679results about "Silicon carbide" patented technology

The invention discloses a method for converting a waste wind power blade composite material into silicon carbide, which comprises the following steps: mixing waste wind power blade composite material powder with a conductive agent to obtain a mixture, the waste wind power blade composite material comprising a silicon element and a carbon element; and performing flash Joule heat treatment on the mixture to obtain the silicon carbide. According to the method, the waste wind power blade composite material powder does not need to be subjected to any pretreatment such as pyrolysis, the waste wind power blade composite material can be converted into the silicon carbide with the high additional value only through one-step flash Joule heat treatment in the presence of the conductive agent, and the process steps are simple; and meanwhile, the flash Joule heat treatment is an electric heating pulse rapid high-temperature treatment mode, so that the time consumption is very short, and the method is energy-saving, efficient and environment-friendly.

Ultrafast Joule heating synthesis methods and systems, and, more particularly, ultrafast flash Joule heating upcycling from fiber-reinforced plastics (such as waste fiber-reinforced plastic, glass fiber-reinforced plastic, carbon fiber-reinforced plastic, and / or quartz fiber-reinforced plastic) and materials that include fiber-reinforced plastics (such as reinforced metal laminates including glass reinforced aluminum laminates and other glass reinforced metal laminates) to phase-controllable silicon carbide (SiC). Further, ultrafast Joule heating synthesis methods and systems to synthesize include SiC fibers / fibrils (such as SiC nanowires), SiC nanowires and SiC in polymer composites, and B4C nanowires.

The present invention refers to a method for the production of SiC. The method at least comprises the steps: Providing a vent gas mixture (2400), wherein the vent gas mixture (2400) is preferably generated during SiC production and highly preferably generated during CVD SiC production, wherein at least one fraction of the vent gas mixture is HCI and / or STC, wherein further fractions (2401) of the vent gas mixture (2400) at least comprise H2 (2402) and a C-bearing-molecule, in particular methane, (2404), Generating Chlorosilanes (2394) by reacting the at least one fraction of the vent gas mixture and Si (2398), Forwarding at least the generated Chlorosilanes (2394) into a process chamber (856a) of the CVD SiC production reactor (850a), and Forwarding at least one C-bearing molecule into the CVD SiC production reactor (850a), Producing SiC inside the process chamber (856a) of the CVD SiC production reactor (850a) by depositing Si from the Chlorosilanes and C from the at least one C-bearing molecule on at least one deposition surface or Forwarding at least the generated Chlorosilanes (2394) into a process chamber (856b) of a further CVD SiC production reactor (850b), and Forwarding at least one C-bearing molecule into the further CVD SiC productio reactor (850b), Producing SiC inside the process chamber (856) of the further CVD SiC production reactor (850b) by depositing Si from the Chlorosilanes and C from the at least one C- bearing molecule on at least one deposition surface.

An anode for a secondary battery is provided, the anode for a secondary battery including: an anode current collector; a first anode mixture layer formed on at least one surface of the anode current collector, and including a first silicon-based active material and a first conductive material; and a second anode mixture layer formed on the first anode mixture layer, and including a second silicon-based active material and a second conductive material, wherein a content of the first silicon-based active material in the first anode mixture layer is lower than a content of the second silicon-based active material in the second anode mixture layer, and a Radial Breathing Mode (RBM) peak is observed in a Raman spectrum obtained from a surface of the second anode mixture layer.

The invention discloses a method for preparing silicon carbide materials by using coal gasification slag, belonging to the field of solid waste recycling. The solution of the invention includes first pre-treating the coal gasification slag, then performing acid leaching, water washing, suction filtration and drying on the pre-treated coal gasification slag, and then performing Joule heating treatment. After calcination, silicon carbide is obtained; in the Joule heating treatment, the discharge voltage is set to 120V-150V, and the number of discharges is 1-5 times. By performing Joule heating treatment on the coal gasification slag, the reaction time of each Joule heating reaction is extremely short, greatly reducing the energy consumption, and sharply shortening the reaction time, solving the technical problem of high energy consumption caused by the long reaction time in the traditional carbothermal reduction for preparing silicon carbide materials in the prior art.

The present invention refers to a SiC and Chlorosilane production system 2540, comprising at least one CVD SiC production reactor 850, in particular SiC fluidized bed reactor 850a, in particular according to claim 9, and a Chlorosilane production unit 2550, wherein the Chlorosilane production unit 2550 comprises at least a bed reactor 2416, in particular a fixed bed reactor or a fluidized bed reactor, for generating Chlorosilanes by reacting at least one fraction of the vent gas mixture provided via the vent gas outlet 216 of the CVD SiC production reactor 850 and Si, wherein further fractions of the vent gas mixture at least comprise H2 and a C-bearing molecule, in particular methane, and wherein Si is provided as solid 2398 inside the bed reactor 2416.

The composite negative electrode material and its preparation method and application belong to the field of battery technology. A composite negative electrode material comprising a core containing a porous carbon material and Si particles, and a coating layer located on at least a part of the surface of the core, the Si particles being distributed on the surface and / or in the pores of the porous carbon material, the composite negative electrode material comprising micropores and mesopores, the ratio of the pore volume of the micropores to the pore volume of the mesopores being 2:98 to 50:50, the oil absorption value of the composite negative electrode material being smaller than that of the composite negative electrode material after the Si particles have been removed, and the difference value when the oil absorption value of the composite negative electrode material after the Si particles have been removed is taken as 100% is ≧10%. In the composite negative electrode material, the porous properties of the porous carbon provide a space for the volume expansion of Si, and the use of porous carbon having a certain strength as a skeleton further ensures the stability of the entire composite negative electrode material, and improves the cycle performance of the composite negative electrode material.

Belonging to the technical field of high temperature resistant composite aerogel, the invention provides a bicontinuous network composite aerogel with large length-diameter ratio shell-core structure in-situ embedded porous silicon carbide foam, which comprises a shell-core structure and a skeleton, the shell-core structure comprises an inner core and a shell layer, the shell layer is of a ceramic silicone rubber layer structure, and the inner core is a SiC nanowire of a continuous network structure; the framework is porous silicon carbide foam with a continuous network structure; wherein the core-shell structure is embedded on the skeleton structure in situ to form an interspersed bicontinuous network composite structure. The invention also provides a preparation method, according to the method, by precisely designing the mechanical distribution of the nanowires, the ceramic skeleton and the porous structure on the coupling characteristic, the multifunctionality, energy absorption and high temperature resistance of the composite aerogel are synergistically optimized, and the composite aerogel has remarkable advantages in the aspects of regulation and control of sound waves, electromagnetic waves and light waves, high-temperature oxidation resistance and vibration resistance. Therefore, the composite material has wide application potential in the fields of aerospace, military protection, electronic equipment, building shock insulation and the like.

The present invention relates to a composite powder for use in a negative electrode of a battery, the composite powder comprising composite particles and carbon nanotubes, the composite particles comprising a carbonaceous matrix material in which silicon-based particles are embedded, and wherein the surfaces of the composite particles are at least partially covered by the carbon nanotubes.

The invention provides a preparation method of a high-thermal-conductivity silicon carbide particle reinforced aluminum-based composite material. The preparation method comprises the following steps: step 1, shaping silicon carbide particles; step 2, mechanical mixing; step 3, packaging; step 4, carrying out vacuum hot degassing; and fifthly, hot isostatic pressing treatment is conducted, specifically, the ingot blank is put into a hot isostatic pressing machine to be subjected to hot isostatic pressing, then an aluminum sheath of the ingot blank is removed through machining, and the high-thermal-conductivity silicon carbide particle reinforced aluminum-based composite material is obtained. According to the preparation method of the high-thermal-conductivity silicon carbide particle reinforced aluminum-based composite material, the preparation process of the high-thermal-conductivity aluminum-based composite material can be optimized, the specific surface area of particles is reduced, the bonding interface area of the composite material is reduced, and the thermal resistance of the composite material is reduced; the heat-conducting property of the composite material is improved; and the stress around the silicon carbide particles can be more uniform, and the mechanical property is better.

Ultrafast flash evaporation joule heating synthesis methods and systems, more particularly, ultrafast synthesis methods for recovering metals from ores, fly ash, and bauxite residue (red mud).

A process and an apparatus for silicon carbide production includes steps of producing a mixture having at least a carbon powder and a silica powder where the percentage by weight of carbon powder with respect to the total weight of the mixture, is at least about 25%; placing the mixture in a crucible; creating a substantially inert atmosphere in an area at least partially surrounding the crucible; heating up the crucible by a heating device for a first time interval until reaching a working temperature of at least 1.500° C. and lower than a melting temperature of the silica powder in the mixture; maintaining the crucible within a working temperature range between 1.500° C. and the melting temperature of the silica powder in the mixture for a second time interval; and reducing the temperature of the crucible after the second time interval.

The invention provides a copper-doped silicon carbide composite material and a preparation method and application thereof, and relates to the technical field of electromagnetic wave absorbing materials. The preparation method of the copper-doped silicon carbide composite material provided by the invention comprises the following steps: performing arc plasma cracking on a precursor containing silicon and carbon to obtain the copper-doped silicon carbide composite material, the precursor containing silicon and carbon comprises organic chlorosilane; an anode adopted by the arc plasma cracking comprises copper. The prepared copper-doped silicon carbide composite material has excellent electromagnetic wave absorption performance and large effective absorption bandwidth.

A method for producing high-purity silicon carbide powder includes filling starch-based packing chips or expanded starch as organic raw material into a container open at the top; introducing the container filled with the raw material into a furnace and heating the packing chips, or the expanded starch, gradually to a temperature of 2,000° C. whilst feeding inert gas or under vacuum to graphitize the packing chips or the expanded starch into porous graphite pieces; feeding halogen gas, such as chlorine or fluorine, into the furnace to purify the porous graphite pieces at a temperature of >1,800° C. to remove foreign metals from the porous graphite pieces by forming metal chloride, and converting the porous graphite pieces into powdered silicon carbide by feeding SiO with argon as carrier gas at a temperature of >1,200° C. at a pressure of 30 mbar or higher.

The present application provides a kind of silicon-carbon negative electrode material and its preparation method.The silicon-carbon negative electrode material includes carbon skeleton with pore structure and silicon-based material arranged in the pore structure, in the region from the surface of the silicon-carbon negative electrode material to the inside extending 10nm from the surface, the content of high-valence silicon is less than 25% relative to the total amount of low-valence silicon and high-valence silicon, wherein the low-valence silicon is 0-valence to 2-valence silicon, and the high-valence silicon is 3-valence to 4-valence silicon.Thereby, the lithium extraction gram capacity and the first coulomb efficiency of the silicon-carbon negative electrode material can be improved, and the discharge gram capacity and the first coulomb efficiency of the secondary battery can be improved.

The invention discloses a double-layer nano silicon-based material as well as a preparation method and application thereof, and belongs to the technical field of energy storage. The double-layer nano silicon-based material sequentially comprises a core layer, a first shell layer and a second shell layer from inside to outside, the core layer is nano silicon, the first shell layer is a silicon carbide layer with the thickness of 1.1-5.0 nm, and the second shell layer is a carbon layer with the thickness of 1.1-4.2 nm; a carbon-silicon bond is formed between the core layer and the first shell layer, and a carbon-silicon bond is formed between the first shell layer and the second shell layer. On one hand, silicon volume expansion is physically limited through a high-strength rigid framework; on the other hand, an ion / electron synergistic conduction functional interface layer is constructed, and unification of stress buffering, interface stability and rapid dynamics is achieved.

An industrial furnace system, particularly for producing ceramic materials and / or carbides, includes at least one furnace with a chamber having a loading opening for loading the chamber, a heating device and a closure device for the opening, a control device and a transfer device for transferring a crucible that can be placed in the chamber to and / or from the furnace. To remove the crucible from the chamber, the control device is configured to bring the closure device—by actuating the transfer device and / or depending on the position of the transfer device and / or an end effector thereof—into the release position and / or to allow for a crucible to be removed through the opening when the closure device is in the release position by actuating the transfer device and / or preferably depending on the transfer device and / or end effector position by actuating a removal device separate from the transfer device.

The invention discloses a reaction device for cleaning the surface of a silicon carbide ring, and relates to the technical field of polycrystalline silicon production. Comprising a reaction assembly, the reaction assembly comprises a tank body and further comprises a lifting assembly, the lifting assembly comprises an annular block and a mounting plate, the annular block is rotatably arranged in the tank body, an annular gear is fixed below the annular block, the mounting plate is fixed in the tank body, and a plurality of threaded rods are rotatably arranged between the mounting plate and the bottom of the tank body; driven gears are fixed to the ends of the multiple threaded rods, a lifting motor is fixed to the bottom of the tank body, an output shaft of the lifting motor is connected with the threaded rods through couplings, a lifting circular plate is connected to the multiple threaded rods in a threaded mode, a placing assembly is arranged on the lifting circular plate, a circulating assembly is arranged in the tank body, and a plurality of rotating assemblies are arranged above the tank body; the contact area with the circular ring plate can be reduced, meanwhile, the rubber block can drive the silicon carbide ring to rotate, the contact part is prevented from being blocked, and the cleaning efficiency of the silicon carbide ring is improved.

The utility model provides a silicon carbide powder pickling device, which relates to the field of silicon carbide processing, and comprises a plurality of supporting legs, the outer surface of each supporting leg is fixedly connected with a first bracket, and the equipment comprises a transmission system consisting of a first motor, a transmission rod, a rotating disc, a rotating rod, a push-pull rod, a limiting bracket, a transmission arm and the like. Complex and accurate relative movement of the first bulkhead and the second bulkhead is achieved, compared with existing equipment, the transmission design can more effectively break the agglomeration phenomenon of powder in the acid pickling process, it is ensured that each powder can be fully exposed in acid liquor, the uniformity and thoroughness of acid pickling are greatly improved, and the production efficiency is improved. By means of the synergistic effect, the powder and the acid liquor can be more fully mixed within a shorter time, the pickling reaction process is accelerated, the pickling efficiency is remarkably improved, the powder can be promoted to rapidly pass through the screen through the motion modes of swinging, vibration and the like of the partition frame, and the period of the whole pickling technological process is greatly shortened.

The invention provides a silicon carbide-coated silicon-based negative electrode material, a silicon carbide negative electrode material and a preparation method thereof, a secondary battery and electric equipment, and relates to the field of batteries. The preparation method of the silicon carbide coated silicon-based negative electrode material comprises the following steps: mixing a polymer and a silicon source, and then carrying out an oxidation-reduction reaction to obtain a precursor; and sintering the precursor to obtain the silicon carbide coated silicon-based negative electrode material, the temperature of the oxidation reduction reaction ranges from 1550 DEG C to 3000 DEG C. The preparation method of the silicon carbide negative electrode material comprises the step of carrying out etching treatment on the silicon carbide coated silicon-based negative electrode material by using an etching solution. According to the preparation method of the silicon carbide coated silicon-based negative electrode material provided by the invention, the product obtained through the high-temperature oxidation-reduction reaction is the spheroidized nano silicon, the product is sintered to enable the silicon surface to be uniformly coated with SiC, and finally the nano spherical silicon with the surface uniformly coated with SiC is obtained. The cycle performance of the silicon-based negative electrode with the structure is greatly improved.

A process for producing solar grade silicon from silica sand employs a plurality of plasma furnaces to perform a sequence of chemical reactions together with other process steps to produce solar grade silicon. The plasma furnace generates a stable dirty-air, donut-shaped plasma into which particulate matter can be introduced. The plasma in the first two stages is formed by gases from the chemical reactions and in the third from inert gasses. Cyclone separators are used to extract particulates from the plasma in an inert gas that prevents reverse reactions as the particulate cools.

Disclosed is an apparatus for the production of silicon carbide which comprises a heatable reactor (1) which has a feed opening (4) on its upper side for continuous feeding with a precursor (7), an outlet opening (5) on its lower side for the continuous exit of silicon carbide (10) formed in the reactor (1) from the precursor, and an internal space (3) between the feed opening (4) and the outlet opening (5), wherein the feed opening, outlet opening and internal space are arranged such that the precursor and silicon carbide can pass through the internal space (3) falling from the feed opening (4) to the outlet opening (5).

Organosilicon chemistry, polymer derived ceramic materials, and methods. Such materials and methods for making polysilocarb (SiOC) and Silicon Carbide (SiC) materials having 3-nines, 4-nines, 6-nines and greater purity. Processes for making SiC boules and SiC wafers utilizing such high purity SiOC and SiC.

The present invention belongs to the technical field of composite silicon-based negative electrode materials and discloses a composite silicon-based negative electrode material, a preparation method, and a solid-state battery. The composite silicon-based negative electrode material comprises a graphite substrate and silicon carbide nanowires and nanosilicon particles attached to the surface of the graphite substrate. The silicon carbide nanowires are interwoven to form a network structure, and the nanosilicon particles are dispersed in the network structure. The nanosilicon particles are dispersed in the network of interwoven silicon carbide nanowires, presenting a porous structure similar to that of reinforced concrete. The porous structure provides space for volume expansion, mitigating damage to the electrode structure caused by volume expansion during lithium insertion and extraction of the silicon-based negative electrode. At the same time, the one-dimensional silicon carbide therein, due to its high mechanical strength, can mitigate damage to the electrode structure caused by long-term cycling of the silicon negative electrode, thereby improving the mechanical properties of the silicon negative electrode and thus improving the cycling performance of the silicon electrode.

The invention belongs to the technical field of powder preparation, and relates to a preparation method of submicron 3C-SiC powder, which comprises the following steps: (1) mixing silicon powder, a carbon-containing raw material and a fluorine-containing raw material according to a certain proportion, fully ball-milling and uniformly mixing the powder and then drying, (2) putting the dried powder into an atmosphere furnace, introducing argon atmosphere, heating to 1400-1500 DEG C, preserving heat for 1-3 hours, and cooling to room temperature to obtain the submicron 3C-SiC powder. And (3) putting the reacted powder into a muffle furnace, and carrying out carbon removal treatment, so as to obtain the high-purity 3C-SiC powder. And the prepared powder is uniform in morphology and granularity and relatively high in purity. The method is simple, has low requirements on instruments and equipment, and is suitable for batch production. The 3C-SiC powder synthesized and prepared through the method is uniform in particle size (about 130 nm) and special in morphology, and a spherical structure is formed. The method is relatively simple in preparation process and convenient to operate, and lays a certain foundation for industrial production.

A silicon carbide ingot is provided, which includes a seed end, and a dome end opposite to the seed end. In the silicon carbide ingot, a ratio of the vanadium concentration to the nitrogen concentration at the seed end is in a range of 5:1 to 11:1, and a ratio of the vanadium concentration to the nitrogen concentration at the dome end is in a range of 2:1 to 11:1.

A method is disclosed comprising providing a carbonaceous substrate; performing a chemical vapor deposition process on the carbonaceous substrate using a mixture of precursor gasses comprising a silicon precursor gas comprising trichlorosilane, and a carbon precursor gas selected from carbon-carbon double bond hydrocarbons and carbon-carbon triple bond hydrocarbons; and via said chemical vapor deposition process, forming a polycrystalline cubic silicon carbide layer with crystallographic orientation.

A metal-doped silicon-carbon composite material and a preparation method therefor and a use thereof. The metal-doped silicon-carbon composite material comprises a core-shell structure composed of a core and a shell, wherein the core comprises metal and / or heteroatom-doped porous carbon and nano-silicon, the shell comprises lithium-doped amorphous carbon, and the weight percentage of the shell in the core-shell structure is not higher than 10 wt%.

The invention belongs to the technical field of preparation of high-temperature heat-insulating and electromagnetic wave-absorbing materials, and relates to a bamboo-like silicon carbide nanowire based on freeze-dried vegetables / fruits and a preparation method and application of the bamboo-like silicon carbide nanowire based on the freeze-dried vegetables / fruits, and the preparation method comprises the following steps: putting the vegetables / fruits in a freeze dryer to obtain the freeze-dried vegetables / fruits; putting the freeze-dried vegetables / fruits into a high-temperature tubular furnace for carbonization to obtain a carbon template; putting the carbon template and a silicon source into a graphite crucible, putting the graphite crucible into a high-temperature tubular furnace, and calcining to obtain the bamboo-like silicon carbide nanowire based on the freeze-dried vegetables / fruits. The bamboo-like silicon carbide nanowire prepared by the method has excellent high-temperature heat insulation property and remarkable broadband electromagnetic wave absorption property, so that the enhancement of double functions of heat insulation and wave absorption is synergistically realized on the basis of a single material. The preparation process is simple and stable in flow, good in repeatability, green in raw material and extremely low in cost, and the problems of collapse and atrophy of the material structure caused by high temperature are solved.

The present invention relates to a method for producing high-purity silicon carbide powder, by which high-purity silicon carbide powder can be produced economically and efficiently. This is achieved by: filling a starch-based packaging chip or expanded starch as an organic raw material into a container with an open top; placing the container filled with the raw material into a furnace, and gradually heating the packaging chip or expanded starch to a temperature of 2000°C, while adding an inert gas or graphitizing the packaging chip and expanded starch into a porous graphite sheet under vacuum; adding a halogen gas (such as chlorine or fluorine) to the furnace at a temperature of >1800°C to purify the porous graphite sheet to remove impurity metals from the porous graphite sheet by forming metal chlorides, and converting the porous graphite sheet into silicon carbide powder by adding SiO with argon as a carrier gas at a pressure of 30 mbar or higher at a temperature of >1200°C.