C01B32/205

METHOD AND SYSTEM FOR CONVERTING RAW COAL POWDER INTO POLYCRYSTALLINE NANO-GRAPHITE BY METAL-ASSISTED MICROWAVE TREATMENT
20220363547 · 2022-11-17 · ·

A metal-assisted microwave treatment that converting raw coal powders into nano-graphite is presented. Specifically, four major factors are identified for successful conversion: (1) high temperature; (2) reducing environment; (3) catalyst; and (4) microwave radiation. Specifically, it is determined that the combination of the carbon sources (raw coal powders), the high temperature (microwave induced electric sparking), the reducing environment (the Ar/H.sub.2 mixture), the catalyst (Cu foil), with the microwave radiations can generate nano-graphite. This novel approach utilizes the sparking induced by the microwave radiation on the fork-shape metal foils to generate high temperature (>1000° C.) within few seconds. The small thermal load makes this method cost effective and has potential for higher temperature using metals with higher melting temperature. Refinement of this technique is possible to yield a higher quality and quantity of nano-graphite materials for a wider range of applications.

METHOD AND SYSTEM FOR CONVERTING RAW COAL POWDER INTO POLYCRYSTALLINE NANO-GRAPHITE BY METAL-ASSISTED MICROWAVE TREATMENT
20220363547 · 2022-11-17 · ·

A metal-assisted microwave treatment that converting raw coal powders into nano-graphite is presented. Specifically, four major factors are identified for successful conversion: (1) high temperature; (2) reducing environment; (3) catalyst; and (4) microwave radiation. Specifically, it is determined that the combination of the carbon sources (raw coal powders), the high temperature (microwave induced electric sparking), the reducing environment (the Ar/H.sub.2 mixture), the catalyst (Cu foil), with the microwave radiations can generate nano-graphite. This novel approach utilizes the sparking induced by the microwave radiation on the fork-shape metal foils to generate high temperature (>1000° C.) within few seconds. The small thermal load makes this method cost effective and has potential for higher temperature using metals with higher melting temperature. Refinement of this technique is possible to yield a higher quality and quantity of nano-graphite materials for a wider range of applications.

Carbon material and method for producing same

(Problem) In conventional method for producing artificial graphite, in order to obtain a product having excellent crystallinity, it was necessary to mold a filler and a binder and then repeat impregnation, carbonization and graphitization, and since carbonization and graphitization proceeded by a solid phase reaction, a period of time of as long as 2 to 3 months was required for the production and cost was high and further, a large size structure in the shape of column and cylinder could not be produced. In addition, nanocarbon materials such as carbon nanotube, carbon nanofiber and carbon nanohorn could not be produced. (Means to solve) A properly pre-baked filler is sealed in a graphite vessel and is subsequently subjected to hot isostatic pressing (HIP) treatment, thereby allowing gases such as hydrocarbon and hydrogen to be generated from the filler and precipitating vapor-phase-grown graphite around and inside the filler using the generated gases as a source material, and thereby, an integrated structure of carbide of the filler and the vapor-phase-grown graphite is produced. In addition, nanocarbon materials are produced selectively and efficiently by adding a catalyst or adjusting the HIP treating temperature.

Carbon oxide reduction with intermetallic and carbide catalysts
09783421 · 2017-10-10 · ·

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.

Graphite film

Provided is a long and large-area graphite film having improved thermal diffusivity and flex resistance, and accompanied by ameliorated ruffling. According to a method for producing a graphite film, in which graphitization of a heat-treated film consisting of a carbonized polymer film is carried out in a state being wrapped around an internal core, the method being characterized in that a heat treatment is executed by controlling distance(s) between the internal core and the film, and/or between the layers of the film, a graphite film accompanied by significantly ameliorated ruffling can be obtained.

SYNTHESIS OF GRAPHITIC SHELLS ON SILICON NANOPARTICLES
20220052323 · 2022-02-17 ·

Discussed herein are methods for making an anode material comprising silicon nanoparticles and a graphite carbon coating thereon. The method can include providing silicon nanoparticles, applying an amorphous carbon coating thereon to create an amorphous carbon shell on the silicon nanoparticles at a first temperature, and converting the amorphous carbon shell to a graphite carbon shell at a second temperature higher than the first temperature. The method can optionally include producing silicon nanoparticles by providing an argon-silane mixture, exposing the argon-silane mixture to a non-thermal plasma to convert the silane mixture to amorphous clusters, and passing the amorphous clusters through a furnace at a first temperature so as to agglomerate them to silicon nanoparticles.

Polycrystalline diamond and method for manufacturing same, scribe tool, scribe wheel, dresser, rotating tool, orifice for water jet, wire drawing die, cutting tool, electrode, and processing method using polycrystalline diamond

Provided is polycrystalline diamond having a diamond single phase as basic composition, in which the polycrystalline diamond includes a plurality of crystal grains and contains boron, at least either of nitrogen and silicon, and a remainder including carbon and trace impurities; the boron is dispersed in the crystal grains at an atomic level, and greater than or equal to 90 atomic % of the boron is present in an isolated substitutional type; the nitrogen and the silicon are present in an isolated substitutional type or an interstitial type in the crystal grains; each of the crystal grains has a grain size of less than or equal to 500 nm; and the polycrystalline diamond has a surface covered with a protective film.

Polycrystalline diamond and method for manufacturing same, scribe tool, scribe wheel, dresser, rotating tool, orifice for water jet, wire drawing die, cutting tool, electrode, and processing method using polycrystalline diamond

Provided is polycrystalline diamond having a diamond single phase as basic composition, in which the polycrystalline diamond includes a plurality of crystal grains and contains boron, at least either of nitrogen and silicon, and a remainder including carbon and trace impurities; the boron is dispersed in the crystal grains at an atomic level, and greater than or equal to 90 atomic % of the boron is present in an isolated substitutional type; the nitrogen and the silicon are present in an isolated substitutional type or an interstitial type in the crystal grains; each of the crystal grains has a grain size of less than or equal to 500 nm; and the polycrystalline diamond has a surface covered with a protective film.

Dendritic materials with hierarchical porosity

Disclosed herein are dendritically porous three-dimensional structures, including hierarchical dendritically porous three-dimensional structures. The structures include metal foams and graphite structures, and are useful in energy storage devices as well as chemical catalysis.

Dendritic materials with hierarchical porosity

Disclosed herein are dendritically porous three-dimensional structures, including hierarchical dendritically porous three-dimensional structures. The structures include metal foams and graphite structures, and are useful in energy storage devices as well as chemical catalysis.