520 results about "Reactive site" patented technology

The invention relates to the technical field of high-entropy oxide and electrocatalyst synthesis, in particular to a double-phase hollow high-entropy oxide catalyst and a preparation method and application thereof, the double-phase hollow high-entropy oxide catalyst comprises metal elements and non-metal elements, the metal elements comprise ruthenium, nickel, cobalt, iron, manganese and chromium; the non-metallic element is oxygen; the chemical formula of the double-phase hollow high-entropy oxide catalyst is NiCoFeMnCrRuO. The invention further discloses a preparation method of the catalyst. The double-phase hollow high-entropy oxide catalyst has a multi-shell hollow structure, provides a larger specific surface area and exposes a large number of reaction active sites, so that the double-phase hollow high-entropy oxide catalyst has lower overpotential, higher reaction efficiency and good electrochemical stability; meanwhile, the preparation method of the double-phase hollow high-entropy oxide catalyst is simple in process, low in cost, high in repeatability and suitable for industrial mass production, and has a wide application prospect.

The invention discloses a reaction site prediction method and device based on chemical and physical prior driving, and the method comprises the steps: extracting set features through the multi-modal input of a fusion molecular map, an SMILES sequence and a three-dimensional conformation; generating atomic embedding by using a message passing neural network, and calculating a mixed feature fusing a topological path and a three-dimensional distance; combining the key type weight to construct a graph position code of chemical environment correction; injecting the mixed distance and the charge difference into a Transform attention mechanism, and explicitly modeling an inter-atomic long-range electron effect; a model is jointly trained through double tasks of comparative learning and mask prediction, the comparative learning adopts a directional negative sample to enhance generalization, and mask prediction synchronously recovers an atom type and a charge transfer matrix; and finally, injecting quantum chemistry priori constraint attention weights such as a Fuzzy well function, outputting an atomic-scale reaction activity probability, generating a thermodynamic diagram, and realizing high-precision and interpretable active site labeling. According to the method, the drug design and reaction mechanism analysis efficiency can be remarkably improved.

The invention discloses a supported nickel catalyst for preparing 1, 3-propylene glycol through hydrogenation of 3-hydroxypropionaldehyde as well as a preparation method and application of the supported nickel catalyst, and relates to the technical field of catalysts. The modified long-chain multi-carbon inducer is used, and a special long-chain molecular structure and a branched chain group of the inducer can effectively and selectively adsorb and occupy a micropore impregnation site; the preparation method has the beneficial effects that more active component nickel species are obviously promoted to be dispersed in main reaction confinement spaces such as mesopores and macropores and interact with the carrier to form effective active sites, and active component steeping liquor is inhibited from entering micropore channels due to capillary action; the active site failure caused by agglomeration of nickel species in micropores in the subsequent drying and roasting process of the catalyst precursor is avoided, the efficient and directional reaction is ensured, the generation of by-products is greatly reduced, the pressure is relieved for the subsequent product rectification separation, and the final product purity is improved. The catalyst provided by the invention can still keep an excellent catalytic effect when the air speed of a 3-hydroxypropionaldehyde solution is increased to 6.5 h <-1 >.

The invention discloses an MWW molecular sieve and a preparation method thereof, and the preparation method comprises the following steps: (a) mixing an alkali source, water, an aluminum source, a template agent and a silicon source to form a mixture A; (b) adding nano cellulose into the mixture A to form a mixture B, and pretreating, crystallizing and drying the mixture B to obtain the MWW molecular sieve. The preparation method disclosed by the invention is simple and convenient, easy to industrialize and wide in application prospect, and the MWW molecular sieve with the single-layer structure is prepared. The MWW molecular sieve with a single-layer structure can expose more active sites, promotes diffusion and mass transfer, shows excellent performance in many reaction processes, and particularly shows high activity and stability in a reaction with macromolecules as a substrate.

The invention provides a ZIF-derived Co-P catalyst and a preparation method thereof. The catalyst can be used for synthesizing dimethyl carbonate through oxidative carbonylation of methanol. The ZIF-derived Co-P catalyst disclosed by the invention is prepared by roasting a precursor P-doped Zn / Co-ZIF intermediate. Compared with a traditional cobalt-based catalyst, the Co-P catalyst prepared through roasting treatment modification can regulate and control the variety and coordination number of heteroatoms, improve the interaction between metal and a carrier and effectively anchor metal atoms, and meanwhile P atoms can serve as second active sites to assist in improving the adsorption and activation capacity of reactants and intermediate species. In addition, the ZIF generates a hierarchical pore structure in the roasting treatment process, so that the mass transfer and diffusion processes of reactants and products are effectively promoted. According to the Co-P catalyst disclosed by the invention, the methanol oxidative carbonylation reaction activity is remarkably improved, and the catalyst has high stability.

The invention belongs to the field of computational chemistry, and particularly relates to a multi-parameter collaborative dynamic screening method for adsorbed species on the surface of a catalyst. Comprising the following steps that an initial crystal structure is constructed and optimized through VESTA software, and a stable crystal structure model is obtained through density functional theory optimization; integrating working condition parameters such as a solvent, pH and potential, and drawing a Bayer diagram to label adsorption species and a mapping relation; and calculating a zero charge point and capacitance to obtain electrochemical parameters, and determining stable adsorption species under actual reaction through constant potential molecular dynamics simulation. According to the scheme, a deep structure-activity relationship between an active site structure and catalytic activity under a working condition is established through integration of all working condition parameters, labeling of adsorption species by a Boubye diagram, constant potential molecular dynamics simulation and the like; the problems that a systematic method combined with actual working condition parameters is lacked in prediction of the adsorbed substances on the surface of the catalyst, and real adsorbed species are difficult to accurately screen are solved, and accurate capture and efficient screening are achieved.

The invention discloses a zirconium-based MOF material and a preparation method and application thereof, in the zirconium-based MOF material, metal ions are Zr < 4 + >, an organic ligand is ellagic acid, a conditioning agent is gallic acid, and the material has an oxygen vacancy structure and a hierarchical pore structure; the preparation method comprises the following steps: (1) mixing ellagic acid, gallic acid, zirconium oxychloride octahydrate and a solvent, and carrying out solvothermal reaction; and (2) washing and drying the solid after the reaction in the step (1) to obtain the zirconium-based MOF material. According to the invention, renewable and low-cost ellagic acid and gallic acid are respectively used as an organic ligand and a conditioning agent, and an oxygen vacancy structure is constructed in a competitive coordination manner, so that more hydroxyl and unsaturated metal Zr active sites are exposed, the interaction with formaldehyde (HCHO) is enhanced, and meanwhile, the oxygen vacancy structure can be used as an oxygen vacancy catalyst. And the existence of the hierarchical pore structure can effectively promote mass transfer, so that the HCHO adsorption capacity is improved.

The present invention discloses a preparation method and application of a MOF-on-MOF heterojunction metal-organic framework material rich in oxygen defects, belonging to the technical field of electrocatalytic oxygen evolution reaction. The present invention first grows Ni NDC nanosheets in situ on a carrier by a solvothermal method, and then grows Fe BDC nanosheets on the surface of the Ni NDC nanosheets by a solvothermal method to form Ni NDC@Fe BDC ultra-thin nanosheets. This method can synthesize a MOF-on-MOF type metal-organic framework under the premise of lattice mismatch. The synthesized Ni NDC@Fe BDC combines the advantages of multi-component material hybridization, ultra-thin nanosheets and defect induction, which can increase the number of active sites and promote the rapid transfer / redistribution of electrons in the catalytic process. The MOF-on-MOF heterojunction metal-organic framework has good electrocatalytic performance and excellent total water decomposition performance in alkaline oxygen evolution reaction.

The invention discloses a zinc-sulfur co-doped ZIF-67 derivative composite material as well as a preparation method and application thereof, and belongs to the technical field of advanced oxidation. The composite material is prepared through a coordination-substitution-calcination integrated process. The preparation method comprises the following steps: firstly, mixing a cobalt source and an organic ligand in methanol, and introducing a sulfur source to form a cobalt-based precursor; and drying, grinding with a zinc source, and calcining in an inert atmosphere. According to the method, stable cobalt active sites are replaced by isocrystals of zinc, sulfur doping promotes cobalt and peroxymonosulfate to form a weak oxidizing intermediate, and efficient and high-selectivity degradation of organic pollutants is achieved under the condition that a strong free radical path is not needed. The material is stable in structure and high in water quality interference resistance, is suitable for catalyzing peroxymonosulfate to degrade organic pollutants in a water body, and particularly has remarkable advantages in a complex water body.

The invention relates to the technical field of catalysis, in particular to a green preparation process for synthesizing 4 '-chloro-2-aminobiphenyl through a membrane method.A palladium-based catalytic membrane is prepared through an impregnation method, by means of the multi-pore-channel advantage of a ceramic membrane, active components can be well distributed on the surface and in the membrane, contact of a reaction substrate and active sites is promoted, and the catalytic activity of 4'-chloro-2-aminobiphenyl is improved. The reaction effect is enhanced, the reaction efficiency is improved, the preparation process is simple, the preparation environment is mild, and large-scale production can be realized; meanwhile, the 4 '-chloro-2-aminobiphenyl is prepared by adopting a method for carrying out Suzuki-Miyaura coupling reaction by adopting the catalytic membrane, tedious steps in the traditional industry are omitted, compared with a traditional heterogeneous catalyst, the trouble of recovery is avoided, the cost is saved, the harm to the environment is greatly reduced, and compared with the prior art, the 4'-chloro-2-aminobiphenyl has a wide application prospect.

The invention provides a monatomic cobalt-based composite catalyst, a preparation method of the monatomic cobalt-based composite catalyst and application of the monatomic cobalt-based composite catalyst to degradation of antibiotics by activating peroxymonosulfate, and belongs to the technical field of advanced oxidation. The method comprises the following steps: mixing biomass powder and water to obtain a biochar suspension, adding cobalt nitrate hexahydrate into the biochar suspension, centrifuging the mixed solution, collecting residues, and drying to obtain a sample; and pyrolyzing the sample in a protective gas atmosphere, taking out, cooling, washing, and drying to obtain the monatomic cobalt-based composite catalyst. The cobalt-based catalyst prepared by the invention has high specific surface area, abundant pore structures and a large number of active sites, and is beneficial to activation of PMS and degradation of pollutants; the cobalt-based composite catalyst prepared by the method is used for activating peroxymonosulfate to degrade tetracycline, and the removal rate of tetracycline in a solution is greater than 99% after reaction is carried out for 20 minutes under a dark condition.

The invention discloses a sodium metavanadate-based catalyst activity gradient regulation and regeneration system and method, and relates to the technical field of industrial catalyst regeneration, the sodium metavanadate-based catalyst is of a unique layered structure, the sodium metavanadate-based catalyst comprises an outer layer, a middle layer and an inner layer from the surface to the interior in sequence, and active components and doping elements of all the layers are different; the outer layer is doped with high-content sodium metavanadate and manganese oxide, reactant molecules can be quickly adsorbed and activated in the initial stage of the reaction, the manganese oxide can provide additional active sites, reduce reaction activation energy and promote quick start of the reaction, and the middle layer is doped with a proper amount of sodium metavanadate and cerium oxide, so that the reaction is more stable in the process of the reaction. The cerium oxide can adjust migration and conversion of oxygen species on the surface of the catalyst, optimize the reaction path, improve the selectivity of a target product and reduce side reactions, the inner layer is doped with the low-content sodium metavanadate and tungsten oxide, and the structural stability of the catalyst under high-temperature and long-time reaction is maintained by means of the high stability of the tungsten oxide.

The invention discloses a preparation method and application of a catalyst based on pyridine ionic liquid, and belongs to the technical field of catalyst preparation. According to the invention, a hydrolysis reaction of a silane coupling agent is utilized to prepare a silicon oxide nanotube containing a pyridine unit, and then a quaternization reaction is carried out to obtain the catalyst based on the pyridine ionic liquid. The catalyst has a high specific surface area and a rich pore channel structure, exposure of active sites and contact of the active sites and reactants are facilitated, and the catalytic rate is increased. Meanwhile, the silicon oxide nanotube contains hydroxyl, and can cooperate with a pyridine ionic liquid site to catalyze a carbon dioxide cycloaddition reaction. The obtained catalyst can catalyze the reaction of carbon dioxide and an epoxy compound to prepare cyclic carbonate under solvent-free and metal-free conditions, and the catalyst is easy to recover and simple in product purification, and has a good application prospect.

The invention discloses a hydrophobic carbon-based monatomic catalyst and a preparation method thereof. The hydrophobic carbon-based monatomic catalyst comprises a carbon skeleton of a core-shell structure, a metal monatomic active site fixed on the carbon skeleton by forming a coordinate bond with N on the carbon skeleton, and an alkyl chain grafted on the carbon skeleton through a covalent bond. The alkyl chain is grafted through the covalent bond, chemical stable regulation and control of the hydrophobicity of the carbon-based nickel monatomic catalyst are achieved, covalent bond modification avoids the defects of a physical method, long-term stability of hydrophobicity is ensured, and efficient hydrophobic modification is achieved on the premise that monatomic sites are not damaged; a stable three-phase interface is formed on the hydrophobic surface, physical enrichment of CO2 near the catalyst is promoted, mass transfer resistance is reduced, CO2 diffusion is further accelerated through the hollow structure of the carbon skeleton, and the mass transfer capacity is improved.

The invention discloses a copper-cobalt bimetallic catalyst and a preparation method and application thereof. The preparation method comprises the following steps: mixing ZIF-67, a copper source and a solvent, adjusting the pH value to 7.0, stirring, standing, centrifuging, washing and drying to obtain ZIF-67 adsorbed with copper ions, and calcining to obtain the copper-cobalt bimetallic catalyst. Compared with a conventional cobalt-based bimetallic catalyst, the copper-cobalt bimetallic catalyst prepared by the invention has the advantages of large specific surface area, multiple catalytic active sites, high catalytic activity, good structural stability and the like, is a novel catalyst with a novel structure and excellent performance, can efficiently activate peracetic acid and is used for degrading antibiotics; the method can realize deep oxidative degradation of various antibiotics in different water bodies, has the advantages of high reaction system activation rate, high degradation efficiency, wide pH application range, good reusability, low metal leaching amount, no secondary pollution and the like, and is high in use value and good in application prospect.

The invention relates to the technical field of metal organic framework materials (MOF) and isotope separation, in particular to a functionalized metal organic framework material for water / heavy water separation and a preparation method and application thereof. The metal organic framework material is a porous crystal material which is formed by coordination self-assembly of metal ions and V-shaped organic ligands and has a periodic network structure; the V-shaped organic ligand is a V-shaped dicarboxylic acid organic ligand modified by an oxygen-containing functional group designed through topological functionalization. According to the metal organic framework material, through topological functional design of a V-shaped organic ligand, a space confinement channel and a high-density oxygen active site are integrated in the same MOF material, and an ideal model system is provided for identification of water isotopes; according to the metal organic framework material, the framework structure flexibility, the pore channel confinement effect and the molecular recognition capability can be synergistically regulated and controlled, so that efficient recognition and separation of water / heavy water are realized.

The invention provides a preparation method, a product and application of an acid site / carrier decoupled metal-acid multifunctional catalyst, and belongs to the technical field of biomass energy utilization. According to the preparation method, a metal active site is provided by non-noble metal Ni, a neutral material h-BN is taken as a carrier, and a Ni element is reduced and loaded on h-BN under an alkaline condition by adopting a liquid phase reduction method, so that the Ni / h-BN catalyst is prepared; and then heteropoly acid is used for providing an acid site, the acid site is loaded on a Ni / h-BN catalyst through an impregnation method, and Ni-HSiW / h-BN is prepared. According to the present invention, by flexibly regulating and controlling the acid site (loaded or unloaded heteropolyacid), the required product can be selectively obtained when the obtained catalyst is used for catalyzing the lignin derivative hydrodeoxygenation reaction, and by regulating and controlling the temperature, the time and other parameters of the hydrodeoxygenation reaction, the high selectivity on the reaction product can be provided.

The invention discloses a preparation method of a sulfonic acid type covalent organic framework material and a preparation method of 5-hydroxymethylfurfural. The material is prepared by carrying out covalent condensation reaction on a monomer containing a sulfonic acid group precursor and a connecting ligand of a skeleton through a hot solvent method, and the catalyst has the characteristics of high crystallinity, large specific surface area, ordered pore structure, high sulfonic acid group density and uniform distribution. The preparation method is simple, convenient, efficient, mild in condition and high in yield. Compared with a traditional lewis acid catalyst for preparing 5-hydroxymethylfurfural through fructose dehydration, the material has the advantages of being uniform and adjustable in porosity, higher in active site, capable of promoting fructose hydrolysis and the like, efficient conversion can be achieved, side reactions and product transition polymerization are inhibited, and better industrialization prospects are shown.

The invention discloses an S-type three-dimensional carbon nitride / copper sulfide nanosphere heterojunction as well as a preparation method and application thereof, and belongs to the field of antibacterial application of nano materials. The three-dimensional porous carbon nitride not only can increase photocatalytic active sites, but also can improve close contact with copper sulfide. The copper sulfide nanospheres and the three-dimensional porous nanosheets construct an S-shaped heterojunction, and efficient separation of photo-induced electrons and hole pairs can be driven under the action of a built-in electric field, band edge bending and coulomb force. The S-type three-dimensional carbon nitride / copper sulfide nanosphere heterojunction can generate more active oxygen species to inactivate bacteria through a photocatalysis-Fenton-like reaction; in addition, the photothermal effect of copper sulphide has a certain auxiliary sterilization effect. Under the conditions of visible light irradiation and trace hydrogen peroxide, the inactivation rates of the S-type three-dimensional carbon nitride / copper sulfide nanosphere heterojunction on staphylococcus aureus and escherichia coli are up to 99.5% and 99.7% respectively, and meanwhile, the S-type three-dimensional carbon nitride / copper sulfide nanosphere heterojunction has a remarkable treatment effect on wounds infected by staphylococcus aureus.

The invention discloses preparation of superfine PdInBi alloy nano-particles and application of the superfine PdInBi alloy nano-particles in an electrocatalytic oxidation reaction. The superfine alloy nanoparticle catalyst is prepared by adopting a simple solvothermal method, the size of the obtained catalyst is about 4nm, and the catalyst is uniformly dispersed. In addition, due to the nanoscale particle size, the Pd-based catalyst has more proportion of exposed Pd atoms, so that the electro-catalytic performance of the Pd-based catalyst is improved. The precious metal alloying is an effective way for improving the reaction activity and selectivity. According to the multi-metal-based catalyst, the dosage of precious metal can be remarkably reduced, agglomeration of the precious metal is prevented, all the elements regulate and control the electronic structure through the synergistic effect, meanwhile, combination of different metal atoms can form new active sites on the surface of the catalyst, and therefore the activation energy of the reaction is reduced. Compared with a Pd / C catalyst, the catalyst provided by the invention has higher catalytic performance on ethylene glycol oxidation reaction.

The invention relates to an A-site high-entropy double perovskite anode material and a preparation method and application thereof. The chemical general formula of the anode material is (Ln < 1 > < 0.2 > Ln < 2 > < 0.2 > Ln < 3 > < 0.2 > Ln < 4 > < 0.2 > Ln < 5 > < 0.2 >) A 'B2O5 + delta (wherein delta is greater than or equal to 0 and less than or equal to 1). Wherein Ln1 to Ln5 are five different lanthanide rare earth elements and jointly occupy the A site, and the A site elements are any five of Sm, Pr, Nd, La, Gd, Eu, Er, Dy, Te, Yb, Y and Sc; the A'site is composed of any two elements of Ba, Sr and Ca; and the B site is Co. According to the invention, the double perovskite structure can be effectively stabilized, the number of catalytic active sites of an OER reaction is increased, the TEC of a cathode is effectively reduced, the electro-catalysis ORR reaction activity is increased, the performance of hydrogen production by electrolysis of water of a single cell is improved, and the output stability of the cell is effectively enhanced.

The present invention belongs to the technical field of covalent organic frameworks, and particularly relates to a method for preparing a single-crystalline vinylidene-bridged covalent organic framework. The method for preparing a single-crystalline vinylidene-bridged covalent organic framework comprises: mixing a single-crystalline imine-linked covalent organic framework, an active monomer, a catalyst and an organic solvent until uniform, and then performing a substitution reaction, wherein the substitution reaction is one or more of an aldol condensation reaction, a Knoevenagel condensation reaction, and a Claisen-Schmidt reaction. The single-crystalline vinylidene-bridged covalent organic framework having good stability, rich active sites, high photoelectric activity and a high conjugation degree is obtained by means of a substitution reaction of the single-crystalline imine-linked covalent organic framework and the active monomer under the action of a catalyst.

The method comprises the following steps: firstly, putting a catalyst into a reaction system, and introducing a nitrogen source and a hydrogen source; wherein the catalyst comprises a carrier and a heterojunction material loaded on the surface of the carrier; and then illuminating, heating and applying an electric field to the reaction system at the same time, so that the N = N bond or N = O bond in the reaction system is adsorbed and cracked, and the ammonia is catalytically synthesized. The heterojunction material has a metal property, a thermoelectric property and heterojunction interface double active sites, and photoproduction local oscillation photoproduction of the metal heterojunction is precisely enriched at the interface double active sites under the thermoelectric synergistic effect, so that the charge density of the interface double active sites is remarkably improved; a traditional activation mode of single nitrogen atom in a single site adsorption N = N bond or N = O bond is changed, heterojunction interface charge-rich double-site synergistic adsorption and splitting of the N = N bond or N = O bond are realized, and a nitrogen source activation energy barrier is reduced, so that the yield of synthesis ammonia is remarkably improved.

The invention discloses a tetracycline detection method based on defect PCN-224-Pt NPs with high oxidase activity, and belongs to the technical field of ecosystem and public health detection. The method comprises the following steps: firstly synthesizing PCN-224, then synthesizing PCN-224 (at) Pt NPs, and finally carrying out tetracycline colorimetric sensing detection. According to the invention, the PCN-224 (at) Pt NPs is synthesized by growing platinum nanoparticles (PtNPs) on the surface of a PCN-224 nanocube in situ. By introducing defect engineering into a metal structure of PCN-224, vacancy defects and active sites are formed, so that generation of small-particle-size and uniformly dispersed platinum nanoparticles is realized, the load rate of PtNPs in the PCN-224-Pt NPs nano-enzyme is remarkably improved, and the oxidase activity of the PCN-224-Pt NPs nano-enzyme is further enhanced. As the PCN-224 has a porphyrin metal structure, the PCN-224 shows excellent tetracycline adsorption capacity, active sites of platinum are effectively covered, and the catalytic activity of the PCN-224-Pt NPs nano-enzyme is inhibited. Experiments show that the limit of detection (LOD) of the method is 0.04 [mu] M.

The invention relates to the technical field of mycotoxin rapid detection, in particular to an electrochemical luminescence sensor for citrinin detection and a detection method of the citrinin. A sensing substrate of the sensor is prepared by loading platinum nanoclusters (Pt NCs) on a NiCo-LDH / MXene composite substrate through an in-situ growth strategy; the high conductivity of MXene and the LDH confinement effect are utilized to synergistically promote three-dimensional exposure of Pt active sites, the efficiency of generating active oxygen through electro-catalysis is remarkably enhanced, and a light-emitting signal is improved. And a CRISPR / Cas12a system is further integrated, so that a regulation mechanism of recognition-cutting-signal de-suppression is realized, and food matrix interference is effectively avoided. And a new technology is provided for monitoring the fungaltoxin by combining a dual enhancement mechanism of material catalytic optimization and enzymatic signal amplification.

The invention relates to the technical field of medicines, in particular to a preparation method of semeglutide, which comprises the following steps: by optimizing a coupling sequence, firstly connecting a main peptide chain compound 1 with a side chain compound 5 without carboxyl protection, and then performing subsequent coupling with a dipeptide structure compound 6 with high steric hindrance, thereby obtaining the semeglutide. The problem of excessive modification caused by coexistence of a plurality of active sites in a traditional route is effectively avoided, especially for coupling difficulty brought by the structure of a compound 6, the types of a condensation reagent and a side-chain compound 5 are optimized, dipeptide carboxyl of the compound 5 is remarkably activated, amido bonds can be efficiently formed by the compound 5 and a compound 2 under the mild condition, and the compound 6 can be efficiently synthesized. In the path of synthesizing the compound 3 from the compound 1, one-pot operation is realized, and the reaction liquid in each step can be used for the next step without refining, so that the reaction time and the consumption of raw materials are reduced, and the connection efficiency and selectivity of key steps are greatly improved.

The invention discloses a green synthesis process of non-steroidal loxoprofen sodium, and relates to the field of loxoprofen sodium synthesis. A water / organic two-phase free radical bromination and functionalized Pd-Ru / NH2-ZIF-8 catalysis one-step hydrogenation degreasing-tert-butyl ester removal path is adopted. The catalyst is modified by a thiol ligand and cooperates with a chiral inducer to construct a Pd-Ru bimetallic active site, so that the product purity and the product yield are effectively improved, and the catalyst can be repeatedly used. The method is environment-friendly and efficient in process and suitable for industrial application.

The invention provides a preparation method of glycine, which comprises the following steps: preparation of a supported catalyst: dissolving an active component precursor in water, sequentially adding a catalyst carrier and a sodium hydroxide solution, uniformly mixing, and drying to obtain the supported catalyst; 2, mixing monoethanolamine with water, adjusting the pH value to be alkaline, adding the supported catalyst in the step 1, reacting, and filtering after the reaction to obtain a glycinate solution; and acidifying the glycine salt solution by using a hydrochloric acid solution, and performing crystallization separation to obtain glycine. A metal organic framework catalyst is introduced, the specific surface area reaches up to 6000 m < 2 > / g or above, the porosity exceeds 80%, meanwhile, the high mechanical strength is achieved, the evenly-distributed pore channel structure can effectively promote adsorption and diffusion of reactant molecules, an active precursor can be efficiently loaded on MOF active sites in the scheme, and the catalyst has the good application prospect. And in the catalysis process, the structure is stable and is not easy to damage, so that the catalysis efficiency is remarkably improved, the yield and purity of glycine are further improved, and the carrier can be repeatedly used.

The application provides a Sn-doped Fe-N-C catalyst, a preparation method and application thereof. The catalyst comprises a carrier and Sn atoms and Fe atoms supported on the carrier, and the carrier is an N-doped carbon material. The application dopes the p-block metal Sn with stronger electronegativity into the Fe-N-C catalyst, forms an electron-withdrawing environment around the FeN4 site, reduces the electronegativity of the FeN4 site, and weakens the adsorption strength of the FeN4 site on the oxygen reduction intermediate. Meanwhile, the metal Sn is weaker in reactivity with hydrogen peroxide produced by the reaction of oxygen via a two-electron process than Fe, reduces the concentration of free radicals produced by the reaction, improves the stability of the carrier and active sites, and can effectively prevent the shedding of Fe. The application uses the catalyst as a cathode catalyst of a proton exchange membrane fuel cell, is low in cost, and can simultaneously meet the requirements of high catalytic activity and good stability.

This invention relates to the field of catalyst technology, and discloses an inorganic-organic composite catalyst and its application, as well as a method for synthesizing acryloyloxyethyltrimethylammonium chloride. The catalyst preparation method includes: reacting a hydrolyzed siloxane coupling agent with titanium tetrachloride at a pH value less than or equal to 1.5. The hydrolyzed siloxane coupling agent is R-Si(OH)3, where R is a C8-C20 alkyl group, and the molar ratio of the hydrolyzed siloxane coupling agent to titanium tetrachloride is 0.07-0.15:1. This catalyst ensures synergistic effects of solubility and active sites, and exhibits high catalytic performance even at low dosages. In the synthesis of acryloyloxyethyltrimethylammonium chloride, it effectively improves the reaction efficiency and selectivity of acryloyloxyethyltrimethylammonium chloride, further increasing the yield and purity of acryloyloxyethyltrimethylammonium chloride.