222 results about "Catalytic effect" patented technology

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 a preparation method of a bifunctional heterojunction catalyst for AEM electrolyzed water. The method comprises the following steps: step 1, mixing multi-walled carbon nanotubes, deionized water, absolute ethyl alcohol and inorganic acid; step 2, putting the mixed solution in the step 1 into an ultrasonic machine to form a porous structure and more active adsorption sites; step 3, carrying out freeze drying treatment on the mixed solution treated in the step 2; step 4, mixing the dried multi-walled carbon nanotubes with acetylacetone salt, and uniformly grinding the mixed powder; and step 5, putting the powder obtained in the step 4 into a tubular furnace, and carrying out heat treatment in the atmosphere of H2 / Ar to obtain the PtFeCoNiMoZr / ZrO heterojunction catalyst. The catalyst has a remarkable catalytic effect on HER and OER reactions, and meanwhile, stable electrolysis which stably runs for 200 hours in an AEM electrolytic cell under the current density of 1200 mA / cm < 2 > is successfully realized.

The invention relates to a lignin-derived carbon aerogel loaded metal nano enzyme and a synthesis method and application thereof, the synthesis method comprises the following steps: adding sodium lignin sulfonate, CoCl2. 6H2O and NiCl2. 6H2O into deionized water, and carrying out ultrasonic dispersion to obtain a lignin-metal solution; uniformly mixing and stirring the lignin-metal-PVA composite precursor solution with a polyvinyl alcohol aqueous solution to obtain a lignin-metal-PVA composite precursor solution; carrying out at least three times of freezing-unfreezing circulation treatment on the lignin-metal-PVA composite hydrogel to obtain lignin-metal-PVA composite hydrogel; carrying out freeze drying treatment to remove moisture, so as to obtain a lignin-metal-PVA composite aerogel precursor; and carrying out pyrolysis treatment in a nitrogen environment, and naturally cooling to room temperature. The lignin-derived carbon aerogel loaded Co-Ni bimetallic nano-enzyme prepared by the invention shows excellent catalytic activity, product selectivity and cycle stability in photocatalytic CO2 reduction reaction of high and low concentration CO2 due to bimetallic synergistic catalytic effect, high specific surface area and stable three-dimensional skeleton.

The invention belongs to the technical field of synthesis and antibiosis of nano-enzyme catalysis systems, and discloses an enzyme catalysis system with a function of targeted inhibition of growth of streptococcus mutans as well as preparation and application of the enzyme catalysis system. The enzyme catalysis system with the targeted inhibition function on the growth of the streptococcus mutans is formed by loading AuNPs and PCN-22 (Fe) on a CMD molecular chain through in-situ growth, and the mass ratio of the AuNPs to the PCN-22 (Fe) to the CMD is (0.22%-0.33%) to (12.34%-21.79%) to (77.88%-87.44%). The cascade catalytic effect of the nano-enzyme is adjusted by regulating and controlling the carboxymethyl substitution degree of CMD, so that glucose in a decayed tooth pathological environment is efficiently catalyzed in one step to generate ROS, and damage to probiotics is reduced while the inhibition efficiency of pathogenic bacteria is improved.

The invention discloses cysteine mediated Hf / Cu bimetal synergistic self-assembled nano-particles as well as a preparation method and application of the cysteine mediated Hf / Cu bimetal synergistic self-assembled nano-particles. According to the method, cysteine is used as a multifunctional ligand, carboxyl and sulfydryl of cysteine are in bridge connection with metal through coordination, ligand chelation and assembly guiding effects are synchronously exerted, bimetallic ions are induced to be cooperatively self-assembled in an alkaline system (pH is 9-10), and metal cysteine self-assembled nanoparticles with uniform structures are formed through in-situ nucleation and multistage aggregation. According to the method, the ligand function and the bimetallic synergistic effect are accurately matched, the synthesis process is mild (room temperature), the operation is simple and convenient, and the product is excellent in dispersity and stability. Meanwhile, a close coordination structure constructed by cysteine provides a key channel for energy / electron transfer from sensitizing metal to Cu under X-ray irradiation, and lays a structural foundation for subsequent catalytic effect enhancement.

The invention discloses a method for preparing rare saponin by utilizing panax japonicus endogenous enzyme, and relates to the technical field of extraction, the panax japonicus plant material or crude extract thereof is directly taken as a starting point, the enzyme system is simple and convenient to obtain (fresh medicinal material low-temperature homogenate extraction or direct use of freeze-dried powder), the reaction system is simple, and the operation is easy. According to the preparation process provided by the invention, the catalytic action of endogenous enzyme is fully utilized, so that the introduction of exogenous substances (acid-base, protein and the like) in the extract is completely avoided; the method disclosed by the invention is high in catalytic efficiency, can quickly realize complete conversion of saponin (within 10min) under specific conditions, and has extremely high industrial application.

The application discloses a preparation method of a mesoporous silicon-based composite material with phosphotungstic acid and titanium oxide simultaneously supported, and belongs to the technical field of catalytic material preparation. The method aims to solve the problems of easy aggregation of active components, easy damage of channel order and complex preparation process in the prior art. The method is characterized by the following steps: through a one-step hydrothermal synthesis strategy, a triblock copolymer is used as a structure directing agent, an alcohol solution of a titanium source precursor, a silicon source precursor and a Keggin type phosphotungstic acid is simultaneously added in an acid system, and then the mesoporous silicon-based composite material is prepared through hydrothermal crystallization, washing, drying and calcination. The method is simple in process and controllable in operation, and the obtained material has the following advantages: two-dimensional hexagonal ordered mesoporous structure, large specific surface area, high dispersion of titanium and phosphotungstic acid, intact Keggin structure, good double-acid-site synergistic catalytic effect, and suitability for acid catalytic reactions, especially in the field of biomass conversion.

The application discloses a triphenylmethane polyether dye and a preparation method thereof, and the preparation method comprises the following steps: (1) adding an organic catalyst and an oxidant into a triphenylmethane polyether dye leucoaqueous solution in the interval of 40-60 DEG C, adding an acid-binding agent to maintain a proper pH, and completing oxidation; the organic catalyst is a ferrocene-rotene iron compound; (2) adjusting the pH with an acid-binding agent aqueous solution, removing the organic catalyst by hot filtration, removing water through vacuum distillation of the filtrate, and performing pressure filtration to obtain the triphenylmethane polyether dye. The improved rotene iron catalyst is used in the application, the catalytic effect is obviously improved, the reaction temperature and activation energy are reduced, the defects of excessive hydrogen peroxide oxidation are overcome, and the obtained product meets the EN71-3 standard.

The present application relates to furan preparation technical field, specifically to a kind of furfural decarbonylation catalyst, preparation method and utilize the catalyst preparation furan process.The catalyst includes carrier and active component supported on it, with the mass of the carrier, Pt 0.2%‑0.6%, Co 4%‑8%, Al2O3 74%‑85%, ZrO2 11%‑16%, CeO2 4%‑13%.The present application adopts structural aid ZrO2 and CeO2 to modify Al2O3 carrier, obtains acid moderate composite oxide carrier, can avoid the influence of furfural polymerization and the activity and stability of catalyst;Using Co as auxiliary active component, under the premise of reducing the dosage of main active component Pt, ensure catalytic effect, not only reduce the cost of catalyst, more importantly, it can improve the conversion rate of furfural and furan selectivity in furfural decarbonylation reaction, ensure high furan yield.

The invention discloses a chiral 1, 4-diazabicyclo [3.1. 1] heptane derivative as well as a synthesis method and application of the chiral 1, 4-diazabicyclo [3.1. 1] heptane derivative. According to the invention, a 1-azabicyclo [1.1. 0] butane derivative is taken as a raw material, under the catalytic action of a chiral iridium complex, the 1-azabicyclo [1.1. 1] butane derivative and an N-allyl carbonate derivative are subjected to [3 + 2] cycloaddition reaction, a series of chiral 1, 4-diazabicyclo [3.1. 1] heptane skeletons with diversified structures are constructed with high stereoselectivity, and the obtained product has the potential of further derivatization. The method has the advantages of easily available raw materials, mild reaction conditions, simplicity and convenience in operation, good functional group compatibility and the like.

The invention discloses an Ag monatomic catalyst, a preparation method thereof and application of the Ag monatomic catalyst in preparation of amino acid, and belongs to the technical field of amino acid preparation. The Ag monatomic catalyst comprises a carrier and an active component, wherein the active component is dispersed on the surface of the carrier in a monatomic form; the carrier is a metal oxide, and the metal oxide comprises one of CeO2, Fe2O3, TiO2, ZnO, Nb2O5 and ZrO2; the active component is Ag, and the loading capacity of the active component is 0.05-0.5 wt%; the Ag monatomic catalyst is used for preparing amino acid, and amino alcohol and O2 are subjected to oxidation reaction under the catalytic action of the Ag monatomic catalyst to obtain the amino acid. The catalyst provided by the invention has a high catalytic effect on amino acid preparation by oxidation of amino alcohol, and is mild in reaction condition and high in amino acid selectivity; meanwhile, the catalyst has high stability in the amino acid preparation process, and the catalytic activity can be kept in the long-time production process.

A ZIF-derived zinc-cadmium sulfide photocatalyst, its preparation method, and its application are disclosed. The catalyst, by molar fraction, comprises: 35-50% 2-methylimidazole; 0-7.7% divalent cadmium ion compound; 0-7.7% divalent zinc ion compound; 7-10% thioacetamide; and 35-50% amines. The preparation method involves: preparing a 2-methylimidazole solution and a cadmium-zinc mixed solution separately; then preparing a ZIF precursor solution with cadmium and zinc as the central metals; adding thioacetamide to the precursor solution; transferring the solution to a polytetrafluoroethylene liner and hydrothermally treating it; finally collecting the hydrothermally treated solution, centrifuging, washing, drying, and grinding to obtain the ZIF-derived zinc-cadmium sulfide photocatalyst. The catalyst prepared by this invention has a large specific surface area and exhibits significant catalytic effects in photocatalytic water splitting for hydrogen production. Furthermore, the catalyst has a stable structure and can be recycled for a long period without a significant decrease in the hydrogen production rate.

The invention relates to an oil-containing sludge biochar catalyst, a preparation method thereof and a method for removing organic pollutants in sewage, the method comprises the following steps: S1, heating a mixture containing saccharides, amino compound raw materials, inorganic alkali and oil-containing sludge for Maillard reaction to obtain a precursor containing a nitrogen-containing heterocyclic compound; wherein the amino compound raw material contains amino acid and / or protein; and S2, in an inert atmosphere, carrying out pyrolysis on the precursor containing the nitrogen heterocyclic compound. The oily sludge biochar catalyst prepared by the method disclosed by the invention has a better catalytic effect on activating persulfate to degrade organic pollutants in a water body.

The invention relates to the field of catalysts, in particular to a multi-scale microporous catalyst and a preparation method thereof.Firstly, diffusion and mass transfer of reactants and products are greatly accelerated through a through multi-stage pore network of the catalyst, the exposure degree of active sites is remarkably increased, and therefore the catalytic efficiency is improved; secondly, according to the system, the pore structure and the material composition can be optimized and combined according to the characteristics of different catalytic reactions, such as reactant sizes, reaction media and conditions, so that the system can be widely adapted to various reaction types such as a gas state and a liquid state, and covers most of catalytic scenes; furthermore, various preparation methods can be flexibly combined, especially the 3D printing technology is applied, so that design customization of multi-scale pores and the appearance of the catalyst is realized, and the preparation difficulty of a complex structure is greatly reduced; and finally, reasonable framework material selection and multistage pore design synergistically enhance the catalytic effect and inactivation resistance of the catalyst, so that the service life of the catalyst is prolonged compared with that of a traditional catalyst.

The invention discloses a preparation method of an optically pure mepivacaine hydrochloride intermediate. According to the method, N-(2, 6-dimethylphenyl) pyridine carboxamide is used as a starting material, hydrogenation reduction is carried out in the presence of a ligand and a catalyst to obtain the mepivacaine hydrochloride intermediate ((S)-N-(2, 6-dimethylphenyl) piperidine-2-carboxamide), the ee value of the obtained mepivacaine hydrochloride intermediate can reach 93%, the yield can reach 95%, post-treatment is simple, and the method is suitable for industrial production. The method is very suitable for large-scale workshop production. The ligand used in the invention is cheap and easily available, and can be refined and recovered through column chromatography, and the catalytic effect of the recovered ligand is consistent with that of a newly purchased ligand.

The application provides a continuous palladium-carbon hydrogenation reaction method, which is carried out according to the following steps: step one, mixing carbon catalyst with a solvent, and then injecting into the inside of a reactor; step two, connecting and starting a circulating pump to make the inside catalyst partially flow in a circulating mode; step three, injecting p-nitrotoluene and hydrogen, and carrying out heat exchange treatment on the whole reactor through a heat exchanger to keep the temperature stable during the reaction; and step four, discharging the reaction liquid and carrying out filtration treatment. The continuous palladium-carbon hydrogenation reaction method and equipment optimize the catalytic effect of the catalyst, improve the filtration efficiency, ensure that the raw material liquid and hydrogen enter the reactor, make the catalyst freely flow in the whole reaction area without being discharged from the reactor, continuously remove the product from the reactor, keep the temperature stable during the whole reaction process through the heat exchanger, and automatically stir the inside through the hydrogen injection.

This invention discloses a paint remover for steel-aluminum composite materials, belonging to the field of metal material surface treatment technology. It comprises the following components in weight percentages: 5%-8% alkaline substance; 5%-10% lipase component; 10%-16% solvent; 5%-10% surfactant; 6%-13% co-solvent; 5%-8% corrosion inhibitor; and water as the balance. The paint remover is prepared from alkaline substance, lipase component, solvent, surfactant, co-solvent, corrosion inhibitor, and water. It is used for removing paint from steel-aluminum composite materials. On one hand, the alkaline substance saponifies some groups in the paint, dissolving them in the solvent and water. On the other hand, heating and steaming the paint film reduces its strength and adhesion to the metal. Then, utilizing the wetting, penetration, and affinity effects of the surfactant, the catalytic effect of the lipase component, and the protective effect of the corrosion inhibitor on the steel-aluminum substrate, the goal of removing paint quickly without corroding the substrate is achieved.

The application provides a novel ozone catalytic oxidation tower for wastewater treatment, and relates to the technical field of wastewater treatment, and comprises an outer shell, a liquid adding pipe fixedly connected to one side of the outer surface of the outer shell, an air adding pipe fixedly connected to one side of the outer surface of the outer shell, air adding equipment fixedly connected to one end of the outer surface of the air adding pipe, a first motor fixedly installed at the top of the outer surface of the outer shell, a second motor fixedly installed at the top of the outer surface of the outer shell, and a storage bin fixedly installed in the inner part of the outer shell. The cooperation of the storage bin, the rotating shaft, the connecting cylinder, the rotating stirring device and the intermittent feeding plate realizes stirring before catalyst addition and periodic addition. The cooperation of the heating multilayer pipe and the storage bin avoids catalyst dampening, and the already dampened catalyst can be heated to remove dampness, recover the decomposition function, avoid catalyst caking, and ensure the catalytic effect of the catalyst.

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 invention belongs to the field of catalyst technology, and relates to a flower-like multifunctional CuO@MnO2 composite material, its preparation method, and its application. The composite material constructs a flower-like core-shell structure with CuO as the core and thin-film MnO2 as the shell. The preparation method is as follows: rod-shaped copper hydroxide is added to deionized water and ultrasonically mixed to obtain a copper hydroxide suspension; potassium permanganate is dissolved in the copper hydroxide suspension and ultrasonically mixed to obtain a mixed solution B; mixed solution B is subjected to a hydrothermal reaction, and after the reaction is completed, it is cooled, washed, and dried to obtain the flower-like multifunctional CuO@MnO2 composite material. This method not only maximizes the interfacial contact area between the two phases and promotes interfacial charge transfer to achieve a synergistic catalytic effect, but also provides a MnO2 shell with good stability, forming a physical and chemical barrier for the CuO core and effectively inhibiting the excessive leaching of copper ions. Furthermore, the prepared CuO@MnO2 exhibits good catalytic performance, stability, and reproducibility.

The invention discloses a catalyst combination method for simultaneously removing CO and NOx in flue gas, which is characterized in that two reaction systems are arranged in a flue gas purification device, the flue gas enters the flue gas purification device, ammonia spraying operation is carried out, oxidation reaction is carried out on the upper layer of the flue gas purification device, and CO in the flue gas is oxidized into CO2 and part of NO is oxidized into NO2 under the catalytic action of an oxidation catalyst Co1-xNix / Al2O3; according to the method, CO and NOx in the flue gas are removed at the same time, NH3-SCR reaction is carried out on the lower layer of the flue gas purification device, and under the catalytic action of a NOx selective reduction catalyst, blown ammonia gas and NOx in the flue gas are converted into N2 and H2O, so that CO and NOx in the flue gas are removed at the same time. The flue gas purification device is utilized to realize efficient and synergistic removal of CO and NOx, and has the characteristics of high efficiency, simple catalyst preparation, convenience in engineering application and the like.

The application relates to the technical field of catalysts, and discloses a composite organic acid catalyst for acetate production, a preparation method and application thereof.The composite organic acid catalyst for acetate production comprises silica-supported organic acid; the silica-supported organic acid is silica-supported methyl sulfonic acid and silica-supported alkane disulfonic acid; and the mass ratio of the silica-supported methyl sulfonic acid and the silica-supported alkane disulfonic acid is 1.5:0.4-1.4.Through the technical scheme, the problem that the yield of acetate is not high due to the insufficient catalytic effect of the solid acid catalyst in the prior art is solved.

This invention relates to the field of semiconductor process chamber cleaning technology, specifically to a semiconductor process chamber cleaning gas composition based on HFO-1447fz, a remote plasma cleaning method, and a closed-loop control method. The main cleaning gas is HFO-1447fz (CAS134190-34-8), accounting for 30% to 70% of the total molar fraction of the composition; the co-gas is selected from one or two of CF3I and C2F5I, accounting for 5% to 25% of the total molar fraction of the composition; the auxiliary regulating gas is selected from one or more of He, Ne, and Kr, accounting for 15% to 55% of the total molar fraction of the composition; the content of fluorine-containing unsaturated impurity compounds containing C=C or C≡C bonds in the cleaning gas composition is ≤0.08 mol. This invention uses HFO-1447fz as the main cleaning gas, combined with CF3I, C2F5I synergistic gases and rare gases for auxiliary regulation, to form a highly efficient cleaning system. The special molecular structure of HFO-1447fz can generate highly active fluorine radicals after plasma activation, which, together with the catalytic effect of iodine radicals, improves the removal rate of silicon-based dielectric deposits.

This invention provides an activation method for a liquid fatty amine, a preparation process for the liquid fatty amine and silane, wherein the liquid fatty amine has a tertiary amine group; the activation method involves activating the liquid fatty amine with silicon tetrachloride; this method can significantly improve the catalytic effect of the liquid fatty amine, and the activated liquid fatty amine exhibits higher catalytic activity in the process of disproportionation of trichlorosilane to prepare silane, which can effectively reduce the reaction activation energy, increase the reaction rate, and improve the single-pass reaction efficiency and conversion rate.

The invention relates to the technical field of catalysts, and provides a catalyst for synthesizing cyclic carbonate and a preparation method thereof.The catalyst for synthesizing cyclic carbonate comprises a carrier and ionic liquid loaded on the carrier; the carrier comprises porous carbon and epoxidized graphene in a mass ratio of (6-12): 1; the ionic liquid comprises one or two of imidazole salt ionic liquid and quaternary ammonium salt ionic liquid. According to the technical scheme, the problem that a catalyst for synthesizing cyclic carbonate in the prior art is poor in catalytic effect is solved.

The invention relates to the field of carbon dioxide capture, and provides a carbon dioxide absorbent pregnant solution double-tower cascade catalytic desorption system and method. The carbon dioxide absorbent rich liquor double-tower cascade catalytic desorption system comprises a low-temperature catalytic desorption tower, a solid acid catalyst packing layer is arranged in the low-temperature catalytic desorption tower, and an absorbent liquid outlet is formed in the tower bottom of the low-temperature catalytic desorption tower; the high-temperature thermal desorption tower is connected with the low-temperature catalytic desorption tower in series, a common filler layer without catalytic action is arranged in the high-temperature thermal desorption tower, and an absorbent liquid inlet is formed in the top of the high-temperature thermal desorption tower; an absorbent liquid outlet of the low-temperature catalytic desorption tower is communicated with an absorbent liquid inlet of the high-temperature thermal desorption tower through a pipeline, and the low-temperature catalytic desorption tower is used for conveying the absorbent subjected to low-temperature catalytic desorption to the high-temperature thermal desorption tower for high-temperature thermal desorption. According to the carbon dioxide absorbent pregnant solution double-tower cascade catalytic desorption system, the desorption temperature can be reduced, and the cyclic loading capacity of the absorbent can be ensured.

The application discloses a kind of Ni3InC for MgH2 hydrogen storage material 0.5 The application discloses a catalyst preparation method, (1) In(OH)3, Ni(OH)2, melamine are weighed at room temperature; the weighed In(OH)3, Ni(OH)2 and melamine are added to a crucible, and stirring is carried out with a glass rod; (2) the crucible in step (1) is placed in a tube furnace, and is heated to a certain temperature in a H2 atmosphere, and is naturally cooled to room temperature after heat preservation, to obtain black particles; (3) the sample obtained in step (2) is poured into a mortar for grinding, and Ni3InC 0.5 powder is obtained.The preparation method has the characteristics of low raw material cost, simple preparation process and obvious catalytic effect.

This invention relates to the field of water remediation technology, specifically to a piezoelectric catalytic component and a groundwater remediation system. The piezoelectric catalytic component includes: an upper part of a piezoelectric catalytic body with a spiral channel communicating with an inlet, and a lower part with a cavity; the cross-sectional diameter of the spiral channel gradually decreases from the inlet to the end; a column is provided in the cavity, and a piezoelectric film is spirally wound around the column; the end of the spiral channel is close to the piezoelectric film at the upper end of the column; the piezoelectric film receives water containing organic pollutants flowing in from the spiral channel and catalytically degrades the organic pollutants through piezoelectric conversion; this application combines the static pressure of the water flow, accelerates the water flow through the spiral channel, the flow velocity gradually increases from top to bottom, the hydraulic impact load is correspondingly enhanced, the mechanical force flowing through the piezoelectric film is increased, low-frequency vibration excites the piezoelectric catalytic effect, maximizes the catalytic degradation capacity of the piezoelectric material, and thus improves the catalytic degradation efficiency of the piezoelectric material.

This invention proposes a rapid condenser plugging method based on a mercapto-isocyanate click reaction. First, a mixture containing mercapto and isocyanate groups is prepared, and a catalyst is added to obtain a plugging agent suitable for plugging condenser heat exchangers. When plugging is needed, the plugging agent is added to the condenser heat exchange tubes. Under the dual catalytic action of the catalyst and water vapor within the heat exchange tubes, a rapid plugging effect is achieved. The rapid plugging method proposed in this invention features simple plugging agent preparation, a fast plugging process, and adaptability to various heat exchange tube sizes and different surface cleanliness levels. Furthermore, the presence of water vapor within the heat exchange tubes accelerates the solidification and plugging process of the mixture. This method, based on click chemical reaction for plugging, overcomes the shortcomings of traditional physical plugging techniques, improving plugging efficiency and effectiveness.

The present application relates to the technical field of molecular sieve preparation, and provides a surface silicon-rich binderless ZSM-5 molecular sieve catalyst and a preparation method and application thereof.The overall SiO2 / Al2O3 of the ZSM-5 molecular sieve catalyst is 86-203, the SiO2 / Al2O3 of a surface layer with a depth of 2-10 nm is 8-33% higher than the overall SiO2 / Al2O3; the acid strength measured by using Hammett indicator n-butylamine titration method is H0≤+2.27, and the content of surface acid sites is ≤0.02 mmol / g; and the ZSM-5 molecular sieve catalyst is a shaped body without amorphous phase.The surface silicon-rich binderless ZSM-5 molecular sieve catalyst provided by the present application does not contain inert adhesive, has extremely weak surface acidity, can improve the catalytic effect, and reduces the generation of by-products.In addition, the preparation method provided by the present application is simple in process and suitable for industrial production.