduction is typically accomplished under an inert atmosphere, and a portion of the biochar is consumed. Thus, during the heat treatment, the char is carbonized to pure carbon, and the metal compounds are reduced to pure metals or alloys.

[0067] Because additives are most commonly long-chain polymers, they can decompose when heated above several hundred degrees Celsius. This can be accompanied by significant mass loss as gaseous decomposition products are formed. In some cases, lighter elements or compounds present may also evaporate or sublime, depending on the final temperature. Furthermore, because the additive formulation typically contains less than 5% by weight of the initial mixture before heat treatment, residual additive formulation is negligible after heat treatment.

[0068] All of the metal compounds listed above have varying elemental compositions. However, because all metal compounds are reduced to their metallic state during the heat treatment step, it is convenient to simply refer to the metal content relative to the heat-treated material. Furthermore, because biochar is carbonized to approximately 99% carbon by weight during the heat treatment step, the composition of the post-heat-treatment mixture can be simply described as a binary mixture of metal and carbon. Therefore, for convenience, the carbon in the binary mixture is described as the fixed carbon in the biochar fraction of the mixture, and the metal in the binary mixture is described as the metal portion of the metal compounds present in the mixture.

[0069] A process of catalytic conversion can occur when elemental metals are exposed to a carbon source, such as char, under inert conditions at temperatures between about 400°C and about 3000°C. This can convert amorphous char to highly crystalline graphite over time. In doing so, it converts one allotrope of pure carbon to another. The extent and rate of graphite formation are highly dependent on the metal selected, while it is relatively insensitive to the initial choice of biomass, since the biomass is primarily carbonized. The exact mechanism of catalytic conversion is still unclear, but two plausible hypotheses have been proposed: dissolution-precipitation and carbide formation-decomposition. In the former, a carbon source is dissolved in the metal, and graphite spontaneously precipitates due to differences in their free energy or level of structural order. In the latter, unstable metal carbides are formed, which spontaneously decompose to yield graphite. The exact formation mechanism is not relevant to the present disclosure.

[0070] Depending on the biochar, metal compounds, liquid, and additive formulation selected, varying amounts of char can be converted to graphite. The properties of the resulting graphite can vary greatly depending on the biochar, metal compounds, liquid, and additive formulation selected. However, the relative percentages of carbon and metal, previously referred to as a binary mixture after heat treatment, have proven to be a key factor in determining the achieved conversion rate. The higher the percentage of metal, the higher the expected conversion rate due to the catalytic effect of the metal. To achieve an economical and efficient process, the conversion rate must be as high as possible without using excessive amounts of metal compounds. Control of the particle size and distribution of the metal compound particles is important to achieve this efficiency.

[0071] A second important property of the resulting graphite is its specific surface area (SSA). This property is a complex result of the uniformity of the distribution of metal compounds achieved in the mixture and the actual particle size distribution. Smaller particles tend to form smaller graphite crystals with low crystallinity, which results in a higher specific surface area; conversely, larger particles can produce larger crystals with high crystallinity and a lower specific surface area. In general, impregnation with a solution with dissolved solids can result in a small particle size distribution after drying, since the concentration is limited. On the other hand, solid-solid dry mixing at high loadings tends to result in larger particle sizes due to agglomeration effects.

[0072] While metal compounds can have a myriad of different compositions, and biochar can have a wide range of fixed and volatile carbon depending on pyrolysis conditions and temperature, the important ratio with respect to conversion is the ratio of metal present in the metal compounds to fixed carbon present in the char. Generally, metal-to-carbon mass ratios of about 0.25 to about 2.03 are used.

[0073] Based on these considerations, the overall composition can be determined to include a mixture of biochar, metal compounds, liquid, and an additive blend, where the mixture includes: (a) between about 1% and about 90% by weight of biochar; (b) between about 2% and about 90% by weight of metal compounds; (c) between 0.001% and about 83% by weight of liquid; and (d) between about 0.001% and about 5% by weight of the additive blend. Any weight percentage of these four components can be selected from these recited ranges, provided that the total adds up to 100%.

[0074] To more precisely describe the exact composition, specific metal compounds and char fixed carbon can be selected. For ease of specifying the range, the liquid component is omitted and the number of components is limited to three. While not limiting, iron oxide may be used with a char having 70% fixed carbon to obtain a dry mixture. Advantageously, the percentage of metal present in the iron oxide is approximately 70%, the same as the fixed carbon of the selected char. In this case, the effects cancel out, and the binary composition (metal-to-carbon mass ratio) described above translates directly to the desired composition (on a dry weight / weight basis) of the metal compound and char mixture. That is, the desired composition of the char to be mixed with the metal compound is between about 10% and about 80% by weight of the metal compound, more preferably between about 20% and about 67% by weight of the metal compound, with the char making up the difference.

[0075] The impact of additional additive formulations can be readily calculated based on a fixed percentage (dry wt / wt) of additive in the overall composition. The desired surfactant percentage is described as 0.001% to about 5% by weight (dry wt / wt) of the final mixture. Because of their low concentration, the additional components have a relatively small impact on the overall composition of the mixture. In the case of iron oxide, the desired composition (dry wt / wt) for the mixture may then be described as between about 9.5% and about 80% by weight of the metal compound, and between about 0.001% and about 5% by weight of the additive, with the balance being made up of char. More preferably, the desired composition (dry wt / wt) may be described as between about 19% and about 67% by weight of the metal compound, and between about 0.001% and about 5% by weight of the additive, with the balance being made up of char. The ranges for metal compound and char are specified at the minimum surfactant concentration that results in the broadest range of these components.

[0076] To account for other possible options for metal compounds, general ranges for the composition can be specified for the mixture (dry wt / wt basis) by slightly increasing both sets of ranges (base and preferred). In this case, the mixture (dry wt / wt basis) has (a) between about 9.5 wt% and about 90 wt% of the metal compound content, (b) between about 0.001 wt% and about 5 wt% of the additive blend components, and (c) a difference between about 90 wt% and about 5 wt% of the biochar. More preferably, the mixture (dry wt / wt basis) has (a) between about 19 wt% and about 82 wt% of the metal compound content, (b) between about 0.001 wt% and about 5 wt% of the additive blend components, and (c) a difference between about 81 wt% and about 13 wt% of the biochar. The ranges for the metal compounds and char are specified at the minimum surfactant concentration that provides the widest range for these components.

[0077] Based on the particle size achieved, the expected results for the various mixing approaches are summarized in Table 2. Table 2: Expected results

[0078] [Table 2]

[0079] The actual results observed, as detailed in Examples 1-3, are summarized in Table 3. Table 3: Observed results

[0080] [Table 3]

[0081] Despite only achieving a low metal-to-carbon ratio, the wet solution process surprisingly achieved high conversion rates to graphite. The higher-than-expected conversion rates are believed to be due to increased mobility of small metal particles relative to the larger particles produced during dry mixing. Conversely, dry solid mixing achieved only moderate levels of conversion, despite achieving higher catalyst loadings. Most surprisingly, the good distribution of finely divided metal compound particles achieved during wet slurry mixing allows for simultaneous achievement of high conversion rates and low surface area materials. This is unexpected based on previous observations of wet solution and dry mixing, where one property trades off against another, and thus both properties would be expected to be partially compromised. Instead, the use of additive blends with particulate material slurries results in optimized systems that maximize conversion to the desired low surface area product. Furthermore, material properties can be uniquely fine-tuned by directly controlling relative size and quantity. This is not possible with dissolved metal compounds, which are limited by their maximum solubility in a given liquid and the lack of particle size control. Thus, using the compositions of the present invention, a range of sizes between the fine distribution of a wet solution injection to the coarse particles of a dry solid mix can be achieved.

[0082] Example The examples described herein are provided for the purpose of illustrating particular embodiments of the present invention and are not intended to limit the present invention in any way. While the examples described herein are used to explain the method, it is understood that such details are solely for this purpose and that variations may be made therein by those skilled in the art without departing from the spirit and scope of the overall process.

[0083] The microwave laboratory setup used to fabricate one of the samples can be described as follows: A custom-designed microwave applicator is used to heat the sample to a temperature of ∼2000 °C at a maximum power input of 3 kW. The applicator arrangement is shown in Figure 1. The microwave generator delivers power to the applicator through a WR340 waveguide automatic matcher, a PTFE window, and a passive coupling element. The microwave generator is a 2.45 GHz YJ1600-based source (Sairem). The sample is placed in a crucible and positioned within the applicator at a predetermined height, usually on a "pillar," or stand, to obtain a specific radiation distribution (see Figure 2a). The unit is sealed and purged with nitrogen gas (99.9% purity) at a high flow rate for approximately 1 hour to establish an inert atmosphere, and then a lower purge flow rate is used to maintain the inert atmosphere. After this, power was gradually applied at a rate of 30 W / min to slowly heat the sample and quickly reach a steady state at the desired final power. A steady power setting was selected to achieve the desired temperature. The final power level was then held for a specific time depending on the desired result. As shown in Figure 2b, at this point the sample was red hot and the surface temperature of the crucible could be measured through the sight glass using a handheld pyrometer. The pyrometer readings showed a high level of variability and uncertainty, so the temperature range is reported. The power was then held constant for a given time frame, after which the generator was turned off and the resulting mixture sample was allowed to cool for removal. Alternatively, a conventional electric furnace equipped with a pyrometer was used to generate the remaining samples.

[0084] The analytical technique of X-ray diffraction (XRD) is used to assess the conversion rate of biochar to graphite. A fitting procedure is applied to the resulting XRD pattern or spectrum based on the expected composition of the mixture. A Rietveld program is used to model theoretical hexagonal and rhombohedral graphite cells. Amorphous carbon is modeled using a scaled lampblack reference pattern. In this way, the relative amounts of remaining amorphous carbon and formed crystalline carbon can be estimated to calculate the conversion rate from one to the other.

[0085] Example 1 Pine (Pinus radiata) sawdust (50 g) was hydrothermally treated with deionized water in an autoclave at a temperature of approximately 360°C for 20 minutes. The sample was allowed to cool and then filtered using a Buchner funnel. The resulting char was dried in a conventional oven. Dried char (10.1 g), with a carbon content of approximately 80%, was wet-impregnated with a solution of 8.2 g of manganese acetate (tetrahydrate) in 16 ml of water. The resulting mixture was placed in a crucible, dried in a conventional tray oven, and then transferred to a microwave applicator. Inert conditions were established, and the power was gradually increased to 1.3 kW at a rate of approximately 30 W / min. The temperature was measured to be between approximately 1400°C and 1600°C. The power was maintained constant for approximately 5 to 10 minutes, after which it was turned off. After cooling, the sample was sieved to less than 1 mm and then leached overnight with 500 ml of hydrochloric acid, followed by washing with deionized water and filtering through a Buchner funnel. The resulting graphite was analyzed using XRD (Bruker D8 Advance diffractometer using a 1 mm high parallel beam from a mirror with cobalt Kα radiation (weighted mean wavelength 0.1709026 nm)) and BET surface area analysis. The XRD spectrum is shown in Figure 3. The d spacing obtained from the 002 peak position is 0.3380 nm, and the crystallinity is 93.0%. The spectrum was analyzed using the procedure described, and the conversion of biochar to graphite was calculated to be 90.9%. The sample also had a 74.0 m 2For this sample, the binary composition of the mixture after heat treatment can be expressed as follows: (a) a carbon content of about 79% by weight; (b) Metal content of about 21% by weight.

[0086] For this sample, the composition (dry weight / weight basis) can be expressed as follows: (a) biochar content of approximately 63.6 wt.%; (b) Metal compound content of about 36.4 wt.%.

[0087] Example 2 Pyrolyzed hard charcoal (approximately 14 g) from Solid Energy, New Zealand, was crushed and sieved to less than 200 μm. The char, approximately 70% carbon, was mixed with approximately 21 g of iron oxide using dry blending. The resulting mixture was placed in a crucible and heated in a conventional electrically heated furnace (RD WEBB Aircooled Vacuum Furnace, model RD-G). Inert conditions were established by purging with argon gas (greater than 99.9%), and the temperature was increased at a rate of 10°C / min. The final temperature was set at 1750°C. The temperature was maintained constant for 180 minutes, after which the furnace was turned off. After cooling, the sample was sieved to less than 1 mm and then leached overnight with 500 ml of hydrochloric acid. It was then washed with deionized water and filtered through a Buchner funnel. The resulting graphite was analyzed using XRD (Bruker D8 Advance diffractometer using a 1 mm high parallel beam from a mirror with cobalt Kα radiation (weighted mean wavelength 0.1709026 nm)) and BET surface area analysis. The XRD spectrum is shown in Figure 4. The d spacing obtained from the 002 peak position is 0.3368 nm, and the crystallinity is 96.1%. The spectrum was analyzed using the procedure described and the conversion of biochar to graphite was calculated to be 60.9%. The sample was also analyzed using a 1.21 m 2 For this sample, the binary composition of the mixture after heat treatment can be expressed as follows: (a) a carbon content of about 40% by weight; (b) Metal content of approximately 60% by weight.

[0088] For this sample, the composition (dry weight / weight basis) can be expressed as follows: (a) biochar content of approximately 40% by weight; (b) metal oxide content of about 60 wt.%;

[0089] Example 3 Approximately 9.8 g of pyrolyzed hard charcoal from Solid Energy, New Zealand, was ground and sieved to less than 500 μm. The char, which had a carbon content of approximately 70%, was mixed with approximately 15.1 g of iron oxide using wet blending. The char was first mixed with 16 ml of water and 0.12 ml of a surfactant (75% water by weight, 25% ethanol by weight). The catalyst was then mixed with 16 ml of water and 0.55 ml of a surfactant (80% water by weight, 20% sodium dodecylbenzenesulfonate by weight). Both suspensions were mechanically stirred and homogenized using a blade mixer and ultrasonic horn. The two suspensions were then mixed, followed by mechanical stirring and homogenization. The product was then placed in a conventional tray oven and dried. The resulting powder was placed in a crucible and heated in a conventional electrically heated furnace (RD WEBB Aircooled Vacuum Furnace, Model RD-G). Inert conditions were established by purging with argon gas (greater than 99.9%), and the temperature was increased at a rate of 10°C / min. The final temperature was set at 1445°C. The temperature was maintained constant for 135 minutes, after which the furnace was turned off. After cooling, the sample was sieved to less than 1 mm and then leached overnight with 500 ml of hydrochloric acid, followed by washing with deionized water and filtering through a Buchner funnel. The resulting graphite was analyzed using XRD (Bruker D8 Advance diffractometer using a 1 mm high parallel beam from a mirror with cobalt Kα radiation (weighted mean wavelength 0.1709026 nm)) and BET surface area analysis. The XRD spectrum is shown in Figure 5. The d-spacing obtained from the 002 peak position is 0.3370 nm, and the crystallinity is 95.7%. The spectrum was analyzed using the procedure described and the conversion of the biochar to graphite was calculated to be 98.2%. The sample also had a 1.98 m 2 For this sample, the binary composition of the mixture after heat treatment can be expressed as follows: (a) a carbon content of about 39% by weight; (b) Metal content of about 61% by weight.

[0090] For this sample, the composition (dry weight / weight basis) can be expressed as follows: (a) biochar content of approximately 38.5 wt.%; (b) about 59.3 wt. % metal oxide content; (c) about 2.1 wt. % additive blend content.

[0091] A general outline of the overall process according to Example 3 is shown in Figure 6. Biomass (1) is converted to biochar (2), which is in particulate form. The biochar is then ground (3) and mixed with an additive blend to form a slurry. Metal oxides, which are in particulate form, are ground (3) and mixed with an additive blend to form a slurry. The two slurries are then mixed to form composition (4), which is optionally followed by drying. The composition of mixture (4) with respect to biochar, metal oxides, liquid, and additives is important in its ability to form graphite (5) with the desired properties at the desired conversion rate during heat treatment.

Claims

1. 1. A composition comprising a mixture of biochar, a metal compound, a liquid, and an additive blend, the mixture comprising: (a) between about 1% and about 90% by weight of biochar; (b) between about 2% and about 90% by weight of a metal compound; (c) between 0.001% and about 83% by weight of a liquid; and (d) between about 0.001% and about 5% by weight of an additive blend, wherein the additive blend is selected from one or more of a surfactant, a binder, a dispersant, a rheology modifier, a wetting agent, a defoamer, and any combination thereof.

2. 10. The composition of claim 1, wherein the liquid and the metal compound are selected such that the metal compound has minimal solubility in the liquid when the composition is used.

3. 3. The composition of claim 1, wherein the liquid is water.

4. The composition of any one of claims 1 to 3, wherein the metal compound comprises a transition metal.

5. 5. The composition of claim 4, wherein the transition metal is selected from chromium, zirconium, molybdenum, ruthenium, rhodium, palladium, silver, cadmium, zinc, copper, nickel, cobalt, iron, manganese, chromium, vanadium, or any combination thereof.

6. The composition according to any one of claims 1 to 5, wherein the metal compound is derived from the thermal decomposition of an organic or inorganic metal salt.

7. 7. The composition of any one of claims 1-6, wherein the mixture comprises, on a dry weight / weight basis (excluding liquid), (a) between about 9.5% and about 90% by weight of the metal compound, (b) between about 0.001% and about 5% by weight of the additive blend, and (c) between about 5% and about 90.5% by weight of the biochar.

8. 8. The composition of claim 7, wherein the mixture more preferably comprises, on a dry weight / weight basis (excluding liquids), (a) between about 19% and about 82% by weight of the metal compound, (b) between about 0.001% and about 5% by weight of the additive blend, and (c) between about 13% and about 81% by weight of the biochar.

9. The composition according to any one of claims 1 to 8, wherein the metal compound is a transition metal oxide.

10. 10. The composition of claim 9, wherein the transition metal oxide is selected from oxides of iron, copper, nickel, manganese, vanadium, tin, chromium, zinc, titanium, and cobalt, or any combination thereof.

11. The composition of claim 10 , wherein the transition metal oxide comprises iron oxide.

12. 12. The composition of any one of claims 1-11, wherein the mixture comprises, on a dry weight / weight basis: (a) between about 9.5% and about 80% by weight of iron oxide; (b) between about 0.001% and about 5% by weight of the additive blend; and (c) between about 20% and about 90.5% by weight of biochar, the biochar having a fixed carbon content of about 70%.

13. 13. The composition of claim 12, wherein the mixture (on a dry weight / weight basis) more preferably comprises: (a) between about 19% and about 67% by weight of iron oxide; (b) between about 0.001% and about 5% by weight of the additive blend; and (c) between about 33% and about 81% by weight of biochar, the biochar having a fixed carbon content of 70% or greater.

14. The composition of any one of claims 1 to 13, wherein the biochar is produced by thermally treating woody biomass.

15. 15. The composition of any one of claims 1 to 14, wherein the biochar in the mixture is in particulate form.

16. 16. The composition of claim 15, wherein the biochar has an initial particle size of less than about 50 mm.

17. The composition of any one of claims 1 to 16, wherein the metal compound in the mixture is in particulate form.

18. 18. The composition of any one of claims 1 to 17, wherein the metal compound and the biochar are both in particulate form.

19. 19. The composition of claim 17 or 18, wherein the metal compound has an initial particle size of less than about 5 mm.

20. 20. The composition of any one of claims 1-19, wherein the biochar has an initial particle size of less than about 50 mm and the metal compound has an initial particle size of less than about 5 mm.

21. 21. The composition of any one of claims 15-20, wherein the biochar has a particle size of less than about 800 μm.

22. 22. The composition of claim 21, wherein the particle size of the biochar is less than about 500 μm.

23. 23. The composition of claim 21 or 22, wherein the particle size of the metal compound is less than about 100 μm.

24. 24. The composition of claim 23, wherein the particle size of the metal compound is less than about 75 μm.

25. 25. The composition of any one of claims 1 to 24, wherein the additive formulation comprises two or more of a surfactant, a binder, a dispersant, a rheology modifier, a wetting agent, a defoamer, and any combination thereof.

26. The additive formulation may be selected from the group consisting of acResin®, ACRODUR®, ACROFLOR®, ACRONAL®, AEROSOL C-61, AG 6202, ALCOSPERSE 175, ALMIPAL P, Amidex®, aminoethylethanolamine, ammonium fluoride, AMMONYX M, AQACell®, Aquatreat BW30, Arkopal, Armac®, Armeen®, and Armid®. O, Attagel®, Aziridine, BASONAT® Polyisocyanate, Bronidox, BTBAB-90, BTBAC-50, Bteac-50, BTMAC-50, BTMAH-40, BUTOFAN® Styrene-Butadiene Binder, BUTONAL® Styrene-Butadiene Binder, Butyl Stearate, Calcium Stearate, Darvan®, Dispex®, Dodecandioic Acid, DYSPERSE®, EDAPLAN®, EFKA®, ENORDET, Ethoduomeen T / 25, EURAMAAT, EUR-AMID, EURANAAT, EURASOL, EUROGLYC, EUROQUAT, EUROWET, EUROXIDE, EXOdis PC30, FOAMASTER MO 2133, FOAMSTAR®, Heliogen Blue D 7079, HYDROPALAT®, JONCRYL®, Lauryl Alcohol, Reparl MSC, Reparl NTD, Magna Surf®, MERPOL SE, METOLAT®, NANSA, Oleamide, Oleic Acid, Passatell M-182 (2-798), PEG-400, Pentaerythritol Oleate, Poise 520, Poise 530, Polyamide, Polyester, POLYFON H, Polyglycol, Polyman®, Polymerizable Additive, Potassium Soyate, Quickpearl PK3, REAX®, REWOCID DU185 SE, Rewopol SB L 203, Rheovis®, ROKAmer1010 / 50, Schercomid®, SDS, Sibet®, Sico 50BC, Sidos 70, Sodium Dodecylbenzenesulfonate, Sodium N-Hexadecanoyl-L-alanine, Sodium Silicate, Sorbitan Monooleate, Sorbitan Monopalmitate, Steamcare B12, Stearyl Chloride, STYROFAN®, SugaDet APG-10, Sulfoccinate LSS, Sulfochem®, Sulfated Butyl Oleate, Sunnol®, SURFACARE O ACID, TBAH-40, TBAHS-50, Tensol® DDM, TERGITOL®, TLMAC-30, TMAC-100 26. The composition of claim 25, comprising an additive selected from one or more of ARQUAD 41-100, Tomamine Amphoteric 12, triethanolamine, triethylbenzylammonium chloride, TWEEN 80, UFACID K, Vitec®, YB-0100, YB-150, YB-191, YB-2000, YB-904, YBASD-200, and any combination thereof.

27. A method comprising heat treating the composition of any one of claims 1 to 26 to a temperature above the reduction temperature of said metal compounds, thereby reducing said metal compounds to elemental metals or alloys.

28. 28. The method of claim 27, wherein the heat treatment results in the conversion of amorphous biochar to crystalline graphite.

29. 29. The method of claim 27 or 28, wherein the conversion of amorphous char to crystalline graphite formed by said heat treating said mixture is greater than about 50%.

30. 30. The method of claim 29, wherein the conversion to graphite is greater than about 75%.

31. 31. The method of any one of claims 27 to 30, wherein the crystalline graphite formed by the heat treatment of the mixture has a crystallinity of greater than about 90%.

32. 32. The method of claim 31 , wherein the crystallinity of the crystalline graphite is greater than about 95%.

33. 33. The method of any one of claims 27 to 32, wherein the specific surface area of the graphite formed by the heat treatment of the composition, as determined above, is less than about 50 m / g.

34. 34. The method of claim 33, wherein the specific surface area of the graphite is less than about 30 m / g.

35. A method for producing a composition according to any one of claims 1 to 26, comprising the steps of: i) heat treating biomass in particulate form at a temperature between about 200°C and about 1000°C under inert conditions to form granular biochar; ii) grinding the biochar to obtain a particle size of less than about 800 μm, more preferably less than 500 μm; iii) milling a suitable metal compound to obtain a particle size of less than about 100 μm, more preferably less than 75 μm; iv) combining the resulting biochar with the metal compound, liquid, and additive blend; v) heating the mixture to between about 400°C and about 3000°C under inert conditions to produce graphitic carbon.

36. 36. The method of claim 35, wherein the biomass is heat treated in water in a hydrothermal step to produce the biochar.

37. 36. The method of claim 35, wherein the biomass is heat treated under inert conditions in a dry pyrolysis step to produce the biochar.

38. 38. The method of any one of claims 35 to 37, wherein the biomass is a forestry residue.

39. 39. The method of claim 38, wherein the forestry residue is sawdust.

40. 38. The method of any one of claims 35 to 37, wherein the biomass is lignocellulosic biomass or a lignin derivative.

41. 41. The method of any one of claims 35 to 40, wherein the biomass is wood chips or any other wood-based material.

42. The method of any one of claims 35 to 41, wherein the liquid is water.

43. A method according to any one of claims 35 to 42, wherein the liquid and the metal compound are selected such that, in use, the metal compound has minimal solubility in the liquid.

44. 44. The method of any one of claims 35 to 43, wherein in step iv), the metal compounds are combined with the biochar by wet mixing together with an additive formulation in a mixer.

45. 45. The method of any one of claims 35 to 44, wherein in step iv), the metal compounds are mixed with the biochar by wet grinding together with an additive blend in a mill.

46. 46. The method of any one of claims 35 to 45, wherein the additive formulation for the mixed slurry comprises two or more of a surfactant, a binder, a dispersant, a rheology modifier, a wetting agent, an antifoaming agent, and any combination thereof.

47. 45. The method of any one of claims 35 to 44, wherein in step iv) the water granular slurry is formed by mixing the metal compound with the additive blend in water using a mixer to produce a granular metal compound slurry.

48. 48. The method of any one of claims 35 to 44 and 47, wherein in step iv), a granular aqueous slurry is formed by mixing the biochar with an additive blend in water using a mixer to form a granular biochar slurry.

49. 49. The method of claim 47 or 48, wherein the additive formulation is selected from binders, dispersants, rheology modifiers, wetting agents, antifoaming agents, and any combination thereof.

50. 50. The method of any one of claims 47 to 49, wherein the particulate metal compound slurry is combined with the particulate biochar slurry and then mixed together in a mixer.

51. 51. The method of any one of claims 35 to 50, wherein the mixture obtained in step (iv) is heated in step (v) to between about 400°C and about 3000°C under inert conditions using a controlled atmosphere oven, furnace or other heating device to produce graphitic carbon, the heat treatment temperature being higher than the reduction temperature of the selected metal compounds such that they are reduced to their elemental metal or alloy state.

52. 52. The method of any one of claims 35 to 51, wherein the metal compound is a transition metal oxide.

53. 53. The method of claim 52, wherein the transition metal oxide is selected from oxides of iron, copper, nickel, manganese, vanadium, tin, chromium, zinc, titanium, and cobalt, or any combination thereof.

54. 54. The composition of claim 53, wherein the transition metal oxide comprises iron oxide.

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