46results about How to "Improve carbonization yield" patented technology

The invention discloses a preparation method of polyacrylonitrile/graphene composite-based carbon fiber, which comprises the following steps: firstly preparing a polyacrylonitrile mixed solution uniformly dispersed with graphene through an in-situ polymerization method, and then employing the mixed solution as a spinning solution and obtaining a polyacrylonitrile/graphene composite protofilament by a wet spinning or dry-jet wet spinning process, and finally making the protofilament subject to a pre-oxidation treatment and a carbonization treatment to obtain the polyacrylonitrile/graphene composite-based carbon fiber. Compared with the existing polyacrylonitrile-based carbon fiber, the carbon fiber prepared by the method of the invention has a significantly increased mechanical property, and the carbonation yield in the preparation process is improved, therefore, the preparation method is an efficient and reliable preparation method with good application prospects.

A process for producing a spherical carbon material, comprising: subjecting a spherical vinyl resin to an oxidation treatment in an oxidizing gas atmosphere to obtain a spherical carbon precursor, and carbonizing the spherical carbon precursor at 1000-2000° C. in a non-oxidizing gas atmosphere. The thus-obtained spherical carbon material exhibits excellent performances, including high output performance and durability, when used, e.g., as a negative electrode material for non-aqueous electrolyte secondary batteries.

The present invention relates to preparation process of precursor fiber of cellulose base carbon fiber in chemical fiber production. The preparation process includes mixing concentrated NMMO aqua and carbon black for carbon black water in the weight ratio of 20-10000, decomprssion distillation to obtain NMMO/carbon black solution with water content 24-28 wt%, adding the mixtue of sliced cellulose pulp and NMMO/carbon black solution in the weight ratio of 5-15 to 100 into dissolving reactor, swelling and stirring at 70-90 deg.c, raising the temperature to 90-120 deg.c, stirring and decomprssion distillation to eliminate water and form cellulose/NMMO/carbon black spinning liquid with water content of 12-14 wt%, and dry-wet spinning to obtain the precursor fiber. The present invention has high carbonizing yield, high mechanical performance of the carbon fiber, raised spinnability of the spinning liquid, non-toxic solvent, high solvent recovering rate and environment friendship.

The invention belongs to the technical field of biomass heat conversion, and particularly relates to equipment and a process for carbonizing, activating, pyrolysis gasification, catalytic cracking of a plurality of product roads. The equipment comprises a flue pipe, an activator (gasifying agent) inlet, an auxiliary activator (gasifying agent) inlet, a feeding hole, a feeding cover seal, a forced blanking shoveling board, a gear, a drive and transmission case, heat-insulating cotton, a riding wheel, a barrel angle adjusting bolt, a temperature measuring device, a combustion channel, a product channel, an angle adjusting screw, a discharge cover seal, a lighting-up tuyere, an explosion-proof opening, a combustion-supporting opening (viewing port), a discharge sealing valve and a discharge cooler. According to the invention, the multifunctional biomass heat conversion equipment simultaneously has the functions of carbonizing, activating, pyrolysis gasification, catalytic cracking by changing an inclination angle, a rotating speed and a sealing mode; a traditional direct combustion method is changed into a bolometric method, and the problems of low yield, serious ignition loss, non-uniform reaction, small yield, large consumption and temperature control difficulty in the biomass heat conversion process are solved from the technical aspect.

The invention provides a preparation method for a three-dimensional hierarchical porous biomass carbon negative electrode material of a lithium ion battery. According to the invention, edible fungus is used as a raw material for biomass carbon and three-dimensional hierarchical porous biomass carbon is prepared through a combination of a microwave hydrothermal method and a heat treatment method; the three-dimensional hierarchical porous biomass carbon has good cycle stability and rate capability when used as the negative electrode material of the lithium ion battery; the edible fungus contains rich polysaccharides, so carbonization yield of biomass is high; a cell wall contains abundant chitin, so a stable carbon skeleton can be formed and enables the negative electrode material to have a stable structure and to be not prone to collapse during charging and discharging; and the pore size of the material can be controlled by controlling alkali concentration, so the electrochemical performance of the material is improved.

The invention relates to the technical field of sodium ion batteries, and provides a preparation method of a hard carbon material. The preparation method comprises the following steps: mixing a coal-based material and a hard carbon precursor, and pressing to obtain a hard sheet, wherein the hard carbon precursor is carbohydrate and/or gelatin; and carrying out high-temperature carbonization on theobtained hard sheet to obtain the hard carbon material. According to the invention, the hard carbon precursor and the coal-based material are in close contact through a tabletting means, so that thereaction activity of the hard carbon precursor and the coal-based material is greatly improved, the hard carbon precursor and the coal-based material are fully subjected to a cross-linking reaction ina high-temperature carbonization treatment process, the carbonization yield is effectively improved, meanwhile, defects formed in the carbonization process are reduced, the specific surface area is reduced, and the disorder of the carbon layers and the spacing between the carbon layers in the carbonization process are increased. A sodium ion battery obtained by taking the hard carbon material obtained by the preparation method as a negative electrode material of the sodium ion battery has high sodium storage capacity and first coulombic efficiency.

The invention discloses a method for preparing cellulose-based carbon fiber felt by low-temperature alkali urea method. The cellulose pulp is stirred at room temperature in a solvent composition of sodium hydroxide, urea, thiourea, water-soluble carbon black and water to prepare the felt. The cellulose suspension is obtained, and then enters the pre-frozen twin-screw extruder to obtain a black cellulose solution, which is finally filtered and defoamed and sprayed into a coagulation bath for spinning, and further washed, drawn, and oiled and drying to obtain cellulose fibers; the cellulose fibers are processed into cellulose fiber mats through a needle-punched non-woven process, and further catalyzed impregnation, pre-oxidation, and carbonization to obtain cellulose-based carbon fiber mats. The process of the invention is simple, the solvent used is green and environmentally friendly, the price is low, and the recovery rate is high. The spun cellulose fiber has a compact structure, good thermal stability, and ablation resistance. The processed cellulose-based carbon fiber felt is better than that without carbon black. Carbon fiber felt has a higher carbon yield.

The invention belongs to the technical field of carbon fiber application, and discloses a preparation method of carbon fiber paper. The preparation method comprises the following steps: carrying out surface treatment on chopped carbon fibers and chopped aramid fibers; with the carbon fibers, the aramid fibers and the pulp as raw materials, conducting dispersion and papermaking to prepare carbon fiber base paper; and adding a mesophase pitch fiber layer on the surface of carbon fiber base paper by adopting a melt-blowing method, carrying out oxidation-crosslinking on mesophase pitch fibers at 200-350 DEG C by adopting air as an oxidizing agent so as to obtain composite carbon fiber base paper when a precursor is not molten, dipping the composite carbon fiber base paper in a thermosetting phenolic resin ethanol solution, and successively carrying out hot pressing, curing, carbonization and graphitization to obtain the carbon fiber paper. By adding the aramid fibers, the structural uniformity and strength of the carbon fiber paper are effectively improved; the introduction of mesophase pitch enables the carbon fiber paper to have higher electric conductivity and thermal conductivity; and the prepared carbon fiber paper can meet the preparation requirements of high-performance fuel cells, high-temperature filtration and advanced composite materials.

The invention relates to the field of battery manufacturing and energy storage, in particular to a preparation method for an all-vanadium redox flow battery electrode material. The preparation method comprises the steps of taking alkaline lignin as a test material, partially substituting the hydroxymethylation alkaline lignin by a phenolic hydroxyl active functional group in an alkaline lignin structure, synthesizing organic gel from resorcinol and formaldehyde under the effect of a catalyst, preparing a precursor spinning liquid required for an experiment by taking the gel as a precursor, preparing a fiber precursor electrode material by an electrostatic spinning method, pre-oxidizing the electrode material precursor by a vacuum/atmosphere furnace, and performing carbonization in an inertia atmosphere to obtain the carbon fiber electrode material. In the vanadium battery carbon fiber electrode material prepared by the method, the fiber diameter is in nanoscale, and the specific area is greatly expanded compared with a traditional carbon felt electrode material; and due to pre-oxidization processing in post period, the oxygen content of the fiber surface is also greatly improved, and the method can be used for preparing the vanadium battery carbon fiber electrode material.

The invention discloses a template-free synthesis method of tannic acid-based porous polymers and derived carbon materials thereof under mild conditions. The template-free synthesis method of the tannic acid-based porous polymers and the derived carbon materials thereof under the mild conditions includes the steps of: (1) adding a compound containing a bisamino functional group, concentrated hydrochloric acid and deionized water to a round bottom flask, using an ice bath to control the temperature between 0-5 DEG C, and adding a sodium nitrite aqueous solution after stirring evenly and continuing stirring to completely convert amino groups into diazonium salt; (2) maintaining the ice bath state, adding a tannic acid and sodium carbonate aqueous solution after neutralizing with a sodium carbonate solution, conducting filtering separation of generated solid precipitate after 12 hours, washing with deionized water, methanol, tetrahydrofuran, methanol and water in sequence, and then conducting freeze drying to obtain the tannic acid-based porous polymers; (3) calcining the tannic acid-based porous polymers in a tube furnace at the temperature of 900 DEG C for 3 hours, and then coolingdown naturally to obtain target products. The template-free synthesis method of the tannic acid-based porous polymers and the derived carbon materials thereof under the mild conditions has the advantages of being simple, needing mild conditions and no template, and producing the final products that have excellent carbon dioxide capture capability.

The invention belongs to the technical field of porous carbon materials, and particularly relates to a preparation method of a nitrogen-doped porous carbon material and application of the nitrogen-doped porous carbon material in a supercapacitor. The nitrogen-doped porous carbon material is prepared by taking weathered coal humic acid as a carbon material precursor, urea as a nitrogen source and a potassium metal compound as an active agent through high-temperature reaction, and when the nitrogen-doped porous carbon material is applied to an electrode material of a supercapacitor, the supercapacitor shows excellent electrochemical performance. The initial raw materials are humic acid and urea which widely exist in nature and are low in price and rich in source, and the method only relates to a small number of procedures such as activation and cleaning, so that large-scale industrial production is easy to realize.

The invention discloses a novel biomass pyrolysis carbonization system and method, the novel biomass pyrolysis carbonization system comprises a pretreatment pool, a dryer, a crushing device, a granulation device, a carbonization device and a pyrolysis gas recovery device, the pyrolysis gas recovery device is connected with the carbonization device and a drying device. A first medicine adding device is connected to the pretreatment pool. The invention has the beneficial effects that pyrolysis gas generated in the biomass carbonization process passes through the heat energy recovery system and then is combusted again to heat the carbonization device and the drying device, the heat loss is reduced, the heat energy loss is reduced, the treatment cost is saved, and the biomass carbonization treatment system conforms to the cyclic utilization principle of resources.

The invention provides a preparation method of binder asphalt. The preparation method comprises the following steps: a, mixing a plurality of original tar raw materials into mixed coal tar, purifying the mixed coal tar, and carrying out an electrochemical oxidation reaction to obtain pretreated processed coal tar, wherein the quinoline insoluble content of the processed coal tar is 2% by mass or more and less than 20% by mass; b, distilling the processed coal tar to obtain medium-temperature pitch; c, carrying out thermal polymerization reaction on the medium-temperature pitch to obtain a polymer component; and d, evaporating low-molecular components in the polymer component to obtain the binder asphalt. The binder asphalt prepared by the preparation method has relatively low viscosity, and can fully wet aggregate coke when being applied to an electrode for aluminum smelting. A composite material formed by the binder asphalt and the aggregate coke is relatively high in stacking density and high in mechanical strength after being roasted. Thus, the resistivity of the electrode for aluminum smelting can be reduced, and consumption and cost in an aluminum smelting production process are reduced. The invention also relates to the binder asphalt and the aluminum smelting electrode.