1413 results about "Active center" patented technology

The invention discloses a multi-component covalent organic framework material for producing hydrogen peroxide based on photocatalysis and a preparation method and application thereof.The preparation method comprises the steps that a catalyst is added into turbid liquid containing an organic monomer, styrene, etherified boron trifluoride, 2, 3-dichloro-5, 6-dichloro-p-benzoquinone and an organic solvent, the mixture is mixed to be uniform, then the mixture is frozen and subjected to a reaction under vacuum after exhausting, and the multi-component covalent organic framework material is obtained; the multi-component covalent organic framework material for producing hydrogen peroxide based on photocatalysis is obtained. The material has the characteristics of adjustable structure height, abundant active centers, good porosity and the like, can be recycled for multiple times, and is a good catalyst for H2O2 production.

The invention provides a stable multivalent metal surface doped ruthenium oxide catalyst, a preparation method thereof and application of the stable multivalent metal surface doped ruthenium oxide catalyst in a proton exchange membrane water electrolysis device, and belongs to the technical field of catalysts and preparation thereof. According to the prepared multivalent metal such as molybdenum, niobium, tungsten, tantalum and chromium doped ruthenium oxide catalyst, the active center electronic structure is effectively stabilized due to the flexible valence change of the multivalent metal in the oxygen evolution process, meanwhile, a surface layer can be constructed through surface doping, separation of the active center Ru and lattice oxygen is effectively inhibited, and the stability of the catalyst is improved. The prepared catalyst shows excellent catalytic activity and electrochemical stability in an acidic oxygen evolution reaction, has the advantages of low cost and good catalytic stability, and in addition, can stably operate under relatively high current density as a proton exchange membrane electrolyzed water anode catalyst.

The invention relates to a Fe monatomic nano-enzyme as well as a preparation method and application thereof. The preparation method of the Fe monatomic nano-enzyme comprises the following steps: dispersing poly-polyphenol spheres in water, adding ferric trichloride, stirring for 10-14 hours, centrifuging, drying, carbonizing, and pickling to obtain the Fe monatomic nano-enzyme. According to the Fe monatomic nano-enzyme as well as the preparation method and the application thereof, the poly polyphenol spheres and the ferric trichloride are taken as raw materials, the Fe monatomic nano-enzyme with different distances between adjacent active centers can be prepared, the preparation method is simple, the cost is low, and the reaction conditions are mild.

The invention discloses a novel mercaptan removal catalyst as well as a preparation method and application thereof, the catalyst takes potassium-containing solution modified activated carbon as a carrier and one or a combination of more of CH3COOCs, CH3COOK, Cs2CO3 and Rb2CO3 as an active component, and the mass ratio of the active component substance to the modified activated carbon is 3-5%. The preparation method comprises the following steps: (1) modifying activated carbon by using a potassium-containing solution with the concentration of 15-20%, soaking the activated carbon for 2-4 hours by using the potassium-containing solution, then cleaning the activated carbon by using deionized water until the pH value is weakly alkaline, and drying the activated carbon for later use; (2) carrying out vacuum drying on the modified activated carbon at a certain temperature, and dipping a certain amount of active component-containing solution at 20-60 DEG C for 4-12 hours; and (3) carrying out vacuum drying on the active carbon impregnated with the active component, and roasting under the protection of N2 to obtain the mercaptan removal catalyst. The preparation method is simple, the prepared mercaptan removal catalyst has the characteristics of large specific surface and pore volume and the like, and compared with existing patents, the mercaptan removal catalyst is more favorable for maintaining the active center of the catalyst, maintaining the activity stability of the catalyst and improving the mercaptan removal rate.

The invention is applicable to the technical field of biological detection, provides a fluorescence immunochromatography detection method based on monatomic nano-enzyme enhancement, and particularly relates to two application forms: in the first form, a detection signal enhanced fluorescence immunochromatography detection card and a sample diluent containing a monatomic nano-enzyme are involved; in the second form, the invention relates to a fluorescence immunochromatography detection card with enhanced detection signals, and a sample pad of the detection card is obtained by soaking a sample pad treatment solution containing a monatomic nano-enzyme solution. The two application forms both relate to a monatomic nano-enzyme solution, and the solution is composed of monatomic nano-enzyme, bio-enzyme composite microspheres, a protective agent, a surfactant, a thickening agent and a preservative. The monatomic nano enzyme is composed of an atomic-scale dispersed metal active center and a carrier material. When the method is used for detecting myocardial and inflammatory markers, the limit of quantitation can reach the pg / mL level, the detection linear range can span three orders of magnitude, and the clinical examination use requirements can be met. The kit can be applied to rapid quantitative detection of myocardial and inflammatory markers, has the advantages of high sensitivity, rapidness, convenience and high efficiency, and provides an auxiliary diagnosis basis for early screening of myocardial infarction, heart failure and infection related diseases.

The invention discloses a carbon nitride-based composite material as well as a preparation method and application thereof. The carbon nitride-based composite material comprises a non-metal doped carbon nitride carrier and a noble metal, wherein the noble metal exists in the carrier in an element doping form and / or is loaded on the carrier in an oxide form; the precious metal is one or more of Pt, Pd, Au and Ru, and the nonmetal is one or more of P, S and I. According to the carbon nitride composite material disclosed by the invention, noble metal is utilized to modify carbon nitride, the number of surface active sites is increased, the electron and chemical structures of an active center are adjusted, and meanwhile, generation and migration of photo-generated charges are promoted. Meanwhile, the surface of the carbon nitride composite material is modified by non-metallic elements, so that adsorption and activation of reactant H2O molecules are effectively promoted. The catalyst disclosed by the invention is simple in preparation process, good in repeatability and easy for large-scale production.

The invention belongs to the technical field of polyfluorosiloxane synthesis, and provides a low-by-product polyfluorosiloxane controllable synthesis method which comprises the following steps: carrying out anionic ring opening polymerization on D3F by adopting a binary organic catalytic system, weakening the strong nucleophilicity of an active center based on hydrogen-bond interaction and steric effect, and inhibiting the occurrence of chain back-biting side reaction, so as to obtain the low-by-product polyfluorosiloxane. The polyfluorosiloxane with low content of by-product DnF (n is greater than or equal to 4), controllable structure and narrow molecular weight distribution is prepared. The polyfluorosiloxane with low byproduct content is catalyzed by the binary organic catalyst, the synthesis method is simple, the operation is convenient, the reaction condition is mild, the catalyst has good stability, large-scale production is easy, and further development of the polyfluorosiloxane in the field of high-end and harsh oil-resistant sealing materials can be promoted.

The invention relates to the technical field of catalysts, in particular to a dehydrogenation catalyst precursor, a dehydrogenation catalyst and a preparation method and application of the dehydrogenation catalyst precursor. According to the dehydrogenation catalyst precursor, a sulfur-modified magnesium-aluminum mixed oxide is used as a carrier, and a Pt metal cluster is used as an active center; wherein the carrier is a mixed-state metal oxide with a layered hydrotalcite structure, a spinel structure and a near-crystalline synergistic structure. A magnesium-aluminum mixed oxide can be prepared by introducing a precursor of alkali metal magnesium into an aluminum oxide precursor, a layered structure or a spinel structure similar to hydrotalcite can be formed by regulating and controlling the calcination temperature, and by combining carrier surface regulation and control modification, the capability of regulating and controlling the interaction between metal and a carrier can be improved, and the performance of the catalyst is improved. Therefore, the active center of the cluster is maintained, and the acid-base property of the surface of the carrier is effectively modulated, so that carbon deposit is reduced, and the activity and stability of the catalyst are improved.

The invention discloses a method for preparing furfuryl amine by reductive amination of biomass-based furfural, which comprises the following steps: adding furfural, a catalyst, ammonia water and a solvent into a closed reaction kettle in proportion, replacing air in the reaction kettle with high-purity hydrogen, and reacting in an oil bath pan for a period of time to obtain a target product furfuryl amine, the nano-catalyst provided by the invention is a nitrogen-doped porous hollow carbon sphere loaded nano bimetallic catalyst, takes noble metal and non-noble metal as a metal active center together, and has adjustability of macroscopic size and microstructure at the same time; the method has the advantages of simple reaction system, mild conditions, no pollution to the environment, high efficiency, energy conservation, low cost, few byproducts, high yield, high selectivity and the like, the furfural is efficiently converted into furfuryl amine at low temperature and low pressure within a short time, the used heterogeneous catalyst is stable and easy to recover, a new thought and direction are provided for enterprise production and scientific research, and the method is suitable for industrial production. The method has great significance on development and utilization of biomass-based furfural.

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 discloses a supported ozone catalyst for printing and dyeing wastewater treatment and a treatment process, and relates to the technical field of wastewater treatment, the supported ozone catalyst comprises an environmental response type porous medium, an active center and a biological enzyme modification layer; the environment-responsive porous medium is based on poly (N-isopropylacrylamide) grafted and modified mesoporous alumina, the initial aperture of the mesoporous alumina is 10-15nm, the grafting rate of poly (N-isopropylacrylamide) is 12-20%, and an active center is composed of a transition metal active center and quantum dots modified on the transition metal active center. The biological enzyme modified layer is obtained by carrying out deep biological modification on the surface of the catalyst by using laccase with oxidation-reduction activity. According to the invention, an environment-responsive porous medium is constructed by grafting mesoporous alumina with poly (N-isopropylacrylamide), so that the problems that a traditional fixed-aperture catalyst is low in mass transfer efficiency and poor in adaptability to working conditions, and the pollutant release efficiency is difficult to effectively improve under different temperature and pH conditions are solved.

The invention discloses an enzyme immobilization method based on charge directed crosslinking, and belongs to the technical field of enzyme immobilization. The method sequentially comprises the following steps: reacting an enzyme with a modifier containing an anionic group to generate an electronegative modified enzyme; dissolving a protonated amino carrier in an acidic buffer solution to form a first solution, and dispersing a dissociation anion group-containing carrier and a modification enzyme in an alkaline buffer solution to form a second solution; mixing the two solutions, and constructing a gel network immobilized enzyme through electrostatic crosslinking; and finally, strengthening the gel network by using a multivalent metal ion solution. Directional anchoring of the enzyme in the gel is achieved through charge matching, the network stability and the enzyme microenvironment are synchronously optimized in combination with metal ion coordination, use of a covalent cross-linking agent is avoided in the whole process, conformation damage of an enzyme active center is avoided, the activity retention rate, the operation half-life period and the substrate mass transfer efficiency of the immobilized enzyme are remarkably improved, and the immobilized enzyme has good application prospects. The method is suitable for efficient immobilization of industrial enzymes such as beta-glucosidase, and has high biocompatibility and industrial potential.

The invention relates to the technical field of preparation of VOCs catalytic oxidation catalysts, in particular to a reticular spherical B-MnO2 catalyst based on a B-Ov-Mn active center and a preparation method and application of the reticular spherical B-MnO2 catalyst. The B-MnO2 catalyst is prepared from delta-MnO2 serving as a basic component, a B-O-Mn structure formed by doping B into the delta-MnO2, and an asymmetric oxygen vacancy B-Ov-Mn active center formed on the basis of the B-O-Mn structure, compared with the existing MnO2 catalyst, the B-MnO2 catalyst prepared by the preparation method disclosed by the invention is formed by connecting a plurality of nanosheets to form a net-shaped ball, so that the B-MnO2 catalyst has a high specific surface area; moreover, by constructing an asymmetric oxygen vacancy B-Ov-Mn active center, the catalyst can effectively promote the adsorption and activation of H2O and enhance the electron transfer between H2O molecules and the catalyst, so that water vapor contained in actually discharged VOCs waste gas and water vapor contained in the environment can be quickly converted into active hydroxyl groups and participate in catalytic oxidation reaction, and the catalytic oxidation effect is improved. Therefore, the inhibition effect of H2O molecules in a traditional MnO2 catalyst is converted into the promotion effect, and the MnO2 catalyst has good market competitiveness.

The invention discloses a preparation method and application of a CoNiNOC diatomic electrocatalyst for an electro-Fenton system. The preparation method of the catalyst comprises the following steps: firstly, preparing an oxygen-doped cobalt monatomic catalyst (CoNOC) through a temperature gradient pyrolysis and pickling process, and then preparing an oxygen-doped diatomic catalyst (CoNiNOC) by introducing a Ni site into a precursor and using a similar process. The loading capacity of metal active sites is improved by introducing Ni sites, and the electronic structure of an active center is further regulated and controlled, so that the 2e-ORR activity is improved by 15%, the H2O2 selectivity reaches 96% or above, and the stability is 100 h or above. The invention also discloses an application of the catalyst as a heterogeneous electro-Fenton catalyst in degradation of antibiotics, and a CoNiNOC cathode not only can efficiently degrade TC, but also has higher degradation efficiency, TOC degradation rate and kinetic rate constant for various organic antibiotics.

The invention belongs to the technical field of water treatment, and discloses an oxygen-containing functional group modified cobalt-based carbon nanotube as well as a preparation method and application thereof. The preparation method comprises the following steps: mixing and stirring functionalized carbon nanotubes, cobalt salt, cyanuric acid, melamine and a solvent, and then performing centrifugal separation, washing and drying to obtain a precursor; calcining the precursor in a protective atmosphere, and then pickling to obtain the oxygen-containing functional group modified cobalt-based carbon nanotube. Cobalt nitrate is used as a cobalt source, cobalt exists in the form of ions, in the calcining process, cobalt is embedded into a carbon nano tube by means of nitrogen of melamine, cobalt monoatoms exist, cobalt clusters are generated, oxygen-containing functional groups and the cobalt clusters have a regulation and control effect on a charge structure of an active center of the cobalt monoatoms, and the oxygen-containing functional groups and the cobalt clusters have a regulation and control effect on the active center of the cobalt monoatoms. The electric charge density of a cobalt monatomic active center is weakened together, and the binding energy to an intermediate OOH is regulated and controlled, so that the material is a 2e--ORR electrocatalyst with high activity and high selectivity.

The invention belongs to the technical field of environmental catalytic materials and pollutant control, and particularly relates to a Ni-coated NiS < 2 >-coated MoS < x > / NF composite catalyst and a preparation method and application thereof. According to the preparation method of the Ni-coated NiS2-coated MoSx / NF composite catalyst provided by the invention, the Ni-coated NiS2-coated MoSx / NF composite catalyst with a self-supported metal / crystalline / amorphous heterojunction is constructed by virtue of a collaborative strategy of directional self-assembly and internal Ni source and water dispersion, and meanwhile, the activation efficiency of peroxymonosulfate (PMS) can be remarkably improved by combining an Ni-Mo bimetal active center, so that the activation efficiency of the Ni-coated NiS2-coated MoSx / NF composite catalyst is improved. The problems that an existing catalyst is limited in active site and poor in structural stability are solved, the excellent capacity of activating PMS to remove antibiotics is shown, therefore, efficient degradation of antibiotic pollutants is achieved, and the catalyst has wide application prospects in antibiotic wastewater treatment.

The invention relates to the technical field of nano materials and biological medicines, in particular to black phosphorus-loaded monatomic nano enzyme as well as a preparation method and application thereof. According to the monatomic nano-enzyme loaded with the black phosphorus, the monatomic nano-enzyme loaded with the black phosphorus takes a black phosphorus nanosheet as a carrier, and a metal simple substance is anchored on the surface of the carrier; wherein the metal elementary substance comprises any one of iron, cobalt and manganese. A metal active center is anchored on a black phosphorus nano-carrier, the catalytic activity of monatomic nano-enzyme and the photo-thermal conversion performance of a black phosphorus nano-material are effectively combined, the anti-tumor effect is jointly enhanced through chemical kinetic catalysis and photo-thermal, in addition, a loaded black phosphorus degradation product is mainly phosphate and has biological safety, and the application prospect is broad. The toxicity problem of the traditional nano-enzyme can be solved; the wide application is facilitated.

The invention discloses a double transition metal / chitosan-based carbon aerogel composite material and a preparation method and application thereof.The method comprises the steps that a nitrogen source and transition metal salt are added into a hydrochloric acid solution of chitosan, stirred, dissolved and evenly dispersed to prepare a mixed solution, the mixed solution is subjected to freeze drying, and the double transition metal / chitosan-based carbon aerogel composite material is obtained. Chitosan aerogel containing transition metal and a nitrogen source is prepared; the transition metal salt is any two of ferric salt, cobalt salt and nickel salt; the chitosan aerogel containing the transition metal and the nitrogen source is placed in a methanol solution of 2-methylimidazole, after vibration treatment and drying, the chitosan aerogel is placed in a nitrogen atmosphere to be subjected to heat treatment, and the double-transition-metal / chitosan-based carbon aerogel composite material is prepared. The preparation method is simple and reasonable in design, the prepared material has good specific surface area and porosity, the formed metal-nitrogen double active center effectively improves the adsorption performance of the material, and the material has good catalytic performance.

The invention belongs to the technical field of biological medicine, and particularly relates to application of anethomycin in preparation of medicine for inhibiting cysteine protease activity. The invention discovers that anethomycin has the function of inhibiting the activity of virus cysteine protease, especially 3C or 3CL protease, for the first time. Molecular docking proves that anethomycin can effectively bind to the catalytic activity center of Senecavirus (SVA) 3C protease. An in-vitro FRET enzyme activity experiment proves that the inhibition rate of 50 [mu] M of anethomycin on SVA 3C protease reaches up to 88.5%. Cellular level experiments show that the anethomycin can significantly inhibit replication of SVA viruses, shows broad-spectrum antiviral activity on various viruses such as encephalomyocarditis viruses (EMCV), porcine reproductive and respiratory syndrome viruses (PRRSV) and porcine deltacoronaviruses (PDCoV), and is low in cytotoxicity and high in selectivity index (SI).

The invention provides an MXene-derived bimetallic composite material as well as a preparation method and application thereof, and relates to the technical field of catalysts. In the MXene-derived bimetallic composite material provided by the invention, a 3D ordered pore structure provides a channel for organic pollutant molecules and H2O2 to transfer mass to a catalytic active center in the material; tiO2 and the MCuFe-MOF generate photo-induced electrons, a TiO2 / Ti3C2Tx Schottky junction and a MCuFe-MOF / Ti3C2Tx Schottky junction promote separation and transfer of charges, and Fe < 3 + > / Fe < 2 + > circulation is accelerated; the synergistic effect of a redox pair between iron and copper in the MCuFe-MOF is shown as a copper-iron bimetal oxide or a copper-iron bimetal organic framework and the like, interface electron transfer can be accelerated, rapid reduction of Fe < 3 + > and Cu < 2 + > is promoted, the Fenton reaction efficiency is improved, and the photo-Fenton catalytic activity is excellent.

The invention discloses a catalyst for directly producing green aromatic hydrocarbon from biomass synthesis gas, and a preparation method and application thereof, and belongs to the field of aromatic hydrocarbon production. The catalyst for directly producing the green aromatic hydrocarbon from the biomass synthesis gas comprises a zeolite molecular sieve and a transition metal modified Fe-based oxide M1M2-FeOx, the mass ratio of the M1M2-FeOx is 10-80%, and the mass ratio of the zeolite molecular sieve is 20-90%; m1 and M2 are transition metals; in the catalyst, transition metal is utilized to modify iron-based metal, so that various CO2 activation sites are formed, and CO2 adsorption activation is promoted; meanwhile, the iron-based metal active center and the zeolite molecular sieve acid center are matched with each other, so that the catalyst can be used in a reaction system for directly preparing the aromatic hydrocarbon from the biomass synthesis gas, and the catalyst has relatively high conversion rate and aromatic hydrocarbon selectivity in preparation of the aromatic hydrocarbon from the carbon dioxide-containing biomass synthesis gas, and has a good industrial application prospect.

The invention belongs to the technical field of organic synthesis and carbene catalysts, and particularly relates to a bridged double-center carbene catalyst ligand as well as a preparation method and application thereof. The structure of the bridged double-center carbene catalyst ligand is as shown in a formula I: # imgabs0 #, in the formula I, R1, R3, R4, R5, R6, R7, R8, R9 and R10 are respectively and independently selected from any one of H, i-Pr, CH3, Cl, F and NC; n is equal to 1-9; n is selected from any one of Cl and Br. Compared with a carbene catalyst ligand used in the past, the bridged double-center carbene catalyst ligand provided by the invention has double active centers, so that the double-center carbene catalyst ligand can be used for preparing the double-active-center carbene catalyst ligand, and the double-active-center carbene catalyst ligand can be used for preparing the double-active-center carbene catalyst ligand; and by carrying out ligand exchange with a carbene catalyst precursor with a single active center, the active center can be aggregated, so that the high-activity carbene catalyst with double centers is obtained, and higher reaction activity and atom economy are achieved.

The invention discloses a double transition metal doped graphene catalyst and application thereof, the double transition metal doped graphene catalyst is of a hexagonal crystal system structure, and the space group is P6 / mmm; the composition form of the active center is Cu2C3N3, Nb2C3N3, Ta2C3N3, Rh2C6, Rh2C3N3 and Rh2N6, the hydrogen evolution free energy of the active center is-0.03 eV,-0.09 eV, 0.10 eV, 0.12 eV,-0.21 eV and 0.06 eV respectively, the metal binding energy of the active center is-4.53 eV,-8.60 eV,-8.03 eV,-6.13 eV,-7.11 eV and-5.62 eV respectively, the metal forming energy of the active center is-0.54 eV,-1.94 eV,-0.06 eV,-0.64 eV,-1.62 eV and-0.13 eV respectively, and the active center has good catalytic activity, structural stability and preparation feasibility and is used for

The invention relates to the technical field of super-hydrophobic materials, and particularly discloses a super-hydrophobic coating spraying liquid, a preparation and construction method thereof and a super-hydrophobic coating. The super-hydrophobic coating spraying liquid provided by the invention is prepared from the following components: nano SiO2 which is modified by a silane coupling agent containing amino / alkoxy and a silane coupling agent containing long fluorine chain / long-chain alkane step by step, microcapsules which are sequentially modified by the silane coupling agent containing amino / alkoxy and a dispersing agent for the second time, and a solvent which is added into the microcapsules, and a thermosetting resin. The nano SiO2 and the microcapsules which are subjected to multiple modification have good hydrophobicity, and nano metal particles loaded in the microcapsules form an anti-algae active center of the super-hydrophobic coating. And the super-hydrophobic coating prepared by using the super-hydrophobic coating spraying liquid organically combines hydrophobicity and an anti-algae active center together, so that an efficient and long-acting anti-algae effect can be realized, and the problems of short pollution flashover prevention time and poor algae removal performance of the existing super-hydrophobic coating are solved.

The invention discloses a magnesium oxide supported catalyst, a preparation method and application in VOCs (volatile organic compounds) purification, and belongs to the field of volatile organic compound catalytic purification. Magnesium oxide is used as a carrier of the catalyst, and two modified materials are supported, one is a double-active-center material anchoring nickel single atoms and ruthenium clusters in a porous carbon-nitrogen framework, and the other is a double-active-center material anchoring nickel single atoms and ruthenium clusters in a porous carbon-nitrogen framework; and the other one is a defective carbonitride MXene intercalated hydroxyapatite nanosheet, and lanthanum oxide can be added as a cocatalyst. The preparation method comprises the following steps: sequentially loading the two modified materials on the magnesium oxide carrier, and carrying out ultrasonic dispersion, stirring, centrifuging, drying, calcining and the like, so that the active component and the carrier form strong interaction. According to the catalyst, through the synergistic effect of double active centers and the structural advantages of the modified material, the catalytic oxidation efficiency and stability of VOCs are remarkably improved, and the catalyst is suitable for purification treatment of industrial waste gas and volatile organic compounds in indoor air.

The invention discloses a nitrogen atom-doped carbon material loaded superfine metal nano-cluster catalyst as well as preparation and application thereof, and belongs to the field of hydrogen production by electrolysis of water. According to the preparation method, UIO-66 (Ce) with the surface rich in mesoporous and microporous structures is prepared by using a soft template and is used as a precursor, and then the precursor is subjected to carbonization and acid pickling treatment to obtain the three-dimensional nitrogen-doped porous carbon spheres with high specific surface area. The rich hierarchical porous structures on the surface of the carbon material can effectively limit the aggregation of metal active centers in high-temperature reduction and HER reaction processes, and the long-term stability of the catalyst is improved. And due to the extremely high specific surface area, more metal active centers can be loaded, so that the catalytic activity is improved. Experiments show that nitrogen doping can effectively regulate and control the electronic structure of an active center, and the catalytic activity and stability of the catalyst are improved.

The invention relates to the technical field of transition metal catalysts, in particular to a transition metal / alkali metal bimetallic monatomic catalyst for catalyzing acetylene hydrochlorination reaction and a preparation method and application of the transition metal / alkali metal bimetallic monatomic catalyst. After dipping in an alkali metal nitrate solution, the alkali metal is firstly converted into a metal oxide through two-stage calcination, and then the metal oxide is converted into a super-strong alkali metal monatomic material containing a high defect site. And dipping the alkali metal monatomic catalyst in a transition metal salt solution to obtain the transition metal / alkali metal bimetallic monatomic catalyst. Transition metal monatomic serves as a main active center, alkali metal monatomic serves as a super alkali auxiliary, the microenvironment of active sites is greatly improved, the adsorption capacity of the transition metal sites to reactants is enhanced, meanwhile, carbon deposition side reaction can be inhibited, and synergistic catalysis between transition metal and alkali metal monatomic is achieved; the catalyst shows high catalytic activity and stability on acetylene hydrochlorination reaction.

The invention discloses a copper-nickel monatomic catalyst based on an MXene carrier and a preparation method and application thereof, and belongs to the technical field of catalysts.The copper-nickel monatomic catalyst comprises the MXene carrier, a copper-nickel monatomic active component is loaded on the MXene carrier, and the MXene carrier is coated with a nitrogen-doped carbon layer; wherein the content of the copper-nickel monatomic active component is 0.2-1.5 wt%, and the molar ratio of copper to nickel in the copper-nickel monatomic active component is (1: 0.3)-(1: 1.2); and the content of the nitrogen-doped carbon coating layer is 7-10 wt%. The copper-nickel monatomic catalyst does not contain toxic chromium metal, an MXene / copper-nickel monatomic / nitrogen-doped carbon layer ternary composite system is adopted, a few-layer MXene carrier provides rich surface active sites, copper-nickel monatomic active components are anchored through chemical adsorption, a dehydrogenation active center of copper atoms and a cyclization active center of nickel atoms have a synergistic effect, and the catalytic activity of the copper-nickel monatomic catalyst is improved. The oxidation resistance and the stability of the catalyst are remarkably improved through coating of the nitrogen-doped carbon layer, the technical bottlenecks of low activity, short service life and heavy pollution of a traditional catalyst are overcome, and an efficient solution is provided for green synthesis of lactone.

The invention discloses a catalyst for catalyzing diethylene glycol to prepare N-methylmorpholine and a preparation method of the catalyst, and belongs to the field of catalysts. The catalyst for catalyzing diethylene glycol to prepare N-methylmorpholine is composed of uniformly distributed Ni and Cu particles and a NiCuXY oxide solid solution carrier, and the catalyst is prepared by roasting and reducing a NiCuXY mixed hydroxide precursor in a hydrogen atmosphere; wherein X and Y are selected from any one of Al, Zr, Ce, Cr, Ti, Mo and Mg; and X and Y are different. According to the invention, the interface synergistic effect of a NiCu metal active center and a NiCuXY solid solution carrier is utilized; the catalyst disclosed by the invention is simple in preparation method, relatively low in cost, mild in reaction condition, low in energy consumption and beneficial to being applied to an industrial production process.

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