1357 results about "Metallic catalyst" patented technology

The invention relates to the technical field of polyurethane production, in particular to a polyurethane super-hydrophobic foam composite material for packaging and a preparation method thereof. The polyurethane super-hydrophobic foam composite material for packaging is prepared by reacting a component A and a component B according to a mass ratio of 100: (31.7-46.5), wherein the component A comprises polyether polyol X with high molecular weight and high activity, polymer polyol, a chain extender, a cross-linking agent, an organic metal catalyst, a tertiary amine catalyst, a foam stabilizer, a foaming agent, a flame retardant, inorganic filler and the like, and the component B is isocyanate modified by polyether polyol Y with high functionality. An ester bond, a rigid benzene ring group and a Si-O-Si chain segment are introduced into a polyether polyol molecular chain segment to improve the internal soft segment structure and chemical crosslinking density of the polyurethane foam, and the prepared super-hydrophobic polyurethane foam not only has excellent hydrophobicity and high temperature resistance, but also is low in density and good in mechanical property.

In order to solve the problems of low yield, complex process and difficulty in purification in the existing preparation method of benzodifurandione, the invention provides a preparation method of benzodifurandione, which comprises the following operation steps: synthesis of benzodifurandione: mixing hydroquinone, paraformaldehyde, a transition metal catalyst and a ligand under an acidic condition to obtain a mixture A; introducing CO, reacting at the temperature of 120-150 DEG C to obtain a mixture containing benzodifuran diketone, cooling and filtering to obtain a benzodifuran diketone solid; and purification: purifying the benzodifuran diketone solid to obtain the benzodifuran diketone. The preparation method provided by the invention is simple and convenient to operate, the obtained monomer benzodifuran diketone raw material is high in purity and stable in quality, and large-scale production of polymers can be realized.

The invention relates to the technical field of supported metallocene catalysts, in particular to a supported metallocene catalyst additive as well as a preparation method and application thereof. The supported metallocene catalyst additive has the following structure: # imgabs0 #, R is selected from C1-C10 alkyl groups, R1 and R3 are selected from alkyl groups and adamantyl groups and are located at ortho-para positions of-OH, R2 is selected from C1-C10 alkyl groups and cycloalkyl groups, and R'is selected from alkyl groups. The additive can greatly retain the catalytic activity and copolymerization performance of a metallocene catalyst, improve the metal loading capacity and catalytic activity, and reduce the dosage of a traditional cocatalyst MAO.

The invention discloses a nano silicon dioxide loaded ruthenium-copper bimetallic catalyst as well as preparation and application thereof, and belongs to the technical field of acetylene hydrogenation reaction catalysts. A strong electrostatic adsorption method is adopted, nano silicon dioxide is used as a carrier, the pH of a solution is higher than the isoelectric point of the carrier through adjustment of ammonia water, and the carrier is negatively charged; in ammonia water, Cu and Ru respectively form positively charged metal complexes, and metals are anchored on the surface of the carrier under the action of strong electrostatic adsorption to prepare the atomic-scale dispersed ruthenium-copper bimetallic catalyst for acetylene selective hydrogenation reaction. When the prepared catalyst is used for catalyzing an acetylene hydrogenation reaction and the reaction temperature exceeds 170 DEG C, the acetylene conversion rate can reach 100%, and the ethylene selectivity is 90%-100%. And the catalyst has excellent stability, and can keep activity for a long time without obvious deactivation phenomenon.

The invention relates to the technical field of polypeptide cyclization methods, in particular to a preparation method for constructing a phage display cyclopeptide library based on phthalic dicarboxaldehyde, which comprises the following steps: carrying out click chemical reaction on phthalic dicarboxaldehyde (OPA) and lysine and cysteine in an unprotected peptide sequence under a neutral or alkaline condition to form cyclopeptide; constructing a phage cyclic peptide library on the basis of the reaction property that the OPA molecule is efficiently biocompatible with sulfydryl and amino groups; a polypeptide library containing cysteine and lysine is displayed on a bacteriophage, the polypeptide library is cyclized by utilizing OPA (o-phthalaldehyde), and a cyclic peptide ligand with specific binding is screened out aiming at a target protein. In the strategy of performing polypeptide cyclization by using o-phthalaldehyde, it is found that o-phthalaldehyde has good reaction activity with sequence peptide containing cysteine and lysine, reaction conditions are simple and mild, and the o-phthalaldehyde has good biocompatibility. The reaction system does not need organic solvents or metal catalysts and is suitable for biological systems.

The invention discloses a bipolar membrane and a preparation and use method thereof, the bipolar membrane comprises a cation exchange membrane, the cation exchange membrane comprises a base material and a cation exchange layer arranged on at least one surface of the base material, and sulfonic acid type ionic liquid is added in the cation exchange layer; the metal catalyst layer is arranged on one surface of the base material, so that the cation exchange layer and the metal catalyst layer are respectively arranged on two opposite surfaces of the base material; the anion exchange layer is arranged on the surface of the metal catalyst layer and comprises quaternized imidazole derivatives and quaternary ammonium type ionic liquid, and the quaternary ammonium type ionic liquid accounts for 25% or above of the weight of the imidazole derivatives. The method has the advantages of high acid and alkali production concentration, stable membrane structure, stable performance and the like, and is suitable for long-term and stable preparation of high-concentration acid and alkali.

The invention belongs to the technical field of carbon nanotube purification, and provides a carbon nanotube purification method. The method comprises the following steps: placing unpurified carbon nanotube raw powder in a fixed bed Joule thermal reactor; introducing weak oxidizing gas, heating to enable the temperature of the reaction zone to reach 100-400 DEG C, generating first Joule heat at the carbon nanotube raw powder, and removing an impurity carbon layer coating the surfaces of the metal catalyst particles; heating to enable the temperature of the reaction zone to reach 200-700 DEG C, generating second Joule heat at the carbon nanotube raw powder, and removing impurity carbon on the surface of the carbon nanotube; and mixing the treated carbon nanotube raw powder with acid, and removing the metal catalyst particles. According to the present invention, the weak oxidation gas is adopted as the reaction gas, the electric field is introduced under the external low temperature condition to perform the stepped purification, and the Joule heat is selectively generated on the different types of the impurity carbon and the metal catalyst micro-region so as to achieve the effect of selectively removing the multiple types of the impurity carbon under the mild condition.

The invention provides a method for producing succinate by using maleic anhydride airflow. The method comprises the following two reaction processes: absorbing esterified maleic anhydride airflow by using RR1R2COH alcohol as an absorption solvent to prepare butenedioic acid ester, and hydrogenating the butenedioic acid ester under the action of a metal catalyst to prepare the succinate. According to the technical scheme, the alcohol substances are used as the solvent and the esterifying agent, succinic acid ester can be prepared by carrying out absorption esterification on maleic anhydride gas flow and directly hydrogenating the absorption liquid without separation, raw materials are cheap, the process is short, the system is simple and convenient, investment is saved, material consumption and energy consumption are low, and the production cost is low.

The invention discloses an application of a single-metal Co (at) N-C nanotube with high C and N contents. The Co (at) N-C nanotube is used for a zinc or magnesium metal air battery positive electrode material catalyst. The application of the oxygen reduction catalyst in a primary zinc-air battery, a primary magnesium-air battery and a secondary zinc-air battery is realized. The oxygen reduction catalytic material is characterized by being a monometallic catalyst, and shows relatively high energy density and power density in a metal battery. The half-wave potential of the prepared single-metal catalyst Co (at) NC-1Co (at) NC-1 is 0.85 V, and the half-wave potential exceeds the half-wave potential of commercialized 20% Pt / C; the limit diffusion current density Jd is 5.44 mA cm <-2 >, which is equivalent to that of commercial 20% Pt / C. The power density of a primary zinc air battery taking Co-coated NC-1 as the oxygen reduction catalyst is 202 mW cm <-2 >, and the maximum energy density is 928 Wh kg <-1 > Zn, which is higher than that of a Pt / C-based zinc metal air battery. The catalyst has the advantages of easily available raw materials, simple preparation and low cost, and has potential commercial application value.

The invention discloses a polyester-carbon dioxide based polycarbonate-polyester triblock biodegradable elastomer and a preparation method of the polyester-carbon dioxide based polycarbonate-polyester triblock biodegradable elastomer. The polyester-carbon dioxide based polycarbonate-polyester copolymer with a triblock structure is obtained by initiating and catalyzing epoxide, carbon dioxide and high-activity tetrachlorophthalic anhydride to be copolymerized through a metal catalyst or Lewis acid-base pair. The polycarbonate chain segment formed by the long-chain branch epoxide 1 and carbon dioxide has a low glass transition temperature (Tg1lt; -20 DEG C); and a polyester chain segment formed by tetrachlorophthalic anhydride and short-chain branch epoxide has a high glass transition temperature (Tg2 is greater than or equal to 100 DEG C), so that the triblock copolymer has two obvious glass transition temperatures, and has the thermoplastic processability of plastic and the high elasticity of rubber due to the unique microphase separation structure.

The invention provides a synthesis method of bio-based poly (ethylene 2, 5-furandicarboxylate) (poly (ethylene 2, 5-furandicarboxylate) for short) and performance application of the bio-based poly (ethylene 2, 5-furandicarboxylate). According to the method, 2, 5-furandicarboxylic acid (FDCA) derived from renewable resources and ethylene glycol (EG) are used as main raw materials, and the high-molecular-weight PEF is prepared through microwave-assisted esterification-polycondensation reaction under the action of a metal catalyst. The prepared PEF has excellent thermal mechanical property and gas barrier property, the glass transition temperature is about 58.6 DEG C, the melting temperature is about 187.4 DEG C, and the thermal decomposition 18% weight loss temperature exceeds 400 DEG C. The PEF material can be biologically degraded under the industrial composting condition, and the degradation speed is higher compared with that of traditional petroleum-based PET polyester. The PEF provided by the invention is suitable for the fields of food packaging films, beverage bottles and fiber materials, has the advantages of biodegradability, heat resistance stability and high barrier property, can partially replace polyethylene glycol terephthalate (PET) and other petrochemical plastics, and meets the requirements of sustainable development.

The application belongs to the technical field of batteries, and particularly relates to a silicon-carbon negative electrode material and a preparation method and application thereof. The method comprises the following steps: preparing a porous carbon fiber membrane loaded with a metal catalyst; preparing a dispersion solution of a nano-silicon-based material, and distributing the nano-silicon-based material into the porous carbon fiber membrane to obtain a composite porous carbon fiber membrane; and performing thermal chemical vapor deposition on the composite porous carbon fiber membrane in an inert atmosphere containing a carbon source, growing carbon nanofibers and vertical graphene on the surface of the composite porous carbon fiber membrane, and obtaining a silicon-carbon negative electrode material. Through a synthesis route of thermal chemical vapor deposition (T-CVD), the synthesis process is optimized, and a multi-level three-dimensional network structure of carbon nanofibers and vertical graphene is constructed to enhance the electrical conductivity of the silicon-carbon negative electrode material, accelerate carrier transmission, improve the interface contact performance between the silicon-based material and the carbon material, improve the loading capacity of the nano-silicon-based material, inhibit the volume expansion of the nano-silicon-based material, and improve the structure and cycle stability of the nano-silicon-based material.

The invention discloses a method for preparing a g-C3N4 loaded Fe and Mn bimetallic catalyst with high efficiency and low cost, and belongs to the technical field of catalysts. Manganese ferrite is adopted as a bimetal source, a melamine one-step calcination method is combined, synthesis of g-C3N4 and loading of Fe and Mn are synchronously achieved, manganese ferrite is decomposed into FeOx and MnOx nanoparticles in the calcination process, the FeOx and MnOx nanoparticles and nitrogen sites of g-C3N4 form strong coordinate bonds, metal atomic-scale dispersion can be achieved, and metal ion migration is inhibited; through the bimetallic synergistic effect of Fe and Mn, the oxidation-reduction capacity of the catalyst can be remarkably improved; through the unique thermal decomposition characteristic, the bimetallic synergistic effect and the strong chemical bonding of the manganese ferrite and g-C3N4, the efficient exposure of active sites, the remarkable improvement of the oxidation reduction capacity and the effective inhibition of metal dissolution are realized, and the preparation method also has the advantages of high efficiency, low cost and small secondary pollution risk.

To provide a manufacturing method for a catalyst ink that can reduce the sedimentation of catalyst particles within the catalyst ink.SOLUTION: There is provided a manufacturing method for a catalyst ink, the catalyst ink Including: catalyst particles including a metal catalyst supported on a carbon carrier; a solvent; and an ionomer. The method includes a step of stirring and mixing, by using beads having a bead diameter of 2 mm or less, the catalyst particles, the solvent, and the ionomer, thereby, an average particle diameter of the catalyst particles becomes 2.2 μm or less after the stirring and mixing.SELECTED DRAWING: Figure 1

The invention belongs to the technical field of catalyst preparation, and particularly relates to a preparation method and application of a humic acid-based carbon material supported bimetallic catalyst. The catalyst is prepared from 0.1 weight percent to 10 weight percent of Pt, 0.4 weight percent to 10 weight percent of second metal (Fe, Ni, Co or Mo) and 80 weight percent to 99.5 weight percent of a humic acid-based carbon material carrier. The preparation method comprises the following steps: grinding humic acid and an accelerant, roasting at high temperature to obtain a humic acid-based carbon material, and loading the second metal (Fe, Ni, Co or Mo) and Pt on the surface of the humic acid-based carbon material by a step-by-step impregnation loading method. The catalyst can efficiently catalyze hydrogenation of 5-hydroxymethylfurfural (5-HMF) in a tetrahydrofuran solvent to prepare 2, 5-dimethylfuran (2, 5-DMF). The humic acid-based carbon material is used as a carrier, the catalyst is simple in preparation process, low in cost and high in catalytic activity, efficient conversion of the biomass-based platform compound 5-HMF can be achieved under mild reaction conditions, and the catalyst has remarkable industrial application value.

The invention discloses a method for preparing a chiral furanone ester derivative, which comprises the following steps: adding a metal catalyst into a solvent, sequentially adding a carboxylic acid compound I or a carboxylic acid compound II and a butene lactone compound III, introducing inert gas, stirring, post-treating and purifying to obtain a chiral furanone ester compound IV; the palladium catalysis system is composed of palladium salt and a chiral ligand V, and the chiral ligand has a structure shown in a formula V.

The invention provides a topological chiral semimetal catalyst for oxygen electrocatalysis and a preparation method and application thereof.The topological chiral semimetal catalyst is a supported catalyst and comprises a carrier, an active component and guest metal, the carrier is selected from one of Vulcan XC-72R, Vulcan XC-72, Ketjenblack and carbon nanotubes, the active component is Pt, and the guest metal is selected from one of Vulcan XC-72R, Vulcan XC-72, Ketjenblack and carbon nanotubes. The invention discloses a topological chiral semi-metal material with a space group of P213, the topological chiral semi-metal material comprises an active component and a guest metal, the active component is a carrier, the dispersion size of the active component in the carrier is 2-4 nm, the guest metal is selected from one or two of Ga, Al, Ba, Ge, Bi, Sb, Eu, Fe, Cr, Sr and Mg, and compared with the prior art, the topological chiral semi-metal material (PtGa, PtMg, PtAl, BaGePt, BiTePt, BiSbPt, EuGePt, FeSbPt, CrSbPt and SrGePt) with the space group of P213 shows excellent performance in the oxygen reduction reaction of a fuel cell cathode. Compared with the current advanced PtC catalyst, the precious metal content is low, the stability is good, the yield of the by-product H2O2 is only 0.5%, and the PtC catalyst has a good application prospect in oxygen electro-catalysis.

The invention discloses a preparation method of a 1-(aryl sulfuryl) bicyclo [1.1. 0] butane compound, which comprises the following steps: reacting a compound 1 serving as a raw material with trisubstituted propane and an alkaline reagent in a reaction solvent in an air-isolated environment under the action of an organic catalyst and a metal catalyst at the temperature of-78 to 200 DEG C for 1 to 48 hours to obtain the 1-(aryl sulfuryl) bicyclo [1.1. 0] butane compound. And obtaining a compound 2 after complete reaction. The key raw materials in the synthesis route are cheap and easy to obtain, the reaction conditions are mild, the operation is convenient, the process safety is high, the selectivity is high, the yield is high, the product purity is high, the production cost is greatly reduced, and the production requirement of the product at the ton level or above can be fully met.

The invention discloses a bimetallic CO-SCR catalyst and a preparation method and application thereof, and belongs to the technical field of catalytic materials. The bimetallic CO-SCR catalyst comprises the following raw materials: an X metal precursor, a Y metal precursor, a ligand and a carrier, x metal in the X metal precursor is precious metal; y metal in the Y metal precursor is non-noble metal. According to the bimetal CO-SCR catalyst, coordination of bimetal X and Y is utilized, high oxygen resistance of the X-Y bimetal catalyst is achieved through the steric hindrance effect by means of the synergistic effect of ligands, the preparation method is simple, and an important reference basis is provided for preparation of the catalyst for CO selective catalytic reduction of NOx (CO-SCR) in the oxygen-containing environment.

The present invention designs a method for preparing a key intermediate of synthetic boceprevir, namely a chiral pyrrolidone derivative, through catalytic hydrogenation. Specifically, it involves the use of substrate chiral induction by adjusting and modifying the substituents of the substrate to achieve the asymmetric catalytic hydrogenation of dihydropyrrolidone by a metal catalyst. The advantages of the present invention are that the process route is simple and feasible, the yield is high, the cost is low, and it is easy to industrialize production, etc.

The invention relates to a regeneration treatment method and application of a degradable high polymer material, and the regeneration treatment method comprises the following steps: degrading the degradable high polymer material in a system in which an organic nonmetal catalyst and a water-containing solvent exist to obtain a degradation product; wherein the degradable high polymer material comprises one or more of a polyester material and a polycarbonate material; the organic nonmetal catalyst is selected from one or more of diphenyl phosphate, binaphthol phosphate and organic alkali. By adopting the specific organic non-metal catalyst, efficient degradation of the degradable high polymer material can be realized, the degradation speed is high, the conversion rate is high, the reaction yield is high, and the cost is low; degradation products can be effectively utilized again as valuable chemicals.

The invention belongs to the technical field of carbon fibers, and particularly relates to polyacrylonitrile-based carbon fibers as well as a preparation method and application thereof. According to the preparation method provided by the invention, the tensile modulus of the polyacrylonitrile-based carbon fiber is improved, the tensile modulus of the polyacrylonitrile-based carbon fiber is 200-590 GPa, and the tensile strength of the polyacrylonitrile-based carbon fiber is 2.4 GPa or above. Through gasification reaction of the metal catalyst, formation of a graphite-like structure of the carbon fiber and improvement of regularity of the carbon fiber are promoted, elements except carbon elements are removed, through low-temperature graphitization, a graphite layer plane is further oriented along a fiber axis, the rigidity of a molecular chain is increased, and the modulus is improved; and meanwhile, the problems of large broken filament amount and high energy consumption during graphitization of the carbon fibers are effectively relieved. The polyacrylonitrile-based carbon fiber provided by the invention has high tensile modulus, is suitable for occasions with high mechanical property requirements, such as aerospace, automobile materials, sports equipment or wind power generation, and has wide application prospects.

The invention relates to 6-methyl nicotine glycollate and a preparation method thereof, an atomization matrix, a buccal product and an electronic atomization device. The preparation method of the 6-methylnicotine glycollate comprises the following steps: mixing 6-methylnicotine, glycollic acid and a metal catalyst for reaction to obtain a reaction solution containing the 6-methylnicotine glycollate; and carrying out physical adsorption treatment on the reaction liquid to prepare the 6-methyl nicotine glycolate. 6-methylnicotine and glycollic acid react under the action of a metal catalyst, so that the conversion rate of a reaction substrate can be effectively promoted, and residues of the reaction substrate are effectively reduced; the obtained reaction liquid is further subjected to physical adsorption treatment, so that the residual catalyst in the reaction liquid can be effectively removed, and the prepared 6-methyl nicotine glycolate has less heavy metal residue.

The invention provides a copolymerization type epoxy modified emulsified asphalt material for an asphalt pavement adhesive layer and a preparation method of the copolymerization type epoxy modified emulsified asphalt material. The copolymerization type epoxy modified emulsified asphalt material is obtained by mixing modified asphalt and water and then performing high-speed shearing, the modified asphalt comprises the following raw materials in parts by weight: 100 parts of matrix asphalt, 20 parts of an oxidizing agent, 1-2 parts of phosphoric acid, 120-240 parts of polyether polyol, 0.6-2 parts of hydrogen, 4-7 parts of a metal catalyst, 8-24 parts of isocyanate, 2-3.2 parts of an organic metal catalyst and 20-48 parts of epoxy resin. The long-chain polyether polyol is used as a hydrophilic group, so that the emulsification difficulty of the modified asphalt can be effectively reduced, and self-emulsification of the asphalt is realized; the unsaturation degree of the modified asphalt is reduced through hydrogenation reaction, the influence of external environment factors such as water, oxygen and high and low temperatures is reduced, the weather resistance of the asphalt is improved, and the service life of the adhesive layer is prolonged; the epoxy resin is grafted on modified asphalt molecules, so that the cohesive strength and modulus of the modified asphalt can be effectively improved, the tensile strength is far higher than 0.8 MPa of conventional emulsified asphalt, and the service life is prolonged.

The invention belongs to the field of furfuryl alcohol hydrogenation, and particularly relates to a catalyst for preparing 1, 2-pentanediol from furfuryl alcohol as well as a preparation method and application of the catalyst. The catalyst for preparing 1, 2-pentanediol from furfuryl alcohol comprises a composite oxide carrier and a metal catalyst attached to the composite oxide carrier, the composite oxide carrier comprises an oxide core and magnesium oxide attached to the oxide core; the oxide inner core is selected from one, two or three of TiO2, CeO2 and Al2O3; the metal catalyst is Pt or Pt and doped metal, and the doped metal is selected from at least one of Pd and Ru. A novel catalyst carrier design is adopted, the selectivity of the catalyst to 1, 2-pentanediol is further improved, the selectivity of the catalyst to 1, 2-pentanediol reaches 65% or above, and when a double-doped metal form is adopted, the selectivity of 1, 2-pentanediol reaches 80% or above.

The invention discloses a carbon nanotube quasi-catalyst as well as preparation and application thereof, and relates to the technical field of synthesis of carbon nanotube catalysts. A metal catalyst precursor salt, an oxide carrier precursor salt and a complexing agent are mixed to prepare a precursor solution, the colloidal crystal microsphere template is soaked in the precursor solution, and the quasi-catalyst can be obtained after suction filtration, drying and low-temperature heat treatment. When the quasi-catalyst is used for preparing the carbon nano tube, dangerous reducing gas such as hydrogen is not needed, and the carbon nano tube powder which is small and uniform in diameter, excellent in conductivity and easy to disperse can be efficiently prepared on a large scale under the conditions of low carrier gas flow rate and low reaction temperature. The quasi-catalyst and the preparation technology thereof have remarkable technical advantages and cost benefits, and have wide application prospects.

The invention provides a metal Ru catalyst as well as a preparation method and application thereof, and particularly, the metal Ru catalyst is prepared by using a specific carbon source and a ruthenium source as precursors through a simple one-step method. The method is simple in process, low in cost and high in controllability, the obtained metal Ru catalyst has excellent seawater electrolysis activity and stability, the overpotential (mV) shown under 10 mA cm <-2 > under the real seawater condition is 39 mV which is far lower than the overpotential (53 mV) shown under 10 mA cm <-2 > of commercial Pt / C, and the metal Ru catalyst can be applied to the cathodic hydrogen evolution reaction of seawater electrolysis.

The invention provides a negative-electrode-free sodium ion battery current collector, application thereof and a negative-electrode-free sodium ion battery, and relates to the technical field of batteries. The negative-electrode-free sodium ion battery current collector provided by the invention comprises a base material and a coating coated on the surface of the base material, the coating comprises porous nitrogen-doped carbon particles and a binder; the porous nitrogen-doped carbon particles are loaded with fluorine-containing sodium salt and a metal catalyst, and the surfaces of the porous nitrogen-doped carbon particles are coated with polymers. According to the current collector, in-situ construction and dynamic repair of NaF-rich SEI are promoted through the core-shell structure design, long-term, uniform and stable deposition of sodium ions on the current collector can be achieved, the coulombic efficiency of a negative-electrode-free sodium battery is improved, and the cycle life of the negative-electrode-free sodium battery is prolonged.

The invention relates to the technical field of carbon nanotubes, and particularly discloses a purification method of a carbon nanotube. The purification method of the carbon nano tube comprises the following steps: (1) weighing a carbon nano tube crude product and various raw materials, (2) adding the carbon nano tube crude product and a surfactant into deionized water, and carrying out ultrasonic dispersion to obtain a dispersion liquid, (3) carrying out gradient centrifugation on the dispersion liquid, and taking an upper-layer suspension liquid, and (4) mixing hydrochloric acid, nitric acid and the suspension liquid, and treating the carbon nano tube to obtain the carbon nano tube. (5) treating the carbon nano tube by dilute acid, mildly oxidizing the carbon nano tube by using a low-concentration hydrogen peroxide solution, and then placing the carbon nano tube in a magnetic field to adsorb magnetic impurities, (6) carrying out cross-flow filtration by using a polycarbonate microfiltration membrane and collecting the treated carbon nano tube, and (7) annealing the treated carbon nano tube by using inert gas and freeze-drying to obtain the purified carbon nano tube. According to the purification method, the metal catalyst, amorphous carbon and graphite impurities can be efficiently removed, and meanwhile, the integrity of the tube wall of the carbon nano tube is kept.

The invention belongs to the technical field of preparation of nano noble metal catalysts, and relates to a preparation method of a doped carbon-based nano noble metal catalyst. Phytic acid doped polyaniline is prepared through chemical oxidative polymerization, a nitrogen and phosphorus co-doped carbon carrier is obtained through pyrolysis under the nitrogen atmosphere, gold and palladium bimetal is loaded through a metal colloid adsorption method, the doped carbon-based nano noble metal catalyst is obtained, the introduced doped element phosphorus has anchoring and dispersing effects on noble metal, and the noble metal is more stable in performance. The activity of the catalyst is remarkably improved by introducing a trace amount of second component metal palladium. The catalyst prepared by the invention is simple in synthesis method, high in activity, good in selectivity and excellent in cycling stability, is suitable for preparing parachloroaniline by hydrogenation of parachloronitrobenzene, and has a relatively wide application prospect.