2092 results about "Dicarboxylic acid" patented technology

This invention discloses a fluorene-based organic small molecule hole transport material and its applications. The general structural formula of the fluorene-based organic small molecule hole transport material is as follows: where n = 1-4, and R represents the hole transport capacity. This fluorene-based organic small molecule hole transport material is used as an undoped hole transport material in perovskite solar cell devices. By introducing dicarboxylic acid groups onto the fluorene-based organic small molecule hole transport material, when used in an inverted perovskite solar cell device, it can form chemical bonds with the hydroxyl groups of the glass conductive substrate, forming a directionally aligned self-assembled layer on the surface of the glass conductive substrate. This effectively improves the charge transport capability at the interface and increases the photoelectric conversion efficiency of the perovskite solar cell device. Furthermore, since this perovskite solar cell device does not contain lithium salts, it exhibits high water and oxygen stability. In addition, the synthesis process of this fluorene-based organic small molecule hole transport material is simple, and the raw materials are inexpensive and readily available, making it highly valuable for practical applications.

The invention discloses a colorimetric and fluorescent dual-mode nano-enzyme sensor. The colorimetric and fluorescent dual-mode nano-enzyme sensor comprises nano-enzyme, hydrogen peroxide and a colorimetric probe, wherein the nano-enzyme is prepared from ZrCl4, 2-aminobiphenyl dicarboxylic acid and Cu (NO3) 2 by a one-pot method; the colorimetric probe is TMB, can oxidize colorless TMB into blue oxTMB, generates an ultraviolet absorption peak at 652 nm, and has a strong fluorescence emission peak at 405 + / -5 nm. The zirconium-based metal organic framework UiO-67-NH2 with high stability is used as a carrier, Zr < 4 + > sites are replaced by part of Cu < 2 + >, the fluorescent nano-enzyme with peroxidase activity is formed, and the problems that free enzyme is difficult to recover, the stability is low and the like are solved.

The invention discloses construction and application of an L-malic acid producing issatchenkia orientalis strain, and belongs to the technical field of microorganisms and the technical field of microbial fermentation and metabolic engineering. Through a metabolic engineering means, a cytoplasm metabolic pathway of an issatchenkia orientalis strain is transformed, and a pyruvate decarboxylase coding gene, glycerol dehydrogenase and lactic dehydrogenase are knocked out; a pyruvate carboxylase gene derived from aspergillus flavus, a malate dehydrogenase gene derived from corynebacterium glutamicum and phosphoenolpyruvate carboxylase derived from escherichia coli are screened and integrated, so that a cytoplasm rTCA cycle synthesis pathway is enhanced; inserting a dicarboxylic acid external transporter gene from schizosaccharomyces cerevisiae at a neutral site GD21, and knocking out endogenous dicarboxylic acid internal transporter; the L-malic acid yield of the modified yeast strain in the fermentation process is remarkably increased and reaches 140.16 g / L. The engineering strain provided by the invention has good industrial application potential in efficient L-malic acid production.

The invention discloses a preparation method of antistatic modified chinlon filaments, and relates to the field of chinlon filaments. When the antistatic modified chinlon filament is prepared, (formylmethyl) diethyl phosphate and 1-aminopyrrole react to prepare pyrrole diethyl phosphate; reacting the hydroxylated multi-walled carbon nanotube with pyrrole diethyl phosphate to obtain a modified multi-walled carbon nanotube; the preparation method comprises the following steps: reacting 2, 2 '-bipyridine-5, 5'-dicarboxylic acid with 2-amino-5-nitrophenol, and then reducing to obtain a benzoxazole diamine monomer; then, adipic acid, 1, 5-diaminopentane and a benzoxazole diamine monomer are subjected to a reaction, and modified polyamide is prepared; uniformly mixing the modified polyamide, the modified multi-walled carbon nanotubes, pyrrole, ferric trichloride and copper chloride, and performing melt spinning to obtain the antistatic modified polyamide filament. The antistatic modified chinlon filament prepared by the invention has excellent antistatic, flame-retardant, anti-aging and mechanical properties.

To provide a perfluoropolyether compound expressing excellent surface tension reduction performance, and expressing excellent foamability and foam stability not only during diluting fresh water but also during diluting sea water, and a fluorine-based surface active agent including the compound.SOLUTION: A perfluoropolyether dicarboxylic acid compound or a salt thereof is expressed by the following formula (1). In the formula, Rf1 represents a 1-4C perfluoroalkyl group. R1 represents a substituted or unsubstituted 1-10C hydrocarbon group. R2 represents a substituted or unsubstituted 1-6C hydrocarbon group. R3 and R4 are same or different and each represent a substituted or unsubstituted 1-4C hydrocarbon group. n is an integer of 0-5.SELECTED DRAWING: None

The invention relates to a high-temperature proton exchange membrane, in particular to a high-temperature proton exchange membrane based on silica cross-linked polybenzimidazole and a preparation method of the high-temperature proton exchange membrane. The preparation method comprises the following steps: polymerizing 3, 3 '-diaminobenzidine, 4, 4'-diphenyl ether dicarboxylic acid and 5-hydroxyisophthalic acid to form a polybenzimidazole main chain containing an ether bond and a phenolic hydroxyl group, grafting a silane coupling agent on the polybenzimidazole main chain, and finally carrying out membrane formation and acid catalysis treatment to obtain the high-temperature proton exchange membrane based on silica crosslinked polybenzimidazole. A silicon-oxygen network structure is introduced into a polybenzimidazole main chain, so that the phosphoric acid retention rate and the oxidation resistance of the polymer film can be effectively improved, and the service life of the polymer film is prolonged.

A process produces aliphatic monocarboxylic acids and α,ω-dicarboxylic acids or α,ω-dicarboxylic monoesters by electrochemical oxidation of unsubstituted or at least monosubstituted, monounsaturated or polyunsaturated fatty acids or fatty acid esters in the presence of an inorganic or organic nitrate salt in an electrolysis cell in a reaction medium in the presence of oxygen.

The invention relates to the field of polyester materials, and particularly discloses modified polyester with low yellowness value and high glass transition temperature characteristics and a preparation method thereof, and the modified polyester is prepared by taking terephthalic acid, diphenyldicarboxylic acid and fluorenyl aromatic dicarboxylic acid as carboxylic acid monomers, respectively esterifying with ethylene glycol, and carrying out co-polycondensation on corresponding esterification products. According to the present invention, the biphenyldicarboxylic acid with the conjugated aromatic ring structure and the fluorenyl aromatic dicarboxylic acid monomer are selectively introduced to modify the PET, such that the regularity of the polyester chain segment is broken so as to ensure the optical performance of the polyester; the movement of a polyester chain segment is limited so as to improve the Tg value of polyester; and by matching with a novel preparation method, the yellowness value of the polyester material is reduced.

The present invention relates to a composition containing A) 60 to 93 wt. % of at least one aromatic polycarbonate, polyester carbonate or mixtures thereof, B) 2 to 20 wt. % of a polyester on the basis of an aromatic or cycloaliphatic dicarboxylic acid or mixtures thereof and cyclohexane dimethanol and optionally an additional aliphatic diol, and C) 1 to 20 wt. % of at least one phosphorus-containing flame retardant. The invention also relates to a component that contains the composition and to the use of components B and C in the indicated quantities in order to improve CTI and flame retardancy of polycarbonate compositions.

The invention discloses a water body heavy metal ion pollution treatment adsorption filtering membrane and a preparation method thereof, and relates to the technical field of water treatment. When the water body heavy metal ion pollution treatment adsorption filtering membrane is prepared, graphene oxide sequentially reacts with 3-diethylaminopropylamine, tetrabromophenyl porphyrin and N, N-diethyl allylamine, and functionalized graphene oxide is prepared; the preparation method comprises the following steps: reacting cellulose with 4 '-bromo-2, 2': 6 ', 2' '-terpyridyl and maleic anhydride in sequence to prepare modified cellulose; the preparation method comprises the following steps: reacting sodium alginate with propylene oxide to prepare modified sodium alginate; the modified sodium alginate, the modified cellulose, the functionalized graphene oxide, trans, trans-1, 3-butadiene-1, 4-dicarboxylic acid and a photoinitiator are subjected to a reaction, a membrane is prepared, and the water body heavy metal ion pollution treatment adsorption filtering membrane is prepared. The water body heavy metal ion pollution treatment adsorption filtering membrane prepared by the invention has good antibacterial and photocatalytic organic matter degradation capabilities.

A process produces unsubstituted or at least monosubstituted α,ω-dicarboxylic acids and ketocarboxylic acids by electrochemical oxidation of unsubstituted or at least monosubstituted, monounsaturated or polyunsaturated cycloalkenes by electrochemical oxidation in the presence of an inorganic or organic nitrate salt in an electrolysis cell in a reaction medium in the presence of oxygen.

The invention provides a method for producing long-chain dicarboxylic acid and a long-chain dicarboxylic acid product. The method comprises the following steps: inoculating a seed solution of a fermentation strain into a fermentation tank, wherein a fermentation substrate comprises any one or more of fatty acid and derivatives thereof, and alkane; according to the method, green raw materials such as fatty acid and derivatives thereof, plant-based alkane and the like are adopted as substrates to partially or completely replace fossil energy such as petroleum alkane and the like, the product is green long-chain binary acid, and the bio-based content can be regulated and controlled. And the fermentation method provided by the invention can still maintain relatively high yield and conversion rate.

The invention belongs to the technical field of polyester polyol, and particularly relates to high-functionality low-viscosity polyester polyol and a step-by-step synthesis method thereof. Comprising the following steps: (1) adding dihydric alcohol, dicarboxylic acid, a catalyst and an antioxidant into a reaction kettle, heating and vacuumizing, and carrying out esterification and ester exchange reaction to prepare a polyester polyol intermediate; and (2) cooling the polyester polyol intermediate prepared in the step (1), adding polyol into the reaction kettle, and continuously carrying out ester exchange reaction to obtain the high-functionality low-viscosity polyester polyol after the reaction is finished. According to the step-by-step synthesis method, the problems that in the prior art, high-functionality polyester polyol is large in viscosity and low-viscosity products are difficult to prepare are solved, the viscosity of the high-functionality polyester polyol can be effectively reduced under the same raw material system and hydroxyl value conditions through specific raw material selection and process control, and the method is simple in process and easy to implement. The industrial production is convenient.

The invention relates to the field of high polymer materials, and discloses a preparation method and application of high-temperature-resistant transparent modified polyester. The preparation method comprises the following steps: 1) blending 9, 9-di-[(4-phenylphenoxy) dibenzoic acid] fluorene with diacid and dihydric alcohol, and carrying out esterification reaction; and 2) carrying out condensation polymerization on the esterification product to obtain the high-temperature-resistant transparent modified polyester with the glass transition temperature of more than 70 DEG C. According to the invention, 9, 9-di-[(4-phenylphenoxy) dibenzoic acid] fluorene is used as a modification monomer, and is copolymerized with other dibasic acids and dihydric alcohols to synthesize the modified polyester, and the modified polyester has high transparency and still has good mechanical properties and dimensional stability at high temperature. Therefore, the high-temperature-resistant transparent modified polyester is applicable to the application fields of optical films, optical lenses, reflective protective films, optical fibers or liquid crystal displays and the like.

The invention discloses a method for catalyzing the alternating copolymerization reaction of epoxide and cyclic anhydride, which utilizes a composite dicarboxylic acid zinc catalyst to catalyze the alternating copolymerization reaction of epoxide and cyclic anhydride, and comprises the following components in molar ratio: a) a zinc compound; and b) the ratio of the metal hydrogen compound is 1: (0.1-12). The zinc compound is a compound with a general formula of Zn-R (COO) 2, wherein R is C1-C8 alkyl; the metal hydrogen compound is a compound with a general formula of XHY, X is Li, Na, Mg, K, Ca, Be, Sr, Ba, Ra, Fr, Rb or Cs, and Y is 1, 2 or 3. The composite catalyst prepared by the invention is simple in preparation method, is applied to catalysis of alternate copolymerization of epoxide and cyclic anhydride, and has the characteristics of high catalytic activity and low polyether content.

The invention discloses preparation and application of a manganese hydroxylate modified zirconium-based metal organic framework, and belongs to the technical field of wastewater treatment. According to the preparation method, firstly, Mn oxide serves as a dopant, naphthalic acid serves as a frame connector, a zirconium-manganese bimetal organic frame is prepared through a hydrothermal method, and hydroxylation treatment is conducted through an alkali solution; mn replaces Zr atoms on a zirconium cluster to form high charge density with Zr, Mn and Zr can jointly participate in an electron transfer process and an active oxygen generation process to form double active centers, and the catalytic activity of a Fenton-like system is enhanced, so that the oxidative adsorption removal rate of As is remarkably improved. Experimental results show that the As removal rate can still reach 95.1% after five cycles, the targets of oxidative adsorption of As and reutilization are achieved, and the application of the zirconium-based metal organic framework in the field of catalytic adsorption of As is expanded.

The invention provides a thermoplastic polyester elastomer as well as a preparation method and application thereof. The thermoplastic polyester elastomer comprises aromatic dibasic acid residues and aliphatic polyol residues, on the basis that the total molar weight of the aliphatic polyol residues is 100 mol%, the aliphatic polyol residues comprise 66 to 95 mol% of micromolecular diol residues, 2 to 24 mol% of polymer polyol residues and 1.5 to 10 mol% of third polyol residues; the third polyhydric alcohol residues comprise residues derived from a benzotriazole compound and residues derived from a tetramethyl piperidine compound. The thermoplastic polyester elastomer is good in light aging resistance, the surface of a workpiece is not separated out in the processing process and after the thermoplastic polyester elastomer is placed for a long time, and the requirement of automobile interiors for color change of light-color materials after light aging is met.

An object of the invention is to provide a polyester resin with highly reduced gelation, in addition to high moldability, surface smoothness, transparency, mechanical properties, heat resistance, thermal oxidative degradation stability, and chemical resistance. A polyester resin comprising a constituent moiety derived from terephthalic acid as a dicarboxylic acid component and constituent moieties derived from each of ethylene glycol, 1,4-butanediol, and a compound represented by a given structure as an alcohol component, wherein the dicarboxylic acid component comprises from 85 mol % to 100 mol % of terephthalic acid, the alcohol component comprises from 85 mol % to 100 mol % of 1,4-butanediol based on a total amount of ethylene glycol and 1,4-butanediol, and the alcohol component comprises from 0.001 mass % to 5 mass % of the compound represented by the given structure in 100 mass % of the alcohol component.

The invention relates to a carboxylic acid ligand-copper metal organic framework nano material, a preparation method thereof and an injection. The carboxylic acid ligand-copper metal organic framework nano material is of a polycrystal MOF structure formed by connecting carboxylic acid ligands and copper ions through coordinate bonds; the carboxylic acid ligand comprises at least one of dicarboxylic acid and tricarboxylic acid; preferably, the dicarboxylic acid comprises at least one of itaconic acid and fumaric acid, and the tricarboxylic acid comprises at least one of aconitic acid and citric acid; the valence states of the copper ions comprise zero valence, + 1 valence and + 2 valence; preferably, based on the total amount of the copper ions being 100 at%, the total content of Cu0 and Cu + is 85-90 at%, and the content of Cu2 + is 10-15 at%.

The invention relates to the technical field of multi-layer copolyester films, and discloses a high-temperature-resistant antistatic multi-layer copolyester film and a preparation method and application thereof, and the multi-layer copolyester film comprises an ABA three-layer structure obtained through melt co-extrusion; the layer A is prepared from the following raw materials in percentage by mass: 5 to 30 percent of anti-blocking agent master batch and the balance of modified copolyester; the raw material of the layer B is modified copolyester; the modified copolyester is prepared from a binary acid mixture, a dihydric alcohol mixture and a catalyst through an esterification reaction and a condensation polymerization reaction; the binary acid mixture comprises furandicarboxylic acid and 2, 2 '-bifuran-5, 5'-dicarboxylic acid, and the dihydric alcohol mixture comprises ethylene glycol, 2, 2, 4, 4-tetramethyl-1, 3-cyclobutanediol and 1, 4-cyclohexanedimethanol. According to the invention, the modified copolyester is used as a main raw material, and the film is endowed with good temperature resistance in a copolymerization modification manner, and has stable and lasting antistatic performance.

The invention discloses a structure-reversible intervariant metal frame adsorption material and a preparation method and application thereof, and belongs to the technical field of adsorption materials, and the preparation method comprises the following steps: dissolving anhydrous calcium chloride and 2, 5-pyrazine dicarboxylic acid in a mixed solvent, then adding concentrated nitric acid, carrying out a heating reaction, continuing to activate the obtained solid product at 50-420 DEG C for 24 h, filtering, washing, and drying to obtain the structure-reversible intervariant metal frame adsorption material. And realizing structural transformation to obtain the intervariant metal frame adsorption material with the reversible structure. The reversible intervariant metal framework provided by the invention provides a new strategy for research and development of multifunctional MOFs materials, so that the material can adjust the pore characteristics and the three-dimensional space structure according to the temperature change, and the macroscopic adsorption performance is obviously influenced. The preparation process provided by the invention is simple and convenient, and a new strategy is provided for cadmium ion sewage treatment.

The invention relates to the technical field of new material application, and discloses a magnetic bead material for enriching a sulfydryl peptide fragment and a preparation method thereof.The magnetic bead material prepared from micron carboxyl magnetic beads, dodecane dicarboxylic acid dihydrazide and SPSP has a long chemical reaction connecting arm, so that a reaction group has the better freedom degree, the reaction with sulfydryl is better facilitated, and the magnetic bead material can be used for enriching the sulfydryl peptide fragment. The enrichment efficiency is relatively high. When the magnetic bead material is prepared, micron carboxyl magnetic beads and dodecane dicarboxylic acid dihydrazide are based on hydrazine group and carboxyl condensation, the condensation reaction is more selective and more stable, the reaction is carried out under a milder condition, the reaction product is stable, and the reaction efficiency is higher at a lower reaction temperature. Dodecane dicarboxylic acid dihydrazide and SPSP are based on a reaction of N-succinimide and hydrazine, N-succinimide has high specificity to amino-containing molecules, side reactions are reduced, the reaction is generally carried out at room temperature, strong acid and alkali conditions are not needed, and protection of other sensitive groups is facilitated.

4, 4 '-bipyridine (Bpy), 2, 5-thiophenedicarboxylic acid (Tdc), FeCl3. 6H2O, NiCl2. 6H2O, urea and tetrabutylammonium bromide are used as raw materials, a simple hydrothermal-calcination method is adopted to prepare the Fe2O3-coated Ni-MOF composite nanomaterial catalyst, X-ray diffraction (XRD), a scanning electron microscope (SEM) and a N2 adsorption and desorption technology are adopted to characterize a prepared sample, and the electro-catalytic oxygen evolution reaction (OER) activity of the Fe2O3-coated Ni-MOF composite nanomaterial catalyst is tested. Results show that compared with a single component, the activity of the composite nano-material catalyst is greatly improved, especially the composition-optimized Fe2O3-coated Ni-MOF-1 composite nano-material catalyst shows the highest catalytic activity, the composite nano-material catalyst catalyzes OER in 1M KOH, and the overpotential (eta 10) is only 330mV when the current density is 10mA / cm < 2 > and is close to the overpotential 291mV of a noble metal catalyst RuO2.

The invention provides a method for extracting and refining long-chain dicarboxylic acid and a product, and the method comprises the following steps: (1) carrying out heating treatment on fermentation liquor of long-chain dicarboxylic acid to reduce the content of insoluble substances in the fermentation liquor so as to obtain mixed feed liquor in which the dry weight ratio of the insoluble substances is less than 4wt%; (2) filtering the mixed material liquid to obtain filtrate, carrying out acidification crystallization treatment and solid-liquid separation treatment on the filtrate through or without decoloration treatment to obtain a first solid; and (3) refining the first solid. The extraction and refining method provided by the invention can improve the purity and quality of the long-chain dicarboxylic acid product, and the product has large particle size, is simple and easy to operate, and is beneficial to large-scale industrial production.

The present disclosure relates to novel lamotrigine salts, co-crystals, and compositions. In some embodiments, the lamotrigine salt is a lamotrigine dicarboxylic acid salt or hydrate or solvate thereof. In some embodiments, the lamotrigine co-crystal is a co-crystal of lamotrigine and a dicarboxylic acid, or a hydrate or solvate thereof. In some embodiments, the compositions comprise lamotrigine or a salt or co-crystal thereof, or a hydrate or solvate thereof. In some embodiments, the composition is in the form of a powder. In some embodiments, the composition is in the form of a liquid. The present disclosure also relates to methods of preparation and use in medical therapy, for example, for the treatment of a subject with epilepsy or bipolar disorder.

The invention discloses a microporous metal organic framework material, a preparation method and a rare gas separation method, and belongs to the technical field of chemical adsorption separation, the microporous metal organic framework material is constructed by coordination of divalent metal ions, heterocyclic dicarboxylic acid ligands and nitrogen-containing heterocyclic ligands; divalent metal ions and heterocyclic dicarboxylic acid ligands are coordinated to form a two-dimensional polymer, and nitrogen-containing heterocyclic ligands serve as pillared bodies and are coordinated with the two-dimensional polymer to form a three-dimensional frame structure. A microporous metal organic framework material is used as an adsorbent and is in contact with a rare gas mixture, so that high-polarity rare gas is recognized and captured, and separation and purification of the rare gas are achieved. According to the invention, by changing different ligands and functional group substituents thereof, precise regulation and control of a pore chemical electrostatic environment are realized, so that selective separation of rare gases such as xenon / krypton, helium / neon and the like is realized.

The invention discloses a copper-titanium etching solution and a preparation method thereof, and belongs to the technical field of etching solution preparation. The etching solution is prepared from the following components in percentage by mass: 4.5-7.5% of potassium peroxymonosulfate composite salt, 1.2-2.8% of sodium percarbonate, 1.2-2.8% of benzotriazole-2, 3, 4-triazole-2, 3, 4-triazole-2, 3, 4-triazole-2, 3, 4-triazole-2, 3- The cleaning agent is prepared from the following components in percentage by weight: 1.2%-1.8% of 1, 3-dicarboxylic acid, 0.3%-0.8% of 5-aminotetrazole, 0.15%-0.45% of ethylenediamine tetraacetic acid tetrasodium salt, 0.15%-0.45% of hydroxyethylidene diphosphonic acid, 0.15%-0.45% of cocamidopropyl betaine, 0.3%-0.8% of benzotriazole, 0.15%-0.45% of 2-mercaptobenzothiazole, 0.02%-0.08% of poly-N-isopropylacrylamide, 0.7%-1.8% of potassium perchlorate and the balance of ultrapure water. According to the etching solution, the copper-titanium etching rate can be accurately regulated and controlled, back cutting and titanium residues are effectively inhibited, the stability of the etching solution is improved, and the service life of the etching solution is prolonged.

The invention discloses an anti-ultraviolet / salt-spray-resistant polyamide composite material and a preparation method thereof, and relates to the field of engineering plastic processing. The anti-ultraviolet polyamide composite material comprises the following components in parts by mass: 70-94 parts of polyamide resin, 5-20 parts of anti-ultraviolet polyamide master batch and 1-10 parts of polydopamine modified hydrotalcite nanoparticles, the anti-ultraviolet polyamide master batch is prepared from the following components in parts by mass: 55 to 99 parts of polyhexamethylene adipamide salt solution with the mass concentration of 5 to 50 percent, 1 to 50 parts of modified anti-ultraviolet agent salt and 0.3 to 1.5 parts of antioxidant; the modified anti-ultraviolet agent salt is obtained by reacting 5-50 parts of an amino-terminated modified anti-ultraviolet agent compound and 5-50 parts of dicarboxylic acid in absolute ethyl alcohol; the polydopamine modified hydrotalcite nano-particles comprise layered hydrotalcite nano-particles and a polydopamine coating layer on the surfaces of the layered hydrotalcite nano-particles. The anti-ultraviolet / salt-fog-resistant polyamide composite material has lasting and stable anti-ultraviolet performance and salt-fog-resistant performance, meanwhile, the excellent mechanical performance of the polyamide material can be kept, and the anti-ultraviolet / salt-fog-resistant polyamide composite material has high application value.

The invention relates to a method for synthesizing tetrasubstituted ‑1,3‑enedicarboxylic acid, and discloses a method for synthesizing tetrasubstituted ‑1,3‑enedicarboxylic acid. The method comprises the following steps: using 1,3‑enyne and iodide as raw materials, potassium formate as a formate source, DABCO as a hydrogen transfer catalyst, Ir(bpy)2(dtbpy)PF6 as a photocatalyst, and cesium carbonate as a base, introducing CO2 under normal pressure, and obtaining an enedicarboxylic acid compound with an excellent to good yield under room temperature and visible light irradiation for 24 hours. The method has mild reaction conditions, good regioselectivity, and good functional group tolerance, and makes up for many deficiencies of the prior art.

The invention relates to the technical field of mercury removal, in particular to a compound heavy metal chelating agent and a preparation method and application thereof. The preparation method of the compound heavy metal chelating agent comprises the following steps: mixing N-dithio carboxyl-amino phenyl formic acid, a cyclohexyl-3, 5-diene-1, 2-dicarboxylic acid solution, a propionic acid solution and a sodium hydroxide solution, stirring until complete dissolution and standing, then completing evaporative crystallization, and separating and purifying the separated chelating agent. The N-dithio carboxyl-amino phenyl formic acid, the cyclohexyl-3, 5-diene-1, 2-dicarboxylic acid, the propionic acid and a proper amount of sodium hydroxide are mixed to form a compound reagent, the chelating absorption effect on the heavy metal Hg in the natural gas wastewater is better, and the formed chelate is very stable and not easy to decompose.