508results about How to "High catalytic activity" patented technology

The invention discloses a composite catalyst for a peracetic acid activation system and a preparation method and application thereof, and relates to the technical field of advanced oxidation water treatment. The preparation method of the catalyst comprises the following steps: preparing an aqueous solution of a cobalt source as a precursor solution; adding a manganese source into the precursor solution to obtain a Co-Mn mixed salt solution; adding a complexing agent into the Co-Mn mixed salt solution to form a stable sol system; heating the sol system at constant temperature to obtain wet gel; drying the wet gel to obtain a porous dry gel precursor; calcining the porous xerogel precursor, and then cooling and grinding to obtain the composite catalyst for the peracetic acid activation system. The composite structure in the catalyst greatly improves the rate of generating hydroxyl radicals and organic oxygen radicals by decomposing peracetic acid by promoting electron transfer circulation of a metal active center, shows good structural stability and recyclability, and is especially suitable for degradation of an organic pollutant sulfamethoxazole in a water body.

The invention relates to the technical field of photocatalytic processes, in particular to a catalyst for preparing methanol through photocatalytic reduction of CO2 as well as a preparation method and application of the catalyst. The catalyst comprises a composite carrier and active sites dispersed on the surface or in pores of the composite carrier, the composite carrier is of a heterojunction composite structure formed by a hollow TiO2 sphere and MCN, the hollow TiO2 sphere comprises a shell layer and a spherical cavity structure located in the shell layer, the shell layer is formed by TiO2 nanoparticles, and the MCN has a mesoporous pore structure; a II-type or Z-type heterojunction interface is formed between the hollow TiO2 spheres and the MCN through physical contact and chemical action; the active sites comprise copper nano species, sulfur vacancy defects and amino groups; the copper nano species are copper nano particles or clusters, and the valence state of copper is 0 and / or + 1 valence amino is grafted on the surface of the composite carrier through an organic long chain. The catalyst provided by the invention can greatly improve the yield and selectivity of methanol prepared by photocatalytic reduction of carbon dioxide.

The application discloses a bifunctional HMGR mutant, which is obtained by replacing aspartic acid at the 154th amino acid of the amino acid sequence of natural HMGR with other amino acids. The application also discloses a nucleotide sequence and an amino acid sequence. The application further discloses a preparation method and application of the bifunctional HMGR mutant. The HMGR mutant of the application has high activity to both NADP(H) and NAD(H) substrates, and has significantly improved catalytic activity in a certain pH range.

The application relates to the technical field of organic wastewater treatment, in particular to a preparation method and application of an ozone catalyst, and the preparation method and application of the ozone catalyst, the method comprising the following steps: (1) ball milling, (2) melting and (3) staged cooling; the catalyst can promote the reaction between ozone molecules and refractory organic matters, effectively reduces the refractory COD in water, improves the COD removal rate, improves the ozone utilization rate, and achieves the purpose of improving the sewage treatment efficiency.

The invention discloses a bimetallic oxide supported catalyst as well as a preparation method and application thereof. The bimetallic oxide supported catalyst comprises a bimetallic oxide carrier and a metal active component supported on the surface of the bimetallic oxide carrier; the bimetallic oxide carrier contains a divalent metal element oxide and a trivalent metal element oxide; the divalent metal element oxide is selected from at least one of oxides of Mg, Ca, Sr, Zn and Mn; the trivalent metal element oxide is selected from at least one of oxides of Al, In, Fe, Cr and Ce; the metal active component is selected from at least one of Pd, Pt, Ru, Ni and Co; in the bimetallic oxide supported catalyst, the mass of the metal active component is 0.1-20 wt% of the mass of the metal oxide carrier.

The application relates to a preparation and application of a molybdenum and indium co-modified cobalt-based catalyst for carbon dioxide hydrogenation synthesis of low-carbon alcohol, belonging to the field of catalysis. Co is used as an active component, In and Mo components are introduced, an alkali metal K additive is introduced, an In and Mo co-modified Co-based oxide precursor is created by adopting a sol-gel method, the precursor is reduced by hydrogen, and is further activated by CO2+H2, so that the In and Mo co-modified Co2C catalyst is obtained; the catalyst is used in a reaction of carbon dioxide hydrogenation for preparing low-carbon alcohol, under the condition that the reaction temperature is 340 DEG C and the reaction pressure is 3 MPa, the carbon dioxide conversion rate is more than 35%, and the low-carbon alcohol selectivity is close to 20%.

The application discloses an electrode material based on MOF@COF / BC and application thereof in wastewater treatment and belongs to the technical field of wastewater treatment. The electrode material is prepared by the following method: NH2-MIL101(Fe), melamine and phthalocyanine molybdenum are dissolved in dimethyl sulfoxide, reaction is carried out at 160-200 DEG C for 10-14 h, the precipitate is collected after reaction, and washing, drying are carried out to prepare NH2-MIL101(Fe)@Mel-MoPc; the biochar and NH2-MIL101(Fe)@Mel-MoPc are mixed in deionized water, ultrasonic treatment is carried out for 8-12 min, stirring is carried out for 10-14 h, then the precipitate is collected by centrifugation, and washing, drying are carried out to prepare the electrode material. The application develops and designs a novel electrode material, which is used for electrocatalytic activation of peroxymonosulfate to degrade OFX wastewater, and the degradation efficiency of the OFX wastewater is greatly improved.

The invention relates to the technical field of catalysts, and discloses a catalyst and a preparation method thereof, and a method for preparing 4-methyl-1-pentene through propylene dimerization, the catalyst comprises a carrier, and an active metal component and an auxiliary metal component loaded on the carrier; wherein the carrier comprises potassium carbonate and a binder, the active metal component is selected from sodium and / or potassium, and the auxiliary metal component is selected from at least one of precious metals; wherein on the basis of the mass of the carrier, the content of the active metal component is 1-20wt% and the content of the auxiliary metal component is 0.1-10wt% in terms of metal elements. The catalyst has high catalytic activity and stability in propylene dimerization reaction.

The present invention relates to a copper oxide powder having a specific surface area of at least 25.0 m 2 / g to 70.0 m 2 / g, a crystallite size of not more than 150.0 Angstrom (A), and a chlorine content of less than 200 ppm, and a process for the production of the copper oxide powder.

The application provides a method for improving the yield of oxygen-containing compounds in low-rank coal-derived soluble matters, and belongs to the technical field of low-rank coal pretreatment, and comprises the following steps: first, performing ozone oxidation pretreatment on low-rank coal to obtain modified low-rank coal; using cobalt acetate, copper acetate and iron acetylacetonate as a cobalt source, a copper source and an iron source respectively, using hydrazine hydrate as a strong reducing agent, and using a one-pot hydrothermal method to obtain magnetic Co-CuFe2O4 nanospheres; and using the prepared Co-CuFe2O4 nanosphere catalyst to perform catalytic ethanolysis reaction on the low-rank coal subjected to ozone oxidation pretreatment. In the application, appropriate ozone oxidation pretreatment can effectively improve the activity of the low-rank coal, and when the magnetic Co-CuFe2O4 nanospheres are applied to catalytic ethanolysis reaction of the low-rank coal subjected to ozone oxidation pretreatment and catalytic ethanolysis reaction of low-rank coal-related model compounds, the magnetic Co-CuFe2O4 nanospheres all exhibit excellent catalytic activity, higher-yield soluble components can be obtained, the yield of oxygen-containing compounds in the derived soluble matters is improved, and efficient and high-value utilization of the low-rank coal is realized.

The application relates to a method for producing jet fuel from oil and fat raw materials, wherein the oil and fat raw materials are reacted with a hydrotreating catalyst in a hydrotreating reaction zone, the obtained liquid hydrocarbons are introduced into a first hydroisomerization reaction zone, an optional second hydroisomerization reaction zone is arranged, the obtained diesel oil fraction is recycled into the first hydroisomerization reaction zone or introduced into the second hydroisomerization reaction zone for reaction, and the reaction effluent is separated to obtain jet fuel. The application can produce high-quality biological jet fuel at a high yield.

The invention provides a metal monatomic loaded lamellar stacked carbon nitride hollow cubic material as well as a preparation method and application thereof, and ACT-Fe / Na-C3N4 (0.04) with a three-dimensional hollow cubic morphology and uniformly dispersed in-plane / interlayer double Fe monatomic sites is successfully prepared by utilizing a morphology amorphous-to-crystalline transition (ACT) strategy. And crystal form regulation and fine design of metal atom sites are integrated. The built in-plane Fe-N4 and interlayer Fe-N5 coordination structure significantly improves the electron transport efficiency of the material, enhances the adsorption and activation ability to O2 molecules, realizes efficient generation of. O2 <->, and provides controllable reaction conditions for selective conversion of biomass, so that the HMF conversion rate reaches 98.8%, and the HMFCA selectivity reaches 83.7%. In addition, the ACT strategy is generally suitable for the assembly of a variety of transition metals (Mn, Fe, Co, Cu or Cd) at the same time.

The application belongs to the technical field of proton exchange membrane fuel cell, and relates to a hydrophobicity-adjustable alloy nanotube array electrode for fuel cell and preparation and application thereof. Specifically, the application comprises preparation of metal nanotube array, alloying and hydrophobization of the metal nanotube array, and assembly of the membrane electrode. First, a metal nanotube array is constructed on a substrate surface through a two-step hydrothermal method; then, a hydrophobic substance is introduced into the metal nanotube array by means of immersion or ultrasonic spraying; then, pyrolysis is performed to realize alloying and hydrophobization of the nanotube array; finally, the nanotube array is transferred to a proton membrane, and the membrane electrode is cleaned. The membrane electrode can be applied to a proton exchange membrane fuel cell. The hydrophobicity-adjustable nanotube array electrode prepared by the application has the advantages of high catalyst activity and stability, low platinum loading, good water management, and easy scaling-up.

The present application belongs to the technical field of biomass catalytic conversion, and particularly relates to a method for preparing polyols by hydrogenation of furfural and its derivatives. The method comprises the following steps: taking furfural and its derivatives as raw materials, hydrogen as hydrogen source, and simultaneously adding a catalyst La2CuO4 / Cu to perform ring-opening reaction to obtain polyols. The catalyst La2CuO4 / Cu has excellent catalytic activity in the reaction of hydrogenation conversion of furfural and its derivatives into polyols, has high activity and selectivity for the rupture of C-O bonds of reactants, improves the yield of polyols, and has mild reaction conditions, realizes recovery and long-time use without deactivation of the catalyst, and reduces the utilization cost.

The application discloses a composite catalyst for chemical flow casting preparation of a polyimide film and a method for preparing the polyimide film. After a polyamide acid composition is flow cast on a support to form a gel film, the polyimide film is prepared through high-temperature curing. The polyamide acid composition is uniformly mixed at normal temperature from a polyamide acid solution, a polar aprotic solvent, an imidization composite catalyst, a thermal latent catalytic type blocking agent and a dehydrating agent. The imidization composite catalyst is compounded from two types of imidization catalysts with high activity and low activity respectively. The application develops a normal-temperature (16 DEG C to 35 DEG C) chemical flow casting preparation method of a PI film by adopting the imidization catalysts with high catalytic activity and low activity to prepare the composite catalyst. Compared with a traditional low-temperature chemical flow casting method, the manufacturing energy consumption and manufacturing cost are greatly reduced.

The invention discloses a high-temperature-resistant high-activity metallocene catalyst and application thereof, and belongs to the technical field of olefin polymerization catalysts. The catalyst provided by the invention is formed by taking a fused ring structure with a rigid framework as a ligand framework and coordinating with transition metal titanium, zirconium or hafnium, so that the catalyst has excellent thermal stability and high catalytic activity, and is suitable for copolymerization reaction of ethylene and alpha-olefin. In the high-temperature polymerization reaction, the catalyst provided by the invention realizes efficient copolymerization of ethylene and alpha-olefin, and the obtained copolymer not only has higher molecular weight, but also has higher comonomer insertion amount, so that the structure and performance of the product are effectively regulated and controlled.

The application belongs to the field of medical materials, and particularly relates to a metal core enhanced double-barrier piezoelectric nano system and a preparation method and application thereof. The preparation method comprises the following steps: first, a core-shell structure of'metal@mesoporous titanium dioxide@mesoporous barium titanate' is prepared through a step-by-step reaction, and then the target nanoparticles are obtained through lipid wrapping. The system innovatively constructs a double-barrier structure, can self-trigger active oxygen under a physiological pressure of 4 mmHg, realizes endogenous pressure self-driven treatment of malignant ascites, has the advantages of low pressure, high catalytic efficiency, long-term structural stability and good biocompatibility, solves the problems that existing treatment methods are highly invasive and depend on exogenous stimulation, and provides a new safe and efficient technical scheme for the treatment of malignant ascites.

The application discloses a precious metal embedded porous carbon coated honeycomb ceramic monolithic catalyst and application thereof. The liquid phenolic resin polymer containing chloroplatinic acid is uniformly coated on the surface of the cordierite honeycomb ceramic through impregnation treatment; in an oxygen-nitrogen mixed atmosphere, one-stage solidification makes the liquid phenolic resin polymer containing chloroplatinic acid coated on the surface of the cordierite honeycomb ceramic completely solidified; two-stage calcination makes oxygen react with chloroplatinic acid, so that the chloroplatinic acid is decomposed, and the negative influence of chloride ions on the catalyst is eliminated; in an inert gas argon atmosphere, carbonization makes the phenolic resin polymer carbonize under high-temperature conditions to form porous carbon, and meanwhile, platinum ions are reduced to platinum single elements and embedded by the porous carbon, so that the precious metal (platinum, iridium) embedded porous carbon coated honeycomb ceramic monolithic catalyst is finally prepared.

This invention discloses a method for preparing FeZn-LDH nanosheets and their application in glucose colorimetric detection, belonging to the field of nanoenzyme technology. The preparation method involves introducing arginine and L-histidine into an Fe / Zn metal salt system and combining this with microwave-induced heating to prepare FeZn-LDH nanosheets. The prepared FeZn-LDH nanosheets effectively prevent LDH aggregation, resulting in a thinner, two-dimensional FeZn-LDH nanosheet structure with a larger specific surface area, thereby improving the peroxidase-like catalytic activity and glucose colorimetric detection performance of the material.

The application belongs to the field of biopharmacy and bioconversion, and particularly relates to a lipase mutant and application thereof. The lipase CALB mutant of the application is obtained by adopting single-point mutation or combined mutation on positions 40, 134, 154, 189, 278 and 281 of the amino acid sequence shown in SEQ ID NO. 1. The mutant greatly improves the stereoselectivity in catalyzing the production of (S)-3-cyclohexene-1-methyl formate from racemic 3-cyclohexene-1-methyl formate. Compared with the traditional chemical method for preparing (S)-3-cyclohexene-1-methyl formate, the lipase CALB mutant provided by the application has high stereoselectivity, mild reaction conditions, is friendly to the environment, has reduced requirements on equipment, greatly reduces the production cost, and shows a wide application prospect in industrial application.

The application discloses a kind of delta-MnO2-GO catalyst and its preparation method and application in room temperature formaldehyde degradation, it is related to inorganic catalyst technical field.The preparation method of delta-MnO2-GO catalyst of the application can significantly limit the growth of manganese dioxide nanosheet by doping with low amount of GO, to manufacture abundant mass transfer transmission channel, delta-MnO2-GO catalyst presents unique two-dimensional crown structure, two-dimensional coral-like hierarchical pore structure delta-MnO2 nanorod is uniformly dispersed on the GO of plane structure, greatly promote the exposure of catalytic site and the mass transfer of reactant, produce a large number of surface active oxygen ROS and hydroxyl radical-OH, greatly maintain the excellent catalytic activity and stability to HCHO degradation, stably realize nearly 100% HCHO elimination at room temperature.

The application discloses a MgO-based catalyst synthesis method and application thereof, relates to the technical field of catalyst preparation, and comprises the following steps: dissolving magnesium salt, lanthanum salt, cerium salt, calcium salt and nickel salt in deionized water, stirring uniformly to obtain a metal salt solution; adding citric acid into the metal salt solution and stirring intensively until uniform to form a mixed gel; pouring the mixed gel on a medium-speed qualitative filter paper, transferring and drying to obtain a dry gel; roasting the dry gel with the filter paper, grinding the roasted dry gel with a mortar to obtain a grinding powder; and transferring the grinding powder to a muffle furnace for calcination to obtain a uniform composite metal oxide catalyst; the MgO-based catalyst is prepared by combining the dry gel method with the combustion decomposition method, the preparation process is simple, the conditions are easy to control, the preparation process is easy to repeat, the product pollution risk caused by the introduction of sodium hydroxide precipitator is eliminated, the preparation cost and process difficulty are reduced, and the method is suitable for large-scale production. + ​

The invention provides an MOF-on-MOF composite material, an aptamer probe as well as a preparation method and application of the aptamer probe. The MOF-on-MOF composite material comprises an HKUST-1 material, the surface of the HKUST-1 material is coated with a Cu-BDC nanosheet; the synthesized HKUST-1 (at) Cu-BDC / Apt aptamer probe can specifically recognize AFB1, the aptamer probe can directly capture the AFB1 and adsorb the AFB1 to active sites on the surface of a material to reduce the nano-enzyme activity of the AFB1, so that quantitative colorimetric detection of the AFB1 is realized, and the aptamer probe has low detection limit, wide detection range, good selectivity and anti-interference performance on the AFB1 and can be used for detecting the AFB1. The AFB1 in a food sample can be rapidly, sensitively and selectively detected. In addition, the composite material has an adsorption effect and high catalytic activity on fungaltoxin, and AFB1 can be efficiently removed through the adsorption effect and the catalytic action.

This application provides a vanadium-based catalyst and its application. The catalyst includes a main catalyst, a co-catalyst, and a porous support. The main catalyst and the co-catalyst are dispersed on the porous support. The main catalyst includes vanadium and optionally molybdenum, and the co-catalyst includes fullerene. Using this vanadium-based catalyst to catalyze the methylation reaction of mixed tocopherols to produce D-α-tocopherol can effectively improve the yield and content of D-α-tocopherol.

The invention provides a metallocene catalyst and a preparation method and application thereof. The method comprises the following steps: providing a first silicate aqueous solution with the pH value of 9-10 as a base solution; mixing the second silicate aqueous solution, inorganic acid and the base solution, and aging at 70-80 DEG C to obtain a first mixed solution; mixing and reacting the first mixed solution, an alkaline substance and organic alcohol to obtain a second mixed solution; mixing and reacting the second mixed solution, an alkaline substance and organic alcohol to obtain a hydrogel system; mixing the hydrogel system with inorganic acid to obtain acidified gel; performing first post-treatment to obtain a silica gel carrier; carrying out thermal activation on the silica gel carrier, and mixing and reacting with an aluminum alkyl solution to obtain MAO modified silica gel; and mixing the MAO modified silica gel with a metallocene compound, reacting, and carrying out second post-treatment to obtain the metallocene catalyst, wherein the alkaline substance comprises one or a combination of more than two of ammonia water, ammonium carbonate and ammonium bicarbonate. The metallocene catalyst has good catalytic activity.

The invention discloses a rare earth tailing-based aerogel catalyst for refractory coal and a preparation method thereof, and the preparation method comprises the following steps: a, pretreating rare earth tailings rich in cerium oxide to obtain raw material powder; b, carrying out modification treatment on the raw material powder obtained in the step a to obtain modified powder; and c, preparing rare earth tailing-based aerogel from the modified powder obtained in the step b, and grinding to obtain the catalyst. The rare earth tailing-based aerogel catalyst prepared by the invention has a relatively high specific surface area and a rich pore structure, obviously improves the combustion efficiency of fire coal, can be suitable for fire-retardant solid fuel, realizes wide-load stable combustion of fire-retardant coal powder, expands the coal type adaptability of a unit, reduces the use amount of long flame coal, and reduces the production cost. The coking problem is effectively solved.

The invention belongs to the technical field of photocatalytic hydrogen evolution, and discloses preparation and application of a platinum monatomic modified zinc cadmium sulfide catalyst. Aiming at the urgent demand of clean energy under energy crisis and the problems of insufficient efficiency, complex preparation, high cost and the like of the existing photocatalytic hydrogen evolution material, the invention aims to provide a catalyst which is simple and convenient in process, controllable in cost and excellent in hydrogen evolution performance. According to the preparation method, zinc acetate, cadmium chloride, thiourea, polyvinylpyrrolidone, potassium tetrachloroplatinate and a hydrazine hydrate solution are taken as raw materials, and precise modification and stable loading of platinum single atoms on the surface of zinc cadmium sulfide are realized through combination of a hydrothermal synthesis method and a photodeposition technology. The catalyst shows excellent catalytic activity and long-term stability in the field of photocatalytic hydrogen evolution, the hydrogen evolution efficiency can be remarkably improved, an efficient solution is provided for clean energy development, and the application value is wide.

The invention discloses a beta-glucosidase mutant, an immobilized enzyme of the beta-glucosidase mutant and application of the beta-glucosidase mutant in efficient synthesis of kinsenoside, and belongs to the field of enzyme engineering and natural product biosynthesis. According to the mutant, one or more mutations of W177Y, W179F, Q242A, F245G, R298S and R313T are introduced at key sites of an amino acid sequence of wild type beta-glucosidase, so that the yield of catalytic synthesis of kinsenoside is remarkably improved. Furthermore, a metal organic framework material UiO-66-NH2 is adopted as an immobilization carrier, enzyme immobilization is achieved in a physical adsorption mode, and the obtained immobilized enzyme is excellent in reusability. Under the same reaction conditions, the immobilized mutant enzyme is used for catalyzing synthesis of kinsenoside, and the yield of the immobilized mutant enzyme is 3 times that of a wild enzyme. The invention provides an efficient, green and sustainable kinsenoside biocatalytic synthesis scheme, and the kinsenoside biocatalytic synthesis method has a good industrial application prospect.

The application provides a preparation method of a double-metal MOF material functionalized transistor sensor for BPA detection, and the material uses ZIF-8 as a carbon source, and a carbon material (Ce@ZIF8 / C) with rich mesoporous structures and good dispersed metal active sites embedded with Ce and Zn double metals is successfully prepared by using a direct pyrolysis method. The Ce@ZIF8 / C material prepared by the application can be applied to the functionalization of a gate electrode of an SGGT sensor, and an electrochemical sensor for real-time monitoring of an organic pollutant BPA in water can be successfully constructed. The electrochemical sensor constructed by the material synthesized by the application has good detection performance on BPA.