Abstract: A carbon pitch or dry coke is produced by reacting a mixture of carbon dioxide and hydrogen in a reactor at a predetermined temperature and pressure with an iron catalyst being fed into the reactor, using a process that also involves production of methane from the reaction gases. The reaction product is cooled. The reaction product may be graphitized in a reaction vessel under reduced pressure, heating the vessel at a predetermined rate and injecting an inert gas flow. The vessel is heated to a temperature of between 1600° C. and 2800° C. and maintained at that temperature for hours. The vessel is cooled and the reaction products removed.

Abstract: Methods of forming solid carbon products include disposing nanostructure carbon in a container, disposing the container in a press, compressing the nanostructured carbon within the container, and fastening a lid to the container to form a filter. Further processing may include sintering the nanostructured carbon within the container and heating the nanostructured carbon within the container in an inert environment to form bonds between adjacent particles of nanostructured carbon. Other methods may include forming a plurality of compressed nanostructured carbon modules, placing the plurality of compressed nanostructured carbon modules within a container, and placing a lid on the container to form a filter structure. Related structures are also disclosed.

Abstract: Methods of forming solid carbon products include disposing nanostructure carbon in a container, disposing the container in a press, compressing the nanostructured carbon within the container, and fastening a lid to the container to form a filter. Further processing may include sintering the nanostructured carbon within the container and heating the nanostructured carbon within the container in an inert environment to form bonds between adjacent particles of nanostructured carbon. Other methods may include forming a plurality of compressed nanostructured carbon modules, placing the plurality of compressed nanostructured carbon modules within a container, and placing a lid on the container to form a filter structure. Related structures are also disclosed.

Abstract: Methods of forming solid carbon products include disposing nanostructure carbon in a container, disposing the container in a press, compressing the nano structured carbon within the container, and fastening a lid to the container to form a filter. Further processing may include sintering the nanostructured carbon within the container and heating the nanostructured carbon within the container in an inert environment to form bonds between adjacent particles of nanostructured carbon. Other methods may include forming a plurality of compressed nanostructured carbon modules, placing the plurality of compressed nanostructured carbon modules within a container, and placing a lid on the container to form a filter structure. Related structures are also disclosed.

Abstract: Methods of forming solid carbon products include disposing a plurality of nanotubes in a press, and applying heat to the plurality of carbon nanotubes to form the solid carbon product. Further processing may include sintering the solid carbon product to form a plurality of covalently bonded carbon nanotubes. The solid carbon product includes a plurality of voids between the carbon nanotubes having a median minimum dimension of less than about 100 nm. Some methods include compressing a material comprising carbon nanotubes, heating the compressed material in a non-reactive environment to form covalent bonds between adjacent carbon nanotubes to form a sintered solid carbon product, and cooling the sintered solid carbon product to a temperature at which carbon of the carbon nanotubes do not oxidize prior to removing the resulting solid carbon product for further processing, shipping, or use.

Abstract: A method for production of various morphologies of solid carbon product by reducing carbon oxides with a reducing agent in the presence of a catalyst. The carbon oxides are typically either carbon monoxide or carbon dioxide. The reducing agent is typically either a hydrocarbon gas or hydrogen. The desired morphology of the solid carbon product may be controlled by the specific catalysts, reaction conditions, and optional additives used in the reduction reaction. The resulting solid carbon products have many commercial applications.

Abstract: A reaction apparatus for use in solid carbon production includes a reactor shell defining a reactor inlet and a reactor outlet. Concentric cylinders or substantially parallel plates of catalytic material are disposed within the reactor shell and are structured and adapted to expose at least one contact surface to gaseous reactants. Another apparatus includes a removable cartridge comprising a plurality of substantially parallel plates of catalytic material disposed within the reactor shell. A system for use in carbon nanotube production may include any such reactor and a solids recovery means for removing carbon nanotubes from the reactor.

Abstract: Methods of forming solid carbon products include disposing nanostructure carbon in a container, disposing the container in a press, compressing the nano structured carbon within the container, and fastening a lid to the container to form a filter. Further processing may include sintering the nanostructured carbon within the container and heating the nanostructured carbon within the container in an inert environment to form bonds between adjacent particles of nanostructured carbon. Other methods may include forming a plurality of compressed nanostructured carbon modules, placing the plurality of compressed nanostructured carbon modules within a container, and placing a lid on the container to form a filter structure. Related structures are also disclosed.

Abstract: Methods of concurrently forming ammonia and solid carbon products include reacting a carbon oxide, nitrogen, and a reducing agent at preselected reaction conditions in the presence of a catalyst to form a solid carbon product entrained in a tail gas mixture comprising water and ammonia; separating entrained solid carbon product from the tail gas mixture; and recovering water and ammonia from the tail gas mixture. Systems for forming ammonia and solid carbon products from a gaseous source containing carbon oxides include mixing means for mixing the gaseous source with a reducing agent, reactor means for reacting at least a portion of the gaseous source with the reducing agent in the presence of a catalyst to produce the solid carbon products and a tail gas mixture comprising the ammonia, and solid separation means for separating the solid carbon products from the tail gas mixture.

Abstract: An apparatus for producing solid carbon and water by reducing carbon oxides with a reducing agent in the presence of a catalyst includes a reactor configured to receive reaction gas comprising at least one carbon oxide, at least one reducing agent, and water. The apparatus includes at least one mixing means configured to mix the reagents to form a combined feed, a first heat exchanger configured to heat the combined feed, at least one heater configured to further heat the combined feed, and a reaction vessel configured to receive the combined feed. The reaction vessel is configured to contain a catalyst, to maintain predetermined reaction conditions of temperature and pressure, and has an output configured to deliver a tail gas to the first heat exchanger. The system also includes a product separator, a water separation unit, and a product packaging unit.

Abstract: A method of producing forests of fibrous solid carbon includes providing a catalyst material over a substrate, forming the catalyst material into catalyst nanoparticles, and reacting carbon monoxide with hydrogen in the presence of the catalyst nanoparticles to form forests of fibrous solid carbon attached to the catalyst nanoparticles. A composition of matter includes an inert material disposed upon a substrate, a plurality of nanoparticles of catalyst material upon the inert material, and a plurality of carbon nanotubes upon the nanoparticles. Some methods of producing a forest of carbon nanotubes include preparing a catalyst surface by depositing an inert material onto stainless steel, and depositing iron onto the inert material. The catalyst surface is placed into a furnace chamber, and the furnace chamber is heated.

Abstract: An electrode includes a network of compressed interconnected nanostructured carbon particles such as carbon nanotubes. Some nanostructured carbon particles of the network are in electrical contact with adjacent nanostructured carbon particles. Electrodes may be used in various devices, such as capacitors, electric arc furnaces, batteries, etc. A method of producing an electrode includes confining a mass of nanostructured carbon particles and densifying the confined mass of nanostructured carbon particles to form a cohesive body with sufficient contacts between adjacent nanostructured carbon particles to provide an electrical path between at least two remote points of the cohesive body. The electrodes may be sintered to induce covalent bonding between the nanostructured carbon particles at contact points to further enhance the mechanical and electrical properties of the electrodes.

Abstract: A method of treating an offgas includes purifying the offgas to remove particulate matter, water, undesirable gaseous components and inert gases to produce a dried carbon oxide gas feedstock, and converting at least a portion of carbon oxides in the dried carbon oxide gas feedstock into solid carbon. In other embodiments, a method includes passing a dried carbon oxide gas feedstock through a multi-stage catalytic converter. A first stage is configured to catalyze methane-reforming reactions to convert methane into carbon dioxide, carbon monoxide and hydrogen with residual methane. A second stage is configured to catalyze the Bosch reaction and convert carbon oxides and hydrogen to solid carbon and water.

Abstract: A reactor includes a vessel, a gas inlet, a solid outlet, a catalyst support configured to at least partially retain a catalyst material and allow a tail gas to pass therethrough, and a tail gas outlet. The gas inlet is in fluid communication with the solid outlet. A system for producing a solid product includes a reactor, a compressor, a heater, a make-up reactive gas inlet, and a solids discharge means for removing the solid product from the solid outlet of the reactor. Methods of forming solid products include providing a catalyst material in a vessel having a porous catalyst support, delivering a reactive gas to the vessel, reacting the reactive gas to form a solid product and a tail gas in the vessel, passing the tail gas through a portion of the catalyst material to separate the solid product from the tail gas, and removing the solid product.

Abstract: A reactor for producing a solid carbon material comprising at least one reaction chamber configured to produce a solid carbon material and water vapor through a reduction reaction between at least one carbon oxide and at least one gaseous reducing material in the presence of at least one catalyst material. Additional reactors, and related methods of producing a solid carbon material, and of forming a reactor for producing a solid carbon material are also described.

Abstract: A composition comprising a mixture of carbon nanotubes having a bi-modal size distribution are produced by reducing carbon oxides with a reducing agent in the presence of a catalyst. The resulting mixture of nanotubes include a primary population of multiwall carbon nanotubes having characteristic diameters greater than 40 nanometers, and a secondary population of what are apparently single wall nanotubes with characteristic diameters of less than 30 nanometers. The resulting mixture may also contain one or more other allotropes and morphologies of carbon in various proportions.

Abstract: Methods of forming solid carbon products include disposing a plurality of nanotubes in a press, and applying heat to the plurality of carbon nanotubes to form the solid carbon product. Further processing may include sintering the solid carbon product to form a plurality of covalently bonded carbon nanotubes. The solid carbon product includes a plurality of voids between the carbon nanotubes having a median minimum dimension of less than about 100 nm. Some methods include compressing a material comprising carbon nanotubes, heating the compressed material in a non-reactive environment to form covalent bonds between adjacent carbon nanotubes to form a sintered solid carbon product, and cooling the sintered solid carbon product to a temperature at which carbon of the carbon nanotubes do not oxidize prior to removing the resulting solid carbon product for further processing, shipping, or use.

Abstract: A method of reducing a gaseous carbon oxide includes reacting a carbon oxide with a gaseous reducing agent in the presence of a non-ferrous catalyst. The reaction proceeds under conditions adapted to produce solid carbon of various allotropes and morphologies, the selective formation of which can be controlled by means of controlling reaction gas composition and reaction conditions including temperature and pressure. A method for utilizing a non-ferrous catalyst in a reactor includes placing the catalyst in a suitable reactor and flowing reaction gases comprising a carbon oxide with at least one gaseous reducing agent through the reactor where, in the presence of the catalyst, at least a portion of the carbon in the carbon oxide is converted to solid carbon and a tail gas mixture containing water vapor.

Abstract: A method of reducing a gaseous carbon oxide includes reacting a carbon oxide with a gaseous reducing agent in the presence of an intermetallic or carbide catalyst. The reaction proceeds under conditions adapted to produce solid carbon of various allotropes and morphologies, the selective formation of which can be controlled by means of controlling reaction gas composition and reaction conditions including temperature and pressure. A method for utilizing an intermetallic or carbide catalyst in a reactor includes placing the catalyst in a suitable reactor and flowing reaction gases comprising a carbon oxide with at least one gaseous reducing agent through the reactor where, in the presence of the catalyst, at least a portion of the carbon in the carbon oxide is converted to solid carbon and a tail gas mixture containing water vapor.

Abstract: A method for producing hydrogen, includes heating a process feed gas stream, flowing the process feed gas stream into a first reaction zone, flowing the intermediate gas stream into a second reaction zone, removing the solid carbon product from the second reaction zone, removing the tail gas stream from the second reaction zone, and removing hydrogen from the tail gas stream. The process gas stream includes methane and steam. The first reaction zone contains a first catalyst, and at least a portion of the process feed gas stream is converted into an intermediate gas stream in the first reaction zone. The second reaction zone contains a second catalyst, and at least a portion of the intermediate gas stream is converted into a tail gas stream and a solid carbon product in the second reaction zone.