158results about How to "Improve the degree of graphitization" patented technology

The invention relates to a carbon ceramic braking pad for a high-speed train and a preparation method of the carbon ceramic braking pad. The carbon ceramic braking pad is made of carbon ceramic composite material; the carbon ceramic composite material comprises the following components in percentage by mass: 16-30 percent of carbon fibers, 20-36 percent of pyrolytic carbon, 28-46 percent of silicon carbide, 6-12 percent of molybdenum disilicide and 2-6 percent of simple substance silicon; the density of the carbon ceramic composite material is 1.8-2.4g/cm<3>; the carbon fibers are uniformly distributed in the carbon ceramic composite material in a three-dimensional network structure. According to the invention, after the high-temperature heat treatment is performed on a carbon fiber felt with the density of 0.20-0.65g/cm<3>, the pyrolytic carbon is generated in the carbon fiber felt through the thermal-gradient chemical vapor deposition carburizing treatment, then the catalytic graphitization treatment, non-immersion type melting infiltration and assembly are performed, so that the carbon ceramic braking pad for the high-speed train is obtained.The carbon ceramic braking pad is simple in preparation technology, moderate in friction coefficient, good in abrasion performance, stable in braking and strong in environmental suitability and can meet braking requirements of the high-speed train with the speed of 200Km/h.

The invention discloses a making method of narrow-aperture high-graphitizing degree middle-hole carbon, which comprises the following steps: allocating metal compound and carbon primer with weight rate at 0.1-6:1; dissolving metal compound in the solution with carbon primer; stripping solvent; solidifying in the air for 0.1-20h under 80-400 deg.c; charring for 0.1-3h under inert gas at 500-1200 deg.c; proceeding acid washing until the metal element is not detected; obtaining the product.

The invention relates to a fuel battery catalyst, and in particular relates to application of a carbon gel catalyst in a fuel battery. According to the invention, the precursor components of the catalyst consist of resorcinol, formaldehyde and a metal salt, wherein the metal salt comprises soluble nitrates, carbonates, sulfates, acetates or halides of one or more metal elements in IVB, VB, VIB, VIIB, VIII, IB and IIB groups; in the precursor, the molar ratio of resorcinol to formaldehyde is 2:1, and the molar ratio of resorcinol to the metal salt is (5:1)-(1500:1); and the precursor is mixed with organic gel and then carbonized and nitrogenized at the ammonia environment of 500-1200 DEG C so as to prepare the high-activity carbon gel catalyst. According to the invention, as a non-metal catalyst, the carbon gel catalyst shows good oxygen reduction activity and good electrochemical stability when being used as a fuel battery negative electrode catalyst.

The invention relates to a preparation method of a C/C (carbon/carbon) composite material slider for a pantograph, and belongs to the technical field of preparation of materials for electric locomotives. The preparation method comprises the following steps of: according to the weight ratio of carbon cloth and carbon felt of (7.5-9): (3-1), circularly overlapping single layer 0-degree weft-free carbon cloth, carbon fiber web tire, 90-degree weft-free carbon cloth and carbon fiber web tire sequentially, and introducing carbon fiber bundles in the direction vertical to the spread by a relay type acupuncture method to form a 2.5D carbon fiber acupuncture integrated felt with density of 0.3-0.6g/cm<3>; performing high-temperature pre-treatment at 1500-2100 degrees centigrade, and performing chemical vapor deposition pyrolytic carbon treatment until obtaining the C/C composite material with the density of 1.4-1.6g/cm<3>; machining according to predetermined size, performing polymer dipping-carbonizing treatment and graphitization treatment sequentially, and then machining according to designed size, so as to obtain a product. The process is simple, a product has excellent mechanical and electrical properties, and the industrial application is prompted.

The invention relates to a carbon carrier of a proton exchange membrane fuel cell, in particular to a preparation method for carbon dry gel. The carbon dry gel is prepared by m-dihydroxybenzene, formaldehyde and a metal salt serving as raw materials, wherein the metal salt comprises a soluble nitrate, a carbonate, a sulfate, an acetate or a halide of one or more metal elements in an IVB group, a VB group, a VIB group, a VIIB group, a VIII group, an IB group and an IIB group; the m-dihydroxybenzene serving as a precursor and the formaldehyde are in the mol ratio of 2:1; the m-dihydroxybenzene and the metal salt are in the mol ratio of 10:1-500:1; and a high-stability carbon carrier is prepared by graphitizing mixed organic carbon dry gel at the high temperature of 1,500 to 3,500 DEG C. When serving as an anti-corrosion carbon material and being used as a cathode catalyst carrier of the proton exchange membrane fuel cell, the carbon dry gel has high anti-corrosion performance and high stability in an acidic and high-potential environment of cell operation.

The invention relates to a preparation method of a synthetic graphite negative electrode material for a lithium ion battery. According to the method, nonmetal carbide is taken as a raw material and subjected to once high temperature decomposition or twice high temperature decomposition to prepare synthetic graphite, which belongs to the field of the lithium ion battery. The synthetic graphite negative electrode material for the lithium ion battery, provided by the invention, has high degree of graphitization, high compaction density, excellent electrochemical performance, higher specific capacity of lithium removal in the range of 360-365mAh/g, primary coulombic efficiency of 83%-90% and capacity retention ratio of more than 98.3% within 15 weeks, and is suitable for the volume type lithium ion battery, simple in production flow and easy for industrialization.

The invention belongs to the technical field of a lithium ion battery negative electrode material, and particularly discloses an artificial graphite negative electrode material with a gradient structure. The artificial graphite negative electrode material is a carbon material with a core/shell structure, and the graphitization degree and the porosity of the carbon material are in gradient distribution in a radial direction; and from core to shell, the graphitization degree is gradually reduced, and the porosity is gradually reduced. The invention also provides the artificial graphite negativeelectrode material with the gradient structure. By pore-forming, catalyst carrying and two-segment electro-forging on anthracite, the negative electrode material with the graphitized and porosity dual-gradient structure can be prepared; and the material with the gradient structure is compatible with the advantages of high reversible capacity, high rate performance, long cycle lifetime and the like.

The invention belongs to the field of preparation processes of lithium batteries and particularly relates to a negative pole material for a lithium ion power and energy storage battery, as well as a preparation method and a battery thereof. Based on the insufficiencies in modification of the negative pole material in the prior art, a mixed solution of a binder and a catalyst is firstly configured, and graphite-like materials with different structures are uniformly mixed to form a graphite mixed body with different graphite structure types and close combination; then a porous coated carbon material is prepared by Friedel-Crafts cross-linking reaction, and coating, carbonization, crushing and other treatment are performed on the graphite mixed body, thus the negative pole material with high compaction density, strong liquid absorption capability, excellent rate performance and good cycling performance is finally prepared.

The invention discloses a high thermal conductivity and high microporous electrically calcined coal based carbon brick and a preparation method thereof. The technical scheme includes: conducting presintering in reducing atmosphere in an atmosphere furnace successively to obtain activated electrically calcined anthracite particles and activated electrically calcined anthracite fine powder; mixing nickel nitrate hexahydrate with anhydrous ethanol to obtain a nickel nitrate solution; taking 10-20wt% of activated electrically calcined anthracite fine powder, 4-10wt% of alpha-Al2O3 micropowder, 4-10wt% of silicon powder, 2-6wt% of aluminum magnesium alloy powder, 1-2wt% of carbon black and 0.5-1wt% of boron carbide powder as the matrix, and using 60-70wt% of activated electrically calcined anthracite particles as the aggregate; firstly putting the aggregate and a nickel nitrate solution into a mixing mill, performing mixing, then adding thermosetting phenolic resin, and conducting mixing milling, then adding the matrix blended matrix fine powder, and carrying out mixing milling, molding and drying; and finally performing firing in nitrogen atmosphere and under a 1080-1280DEG C condition, thus obtaining the high thermal conductivity and high microporous electrically calcined coal based carbon brick. The product prepared by the method provided by the invention has the characteristics of high thermal conductivity, high micropore ratio and good resistance to molten iron erosion.

The invention discloses a blocky graphite negative electrode material for a lithium ion battery, a preparation method of the blocky graphite negative electrode material and the lithium ion battery. The negative electrode material comprises a blocky graphite matrix, wherein the surface of the blocky graphite matrix is coated with a graphite coating layer. According to the blocky graphite negative electrode material for the lithium ion battery, a great number of micro-holes are formed in the surface of the blocky graphite matrix, and the graphite coating layer is highly combined with the coated blocky graphite matrix, so that the blocky graphite negative electrode material has the advantages of high intermolecular binding force, high tap density, high reversible specific capacity and good rate performance, a negative electrode sheet prepared by using the blocky graphite negative electrode material is slightly bounced and expanded, and the prepared lithium ion battery has excellent electrochemical performance. According to the blocky graphite negative electrode material, the purpose of blocky graphite is expanded, the additional value of a natural graphite product is increased, and the development space of a negative electrode material source of the lithium ion battery is enlarged; the negative electrode material can be used as the negative electrode material of an aluminum shell lithium ion battery, a flexibly package lithium ion battery, a cylindrical lithium ion battery and other lithium ion batteries; the blocky graphite negative electrode material has a wide application prospect.

The invention discloses a determination method of a large-size high-heat conduction graphite membrane. The method comprises carrying out cutting to obtain a PI membrane with the diameter of 40mm, overlapping the 80 PI membranes, putting them into a carbonization furnace, carrying out carbonization, carrying out mechanical pressurization at pressure intensity of 200kg/cm<2>, taking a sample and carrying out heat treatment, wherein in the heat treatment, a microstructure conversion process is divided into four phases, the first phase temperature is less than 800 DEG C, a second phase temperature is in a range of 800-2000 DEG C, a third phase temperature is in a range of 2000-2500 DEG C and a forth phase temperature is greater than 2500 DEG C. The PI membrane-to-graphite conversion process is divided into the four phases. In the whole reaction process, the product has original membrane molecular orientation and high plane orientation. The sample has a graphitization degree of 74.4% and thermal conductivity of 850W/(m.K) to 1000W/(m.K).

The invention discloses a method for improving the graphitization of a carbon material and the carburization degree based on a magnetic field and the catalysis. The method aims to apply the magnetic field induction and control the structural orientation of a newly generated graphite layer to ensure that the carbon material grows according to the preset orientation, thereby achieving the aim of improving the electromechanical properties of the carbon material. A proper amount of ferromagnetic catalyst is added into the carbon material, and then the high temperature carbonization and graphitization treatment is performed under the action of an externally-applied magnetic field; and the graphitization based on the carbon material is performed on the surface of the catalyst, and the ferromagnetic catalyst can directionally move on a molten carbon matrix under the action of the magnetic field to ensure that the graphitization is performed according to the direction of the magnetic field, thereby achieving the aim of controlling and affecting the structural orientation of the newly generated graphite layer to produce the carbon material with high orientation degree and high graphitization degree, and playing an active role in the increase and improvement of the electromechanical properties of the carbon material.

A provided graphitization processing method for soft coal and coal-rock compositions thereof comprises the following steps: step 1, crushing soft coal into a coal powder; or firstly employing a manual peeling method to obtain coal-rock compositions from soft coal, and then crushing coal-rock compositions, so as to obtain a coal powder; step 2, performing de-ashing processing; step 3, uniformly mixing the coal powder with a catalyst to obtain a mixed powder; and step 4, performing graphitization processing, so as to obtain a graphitized product with the graphitization degree of 75% or more. According to the method, soft coal or coal-rock compositions peeled from soft coal are taken as the raw material, the influence of the catalyst iron chloride or boric acid on high-temperature graphitization of soft coal or coal-rock compositions thereof is investigated, graphitization of soft coal or coal-rock compositions thereof is realized, a new technology for employing soft coal to prepare ultrafine graphite powder is exploited, a new approach is developed for utilization of high added value of soft coal, and a new carbon raw-material source is developed for graphite materials.

The invention provides a prebaked anode for aluminum electrolysis and a production process thereof, which belong to the field of carbon products. The prebaked anode for aluminum electrolysis is prepared from the following raw materials according to weight percent: 82 to 86% of preparation components and 14% to 18% of adhesives, wherein the preparation components include 80% to 84% of calcined petroleum coke, 14% to 16% of anode scraps and 2% to 4% of cathode milling flour according to weight percent. The production process comprises the steps of preparing the raw materials of the prebaked anode for aluminum electrolysis, mixing the preparation components at the first stage, adding the adhesives, mixing at the second stage so as to prepare thickeners, performing vibration forming on the thickeners so as to obtain anode green bodies, performing water-cooling curing on the anode green bodies, and then roasting and cooling. According to the production process, the resistivity of the prebaked anode for aluminum electrolysis can be reduced, and the conductivity of a carbon anode can be increased, so that a prebaked anode product with low resistivity is obtained, and the consumption of electrolysis for producing electric energy is reduced.

The invention discloses a method for preparing high thermal conductivity graphite through catalytic graphitization. The method comprises the following steps: (1), preparing a carbon film material with an amorphous carbon structure by performing carbonization treatment on a polyimide film; (2), loading a catalyst onto the surface of the carbon film material obtained in the first step through any one method of solution impregnation, electroplating, chemical plating and liquid-phase precipitation; (3), performing graphitization treatment on the carbon film material, with the surface being loaded with the catalyst, obtained in the second step, so as to obtain the high thermal conductivity graphite. According to the method, a PI film is carbonized, so as to obtain the carbon film with the amorphous carbon structure, and then the catalyst is loaded onto the carbon film formed after carbonization, so that the catalyst is subjected to contact reaction with the film with the amorphous carbon structure from the outer part to the inner part, and damage caused by the overflow of the catalyst from the inner part is avoided. A graphite film prepared through the method can obtain high graphitization degree, excellent thermal conductivity and good bending resistance in low graphitization temperature.

The invention provides a method for preparing mesophase carbon microspheres with an emulsification-hydrogenation-thermal polymerization ternary coupled system and belongs to the technical field of preparation of mesophase carbon microspheres. The method comprises steps as follows: 1) an emulsification-hydrogenation-thermal polymerization ternary coupled solvent system is prepared from a hydrogen supply solvent, a modification catalyst and an emulsification solvent; 2) medium and low temperature coal tar asphalt with the fraction larger than 300 DEG C is added to the emulsification-hydrogenation-thermal polymerization ternary coupled solvent system, and mesophase asphalt is prepared; 3) the mesophase asphalt is subjected to extraction with an organic solvent, dried, pre-oxidized in the airatmosphere, carbonized in an N2 atmosphere and graphitized, and mesophase carbon microspheres are obtained. The preparation method of the mesophase carbon microspheres is a brand-new one-pot emulsification system, a good production environment is provided for growth of the mesophase carbon microspheres, and good sphericity degree, smooth surfaces, uniform size distribution and high graphitizationdegree of the prepared mesophase carbon microspheres are guaranteed.

The present invention discloses porous graphene and a preparation method therefor. The preparation method comprises the following steps: adding a graphite raw material into an acetic acid solution of chitosan; and by taking chitosan as a peeling agent, carrying out ultrasonic treatment and centrifugal purification to prepare the porous graphene material. The graphene material not only has a porous structure, but also is relatively few in number of layers, and the transverse size of the flaky layer is relatively large. Compared to the prior art, as only ultrasonic treatment is carried out, the preparation method is simple and easy to implement; as the graphite is taken as the raw material, the prepared porous graphene material is high in degree of graphitization. The porous graphene material has a huge application value in the fields of absorption, catalysis, gas separation, super capacitors and the like.

The invention relates to application of a rare-earth compound in graphitization and a method for graphitizing a resin carbon material. The application lies in that a rare-earth oxide is used as a catalyst; and a carbon material taking resin as a carbon source is catalyzed and graphitized. The method comprises: using the resin as the carbon source; selecting the rare-earth compound as a catalyst raw material; converting the rare-earth compound into a catalyst rare-earth oxide in the process of resin carbonization; and carrying out the reaction process in a graphitizing furnace in the atmosphere of argon gas, wherein the temperature of heat treatment is not less than 2,000 DEG C.

The invention provides a method for coating graphite, which comprises the steps of: grinding a coating material into powder at a temperature of -160-0 DEG C, mixing with graphite powder (or adding a catalyst), and carbonizing and graphitizing to prepare the coating graphite material. A carbonizing container is made of the graphite or a graphite sheet is additionally arranged on powder body in the traditional carbonizing container. The coating material has low size distribution value, small powder particles and good coating effect, can effectively improve the graphitization degree of the coating graphite material, and reduce the specific surface area to improve the material performance.