Recycled raw materials for producing carbon and hydrogen

Abstract

The present disclosure provides a system and method for producing carbon particles. The system of the present disclosure may include a reactor for pyrolyzing a hydrocarbon feedstock into carbon particles. The method of the present disclosure may include contacting a non-hydrogen gas with a hydrocarbon feedstock in the presence of a plasma within a reactor to produce carbon particles and an exhaust gas. The exhaust gas may include hydrogen and the non-hydrogen gas. The method may further include separating at least a portion of the exhaust gas into hydrogen and the non-hydrogen gas to obtain a separated gas containing the non-hydrogen gas. The separated gas containing the non-hydrogen gas can be recycled or otherwise returned to the reactor to produce additional carbon particles and exhaust gas.

Description

Technical Field

[0001] Cross-reference This application claims the benefit of U.S. Provisional Application No. 63 / 347,865, filed on June 1, 2022, which is hereby incorporated by reference in its entirety.

Background Art

[0002] Background Carbonaceous materials or hydrogen can be produced by various chemical processes. The performance, energy supply, and environmental performance associated with such chemical processes have evolved over time.

Summary of the Invention

Means for Solving the Problems

[0003] Abstract The present disclosure provides a method and a system for increasing the efficiency of a conversion reaction in a reactor. By the method and system described herein, a feedstock can be converted into carbon particles at a lower temperature than other methods and systems, increasing the usage efficiency of materials and reducing wear of the apparatus. Such improvements can enable scale-up from bench scale to industrial scale to be efficient with respect to energy and material usage and cost.

[0004] In one aspect, the present disclosure provides a method for producing carbon particles, comprising: (a) contacting a non-hydrogen gas with a hydrocarbon raw material in the presence of a plasma in a reactor to thereby obtain (i) carbon particles and (ii) an exhaust gas containing hydrogen and the non-hydrogen gas; (b) separating at least a part of hydrogen from the non-hydrogen gas of the exhaust gas to thereby obtain a separated gas containing the non-hydrogen gas; (c) providing the separated gas containing the non-hydrogen gas or a derivative thereof to the reactor; and (d) contacting the separated gas containing the non-hydrogen gas or a derivative thereof with a further hydrocarbon raw material in the presence of a plasma to thereby obtain (iii) further carbon particles and (iv) a further exhaust gas containing hydrogen and the non-hydrogen gas.

[0005] In some embodiments, the non-hydrogen gas comprises one or more gases selected from the group consisting of nitrogen, helium, neon, krypton, argon, carbon monoxide, and carbon dioxide. In some embodiments, the separated gas or a derivative thereof contains about 50 mole percent (mol%) or less hydrogen. In some embodiments, the separated gas or a derivative thereof contains about 25 mol% or less hydrogen. In some embodiments, the separated gas or a derivative thereof contains about 10 mol% or less hydrogen. In some embodiments, the method further comprises, in (a), providing to the reactor a gas mixture containing the non-hydrogen gas and hydrogen. In some embodiments, the gas mixture has an average molecular weight of about 1 kg / kmol to 90 kg / kmol. In some embodiments, in (a), the ratio of the non-hydrogen gas to hydrogen is at least 2 to 1. In some embodiments, the ratio is at least 10 to 1. In some embodiments, the method further comprises, in (c), providing to the reactor a gas mixture containing the separated gas or a derivative thereof and hydrogen. In some embodiments, in (d), the ratio of the non-hydrogen gas to hydrogen is at least 2 to 1. In some embodiments, the ratio is at least 10 to 1. In some embodiments, no hydrogen is provided to the reactor during or after (c).

[0006] In some embodiments, the carbon particles or additional carbon particles are carbon black. In some embodiments, the method further comprises contacting, in (a), a non-hydrogen gas and a hydrocarbon feedstock at a temperature of about 1900 °C or less. In some embodiments, the temperature is about 1800 °C or less. In some embodiments, the method further comprises contacting, in (d), a separation gas and an additional hydrocarbon feedstock at a temperature of about 1900 °C or less. In some embodiments, the temperature is about 1800 °C or less. In some embodiments, the carbon particles or additional carbon particles have a specific surface area of at least about 40 square meters per gram (m 2 / g). In some embodiments, the carbon particles or additional carbon particles have a specific surface area of about 40 m 2 / g to 200 m 2 / g. In some embodiments, the carbon particles or additional carbon particles have a nitrogen surface area (N2SA) of at least about 40 m 2 / g. In some embodiments, the carbon particles or additional carbon particles have a dibutyl phthalate (DBP) absorption of at least about 100 milliliters per 100 grams of carbon particles (mL / 100g). In some embodiments, the carbon particles are produced in the presence of an additive that inhibits aggregation of the carbon particles. In some embodiments, the additive comprises an alkali metal salt. In some embodiments, the alkali metal salt comprises potassium. In some embodiments, the carbon particles are produced in the absence of an additive that inhibits particle aggregation. In some embodiments, the carbon particles are produced in the absence of an alkali metal salt. In some embodiments, the carbon particles are produced in the absence of potassium.

[0007] In some embodiments, in (a), at least about 80% of the hydrocarbon feedstock is converted to carbon particles. In some embodiments, in (a), at least about 90% of the hydrocarbon feedstock is converted to carbon particles. In some embodiments, in (a), at least about 95% of the hydrocarbon feedstock is converted to carbon particles. In some embodiments, in (d), the conversion rate of additional hydrocarbon feedstock to additional carbon particles is at least about 80%. In some embodiments, in (d), the conversion rate of additional hydrocarbon feedstock to additional carbon particles is at least about 90%. In some embodiments, in (d), the conversion rate of additional hydrocarbon feedstock to additional carbon particles is at least about 95%.

[0008] In some embodiments, the method further includes generating plasma by utilizing electrodes. In some embodiments, throughout (a)-(d), the electrodes are consumed at a rate of about 0.6 kilograms of carbon per megawatt-hour (kg carbon / MW-hr) or less. In some embodiments, the reactor includes one or more graphite components, and the one or more graphite components have a wear rate of about 0.6 kg carbon / MW-hr or less. In some embodiments, the method further includes, in (a) or (d), producing an amount of reactor fouling that is about 4 kilograms or less of carbon fouling per 100 kilograms of carbon injected. In some embodiments, the hydrocarbon feedstock includes methane. In some embodiments, the method further includes providing an external gas to the reactor prior to (d), and the external gas includes additional non-hydrogen gas. In some embodiments, the ratio of non-hydrogen gas to hydrogen is at least about 4 to 1. In some embodiments, the ratio is at least about 10 to 1. In some embodiments, (b) includes separating at least a portion of the hydrogen from the non-hydrogen gas using one or more of pressure swing adsorption, membrane separation, cryogenic separation, absorption column, stripping column, gas compressor, and external supply. In some embodiments, the method further includes separating the carbon particles from the non-hydrogen gas after (a).

[0009] In some embodiments, the method further includes providing an energy input to generate a plasma, and the energy input per kilogram of hydrogen produced is at least about 15% less compared to another gas mixture containing about 80 mol% or more hydrogen in a gas mixture containing at least 50 mol% non-hydrogen gas. In some embodiments, the total energy input to obtain carbon particles and hydrogen is within about 10% compared to another gas mixture containing about 80 mol% or more hydrogen in a gas mixture containing at least 50 mol% non-hydrogen gas. In some embodiments, about 90% or more of the non-hydrogen gas provided to the reactor is returned to the reactor as a separated gas. In some embodiments, about 95% or more of the non-hydrogen gas provided to the reactor is returned to the reactor as a separated gas. In some embodiments, the method further includes providing a non-hydrogen gas to the reactor for a time sufficient for the reactor to reach a thermal steady state in a state where plasma is present and hydrocarbon feedstock is absent, prior to (a).

[0010] In some embodiments, the method further includes providing to the reactor a gas mixture containing at least 50 mol% non-hydrogen gas and hydrogen in (a) or (d) to produce carbon particles or additional carbon particles. In some embodiments, the carbon particles or additional carbon particles have a DBP structure of at least about 100 mL / 100 g. In some embodiments, the carbon particles or additional carbon particles are natural carbon particles, and the natural carbon particles have a DBP structure that is about 30% or more greater than other natural carbon particles produced in a gas mixture containing 80 mol% or more hydrogen.

[0011] In some embodiments, the method further includes providing a first gas to a reactor together with a hydrocarbon feedstock to initiate a reaction to produce carbon particles and hydrogen. In some embodiments, the first gas contains about 80% or more hydrogen. In some embodiments, the method further includes using a quench gas to cool the carbon particles, additional carbon particles, emissions, additional emissions, or any combination thereof. In some embodiments, the quench gas is produced from an exhaust gas and the quench gas contains from about 0.1 mol% to about 4 mol% hydrocarbon.

[0012] Further aspects and advantages of the present disclosure will become readily apparent to those skilled in the art from the following detailed description, which illustrates and describes only exemplary embodiments of the present disclosure. As will be understood, the present disclosure is capable of other and different embodiments and some of the details thereof can be modified in various obvious respects all without departing from the present disclosure. Accordingly, the drawings and description are to be regarded as illustrative in nature and not as restrictive. Incorporation by reference

[0013] All publications, patents, and patent applications mentioned herein are hereby incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference. If a publication and a patent or patent application incorporated by reference conflict with the disclosure contained herein, the present specification is intended to supersede and / or take precedence over any such conflicting material.

[0014] The novel features of the invention are set forth with particularity in the appended claims. The features and advantages of the invention will be better understood from the following detailed description, which describes exemplary embodiments in which the principles of the invention are utilized, and from the accompanying drawings (also referred to herein as "figures" and "FIGs."). BRIEF DESCRIPTION OF THE DRAWINGS

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DETAILED DESCRIPTION OF THE INVENTION

[0026] Detailed Description Although various embodiments of the present invention are shown and described in this specification, it will be apparent to those skilled in the art that such embodiments are provided for illustrative purposes only. Those skilled in the art can come up with numerous variations, modifications, and substitutions without departing from the present invention. It should be understood that various alternatives of the embodiments of the present invention described in this specification can be used.

[0027] As used herein, the term "carbon particles" can refer to particles containing carbon. Examples of carbon particles include, but are not limited to, carbon black, nanotubes, carbon nanostructures, graphene, coke, needle coke, graphite, macrocyclic polycyclic aromatic hydrocarbons, activated carbon, etc., or any combination thereof. Carbon black includes all forms of carbon black, including, but not limited to, furnace black, plasma black, thermal black, acetylene black, or any combination thereof. The carbon particles can be classified into grades. The carbon particles of the present disclosure can be of any grade.

[0028] As used herein, the term "carbon black" can refer to, for example, nanostructured materials having a high carbon content of more than 90% by elemental composition. Carbon black may be in the form of fine quasi-spherical particles (e.g., primary particles) and can be connected or aggregated together by covalent linkages to form chain-like aggregates or other structures. The aggregates can form agglomerates by weak bonds (e.g., van der Waals forces) that can be broken under mechanical stress. The average diameter of the primary particles can vary between several tens of nanometers and several hundreds of nanometers depending on the production process.

[0029] As used herein, the term "structure" can refer to the organization of primary particles within an aggregate. A high structure can correspond to an organization containing a large number of highly branched and extensively intertwined particles. A low structure can correspond to an organization consisting of isolated particles or aggregates (agglomerates of a small number of primary particles) having a small number of branches. This structure can be measured using dibutyl phthalate absorption.

[0030] When the terms "at least", "greater than", or "or more" are before or after the first numerical value of a series of two or more numerical values, the terms "at least", "greater than", or "or more" always apply to each numerical value of that series of numerical values. For example, 1, 2, or 3 or more is equivalent to 1 or more, 2 or more, or 3 or more.

[0031] When the terms "below", "less than", or "or less" are after the first numerical value of a series of two or more numerical values, the terms "below", "less than", or "or less" always apply to each numerical value of that series of numerical values. For example, 3, 2, or 1 or less is equivalent to 3 or less, 2 or less, or 1 or less.

[0032] In certain embodiments of the present specification, numerical ranges are contemplated. When a range exists, the range includes the endpoints of the range. In addition, all sub-ranges and values within the range exist as if they were explicitly written out. The term "about" or "approximately" may mean within an acceptable error range for a particular value, which is determined in part by how the value is measured or determined, e.g., the limitations of the measurement system. For example, "about" may mean within 1 or greater than 1 standard deviation according to the practice in the art. Alternatively, "about" may mean within a range of up to 20%, up to 10%, up to 5%, or up to 1% of a given value. When a particular value is recited in the present application and the claims, the term "about" is assumed to mean within an acceptable error range for the particular value, unless otherwise stated.

[0033] The present disclosure may provide a thermal plasma process that may enable the generation of hydrogen and carbon black in an economically feasible manner on a commercial scale. The systems and methods described herein may result in high reaction selectivity (e.g., a hydrogen selectivity of 95% or higher), high conversion rates (e.g., 99% or more of the feedstock can be converted to hydrogen and carbon particles and carbon fouling), and high solid recovery rates (e.g., a recovery rate of 90% or higher of solid carbon and hydrogen). Solid carbon may include carbon particles and carbon fouling. High conversion rates of the feedstock may include conversion rates of about 90%, 92%, 94%, 96%, 98%, 99% or higher. The methods and systems described herein may enable the adjustment of the chemical and physical characteristics of the carbon particles. The methods and systems described herein may enable the generation of hydrogen and carbon particles with lower energy than other methods, such as furnace black or water electrolysis production methods, for example.

[0034] Thermal plasmas can be useful for producing hydrogen without emitting large amounts of carbon dioxide. Thermal plasma technology can be used to convert electrical energy into thermal energy with high efficiency. Thermal plasmas can enable a flexible and controllable supply of thermal energy at high temperatures without or with substantially no carbon dioxide emissions. Thermal plasmas can use various types of gases or gas mixtures. Thermal plasmas can be used in endothermic processes that use high temperatures and can be used in place of combustion processes used in the steel and cement industries, the oil and gas industries, or the chemical and materials industries.

[0035] Thermal plasmas can be used for the thermal decomposition of methane or natural gas to produce hydrogen without or with substantially no production of carbon dioxide. Thermal plasmas can make it possible to produce hydrogen and solid carbon materials without or with no large amounts of carbon dioxide production. The thermal decomposition of methane using thermal plasmas can keep the energy intensiveness lower thermodynamically than other hydrogen production methods such as water dissociation for hydrogen production.

[0036] Large-scale hydrogen production can be advantageous as an alternative fuel. Hydrogen production methods such as steam methane reforming (SMR) can emit large amounts of carbon dioxide. For example, SMR can produce more than an average of 10 tons of carbon dioxide equivalent per ton of hydrogen produced. To reduce the carbon dioxide emitted, a carbon capture and storage (CCS) system can be used in parallel with SMR, but these methods may not be usable on an industrial scale.

[0037] For the production of decarbonized hydrogen (e.g., hydrogen production without carbon by-products or carbon products), water electrolysis can be an option. Water electrolysis can be energy-intensive in that it can use at least about 285 kilojoules (kJ / mol) per mole of hydrogen produced.

[0038] The route based on the thermal decomposition of methane at high temperature to produce solid carbon and hydrogen can be as shown in Equation 1. CH4 → C + 2H2 76 kJ / Mol (1) At high temperatures, methane can be decomposed into molecular constituents of carbon and hydrogen gas. One mole of hydrogen produced from methane is associated with an energy of 38 kJ / mol. Since two moles of hydrogen can be produced from one mole of methane, approximately 76 kJ / mol can be used in the thermal decomposition reaction. In the thermal decomposition of methane, approximately one-seventh of the energy per mole of hydrogen produced can be used (e.g., 38 kJ / mol vs. 285 kJ / mol). In addition, the thermal decomposition of methane can enable the production of two recoverable products, solid carbon and hydrogen.

[0039] Hot-wall thermal decomposition may be used for the thermal decomposition of methane. The hydrogen produced by this method can burn during the aerobic stage and provide part of the energy used for the thermal decomposition of the raw material in the anaerobic stage. In this method, if hydrogen is used during the heating cycle, it may not be possible to produce hydrogen on a commercial scale. For example, for commercial-scale hydrogen production, electric heating rather than hydrogen may be used during the aerobic stage. In hydrogen production using hot-wall thermal decomposition, gaseous emissions containing impurities such as sulfur oxides and nitrogen oxides may be generated. Treating the gaseous emissions to remove impurities can increase the complexity and cost of hydrogen production.

[0040] Alternatively, thermal catalytic decomposition may be used for the thermal decomposition of methane. In some cases, despite the moderate endothermicity of methane thermal decomposition, high operating temperatures may be used for methane thermal decomposition due to the stability of methane. By using a catalyst, it may be possible to decompose methane at a lower temperature. By using a metal catalyst, the complexity of hydrogen and carbon production may increase due to the rapid deactivation of such a catalyst and the difficulty of separating the catalyst from the solid carbon produced. Carbon-based catalysts may have catalytic activity for sustaining the decomposition of methane above 800 °C in an operating range of about 800 - 900 °C. Carbon catalysts may deactivate, but the service life can be longer than that of metal catalysts. The decomposition of methane may not be supported by a carbonaceous catalyst for more than a few hours. By continuously (re)generating catalytically active carbon from catalytically inert carbon, the catalytic active period can be extended. However, this process can be more expensive and less efficient compared to the SMR process. Furthermore, the carbon produced may burn during catalyst regeneration. Highly active catalyst materials may be deactivated by carbon deposition, and such catalyst materials may lack mechanical stability during recycling and use. The purity of the product is reduced not only by the recovery and separation of carbon from the catalyst, but also by carbon contamination by catalyst fragments. Incomplete decomposition of methane at the end of a single pass may increase the complexity of the system due to the implementation of devices for gas separation and recycling.

[0041] Alternatively, molten metal bath pyrolysis may be used for the pyrolysis of methane. Molten metal bath pyrolysis may involve bubbling methane through a hot wall column filled with molten metal. The methane contained in the bubbles may be gradually decomposed while rising in the bath. Next, hydrogen may be discharged from the bath as the off-gas, while solid carbon floats on the liquid surface. Various metals (e.g., Sn, Ga, Bi, Pb, etc.) may be used to enhance heat transfer in the medium while preventing carbon from adhering to the walls. Other metals that enhance heat transfer and have a catalytic effect (e.g., Ni, Fe, Co, Pd, Pt, etc.) may also be used. Many reactive metals have melting points above 1000°C, and inert metals may have melting points above 1000°C, which is similar to the pyrolysis threshold of methane. Therefore, the maximum temperature of the molten bath may be set to about 1000°C, which may result in an upper threshold for the decomposition rate of methane. In addition, in this method, the separation and recovery of low-value forms of carbon that may be contaminated by the metal used in the bath may be difficult.

[0042] Alternatively, solar pyrolysis may be used for the pyrolysis of methane. Concentrated sunlight can be used to heat the walls of the reactor or directly heat the internal gas through floating particles. In this method, either indirect solar heating or direct solar heating may be used. In indirect solar heating, a pyrolysis reactor heated from the outer wall exposed to concentrated sunlight may be used. In direct solar heating, a pyrolysis reactor heated from the inside by light-absorbing particles floating in the process gas may be used. The light-absorbing particles can receive sunlight through the window. The particles can be carbon particles generated by the decomposition of methane or neutral particles used as a heat medium and catalyst. The efficiency of the direct solar heating process may be reduced by the rapid clouding of the window, and the indirect solar heating process may be less efficient due to a low heat yield. The quality control of the carbon produced and the cost of the solar power plant may also reduce the economic viability of such processes on a commercial scale.

[0043] Using non-thermal plasma for the thermal decomposition of methane can be another possible process for producing hydrogen, which enables the decomposition of low-temperature molecules using an electrical process. Since the ionization rate of non-thermal plasma is relatively low, it can be an ionized gas that remains ionized even at low temperatures (e.g., dozens to several hundred degrees Celsius). Non-thermal plasma may have considerable chemical activity due to the presence of high-energy free electrons. Generating non-thermal plasma consumes a large amount of power, which may result in an increase in the electrical cost for producing solid carbon and hydrogen. This technology has the drawback that the conversion of methane to hydrogen is incomplete, which may result in an increase in the capital and process costs for separating hydrogen and recycling unreacted methane. Furthermore, the solid carbon produced together with hydrogen may have relatively low value compared to other methane thermal decomposition processes. Therefore, the use of non-thermal plasma may not be competitive for commercial-scale production of hydrogen and carbon.

[0044] Thermal plasma can enable the conversion of energy from electrical energy to thermal energy. The efficiency of this energy conversion can increase as the size of the plasma generator increases. In contrast to non-thermal plasma, the ionization rate may be high enough to induce Joule heat. Thermal plasma can enable a direct, flexible, and controllable energy supply to the gas volume, potentially without directly emitting carbon dioxide, from high temperatures to ultra-high temperatures. Thermal plasma can be adapted to endothermic processes that use high or ultra-high temperatures within the gas volume.

[0045] Carbon black particles can contain small crystallites with a turbostratic atomic arrangement. Carbon black particles may also contain a graphite-type crystal structure with an interlayer crystal spacing (d002 spacing) similar to that of graphite when compared to turbostratic carbon.

[0046] The properties of carbon black can vary depending on synthesis conditions including, but not limited to, raw materials, heating medium, thermal history, and reactor configuration. In the tire, industrial rubber, and pigment industries, a wide range of carbon nanoparticles are utilized. Carbon nanoparticles can be classified as carbon black that can be characterized by their surface area and structure properties. Depending on the magnitude of both the surface area and structure number, various carbon black grades can be used in various applications, and as a result, have various physical properties and associated economic values. It can be interesting to improve the manufacturing process to acquire the production of a wide range of carbon black grades and utilize pyrolysis and electrical processes rather than conventional combustion-based processes.

[0047] The industrial uses of carbon black properties can vary depending on a number of physicochemical parameters. When used in elastomeric compounds (e.g., tires), the average diameter of the particles and the structure of the carbon black aggregates can be particularly useful. Natural carbon black may have low or no porosity, and thus, there may be a direct relationship between the particle size and the specific surface area measurement (BET) expressed in square meters per gram (m 2 / g). An indicator for quantifying the structure may be the oil absorption number (OAN), which can be the amount of oil in milliliters (mL) per 100 grams (g) of carbon black that a given quantity of carbon black can absorb. The OAN can be measured by adding oil (e.g., dibutyl phthalate (DBP)) to a sample of carbon black while stirring constantly and measuring the resistance to shear. The OAN can be the amount of oil (mL) added per 100 grams of carbon black that produces the maximum resistance to stirring. The procedures of the American Society for Testing and Materials (ASTM), such as ASTM D6556 for total and external surface area by nitrogen adsorption and ASTM D2414 for oil absorption number (OAN), can be utilized to characterize carbon black particles.

[0048] The formation of carbon black by the pyrolysis of methane may follow the ultra-fast continuous dehydrogenation process of various hydrocarbon compounds. The pyrolysis of methane can involve the breaking of C-H bonds by unimolecular decomposition and the subsequent development of thermodynamically more stable C-C and C=C bonds at high temperatures, thus enabling the formation of precursors of alkenes and alkynes. Acetylene is stable at high temperatures and can be a major precursor. The precursors can react with each other to gradually form aromatic compounds or polycyclic aromatic hydrocarbons (PAHs). Although various PAH formation mechanisms can be identified, one of the mechanisms is shown as the H-Abstraction-Acetylene-Addition (HACA) mechanism. As the cluster grows, the dynamics of the HACA mechanism may decrease due to the increasing energy barrier. PAHs can grow in size and may undergo reactions or condensation. In the HACA mechanism, van der Waals forces can play a role. Alternatively or additionally, a high process temperature (e.g., 2000 K) can facilitate the formation of covalent bonds. This initial operation of PAH collisions can be a "nucleation process" using a nucleus composed of 10 to 20 aromatic rings. This nucleation process can form viscous tar nano-droplets by the coalescence collision of the nuclei. The coagulation of these droplets, also called "ripening", can occur not only by the internal rearrangement of PAHs into a turbostratic structure but also by the gradual loss of hydrogen within the particles. The particles can gradually evolve from viscous to solid. When this state is reached, the collision growth mechanism can switch from the coalescence mode to a continuous aggregation process to form larger aggregates and agglomerates with fractal organization. Depending on the type and configuration of the reactor, all of the aforementioned processes can occur sequentially or simultaneously.

[0049] The plasma direct methane decarbonization (DMD) process can enable the simultaneous production of hydrogen and solid carbon while keeping carbon dioxide emissions low by thermally decomposing natural gas or other hydrocarbon feedstocks at very high temperatures using a carbon-free electrical energy source. Such a process can produce hydrogen and high-quality carbon particles (such as carbon black) in yields that have not been achieved before, as described elsewhere in this specification. Furthermore, the carbon particles produced in the plasma DMD process can have characteristics similar to those found in commercially graded furnace carbon black.

[0050] In the plasma DMD process, high-purity hydrocarbon feedstocks (e.g., natural gas) and electricity such as decarbonized electricity can be used. The economic viability of plasma DMD can depend on (i) the cost of natural gas, (ii) the cost of electricity, and (iii) the value of the carbon produced. In such a process, up to 250 kilograms (kg) of hydrogen and 750 kg of carbon particles can be produced per ton of methane. The energy intensity of hydrogen production in a scaled-up plasma DMD process can be less than that of hydrogen production by the water electrolysis process. For example, in the described plasma process, about 18 - 25 kilowatt-hours (kWh / kg H2) can be used per kg of hydrogen produced, whereas in the water electrolysis process it is about 60 kWh / kg H2.

[0051] The reactor systems and methods described herein may enable high yields of carbon particles and hydrogen with less energy and carbon dioxide byproduct generation than other systems and methods. The yields of carbon particles and hydrogen can be increased without increasing the reaction temperature, for example, by diluting the hydrogen produced, such as by removing the hydrogen produced or adding a non-hydrogen gas to the system. Systems with improved yields of carbon and hydrogen may provide viable alternatives to other hydrogen (e.g., water electrolysis, SMR with CCS, etc.) and carbon production (e.g., furnace black, etc.). The production of carbon particles and hydrogen by the thermal plasma processes described herein may provide environmental benefits such as higher carbon intensity and lower energy intensity compared to other processes.

[0052] Carbon particles such as carbon black can be used, for example, to reinforce polymers for tire reinforcement. The performance of carbon black in such applications can be modulated by changes in the surface area and structure of the particles. By modulating or otherwise adjusting the specific surface area and structure of the carbon particles produced, it may be possible to produce particles with predetermined properties. The furnace black reactor can increase the surface area and structure of carbon particles using a raw material mixing or reactor gas quench (e.g., rapid cooling) rate of less than 10 milliseconds after particle formation. Such methods may be insufficient for producing high surface area particles in a plasma pyrolysis process. The methods and systems described herein can be used to produce high surface area and otherwise adjustable carbon particles using plasma pyrolysis. For example, the surface area of carbon particles produced using a gas phase hydrocarbon can be increased by reducing the hydrogen content of the gas mixture or increasing the average molecular weight of the reaction gas (e.g., plasma gas). Reducing the hydrogen content in the reactor can provide additional operational benefits such as enabling a higher product yield at a lower reaction temperature compared to similar systems with a high hydrogen content, accelerating the conversion of hydrocarbons to carbon and hydrogen, reducing reactor fouling, or reducing hydrogen erosion of reactor components. Systems and methods for producing carbon particles

[0053] In one aspect, the present disclosure provides a method for producing carbon particles. The method may include contacting a non-hydrogen gas with a hydrocarbon feedstock in the presence of a plasma in a reactor to produce carbon particles and an exhaust gas. The exhaust gas may include hydrogen, a non-hydrogen gas, or both. At least a portion of the hydrogen can be separated from the non-hydrogen gas of the exhaust gas to obtain a separated gas containing the non-hydrogen gas. The separated gas or a derivative thereof can be provided to the reactor. In the reactor, the separated gas or a derivative thereof can be contacted with a further hydrogen feedstock in the presence of a plasma to produce further carbon particles and a further exhaust gas containing hydrogen and a non-hydrogen gas.

[0054] The present disclosure provides systems and methods for affecting chemical changes. Affecting such chemical changes can include, for example, generating a carbonaceous material, hydrogen, or a combination thereof using the systems and methods described herein. The carbonaceous material may be solid. The carbonaceous material may include, for example, carbon particles, carbon-containing compounds, or a combination thereof, or may be those. The carbonaceous material may include, for example, carbon black. The systems (e.g., apparatuses) and methods of the present disclosure, as well as the processes implemented using the systems and methods herein, may enable, for example, the continuous generation of a carbonaceous material, hydrogen, or a combination thereof. The process may include converting a feedstock (e.g., one or more hydrocarbons). The systems and methods described herein may include rapidly heating one or more hydrocarbons to form, for example, a carbonaceous material, hydrogen, or a combination thereof. For example, one or more hydrocarbons can be rapidly heated to form carbon particles, hydrogen, or a combination thereof. Hydrogen may, in some cases, refer to mostly hydrogen (H2). For example, some portions of this hydrogen may contain methane (e.g., unused methane) or various other hydrocarbons (e.g., ethane, propane, ethylene, acetylene, benzene, toluene, polycyclic aromatic hydrocarbons (PAHs), such as naphthalene, etc.). The hydrocarbons may also be in the form of renewable natural gas, biogas, tall oil, pine resin, biodiesel, or their precursors or derivatives, or other bio-derived carbonaceous feedstocks. The feedstock may be solid and can be any solid, for example, that can be treated with plasma upstream of the conversion vessel to provide a gaseous or liquid fuel feedstock to the process.

[0055] The present disclosure provides examples of such systems and methods that include, for example, using plasma technology when pyrolyzing (e.g., pyrolytic dehydrogenating) natural gas into a carbonaceous material (e.g., a solid carbonaceous material, such as carbon particles), hydrogen, or a combination thereof. Pyrolysis (e.g., pyrolytic dehydrogenating) can refer to the thermal decomposition of a material at an elevated temperature (e.g., a temperature higher than about 800 °C) in an inert or oxygen-free environment or atmosphere. The temperature of the reactor can be increased to increase the conversion of the feedstock into carbon particles, hydrogen, or a combination thereof. The temperature of the reactor can be increased to selectively produce hydrogen, carbon particles, or a combination thereof. The temperature of the reactor can be adjusted to increase or decrease the surface area of the carbon particles. Increasing the temperature not only increases the rate of decomposition of the feedstock, but can also increase the intermediate operations leading to the formation of carbon particles and hydrogen. Increasing the temperature of the reactor can increase the aging rate of the carbon particles and reduce fouling of the reactor walls. This may be due to the reduced time until the carbon particles become chemically inert.

[0056] The systems and processes described herein may include, but are not limited to, a series of unit operations such as the treatment of reaction products, the separation of solid and gaseous products, the purification of gas streams, or any combination thereof. The carbon and hydrogen production system may include, but is not limited to, a reactor unit, a heat exchanger unit, a filter unit, a pelletizer unit, a gas purification unit, or any combination thereof. The gas purification unit may include a pressure swing adsorption process, a membrane separation unit, an absorption or stripper separation unit, a cryogenic separation unit, a gas compressor, an impurity removal system, or any combination thereof. The purification of the gas and its reinjection into the reactor provides a broader ability to produce a wider range of useful carbon particle (e.g., carbon black) grades, increasing the product yield and reducing the raw material cost. The recycled and purified reaction gas can be recycled to the plasma generating electrodes of the reactor. Alternatively or additionally, externally supplied gas may be delivered to the plasma and the reaction vessel. The plasma arc characteristics, the formation of carbon nanostructures, the physical properties of the carbon nanostructures, or any combination thereof can be modified by the composition of the supplied gas, the flow rate of the supplied gas, the gas density, and other process factors. By controlling the molecular weight and composition of the gas delivered to the reactor, the ability to produce carbon nanostructures is extended, the overall yield is improved, and the raw material cost for plasma pyrolysis to produce solid carbon particles and hydrogen can be reduced.

[0057] Figure 1 schematically shows an example of a bench-scale three-phase plasma pyrolysis system for generating carbon particles and hydrogen. Bench-scale three-phase plasma pyrolysis can include a gas supply system, a plasma source, a pyrolysis reactor, a filter system, a water-cooled bench, an output gas analysis bench, or any combination thereof. The gas supply system can manage the routing of the input gas, which can include, but is not limited to, hydrogen, nitrogen, carbon monoxide, carbon dioxide, argon, krypton, neon, methane, or any combination thereof. The gas supply system can provide a non-hydrogen gas, a hydrogen gas, or both to the reactor before injecting the hydrocarbon feedstock. In one example, a non-hydrogen gas or a hydrogen gas can be provided to the reactor through or adjacent to the plasma generating electrode to enable the generation of plasma. The electrode can have one or more fluid flow paths that allow a non-hydrogen gas or a hydrogen gas to flow through the electrode(s). A non-hydrogen gas (e.g., nitrogen, argon, etc.) can be used to generate plasma, and the plasma can be used to heat the reactor. The gas supply system can provide a hydrocarbon feedstock to the system. The hydrocarbon feedstock can be provided with a non-hydrogen gas or a hydrogen gas, or separately from a non-hydrogen gas or a hydrogen gas. As shown in Figure 1, the hydrocarbon feedstock can be provided to the reactor downstream of the non-hydrogen gas or the hydrogen gas. The carbon particles and the exhaust gas can be provided to a quench unit configured to cool the solid and gas products for downstream processing. The solid material can be separated from the gaseous material, and in some cases, at least a portion of the gaseous material can be recycled or otherwise returned to the reactor.

[0058] Hydrogen or non-hydrogen gas can be heated using electrical energy (e.g., from a DC or AC power source). The electrical energy can be provided by one or more plasma generating electrodes disposed in the plasma generating section of the reactor. The one or more plasma generating electrodes may be configured to heat, or be capable of heating, the heat transfer gas within the plasma generating section. Any description herein regarding heating of a gas or gases can equally apply, in at least some configurations, to heating a gas mixture having a corresponding composition (e.g., a gas of at least 50 volume %). The gas mixture can include, for example, a mixture of individual gases, liquids, or a mixture of individual gas-liquid mixtures. Any description herein regarding a gas can equally apply, in at least some configurations, to a liquid or gas-liquid mixture having a corresponding composition. One or more gases can be heated by an electric arc. The arc can be controlled by using a magnetic field that can rapidly move the arc circularly around the tip of the electrode. The electrodes may or may not be oriented parallel to the axis of the reactor or to each other. The electrode(s) can include complex shapes. Hydrocarbons (e.g., feedstock) can be injected through various injector configurations. For example, hydrocarbons (e.g., feedstock) can be injected into the injector through the center of concentric electrodes.

[0059] The systems described herein may include a plasma generator. The plasma generator can utilize a gas (e.g., a plasma gas, a reactor gas, etc.) or a gas mixture (e.g., a gas of at least 50% by volume). The plasma generator can utilize a gas or a gas mixture (e.g., a gas of at least 50% by volume), in which case the gas is reactive and corrosive in a plasma state. The plasma generator may be a plasma torch. The systems described herein may include a plasma generator energized by a DC or AC power source. The gas or gas mixture can be supplied directly to the band where the discharge generated by the DC or AC power source persists. The plasma may have a composition described elsewhere herein (e.g., with respect to the composition of one or more gases). The plasma can be generated using arc heating. The plasma can be generated using induction heating. The plasma can be generated using a DC electrode. The plasma can be generated using an AC electrode. For example, a plurality of (e.g., three or more) AC electrodes can be used (e.g., having the advantages of not only more efficient energy consumption but also reduced heat load on the electrode surface).

[0060] The plasma generator can operate at a suitable power. The power can be, for example, about 0.5 kilowatts (kW), 1 kW, 1.5 kW, 2 kW, 5 kW, 10 kW, 25 kW, 50 kW, 75 kW, 100 kW, 150 kW, 200 kW, 250 kW, 300 kW, 350 kW, 400 kW, 450 kW, 500 kW, 550 kW, 600 kW, 650 kW, 700 kW, 750 kW, 800 kW, 850 kW, 900 kW, 950 kW, 1 megawatt (MW), 1.05 MW, 1.1 MW, 1.15 MW, 1.2 MW, 1.25 MW, 1.3 MW, 1.35 MW, 1.4 MW, 1.45 MW, 1.5 MW, 1.6 MW, 1.7 MW, 1.8 MW, 1.9 MW, 2 MW, 2.5 MW, 3 MW, 3.5 MW, 4 MW, 4.5 MW, 5 MW, 5.5 MW, 6 MW, 6.5 MW, 7 MW, 7.5 MW, 8 MW, 8.5 MW, 9 MW, 9.5 MW, 10 MW, 10.5 MW, 11 MW, 11.5 MW, 12 MW, 12.5 MW, 13 MW, 13.5 MW, 14 MW, 14.5 MW, 15 MW, 16 MW, 17 MW, 18 MW, 19 MW, 20 MW, 25 MW, 30 MW, 35 MW, 40 MW, 45 MW, 50 MW, 55 MW, 60 MW, 65 MW, 70 MW, 75 MW, 80 MW, 85 MW, 90 MW, 95 MW or 100 MW or even greater.Alternatively or additionally, the power may be, for example, about 100 MW, 95 MW, 90 MW, 85 MW, 80 MW, 75 MW, 70 MW, 65 MW, 60 MW, 55 MW, 50 MW, 45 MW, 40 MW, 35 MW, 30 MW, 25 MW, 20 MW, 19 MW, 18 MW, 17 MW, 16 MW, 15 MW, 14.5 MW, 14 MW, 13.5 MW, 13 MW, 12.5 MW, 12 MW, 11.5 MW, 11 MW, 10.5 MW, 10 MW, 9.5 MW, 9 MW, 8.5 MW, 8 MW, 7.5 MW, 7 MW, 6.5 MW, 6 MW, 5.5 MW, 5 MW, 4.5 MW, 4 MW, 3.5 MW, 3 MW, 2.5 MW, 2 MW, 1.9 MW, 1.8 MW, 1.7 MW, 1.6 MW, 1.5 MW, 1.45 MW, 1.4 MW, 1.35 MW, 1.3 MW, 1.25 MW, 1.2 MW, 1.15 MW, 1.1 MW, 1.05 MW, 1 MW, 950 kW, 900 kW, 850 kW, 800 kW, 750 kW, 700 kW, 650 kW, 600 kW, 550 kW, 500 kW, 450 kW, 400 kW, 350 kW, 300 kW, 250 kW, 200 kW, 150 kW, 100 kW, 75 kW, 50 kW, 25 kW, 10 kW, 5 kW, 2 kW, 1.5 kW or 1 kW or less.

[0061] The raw materials can be provided to the reactor. At least one reaction gas (e.g., any non-raw material gas provided to the reactor in accordance with the present disclosure) can be provided to the reactor. By using a heat generator (e.g., at the top of the reactor or the plasma generation section), a high-temperature gas can be generated (e.g., within the reactor or the plasma generation section). For example, the high-temperature gas can be generated at the top of the reactor by using one or more AC electrodes (e.g., three or more AC electrodes), a DC electrode (e.g., concentric DC electrodes), or a resistance heater or an induction heater. The high-temperature gas can be generated by heating at least a subset of one or more types of gases (e.g., the raw material alone or in combination with at least one process gas) using an AC electrode, a DC electrode, or a resistance heater or an induction heater. The heating can include directly heating a hydrocarbon (e.g., the raw material). For example, the hydrocarbon (e.g., the raw material) can be added to the heat generator (e.g., at the pressure described elsewhere in this specification). For example, the hydrocarbon (e.g., the raw material) can be added by direct injection into the plasma. The reactor (or at least a part thereof, such as at least a part of the inner wall of the reactor) can include a liner (e.g., a refractory liner). The hydrocarbon (e.g., the raw material) can be provided to the reactor. For example, the hydrocarbon (e.g., the raw material) can be injected into the reactor via one or more injectors. Alternatively or additionally, the hydrocarbon (e.g., the raw material) can be provided via one or more inlet ports (e.g., the wall of the reactor). The hydrocarbon can be injected at or near the plasma generation source point (e.g., adjacent to the plasma generation electrode(s)) or downstream or upstream of the heat plasma source. Any description herein regarding the number or position of the injectors can equally apply to the inlet ports, at least in some configurations, and vice versa. One or more types of process gases can be provided via one or more inlet ports (e.g., the same as or different from the hydrocarbon or the raw material) or via at least a subset of one or more injectors.A given process gas can be provided together with the raw material, separately from the raw material, or in a combination thereof (e.g., a given process gas can be provided together with the raw material, and either the given process gas or another process gas can be provided separately from the raw material (e.g., as a purge)). The given process gas may or may not be heated by a heat generator.

[0062] The process gas provided with or in parallel with the raw material can be heated. The process gas can modify the environment or atmosphere inside or around at least a part of the reactor, heat generator, inlet port(s), or injector(s), purge at least a part of the reactor, heat generator, inlet port(s), or injector(s), or any combination thereof. For example, an inlet port, a series of inlet ports, or a plenum (e.g., the upper part of the reactor) can be used to purge at least a part of the reactor (e.g., one or more walls), one or more other inlet ports, or one or more injectors (as described in more detail elsewhere in this specification). Any description of the inlet ports herein can equally apply to a series of inlet ports or a plenum in at least some configurations, and vice versa. One or more gases heated with electrical energy (e.g., the raw material alone or in combination with at least one process gas) can contain substantially only hydrocarbons (e.g., the raw material). For example, one or more gases heated with electrical energy can contain the raw material, may not contain a process gas, or may contain purge level(s) of process gas(es) or some process gas(es) added with the raw material (e.g., one or more gases heated with electrical energy can contain the raw material and purge level(s) of process gas(es)). When the hydrocarbon being heated (e.g., the raw material) contains substantially only newly supplied hydrocarbons, such a configuration can be referred to herein as an "once-through process". Alternatively, one or more gases heated with electrical energy can contain higher level(s) of process gas(es). The level of a given process gas, or the total of a subset or all process gases (e.g., on a per mole of raw material basis) and the percentage of process gas heated with electrical energy can be as described elsewhere in this specification. In some cases where DC electrodes are used, two electrodes can be used.In some cases where DC electrodes are used, multiples of two electrodes (e.g., 2, 4, 6, etc.) can be used. AC electrodes can be used in single-phase or three-phase configurations. When a single-phase AC configuration is used, multiples of two electrodes (e.g., 2, 4, 6, 8, etc.) can be used. When a three-phase AC configuration is used, multiples of three electrodes (e.g., 3, 6, 9, etc.) can be used. Each electrode can have an associated injector. For example, a three-phase three-electrode configuration can include three injectors placed on the plane of the electrodes.

[0063] The electrode may be cylindrical. The electrode may be movable via a screw system that operates in conjunction with a slide seal associated with the electrode. The screw system may be water-cooled. The use of a movable electrode may enable continuous operation of the reactor. For example, additional electrode material can be joined to the end of the electrode outside the reactor, and when the electrode deteriorates within the reactor, new electrode material can be supplied into the reactor. In this example, by being able to add new electrode material outside the reactor during operation of the reactor, continuous or substantially continuous operation of the reactor can be provided. In some cases, the electrode includes graphite (e.g., synthetic graphite, natural graphite, semi-graphite, etc.), a carbonaceous material and a resin or other binder, a carbon composite material, a carbon fiber material, etc., or any combination thereof. The electrode may have a diameter of at least about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 35, 40 inches or greater. The electrode may have a diameter of at most about 40, 35, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 inch or less. The electrode may have a length of at least about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 feet or greater. The electrode may have a length of at most about 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 feet or less. The distance between the center point of the electrode arc and the reactor wall may be at least about 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4 meters or greater.The distance between the center point of the electrode arc and the wall of the reactor may be at most about 4, 3.9, 3.8, 3.7, 3.6, 3.5, 3.4, 3.3, 3.2, 3.1, 3, 2.9, 2.8, 2.7, 2.6, 2.5, 2.4, 2.3, 2.2, 2.1, 2, 1.9, 1.8, 1.7, 1.6, 1.5, 1.4, 1.3, 1.2, 1.1, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1 meters or less. If the distance is too large, the gas may recirculate back into the plasma region, while if the distance is too small, degradation of the reactor wall may be caused. In some cases, the electrode can have a mass of at least about 20, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1,000, 10,000, 20,000, 30,000, 40,000 kilograms or more. In some cases, the electrode can have a mass of at most about 40,000, 30,000, 20,000, 10,000, 1,000, 900, 800, 700, 600, 500, 400, 300, 200, 100, 20 kilograms or less.

[0064] An electrode (e.g., an AC or DC electrode of a plasma generator) (or a part thereof) according to the present disclosure may be placed at a given distance (also referred to herein as "gap" or "gap size") from each other. The gap between the electrodes (or a part thereof) may be, for example, about 40 millimeters (mm), 39 mm, 38 mm, 37 mm, 36 mm, 35 mm, 34 mm, 33 mm, 32 mm, 31 mm, 30 mm, 29 mm, 28 mm, 27 mm, 26 mm, 25 mm, 24 mm, 23 mm, 22 mm, 21 mm, 20 mm, 19 mm, 18 mm, 17 mm, 16 mm, 15 mm, 14 mm, 13 mm, 12 mm, 11 mm, 10 mm, 9 mm, 8 mm, 7 mm, 6 mm, 5 mm, 4 mm, 3 mm, 2 mm or 1 mm or less. Alternatively or additionally, the gap between the electrodes (or a part thereof) may be, for example, about 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, 20 mm, 21 mm, 22 mm, 23 mm, 24 mm, 25 mm, 26 mm, 27 mm, 28 mm, 29 mm, 30 mm, 31 mm, 32 mm, 33 mm, 34 mm or 35 mm or greater.

[0065] The reactor may include the wall(s) of one or more reactors. The outer boundary (e.g., the wall of the reactor) may include a liquid or gas-cooled double-wall container. In one example, the wall of the reactor includes a liquid-cooled double-wall container. Thermal energy may be removed from the reactor by a cooling circuit coupled to the reactor vessel. Thermal energy may be removed at a rate that maintains the thermal steady state of the reactor. The walls of the container may be thermally stable and formed from any material with thermal conductivity, such as stainless steel, carbon steel, mild steel, nickel alloy, or any combination thereof. In one example, the container is formed from stainless steel.

[0066] The hydrocarbon feedstock can be injected adjacent to one or more electrodes. The hydrocarbon can be injected in the immediate vicinity of one or more electrodes. In some cases, the hydrocarbon is injected at a distance of from about 1 mm to about 1,000 mm from the electrode. In some cases, the hydrocarbon is injected at a distance of from about 1 mm to about 5 mm, from about 1 mm to about 10 mm, from about 1 mm to about 100 mm, from about 1 mm to about 1,000 mm, from about 5 mm to about 10 mm, from about 5 mm to about 100 mm, from about 5 mm to about 1,000 mm, from about 10 mm to about 100 mm, from about 10 mm to about 1,000 mm, or from about 100 mm to about 1,000 mm from the electrode. In some cases, the hydrocarbon is injected at a distance of about 1 mm, about 5 mm, about 10 mm, about 100 mm, or about 1,000 mm from the electrode. In some cases, the hydrocarbon is injected at a distance of at least about 1 mm, about 5 mm, about 10 mm, or about 100 mm from the electrode. In some cases, the hydrocarbon is injected at a distance of up to about 5 mm, about 10 mm, about 100 mm, or about 1,000 mm from the electrode.

[0067] The pressure at the tip of any injector may be the same as the pressure of the surrounding reactor. In some cases, the pressure at the tip of any injector is greater than the pressure of the surrounding reactor. In some cases, the pressure at the tip of any injector is within 20% of the pressure of the surrounding reactor. In some cases, the pressure at the tip of any injector is within 10% of the pressure of the surrounding reactor. In some cases, the pressure at the tip of any injector is within 5% of the pressure of the surrounding reactor. In some cases, the pressure at the tip of any injector is within 1% of the pressure of the surrounding reactor.

[0068] The electrode, injector, or both can have an inclination angle of at least about 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90 degrees or greater (e.g., the angle between the long axis of the electrode or injector and the long axis of the reactor). The electrode or injector can have a maximum inclination angle of about 90, 85, 80, 75, 70, 65, 60, 55, 50, 45, 40, 35, 30, 25, 20, 15, 10, 5, 0 degrees or less. The electrode or injector can have an inclination angle within the range defined by any two of the foregoing values. For example, the electrode and injector can have an inclination angle between about 15 and about 30 degrees. The greater the inclination angle, the greater the stability of the torch can be. The injector can be inclined or positioned in such a way as to provide a tangential component to the injection rate. The injector can include a heat-resistant material (e.g., metal, tungsten, graphite, metal carbide, ceramic material, alumina, silica, aluminosicate, glass, etc.). For example, the injector can be formed from a metal (copper, stainless steel, Inconel, etc.). The injector can be water-cooled. The injector can be configured to provide additional additives to the reactor in addition to the raw materials.

[0069] The injector (or a part thereof) according to the present disclosure may include or be one or more suitable materials such as, for example, copper, stainless steel, graphite, alloys (e.g., high-temperature corrosion-resistant metals) or other similar materials (e.g., having a high melting point and good corrosion resistance), or such materials. The injector(s) can be cooled by a coolant. The injector(s) can be cooled, for example, by water or a non-oxidizing liquid (e.g., mineral oil, ethylene glycol, propylene glycol, synthetic organic fluids such as DOWTHERM™ materials, etc.). The injector can also be cooled by a gas (e.g., hydrogen, nitrogen, helium, argon, etc.).

[0070] The reactor may include or be capable of injecting one or more injectors configured to inject into the reactor a non-hydrogen gas, a hydrocarbon feedstock, a separation gas, or any combination thereof. The one or more injectors may be substantially the same or the same. Alternatively or additionally, the individual gases injected into the reactor may be injected via an injector configured to inject a specific gas or gas mixture. For example, each type of gas injected may be injected via a unique injector configured for that specific gas or gas mixture. The injector may be designed or modified based on the physical properties of the gas or gas mixture injected into the reactor. The injector may be designed such that a uniform stream of the gas or gas mixture can pass through the outlet port of the injector, and thus the total flow rate of the inlet gas through all injectors matches an orthogonal, partially orthogonal, or parallel flow of the process gas within the reactor. By adjusting the flow of the process gas within the reactor, the carbon particles generated can be adjusted. In one example, the feedstock includes a liquid component and a liquid spray assembly is included in the nozzle design of the injector. The liquid spray assembly may be capable of delivering droplets of a size of 10 microns or greater. In one example, the feedstock includes a gaseous phase liquid component(s) and the injector assembly may be heated or insulated to prevent the liquid from condensing on the inner surface of the injector. The non-hydrogen gas may be injected into the system as a heat medium that can be mixed with the carbonaceous feedstock. The non-hydrogen gas injector may be a plenum at the top of the plasma chamber that supplies gas in a primary gas flow through the sheath, annulus, or center of the electrode for a concentric ring DC2 electrode system. For an AC system, the gas may be supplied directly to the plasma generated by the electrodes via the plenum. The injector or plenum may be configured to mix the gases or otherwise distribute the gas through the reactor.

[0071] One or more additives can be added to the reactor via an injector. The additives can be added to the reactor in parallel with the hydrocarbon feedstock (e.g., via the same injector) or via different injectors. The one or more additives can include one or more suitable compounds (e.g., in a vaporized state; in a molten state; dissolved in water, an organic solvent (e.g., a liquid feedstock, ethylene glycol, diethylene glycol, propylene glycol, diethyl ether or other similar ethers, or other suitable organic solvents), or a mixture thereof, etc.). For example, a structure (e.g., DBP) can be at least partially controlled by utilizing suitable ionic compounds such as alkali metal salts (e.g., acetate, adipate, ascorbate, benzoate, bicarbonate, carbonate, citrate, dehydroacetate, erythorbate, ethyl para-hydroxybenzoate, formate, fumarate, gluconate, hydrogen acetate, hydroxide, lactate, malate, methyl para-hydroxybenzoate, orthophenylphenol, propionate, propyl para-hydroxybenzoate, sorbate, succinate, or tartrate) of sodium, potassium, rubidium or cesium. By adding an ionic compound to the reactor during particle formation, particle aggregation may be disrupted and the structure of the carbon particles may be reduced. In one example, an additive such as potassium is added to the reactor. In another example, no additive is added to the reactor.Such compound(s) can be added at suitable levels with respect to (or in relation to) the feedstock and / or heat transfer gas (e.g., the compound(s) can be added at a ratio or concentration, on a molar or mass basis, of about 0 ppm to 2 ppm, 0 ppm to 5 ppm, 0 ppm to 10 ppm, 0 ppm to 20 ppm, 0 ppm to 50 ppm, 0 ppm to 100 ppm, 0 ppm to 200 ppm, 0 ppm to 500 ppm, 0 ppm to 1000 ppm, 0 ppm to 2000 ppm, 0 ppm to 5000 ppm, 0 ppm to 1%, 5 ppm to 50 ppm, 10 ppm to 100 ppm, 20 ppm to 100 ppm, 100 ppm to 200 ppm, 100 ppm to 500 ppm, 200 ppm to 500 ppm, 10 ppm to 2000 ppm, 100 ppm to 5000 ppm, 1000 to 2000 ppm, 2000 ppm to 5000 ppm, 2000 ppm to 1%, or 5000 ppm to 1% with respect to, for example, the feedstock flow rate and / or heat gas flow rate, or the amount of carbon added with the feedstock).

[0072] The hydrocarbon feedstock has the formula C n H x or C n H x O yAny chemical substance having, where n is an integer, x is (i) between 1 and 2n + 2 or (ii) less than 1 in the case of fuels such as coal, coal tar, pyrolysis fuel oil, etc., and y is between 0 and n. The hydrocarbon raw material may include, for example, simple hydrocarbons (such as methane, ethane, propane, butane, etc.), aromatic raw materials (such as benzene, toluene, xylene, methylnaphthalene, pyrolysis fuel oil, coal tar, coal, heavy oil, oil, bio-oil, biodiesel, other hydrocarbons biologically derived, etc.), unsaturated hydrocarbons (such as ethylene, acetylene, butadiene, styrene, etc.), oxygenated hydrocarbons (such as ethanol, methanol, propanol, phenol, ketone, ether, ester, etc.), or any combination thereof. These examples are provided as non-limiting examples of acceptable hydrocarbon raw materials that can be further combined or mixed with other components for production. The hydrocarbon raw material may refer to a raw material in which most of the raw material (e.g., more than about 50% by weight) has the properties of a hydrocarbon. The reactive hydrocarbon raw material may contain at least about 70% by weight of methane, ethane, propane, or a mixture thereof. The hydrocarbon raw material may contain natural gas or may be natural gas. The hydrocarbon may contain methane, ethane, propane, or a mixture thereof. The hydrocarbon may contain methane, ethane, propane, butane, acetylene, ethylene, carbon black oil, coal tar, crude coal tar, diesel oil, benzene, or methylnaphthalene. The hydrocarbon may contain (e.g., further) polycyclic aromatic hydrocarbons. The hydrocarbon raw material may contain one or more simple hydrocarbons, one or more aromatic raw materials, one or more unsaturated hydrocarbons, one or more oxygenated hydrocarbons, or any combination thereof.The hydrocarbon feedstock can include, for example, methane, ethane, propane, butane, pentane, natural gas, benzene, toluene, xylene, ethylbenzene, naphthalene, methylnaphthalene, dimethylnaphthalene, anthracene, methylanthracene, other monocyclic or polycyclic aromatic hydrocarbons, carbon black oil, diesel oil, pyrolysis fuel oil, coal tar, crude coal tar, coal, heavy oil, oil, bio-oil, biodiesel, other biologically derived hydrocarbons, ethylene, acetylene, propylene, butadiene, styrene, ethanol, methanol, propanol, phenol, one or more ketones, one or more ethers, one or more esters, one or more aldehydes, or any combination thereof. The feedstock can include one or more derivatives of the feedstock compounds described herein, such as derivatives of benzene or its derivatives, naphthalene or its derivatives, anthracene or its derivatives. The hydrocarbon feedstock (also referred to herein as "feedstock") can be present in a given feedstock (e.g., among the aforementioned feedstocks) at a concentration of about 1 ppm, 5 ppm, 10 ppm, 25 ppm, 50 ppm, 0.01%, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95% or 99% or higher by weight, volume, or mole (e.g., in a mixture of feedstocks).Alternatively or additionally, the feedstock may comprise a given feedstock at a concentration of about 100%, 99%, 95%, 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, 50%, 49%, 48%, 47%, 46%, 45%, 44%, 43%, 42%, 41%, 40%, 39%, 38%, 37%, 36%, 35%, 34%, 33%, 32%, 31%, 30%, 29%, 28%, 27%, 26%, 25%, 24%, 23%, 22%, 21%, 20%, 19%, 18%, 17%, 16%, 15%, 14%, 13%, 12%, 11%, 10%, 9%, 8%, 7%, 6%, 5%, 4.5%, 4%, 3.5%, 3%, 2.5%, 2%, 1.9%, 1.8%, 1.7%, 1.6%, 1.5%, 1.4%, 1.3%, 1.2%, 1.1%, 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, 0.1%, 0.05%, 0.01%, 50 ppm, 25 ppm, 10 ppm, 5 ppm or 1 ppm or less (e.g., in a mixture of feedstocks). The feedstock may comprise additional feedstocks at similar or different concentrations (e.g., as a mixture of feedstocks). Such additional feedstocks may be selected, for example, from among the aforementioned feedstocks not selected as the given feedstock. The given feedstock itself may comprise a mixture (e.g., natural gas, etc.).

[0073] The hydrocarbon feedstock can be provided to the system at a rate of, for example, about 50 grams per hour (g / hr), 100 g / hr, 250 g / hr, 500 g / hr, 750 g / hr, 1 kilogram per hour (kg / hr), 2 kg / hr, 5 kg / hr, 10 kg / hr, 15 kg / hr, 20 kg / hr, 25 kg / hr, 30 kg / hr, 35 kg / hr, 40 kg / hr, 45 kg / hr, 50 kg / hr, 55 kg / hr, 60 kg / hr, 65 kg / hr, 70 kg / hr, 75 kg / hr, 80 kg / hr, 85 kg / hr, 90 kg / hr, 95 kg / hr, 100 kg / hr, 150 kg / hr, 200 kg / hr, 250 kg / hr, 300 kg / hr, 350 kg / hr, 400 kg / hr, 450 kg / hr, 500 kg / hr, 600 kg / hr, 700 kg / hr, 800 kg / hr, 900 kg / hr, 1,000 kg / hr, 1,100 kg / hr, 1,200 kg / hr, 1,300 kg / hr, 1,400 kg / hr, 1,500 kg / hr, 1,600 kg / hr, 1,700 kg / hr, 1,800 kg / hr, 1,900 kg / hr, 2,000 kg / hr, 2,100 kg / hr, 2,200 kg / hr, 2,300 kg / hr, 2,400 kg / hr, 2,500 kg / hr, 3,000 kg / hr, 3,500 kg / hr, 4,000 kg / hr, 4,500 kg / hr, 5,000 kg / hr, 6,000 kg / hr, 7,000 kg / hr, 8,000 kg / hr, 9,000 kg / hr or 10,000 kg / hr or faster.Alternatively or additionally, the feedstock (e.g., hydrocarbon) can be provided to the system (e.g., the reactor) at a rate of, for example, about 10,000 kg / hr, 9,000 kg / hr, 8,000 kg / hr, 7,000 kg / hr, 6,000 kg / hr, 5,000 kg / hr, 4,500 kg / hr, 4,000 kg / hr, 3,500 kg / hr, 3,000 kg / hr, 2,500 kg / hr, 2,400 kg / hr, 2,300 kg / hr, 2,200 kg / hr, 2,100 kg / hr, 2,000 kg / hr, 1,900 kg / hr, 1,800 kg / hr, 1,700 kg / hr, 1,600 kg / hr, 1,500 kg / hr, 1,400 kg / hr, 1,300 kg / hr, 1,200 kg / hr, 1,100 kg / hr, 1,000 kg / hr, 900 kg / hr, 800 kg / hr, 700 kg / hr, 600 kg / hr, 500 kg / hr, 450 kg / hr, 400 kg / hr, 350 kg / hr, 300 kg / hr, 250 kg / hr, 200 kg / hr, 150 kg / hr, 100 kg / hr, 95 kg / hr, 90 kg / hr, 85 kg / hr, 80 kg / hr, 75 kg / hr, 70 kg / hr, 65 kg / hr, 60 kg / hr, 55 kg / hr, 50 kg / hr, 45 kg / hr, 40 kg / hr, 35 kg / hr, 30 kg / hr, 25 kg / hr, 20 kg / hr, 15 kg / hr, 10 kg / hr, 5 kg / hr, 2 kg / hr, 1 kg / hr, 750 g / hr, 500 g / hr, 250 g / hr or 100 g / hr or less.

[0074] A non-hydrogen gas can be provided to the reactor for a time sufficient for the reactor to reach a thermal steady state, where there is plasma present and no hydrocarbon feedstock present. The flow rate of the non-hydrogen gas to reach the steady state may be equal to or substantially equal to the flow rate during the production of carbon particles and the exhaust gas. Alternatively, a first flow rate may be used during reactor heating and the flow rate may be adjusted or modified during carbon particle production. In one example, the flow rate of the non-hydrogen gas during heating may be greater than the flow rate of the non-hydrogen gas during carbon particle production. In another example, the flow rate of the non-hydrogen gas during heating may be less than the flow rate of the non-hydrogen gas during carbon particle production. The flow rate of the non-hydrogen gas may be as described elsewhere in this specification. The time to reach the thermal steady state can depend on the size of the reactor, the flow rate of the non-hydrogen gas, and the power provided to the plasma generating electrodes. The time may be about 10 hours (h) or less, 8 h, 6 h, 5 h, 4 h, 3 h, 2 h, 1 h, or less. The time may be about 1 h or longer, 2 h, 3 h, 4 h, 5 h, 6 h, 8 h, 10 h, or longer.

[0075] This method can further include providing a startup gas. The startup gas can be provided to the reactor after the reactor has reached a thermal steady state or a quasi-thermal steady state. The startup gas can be provided to initiate the pyrolysis reaction of the feedstock. The startup gas can be provided to initiate pyrolysis. The startup gas can contain at least about 50 mol%, 60 mol%, 70 mol%, 80 mol%, 90 mol%, or more hydrogen. In one example, the startup gas can contain pure or substantially pure hydrogen gas. In another example, the startup gas can contain about 80 mol% or more hydrogen. A non-hydrogen gas or a mixture thereof can be provided when the pyrolysis reaction is initiated.

[0076] Non-hydrogen gas can be provided to the reactor by a gas supply system. The non-hydrogen gas may be a plasma gas. The non-hydrogen gas may include nitrogen, helium, neon, krypton, argon, carbon monoxide, carbon dioxide, or any combination thereof. The non-hydrogen gas may be a pure gas. Alternatively, the non-hydrogen gas may include a mixture of gases. As shown in FIG. 1, the system may include a plurality of mass flow meters. When using a mixed non-hydrogen gas, one mass flow meter may be used for each different type of gas used to control the gas flow and mixing. The exemplary process of FIG. 1 may include a recycle loop configured to recycle and return the components of the exhaust gas to the reactor. In an industrial process, such a recycle loop can be configured to recycle the components of the exhaust gas and return them to the reactor, thereby increasing the efficiency of the raw materials and the conversion yield.

[0077] Non-hydrogen gas, separation gas, hydrogen, or any combination thereof may be, for example, about 0 standard cubic meters per hour (Nm 3 / h), 0.1 Nm³ / h, 0.2 Nm³ / h, 0.5 Nm³ / h, 1 Nm³ / h, 1.5 Nm³ / h, 2 Nm³ / h, 5 Nm³ / h, 10 Nm³ / h, 25 Nm³ / h, 50 Nm³ / h, 75 Nm³ / h, 100 Nm³ / h, 150 Nm³ / h, 200 Nm³ / h, 250 Nm³ / h, 300 Nm³ / h, 350 Nm³ / h, 400 Nm³ / h, 450 Nm³ / h, 500 Nm³ / h, 550 Nm³ / h, 600 Nm³ / h, 650 Nm³ / h, 700 Nm³ / h, 750 Nm³ / h, 800 Nm³ / h, 850 Nm³ / h, 900 Nm³ / h, 950 Nm³ / h, 1,000 Nm³ / h, 2,000 Nm³ / h, 3,000 Nm³ / h, 4,000 Nm³ / h, 5,000 Nm³ / h, 6,000 Nm³ / h, 7,000 Nm³ / h, 8,000 Nm³ / h, 9,000 Nm³ / h, 10,000 Nm³ / h, 12,000 Nm³ / h, 14,000 Nm³ / h, 16,000 Nm³ / h, 18,000 Nm³ / h, 20,000 Nm³ / h, 30,000 Nm³ / h, 40,000 Nm³ / h, 50,000 Nm³ / h, 60,000 Nm³ / h, 70,000 Nm³ / h, 80,000 Nm³ / h, 90,000 Nm 3 / h or 15,000 Nm 3It can be provided to the system at a rate of / hr or faster. Alternatively or additionally, the total of a given gas, or a subset or all of the process gases can be, for example, about 100,000 Nm3 / hr, 90,000 Nm3 / hr, 80,000 Nm3 / hr, 70,000 Nm3 / hr, 60,000 Nm3 / hr, 50,000 Nm3 / hr, 40,000 Nm3 / hr, 30,000 Nm3 / hr, 20,000 Nm3 / hr, 18,000 Nm3 / hr, 16,000 Nm3 / hr, 14,000 Nm3 / hr, 12,000 Nm3 / hr, 10,000 Nm3 / hr, 9,000 Nm3 / hr, 8,000 Nm3 / hr, 7,000 Nm3 / hr, 6,000 Nm3 / hr, 5,000 Nm3 / hr, 4,000 Nm3 / hr, 3,000 Nm3 / hr, 2,000 Nm3 / hr, 1,000 Nm3 / hr, 950 Nm3 / hr, 900 Nm3 / hr, 850 Nm3 / hr, 800 Nm3 / hr, 750 Nm3 / hr, 700 Nm3 / hr, 650 Nm3 / hr, 600 Nm3 / hr, 550 Nm3 / hr, 500 Nm3 / hr, 450 Nm3 / hr, 400 Nm3 / hr, 350 Nm3 / hr, 300 Nm3 / hr, 250 Nm3 / hr, 200 Nm3 / hr, 150 Nm3 / hr, 100 Nm3 / hr, 75 Nm3 / hr, 50 Nm3 / hr, 25 Nm3 / hr, 10 Nm3 / hr, 5 Nm3 / hr, 2 Nm 3 / hr, 1.5 Nm 3 / hr, 1 Nm 3 / hr, 0.5 Nm 3 / hr or 0.2 Nm 3It can be provided to the system (e.g., a reactor) at a rate of / hr or less. A non-hydrogen gas, a separation gas, hydrogen, or a mixture thereof can be provided to the system, for example, at a ratio of about 0, 0.0005, 0.001, 0.002, 0.005, 0.1, 0.2, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, 50, 75, or 90 moles or more per mole of feedstock, or at a ratio of about 100, 90, 75, 50, 45, 40, 35, 30, 25, 20, 15, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0.5, 0.2, 0.1, 0.005, 0.002, 0.001, or 0.0005 moles or less per mole of feedstock. About 100%, 75%, 50%, 40%, 30%, 20%, 10%, 5%, or 1% or less of the process gas(es) provided to the system can be heated with electrical energy. Alternatively or additionally, about 0%, 1%, 5%, 10%, 20%, 30%, 40%, 50%, or 75% or more of the process gas(es) provided to the system can be heated with electrical energy.

[0078] A non-hydrogen gas, a separated gas, hydrogen, or another gas (e.g., a raw material alone or in combination with at least one process gas) can be heated at a given pressure. The raw material (e.g., alone or in combination with at least one process gas) can react at a given pressure (also referred to herein as the "reaction pressure"). The heating and reaction can be implemented in a reactor at a given pressure (also referred to herein as the "reactor pressure"). The pressure can be, for example, about 0 bar, 0.5 bar, 1 bar, 1.1 bar, 1.2 bar, 1.3 bar, 1.4 bar, 1.5 bar, 1.6 bar, 1.7 bar, 1.8 bar, 1.9 bar, 2 bar, 2.1 bar, 2.2 bar, 2.3 bar, 2.4 bar, 2.5 bar, 2.6 bar, 2.7 bar, 2.8 bar, 2.9 bar, 3 bar, 3.1 bar, 3.2 bar, 3.3 bar, 3.4 bar, 3.5 bar, 3.6 bar, 3.7 bar, 3.8 bar, 3.9 bar, 4 bar, 4.5 bar, 5 bar, 6 bar, 7 bar, 8 bar, 9 bar, 10 bar, 11 bar, 12 bar, 13 bar, 14 bar, 15 bar, 16 bar, 17 bar, 18 bar, 19 bar, 20 bar, 21 bar, 22 bar, 23 bar, 24 bar, 25 bar, 26 bar, 27 bar, 28 bar, 29 bar, 30 bar, 35 bar, 40 bar, 45 bar, 50 bar, 55 bar, 60 bar, 65 bar, 70 bar, 75 bar, or higher.Alternatively or additionally, the pressure may be, for example, about 100 bar, 90 bar, 80 bar, 75 bar, 70 bar, 65 bar, 60 bar, 55 bar, 50 bar, 45 bar, 40 bar, 35 bar, 30 bar, 29 bar, 28 bar, 27 bar, 26 bar, 25 bar, 24 bar, 23 bar, 22 bar, 21 bar, 20 bar, 19 bar, 18 bar, 17 bar, 16 bar, 15 bar, 14 bar, 13 bar, 12 bar, 11 bar, 10 bar, 9 bar, 8 bar, 7 bar, 6 bar, 5 bar, 4 bar, 3.9 bar, 3.8 bar, 3.7 bar, 3.6 bar, 3.5 bar, 3.4 bar, 3.3 bar, 3.2 bar, 3.1 bar, 3 bar, 2.9 bar, 2.8 bar, 2.7 bar, 2.6 bar, 2.5 bar, 2.4 bar, 2.3 bar, 2.2 bar, 2.1 bar or less. The pressure may be higher than atmospheric pressure (above atmospheric pressure). The pressure may be from about 1.5 bar to about 25 bar. The pressure may be from about 1 bar to about 70 bar. The pressure may be from about 5 bar to about 25 bar. The pressure may be from about 10 bar to about 20 bar. The pressure may be from about 5 bar to about 15 bar. The pressure may be about 2 bar or higher. The pressure may be about 5 bar or higher. The pressure may be about 10 bar or higher. The raw material or process gas(es) can be provided to the reactor at a suitable pressure (e.g., at least about 0.01%, 0.05%, 0.1%, 0.5%, 1%, 2%, 5%, 10%, 15%, 20%, 25%, or 50% higher than the reactor pressure, and this pressure can vary depending on the injection method, such as the pressure through the injector being higher than through the inlet port). The raw material or process gas can be provided to the reactor, for example, at its respective delivery or storage (e.g., cylinder or container) pressure. The raw material or process gas may or may not be compressed (e.g., additionally) before being provided to the reactor.The incoming raw material can be provided at a pressure within the range defined by any two of the aforementioned pressure values. For example, the raw material can be provided at a pressure of about 30 to about 35 bar and can be metered down to a pressure of about 5 to about 15 bar. There may be a pressure drop across the reactor. For example, the inlet pressure of the reactor and the outlet pressure of the reactor may be different. The outlet pressure of the reactor can be a value selected from the aforementioned list that is lower than the inlet pressure selected from the aforementioned list. For example, a reactor having an inlet pressure of about 15 bar may have an outlet pressure of about 14 bar. In another example, the inlet pressure is about 4 bar and the outlet pressure can be about 2 bar. In another example, the inlet pressure is about 35 bar and the outlet pressure can be about 30 bar. The pressure drop across the reactor can assist in the movement of gas or carbon particles through the reactor.

[0079] One or more gases (e.g., the feedstock alone or in combination with at least one process gas (e.g., a non-hydrogen gas, hydrogen, etc.)) may be subjected to (e.g., exposed to) a reactor temperature of, for example, about 1,000 °C, 1,100 °C, 1,200 °C, 1,300 °C, 1,400 °C, 1,500 °C, 1,600 °C, 1,700 °C, 1,800 °C, 1,900 °C, 2,000 °C, 2,050 °C, 2,100 °C, 2,150 °C, 2,200 °C, 2,250 °C, 2,300 °C, 2,350 °C, 2,400 °C, 2,450 °C, 2,500 °C, 2,550 °C, 2,600 °C, 2,650 °C, 2,700 °C, 2,750 °C, 2,800 °C, 2,850 °C, 2,900 °C, 2,950 °C, 3,000 °C, 3,050 °C, 3,100 °C, 3,150 °C, 3,200 °C, 3,250 °C, 3,300 °C, 3,350 °C, 3,400 °C or 3,450 °C or higher. Alternatively or additionally, one or more gases (e.g., the feedstock alone or in combination with at least one process gas) may be heated to a reactor temperature of, for example, about 3,500 °C, 3,450 °C, 3,400 °C, 3,350 °C, 3,300 °C, 3,250 °C, 3,200 °C, 3,150 °C, 3,100 °C, 3,050 °C, 3,000 °C, 2,950 °C, 2,900 °C, 2,850 °C, 2,800 °C, 2,750 °C, 2,700 °C, 2,650 °C, 2,600 °C, 2,550 °C, 2,500 °C, 2,450 °C, 2,400 °C, 2,350 °C, 2,300 °C, 2,250 °C, 2,200 °C, 2,150 °C, 2,100 °C, 2,050 °C, 2,000 °C, 1,900 °C, 1,800 °C, 1,700 °C, 1,600 °C, 1,500 °C, 1,400 °C, 1,300 °C, 1,200 °C or 1,100 °C or less, or the feedstocks may be subjected to (e.g., exposed to) those temperatures. In one example, the non-hydrogen gas can be contacted with the hydrocarbon feedstock at a temperature of about 1900 °C or less. In another example, the non-hydrogen gas can be contacted with the hydrocarbon feedstock at a temperature of 1800 °C or less. In another example, the separation gas can be contacted with a further hydrocarbon feedstock at a temperature of about 1900 °C or less. In another example, the separation gas can be contacted with a further hydrocarbon feedstock at a temperature of about 1800 °C or less.By reducing the amount of hydrogen in the system, a yield similar to that of a higher reactor temperature using hydrogen plasma gas can be achieved at a lower reaction temperature.

[0080] By using a non-hydrogen gas as part or all of the plasma gas, thermal decomposition of hydrocarbon raw materials at lower temperatures becomes possible, thereby reducing wear of the apparatus (e.g., wear of electrodes and reactors), reducing energy input, reducing fouling, and enhancing control of carbon particles compared to a system that uses hydrogen alone or mainly hydrogen as the plasma gas. When the reaction temperature is lower, formation of particles with a lower Lc is also possible, changing and improving not only the elemental composition (e.g., the ratio of carbon to hydrogen), but also surface activity, the type of chemical functional groups bound to the surface, and other surface properties that can change the rubber reinforcement ability of the particles.

[0081] The conversion rate of hydrocarbon raw materials to carbon and hydrogen can be a factor in the economic viability of industrial hydrocarbon thermal decomposition processes. An increase in the conversion rate of the raw material can be achieved by increasing the reaction time, the reaction temperature, or both. When the reaction time is extended, a larger reactor will be used, thereby increasing the manufacturing cost of the reactor, decreasing the heat insulation efficiency of the reactor, and potentially increasing the operating cost. When the temperature rises, additional power will be used, thereby potentially increasing the manufacturing cost. By lowering the temperature and increasing the conversion rate by using a reduction in hydrogen concentration, the manufacturing costs of the carbon particles and hydrogen produced in the hydrocarbon thermal decomposition process can be reduced. The amount of hydrogen in the reactor can be reduced by removing the hydrogen produced from the reactor. The hydrogen produced can be removed along with the exhaust gas. In an example where recycled exhaust gas is used to reduce the hydrogen concentration in the reactor, hydrogen can be separated from higher molecular weight species. The separated hydrogen may not be returned to the reactor. Alternatively, a reduced amount of hydrogen may be returned to the reactor.

[0082] The non-hydrogen gas can be provided to the reactor as a pure or substantially pure non-hydrogen gas (e.g., any gas or gas mixture that does not contain hydrogen). Alternatively, the non-hydrogen gas can be mixed with hydrogen or injected in parallel with hydrogen. In one example, the non-hydrogen gas and the hydrogen gas are provided to the reactor in parallel. The ratio of the non-hydrogen gas to the hydrogen provided to the reactor can be at least about 2 to 1, at least about 4 to 1, at least about 6 to 1, at least about 8 to 1, at least about 10 to 1, at least about 15 to 1, at least about 20 to 1, at least about 25 to 1, at least about 30 to 1, at least about 40 to 1, or greater. In one example, the ratio of the non-hydrogen gas to the hydrogen provided to the reactor can be at least about 4 to 1. In another example, the ratio of the non-hydrogen gas to the hydrogen provided to the reactor can be at least about 10 to 1. The non-hydrogen gas and the hydrogen gas provided to the reactor can be provided from an external gas source, an effluent stream, or both. The effluent stream can be separated into hydrogen and high molecular weight species (e.g., non-hydrogen gas). The high molecular weight species, hydrogen, or both can be recycled or otherwise returned to the reactor. The amount of hydrogen in the return stream can be about 100 mole percent (mol%), 90 mol%, 80 mol%, 70 mol%, 60 mol%, 50 mol%, 40 mol%, 30 mol%, 25 mol%, 20 mol%, 15 mol%, 10 mol%, 5 mol%, or less. In one example, the return stream (e.g., the separated gas) can contain about 50 mol% or less hydrogen. In another example, the return stream (e.g., the separated gas) can contain about 25 mol% or less hydrogen. In another example, the return stream (e.g., the separated gas) can contain about 5 mol% or less hydrogen.

[0083] The hydrocarbon feedstock can be injected into the reactor either in parallel with the non-hydrogen gas or downstream of the non-hydrogen gas. In one example, the hydrocarbon feedstock is injected into the reactor downstream of the non-hydrogen gas. The hydrocarbon feedstock can be injected directly into the non-hydrogen gas. By injecting the hydrocarbon feedstock into the heated non-hydrogen gas, a pyrolysis process can be initiated to convert the hydrocarbon feedstock into solid carbon and hydrogen.

[0084] The characteristics of the carbon particles can be adjusted by modifying and regulating the molecular weight and composition of the gas (e.g., hydrocarbon feedstock, hydrogen, non-hydrogen gas) delivered to the pyrolysis reactor, or can be controlled by other means. Additionally, by controlling the molecular weight and composition of the delivered gas, the ability to produce a wider range of carbon black nanostructures is increased, and the product yield can be improved. The molecular weight or composition of the delivered gas can be controlled or otherwise adjusted by separating or purifying the exhaust gas and returning selected components to the reactor, with or without an externally supplied gas. The resulting delivered gas (e.g., plasma gas) can have an average molecular weight and composition. In one example, the system and method can include recycling at least a portion of the exhaust gas back to the reactor. The recycle stream can include at least one gas from the exhaust stream. Alternatively or additionally, the recycle stream can include a mixture of gases from the recycle stream. The gas returned from the recycle stream can mainly include high molecular weight species in order to increase the average molecular weight of the gas (e.g., plasma gas) delivered to the reactor. The high molecular weight species can include nitrogen, helium, neon, krypton, argon, carbon monoxide, carbon dioxide, water, methane, ethane, ethylene, or any combination thereof. The high molecular weight species may not include hydrogen. The molecular weight of the delivered gas can be controlled by blending or mixing high molecular weight species with hydrogen prior to delivery to the reactor. Recycling the exhaust gas back to the reactor can reduce production costs and increase the material use efficiency. Supplying external gas to the reactor enables direct control of the gas composition and can reduce costs and material use efficiency.

[0085] By increasing the average molecular weight of the plasma gas (e.g., the reaction gas), the hydrogen concentration in the gas phase within the reactor can be reduced. Reduction of the hydrogen concentration in the gas-phase hydrocarbon pyrolysis reaction can increase the surface area and structure of the carbon black particles produced, reduce fouling of the reactor, improve the conversion rate of the raw materials, and reduce wear of the graphite component. Examples of various process conditions by which the effects listed above can be achieved by reducing the hydrogen concentration of the reaction gas are described.

[0086] The average molecular weight of the gas delivered (e.g., the gas used to generate the plasma or plasma gas) can be at least about 1 kilogram per kilomole (kg / kmol), 1.5 kg / kmol, 2 kg / kmol, 3 kg / kmol, 4 kg / kmol, 5 kg / kmol, 10 kg / kmol, 15 kg / kmol, 20 kg / kmol, 25 kg / kmol, 30 kg / kmol, 40 kg / kmol, 50 kg / kmol, 60 kg / kmol, 70 kg / kmol, 80 kg / kmol, 90 kg / kmol, or more per kilomole. The average molecular weight of the gas delivered is It may be about 90 kg / kmol, 80 kg / kmol, 70 kg / kmol, 60 kg / kmol, 50 kg / kmol, 40 kg / kmol, 30 kg / kmol, 25 kg / kmol, 20 kg / kmol, 15 kg / kmol, 10 kg / kmol, 5 kg / kmol, 4 kg / kmol, 3 kg / kmol, 2 kg / kmol, 1.5 kg / kmol, 1 kg / kmol, or less. The average molecular weight of the gas to be delivered is about 1 kg / kmol to 1.5 kg / kmol, 1 kg / kmol to 2 kg / kmol, 1 kg / kmol to 3 kg / kmol, 1 kg / kmol to 4 kg / kmol, 1 kg / kmol to 5 kg / kmol, 1 kg / kmol to 10 kg / kmol, 1 kg / kmol to 15 kg / kmol, 1 kg / kmol to 20 kg / kmol, 1 kg / kmol to 25 kg / kmol, 1 kg / kmol to 30 kg / kmol, 1 kg / kmol to 40 kg / kmol, 1 kg / kmol to 50 kg / kmol, 1 kg / kmol to 60 kg / kmol, 1 kg / kmol to 70 kg / kmol, 1 kg / kmol to 80 kg / kmol, 1 kg / kmol to 90 kg / kmol, 1.5 kg / kmol to 2 kg / kmol, 1.5 kg / kmol to 3 kg / kmol, 1.5 kg / kmol to 4 kg / kmol, 1.5 kg / kmol to 5 kg / kmol, 1.5 kg / kmol to 10 kg / kmol, 1.5 kg / kmol to 15 kg / kmol, 1.5 kg / kmol to 20 kg / kmol, 1.5 kg / kmol to 25 kg / kmol, 1.5 kg / kmol to 30 kg / kmol, 1.5 kg / kmol to 40 kg / kmol, 1.5 kg / kmol to 50 kg / kmol, 1.5 kg / kmol to 60 kg / kmol, 1.5 kg / kmol to 70 kg / kmol, 1.5 kg / kmol to 80 kg / kmol, 1.5 kg / kmol to 90 kg / kmol, 2 kg / kmol to 3 kg / kmol, 2 kg / kmol to 4 kg / kmol, 2 kg / kmol to 5 kg / kmol, 2 kg / kmol to 10 kg / kmol, 2 kg / kmol to 15 kg / kmol, 2 kg / kmol to 20 kg / kmol, 2 kg / kmol to 25 kg / kmol, 2 kg / kmol to 30 kg / kmol, 2 kg / kmol to 40 kg / kmol, 2 kg / kmol to 50 kg / kmol,2 kg / kmol to 60 kg / kmol, 2 kg / kmol to 70 kg / kmol, 2 kg / kmol to 80 kg / kmol, 2 kg / kmol to 90 kg / kmol, 3 kg / kmol to 4 kg / kmol, 3 kg / kmol to 5 kg / kmol, 3 kg / kmol to 10 kg / kmol, 3 kg / kmol to 15 kg / kmol, 3 kg / kmol to 20 kg / kmol, 3 kg / kmol to 25 kg / kmol, 3 kg / kmol to 30 kg / kmol, 3 kg / kmol to 40 kg / kmol, 3 kg / kmol to 50 kg / kmol, 3 kg / kmol to 60 kg / kmol, 3 kg / kmol to 70 kg / kmol, 3 kg / kmol to 80 kg / kmol, 3 kg / kmol to 90 kg / kmol, 4 kg / kmol to 5 kg / kmol, 4 kg / kmol to 10 kg / kmol, 4 kg / kmol to 15 kg / kmol, 4 kg / kmol to 20 kg / kmol, 4 kg / kmol to 25 kg / kmol, 4 kg / kmol to 30 kg / kmol, 4 kg / kmol to 40 kg / kmol, 4 kg / kmol to 50 kg / kmol, 4 kg / kmol to 60 kg / kmol, 4 kg / kmol to 70 kg / kmol, 4 kg / kmol to 80 kg / kmol, 4 kg / kmol to 90 kg / kmol, 5 kg / kmol to 10 kg / kmol, 5 kg / kmol to 15 kg / kmol, 5 kg / kmol to 20 kg / kmol, 5 kg / kmol to 25 kg / kmol, 5 kg / kmol to 30 kg / kmol, 5 kg / kmol to 40 kg / kmol, 5 kg / kmol to 50 kg / kmol, 5 kg / kmol to 60 kg / kmol, 5 kg / kmol to 70 kg / kmol, 5 kg / kmol to 80 kg / kmol, 5 kg / kmol to 90 kg / kmol, 10 kg / kmol to 15 kg / kmol, 10 kg / kmol to 20 kg / kmol, 10 kg / kmol to 25 kg / kmol, 10 kg / kmol to 30 kg / kmol, 10 kg / kmol to 40 kg / kmol, 10 kg / kmol to 50 kg / kmol, 10 kg / kmol to 60 kg / kmol, 10 kg / kmol to 70 kg / kmol, 10 kg / kmol to 80 kg / kmol, 10 kg / kmol to 90 kg / kmol, 20 kg / kmol to 25 kg / kmol, 20 kg / kmol to 30 kg / kmol,It can be 20 kg / kmol to 40 kg / kmol, 20 kg / kmol to 50 kg / kmol, 20 kg / kmol to 60 kg / kmol, 20 kg / kmol to 70 kg / kmol, 20 kg / kmol to 80 kg / kmol, 20 kg / kmol to 90 kg / kmol, 25 kg / kmol to 30 kg / kmol, 25 kg / kmol to 40 kg / kmol, 25 kg / kmol to 50 kg / kmol, 25 kg / kmol to 60 kg / kmol, 25 kg / kmol to 70 kg / kmol, 25 kg / kmol to 80 kg / kmol, 25 kg / kmol to 90 kg / kmol, 30 kg / kmol to 40 kg / kmol, 30 kg / kmol to 50 kg / kmol, 30 kg / kmol to 60 kg / kmol, 30 kg / kmol to 70 kg / kmol, 30 kg / kmol to 80 kg / kmol, 30 kg / kmol to 90 kg / kmol, 40 kg / kmol to 50 kg / kmol, 40 kg / kmol to 60 kg / kmol, 40 kg / kmol to 70 kg / kmol, 40 kg / kmol to 80 kg / kmol, 40 kg / kmol to 90 kg / kmol, 50 kg / kmol to 60 kg / kmol, 50 kg / kmol to 70 kg / kmol, 50 kg / kmol to 80 kg / kmol, 50 kg / kmol to 90 kg / kmol, 60 kg / kmol to 70 kg / kmol, 60 kg / kmol to 80 kg / kmol, 60 kg / kmol to 90 kg / kmol, 70 kg / kmol to 80 kg / kmol, 70 kg / kmol to 90 kg / kmol, or 80 kg / kmol to 90 kg / kmol.

[0087] The exhaust gas may be returned directly to the reactor, or upstream of the reactor in the plasma chamber, upstream or downstream of the electrode body, or any combination thereof. Alternatively or additionally, the exhaust gas may be separated into one or more gas streams. One of the one or more gas streams can contain non-hydrogen species (e.g., high molecular weight species), and another of the one or more gas streams can contain hydrogen. The components of the exhaust gas can be separated as described elsewhere in this specification. The gas composition of the recycle stream can include gas derived from the exhaust stream, gas supplied from the outside, or any combination thereof. In one example, the exhaust gas is separated into hydrogen and non-hydrogen species. After separation, the hydrogen or non-hydrogen gas can be further processed (e.g., compressed, heated, cooled, purified, etc.) to produce a derived gas of the separated gas. The recycle stream can include the separated gas, one or more derived gases, or any combination thereof. The recycle stream can include, but is not limited to, hydrogen, nitrogen, helium, neon, krypton, argon, carbon monoxide, carbon dioxide, water, methane, ethane, ethylene, hydrogen cyanide, or any combination thereof.

[0088] The recycle stream may or may not be mixed with an external gas before being provided to the reactor. In one example, the recycle stream is not mixed with an external gas before being provided to the reactor. In another example, the recycle stream is mixed with an external gas before being provided to the reactor. The recycle stream may be mixed with an external gas stream, and thus the combined stream contains at least about 5 mol%, 10 mol%, 15 mol%, 20 mol%, 25 mol%, 30 mol%, 40 mol%, 50 mol%, 60 mol%, 70 mol%, 80 mol%, 90 mol%, or more gas from the recycle stream. The recycle stream may be mixed with an external gas stream, and thus the combined stream contains about 90 mol%, 80 mol%, 70 mol%, 60 mol%, 50 mol%, 40 mol%, 30 mol%, 25 mol%, 20 mol%, 15 mol%, 10 mol%, 5 mol%, or less gas from the recycle stream. The external gas can be any of the gases described elsewhere in this specification, such as nitrogen, helium, neon, krypton, argon, carbon monoxide, carbon dioxide, or any combination thereof.

[0089] Figures 2 - 4 show examples of plasma pyrolysis processes that can be used to produce carbon particles and hydrogen. By modulating the molecular weight and composition of the preheated reaction gas (e.g., plasma gas) streams (115, 215, 315), the morphology and yield of carbon nanostructures within the plasma reactors (103, 203, 303) can be affected. By controlling both the gas composition and molecular weight of this stream, the ability to create a wider range of carbon nanostructures is expanded, the yield is increased, and the cost of the feedstock (101, 201, 301) can be reduced.

[0090] The reaction products from the plasma pyrolysis reactors (103, 203, 303) are cooled in the heat exchange systems (104, 204, 304), exchanged with each other to generate steam (119, 219, 319), and can provide preheating to the reaction gas (e.g., plasma gas) streams (115, 215, 315). The heat exchange system can be composed of a series of at least one or more gas-to-gas heat exchangers, a boiler feed water preheater, a saturated steam boiler, and a superheater. The solid-phase reaction products can be separated from the gas-phase products by the main filters (105, 205, 305). The solid carbon products can be densified by the pelletizers (116, 216, 316) and then dried by the dryers (117, 217, 317) before exiting the process. The dryer may be a rotary dryer or a fluidized bed dryer. In addition to the pelletizers and dryers, there may be a milling and grinding device for homogenizing the size of the carbon particles.

[0091] The gaseous reaction products exiting the filters (105, 205, 305) can be compressed from near atmospheric pressure to at least about 10 bar absolute (bara) after being cooled in the heat exchangers (106, 206, 306). In this heat exchanger, steam or preheated boiler feed water (120, 220, 320) can be generated. The cooled reaction gas can then have its pressure increased to at least 10 bara by the compressors (107, 207, 307). At the elevated pressure, impurities in the gas stream may liquefy or pose problems to the purification devices (110, 210, 310), and thus, an impurity removal system (108, 208, 308) can be used. The impurity removal system may be, but is not limited to, a cryogenic separator, a hydrolysis reactor and cooler, an adsorption / stripping column, a methanator, or any combination thereof. Liquid impurities can be removed and collected as a product or disposed of in a flare or thermal oxidation unit.

[0092] When all impurities unacceptable to the purification unit (110) can be removed, the remaining gas is separated to obtain a hydrogen stream (111, 113) with a purity exceeding 99.9% and a stream (112, 114) with an increased molecular weight. The gas purification unit may be, but is not limited to, a pressure swing adsorption unit, and / or a membrane separation unit, and / or an absorption / stripper separation unit, and / or a cryogenic separation unit, or any combination thereof.

[0093] Figure 2 schematically shows an example of a process in which a reaction gas stream with a controlled molecular weight and composition is supplied to a pyrolysis reactor by purifying the gaseous product from the plasma pyrolysis reactor in the absence of an external non-feed gas source. This process may include providing a hydrocarbon feedstock (101) and a preheated reaction (e.g., plasma) gas (115). The hydrocarbon feedstock (101) and the preheated reaction (e.g., plasma) gas (115) can be pyrolyzed in a plasma pyrolysis reactor (103) supplied by electricity (102). The preheated reaction gas (115) from the process heat exchanger (104) can be supplied by purifying the gaseous product exiting the reaction vessel (103). The molecular weight composition of the reaction gas can be controlled by modulating the flow of the recycle stream (114) with an increased molecular weight and the flow of the hydrogen recycle blend (113) with a purity exceeding 99.9%. The excess 99.9% hydrogen (111) can exit the system as a product for downstream handling applications, and any excess recycle gas with an increased molecular weight can be a high molecular weight molecule. The high molecular weight species can be recycled back to the reactor to form solid carbon particles. In one example, the high molecular weight species that are not recycled back to the reactor can be disposed of in a flare or a thermal oxidizer.

[0094] Figure 3 schematically shows an example of a process in which a reaction gas stream of controlled molecular weight and composition is partially supplied to a pyrolysis reactor by purifying gaseous products from the plasma pyrolysis reactor and gaseous products from a gas partially supplied externally. In this example, a portion of the preheated reaction gas (215) can be supplied by a gas purification system (210) via a recycle stream (214) with increased molecular weight having a hydrogen recycle ability by a hydrogen recycle stream (213) of more than 99.9%, and a portion of the preheated reaction gas (215) can be supplied by an external gas (216).

[0095] Figure 4 schematically shows an example of a process in which a reaction gas stream (e.g., a plasma gas stream) of controlled molecular weight and composition is supplied to a pyrolysis reactor by an external gas stream. In this example, the preheated reaction gas (e.g., a plasma gas) (315) is supplied by an external source (316) having the ability to modulate the molecular weight and composition via a hydrogen recycle stream (313) of more than 99.9%.

[0096] The gas supply system may include valves (e.g., electronic or mechanical), pressure regulators, mass flow controllers, or any combination thereof. The valves, regulators, and flow rate controllers can be centrally managed, for example, by one or more computer controllers. The gas supply system may be configured to control or be able to control the flow of gas (e.g., plasma gas) or hydrocarbon feedstock to the reactor.

[0097] The flow rates of the plasma gas (e.g., non-hydrogen gas, hydrogen gas, or both) and the hydrocarbon feedstock can be controlled to maintain a given dilution ratio or modulated in other ways. The dilution ratio (DR) can be calculated as shown in Equation 2. [Number] The diluent gas may include a non-hydrogen gas, hydrogen, or other gas that does not contain carbon. The dilution ratio may be about 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, or less. The dilution ratio may be about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or higher.

[0098] The hydrocarbon feedstock (e.g., methane) can be converted to carbon particles and hydrogen in the presence of plasma. The conversion of the hydrocarbon feedstock and the total solid yield can be computer-calculated and estimated from the measured flow and gas analysis measurement means as described elsewhere in this specification. In one example, the hydrocarbon feedstock can include methane, and the conversion rate of methane can be calculated as shown in Equation 3.

Number

Number

Number

[0099] The reaction equilibrium of methane pyrolysis can be modulated by the relative concentration of hydrogen in the reactor. For example, according to Le Chatelier's principle, by reducing the hydrogen concentration in the reactor, the reaction can shift towards the product side, resulting in an increase in methane conversion rate and product yield. The hydrogen concentration can be reduced by using a non-hydrogen diluent gas (e.g., for generating plasma) or by removing the product hydrogen from the system. By shifting the reaction towards the product generation side by lowering the hydrogen concentration, the reactor can be operated at a lower temperature without reducing the product yield or methane conversion rate. Additionally, the generated carbon particles can have a surface area similar to or larger than that of the particles generated in a similar reactor system using a higher hydrogen concentration and a higher temperature. Recycling the separated gas and providing additional hydrocarbon feedstock to the reactor can increase the conversion efficiency of the hydrocarbon feedstock. For example, by recycling the separated gas and providing additional hydrocarbon feedstock, the conversion efficiency of the hydrocarbon feedstock can increase to about 98% or higher.

[0100] This process can have a feedstock conversion rate of about 50%, 60%, 70%, 80%, 85%, 90%, 95%, 98%, or higher. In one example, the feedstock conversion rate is about 80% or higher. In another example, the feedstock conversion rate is about 90% or higher. In another example, the feedstock conversion rate is about 95% or higher. This process can have a total solid yield of about 50%, 60%, 70%, 80%, 85%, 90%, 95%, 98%, or higher. In one example, the total solid yield is about 80% or higher. In another example, the total solid yield is about 90% or higher. In another example, the total solid yield is about 95% or higher. This process can have a hydrogen yield of about 50%, 60%, 70%, 80%, 85%, 90%, 95%, 98%, or higher. In one example, the hydrogen yield is about 80% or higher. In another example, the hydrogen yield is about 90% or higher. In another example, the hydrogen yield is about 95% or higher.

[0101] The influence of hydrogen concentration can be promoted by, or otherwise affected by, particle nucleation and formation, chemical equilibrium kinetics, thermochemical gas attack, or combinations thereof. The hydrogen concentration can change the quality, conversion, and fouling of the particles based on the effect of hydrogen concentration on the chemical kinetics of the mixture and various reaction rates. The process of forming solid carbon from a pure hydrocarbon feedstock can include several reversible reactions that occur continuously. Using a methane feedstock at temperatures of about 1500 °C to 2100 °C, methane can lose hydrogen and add carbon to form acetylene. Acetylene may form aromatic rings, which may grow into larger polycyclic aromatic hydrocarbons (PAHs) and may grow on the large plane of the aromatic ring. The large planes of the aromatic rings may combine to form solid carbon nuclei. Throughout this process, as the intermediate products approach the formation of pure carbon, hydrocarbon molecules can release hydrogen in many reactions. Since these reactions can be reversible, the lower the hydrogen content of the gas mixture, the more rapidly dehydrogenation can occur as a result.

[0102] When hydrocarbon gas contacts the walls of the reactor, harder carbon deposits (e.g., fouling) are more likely to form than when solid carbon particles contact the walls. The more rapidly the feedstock is converted from hydrocarbon gas to solid particles, the less contact there is between the hydrocarbon gas and the walls, and as a result, fouling can be kept to a minimum.

[0103] A decrease in hydrogen content can change the surface area and structure of the resulting carbon, due to changes in the rate of particle nucleation and growth. The surface area and structure can be representative of the individual "primary" particles formed during the formation of carbon black. In some cases, a low percentage of hydrogen can increase the rate at which the hydrocarbon feedstock is converted to solid carbon. As this rate increases, the rate of formation of new particles can also increase. As the formation of new particles speeds up, more carbon can be directed towards the formation of new particles rather than being added to existing particles. As a result, as hydrogen decreases, more new particles can be formed. As the number of particles increases, the surface area and structure can increase. The surface area and structure can be as described elsewhere in this specification. The carbon particles may have an agglomeration structure of at least about 100 milliliters per 100 grams of carbon black (mL / 100g) as measured by dibutyl phthalate (DBP) absorption. DBP absorption can be controlled or adjusted by adding an additive during the pyrolysis of the hydrocarbon feedstock. The additive may be an ionic compound such as an alkali metal salt, for example. Alkali metal salts can include acetates, adipates, ascorbates, benzoates, bicarbonates, carbonates, citrates, dehydroacetates, erythorbates, ethyl para-hydroxybenzoates, formates, fumarates, gluconates, hydrogen acetates, hydroxides, lactates, malates, methyl para-hydroxybenzoates, orthophenylphenol, propionates, propyl para-hydroxybenzoates, sorbates, succinates, or tartrates of sodium, potassium, rubidium, cesium, or any combination thereof, but are not limited thereto. In one example, the additive may be potassium. Alternatively, the agglomeration structure can be controlled or adjusted in the absence of an additive (e.g., in the absence of an alkali metal salt such as potassium). The carbon black produced using the methods described herein may be natural carbon black.Natural carbon black can be carbon black produced without chemical additives used to control structure. This method can include providing a mixed non-hydrogen and hydrogen plasma gas. For example, the plasma gas can include about 50 mol% or more of non-hydrogen gas. The carbon particles produced can have a DBP structure of about 100 mL / carbon particle 100 g or more. The carbon particles can be natural carbon particles. Natural carbon particles produced using a mixed plasma gas containing about 50 mol% or more of non-hydrogen gas can have at least about 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or more DBP structure than natural carbon particles produced using a mixed plasma gas containing about 80 mol% or more of hydrogen. In one example, natural carbon particles produced using a mixed plasma gas containing about 50 mol% or more of non-hydrogen gas can have at least about 30% more DBP structure than natural carbon particles produced using a mixed plasma gas containing about 80 mol% or more of hydrogen.

[0104] The plasma source can be a three-phase plasma torch. The plasma torch can be powered by a multi-stage conversion power supply with controlled current. The multi-stage power supply may be configured to provide up to about 250 kilovolt-amperes (kVA) at 50 Hertz (Hz), or can provide it. The power supply can provide from about 0 kilowatts (kW) to about 50 kW at a frequency from about 0 Hertz (Hz) to about 1 megahertz (MHz). A thermodynamically equilibrium arc discharge may occur and alternate between the electrode tips. The plasma torch can include at least 1, 2, 3, 4, 5, 6, or more electrodes. In one example, the plasma torch includes three electrodes and the plasma occurs alternately between the three electrode tips. The electrode(s) can be formed from any conductive material capable of generating plasma and withstanding a temperature of 3000 °C or higher. The electrodes may be formed from the same material, or different electrodes may be formed from different materials. The electrode(s) can include graphite, carbon-carbon composite, reticulated vitreous carbon (RVC), vitreous carbon, amorphous carbon, pyrolytic carbon, or any combination thereof. In one example, the electrode can be formed from or include graphite.

[0105] The electrode can be a consumable and can be gradually consumed by erosion during the pyrolysis process. By reducing the hydrogen content in the reaction gas (also called plasma gas, dilution gas, or carrier gas for example), the consumption of reactor components such as graphite reactor components (for example, electrodes (plurals possible), liners, etc.) can be reduced. Since hydrogen gas may react with carbon on the surface (for example, graphite surface) to produce gas-phase hydrocarbons, the consumption of reactor components may occur in a high-temperature, high-hydrogen environment, but this gas-phase hydrocarbon can be removed from the process as an exhaust gas. The consumption of carbon on the surface of the reactor components deteriorates the reactor structure, and as a result, the cost of certain components that may be consumed during operation may increase. By removing hydrogen from the reaction gas, the attack of hydrogen on the reactor surface can be prevented or reduced, thereby extending the life of the components and reducing the production cost. The erosion of the electrode can be reduced by using electrodes (plurals possible) formed from a highly heat-resistant material such as graphite. Alternatively or additionally, the erosion of the electrode can be reduced by lowering the reaction temperature or reducing the hydrogen concentration in the reactor. The electrode (plurals possible) can be consumed at a rate of about 5 kilograms of carbon per megawatt-hour (kg carbon / MW-hour), 4 kg carbon / MW-hour, 3 kg carbon / MW-hour, 2 kg carbon / MW-hour, 1.5 kg carbon / MW-hour, 1 kg carbon / MW-hour, 0.8 kg carbon / MW-hour, 0.6 kg carbon / MW-hour, 0.4 kg carbon / MW-hour, 0.2 kg carbon / MW-hour, 0.1 kg carbon / MW-hour, or less. In one example, the electrode (plurals possible) is consumed at a rate of about 0.6 kg carbon / MW-hour or less.

[0106] Erosion or wear of the electrode(s) can change the quality or stability of the generated plasma. To maintain a consistent plasma, the electrode(s) can be fixed in place by an electrode holder. The electrode holder may be configured to control the position of the electrode(s) within the discharge zone or can be controlled in other ways. Due to electrode wear, the dimensions of the electrode(s) may change. When the dimensions of the electrode(s) change, the holder can adjust the position of the electrode(s) in real time (e.g., simultaneously with the pyrolysis reaction). The rate of repositioning of the electrode may be equal to or substantially equal to the erosion rate of the electrode(s).

[0107] Reactor fouling can also increase the cost and complexity of producing solid carbon and hydrogen. By reducing the hydrogen concentration within the reactor, reactor fouling can be reduced. Reactor fouling can be due to the deposition of solid carbon from the gas-phase reaction on a part of the reactor. Fouling can cause a change in the reactor shape, block injection ports, change the gas flow within the reactor, or a combination thereof. By reducing the hydrogen content of the reaction gas (also called plasma gas, dilution gas, or carrier gas for example), the conversion of hydrocarbons to products can be accelerated. By removing or reducing the hydrocarbon gas that causes fouling, the amount of fouling generated can be reduced. When fouling is reduced, the manufacturing cost can also be reduced by operating the reactor longer without stopping for maintenance. On a molar basis, about 20%, 15%, 10%, 8%, 6%, 5%, 4%, 3%, 2%, 1%, or less of the input carbon can be converted to fouling. In one example, about 10% or less of the input carbon can be converted to fouling. In another example, about 4% or less of the input carbon can be converted to fouling.

[0108] The system may further include a quench system. The quench system may use hydrogen or a non-hydrogen gas to cool the generated carbon particles, the exhaust gas, or both. The quench system may be configured to cool the lower region of the reactor such that the carbon particles, the exhaust gas, or the particles are discharged from the reactor at a temperature low enough to be compatible with the filter system(s), or may be cooled in other ways. The quench gas may be hydrogen, nitrogen, argon, krypton, neon, carbon monoxide, carbon dioxide, or any combination thereof. Since the recycle stream may contain residual feedstock and high molecular weight carbonaceous components, the quench may also include the feedstock. In one example, unpurified hydrogen (e.g., hydrocarbon contaminated hydrogen) may be used as the quench. The quench may be a mixed hydrogen gas, which may contain about 0.1 mol% to 4% hydrocarbons. In one example, the quench gas contains hydrogen, argon, nitrogen, or any combination thereof. In one example, the quench gas contains hydrogen or is hydrogen. The quench gas (e.g., hydrogen or hydrogen mixture) is about 50 Newton meter cubic per hour (Nm 3 / h) to 100 Nm 3 / h, 50 Nm 3 / hr to 150 Nm 3 / hr, 50 Nm 3 / hr to 200 Nm 3 / hr, 50 Nm 3 / hr to 250 Nm 3 / hr, 50 Nm 3 / hr to 300 Nm 3 / hr, 50 Nm 3 / hr to 400 Nm 3 / hr, 50 Nm 3 / hr to 500 Nm 3 / hr, 100 Nm 3 / hr to 150 Nm 3 / hr, 100 Nm 3 / hr to 200 Nm 3 / hr, 100 Nm 3 / hr to 250 Nm 3 / hr, 100 Nm 3 / hr to 300 Nm 3 / hr, 100 Nm 3 / hr to 400 Nm 3 / hr, 100 Nm 3 / hr to 500 Nm 3 / hr, 150 Nm 3 / hr to 200 Nm 3 / hr, 150 Nm 3 / hr to 250 Nm 3 / hr, 150 Nm 3 / hr to 300 Nm 3 / hr, 150 Nm 3 / hr to 400 Nm 3 / hr, 150 Nm 3 / hr to 500 Nm 3 / hr, 200 Nm 3 / hr to 250 Nm 3 / hr, 200 Nm 3 / hr to 300 Nm 3 / hr, 200 Nm 3 / hr to 400 Nm 3 / hr, 200 Nm 3 / hr to 500 Nm 3 / hr, 250 Nm 3 / hr to 300 Nm 3 / hr, 250 Nm 3 / hr to 400 Nm 3 / hr, 250 Nm 3 / hr to 500 Nm 3 / hr, 300 Nm 3 / hr to 400 Nm 3 / hr, 300 Nm 3 / hr to 500 Nm 3 / hr, or 400 Nm 3 / hr to 500 Nm 3 It can be injected into the quench system at a flow rate of / hr. In one example, the quench gas is about 100 Nm 3 / hour to 200 Nm 3 / hour and can be provided to the quench system. In another example, the quench gas may be nitrogen, and nitrogen can be provided to the quench system at a flow rate of about 100 Nm 3 / hour to 200 Nm 3 / hour and can be provided to the quench system.

[0109] The reactor may be equipped with various diagnostic and analytical devices, such as, but not limited to, temperature probes, pressure probes, optical pyrometry, electrical probes, high-speed cameras, emission spectroscopy, or any combination thereof. The reactor may be configured to allow optical access to the interior volume of the reactor or may further include a window that allows it. Non-limiting examples of window materials include quartz, borosilicate, fused silica, or sapphire.

[0110] The components of the exhaust gas (e.g., non-hydrogen gas, hydrogen, gaseous by-products, etc.) can be separated using one or more of pressure swing adsorption (PSA), membrane separation, cryogenic separation, absorption column, stripping column, gas compressor, or any combination thereof.

[0111] The system may further include various separation assemblies. The solid carbonaceous material can be separated from the gaseous components. The separation unit or the hydrogen / exhaust gas removal unit may include, but is not limited to, a pressure swing adsorption device, a cryogenic separation device, a molecular sieve, or any combination thereof. The pressure swing adsorption (PSA) device can be configured to separate or purify components from a gas stream (e.g., components from the gas stream produced by the reactor as described elsewhere herein). The PSA device may include selectively passing components of the mixture using the adsorption and characteristics (e.g., molecular size, dipole moment, etc.) of different components of the gas mixture. For example, the PSA device can be used to separate hydrogen from the reactor gas mixture. In this example, the PSA device can separate hydrogen using its small size by passing the gas mixture over a porous bed (e.g., a bed of porous zeolite) that acts as a sieve. In this example, hydrogen can pass through the sieve while larger species in the gas mixture are filtered by being trapped in the sieve. In this example, the sieve can be saturated with the larger gas and then regenerated by removing the bed and removing the larger gas species. Multiple PSA devices can be used in parallel or in series. For example, multiple PSA devices can be set up in parallel to allow for continuous processing of the gas while a subset of the PSA devices is being regenerated. The PSA device can operate at a pressure of at least about 1, 5, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 gauge pressure (barg) or higher. The PSA device can operate at a pressure of up to about 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 5 gauge pressure (barg) or less. The PSA device can operate at a pressure within a range defined by any two of the aforementioned values.For example, the PSA device can operate at a pressure between about 13 to about 24 barg. The PSA device can operate at a gas inlet temperature of at least about -50, -45, -40, -35, -30, -25, -20, -15, -10, -5, 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70 degrees Celsius or higher. The PSA device can operate at a gas inlet temperature of at most about 70, 65, 60, 55, 50, 45, 40, 35, 30, 25, 20, 15, 10, 5, 0, -5, -10, -15, -20, -25, -30, -45, -50 degrees Celsius or lower. For example, the PSA can operate at a temperature higher than the temperature at which the components of the gas mixture condense.

[0112] The system may further include a cryogenic separation device. The cryogenic separation device may be configured to separate components (e.g., different gases of a gas mixture) using cryogenic temperatures (e.g., below ambient temperature). For example, the cryogenic separation device can be configured to cool the mixture until all components of the mixture condense, and then utilize an increase in temperature or pressure to remove (e.g., boil off) components for separation. Cryogenic separation can provide components (e.g., hydrogen) of a high-purity gas mixture.

[0113] The system may further include a filter assembly. The method may further include using the filter assembly to separate carbon particles from the non-hydrogen gas. The filter assembly may include or be integrated with a packaging device configured to sample the generated carbon particles. Sampling can be manual sampling or automatic sampling. In one example, the sampling may be automatic.

[0114] After being separated from the gas mixture, the hydrogen from the reactor can be further purified. In some cases, the hydrogen is of sufficient purity at the time it is removed from the gas mixture (e.g., no further purification may be necessary). In some cases, the hydrogen is purified by a PSA device, a cryogenic separation device, a molecular sieve, etc., or any combination thereof. In some cases, the hydrogen can be pressurized at the time it is removed from the gas mixture. For example, the hydrogen can be pressurized before being fed to the purification device. After purification, the hydrogen may be at least about 50, 60, 70, 80, 85, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 99.9, 99.99, 99.999, 99.9999, 99.99999 percent (e.g., mole, weight, or volume percent) or higher purity. After purification, the hydrogen may be at most about 99.99999, 99.9999, 99.999, 99.99, 99.9, 99, 98, 97, 96, 95, 94, 93, 92, 91, 90, 85, 80, 70, 60, 50 percent (e.g., mole, weight, or volume percent) or less purity. The gases removed from the hydrogen during purification can include hydrocarbons (e.g., methane, ethane, ethylene, acetylene, propene, benzene, toluene, naphthalene, anthracene, etc.), hydrogen, nitrogen, hydrogen cyanide, carbon monoxide, noble gases (e.g., argon, neon, krypton, etc.), etc., or any combination thereof. The gases removed from the hydrogen can constitute at least about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25 mole percent or more of the gas mixture. The gases removed from the hydrogen can constitute at most about 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 mole percent or less of the gas mixture.

[0115] The system or process may further include a high-pressure degassing device. The carbon particles (e.g., carbon black, etc.) described elsewhere in this specification generated by the processes described elsewhere in this specification can be directed towards the upper part of the degassing device as shown. The carbon particles first contact a filter in front of the high-pressure degassing device and can fall from the filter to the upper part of the device as shown. The carbon particles can contact a rotary valve. The rotary valve can be configured to meter the carbon particles by dropping the carbon particles through an open airlock valve into the degassing vessel. The presence of the rotary valve can prevent too many carbon particles from entering the degassing vessel at one time. The rotary valve can also provide a certain degree of backflow prevention function to prevent gas from flowing back from the degassing vessel. The carbon particles can be collected in the degassing vessel until a predetermined amount of carbon particles is reached. Thereafter, the rotary valve and the airlock valve can be closed, and the vent valve can be opened. The opening of the vent valve can release the gas at the pressure inside the degassing vessel (e.g., when the carbon particles are introduced into the vessel under pressure) and bring the degassing vessel to atmospheric pressure. Next, the vent valve can be closed and the inert purge valve can be opened to allow a flow of inert gas (e.g., the inert gas described elsewhere in this specification). The inert gas can be configured to replace or dilute the gas associated with the carbon particles (e.g., adsorbed). For example, a combustible or explosive gas (e.g., hydrogen, hydrocarbon, etc.) can be adsorbed on the surface of the carbon particles, and the inert gas can replace the combustible or explosive gas. After the introduction of the inert gas, the purge valve can be closed and the vent valve can be opened to vent the mixture of the inert gas and the gas associated with the carbon particles. The purge with the inert gas can be repeated until the carbon particles are considered to be inert (e.g., until the gas inside the carbon particles is present at a safe level). Next, the carbon particles can be removed from the degassing vessel through the airlock valve. For example, the airlock valve can be opened and the carbon particles can fall from the degassing vessel by gravity.Next, the airlock valve can be closed and this process can be repeated for another batch of carbon particles.

[0116] By using a high-pressure degassing device, it may be possible to collect gases (such as hydrogen) associated with the carbon particles at an elevated pressure. For example, hydrogen adsorbed in the pores of the carbon particles can be collected at the same elevated pressure as the pressure at which the reactor system is operating. By collecting the gas at an elevated pressure, it may be possible to use the gas in an elevated pressure system (such as high-pressure chemical synthesis, combustion, fuel cells, etc.) without using a secondary pressurization device. Therefore, due to the increase in the pressure of the gas, the gas can be used more easily in downstream processes. This can reduce the engineering requirements and improve the system function compared to when the gas pressure is low.

[0117] The carbon particle sample can be analyzed using a transmission electron microscope (TEM), a scanning electron microscope (SEM), ultrasonic dispersion according to ASTM D3849, or any combination thereof. TEM or SEM can be used to characterize the particle morphology. Ultrasonic dispersion can be carried out using chloroform to disperse the carbon particles on the surface of a mesh copper grid (such as a 200 mesh copper grid) supporting the hollow carbon film. The carbon particles can be further analyzed using Brunauer-Emmett-Teller (BET) analysis to characterize the primary particle size, DBP absorption to characterize the aggregate structure, transmission of toluene extract (TOTE) analysis, X-ray diffraction (XRD), or any combination thereof.

[0118] The exhaust gas can also be sampled and analyzed during the production of carbon particles and hydrogen. The exhaust gas can be sampled after the filtration system and before gas separation. The gas sampling can be carried out at individual time points or continuously. The sample gas can be delivered to a gas analysis bench. The gas analysis bench can include thermal conductivity detection (TCD), non-dispersive infrared analysis (NDIR), quantum cascade laser analysis (QCL), gas chromatography, Raman, Fourier transform infrared (FTIR), mass spectrometry, or any combination thereof. The gas sample analysis can include measuring the concentration profiles of various chemical species, including but not limited to methane, acetylene, ethylene, ethane, carbon oxides, or any combination thereof. In one example, carbon oxides (e.g., carbon monoxide, carbon dioxide, etc.) can be measured during the transient heating stage of the reactor. In another example, carbon oxides can be measured during all stages of the pyrolysis reaction. The gas analysis can be carried out during or after production to monitor the conversion of the hydrocarbon feedstock and the chemistry of the hydrocarbon feedstock conversion. Such analysis can further be used to determine the in-situ process conversion rate.

[0119] By monitoring the characteristics of carbon particles and exhaust gas during the production process, it may be possible to modulate process parameters to obtain targeted carbon particles. Process parameters that can be modulated can include, but are not limited to, plasma power, mixture temperature, flow rate, dilution rate, or any combination thereof.

[0120] By using a non-hydrogen plasma gas, the energy efficiency of the carbon particle generation process can be increased. In one example, by using a non-hydrogen plasma gas (e.g., a plasma gas containing about 50% or more non-hydrogen gas), it may be possible to generate carbon black with a larger surface area using approximately the same total energy input as in a similar process and system using a hydrogen plasma gas or a predominantly hydrogen-based plasma gas (e.g., about 80% or more hydrogen). In another example, by using a non-hydrogen plasma gas, it may be possible to generate carbon black with a larger surface area while keeping the energy input at the front end (e.g., plasma generation) lower than in a similar system and process using hydrogen as the plasma gas. For example, by using a non-hydrogen gas, it may be possible to reduce the energy usage in the reactor (e.g., for generating plasma) by 15%.

[0121] The non-hydrogen gas may not be consumed in the reaction. The non-hydrogen gas may be recycled back to the reactor. Due to leakage, a small amount of non-hydrogen gas may be lost from the system. The system can have low leakage in that about 80%, 85%, 90%, 95%, 98%, or more of the non-hydrogen gas can be returned to the reactor. In one example, about 90 volume percent (vol%) or more of the non-hydrogen gas provided to the reactor is returned to the reactor as a separated gas. In another example, about 98 vol% or more of the non-hydrogen gas provided to the reactor is returned to the reactor as a separated gas.

[0122] A small-scale three-phase alternating current (AC) plasma system may have a high energy intensity because a significant amount of energy is lost through the water cooling circuit (see, for example, Table 1 of Example 1 showing that the energy intensity for hydrogen generation can be approximately 100 and 86 kilowatt-hours per kilogram of hydrogen in Case A and Case B, respectively). The energy efficiency of a high-temperature thermal process can increase as the scale increases. See, for example, Example 2.

[0123] The systems and methods described herein can be integrated with, coupled to, or otherwise made available for use with one or more computer systems. The one or more computer systems may be configured to implement the methods described elsewhere herein, or may be operable to implement other methods, or may be configured to monitor the state of the systems described elsewhere herein. For example, one or more computer systems can be used to monitor the temperature of a product or apparatus at various points in a process, control or monitor process conditions such as the flow rate of a non-hydrogen gas, hydrocarbon feedstock, or separation gas, control or monitor the concentration of inlet or exhaust gas, control or monitor the pre-treatment or post-reactor state, or any combination thereof. The one or more computer systems may be configured to monitor, or may be capable of monitoring, the root mean square current and voltage of a plasma phase (e.g., each of the three phases for a three-phase system), the gas flow rate at the inlet and outlet, the temperature of the inlet and outlet water of a system including a water-cooling loop, the water flow rate per loop of a system including a water-cooling loop, or any combination thereof. The one or more computer systems can further monitor the internal temperature of the reactor wall at various locations within the reactor, for example, using an optical pyrometer and a type C thermocouple (e.g., a tungsten / rhenium-based thermocouple). The average reactor temperature may be used as, or as an estimate of, the average reaction temperature. Composition of carbon particles

[0124] The carbonaceous feedstock is C n H x or C n H x O ycan contain a chemical substance having the formula, where n is an integer, x is (i) between 1 and 2n + 2, or (ii) less than 1 (e.g., in the case of coal, coal tar, pyrolysis fuel oil, etc.), and y is between 0 and n. Examples of carbonaceous materials include linear hydrocarbons (e.g., methane, ethane, propane, butane, etc.), cyclic hydrocarbons (e.g., cyclopropane, cyclobutene, cyclopentane, cyclohexane, etc.), aromatic hydrocarbons (e.g., benzene, toluene, xylene, naphthalene, methylnaphthalene, pyrolysis fuel oil, coal tar, coal, heavy oil, oil, bio-oil, biodiesel, other biologically derived hydrocarbons, etc.), unsaturated hydrocarbons (e.g., ethylene, propylene, acetylene, butadiene, styrene, etc.), oxygenated hydrocarbons (e.g., alcohols, ethanol, propanol, phenol, ketones, esters, ethers, carboxylic acids, anhydrides, etc.), or any combination thereof, but are not limited thereto. The carbonaceous material can include a plurality of different carbonaceous materials. The carbonaceous feedstock or hydrocarbon can include at least about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or more different carbonaceous materials. The carbonaceous material can include at most about 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 different carbonaceous materials. The carbonaceous material can include at least about 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 96, 97, 98, 99, 99.9 or more weight percent of a single one of the aforementioned carbonaceous materials. The carbonaceous material can include at most about 99.9, 98, 97, 96, 95, 90, 85, 80, 75, 70, 65, 60, 55, 50, 45, 40, 35, 30, 25, 20, 15, 10, 5 or less weight percent of a single one of the aforementioned carbonaceous materials. For example, the carbonaceous material can include at least about 70 weight percent methane, ethane, or propane. In another example, the carbonaceous material can include at least about 70 weight percent of a mixture of methane, ethane, and propane. The carbonaceous material can include a single carbonaceous material in a weight percent defined by any two of the aforementioned values. For example, the carbonaceous material can include about 50 to about 70 percent of a single carbonaceous material.

[0125] The systems and methods described herein can produce carbon products that have a greater ratio of carbon-14 to carbon-12 than the same systems using fossil fuel hydrocarbon feedstocks. For example, carbon products produced using fossil fuel feedstocks may have a ratio of carbon-14 to carbon-12 of about 3×10 -13 or higher. The carbon products described herein may have a ratio of carbon-14 to carbon-12 of about 3×10 -13 or higher. The carbon products produced by the systems and methods described herein may have up to 10% more carbon-14 than carbon products produced from fossil fuel hydrocarbon feedstocks. The carbon products produced by the systems and methods described herein may have up to 5% more carbon-14 than carbon products produced from fossil fuel hydrocarbon feedstocks.

[0126] The carbonaceous material may contain carbon particles. The carbon particles may include carbon black. Examples of the carbon particles include, but are not limited to, carbon black, coke, needle coke, graphite, large-ring polycyclic aromatic hydrocarbons, activated carbon, etc., or any combination thereof. When operating at a pressure lower than the pressure of the process (e.g., about 1 bar, less than about 1.5 bar, etc.), the carbon particles can be produced by the process at a higher yield than the yield of the carbon particles formed by the reactor. The carbon particles can be produced at a yield of at least about 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 99.9 percent or higher. The carbon particles can be produced at a yield of at most about 99.9, 99, 98, 97, 96, 95, 94, 93, 92, 91, 90, 89, 88, 87, 86, 85, 84, 83, 82, 81, 80, 75, 70, 65, 60, 55, 50, 45, 40, 35, 30, 25, 20, 15, 10, 5 percent or less. The yield of the carbon particles can be a value within the range defined by any two of the aforementioned values. For example, the yield of the carbon particles can be about 90 to about 99 percent. The yield of the carbon particles in the process may be higher than the yield of the carbon particles formed in a different reactor of the same size as the reactor of the process when the different reactor operates at a pressure lower than the pressure of the reactor of the process.

[0127] The carbonaceous material (e.g., carbon particles) can be produced, for example, at a yield of about 1%, 5%, 10%, 25%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 99.5% or 99.9% or higher (e.g., as measured by the conversion rate of the raw material, based on the total hydrocarbons provided, based on the carbon weight percentage standard, or the molar number of carbon as the product relative to the molar number of carbon as the reactant). Alternatively or additionally, the carbonaceous material (e.g., carbon particles) can be produced, for example, at a yield of about 100%, 99.9%, 99.5%, 99%, 98%, 97%, 96%, 95%, 94%, 93%, 92%, 91%, 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, 50%, 25% or 5% or less (e.g., as measured by the conversion rate of the raw material, based on the total hydrocarbons provided, based on the carbon weight percentage standard, or the molar number of carbon as the product relative to the molar number of carbon as the reactant).

[0128] The carbon particles can include larger carbon particles. The larger carbon particles can have a spherical equivalent diameter of about 0.5, 0.6, 0.7, 0.75, 0.8, 0.9, 1, 1.1, 1.2, 1.25, 1.3, 1.4, 1.5, 1.6, 1.7, 1.75, 1.8, 1.9, 2, 2.1, 2.2, 2.25, 2.3, 2.4, 2.5, 2.6, 2.7, 2.75, 2.8, 2.9, 3, 4, 5 micrometers or larger. For example, the nitrogen surface area (N2SA) can be about 50, 40, 30, 20, 15, 10, 5 square meters per gram (m 2 / g), or may be smaller. For example, the larger carbon particles may have a sphere equivalent diameter of at least about 2 micrometers and an N2SA of less than about 15 square meters per gram. The larger carbon particles can be captured in a catchpot as described elsewhere in this specification. The carbon particles can include carbon particles having a sphere equivalent diameter of about 5, 4, 3, 2.9, 2.8, 2.75, 2.7, 2.6, 2.5, 2.4, 2.3, 2.25, 2.2, 2.1, 2, 1.9, 1.8, 1.75, 1.7, 1.6, 1.5, 1.4, 1.3, 1.25, 1.2, 1.1, 1, 0.9, 0.8, 0.75, 0.7, 0.6, 0.5, 0.4, 0.3, 0.25, 0.2, 0.1 micrometers or less. For example, the carbon particles may have a sphere equivalent diameter of less than about 2 micrometers. The ratio of the larger carbon particles (e.g., having a sphere equivalent diameter greater than about 2 micrometers) to the carbon particles having a sphere equivalent diameter of less than about 2 micrometers may be about 0 / 100, 5 / 95, 10 / 90, 15 / 85, 20 / 80, 25 / 75, 30 / 70, 35 / 65, 40 / 60, 45 / 55, 50 / 50, 55 / 45, 60 / 40, 65 / 35, 70 / 30, 75 / 25, 80 / 20, 85 / 15, 90 / 10, or 100 / 0. The methods and systems described herein can be configured to provide a predetermined ratio of the larger carbon particles to the carbon particles having a sphere equivalent diameter of less than about 2 micrometers. The sphere equivalent diameter can be measured by sedimometry.

[0129] The surface area of the carbon particles can be modified by changing the gas composition in the reactor (e.g., via the hydrogen concentration). The surface area of the carbon particles can be increased by reducing the hydrogen concentration or by generating the particles in the presence of one or more additives. Examples of additives include hydrocarbons (e.g., the hydrocarbons, hydrocarbon gases described elsewhere in this specification), silicon-containing compounds (e.g., siloxanes, silanes, etc.), aromatic additives (e.g., benzene, xylene, polycyclic aromatic hydrocarbons, etc.), or any combination thereof, but are not limited thereto. The reactor may be an oxygen-free environment. In one example, the carbon particles are produced in the absence of one or more additives (e.g., it may not be necessary to add additives to the reactor). The surface area (e.g., N2SA and / or statistical thickness surface area (STSA)) is about 5 m 2 / g, 10 m 2 / g, 15 m 2 / g, 20 m 2 / g, 25 m 2 / g, 30 m 2 / g, 35 m 2 / g, 40 m 2 / g, 45 m 2 / g, 50 m 2 / g, 60 m 2 / g, 70 m 2 / g, 80 m 2 / g, 81 m 2 / g, 90 m 2 / g, 100 m 2 / g, 120 m 2 / g, 140 m 2 / g, 160 m 2 / g, 180 m 2 / g, 200 m 2 / g, 250 m 2 / g, 300 m 2 / g, 350 m 2 / g, 400 m 2 / g or may be larger than that. Alternatively or additionally, the surface area (e.g., N2SA and / or STSA) is, for example, about 400 m 2 / g, 350 m 2 / g, 300 m 2 / g, 250 m 2 / g, 200 m 2 / g, 180 m 2 / g, 160 m 2 / g, 140 m 2 / g, 120 m 2 / g, 100 m 2 / g, 90 m 2 / g, 80 m 2 / g, 70 m 2 / g, 60 m 2 / g, 50 m 2 / g, 45 m 2 / g, 40 m 2 / g, 35 m 2 / g, 30 m 2 / g, 25 m 2 / g, 20 m 2 / g, 15 m 2 / g, 10 m 2 / g, 5 m 2 / g or less. STSA and N2SA may be different. This difference can be expressed in terms of the STSA / N2SA ratio. The STSA / N2SA ratio can be, for example, about 0.4, 0.5, 0.6, 0.7, 0.75, 0.76, 0.77, 0.78, 0.79, 0.8, 0.81, 0.82, 0.83, 0.84, 0.85, 0.86, 0.87, 0.88, 0.89, 0.9, 0.91, 0.92, 0.93, 0.94, 0.95, 0.96, 0.97, 0.98, 0.99, 1, 1.01, 1.02, 1.03, 1.03, 1.05, 1.06, 1.07, 1.08, 1.09, 1.1, 1.11, 1.12, 1.13, 1.14, 1.15, 1.16, 1.17, 1.19, 1.20, 1.21, 1.22, 1.23, 1.24, 1.25, 1.26, 1.27, 1.28, 1.29, 1.3, 1.31, 1.32, 1.33, 1.34, 1.35, 1.37, 1.38, 1.39, 1.4, 1.45, 1.5, 1.6, 1.7, 1.8, 1.9 or 2 or higher. Alternatively or additionally, the STSA / N2SA ratio can be, for example, about 2, 1.9, 1.8, 1.7, 1.6, 1.5, 1.45, 1.4, 1.39, 1.38, 1.37, 1.36, 1.35, 1.34, 1.33, 1.32, 1.31, 1.3, 1.29, 1.28, 1.27, 1.26, 1.25, 1.24, 1.23, 1.22, 1.21, 1.2, 1.19, 1.18, 1.17, 1.16, 1.15, 1.14, 1.13, 1.12, 1.11, 1.1, 1.09, 1.08, 1.07, 1.06, 1.05, 1.04, 1.03, 1.02, 1.01, 1, 0.99, 0.98, 0.97, 0.96, 0.95, 0.94, 0.93, 0.92, 0.91, 0.9, 0.89, 0.88, 0.87, 0.86, 0.85, 0.84, 0.83, 0.82, 0.81, 0.8, 0.79, 0.78, 0.77, 0.76, 0.75, 0.7, 0.6 or 0.5 or less. In some examples, the surface area (e.g., N2SA or specific surface area) is about about 40 m 2 / g to about 200 m 2 / g. The carbon particle(s) may have such a surface area, along with one or more other properties described herein. The carbon particle or additional carbon particles may have a nitrogen surface area (N2SA) of at least 80 m 2 / g. The carbon particle, additional carbon particles, or both may have a specific surface area of at least about 50 square meters (m 2 / g) per gram. The carbon particle or additional carbon particles may have a surface area of about 50 m 2 / g to 200 m 2 / g.

[0130] Carbon particles (e.g., carbon black particles) can have a predetermined structure. The structure can be expressed in terms of dibutyl phthalate (DBP) absorption, which determines the amount of DBP that a given mass of carbon particles (e.g., carbon black) can absorb before reaching a specified viscous rheology target torque, thereby measuring the relative structure of the carbon particles (e.g., carbon black). The structure of the carbon particles can be modified, as described elsewhere herein, by generating the particles in the presence of an additive that breaks up particle aggregation and reduces the structure. Alternatively or additionally, the structure of the carbon particles can be modulated by varying the hydrogen concentration in the reactor. The carbon particles may have a DBP absorption of at least about 20 milliliters per 100 grams of carbon black (mL / 100g), 30 mL / 100g, 40 mL / 100g, 50 mL / 100g, 60 mL / 100g, 80 mL / 100g, 100 mL / 100g, 125 mL / 100g, 150 mL / 100g, 200 mL / 100g, 250 mL / 100g, 300 mL / 100g, 400 mL / 100g, 500 mL / 100g or more. The carbon particles may have a DBP absorption of about 500 mL / 100g, 400 mL / 100g, 300 mL / 100g, 250 mL / 100g, 200 mL / 100g, 150 mL / 100g, 125 mL / 100g, 100 mL / 100g, 80 mL / 100g, 60 mL / 100g, 50 mL / 100g, 40 mL / 100g, 30 mL / 100g, 20 mL / 100g or less. In one example, the carbon particles may be produced in the absence of an additive (e.g., potassium) and may have a structure of about 100 mL / 100g or more. In another example, the carbon particles may be produced in the absence of an additive (e.g., potassium) and may have a structure of about 150 mL / 100g or more.

[0131] The systems and methods of the present disclosure are incorporated herein by reference in their entireties: U.S. Patent Application Publication No. 2015 / 0210856 and International Patent Application Publication No. 2015 / 116807 ("SYSTEM FOR HIGH TEMPERATURE CHEMICAL PROCESSING"), U.S. Patent Application Publication No. 2015 / 0211378 ("INTEGRATION OF PLASMA AND HYDROGEN PROCESS WITH COMBINED CYCLE POWER PLANT, SIMPLE CYCLE POWER PLANT AND STEAM REFORMERS"), International Patent Application Publication No. 2015 / 116797 ("INTEGRATION OF PLASMA AND HYDROGEN PROCESS WITH COMBINED CYCLE POWER PLANT AND STEAM REFORMERS"), U.S. Patent Application Publication No. 2015 / 0210857 and International Patent Application Publication No. 2015 / 116798 ("USE OF FEEDSTOCK IN CARBON BLACK PLASMA PROCESS"), U.S. Patent Application Publication No. 2015 / 0210858 and International Patent Application Publication No. 2015 / 116800 ("PLASMA GAS THROAT ASSEMBLY AND METHOD"), U.S. Patent Application Publication No. 2015 / 0218383 and International Patent Application Publication No. 2015 / 116811 ("PLASMA REACTOR"), U.S. Patent Application Publication No. 2015 / 0223314 and International Patent Application Publication No. 2015 / 116943 ("PLASMA TORCH DESIGN"), International Patent Application Publication No. 2016 / 126598 ("CARBON BLACK COMBUSTABLE GAS SEPARATION"), International Patent Application Publication No. 2016 / 126599 ("CARBON BLACK GENERATING SYSTEM"), International Patent Application Publication No. 2016 / 126600 ("REGENERATIVE COOLING METHOD AND APPARATUS"), U.S. Patent Application Publication No. 2017 / 0034898 and International Patent Application Publication No. 2017 / 019683 ("DC PLASMA TORCH ELECTRICAL POWER DESIGN"METHOD AND APPARATUS", U.S. Patent Application Publication No. 2017 / 0037253 and International Patent Application Publication No. 2017 / 027385 ("METHOD OF MAKING CARBON BLACK"), U.S. Patent Application Publication No. 2017 / 0058128 and International Patent Application Publication No. 2017 / 034980 ("HIGH TEMPERATURE HEAT INTEGRATION METHOD OF MAKING CARBON BLACK"), U.S. Patent Application Publication No. 2017 / 0066923 and International Patent Application Publication No. 2017 / 044594 ("CIRCULAR FEW LAYER GRAPHENE"), U.S. Patent Application Publication No. 20170073522 and International Patent Application Publication No. 2017 / 048621 ("CARBON BLACK FROM NATURAL GAS"), International Patent Application Publication No. 2017 / 190045 ("SECONDARY HEAT ADDITION TO PARTICLE PRODUCTION PROCESS AND APPARATUS"), International Patent Application Publication No. 2017 / 190015 ("TORCH STINGER METHOD AND APPARATUS"), International Patent Application Publication No. 2018 / 165483 ("SYSTEMS AND METHODS OF MAKING CARBON PARTICLES WITH THERMAL TRANSFER GAS"), International Patent Application Publication No. 2018 / 195460 ("PARTICLE SYSTEMS AND METHODS"), International Patent Application Publication No. 2019 / 046322 ("PARTICLE SYSTEMS AND METHODS"), International Patent Application Publication No. 2019 / 046320 ("SYSTEMS AND METHODS FOR PARTICLE GENERATION"), International Patent Application Publication No. 2019 / 046324 ("PARTICLE SYSTEMS AND METHODS"), International Patent Application Publication No. 2019 / 084200 ("PARTICLE SYSTEMS AND METHODS"), as well as International Patent Application Publication No. 2019 / 195461 ("SYSTEMS AND METHODS FOROther systems or methods (with appropriate modifications, if any) described in "PROCESSING"), for example, chemical treatment and heating methods, chemical treatment systems, reactors, and can be combined with or modified by plasma torches.

Examples

[0132] (Example 1) Nitrogen and mixed nitrogen dilution gas The methane conversion rate, carbon particle yield, and hydrogen yield can vary as a function of the composition of the dilution gas. Case A and Case B can show the experimental results of two different dilution gas compositions. The dilution gas can be a gas that can be used or is used to generate plasma. In one example, as described elsewhere herein, the volumetric flow rate dilution ratio (DR) can be maintained at 7 for both Case A and Case B. Table 1 shows a summary example of the process conditions and yield results for Case A and Case B. As shown in Table 1, the process parameters for Case A and Case B can be substantially the same. The process conditions can be substantially the same for Case A and Case B, except for the ratio of hydrogen to nitrogen. For example, in Case A, the ratio of hydrogen to nitrogen in the plasma gas can be approximately 0 to 100, and in Case B, the ratio of nitrogen to hydrogen can be approximately 30 to 70. In both cases, the plasma gas flow rate can be approximately 28 Nm 3 / h, and the dilution ratio can be fixed at 7. Table 1. Process parameters and yields for Case A and Case B

Table 1

[0133] As shown in Figure 5, the average reactor temperature can change by approximately 100 °C over the methane injection process. The reaction times for Case A and Case B are approximately 40 minutes, which may be sufficient time to produce a sufficient amount of solid product for subsequent analysis. At the start of methane injection, the temperature of the reactor rises due to the beginning of the particle-containing flow, thereby enhancing heat transfer by radiation and assisting in the transfer of thermal energy from the plasma to the product gas. As shown in Figure 5, Case A can reach a quasi-thermal steady state within about 20 minutes. In Case B, heating of the reactor is time-consuming, and thus a thermal steady state may be possible during methane injection.

[0134] As shown in Table 1, the methane conversion rates for both cases exceed 99%, reaching 99.5% for Case A and 99.9% for Case B. The high conversion rates are economically advantageous on a commercial scale. The high methane conversion rates result in high hydrogen yields under both conditions, reaching, for example, 96% for Case A and 98% for Case B. The remaining hydrogen may be contained in other gas-phase hydrocarbons such as acetylene, ethylene, and other species that may or may not be measurable by the gas analysis measurement means.

[0135] The total elemental carbon balance can be carried out for each run and may include the carbon mass generated and estimated from the gas analysis measurement means. In this method, hydrocarbons larger than ethane may not be considered, and compounds formed and removed from the reactor may not be included in the carbon balance. The remaining carbon that may not be converted to solid form can be estimated based on the gas analysis data and can reach 5% for both Case A and Case B.

[0136] The carbon balance of Case A can reach 100%, while that of Case B can reach 97%. The 100% carbon balance in Case A may suggest that after the process gas exits the reactor, there cannot be a large amount of larger intermediate species such as aromatics. Alternatively, the inability to reach a 100% carbon balance in Case B may suggest that the conversion of the raw materials is incomplete and that there are persistent intermediate gas-phase species that cannot be traced by the gas analysis measurement means.

[0137] Table 2 shows a comparison of the characteristics of the solid carbon obtained from the analysis along with examples from the literature. Such a comparison cannot directly indicate the performance of the bulk plasma black in industrial applications such as rubber compounding, but it may provide a means to compare with other ASTM standard carbon blacks. By further adjusting the reactor conditions, a specific grade of carbon black can be obtained. In both cases, the bulk solid carbon can be produced with a yield exceeding 90%. As shown in Table 2, X-ray diffraction (XRD) can be performed on the bulk carbon sample of Case A. For comparison, the lattice constant (Lc) of the carbon black produced by the furnace process can be between 1 and 3. In both cases, the surface area of the produced carbon can be in the range of 90 - 110 m 2 / g, which can be in good agreement with the surface area of the furnace black (e.g., 80 - 100 m 2 / g) used for reinforcing grade applications. The concentration of the toluene extract can be similar to that from the furnace process. Table 2. Comparison of Selected Solid Carbon Analysis Data with Selected Furnace Blacks (N660, N330) and Acetylene Black Data

Table 2

[0138] Figures 6A and 6B show TEM images obtained from the samples of Case A to investigate the morphology of the particles. The particles can have an aggregated morphology similar to carbon black, but the primary particles do not appear as spherical as furnace-type black and do not appear turbostratic either. This difference in appearance may be due to the higher reactor temperature and product yield used for raw material conversion compared to the furnace process. (Example 2) Energy intensity of methane pyrolysis

[0139] As shown in Table 2 above, the energy intensity of a small-scale three-phase alternating current (AC) plasma system can be high because energy is lost in the water cooling circuit. For example, the energy intensity of hydrogen production in Case A can be approximately 100 kilowatt-hours per kilogram of hydrogen (kWh / kg H2), and the energy intensity of hydrogen production in Case B can be approximately 86 kWh / kg H2.

[0140] The energy efficiency of the high-temperature thermal process can increase as the scale increases. Table 3 shows a potential example of real-time operation data for an industrial-scale facility with 12 units and a production capacity of 50 kilotons of hydrogen and 180 kilotons of carbon black per year. The energy intensity obtained at this scale can be approximately 25 kWh / kg H2. This energy intensity can be approximately 42% of the energy intensity of hydrogen production using water electrolysis (approximately 60 kWh / kg H2). Table 3. Examples of annual energy usage for industrial-scale carbon black and hydrogen production with and without using hydrogen as a process gas

Table 3

[0141] Carbon particles can be produced in a plasma pyrolysis reactor. The plasma source can operate at a reaction temperature of at least about 500 kilowatts (kW) and 1750 °C, and can operate at a carbon production rate of at least about 100 kilograms per hour (kg / h). In tests using low molecular weight reaction gases and high concentrations of hydrogen, carbon samples can be produced. The surface area of the resulting carbon particles is at least about 5 square meters per gram (m 2 / g), and can fall within the range of the semi-reinforcing grade of standard carbon black for tire manufacturing. Equivalent tests can be performed by modulating the hydrogen composition of the plasma or dilution gas while maintaining other process parameters constant. By increasing the molecular weight of the plasma gas and reducing the concentration of hydrogen gas, the surface area of the produced carbon particles increases and can fall within the range of the reinforcing grade of carbon black that can be used in tire manufacturing. (Example 4) Production of Carbon Particles in a Reduced Hydrogen Environment

[0142] Using a laboratory-scale methane pyrolysis reactor, carbon particles and hydrogen can be produced. The reactor can include a plasma torch that injects methane feedstock into the heated gas after heating the gas. The gas can be quenched to stop the reaction after a certain period of time in a high-temperature reaction chamber. In the reaction chamber, the methane feedstock can be converted to hydrogen and carbon black. The data provided below can be created by collecting the carbon produced by the reactor and analyzing it according to ASTM methods. Table 4 shows examples of conditions that can be used to produce carbon black. Table 4. Examples of Operating Conditions for Hydrogen Concentration Tests

Table 4-1

Table 4-2

[0143] The amount of hydrogen in the reactor can be expressed as the concentration of the total amount of non-feedstock gas entering the system. This can be expressed as a mole percentage of the total flow rate and may be abbreviated as H2%. Figure 7 shows an example of the carbon particle surface area as a function of hydrogen concentration. The surface area of the carbon particles can be measured by the nitrogen surface area (N2SA). Figure 7 shows the linear regression of the dataset. As the amount of hydrogen in the gas phase of the reactor increases, the surface area of the carbon particles can decrease. Alternatively, as the amount of hydrogen decreases, the surface area of the particles can increase. The data shown in Figure 7 can be obtained from two different shaped reactors, and the change in shape does not affect the surface area of the carbon particles. Figure 8 shows an example of the structure (DBP) as a function of hydrogen concentration. Similar to the normalized surface area, the structure can increase as the hydrogen concentration decreases. The data shown in Figure 8 is from the shape of a single reactor. Figure 9 shows an example of the effect of hydrogen concentration on the amount of unreacted hydrocarbons at a given reactor temperature. As the amount of hydrogen gas in the reactor increases, the amount of residual hydrocarbons also increases. For example, if the hydrogen concentration in the reactor increases by 15%, the amount of unreacted hydrocarbons can more than double.

[0144] Figure 10 shows an example of data indicating the influence of hydrogen content on carbon particle recovery rate and fouling at substantially the same reaction temperature. As shown in Figure 10, carbon can exit the reactor via the recovered product, wall fouling, catch pot carbon mass, and flue gas carbon in the form of unreacted hydrocarbons. The catch pot may be a stainless steel container attached to the reactor outlet, which may be capable of holding fouling substances falling from various internal components of the reactor during operation. The catch pot may be provided with a port into which a quench gas can be injected. Fouling may be too large to be entrained in the exhaust gas and may fall into the catch pot by gravity, while carbon particles can be entrained in the exhaust stream. The catch pot carbon mass may include solid fouling from the wall that has fallen into the catch pot. The amount of product recovered can be greater when the hydrogen concentration is 0% than when it is 35%. In addition, when the hydrogen concentration is low, the amount of wall fouling can be reduced compared to a higher hydrogen concentration. An increase in the carbon mass of the catch pot may indicate that the wall fouling may not adhere firmly to the wall. Fouling that does not adhere firmly to the wall may be easier to remove and manage during maintenance intervals. Figure 11 shows an example of wear of the apparatus as a function of hydrogen concentration in the reactor. At substantially the same temperature, a reactor with a hydrogen concentration of 0% shows substantially less component wear than a reactor with a hydrogen concentration of 35%. For example, wear of the plasma chamber can be substantially eliminated while erosion of the electrodes can be significantly reduced. Overall, the reduction in wear is approximately 90%, which can result in a significant reduction in consumable costs.

[0145] Preferred embodiments of the present invention have been shown and described herein, but it will be apparent to those skilled in the art that such embodiments are provided by way of example only. It is not intended that the present invention be limited by the specific examples provided herein. The present invention has been described with reference to the foregoing specification, but the description and illustration of the embodiments herein are not meant to be construed in a limiting sense. Those skilled in the art will envision numerous variations, modifications, and substitutions without departing from the present invention. Furthermore, it should be understood that all aspects of the present invention are not limited to the specific depictions, configurations, or relative proportions described herein, which vary according to various conditions and variables. It should be understood that various alternatives to the embodiments of the present invention described herein may be used in the practice of the present invention. Therefore, the present invention is intended to cover any such alternatives, modifications, changes, or equivalents thereof. The following claims define the scope of the present invention, and it is intended that methods and structures within the scope of these claims, as well as their equivalents, be protected thereby.

Claims

1. A method for producing carbon particles, (a) In a reactor, a non-hydrogen gas is brought into contact with a hydrocarbon raw material in the presence of plasma, thereby obtaining an exhaust gas containing (i) carbon particles and (ii) hydrogen and the non-hydrogen gas, (b) Separating at least a portion of the hydrogen from the non-hydrogen gas of the exhaust gas to obtain a separated gas containing the non-hydrogen gas, (c) Providing the separation gas or a derivative thereof containing the non-hydrogen gas to the reactor, (d) A method comprising contacting the separation gas or a derivative thereof containing the non-hydrogen gas with a further hydrocarbon feedstock in the presence of the plasma to obtain (iii) further carbon particles and (iv) further exhaust gas containing hydrogen and the non-hydrogen gas.

2. The method according to claim 1, wherein the non-hydrogen gas comprises one or more gases selected from the group consisting of nitrogen, helium, neon, krypton, argon, carbon monoxide, and carbon dioxide.

3. The method according to claim 1, wherein the separation gas or its derivative contains 50 mol% (mol%) or less of hydrogen.

4. The method according to claim 1, further comprising providing the non-hydrogen gas and a gas mixture containing hydrogen to the reactor in (a), wherein the gas mixture has (i) an average molecular weight of 1 kg / kmol to 90 kg / kmol, or (ii) a ratio of the non-hydrogen gas to hydrogen of at least 2 to 1.

5. The method according to claim 1, further comprising providing the separation gas or a derivative thereof and a gas mixture containing hydrogen to the reactor in (c).

6. The method according to claim 5, wherein in (d), the ratio of the non-hydrogen gas to the hydrogen is at least 2 to 1.

7. (c) The method according to claim 1, wherein hydrogen is not supplied to the reactor during or after the reactor.

8. The method according to claim 1, further comprising contacting the non-hydrogen gas with the hydrocarbon raw material at a temperature of 1900°C or less in (a).

9. The method according to claim 1, further comprising contacting the separated gas or its derivative with the further hydrocarbon raw material at a temperature of 1900°C or less in (d).

10. The carbon particles or the further carbon particles have a density of at least 40 square meters (m²) per gram. ２ The method according to claim 1, having a nitrogen surface area (N2SA) of 1 / g.

11. The method according to claim 1, wherein the carbon particles or further carbon particles have an absorption capacity of at least 100 milliliters (mL / 100g) of dibutyl phthalate (DBP) per 100 grams of carbon particles.

12. The method according to claim 11, wherein the carbon particles are produced in the presence of an additive that inhibits the aggregation of the carbon particles.

13. The method according to claim 1, wherein in (a), at least 80% of the hydrocarbon raw material is converted to the carbon particles, or in (d), at least 80% of the further hydrocarbon raw material is converted to the further carbon particles.

14. The method according to claim 1, further comprising providing an energy input to generate the plasma, wherein the energy input per kilogram of hydrogen produced is at least 15% less in a gas mixture containing at least 50 mol% of non-hydrogen gas compared to another gas mixture containing 80 mol% or more of hydrogen.

15. The method according to claim 1, wherein 90% or more of the non-hydrogen gas supplied to the reactor is returned to the reactor as the separated gas.

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