35 results about "Organic phosphates" patented technology

The invention discloses a polypropylene composition as well as a preparation method and application thereof, and belongs to the technical field of materials. The polypropylene composition comprises 100 parts by weight of polypropylene; 0.1 to 0.8 part by weight of an antioxidant; 0.01 to 0.3 part by weight of a nucleating agent; 0.01 to 0.1 part by weight of an acid acceptor; 0.01 to 0.1 part by weight of an antistatic agent; the polypropylene is selected from homo-polypropylene, an ethylene-propylene random copolymer or a propylene-butylene random copolymer; the nucleating agent is selected from an organic phosphate nucleating agent or a beta-type nucleating agent; the antistatic agent is selected from fatty acid alkanolamide and / or fatty acid monoglyceride. Through the combined action of the nucleating agent, the antistatic agent and other components (polypropylene, the antioxidant and the acid acceptor), the polypropylene composition has good high temperature resistance, impact resistance and stiffness, and is suitable for preparing a thermoforming packaging material, especially a hot filling bottle under the ultrahigh temperature (121 DEG C) sterilization condition.

The invention provides an anti-interference material and a preparation method thereof, an anti-interference film and a biosensor, the anti-interference material comprises an anionic polymer formed by polymerizing a monomer I and a monomer II, the monomer I is a monomer with a carbon-carbon double bond and a nitrogen heterocyclic ring, and the monomer II is a monomer with a carbon-carbon double bond and a nitrogen heterocyclic ring. The monomer II is organic sulfonate, organic carboxylate or organic phosphate with carbon-carbon double bonds, and the molar ratio of the monomer I to the monomer II is 1: 1 to 15: 1. Therefore, the anti-interference material can achieve an anti-interference effect on the anionic electrochemical active interferent.

The application discloses a limiting distribution model for predicting accumulation of organic phosphates (OPEs) in rice grains and a construction method thereof, and belongs to the technical field of environmental pollutant migration prediction and agricultural safety. The model is based on the limiting distribution theory, systematically identifies four key links (soil-root absorption, root-stalk transportation, stalk-leaf distribution and leaf-grain migration) of OPEs migration from soil to rice grains and limiting factors of each link, realizes accurate prediction of grain accumulation under different OPEs, different environmental conditions and different rice varieties by quantifying and integrating distribution coefficients of each link. The application calibrates distribution coefficient equations of each link by measuring physical and chemical parameters of OPEs, soil environmental parameters, rice physiological parameters and in-vivo distribution data, the relative error of model prediction is less than or equal to 15%, the model can be applied to farmland OPEs pollution risk assessment, optimization of prevention and control measures and food safety early warning, and has the advantages of strong universality, simple operation and accurate prediction.

The invention discloses a graphene oxide corrosion inhibitor and a preparation method thereof. The corrosion inhibitor is prepared by reacting graphene oxide with an organophosphorus corrosion inhibitor. The preparation method comprises the following steps: dispersing graphene oxide in a solvent; adding an organophosphorus corrosion inhibitor to carry out amination reaction; and filtering, washing, drying and grinding. According to the graphite oxide corrosion inhibitor, organic phosphate is introduced to a base plane, on one hand, the interlayer distance can be increased, the maze effect of graphene oxide is enhanced, on the other hand, the water solubility is improved through phosphate anions, meanwhile, agglomeration of graphene oxide is prevented through the electrostatic repulsion effect between the phosphate anions, and when the corrosion inhibitor is deposited on the surface of metal, the corrosion inhibitor has the good corrosion resistance. And an excellent slow-release effect can be obtained.

The invention discloses a polyphenylene sulfide composite material as well as a preparation method and application thereof, and relates to the technical field of high polymer materials. The invention provides a polyphenylene sulfide composite material. The polyphenylene sulfide composite material comprises the following components in parts by weight: 50-90 parts of PPS resin, 0.3-1.5 parts of a nucleating agent, 0.3-1.5 parts of a silane coupling agent and 10-45 parts of glass fibers, the nucleating agent is a mixture of an organic phosphate nucleating agent and a sorbitol nucleating agent; the melt mass flow rate of the PPS resin is greater than or equal to 200g / 10min under the conditions that the test temperature is 316 DEG C and the load is 5kg according to ISO 1133-2022. According to the invention, through selection of components such as the specific nucleating agent, the PPS composite material with high laser transmittance and high welding strength under high crystallinity is prepared.

This invention discloses a compound modified masterbatch for improving the heat-sealing strength of PLA tea bags and its preparation method, belonging to the field of polymer materials technology. By weight, it comprises the following components: 35-50 parts polylactic acid carrier; 18-28 parts toughening agent; 3-8 parts composite nucleating agent; 1-4 parts crystallization promoter; 2-5 parts interface compatibilizer; and 0.5-2 parts antioxidant. The toughening agent is a blend of polybutylene adipate-terephthalate and polybutylene succinate in a mass ratio of (1.5-2.5):1. The composite nucleating agent is composed of an organophosphate nucleating agent and an acylhydrazine compound in a mass ratio of 1:(0.8-1.5). This invention systematically improves the heat-sealing strength of PLA tea bags from three dimensions—toughening, nucleation, and promotion—from the perspectives of interfacial adhesion, crystal structure, and molecular motion, overcoming the limitations of single modification methods.

The present invention provides a diluent for synthetic fiber treatment agent capable of reducing fluff. The diluent must contain a smoothing agent (L), a nonionic surfactant (N), and a straight-chain hydrocarbon (P) having 11 to 14 carbon atoms, and at least one selected from an oil film enhancer (H), an organic sulfonate (AS), an organic phosphate (AP), an oxirane adduct of an organic amine (RA), a low viscosity diluent (D), and an antioxidant (E), the straight-chain hydrocarbon (P) must contain a straight-chain hydrocarbon having 13 carbon atoms and a straight-chain hydrocarbon having 14 carbon atoms, the straight-chain hydrocarbon (P) optionally contains a straight-chain hydrocarbon having 11 carbon atoms and / or a straight-chain hydrocarbon having 12 carbon atoms, the straight-chain hydrocarbon (P) satisfies the following formula (1), and the straight-chain hydrocarbon (P) has a weight ratio of 8 to 50% in the diluent for synthetic fiber treatment agent. 1 < weight % of straight-chain hydrocarbon having 13 carbon atoms / weight % of straight-chain hydrocarbon having 14 carbon atoms < 10 (1).

A hydroformylation process for preparing 3,5,5-trimethylhexanal comprising reacting 2,4,4-trimethylpent-2-ene with H2 and CO in a reaction zone in the presence of one or more free organophosphite ligands of the general formula (I)wherein R1, R2, R3, R4 and R5 are each independently H, C1- to C9-alkyl or C1- to C9-alkoxy and R1, R2,R3, R4 and R5 are not H at the same time, andR6, R7, R8, R° and R1° are each independently H, C1- to C9-alkyl or C1- to C9-alkoxy and Re, R7,R8, R° and R1° are not H at the same time, andR11, R12, R13, R14 and R15 are each independently H, C1- to C9-alkyl or C1- to C9-alkoxy and R11,R12, R13, R14 and R15 are not H at the same time,and a homogeneous rhodium catalyst complexed with one or more organophosphite ligands of the general formula (I) at a pressure of 1 to 100 bar abs and a temperature of from 50 to 200° C.

The invention belongs to the technical field of pollutant detection and environmental protection, and discloses a drainage basin water environment organophosphate pollution health risk assessment management and control method and system, and the method comprises the steps: S1, biomarker screening; s2, constructing a dynamically associated drainage basin water environment health risk management and control evaluation model; s3, collecting multi-medium samples at multiple points; s4, detecting the sample and acquiring concentration data; and S5, performing drainage basin water environment health risk management and control assessment. According to the embodiments of the invention, through software and hardware combination, multi-medium and multi-model combination, on the basis of screened biomarkers, simplified characteristic parameters and concentration detection data, dynamically associated drainage basin water environment health risk management and control evaluation analysis is supported, a result with high credibility can be obtained, four links of sampling, detection, analysis and early warning are greatly simplified, and the reliability of the system is improved. Fund, labor, instruments, consumables and time required by administrative supervision are greatly reduced, and large-scale, large-range and low-cost popularization and application are facilitated.

The present invention discloses a water-based protective agent for nickel-phosphorus alloy coatings, a preparation method, and applications. The water-based protective agent comprises the following components by weight: 50 to 150 parts of amide, 30 to 100 parts of liquid rosin derivatives, 10 to 100 parts of sebacic acid ester, 5 to 50 parts of organic phosphates, 5 to 50 parts of organic borates, 1 to 20 parts of nonionic surfactants, 0.1 to 10 parts of passivators, and 500 to 900 parts of water. The water-based protective agent can passivate the coating and form a colorless, continuous, dense, hydrophobic, and corrosion-inhibiting thin film on the surface of the coating, sealing the coating pores and significantly improving the salt spray corrosion resistance of the coating without affecting the surface energy and welding performance of the coating. As a water-based system, the overall system is more environmentally friendly.

Disclosed herein are compositions, methods, and articles of personal protective equipment for use in detoxifying an organophosphate-based agent, wherein the compositions, methods, and articles comprise contacting the organophosphate-based agent with a cocaine esterase, wherein the contacting detoxifies the organophosphate-based agent.

The invention relates to the field of material science, and discloses a flame-resistant and flame-retardant material prepared from recycled ABS, and the flame-resistant and flame-retardant material is prepared from the following components in parts by mass: 50-70 parts of recycled ABS matrix; 10 to 20 parts of natural plant fiber; 5 to 15 parts of an organic phosphate flame retardant; and 5-10 parts of aluminum hydroxide. The particle size of the recycled ABS matrix is 1-5 mm, and the recycled ABS matrix is ABS particles which are recycled from a waste ABS material and are subjected to pretreatment cleaning, drying and crushing; the natural plant fibers are bamboo fibers, the fiber length of the bamboo fibers is 50-200 mm, the fiber diameter of the bamboo fibers is 100-500 microns, and the plant fibers are subjected to chemical pretreatment to remove impurities. By introducing the organic phosphate flame retardant and the bamboo fibers, the flame retardant property and the mechanical property of the composite material are improved, and the tensile strength and the ductility of the material are enhanced.

The invention relates to a V-W type active liquid auxiliary agent with high stability and a preparation method thereof, and the V-W type active liquid auxiliary agent comprises the following components by mass: 1-10% of ammonium metavanadate; 1 to 10% of ammonium metatungstate; 1-15% of oxalic acid; 0.4-1% of an organic chelating agent, and the balance being deionized water. The organic chelating agent is one or a mixture of organic phosphate or organic carboxylate; the ratio of the organic phosphate to the organic carboxylate ranges from 1: 8 to 5: 1; according to the method, the material cost is low, and under the same active liquid concentration, if the hydrolysis rate of the active liquid is about equal to 0, only the proportion of the organic chelating agent in the method needs to be increased to 0.4% or above; in addition, the active liquid has high stability, after the organic chelating agent is added, the stable period of the active liquid can be maintained for a long time, and no hydrolysate is generated even if the active liquid is stored for a long time.

The invention relates to the technical field of luminescent materials, in particular to an organic-phosphate hybrid afterglow luminescent material with visible light excitation performance as well as a preparation method and application of the organic-phosphate hybrid afterglow luminescent material. The organic-phosphate hybrid afterglow luminescent material is prepared by mixing phosphate and fluorescein or a derivative thereof, heating, and cooling to room temperature. The preparation method is simple to operate, and the obtained afterglow composite material is excellent in luminescence property. The luminescent material can be used as a temperature sensing label, a characteristic luminescent material in latent fingerprint imaging identification or biological tissue (such as muscular tissue or gastric mucosa) imaging identification process.

The invention belongs to the technical field of electrochemical energy storage materials, and discloses a preparation method of a high-dissociation flame-retardant electrolyte. The preparation method comprises the following steps: adding a lithium salt and a nitrogen-containing compound into organic phosphate, stirring, then adding an inorganic nano-material with high dielectric property, and then carrying out ultrasonic dispersion on the mixed system to obtain the high-dissociation flame-retardant electrolyte. According to the preparation method disclosed by the invention, a nitrogen-containing compound is added to construct a nitriding interface, so that the cycling stability and compact and smooth dendritic-crystal-free morphology of lithium are improved, voltage polarization is favorably reduced, the cycle life is prolonged, and a high-energy-density battery with excellent safety is obtained; the lithium ion migration power of an electrolyte system is improved, the concentration polarization is effectively reduced, the growth of lithium dendrites is inhibited, and the ultra-stable cycle performance of the whole battery is realized. In addition, the preparation method is easy to operate, low in cost and suitable for industrial mass production, and has good application prospects.

The present invention relates to the technical field of preparation of polyethylene modified materials. Disclosed are a modifying additive and a polyethylene modified material composition, a polyethylene modified material, and a preparation method therefor and a use thereof. The modifying additive is an organic compound and / or an inorganic substance. The lengths of the modifying additive in the x, y, and z directions in three‑dimensional space do not exceed 200 μm, and the melting point of the modifying additive is greater than or equal to 139.0°C. The organic compound is selected from one or more of sorbitol benzylidene derivatives, aliphatic carboxylic acid metal compounds, aromatic carboxylic acid metal compounds, organic phosphates, lignic acids and derivatives thereof. The inorganic substance is selected from one or more of metals, non-metal solid oxides, and non-metal elemental substances. By using the modifying additive, the viscosity of the polyethylene modified material during flow-field processing can be reduced, and the molecular weight distribution thereof can be utilized to improve the degree of orientation, thereby enhancing the lateral impact resistance of a final product.

The invention relates to the technical field of foaming agents, and provides a high-foaming-ratio foaming agent and a preparation process thereof. The foaming agent with the high foaming ratio comprises the following components in parts by mass: 10-20 parts of a nonionic surfactant, 0.5-1.5 parts of phosphate, 4.2-12 parts of an auxiliary agent and 68-85.8 parts of a solvent, and the phosphate comprises organic phosphate and inorganic phosphate. According to the technical scheme, the problem that a nonionic foaming agent in the prior art is poor in foaming capacity is solved.

The invention discloses an electrified fire extinguishing agent capable of blocking and extinguishing open fire and cooling and a preparation method, and the electrified fire extinguishing agent comprises the following components in parts by weight: 50-70 parts of a fire extinguishing agent, 20-40 parts of a flame retardant, 5-10 parts of a cooling agent, 5-10 parts of an adsorbent and 5-10 parts of a neutralizer. The flame retardant is prepared from the following components in parts by weight: 20 to 40 parts of organic phosphate, 20 to 40 parts of flame-retardant polymer, 20 to 40 parts of nitrogen and 20 to 40 parts of silicon powder, and the cooling agent is prepared from the following components in parts by weight: 30 to 50 parts of cooling master batch, 10 to 30 parts of inorganic salt, 10 to 30 parts of high-molecular polymer and 10 to 30 parts of nano material. And alkaline substances such as sodium hydroxide or calcium hydroxide are used for neutralizing hydrogen fluoride and converting the hydrogen fluoride into harmless fluoride, so that byproducts generated after fire extinguishing by the fire extinguishing agent are decomposed, and the situation that the byproducts pollute the environment around fire extinguishing is avoided.

The present application provides a lithium-replenishing additive, a preparation method thereof, and a secondary battery. The lithium-replenishing additive comprises a lithium-rich material core and a coating disposed on the lithium-rich material core. The coating comprises an organophosphorus compound, the organophosphorus compound comprising an organophosphate or an organophosphate salt, and / or the organophosphorus compound comprising an organophosphorus acid or an organophosphorus acid salt. The substituents in the organophosphate or the organophosphate salt, the organophosphorus acid or the organophosphorus acid salt are independently selected from substituted or unsubstituted alkyl groups or silicon-containing groups, and the substituents of the alkyl groups comprise fluorine atoms, hydroxyl groups, carboxyl groups, amino groups, and amide groups. The lithium-replenishing additive not only effectively replenishes lithium in lithium secondary batteries and improves the initial efficiency of the battery, but also has good stability and is not easily reacted in air, which facilitates the production, storage, and transportation of the lithium-replenishing additive.

The invention belongs to the technical field of pollutant detection and environmental protection, and discloses a drainage basin water environment organophosphate pollution ecological risk assessment monitoring method and system, and the method comprises the steps: S1, biomarker screening; s2, constructing a dynamically associated watershed water environment ecological risk assessment model; s3, collecting multi-medium samples at multiple points; s4, detecting the sample and acquiring concentration data; and S5, evaluating and monitoring the ecological risk of the water environment in the drainage basin. Through software and hardware combination, multi-medium and multi-model combination, based on screened biomarkers, simplified characteristic parameters and concentration detection data, dynamically associated drainage basin water environment ecological risk assessment analysis is supported, a result with high credibility can be obtained, four links of sampling, detection, analysis and early warning are greatly simplified, and the reliability of the system is improved. The expenditure, labor, instruments, consumables and time required by administrative supervision are greatly reduced, and large-scale, large-range and low-cost popularization and application are facilitated.

The invention discloses an extracting agent for purifying raffinate acid as well as a preparation method and application of the extracting agent, and relates to the technical field of raffinate acid purification. The extraction agent for purifying the raffinate acid consists of 15-40 parts of water-insoluble organic sulfonic acid, 10-35 parts of water-insoluble organic phosphate compound and 30-75 parts of water-insoluble organic solvent. The preparation method of the extraction agent comprises the following steps: adding the organic sulfonic acid and the organic phosphate compound into the organic solvent, and fully stirring for 10-30 minutes. The extraction agent and the raffinate acid are mixed according to the proportion, so that the concentration of impurity ions (metal ions such as iron, aluminum and magnesium) in the raw material acid is effectively reduced, and the MER value in the raffinate acid can be effectively reduced. When the extraction agent is used for a cyclic extraction and purification experiment on pilot plant test equipment, the MER value can be effectively reduced during continuous circulation, and the extraction agent can still be recycled, which fully shows that the recycling period of the extraction agent is long.

This disclosure relates to an inorganic-organic metal phosphate ceramic coating from the reaction of an inorganic phosphate of the formulas (i) Am(H2PO4)m·nH2O or (ii) AH3(PO4)2·nH2O; where A is ammonium or an m-valent metal element; m=1, 2, or 3; and n is 0 to 25; and at least one metal oxide or hydroxide represented by the formula B2mOm or B(OH)2m, where B is a 2m-valent metal; and m=1 or 1.5; thereof; and at least one polymer capable of reacting with at least the one metal oxide or hydroxide; or a first organic precursor combined with the inorganic phosphate and a second organic precursor combined with the at least one metal oxide or hydroxide, the second organic precursor configured to chemically react with the one or more first organic precursor.

The present invention relates to a non-aromatic asymmetric mono(2-cyanoethyl)triorganophosphonium salt, its synthesis process and its use as an electrolyte compound, as a lubricant and lubricant additive, as a gas capture agent, as a solvent for catalysis and as a surface modification agent by Chemie Click.

The application relates to the technical field of medical packaging materials, and particularly discloses a high-temperature and high-pressure resistant modified polypropylene resin, a preparation method thereof and a vaccine bottle processed by using the same. The high-temperature and high-pressure resistant modified polypropylene resin is mainly made of the following raw materials: polypropylene resin, hydrogenated styrene-butadiene-styrene block copolymer, modified nano montmorillonite, organic phosphate nucleating agent, calcium stearate, hindered phenolic antioxidant and phosphite antioxidant. The modified nano montmorillonite is obtained by treating nano montmorillonite with 3-(methacryloyloxy)propyl trimethoxysilane, maleic anhydride, glycidyl methacrylate and dodecafluoroheptyl methacrylate. The modified polypropylene resin has the characteristics of high tensile strength, high impact strength, high heat resistance and high barrier property, can meet the high-temperature sterilization requirement of 121 DEG C for 30 min, and the vaccine bottle does not soften, deform or collapse during high-temperature sterilization, and the sealing integrity is maintained.

The invention relates to the field of road engineering, in particular to a direct-vat warm-mixing flame-retardant SBS asphalt modifier as well as a preparation method and application thereof. The modifier comprises 40-60 parts of a polystyrene branched polymer, a cross-linking agent accounting for 0.2-0.4% of the weight of the polymer, 10-20 parts of biodiesel and 10-20 parts of a composite flame retardant. Wherein the molecular weight of the polystyrene branched polymer is preferably 100,000-150,000, and the polystyrene branched polymer is prepared by introducing a branched structure into a linear styrene-butadiene-styrene block copolymer; the biodiesel takes waste animal or vegetable fat as a raw material; the composite flame retardant contains 30%-50% of an organic phosphate flame retardant and 50%-70% of an inorganic flame retardant. The modifier can be directly added into an asphalt mixture mixing pot, can reduce the production and construction temperature by 20-30 DEG C, improves the high-temperature rut resistance and low-temperature crack resistance of asphalt, is flame-retardant, free of toxic and corrosive gases, low in cost and simple in process, and is suitable for pavement of asphalt pavements of highway tunnels.

The present invention discloses a method for preparing a morphology-controllable polypropylene nucleating agent. The method comprises dissolving an organic phosphate in an organic solvent, adding a surfactant, and mixing the solution with water in a planar oscillating reactor placed under ultrasound to precipitate the organic phosphate. The organic phosphate is then separated and dried to obtain organic phosphate crystals of various shapes and sizes. This method can precisely control the shape and size of the organic phosphate crystals to obtain monodisperse organic phosphate crystals. The organic phosphate crystals also have a narrow particle size distribution, stable quality, high yield, and high nucleation efficiency. The resulting crystals are micron-sized powder particles with uniform particle size. When used as a polypropylene nucleating agent, the crystals can be easily and evenly dispersed in a polypropylene resin material, thereby improving their nucleation efficiency. The method is simple to operate, has a short processing time, low energy consumption, mild conditions, and low cost, and can be used for industrial large-scale continuous production.

A composition for extracting a metal, the composition comprising an organic phase comprising an organic solvent and an organic phosphate. The composition may comprise a crown ether. The crown ether may comprise B15C5 crown and the organic solvent may comprise chloroform, toluene, xylene, dichloroethane, trichloroethane, heptane, 1,2-dichlorobenzene, or a combination thereof. The organic phase may further comprise an alcohol. A method for extracting a metal, the method comprising disposing an organic phase comprising an organic solvent and an organic phosphate; and an aqueous phase comprising a metal salt and a base into a high-speed countercurrent chromatograph.

The application relates to the technical field of building materials, and particularly discloses a steel slag asphalt concrete anti-stripping agent and a preparation method thereof. The steel slag asphalt concrete anti-stripping agent comprises the following raw materials: an organic amine modifier, an organic phosphate, a silane coupling agent, nano silicon dioxide, a complexing agent, a polyhydric alcohol ester and inorganic mineral micro powder. The preparation method of the anti-stripping agent is as follows: deionized water is added into a reaction kettle, the organic phosphate, the complexing agent and the polyhydric alcohol ester are sequentially added, and stirring is uniformly carried out to obtain a mixed solution; the silane coupling agent is added into the mixed solution and uniformly stirred, then the nano silicon dioxide and the inorganic mineral micro powder are added, and stirring is continuously carried out; the organic amine modifier is added, constant-temperature reaction is carried out, after the reaction is completed, cooling is carried out to room temperature, filtration is carried out, drying is carried out, and the steel slag asphalt concrete anti-stripping agent is obtained. The anti-stripping agent has good bonding performance, good water immersion Marshall residual stability, a large freeze-thaw splitting tensile strength ratio, and excellent high-temperature stability and low-temperature anti-cracking performance.

Corrosion inhibitor compositions are provided that can include a mixture of one or more alkaline earth metals, one or more organic phosphates, one or more inorganic phosphates, optionally a dispersant, and hydroxyphosphono acetic acid and / or salts thereof and / or derivatives of hydroxyphosphono acetic acid and / or salts thereof. Methods of mitigating or inhibiting corrosion of metal surfaces are also disclosed. The methods can include the steps of adding a corrosion inhibitor composition as described in the present disclosure to a medium in contact with the metal surface and optionally to the metal surface before it is contacted by the medium.

The invention discloses a chelating agent for waste incineration treatment. The chelating agent comprises the following components in percentage by mass: 35-65% of a chitosan derivative, 20-40% of organic phosphate and 10-25% of metal chloride. The invention also discloses a preparation method of the chelating agent. The preparation method comprises the following steps: (1) a pretreatment stage: carrying out vacuum drying on the chitosan derivative at 40-60 DEG C for 2-4 hours; (2) mixing reaction stage: carrying out first stirring reaction on the pretreated chitosan derivative and organic phosphate under the condition that the pH is 5.8-6.5, controlling the reaction temperature to be 55-65 DEG C, and controlling the reaction time to be 1-2 hours; and (3) a post-treatment stage: adding a metal chloride solution at intervals for three times at an interval of 15-25 minutes, and finally carrying out ultrasonic treatment for 20-40 minutes at an ultrasonic frequency of 28-40 kHz. According to the chelating agent provided by the invention, chitosan-metal-phosphate-heavy metal three-dimensional mesh gel is formed through reaction of three components, namely the chitosan derivative, the organic phosphate and the metal chloride, and the obtained chelating agent has an extremely high metal leaching rate when being used for fly ash treatment.