Solid carbon products and methods of producing solid carbon

Abstract

A method of forming a solid carbon product includes contacting a reaction stream comprising, a carbon oxide, and a hydrocarbon with a catalyst, forming solid carbon and gaseous products in response to the contacting, and separating the solid carbon from the gaseous products to form a solid carbon product. The solid carbon comprises a portion of the catalyst. The solid carbon material include solid carbon, and a metal selected from the group consisting of a Group VI element, a Group VII element, a Group VIII element, a Group IX element, and a Group X element. The metal in the material is encompassed by the solid carbon.

Description

SOLID CARBON PRODUCTS AND METHODS OF PRODUCING SOLID CARBONCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application claims priority to U.S. Provisional Application No. 63 / 639,302 filed on April 26, 2024 and entitled, “SOLID CARBON PRODUCTS AND METHODS OF PRODUCING SOLID CARBON'’, the entire disclosure of which is incorporated herein by reference.STATEMENT REGARDING GOVERNMENTALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] None.BACKGROUND

[0003] Industrial hydrogen and carbon can be produced primarily by reacting hydrocarbon feedstocks (e.g. CH4, naphtha, biomass, coal, etc) using pyrolysis (e.g., in the absence of oxygen) or with oxy gen-containing species (e.g. O2, H2O, CO2) to produce solid carbon along with a mixture of H2, CO2, and H2O. Carbon produced using these techniques can take a variety of forms, with the specific carbon properties depending on the process used to produce the carbon.SUMMARY

[0004] In some embodiments, a material comprises solid carbon, and a metal selected from the group consisting of a Group VI element, a Group VII element, a Group VIII element, a Group IX element, and a Group X element. The metal in the material is encompassed by the solid carbon.

[0005] In some embodiments, a method of forming a solid carbon product comprises contacting a reaction stream comprising, a carbon oxide, and a hydrocarbon with a catalyst, forming solid carbon and gaseous products in response to the contacting, and separating the solid carbon from the gaseous products to form a solid carbon product. The solid carbon comprises a portion of the catalyst.

[0006] In some embodiments, a method of separating carbon from a gas stream comprises contacting a gas stream comprising solid carbon particles with an aqueous fluid, wetting the solid carbon particles with the aqueous fluid, separating the solid carbon particles from the aqueous fluid, and recovering the solid carbon particles as a product stream.

[0007] These and other features will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings and claims.BRIEF DESCRIPTION OF THE DRAWINGS

[0008] For a more complete understanding of the present disclosure, reference is now made to the following brief description, taken in connection with the accompanying drawings and detailed description:

[0009] FIG. 1 schematically illustrates a carbon formation system according to some embodiments.

[0010] FIG. 2 schematically illustrates another carbon formation system according to some embodiments.

[0011] FIG. 3 is a graph show ing the thermal diffusivity results of the solid carbon product.

[0012] FIG. 4 is a graph show ing the thermal conductivity results of the solid carbon product.

[0013] FIG. 5 is a graph showing the heat capacity results of the solid carbon product.

[0014] FIG. 6 is a graph showing the conductance results of the solid carbon product.

[0015] FIG. 7 is a graph showing the conductivity results of the solid carbon product.

[0016] FIG. 8 is a graph showing the resistivity results of the solid carbon product.

[0017] FIG. 9 is a graph showing the density results of the solid carbon product.

[0018] FIG. 10 is a graph showing the graphitization results of the solid carbon product.

[0019] FIG. 11 is a graph showing the x-ray diffraction pattern of the solid carbon product.

[0020] FIG. 12 is a graph showing the particle size distribution results of the solid carbon product.

[0021] FIG. 13 is a graph showing the surface area results of the solid carbon product.

[0022] FIG. 14 is a graph showing another x-ray diffraction pattern of the solid carbon product.

[0023] FIG. 15 is a chart showing the contact angle results of the solid carbon product.

[0024] FIG. 16 is a graph showing the compaction test results of the solid carbon product.

[0025] FIG. 17 is a graph showing the angle of repose of the solid carbon product.DETAILED DESCRIPTION

[0026] Disclosed herein are systems and processes for forming solid carbon products having unique properties. The carbon can result from the decarbonization of fuel sources such as hydrocarbons, which can help io reduce carbon dioxide emissions. The resulting carbon properties can allow the carbon to be easily separated from the resulting product stream and allow for various uses of the carbon as a separate product.

[0027] A system 100 for C, H2, and H2O formation from a feed containing a hydrocarbon, and carbon oxides (e.g., CO and / or CO2) is shown in FIG. 1. In some aspects, an optional stream of O2 can be present in the reactor, though in other aspects, no oxygen is added. As illustrated, the system 100 contains a carbon formation reactor 110 fed by a stream 106 comprising ahydrocarbon, an optional stream 102 comprising oxygen, and a stream 104 comprising COx. In some aspects, one or more of the streams can comprise some amount of water in the form of steam, and / or the oxygen can be used to react with a portion of the hydrocarbon to form COx and water. The hydrocarbon can comprise any hydrocarbon including light alkanes such as methane, ethane, natural gas, as well as other gaseous, liquid, and solid hydrocarbons (e.g. ethanol, crude oil, biomass, naphtha, etc.). In some aspects, a gasification reactor can be used to convert one or more hydrocarbon containing species into a gaseous stream. In some aspects, the hydrocarbon can be provided as a fluidized solid or other form.

[0028] Stream 102 can optionally comprise any oxygen containing stream such as air or an oxygen enriched stream. An oxygen enriched stream refers to any stream having an oxygen concentration greater than the atmospheric concentration of oxygen. The oxygen stream 102 can be obtained at a desired purity from an oxygen storage tank, or via an oxygen enrichment process, for example, the separation of air into nitrogen and oxygen, such as pressure swing adsorption (PSA), vacuum swing adsorption (VS A), or cryogenic separation techniques. The oxygen in the oxygen stream 102 may have at least about 70 vol%, at least 80 vol%, or at least 90 vol % oxygen (e.g.. 90, 91, 92, 93, 94, 95, 96. 97. 98. 99. 99.1, 99.2, 99.3, 99.4, 99.5. 99.6. 99.7. 99.8, 99.9, or 100 vol % oxygen). While shown as three separate streams in FIG. 1, the components can be provided in a single or otherw ise combined stream. A recycle gas stream can also be combined with the inlet stream as described in more detail herein.

[0029] The feed stream(s) can be preheated in preheater 108 and introduced into the carbon formation reactor 1 10 along with a catalyst stream 1 12 comprising a catalyst. The individual feed streams may be at any suitable pressure and temperature, and one or more heat exchangers (e.g., preheater 108, etc.) can be used to adjust the temperature of the corresponding stream. The combined stream may have a pressure between about 1 bar to about 50 bar, or between about 5 bar and about 20 bar. The preheater 108 can be used to heat the incoming combined stream to a temperature between about 200°C to about 700°C, or between about 250°C to about 400°C, which can be the inlet temperature to the carbon formation reactor 110.

[0030] Within the carbon formation reactor 110, carbon forms along with H2 and H2O. V arious reactions can occur that can result in the formation of solid carbon and other reaction products comprising hydrogen, water, CO, and CO2 according to the following reactions:2CO C + CO2CO2 + CH42CO + 2H2H2O+ CH4 CO + 3H2O2 + 2CH 2CO + 4H2CO + H2C + H2OCO + H2O CO2 + H2

[0031] The reactions occurring are both exothermic and endothermic. The reaction conditions wi thin the carbon formation reactor 110 may include a pressure of between about 1 bar to about 50 bar, or between about 1 bar to about 20 bar, a temperature of about 400°C to about 1000°C, or between about 500°C to about 750°C. The temperature within the reactor may be maintained by providing an adiabatic reactor vessel and / or providing the reactants at the desired temperature into the reactor to maintain the temperature within the desired temperature range. The carbon formation reactor 110 can take a variety of forms such as a fixed bed reactor, a fluidized bed reactor, a moving bed reactor, or the like.

[0032] The reactor can use a catalyst to promote the reactions and the formation of solid carbon. The catalyst material can include any material suitable for catalyzing the formation of the solid carbon material from the carbon oxide and the gaseous reducing material. As an example, the catalyst material may be an element of Group VI, Group VII, Group VIII, Group IX, or Group X of the Periodic Table of Elements (e.g., iron, nickel, molybdenum, platinum, chromium, cobalt, tungsten, etc.), an actinide, a lanthanide, oxides thereof, alloys thereof, or combinations thereof. Any metal known to be subject to metal coking may also be suitable for use as the catalyst material.

[0033] The catalyst material may be provided within the carbon formation reactor 110 (e.g., within the reaction chamber) as one or more solid structures (e.g.. a particle, a wafer, cylinder, plate, sheet, sphere, pellet, mesh, fiber, etc.), and / or as at least a partial coating on another structure (e.g., particles of the at least one material deposited on a structure, such as a wafer, cylinder, plate, sheet, sphere, mesh, pellet, etc.) within the reactor vessel. In some embodiments, the catalyst material may be provided within the reactor as a plurality of particles or particulates. The catalyst material may be stationary (e.g. , as a catalyst bed) or mobile (e.g., as a fluidized bed) within the reactor. In some embodiments, a portion of the catalyst material may be mobile within the reactor and another portion of the catalyst material may be stationary within the reactor. In addition to the catalyst, one or more inert particles may optionally be present in some embodiments.

[0034] As an example, the catalyst for the carbon formation reaction can include an iron-based catalyst. While not intending to be limited by theory, a dissociated carbon (e.g., a methanedissociated in contact with the iron, and / or one or more carbon oxides within the reactor) can contact the iron (e.g.. a ferrite) within the catalyst to form an iron carbide. The iron carbide can then dissociate to reform the ferrite along with a layer of carbon (e.g. , graphite, etc.) on the ferrite. The process can continue and result in the buildup of carbon layers on the ferrite, where the reaction rate can decrease as the thickness of the carbon layer on the iron builds due to increased diffusion resistance to the reactive iron core. The catalyst can then be encompassed or surrounded by the carbon such that the reactant gases can still diffuse to the catalyst surface to continue to form and grow the solid carbon. The catalyst may then deactivate upon the buildup of a sufficient carbon layer. For example, the catalyst may deactivate when the reactant gases can no longer diffuse through the solid carbon to the catalyst.

[0035] The formation of the solid carbon then occurs on or around the catalyst (e.g., encompassing or surrounding the catalyst) such that the removal of solid carbon from the reactor vessel (e.g., using a separator such as a cyclone, settling chamber, etc.) can also result in the removal of the catalyst from the reactor. As a result, a small amount of catalyst may be introduced into the carbon formation reactor 110 along with the reactants while a corresponding amount of catalyst may be removed with the solid carbon. In some aspects, the amount of catalyst added into the reactor may have a mass ratio of catalyst to reactants of between about 0.0001 :1 to about 1 : 1 , or between about 0.001 : 1 to about 0.1: 1.

[0036] As shown in FIG. 1. the catalyst stream 112 comprising the catalyst may be introduced into the carbon formation reactor 110. The catalyst may comprise an oxide, and the resulting oxygen in the oxide as well as the oxygen in the COXmay form some amount of water in the gaseous product stream from the carbon formation reactor 110. The products from the carbon formation reactor can then include the gaseous product stream comprising CO, H2O, H2, CO2, and some amount of unreacted hydrocarbons, while the solid product stream can comprise solid carbon along with the catalyst or a portion of the catalyst. The solid product stream can be removed from the carbon formation reactor 110 as a separate product stream from the gaseous product stream and removed from the system 100.

[0037] The carbon formation reactor 110 can form solid carbon that can be removed as a solids stream and a gaseous stream comprising CO. H2O. H2. CO2. and potentially some unreacted hydrocarbon. The reaction can result in an outlet temperature in the range of 400-750°C. The solids stream can comprise predominantly carbon with some amount of the catalytic material included. In some aspects, the mass ratio of the solid carbon to the catalytic material can be in the range of about 500: 1 to about 1: 1, or in a range of about 100:1 to about 5: 1.

[0038] FIG. 2 illustrates an embodiment of a carbon formation reactor 200. As shown, the solid catalyst 206 can be introduced into the process as a solids stream 204. Within the carbon formation reactor 200, the solid catalyst 206 can form a bed where the components of the feed stream 202 can react to form solid carbon on the solid catalyst 206. A portion of the solid carbon 208 can be removed from the solid catalyst 206 and entrained with the gas stream 210 out of the reactor. The solid carbon 212 can then be separated in one or more downstream units.

[0039] The feed stream 202 can comprise any of the feed streams passing to a carbon formation reactor as described herein. The feed stream can comprise carbon monoxide and hydrogen, and optionally, carbon dioxide and / or a hydrocarbon including any of those described herein. In some aspects, additional, optional components such as oxygen and / or water may also be present in the feed stream 202. In some aspects, the ratio of hydrogen to carbon monoxide by volume in the feed stream 202 can be between about 1.5: 1 to about 6: 1. In some aspects, the hydrogen gas to carbon monoxide ratio (H2 / CO) in the feed stream 202 can be at least about 0. 1, at least about 0.25, at least about 1, or at least about 1.5, and / or the hydrogen gas to carbon monoxide ratio (H2 / CO) in the feed stream 202 can be less than about 10. less than about 8, less than about 6, less than about 4, or less than about 2. When present, the hydrocarbon may be present in an amount of between about 1% to about 50% by volume of the combined stream 202, or at least about 10% by volume of the combined stream 202. In some aspects, the hydrogen to carbon dioxide mole ratio (H2 / CO2) in the feed stream can range from about 10 to about 40, or between about 20 to about 35. In some aspects, the hydrogen to hydrocarbon mole ratio (Fb / hvdrocarbons such as methane) in the feed stream can range from about 0.5 to about 4, between about 1 to about 3, or between about 1.5 to about 2.5.

[0040] The catalyst introduced into the carbon formation reactor 200 in solids stream 204 can include any of the catalyst(s) described with respect to FIG. 1. In some aspects, the catalyst may be unsupported such that the catalytic component is not placed or supported on another material.

[0041] Within the carbon formation reactor 200, the catalyst can take a variety of forms such as a fixed bed reactor, a fluidized bed reactor, a spouting bed reactor, a moving bed reactor, circulating fluidized bed, or the like. The carbon formation reactor can operate under any of the conditions such as temperature, pressure, and residence time as described herein. For example, the reaction may occur at a temperature between about 400 °C and about 1000 °C, or betw een about 550 °C to about 900 °C, or between about 650 °C to about 800 °C, and the reaction may occur at a pressure betw een about 1 and 40 bar, between about 1 and 20 bar, or between about 5 and 15 bar. During the reaction, solid carbon may be formed on the catalyst particles and forma layer of solid carbon. Additional reaction products such as hydrogen and other products can be produced.

[0042] In some aspects, the catalyst particles can form a mobile bed such as a fluidized bed or a spouting bed in which the particles move relative to each other. For example, at least about 20%, at least about 40%, or at least about 50% of the solid material in the reactor may be fluidized by the gas phase. The relative movement of the catalyst particles can cause attrition of the catalyst as well as the carbon formed on the catalysts. Additionally, the particles can disintegrate by metal dusting (CO reduction and Boudouard reactions) heterogeneous chemical reactions. In this process, a fresh catalyst particle can have an initial diameter. As the reaction progresses, solid carbon can be formed on the catalyst as an outer layer while disintegrating the catalyst. As the catalyst particles move relative to each other, attrition of the catalyst and the solid carbon can occur. The overall process can result in a decrease in the average diameter of the catalyst particle, and as the process continues, the catalyst particle may eventually have a decreased diameter reaching a certain minimum size, at which time the catalyst particle may be considered to be expended.

[0043] The relative size differences between the catalyst particles as disintegration and attrition occurs and the particulates removed from the catalyst particles can be used to selectively remove the solid products from the reactor using the feed and product gas flow rates to fluidize and entrain the product particulates. The solid products can be removed continuously or in a semibatch or batch process. For example, the gas velocity through the reactor could periodically be increased to remove the solid particulates in a batch or semi-batch manner, or the gas flow rate could be selected along with the geometry of the reactor to have a continuously entrained stream of particulates of a desired size. While not shown, a solid outlet may also be present in the reactor to remove a portion of the solid product and / or catalyst particles from a lower portion of the reactor.

[0044] In addition to the gas phase flow rate, the density of the solid carbon and catalyst particulates and the geometry of the carbon formation reactor can be used to selectively remove particulates having an average diameter below a certain size from the carbon formation reactor. In some aspects, the internal diameter of the reactor can increase above the bed of particulates (i.e. the freeboard) to provide a lower gas velocity to allow larger particles to settle back to the upper surface of the bed. In some aspects, the carbon formation reactor can have a conical or increasing diameter towards an upper end of the reactor. In some aspects, the internal diameter of the carbon formation reactor 200 can increase to a final diameter and then maintain the diameter to an upper end of the vessel. The shape and rate of expansion of the internal diametercan be selected to provide for a desired residence time of the solid particles entrained in the gas phase to allow proper size selection of the particles remaining in the gas phase and being removed from the carbon formation reactor in gas stream 210.

[0045] The ability to remove the particulates can allow the solid products and a portion of the catalyst material to be removed from the carbon formation reactor based on size and density differences of the particles resulting from the disintegration via heterogeneous chemical reaction and natural attrition of the particles moving relative to each other. In some aspects, the solids entrained in the gas stream 210 can have a Sauter mean diameter that is at least about 2 times smaller than the Sauter mean diameter of the solid catalyst particles in the carbon formation reactor. For example, the catalyst entering the carbon formation reactor 200 in solids stream 204 can have a Sauter mean diameter between about 50 and 500 m. or betw een about 100 and 300 pm. The solid phase comprising the catalyst and the solid carbon on the catalyst particles within the carbon formation reactor can have a Sauter mean diameter between about 20 and 400 pm, or between about 50 and 250 pm. The solid particulates, including solid carbon particulates and / or solid catalyst particulates resulting from chemical disintegration or attrition of the catalyst and solid carbon on the catalysts, can have a Sauter mean diameter between about 0.01 pm and 100 pm, or between about 0. 1 pm and about 1 pm.

[0046] The relative amount of carbon removed in the particulate stream can be larger than the amount of catalyst removed. For example, the process may result in a solid phase being removed from the carbon formation reactor as an entrained stream, where the solid phase can include the solid carbon particulates and the solid catalyst particulates. The solid phase removed from the reactor can be more than about 50 wt.% carbon, or greater than about 80 wt.% carbon. Within the reactor, the solid phase that includes the solid carbon particulates, and the solid catalyst particulates, and the solid catalyst particles having carbon formed thereon during the reaction. The solid phase within the reactor can comprise less than about 50 wt.% carbon, less than about 30 wt.% carbon, or less than about 20 wt.% carbon.

[0047] Once removed from the carbon formation reactor 200 in the product stream 210, the entrained solids can be separated using any of the separation devices described herein such as a cyclone, bag house, filter, or the like. The resulting solids stream from the separator can then be further processed. It is expected that some amount of the solids in the solids stream can comprise the catalytic material, and it may be useful to recycle or return at least a portion of the catalytic material into the carbon formation reactor 200 to allow for further formation of the solid carbon. In order to return the solid catalyst, at least a portion of the solids leaving the carbon formationreactor 200 may be separated and returned to the carbon formation reactor 200 as part of the solids stream 204 and / or as a separate solids inlet stream into the carbon formation reactor.

[0048] Size selection can be used to provide the portion of the separated solids returned or recycled to the carbon formation reactor. In some aspects, the portion returned to the carbon formation reactor can have a larger Sauter mean diameter than the rest of the solids in the product stream leaving the carbon formation reactor. For example, the portion of the solid products returned to the carbon formation reactor may represent the largest 10%. the largest 20%, or the largest 30% of the solids removed from the carbon formation reactor as measured by the average Sauter mean diameter of the solids in the product stream. The large particles may also represent a portion of the solids having a higher mass percentage of catalyst. In some aspects, the portion of the solids stream returned or recycled to the carbon formation reactor can have a higher catalyst to carbon mass ratio than the rest of the solid product stream.

[0049] The carbon formation reactor 200 can be used to perform any of the carbon formation reactions as described herein. In some aspects, the carbon formation reactor 200 can be used to react a feed stream comprising hydrogen and carbon monoxide to form a gaseous product comprising hydrogen, carbon monoxide, and carbon dioxide as well as a solid carbon product stream. A solid phase can be present in the reactor during the reaction that comprises a solid catalyst having the solid carbon product formed thereon. In some aspects, the catalyst can form a fluidized bed. Any of the catalyst described herein can be used, and in some embodiments, the catalyst can comprise iron, an iron oxide, or an iron carbide (e.g., FesC). The solid phase comprising the solid catalyst and the solid carbon can have less than about 50 wt.% carbon. The movement of the solids in the fluidized bed can result in the formation of separate particulates of carbon and the solid catalyst. The particulates can be entrained in the gas phase leaving the carbon formation reactor. The solids leaving the carbon formation reactor can be at least about 50 wt.% carbon, and / or the solids can have a Sauter mean diameter of at least about 50% smaller than the solid phase particles in the fluidized bed that are not entrained in the gas phase.

[0050] The resulting solid carbon product can have unique properties based on the use of the carbon formation reactor and reaction conditions. For example, the presence of the catalyst in the carbon product can produce a unique solid carbon product. In some aspects, the solid carbon can comprise a mass ratio of the solid carbon to the catalytic material can be in the range of about 500:1 to about 1:1, in a range of about 100:1 to about 3: 1, or in a range of about 75: 1 to about 5:1.

[0051] In some aspects, the solid carbon can have a heat of combustion between about 400 kJ / mol and about 300 kJ / mol, or between about 398 kJ / mol and about 310 kJ / mol, or betweenabout 396 kJ / mol and about 330 kJ / mol. The heat of combustion may vary based on the catalyst loading in the solid carbon.

[0052] The thermal properties of the solid carbon can vary with temperature. In some aspects, the thermal diffusivity can have a value in a range from about 0.6 to about 0.30 mm2 / s, or about 0.55 to about 0.33 mm2 / s over a temperature from about 25 °C to about 800 °C. In some aspects, the thermal conductivity can vary from about 0.30 to about 0.60 W / mol-K, or about 0.31 to about 0.55 W / mol-K over a temperature from about 25 °C to about 800 °C. In some aspects, the heat capacity can vary from about 15 to about 35 J / mol-K, or between about 18 to about 30 J / mol-K over a temperature from about 250 °C to about 750 °C.

[0053] The electrical properties of the solid carbon can vary based on the density of the carbon product. In some aspects, the resistivity of the solid carbon can range from about 7 to about 80 *cm, from about 9 to about 70 *cm, or from about 10 to about 66 *cm. In some aspects, the conductance of the solid carbon can range from about 0.2 Siemens (S) to about 5.5 S, or from about 0.3 S to about 4.9 S, or from about 0.5 S to about 4.5 S. In some aspects, the bulk density of the solid carbon can range from about 0.55 g / cm3to about .95 g / cm3. or between about 0.58 g / cm3to about 0.92 g / cm3. While the bulk density may be below about 1 g / cm3, the individual carbon particles may have a density of greater than 1 g / cm3due to the presence of the catalyst. A pressure of betw een about 0 to about 0.06 MPa can be used to compress the solid carbon between the lower range of densities and the upper range of densities.

[0054] In some aspects, the particle size of the solid carbon generally varies between about 2 pm and about 210 pm, or betw een about 3 pm to about 150 pm. The Sauter mean diameter of the resulting particles can be between about 30 pm to about 250 pm, or between about 45 pm to about 200 pm. For the majority of the particles, the increased weight percentage of the catalyst results in larger particle sizes.

[0055] In some aspects, the surface area of the carbon can vary from about 30 m2 / g to about 40 m2 / g. In some aspects, the crystallinity of the solid carbon can be between about 30% to about 50%. where an increased amount of the catalyst in the solid carbon can result in a lower crystallinity.

[0056] In some aspects, the solid carbon product can be hydrophilic. For example, the contact angle of the solid carbon (e.g., the angle formed betw een a surface and an outer surface of a water droplet on the surface) can be less than 90 degrees, less than about 80 degrees, or less than about 70 degrees, or less than about 60 degrees.

[0057] In some aspects, the solid carbon product can be treated to reduce the amount of catalyst present in the solid carbon. Exemplary processes can include the use of acid washes to solubilize the catalysts (e.g., iron in the carbon). For example, an acid such a hydrochloric, nitric, or sulfuric acid can be used to remove a portion of the catalyst from the solid carbon. Other processes can include reach on with compounds that can increase the volatility of the catalytic material. For example, various halogens can be reacted with the carbon to reduce the melting point and / or vaporization temperature of the catalyst. As a specific example, iron can be reacted with a halogen such as chlorine to form iron chloride that can be vaporized to remove the iron chloride from the carbon. The use of these processes can result in a controlled loading of the catalytic material in the solid carbon product.

[0058] In some aspects, the solid carbon can comprise graphite as measured by a degree of graphitization. The carbon as produced may have a degree of graphitization of at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 89%, or at least about 90%, as measured using powder X-ray dirfraction (Bragg-Brentano configuration) to measure the 20 value of the

[0002] peak to calculate the

[0002] plane spacing, d002. Graphitization may be improved using heat treatments before or after one or more option processes to reduce the amount of catalyst present such as an acid wash. When a heat treatment is used to increase the degree of graphitization, the carbon can be heated at between about 1,000 C to about 3,500 C, or between about 2,000 C to about 3,000 C for a time period between about 1 minute to about 3 hours, or between about 30 minutes an about 2 hours. The heat treatment can be used to improve the d-spacing of the

[0002] plane, corresponding to an increase in the fraction of ordered layers in the carbon. In some aspects, the fraction of ordered planes in the carbon can be at least about 0.4, at least about 0.5, at least about 0.55, at least about 0.6, at least about 0.65, at least about 0.66, at least about 0.67, or at least about 0.68.

[0059] The composition of the solid carbon can also be used to advantageously allow for the separation of the carbon from the gaseous products. When a magnetic catalyst such as iron is used as the catalyst, a magnetic field can be used to help separate the carbon from the gaseous products. As noted above, the resulting carbon can be hydrophilic. While not intending to be limited by theory, it is anticipated that the presence of the catalyst can render the carbon product hydrophilic when pure carbon is hydrophobic. The hydrophilic nature of the carbon can allow for an aqueous fluid to be used to separate the carbon from the gaseous products. For example, a direct contact cooler can be used to contact the gaseous product stream and remove any solid carbon particles in the gaseous product stream. Due to the hydrophilic nature of the carbon, the carbon can be captured in the aqueous phase and separated from the gaseous products.

[0060] In some aspects, the individual carbon particles may have a density of greater than 1 g / cm3 due to the presence of the catalyst. When used with a separator using an aqueous fluid, the solid carbon may sink within the fluid. This can allow for an aqueous fluid to be used to separate the solid carbon from a gas phase and then use a settling chamber or other fluid separator (e.g., hydrocyclone, etc.) to separate the solid from the aqueous phase. Thus, a method of separating carbon from gas phase products can include contacting the carbon with an aqueous fluid, and separating the solid carbon from bottom of the aqueous fluid to recover a solid carbon product.EXAMPLES

[0061] The disclosure having been generally described, the following examples are given as particular embodiments of the disclosure and to demonstrate the practice and advantages thereof. It is understood that the examples are given by way of illustration and are not intended to limit the specification or the claims in any manner.EXAMPLE 1Heat of Combustion

[0062] In this example, a sample of solid carbon obtained from a carbon formation reactor was acid washed to remove a portion of the iron catalytic material. The resulting acid washed sample had 1.54 wt.% iron and a 63.9: 1 carbon to iron weight ratio. The sample was then tested to determine the heat of combustion according to the standard testing method ASTM D5865.

[0063] The measured heat of combustion was 13,987 BTU / lb of solid carbon. This is equivalent to approximately 395.4 kJ / mol, which is slightly higher than the expected heat of combustion of 393.56 kJ / mol for pure carbon.

[0064] The experimental enthalpy of formation of the carbon in the sample was 1.835 kJ / mol. Based on literature values, a sample containing 98.5%C / 1.5% Fe with pure graphite carbon (enthalpy of formation of 0) would have a heat of combustion of 393.56 kJ / mol. The difference between the experimental value and literature value was -0.46%. Given the difference (0.46%) is within experimental error (+ / -!% of expected value), the results demonstrate that the carbon tested is graphitic and / or highly graphitic in nature. Some other species can account for the measured heat of formation.EXAMPLE 2Heat of Combustion

[0065] In this example, a sample of solid carbon w eighing 346.6 g and having a composition of 80. 1 wt.% carbon with the balance being the iron catalyst (with a 4.03: 1 carbon to iron weightratio) was tested. The sample was then tested to determine the heat of combustion according to the standard testing method ASTM D5865. The heat of combustion of the sample was measured at 9,934 BTU / lb, which is equivalent to 329.19 kJ / mol.

[0066] The reported heat of combustion for the sample has the measured value potentially due to the sample being high in iron species that may have not fully oxidized. This demonstrates the heat of combustion for the solid carbon having a higher catalyst loading.EXAMPLE 3Thermal Properties

[0067] In this example, a sample of solid carbon having a composition of 89.65 wt.% carbon with the balance being the iron catalyst (with a 8.66: 1 carbon to iron weight ratio) was tested to measure the thermal diffusivity (using ASTM E1461), thermal conductivity, and the heat capacity (using ASTM El 269) of the sample. The thermal conductivity was calculated from the measured thermal diffusivity and heat capacity using the following equation:D = / (cpp where D is the thermal diffusivity, is the thermal conductivity, cpis the heat capacity, and p is the density.

[0068] The results are shown in FIGS. 3-5. As shown in FIG. 3, the thermal diffusivity varies based on temperature and ranged from about 0.55 to about 0.34 mm2 / s over a temperature from about 25 °C to about 800 °C. The thermal diffusivity values can vary with the packing density, and the testing was performed at a packing density of 0.625 g / cm3. As shown in FIG. 4, the thermal conductivity varied from about 0.31 to about 0.55 W / mol-K over a temperature from about 25 °C to about 800 °C. As shown in FIG. 5, the heat capacity varied from about 18 to about 30 J / mol-K over a temperature from about 250 °C to about 750 °C.

[0069] The results were used to establish relationships for the thermal properties as follows: Cp=0.0228[C+273.15] + 5.156 [J / molK] a=((C2)*7xl O-7) - (0.0008C) + (0.548) [mm2 / s]X=((C2)*6xl O'7) - 0.0002C + 0.3218 [W / molK]

[0070] These formulas allow for the calculation of the thermal properties of the carbon material at temperatures ranging from ~25 °C up to the reactor operating temperature of -720 °C.EXAMPLE 4Electrical Properties

[0071] In this example, a sample of solid carbon having an iron content of 6.46 wt.% w ith the balance being carbon (with a 14.5: 1 carbon to iron weight ratio) was tested to measure the electrical properties of the sample. In this test process, the carbon powder (18-21 cm3) was placed in an Electro-Tech Systems liquid / powder cell and vibrated to achieve initial packing. The upper electrode was attached to a mechanical load-frame. The resistivity' was measured using a TEGAM precision ohmmeter at different compressive loads, corresponding to a range of powder bulk densities.

[0072] The results are shown in FIGS. 6-9. As shown in the figures, the resistivity and conductance at different densities w ere found to be:@0.58 g / cm3: Resistivity= 65.5 (+ / -11.8) Q*cm | Conductance = ~ 0.5 Siemens (66.9 Q*cm / 0.345 S avg observed respectively)@0.92 g / cm3: Resistivity= 10.55 (+ / -3.7) Q*cm | Conductance = ~ 4.5 Siemens (7.18 *cm / 4.86 avg S observed respectively)

[0073] The results were used to establish relationships for the thermal properties as follows: Resistivity’: (Q*cm) = 55*[(lxl0-9)A(Density-0.58)]+10.5Conductance: (S) =11.87(Density) - 6.39 (uncertainty of slope=1.18 / intercepts).9) EXAMPLE 5Graphitization Properties

[0074] In this example, the degree of graphitization of the solid carbon was investigated. A sample of acid washed solid carbon having an iron content of 1.54 wt.% and a carbon to iron ratio of 63.9: 1 was tested. The carbon was heat treated at 2,500 C for 30 minutes prior to testing. X-ray diffraction scans of the heat treated powder were used to determine the degree of graphitization. More specifically, powder X-ray diffraction (Bragg-Brentano configuration) was performed on a sample of material. The 20 value of the

[0002] peak was used to calculate the

[0002] plane spacing, d002. The degree of graphitization p was calculated from the following equation: doo2 = 3.44 - 0.0861(1 -@).

[0075] The results are shown in FIGS. 10 and 11. The results show that the carbon sample had a 94% prevalence of (002) structure within the graphite powder. The measured d-spacing of the (002) C was 3.378 A prior to heat treatment and 3.374 A after the heat treatment. The fraction of ordered layers (1-p) w as found to be 0.461 for the standard sample and .506 for the post heat treated sample. This indicates an increase in the degree of graphitization. Included in FIG. 10 are other samples of graphitized carbon to help indicate degree of graphitizability of the carbon samples tested in this example.EXAMPLE 6Physical Properties

[0076] In this example, the physical properties of multiple samples were investigated. The properties tested included the particle size distribution, the crystallinity, the surface area, the contact angle (e.g., wettability), the angle of repose, and compaction of the samples. Two samples were tested. The first was a labeled AW-073 and included a carbon to iron weight ratio of 63.8: 1 (-1.56 wt.% iron). The second sample was labeled VT-073 and included a carbon to iron weight ratio of 10.6: 1 (-9.43 wt.% iron). For the tests, ASTM D3849 was used to measure the particle size distribution and the particle morphology' and crystallinity, and the surface area was measured by ASTM D6556, where each test was based on the current version as of the date of the present filing. Iodine absorption testing was conducted according to ASTM D1510, and the plastic properties of the carbon were performed using ASTM D2639.

[0077] The results of the physical property' testing are shown in FIGS. 12-16. As shown in FIG. 12, the particle size of both samples generally varies between about 2 pm and about 210 pm, with the middle 60% of particles (e.g., from about 20% passing to about 80% passing) having a size distribution from about 4 pm to about 45 pm. For the majority' of the particles, the increased w eight percentage of the catalyst results in larger particle sizes.

[0078] As shown in FIG. 13, the surface area of AW-073 was about 32.46 m2 / g with a non- measurable micropore volume. The surface area of VT-073 was about 39.78 m2 / g with a micropore volume of about 0.0013 cm3 / g. For comparison, reported values of activated carbon surface area is on the order of 1000 m2 / g.

[0079] As shown in FIG. 14, the X-ray diffraction analysis shows the crystallinity of AW-073 of about 49.03% while the crystallinity of VT-073 is lower at about 32.74%.

[0080] The contact angle of the carbon was also measured. The contact angle was measured by the thin layer wicking method in which a sample of the powder is suspended in distilled water and transferred onto a glass slide. The powder sediments on the glass slide and adheres upon evaporation of the water. The glass slide was then immersed vertically in distilled water. The change in height of the water in contact with the thin film was measured with a video camera. The contact angle 0 was calculated from the Washbum equation: where r isthe capillary' radius, h is the liquid height, y is the surface energy, p is the viscosity', and t is the time of the liquid rise.

[0081] As shown in FIG. 15, the solid carbon samples have a contact angle between 57-66 degrees. Specifically, the contact angle shows that the contact angle of AW-073 is about 65.5degrees, and the contact angle of VT-073 is about 57.0 degrees. A contact angle of less than 90 degrees is generally considered hydrophilic. The precise contact angle will affect the performance of the material in different applications and the binary characterization as hydrophobic or hydrophilic is often not of much significance for materials with a contact angle near 90 degrees. Without intending to be limited by theory, it is anticipate that an increased amount of catalyst in the solid carbon can reduce the contact angle of the carbon, though the presence of even minor amounts of the catalyst appear to render the solid carbon hydrophilic.

[0082] FIG. 16 illustrates the results of the compaction test. The test uses a Harvard miniature test that is related to the industry standard compaction test according to ASTM D4647 that uses smaller volumes of material. The test apparatus simulates kneading compaction using a spring loaded tamper. The results show a dry unit weight of around 52-57 lbs / ft3for water contents ranging from about 47 to about 70 wt.% for VT-073, and a weight of around 46-53 lbs / ft3for water contents ranging from about 37-68 wt.% for AW-073.

[0083] FIG. 17 illustrates the results of the angle of repose test. The test uses the fixed funnel method whereby the powder is poured through a funnel and placed onto a platform, forming a cone. The height and radius of the heap were measured and the angle of repose was calculated. The angle of repose was measured for samples produced with different C / Fe mass ratios and collected at different locations in the process. The results show an angle of repose of 28-34 degrees for solids collected in the solids overflow and 40-42 degrees for solids collected in a gas filter trap. Across all samples the angle of repose increased as the C / Fe mass ratio increased.

[0084] Having described various systems, methods, and compositions, various aspects of the present disclosure can include, but are not limited to:

[0085] In a first aspect, a material comprises: solid carbon; and a metal selected from the group consisting of a Group VI element, a Group VII element, a Group VIII element, a Group IX element, and a Group X element, wherein the metal is encompassed by the solid carbon.

[0086] A second aspect can include the material of the first aspect, wherein the metal comprises iron, nickel, molybdenum, platinum, chromium, cobalt, tungsten, or any combination thereof.

[0087] A third aspect can include the material of the first aspect, wherein the metal comprises iron.

[0088] A fourth aspect can include the material of any one of the first to third aspects, wherein a mass ratio of the solid carbon to the metal is in the range of about 500: 1 to about 1 : 1 , in a range of about 100:1 to about 3: 1, or in a range of about 75: 1 to about 5: 1.

[0089] A fifth aspect can include the material of any one of the first to fourth aspects, wherein the solid carbon comprises at least about 50 wt.% of the material.

[0090] A sixth aspect can include the material of any one of the first to fifth aspects, wherein the material has a heat of combustion between about 400 kJ / mol and about 300 kJ / mol, or between about 398 kJ / mol and about 310 kJ / mol, or between about 396 kJ / mol and about 330 kJ / mol.

[0091] A seventh aspect can include the material of any one of the first to sixth aspects, wherein the material has a thermal diffusivity in a range from about 0.6 to about 0.30 mm2 / s.

[0092] An eighth aspect can include the material of any one of the first to seventh aspects, wherein the material has a thermal conductivity from about 0.30 to about 0.60 W / mol-K.

[0093] A ninth aspect can include the material of any one of the first to eighth aspects, wherein the material has a heat capacity from about 15 to about 35 J / mol-K, or between about 18 to about 30 J / mol-K.

[0094] A tenth aspect can include the material of any one of the first to ninth aspects, wherein the material has an electrical resistivity' from about 7 to about 80 *cm, from about 9 to about 70 Q*cm, or from about 10 to about 66 *cm.

[0095] An eleventh aspect can include the material of any one of the first to tenth aspects, wherein the material has an electrical conductance from about 0.2 Siemens (S) to about 5.5 S, or from about 0.3 S to about 4.9 S, or from about 0.5 S to about 4.5 S

[0096] A tw elfth aspect can include the material of any one of the first to eleventh aspects, wherein the material has a bulk density from about 0.55 g / cm3to about .95 g / cm3, or between about 0.58 g / cm3to about 0.92 g / cm3.

[0097] A thirteenth aspect can include the material of any one of the first to twelfth aspects, wherein the material has a particle size betw een about 2 pm and about 210 pm, or between about 3 pm to about 150 pm.

[0098] A fourteenth aspect can include the material of any one of the first to thirteenth aspects, wherein a surface area of the material is from about 30 m2 / g to about 40 m2 / g.

[0099] A fifteenth aspect can include the material of any one of the first to fourteenth aspects, wherein a crystallinity of the solid carbon is between about 30% to about 50%.

[0100] A sixteenth aspect can include the material of any one of the first to fifteenth aspects, wherein the material is hydrophilic.

[0101] A seventeenth aspect can include the material of any one of the first to sixteenth aspects, wherein a contact angle of the material is less than 80 degrees.

[0102] An eighteenth aspect can include the material of any one of the first to seventeenth aspects, wherein an angle of repose of the material is between 20-50 degrees.

[0103] In a nineteenth aspect, a method of forming a solid carbon comprises: contacting a reaction stream comprising a carbon oxide, and a hydrocarbon with a catalyst; forming solid carbon and gaseous products in response to the contacting, wherein the solid carbon comprises a portion of the catalyst; and separating the solid carbon from the gaseous products to form a solid carbon product.

[0104] A twentieth aspect can include the method of the nineteenth aspect, wherein the carbon oxide comprises carbon monoxide.

[0105] A twenty first aspect can include the method of the nineteenth or twentieth aspect, wherein the carbon oxide comprises carbon dioxide.

[0106] A twenty second aspect can include the method of any one of the nineteenth to twenty first aspects, wherein the catalyst comprises a Group VI element, a Group VII element, a Group VIII element, a Group IX element, or a Group X element, wherein the catalyst is encompassed by the solid carbon in the solid carbon product.

[0107] A tw enty third aspect can include the method of any one of the nineteenth to twenty- second aspects, wherein the catalyst comprises iron, nickel, molybdenum, platinum, chromium, cobalt, tungsten, or any combination thereof.

[0108] A twenty fourth aspect can include the method of any one of the nineteenth to twenty third aspects, wherein the catalyst comprises iron.

[0109] A t enty fifth aspect can include the method of any one of the nineteenth to twenty fourth aspects, wherein a mass ratio of the solid carbon to the metal is in the range of about 500: 1 to about 1 : 1 , in a range of about 100: 1 to about 3: 1 , or in a range of about 75: 1 to about 5: 1.

[0110] A twenty sixth aspect can include the method of any one of the nineteenth to twenty fifth aspects, wherein the solid carbon comprises at least about 50 wt.% of the solid carbon product.

[0111] A twenty seventh aspect can include the method of any one of the nineteenth to twenty sixth aspects, wherein the solid carbon product has a heat of combustion between about 400 kJ / mol and about 300 kJ / mol, or between about 398 kJ / mol and about 310 kJ / mol, or between about 396 kJ / mol and about 330 kJ / mol.

[0112] A twenty eighth aspect can include the method of any one of the nineteenth to twenty seventh aspects, wherein the solid carbon product has a thermal diffusivity in a range from about 0.6 to about 0.30 mm2 / s.

[0113] A tw enty ninth aspect can include the method of any one of the nineteenth to twenty eighth aspects, wherein the solid carbon product has a thermal conductivity from about 0.30 to about 0.60 W / mol-K.

[0114] A thirtieth aspect can include the method of any one of the nineteenth to twenty ninth aspects, wherein the solid carbon product has a heat capacity from about 15 to about 35 J / mol- K, or between about 18 to about 30 J / mol-K.

[0115] A thirty first aspect can include the method of any one of the nineteenth to thirtieth aspects, wherein the solid carbon product has an electrical resistivity7from about 7 to about 80 *cm, from about 9 to about 70 Q*cm, or from about 10 to about 66 Q*cm.

[0116] A thirty second aspect can include the method of any one of the nineteenth to thirty first aspects, wherein the solid carbon product has an electrical conductance from about 0.2 Siemens (S) to about 5.5 S, or from about 0.3 S to about 4.9 S, or from about 0.5 S to about 4.5 S

[0117] A thirty third aspect can include the method of any one of the nineteenth to thirty second aspects, wherein the solid carbon product has a bulk density from about 0.55 g / cm3to about .95 g / cm3, or between about 0.58 g / cm3to about 0.92 g / cm3.

[0118] A thirty fourth aspect can include the method of any one of the nineteenth to thirty7third aspects, wherein the solid carbon product has a particle size between about 2 pm and about 210 pm, or between about 3 pm to about 150 pm.

[0119] A thirty fifth aspect can include the method of any one of the nineteenth to thirty fourth aspects, wherein a surface area of the solid carbon product is from about 30 m2 / g to about 40 m2 / g.

[0120] A thirty sixth aspect can include the method of any one of the nineteenth to thirty7fifth aspects, wherein a crystallinity of the solid carbon is between about 30% to about 50%.

[0121] A thirty7seventh aspect can include the method of any one of the nineteenth to thirty sixth aspects, wherein the solid carbon product is hydrophilic.

[0122] A thirty eighth aspect can include the method of any one of the nineteenth to thirty seventh aspects, wherein a contact angle of the solid carbon product is less than 80 degrees.

[0123] A thirty ninth aspect can include the method of any one of the nineteenth to thirty eighth aspects, wherein an angle of repose of the solid carbon product is between 20-50 degrees.

[0124] In a fortieth aspect, a method of separating carbon from a gas stream comprises: contacting a gas stream comprising solid carbon particles with an aqueous fluid; wetting the solid carbon particles with the aqueous fluid; separating the solid carbon particles from the aqueous fluid; and recovering the solid carbon particles as a product stream.

[0125] A forty first aspect can include the method of the fortieth aspect, wherein the solid carbon particles are hydrophilic.

[0126] A forty second aspect can include the method of the fortieth or forty first aspect, wherein the solid carbon particles have a density greater than that of the aqueous fluid.

[0127] It is to be further understood that the present description is not limited to the particular methodology, compounds, materials, manufacturing techniques, uses, and applications, described herein, as these may vary. It is also to be understood that the terminology7used herein is used for the purpose of describing particular embodiments only, and is not intended to limit the scope of the present systems and methods. It must be noted that as used herein and in the appended claims (in this application, or any derived applications thereof), the singular forms "a," "an," and "the" include the plural reference unless the context clearly dictates otherwise. Thus, for example, a reference to "an element" is a reference to one or more elements and includes equivalents thereof known to those skilled in the art. All conjunctions used are to be understood in the most inclusive sense possible. Thus, the word "or" should be understood as having the definition of a logical "or" rather than that of a logical "exclusive or" unless the context clearly necessitates otherwise. Structures described herein are to be understood also to refer to functional equivalents of such structures. Language that may be construed to express approximation should be so understood unless the context clearly dictates otherwise.

[0128] Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary7skill in the art to w hich this description belongs. Preferred methods, techniques, devices, and materials are described, although any methods, techniques, devices, or materials similar or equivalent to those described herein may be used in the practice or testing of the present systems and methods. Structures described herein are to be understood also to refer to functional equivalents of such structures. The present systems and methods will now be described in detail with reference to embodiments thereof as illustrated in the accompanying drawings.

[0129] From reading the present disclosure, other variations and modifications will be apparent to persons skilled in the art. Such variations and modifications may involve equivalent and other features which are already known in the art, and which may be used instead of or in addition to features already described herein.

[0130] Although Claims may be formulated in this Application or of any further Application derived therefrom, to particular combinations of features, it should be understood that the scope of the disclosure also includes any novel feature or any novel combination of features disclosed herein either explicitly or implicitly or any generalization thereof, whether or not it relates to the same systems or methods as presently claimed in any Claim and whether or not it mitigates any or all of the same technical problems as do the present systems and methods.

[0131] Features which are described in the context of separate embodiments may also be provided in combination in a single embodiment. Conversely, various features which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination. The Applicants hereby give notice that new claims may be formulated to such features and / or combinations of such features during the prosecution of the present Application or of any further Application derived therefrom.

Claims

CLAIMS1. A material comprising: solid carbon; and a metal selected from the group consisting of a Group VI element, a Group VII element, a Group VIII element, a Group IX element, and a Group X element, wherein the metal is encompassed by the solid carbon.

2. The material of claim 1, wherein the metal comprises iron, nickel, molybdenum, platinum, chromium, cobalt, tungsten, or any combination thereof.

3. The material of claim 1, wherein the metal comprises iron.

4. The material of claim 1, wherein a mass ratio of the solid carbon to the metal is in the range of about 500: 1 to about 1 : 1.

5. The material of claim 1, wherein the solid carbon comprises at least about 50 wt.% of the material.

6. The material of claim 1, wherein the material has a heat of combustion between about 400 kJ / mol and about 300 kJ / mol.

7. The material of claim 1, wherein the material has a thermal diffusivity in a range from about 0.6 to about 0.30 mm2 / s.

8. The material of claim 1, wherein the material has a thermal conductivity7from about 0.30 to about 0.60 W / mol-K.

9. The material of claim 1, wherein the material has a heat capacity from about 15 to about 35 J / mol-K.

10. The material of claim 1, wherein the material has an electrical resistivity7from about 7 to about 80 Q*cm.

11. The material of claim 1, wherein the material has an electrical conductance from about 0.2 Siemens (S) to about 5.5 S.

12. The material of claim 1, wherein the material has a bulk density7from about 0.55 g / cm3to about .95 g / cm3.

13. The material of claim 1, wherein the material has a particle size between about 2 pm and about 210 pm.

14. The material of claim 1, wherein a surface area of the material is from about 30 m2 / g to about 40 m2 / g.

15. The material of claim 1, wherein a crystallinity of the solid carbon is between about 30% to about 50%.

16. The material of claim 1, wherein the material is hydrophilic.

17. The material of claim 1, wherein a contact angle of the material is less than 80 degrees.

18. The material of claim 1, wherein an angle of repose of the material is between 20-50 degrees.

19. A method of forming a solid carbon product, the method comprising: contacting a reaction stream comprising, a carbon oxide, and a hydrocarbon with a catalyst; forming solid carbon and gaseous products in response to the contacting, wherein the solid carbon comprises a portion of the catalyst; and separating the solid carbon from the gaseous products to form a solid carbon product.

20. The method of claim 19, wherein the carbon oxide comprises carbon monoxide.

21. The method of claim 19, wherein the carbon oxide comprises carbon dioxide.

22. The method of claim 19, wherein the catalyst comprises a Group VI element, a GroupVII element, a Group VIII element, a Group IX element, or a Group X element, wherein the catalyst is encompassed by the solid carbon in the solid carbon product.

23. The method of claim 19, wherein the catalyst comprises iron, nickel, molybdenum, platinum, chromium, cobalt, tungsten, or any combination thereof.

24. The method of claim 19, wherein the catalyst comprises iron.

25. The method of claim 19. wherein a mass ratio of the solid carbon to the metal is in the range of about 500: 1 to about 1 : 1.

26. The method of claim 19, wherein the solid carbon comprises at least about 50 wt.% of the solid carbon product.

27. The method of claim 19, wherein the solid carbon product has a heat of combustion between about 400 kJ / mol and about 300 kJ / mol.

28. The method of claim 19, wherein the solid carbon product has a thermal diffusivity in a range from about 0.6 to about 0.30 mm2 / s.

29. The method of claim 19, wherein the solid carbon product has a thermal conductivity from about 0.30 to about 0.60 W / mol-K.

30. The method of claim 19, wherein the solid carbon product has a heat capacity from about 15 to about 35 J / mol-K.

31. The method of claim 19, wherein the solid carbon product has an electrical resistivity from about 7 to about 80 Q*cm.

32. The method of claim 19, wherein the solid carbon product has an electrical conductance from about 0.2 Siemens (S) to about 5.5 S.

33. The method of claim 19, wherein the solid carbon product has a bulk density from about 0.55 g / cm3to about .95 g / cm3.

34. The method of claim 19, wherein the solid carbon product has a particle size between about 2 pm and about 210 pm.

35. The method of claim 19, wherein a surface area of the solid carbon product is from about 30 m2 / g to about 40 m2 / g.

36. The method of claim 19, wherein a cry stallinity of the solid carbon product is between about 30% to about 50%.

37. The method of claim 19, wherein the solid carbon product is hydrophilic.

38. The method of claim 19, wherein a contact angle of the solid carbon product is less than 80 degrees.

39. The method of claim 19, wherein an angle of repose of the solid carbon product is between 20-50 degrees.

40. The method of claim 19, wherein the solid carbon product has a degree of graphitization of at least 80%.

41. A method of separating carbon from a gas stream, the method comprising: contacting a gas stream comprising solid carbon particles with an aqueous fluid; wetting the solid carbon particles with the aqueous fluid; separating the solid carbon particles from the aqueous fluid; and recovering the solid carbon particles as a product stream.

42. The method of claim 41, wherein the solid carbon particles are hydrophilic.

43. The method of claim 41. wherein the solid carbon particles have a density greater than that of the aqueous fluid.

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