1094 results about "Depolymerization" patented technology

The invention provides a bio-based adhesive and a preparation method thereof. Inspired by a spider thread structure, biomass adhesive interface enhancement based on a tannic acid adhesion group is combined with construction of a differential phase separation structure by biomass-induced polylipoic acid depolymerization, and a brand new strategy of adhesion-cohesion synergistic enhancement of the adhesive strength of the adhesive is realized. According to the invention, tannic acid and carboxymethyl chitosan are introduced into a lipoic acid-based adhesive, so that the purpose of synergistically enhancing the bonding performance of the adhesive through adhesion-cohesion is achieved, and the defects of weak cohesion, low bonding strength, poor water resistance, poor moisture resistance and the like of the conventional biomass adhesive are overcome. Benefited from a new strategy of adhesion-cohesion synergistic enhancement, the biomass adhesive has good adhesive strength in various environments and materials. In addition, the biomass adhesive also has the characteristics of biological safety, antibacterial and mildew-proof properties and recoverability, so that the product has wider application and potential compared with the previous product, and has a good application prospect.

The invention discloses a tightening and whitening composition containing EGCG (epigallocatechin gallate) as well as a preparation method and application of the tightening and whitening composition, and relates to the technical field of cosmetics. The invention provides a tightening and whitening composition containing EGCG (epigallocatechin gallate). The tightening and whitening composition is prepared from the following components in parts by weight: 0.1 to 2 parts of an epigallocatechin gallate nano composition, 0.05 to 0.5 part of a nucleic acid tetrahedron and 0.5 to 5 parts of glassine. When the EGCG nano composition, the nucleic acid tetrahedron and the glassine are cooperatively used, the stability of a formula can be improved, meanwhile, the EGCG can be accurately released to an epidermal layer due to the enzyme-responsive degradation characteristic (such as matrix metalloproteinase MMP-2 triggered depolymerization) of the nucleic acid tetrahedron, and the glassine is released after deeply penetrating into a corium layer along with a nucleic acid tetrahedron carrier, so that the EGCG can be accurately released to the epidermal layer. The synergistic effects of the three components on whitening and tightening are better exerted.

The invention provides high-filling silver powder and a preparation method thereof, and belongs to the field of metal powder.The preparation method comprises the steps that a nano-silver solution is prepared, a dispersing agent and a first reducing agent are mixed to obtain a mixed solution, the nano-silver solution and the mixed solution are mixed in a constant-temperature stirring state to obtain a base solution, a second reducing agent solution and a silver nitrate solution are prepared respectively, and the high-filling silver powder is prepared. And under the constant-temperature stirring state, the second reducing agent solution and the silver nitrate solution are synchronously added into the base solution, a silver powder solution is obtained through reaction, the silver powder solution is subjected to washing, solid-liquid separation, drying and depolymerization shaping treatment, and the high-filling silver powder is obtained. Controllable preparation of the large-size sphericity silver powder is achieved by controlling the particle size and the adding amount of the nano-silver, regulating and controlling heterogeneous nucleation and growth sites of silver ions and inhibiting formation of multistage dendritic crystals, surface charges and steric hindrance effects of silver particles are optimized through the surface adsorption effect of the dispersing agent, the agglomeration phenomenon of the silver powder in the growth process is reduced, and the silver powder is prepared. And meanwhile, the silver powder is endowed with excellent flowability.

The invention discloses an efficient purification method of rBHET, and belongs to the technical field of waste polyester recycling. A reaction raw material obtained after premixing of waste PET polyester raw material particles and a catalyst and ethylene glycol are jointly and continuously introduced into a depolymerization reactor, the reaction raw material and ethylene glycol in the depolymerization reactor are mixed and pass through a plurality of rotating discs, and the materials form a flowing film on the rotating discs rotating at a high speed to promote depolymerization; depolymerization reaction liquid generated in the depolymerization reactor enters a temporary storage tank to be stored after being subjected to impurity removal, the depolymerization reaction liquid in the storage tank is introduced into a rectifying tower to be primarily concentrated and purified, obtained concentrated liquid enters an evaporator to be secondarily concentrated and purified, obtained secondary concentrated liquid enters a cooler to be cooled and then enters a product tank to be crystallized; and drying the crystallized solid to obtain a high-purity rBHET product. According to the method, the production efficiency is improved, and the purity of rBHET is effectively improved.

This invention discloses a method for catalytically depolymerizing polyethylene terephthalate (PET) to prepare terephthalate. Under catalyst-free conditions or with a salt as a catalyst, PET or its composite system is treated in diester carbonate to achieve chemical depolymerization of PET, yielding PET monomers terephthalate and ethylene carbonate, and achieving complete depolymerization of PET in the composite. This invention, through the reaction of diester carbonate with PET, enables the depolymerization of PET under mild conditions, and further facilitates the research and development of related technologies for the chemical recovery of PET monomers from PET composite or mixed systems. The method provided by this invention has advantages such as high efficiency, environmental friendliness, and mild reaction conditions, and can catalyze the depolymerization of PET to generate its monomer terephthalate, possessing strong industrial application value.

The invention discloses a fan blade material processing device, which comprises a disintegration furnace, a splitting frame and a fiber claw, the furnace wall of the disintegration furnace is provided with a jet orifice, and the jet orifice is used for jetting a depolymerization liquid towards a blade falling in the disintegration furnace so as to depolymerize organic matters in the blade and separate fibers in the blade, the splitting frame is used for colliding falling blades so as to crush the blades; and the fiber claw is used for grabbing fibers in the depolymerization liquid when the discharging channel discharges the depolymerization liquid. According to the method, the problem of environmental pollution caused by garbage burying or incineration can be effectively reduced, fibers in the leaves can be effectively recycled, and the fibers can be reused in other industrial fields, so that resource waste is reduced. Compared with a traditional treatment method, the device can automatically carry out blade disintegration and fiber separation, the treatment efficiency is improved, the time for workers to make direct contact with waste is shortened, the risk for workers to make direct contact with waste is reduced, and therefore the health and safety of the workers are protected.

The invention belongs to the field of carbon nanomaterials, and provides a method for preparing a carbon quantum dot material doped with elements such as silicon and aluminum by oxidative depolymerization and stripping of coal gangue. Comprising the steps of screening and matching of coal gangue, oxidative depolymerization stripping, centrifugal dialysis membrane filtration and modification, drying and the like, raw materials and all the steps are specifically set, and the particle size or fluorescence performance of fluorescent carbon dots can be specifically selected and set according to selective oxidative depolymerization stripping conditions. The main particle size of the prepared multi-inorganic-element doped carbon quantum dot material is kept within the range of 1.5-2.0 nm, the structure is stable, the optical performance also meets the requirements, and the material can be further modified and is expected to be applied to the fields of photovoltaic equipment, biological imaging, photocatalytic degradation of organic pollutants or sensing and the like.

To provide a depolymerization method that allows efficient removal of a functional layer from a polyester film having a functional layer and enhances polyester recovery efficiency.SOLUTION: A depolymerization method of a polyester film comprising the following steps (I) to (IV): (I) depolymerizing a polyester film containing a functional layer to obtain a crude depolymerization solution A; (II) subjecting the obtained crude depolymerization solution A to specific gravity separation into a purified depolymerization solution X and a crude depolymerization solution B containing free matter; (III) separating free matter from the crude depolymerization solution B to obtain a purified depolymerization solution Y; and (IV) sending the purified depolymerization solution Y to a depolymerization tank.SELECTED DRAWING: Figure 1

The invention belongs to the technical field of emulsion materials, and particularly relates to metal-polyphenol network modified coconut protein composite particles as well as a preparation method and application thereof. The preparation method comprises the following steps: preparing a coconut protein-pectin compound by taking coconut protein and pectin as raw materials, adding a tannic acid solution into the coconut protein-pectin compound, mixing, adding a Fe < 3 + > solution, and mixing to obtain metal-polyphenol network modified coconut protein composite particles; according to the preparation method, tannic acid and the coconut protein-pectin compound are subjected to non-covalent interaction, Fe < 3 + > and phenolic hydroxyl groups on the tannic acid are subjected to coordination reaction, a metal-polyphenol network is formed through cross-linking of Fe-O coordination bonds, and a compact modification layer is constructed on the surface of the coconut protein-pectin compound, so that on one hand, waste coconut protein resources are utilized; on the other hand, the problem that composite particles prepared from pectin and coconut protein are prone to depolymerization is solved, the structural stability is improved, and meanwhile iron and polyphenol are supplemented.

The invention relates to the technical field of graphene processing, and particularly discloses a nano graphene powder preparation method which comprises the following steps: weighing a graphite raw material; opening a discharge valve of the feeding cabin, and feeding the graphite raw material into the pressure stabilizing cabin; a graphite raw material is sucked into a first-stage jet mill high-pressure cabin from a pressure stabilizing cabin, first-stage jet milling is conducted, and a first-stage abrasive material is obtained; the first-stage grinding material with the thickness not larger than 10 micrometers is conveyed to a second-stage jet mill high-pressure cabin; processing the first-stage abrasive material by a second-stage jet mill high-pressure cabin to obtain a second-stage abrasive material; the second-stage grinding material with the thickness not larger than 100 nanometers is conveyed to a flow energy depolymerization cabin; the flow energy depolymerization cabin is used for processing the secondary grinding material, and nano graphene powder is obtained through screening; the high-purity graphite raw material is processed through a three-stage gradient processing framework, a negative feedback regulation scheme is introduced in each processing link, the quality of products in different stages is controlled, a progressive processing technology is constructed, and the product rate is greatly increased.

The invention belongs to the field of gene engineering, and particularly relates to a PET hydrolase mutant with high catalytic activity and application thereof. According to the invention, amino acids at the 62nd site, the 65th site, the 66th site, the 71th site, the 154th site, the 156th site, the 177th site, the 183th site, the 184th site, the 209th site, the 213th site, the 214th site and the 215th site in the PES-H1L92F / Q94Y amino acid sequence of the PET hydrolase shown as SEQ ID NO.2 are mutated by utilizing a structural analysis and site-specific mutagenesis technology to obtain various mutants, and the mutants with improved catalytic activity are obtained. The PET hydrolase mutants promote the hydrolysis efficiency of ester bonds in PET so as to improve the degradation capacity of PET plastics, and can be applied to enzymatic depolymerization of PET plastics in life in the future.

The invention discloses a method for efficiently depolymerizing waste PET polyester at low temperature, which comprises the following steps of: dissolving a cleaned and dried PET material with a good solvent, and distilling to recover the solvent after the PET material is completely dissolved, so as to obtain a PET sample; mixing the treated PET sample with a catalyst, ethylene glycol and a cosolvent, putting the mixture into a pressure-resistant reaction tube, stirring and reacting for a certain time at a specific temperature, and then ending the reaction; carrying out reduced pressure distillation on the reaction liquid to recover the cosolvent; stirring the residual solution in hot water for a certain time, performing hot filtration, washing and drying filter residues with hot water, refrigerating filtrate in a refrigerator, filtering, collecting solids, and drying to obtain the product. The method has the advantages of simplicity in operation, low reaction temperature, high reaction rate, no metal ions and the like, and can realize green and efficient recovery of waste polyester; the method can be applied to the fields of polyester fibers, bottle flakes, films and the like, and has relatively high industrial feasibility and application prospects.

This invention belongs to the field of high-value utilization technology of biomass resources, and discloses a method for catalyzing the depolymerization of lignin into phenolic compounds using a RuNiZn / Nb2O5 catalyst. The method includes: uniformly mixing the RuNiZn / Nb2O5 catalyst, lignin-containing biomass feedstock, and water; stirring under hydrogen atmosphere to carry out the depolymerization reaction; after the reaction, cooling to room temperature and performing solid-liquid separation; evaporating the solvent to obtain the hydrogenated depolymerization product containing monophenols. In this invention, the RuNiZn / Nb2O5 catalyst employs a technique of replacing precious metals with various non-precious metals, which improves the catalyst's reactivity and reduces the amount of precious metals used. This increases the yield of lignin depolymerization products, provides milder depolymerization reaction conditions, and ultimately significantly reduces the catalyst preparation cost and the energy cost of the lignin depolymerization process.

The invention belongs to the technical field of copolymerization modification of degradable polyester, and relates to a depolymerization method and application of polybutylene terephthalate. During depolymerization, polybutylene terephthalate, dimethyl carbonate and dihydric alcohol are mixed and then subjected to a depolymerization reaction, and an intermediate ester is prepared; the dihydric alcohol is dihydric alcohol which does not form a ring with dimethyl carbonate in the depolymerization reaction process; the molar weight of the dimethyl carbonate is 10-30% of the molar weight of a repetitive unit of the polybutylene terephthalate; the sum of the molar weight of a 1, 4-butanediol unit in the polybutylene terephthalate and the molar weight of the added dihydric alcohol is a, the sum of the molar weight of a terephthalic acid unit in the polybutylene terephthalate and the molar weight of the added dimethyl carbonate is b, and the ratio of b to a is (1.2-1.5): 1; during application, the prepared intermediate ester is subjected to transesterification under the condition of negative pressure to obtain the copolyester. The depolymerization method is simple and easy to implement; the depolymerization product can be directly applied.

A polymerization raw material obtained by the depolymerization of waste polyester is disclosed. The polymerization raw material contains recycled bis(2-hydroxyethyl) terephthalate in which the contents of acetate-based ester compounds and diethylene glycol ester compounds are adjusted to specific levels. The polymerization raw material is excellent in purity and quality, and free from the problem that thermal resistance characteristics deteriorate in the polymerization of a polymer from the recycled monomer.

The invention discloses a fungal cutinase CpL-5Ct1 and an application of the fungal cutinase CpL-5Ct1 in degradation of polyurethane plastics. When the cutinase CpL-5Ct1 is used for degrading the PU foam, the shape of the PU foam can be obviously changed within 3 days at the temperature of 55 DEG C, and the PU foam is in a broken powder shape; the plastic biological enzyme method depolymerization technology is mild in condition, efficient in process, few in by-product and environmentally friendly, is an ideal means for waste plastic treatment, and has important application value in the aspects of waste PU plastic treatment and resource utilization.

The application belongs to the technical field of regenerated polyester, and particularly relates to a recycling method of waste polyester textiles, which comprises the following steps: decolorizing colored waste polyester textiles by using a decolorizing agent, wherein the decolorizing agent is one or more of dimethyl carbonate, diethyl carbonate and methyl ethyl carbonate; depolymerizing the decolorized polyester textiles by using a depolymerizing agent to obtain terephthalate, wherein the depolymerization rate of the decolorized polyester textiles is 98.0-100%; converting the terephthalate into DMT first, and then performing a re-polymerization reaction on the DMT, ethylene glycol, a catalyst and a functional additive to obtain regenerated PET. The application adopts a process of decolorizing first and then depolymerizing, and the decolorizing and depolymerizing are coordinated, so that the process is simplified, the energy consumption and pollution are reduced, and the economy and sustainability of the recycling of waste polyester textiles are improved.

The invention discloses a marine-derived carboxylesterase and an application of the marine-derived carboxylesterase in degradation of PET (Polyethylene Terephthalate) plastics. The amino acid sequence of the enzyme is as shown in SEQ ID NO.1, experiments show that Tm of RbCE1 is 79.5 DEG C, 40 mM of depolymerization monomers can be generated after the enzyme treats low-crystallinity PET powder at 60 DEG C for 4 hours, the catalytic activity is equivalent to that of LCC, and good degradation activity is shown. Through escherichia coli heterologous expression, 0.4 g / L high expression quantity can be achieved in a shake flask, and the potential of remarkably reducing the enzyme production cost is achieved. Therefore, the novel carboxylesterase RbCE1 is suitable for degrading PET plastics and composite materials thereof, and is a potential enzyme preparation for efficient biological catalysis of a waste PET plastic waste enzymatic depolymerization recovery treatment process.

The invention provides an amphiphilic nitrogen-doped coal-based carbon dot and a preparation method thereof, and belongs to the technical field of carbon nanomaterials. The method comprises the following steps: performing oxidation-depolymerization treatment on coal by using a mixed solution of formic acid and hydrogen peroxide to obtain coal-based carbon dots; uniformly dispersing the coal-based carbon dots and polyamine in a solvent 1, and then carrying out hydrothermal reaction 1 to obtain nitrogen-doped coal-based carbon dots; dissolving the nitrogen-doped coal-based carbon dots in a solvent 2, and then adding halogenated alkane for reaction 2 to obtain an intermediate product; the intermediate product is dissolved in a solvent 3, then a catalyst and a sulfonating agent are added for a reaction 3, and the amphiphilic nitrogen-doped coal-based carbon dots are obtained. The coal-based carbon dots have controllable hydrophilic and hydrophobic structures, excellent surface activity and interfacial activity, excellent dispersion stability and ultralow interfacial tension in a high-salinity oil-water system, and can meet the actual application requirements in the fields of oil-water interface regulation and control, solid-liquid interface wetting regulation and control and the like.

The invention discloses a method for recycling rare metals through Joule thermal coupling alkali depolymerization, and belongs to the technical field of solid waste treatment. The Joule heat technology and alkali depolymerization are combined, an alkali agent is introduced according to the characteristic that inorganic solid waste is rich in silicate phases, complex mineral structures such as silicate in the inorganic solid waste are destroyed through the alkali depolymerization effect, meanwhile, decomposition of the mineral structures is further accelerated by means of rapid phase change triggered by Joule heat, and therefore the inorganic solid waste can be recycled. Therefore, favorable conditions are created for release of rare metals. Through the cooperation mechanism of Joule heat induced rapid phase change and alkali depolymerization, extraction of rare metals in the solid waste is enhanced, meanwhile, the potential environmental risk of heavy metals is reduced, efficient and low-carbon resource utilization of inorganic solid waste is achieved, and the method has important practical guiding significance for construction of a sustainable development waste-resource circulation system in the metallurgical industry.

Disclosed is a process for hydrolytic depolymerization of a polyamide contained in a chemical feedstock F, wherein the process comprises: providing the chemical feedstock F; providing a liquid aqueous stream SW; preparing a mixture comprising the raw material F and the liquid aqueous stream SW and subjecting said mixture to polyamide 6 depolymerization conditions in a chemical reaction unit UR, thereby obtaining an aqueous stream SE exiting the UR, the stream SE comprising epsilon-caprolactam, wherein the mixture to be subjected to polyamide 6 depolymerization conditions comprises polyamide 6 and further comprises polyethylene terephthalate and polyamide 6.6 in a mass ratio rS = (mPA6.6 + mPET) / mPA6, wherein 0.01 < = rS < = 2.5.

Disclosed herein are a catalyst for polyester depolymerization or cyclic ester synthesis, a preparation method therefor and a use thereof. The catalyst is a long-chain catalyst having a main chain carbon atom number greater than or equal to 8, and containing a terminal ion group and a terminal hydroxyl structure; the catalyst may be used to catalyze polyester hydrolysis, alcoholysis or cyclic depolymerization, so as to recover corresponding monomers or monomers and oligomers, or used to catalyze hydroxy acid or hydroxy acid esters to synthesize cyclic ester monomers or cyclic ester monomers and cyclic oligomers by means of polycondensation and cyclization reactions. The catalyst may reduce the viscosity of a reaction system, and may greatly improve the utilization rate of a catalytic active center, reduce the consumption of the catalyst and improve overall catalytic efficiency, achieving high-efficiency, high-yield and selective depolymerization of polyester homopolymers, copolymers, blends or compounds.

The invention discloses a method for preparing high-value chemicals through photocatalytic driving of beta-O-4 lignin depolymerization and coupling cascade reaction, and belongs to the technical field of photocatalytic biomass resource conversion. The method comprises the following steps: (1) dispersing a beta-O-4 lignin raw material into a solvent containing a photocatalyst; (2) introducing a normal-temperature chemically stable gas to replace air in a reaction system; and (3) carrying out a depolymerization reaction of beta-O-4 bonds and an in-situ C-C bond coupling reaction under an illumination condition to generate a target product. And (4) separating and purifying the product and recovering the catalyst. Through photocatalytic cascade reaction design, the defects of harsh reaction conditions and multi-step separation in a traditional method are avoided, the method has the advantages of mild reaction conditions, high atom utilization rate, high product selectivity and environmental friendliness, and a new way is provided for high-value utilization of lignin.

The invention provides a waste PET lining cloth grading alcoholysis and in-situ polymerization regeneration method, and relates to the technical field of waste textile recycling, and the method comprises the following steps: adopting a near infrared spectrum combined AI image identification technology to realize waste PET lining cloth material classification, and removing pollutants through low temperature plasma-biological enzyme synergistic cleaning; putting the pretreated PET fragments into three-stage series reaction kettles, and dynamically adjusting the temperature and the catalyst concentration of each stage of reaction kettle through a control algorithm to realize PET depolymerization degree gradient control; according to the method, the graded alcoholysis and in-situ polymerization synergistic technology is adopted, so that the performance of the waste PET lining cloth regenerated fiber is improved in a leap-over manner, the molecular weight and the fiber strength of the regenerated PET are improved through the three-stage tandem reaction kettle and the control algorithm, and the technical bottlenecks that the strength of a physical method is low and the molecular weight loss of a chemical method is large are broken through; the mechanical property of the regenerated material is obviously improved.

The invention discloses a fatigue-resistant degradable epoxy resin composite material and a preparation and degradation method thereof, and belongs to the technical field of fatigue-resistant recyclable epoxy resin. The composite material comprises a component A and a component B, the mass ratio of the component A to the component B is 100: (30-65), and every 100 parts of the component A comprises 0-94% of epoxy resin, 0-50% of an epoxy resin diluent, 1-30% of an epoxy resin anti-fatigue catalyst and 5-60% of an epoxy resin modifier; every 100 parts of the component B comprises 10%-90% of an amine curing agent, 5%-85% of an anhydride curing agent and 0%-5% of an accelerant. The epoxy resin modifier is added, dynamic covalent bonds are introduced into an epoxy resin cross-linked network, when the dynamic covalent bonds are subjected to external stimulation, the dynamic covalent bonds in the cross-linked network are broken, a three-dimensional network is temporarily or permanently depolymerized, waste epoxy resin can be degraded under a certain condition, and the environmental pollution pressure is relieved.

The present invention provides a method for purifying a polyester depolymerization product in which impurities and poorly soluble dyes and pigments are removed from a material produced by polyester depolymerization so as to minimize impurity content and perform decolorization.

A recycling system comprises a partial depolymerization unit 730, which partially decomposes a solid material, such as PET flakes containing a polymer to be recycled, into a depolymerized product through a depolymerization reaction; a solid-liquid separation unit 740, which separates a solid component and a liquid component obtained in the partial depolymerization unit 730; and a recycling device that performs a recycling process on the solid component. The recycling device is a mechanical recycling device 900, which performs a mechanical recycling process on the solid component. The recycling system also includes a chemical recycling device 100, which performs a chemical recycling process on the liquid component.

The invention discloses a method for recovering monohydroxyethyl terephthalate from a polyester textile, which comprises the following steps: carrying out multi-stage decolorizing treatment on the polyester textile to be recovered by using ethylene glycol as a decolorizing agent to obtain the decolorized polyester textile; mixing a depolymerization catalyst, a sodium phosphate buffer solution and the decolored polyester textile, and carrying out a depolymerization reaction to obtain a depolymerization solution; adding ethyl acetate into the depolymerization liquid for extraction, rotary evaporation concentration and sublimation treatment to obtain monohydroxyethyl terephthalate. According to the method for recycling the monohydroxyethyl terephthalate from the polyester textile, the decolorization rate of the polyester textile can reach 90% or above, the purity of the recycled monohydroxyethyl terephthalate is larger than 98%, and the whiteness of the recycled monohydroxyethyl terephthalate is larger than 97%. The method for recycling the monohydroxyethyl terephthalate from the polyester textile, provided by the invention, is an efficient, economical and green new method for recycling the polyester, and the recycling of the polyester textile is realized.

The invention belongs to the technical field of bioengineering, and particularly relates to collagen tripeptide as well as a preparation method and application thereof. The method comprises the following steps: carrying out depolymerization treatment on a raw material containing collagen to construct a magnetic immobilized enzyme; by utilizing the magnetic immobilized enzyme, raw materials subjected to depolymerization treatment are subjected to enzymolysis at a certain temperature, pH and reaction time, and with the assistance of a magnetic field, rapid separation and cyclic utilization of the immobilized enzyme can be realized. And finally, carrying out enzyme deactivation, solid-liquid separation and ultrafiltration to obtain the collagen tripeptide with GPH content of more than or equal to 59wt.%, and compared with the existing collagen tripeptide, the collagen tripeptide has higher GPH content. The preparation method is simple in process, easy and convenient to operate, low in cost, capable of achieving mass production and suitable for industrialization, and has remarkable practicability and economic benefits.

The invention relates to the field of preparation of negative electrode materials, in particular to a depolymerization method of a carbon-coated negative electrode material, which comprises the following steps: (1) carrying out surface activation treatment on an agglomerated carbon-coated negative electrode material to reduce Van der Waals' force among particles; (2) depolymerizing the activated particles through a spinning roller mill, injecting a carbon precursor into the spinning roller mill, and primarily carbonizing the carbon precursor by using friction heat of the spinning roller mill to form a surface repairing layer; and (3) carrying out graded screening on the depolymerized particles, screening out particles with target particle sizes, and carrying out secondary high-temperature carbonization to form a complete carbon coating layer. According to the method, through three-stage process cooperation of surface activation, dynamic carbon repair and closed-loop grading, the bottlenecks of low efficiency, large damage and high cost in the traditional depolymerization technology are broken through, and the economical efficiency of large-scale production is realized while the electrochemical performance of the material is improved.