24 results about "Efficient catalyst" patented technology

The application discloses a method for producing formaldehyde at low temperature, and belongs to the technical field of formaldehyde production. The method comprises the following steps: preparing a high-efficiency catalyst by taking iron nitrate nonahydrate, ammonium molybdate tetrahydrate and lithium hydride as raw materials; feeding mixed gas of methanol and air into a reactor filled with the high-efficiency catalyst under the condition that the temperature is 250-280 DEG C; and collecting gas at the outlet of the reactor to complete the method for producing formaldehyde at low temperature. The embedding of lithium can expand the crystal lattices of the catalytic products, thereby generating a large number of oxygen vacancies, enhancing the electron-donating capacity, and enabling the adsorption of p-formaldehyde to be quickly dissociated and the active sites to be quickly reduced at a relatively low temperature, so that the activity of subsequent catalysis is ensured. The plasma treatment can increase the surface area and the number of active sites of the high-efficiency catalyst, and further improve the catalytic activity. The method for producing formaldehyde at low temperature can improve the conversion rate of methanol and the yield of formaldehyde at a relatively low temperature, and is helpful to reduce energy consumption and reduce the volatilization of Mo.

This application relates to the field of hydrosilylation, and in particular to a highly efficient catalyst for hydrosilylation reactions and its preparation method. This application provides a method for preparing a microcapsule-form catalyst, which first modifies methyl-terminated hydroxyl silicone oil with silazane, and then forms a microcapsule coating system with paraffin, thereby improving the release performance of the microcapsule coating system, so that the catalyst has low reactivity in the early stage of release, thereby improving the uniformity of the reaction process inside the silicone rubber, and thus improving the transparency and overall strength of the silicone rubber.

This invention relates to a composite catalyst containing phenolic hydroxyl and imidazole structures, and a cyanate ester resin system. The catalyst system of this invention comprises compounds containing imidazole and phenolic structures, along with transition metal compounds. The compounds containing imidazole and phenolic structures serve as the hydrogen source for the active hydrogen catalyst and as the support for the transition metal compound catalyst. The cyanate ester resin system of this invention is prepared by mixing cyanate ester resin, a toughening agent, and a high-efficiency catalyst. By using the catalyst, the curing reaction of the cyanate ester resin system is completed under medium-low temperature curing conditions while maintaining the excellent heat resistance of the cyanate ester resin. This cyanate ester resin system can be widely used in aerospace, military, and other fields such as projectile transparent covers, radar domes, satellite solar panels, and space support structures.

The application discloses a kind of by density functional theory reveals the calculation method of micro-mechanism and selectivity source of palladium catalysis olefin amine 1,2-diarylation reaction, belong to the intersection technical field of organic synthesis and computational chemistry. Including constructing molecular structure;The configuration optimization and calculation are carried out to molecular structure, obtain thermodynamic data;The geometric configuration of intermediate and transition state in each step is calculated, the change of gibbs free energy is obtained, the connection relationship of transition state and corresponding reactant, product is determined;According to thermodynamic data and connection relationship, reaction path diagram is drawn, and reaction mechanism is determined;According to reaction mechanism, the step of determining the selectivity of reaction region, enantioselectivity and chemical selectivity is determined, and selectivity control strategy is analyzed and output. By simulation, the key intermediate and transition state structure of each element step of reaction is determined, the reaction energy barrier of each element step is quantified, the transition state action mechanism determining the selectivity of reaction region, enantioselectivity and chemical selectivity is analyzed in depth, to provide theoretical guidance for the design of high-efficiency catalyst and the optimization of reaction condition.

This invention discloses a highly efficient method for synthesizing cyanuric acid in the field of green chemistry and chemical engineering. The method uses urea as a raw material and reacts it in a decahydronaphthalene solvent under the catalysis of a phosphotungstic acid-confined three-dimensional ordered macroporous alumina solid acid catalyst. Specifically, urea, solvent, and catalyst are mixed and heated under nitrogen protection. After cooling, filtration, and solvent washing, the resulting filter cake is separated from the crude product by stirring with hot water. The separated catalyst is dried and can be recycled. The filtrate containing the product is cooled, crystallized, filtered, washed, and dried to obtain high-purity cyanuric acid. The catalyst used in this method is prepared using a template method and confinement technology, exhibiting a stable structure and significantly inhibiting the loss of active components. This invention features a simple and efficient process, easy catalyst recovery and recycling, and high product yield and purity, demonstrating promising prospects for industrial application.

This invention belongs to the field of environmental engineering and electrocatalyst technology, and discloses a highly efficient catalyst for the electrocatalytic co-reduction of carbon dioxide and nitrate to urea, its preparation method, and its application. The catalyst is a Zn / MoO₂ catalyst. x -CNT composite catalyst, composed of carbon nanotubes supported on molybdenum oxide and zinc nanostructures supported on carbon paper, possesses the properties of Zn and MoO. x Heterogeneous interfaces, in which MoO x The catalyst is composed of molybdenum oxide, zinc nanoparticles, and carbon nanotubes as a support providing conductivity and structural stability. This invention constructs a heterojunction system and employs an electrochemical wet process to create a catalyst with numerous heterojunction interfaces. Through interfacial effects, it enhances electron transfer, regulation, and surface adsorption, effectively improving the efficiency and yield of the co-reduction of carbon dioxide and nitrate to urea. The preparation method is simple, easy to synthesize, uses inexpensive and readily available raw materials, and is easily scaled up, showing promising application prospects.

This invention belongs to the field of catalyst preparation technology, and discloses a low-silver-content ethylene oxide catalyst with a silver-rich surface, its preparation method, and its application. The method employs an economical and industrially applicable low-silver-content high-efficiency catalyst preparation system, innovatively using a "nebulized spray fluorine impregnation-calcination" process. By precisely controlling the penetration depth of fluorine on the alumina support surface through atomized solution, the calcined support forms a gradient structure of "surface lamellar alumina - internal dense alumina," providing support for the preparation of the surface-rich silver catalyst. Utilizing the high specific surface area and adsorption activity of the surface lamellar structure of the support, combined with the low adsorption of the internal dense structure, silver is preferentially enriched on the support surface during impregnation, forming a "surface-rich silver - internal-silver-poor" distribution state. This overcomes the technical bottleneck of low internal silver utilization caused by the uniform distribution of silver in traditional catalysts.

The application discloses a method for improving the polycondensation reaction rate of polyester material. The method uses dihydric alcohol and dicarboxylic acid and derivatives thereof as raw monomers, adds aromatic unit alcohol as a third component, sequentially carries out esterification reaction, pre-polycondensation reaction and final polycondensation reaction, and adds a high-efficiency catalyst in the pre-polycondensation reaction stage. In general, the addition of unit alcohol in the reaction will end the molecular chain of esterification product, which is not conducive to the growth of polymer chain and is generally used as a chain terminator. However, the esterification product is capped by adding aromatic unit alcohol in the esterification reaction stage in the application. Since the ester exchange activity of aryl ester is greater than that of aliphatic alkyl ester, the leaving ability of the aromatic unit alcohol is stronger in the polycondensation reaction, which is more conducive to improving the polycondensation reaction rate.

The application belongs to the technical field of electrochemical water decomposition, and discloses carbon-coupled nickel-iron bimetallic hydroxide and an in-situ rapid preparation method and application thereof. The in-situ rapid preparation method comprises the following steps: 1) dispersing two-dimensional titanium carbide loaded with single atoms in a water-ethanol mixed solution to obtain a suspension A; and 2) spraying the suspension A to the surface of a clean iron-nickel alloy, and air-drying, so that carbon-coupled nickel-iron bimetallic hydroxide is generated on the surface of the iron-nickel alloy by in-situ construction. The single atoms include one or more than one of Mn, Fe, Co, Ni, Cu and Ru. The method is convenient and efficient, and can realize the in-situ construction of carbon-coupled nickel-iron bimetallic hydroxide on the surface of the iron-nickel alloy in one step within 30 minutes, and is easy to scale up. The nickel-iron bimetallic hydroxide is applied as an efficient catalyst for oxygen evolution reaction in the field of electrochemical water decomposition, effectively improves the electron transmission efficiency inside the catalyst under industrial large current density, and reduces the oxygen evolution overpotential.

The application relates to the technical field of electrocatalytic material design, and particularly relates to a design method of a transition metal monatomic qHPC 24 supported catalyst for electrocatalytic nitrogen reduction reaction 24 The technical key points are as follows: a transition metal monatomic catalyst model of qHPC is constructed, after structure optimization, binding energy is calculated to complete stable anchoring screening, preliminary screening is implemented through N2 adsorption free energy calculation, then free energy change of NRR gradual protonation reaction path is analyzed to determine a decision step and calculate a theoretical overpotential to complete performance evaluation, finally, non-metal doping is carried out on the optimized catalyst, and stability and performance are re-evaluated, and a target catalyst is screened out, the application realizes quantitative screening and performance evaluation of multiple system catalysts, provides a feasible scheme for rational design and rapid screening of high-efficiency NRR catalysts, and greatly improves catalyst screening efficiency and design precision.

This invention discloses a cobalt-confined doping carbon-based catalyst for aminated lignin. The aminated lignin, after adsorbing cobalt, is reduced using sodium borohydride to reduce the adsorbed ⁺ to obtain a Co-NAL precursor. This precursor is then pyrolyzed at high temperature under an inert atmosphere to reconstruct the waste NAL-cobalt complex in situ into a cobalt-doped confined nitrogen-doped carbon catalyst. The catalyst has a specific surface area of ​​167.725 m² / g and a cobalt content of 46.54%. This invention is the first to innovatively utilize saturated aminated lignin adsorbents for high-value secondary use as catalysts, achieving a functional transformation from "adsorbent waste" to "high-efficiency catalyst," turning waste into treasure, and solving the problem of subsequent adsorbent disposal.

This invention discloses a combined process for the pretreatment of polyester waste and the preparation of dioctyl terephthalate in the field of polymer chemical recycling and resource recycling. The process utilizes specially formulated layered molybdenum-titanium bimetallic phosphate nanosheets with intercalation catalysis as a catalyst. The crushed polyester waste is mixed with isooctanol and pretreated at a lower temperature, followed by a catalytic alcoholysis and transesterification reaction. Ethylene glycol is continuously removed by fractional distillation to drive the reaction to completion. After the reaction, the mixture is cooled and filtered to separate the regenerable solid catalyst. The filtrate is then neutralized, washed with water, and subjected to two-step vacuum distillation. This process achieves a high degree of synergy between the catalyst and the reaction steps, simplifying the traditional multi-step complex process into four core steps. It has the advantages of mild reaction conditions, simple and efficient process, recyclable catalyst, and high product purity, providing a novel and practical technical solution for the high-value resource utilization of polyester waste.

The application belongs to the technical field of organic synthesis, and particularly relates to a high-efficiency synthesis method of symmetrical tri-sulfide compounds. The method for synthesizing tri-sulfide compounds by C-S coupling reaction of halide and elemental sulfur in an alkaline environment has low yield and poor selectivity. In view of the above problems, the application provides a synthesis method of symmetrical tri-sulfide compounds, which is obtained by C-S coupling reaction of halide, elemental sulfur, copper-based supported catalyst, acid binding agent and organic solvent. The copper-based supported catalyst is self-made, and has better selectivity for the target product symmetrical tri-sulfide compound and high product yield.

This invention discloses a method for constructing disulfide mimetic compounds for late cyclization of peptides. The disclosed method provides late cyclization via thioacetalization of peptides containing two cysteine ​​residues to form a thioacetal group. These bonds are stable under acidic, basic, and reducing conditions. A wide range of cyclic ketones, and even acetone, can be used as crosslinking agents in this reaction. Since trifluoroacetic acid (TFA) can function as both a catalyst and the sole solvent, most peptide sequences can be cyclized by the disclosed method. The disclosed method offers many advantages and merits, including the use of TFA as a robust catalyst and the sole required solvent, the readily available availability of acetone and a variety of cyclic ketones as reactants, good chemoselectivity and tolerance of natural peptides to this reaction, and the fact that the resulting crosslinks are structural mimetic compounds of disulfides.

This invention discloses a post-processing purification method for polycarbonate diols (PPCDL). The method uses water as a quencher and achieves efficient catalyst quenching and PPCDL stabilization through stepwise water addition, propylene oxide (PO) evaporation, and washing. The method includes: adding a small amount of water to the PPCDL solution to form a controllable and favorable microemulsion state; heating to evaporate residual PO; hot water washing to separate impurities; and vacuum drying to obtain the purified product. This method is simple, environmentally friendly, and low-cost, and can effectively prevent the degradation of PPCDL products, improve product purity and molecular weight stability, making it suitable for industrial production.

The application discloses a method for catalytic oxidation of manganese ions in drinking water, which belongs to the field of drinking water purification. Metal column swelling bentonite and free chlorine are added into a water solution containing Mn 2+ , stirred in a reactor, oxidized, separated and Mn 2+ in the water is removed; the metal column swelling bentonite serves as a high-efficiency catalyst, can provide a catalytic site, catalyze the rapid oxidation of Mn 2+ in the water by chlorine, has a high specific surface area and porosity, can provide a load for the oxidation product MnOx of Mn 2+ , and MnOx has a self-catalytic effect, accelerates the oxidation of Mn 2+ in the water into more MnOx, realizes the efficient removal of Mn 2+ , and can effectively remove pollutants such as bacteria, viruses and algae in the water, and the water after oxidation treatment is separated through precipitation, centrifugation or filtration, reaches the requirement of drinking water and has good water quality; compared with simple chlorine oxidation and a traditional manganese sand filter, the application can greatly shorten the reaction time and reduce the treatment space.

This invention relates to the field of producing mesitylene from reformed C9 heavy aromatics, specifically a method, apparatus, catalyst, and preparation method for producing mesitylene. The method for producing mesitylene includes removing C9 heavy aromatics from C9 heavy aromatics via a de-heavy tower. 10 The above-mentioned heavy components convert the separated C9 mixed aromatics into dealkylation isomerization products. These products undergo gas-liquid separation to obtain liquid hydrocarbon products, which are then separated in a distillation column. Light components are produced at the top of the distillation column, mesitylene is produced from the side stream, and the bottom product is returned to the heavy hydrocarbon removal column, achieving material recycling. This invention uses reformed C9 heavy aromatics as raw material, developing a highly efficient catalyst and reaction separation process to solve the interference of methyl ethyl benzene in existing processes, retain mesitylene, reduce by-product generation, increase mesitylene yield, improve catalyst stability, extend operating cycle, reduce mesitylene production costs, and enhance the utilization value of C9 mixed aromatics.

The application discloses a high-stability Ni@HAlBeta catalyst and a preparation and application thereof. The catalyst is prepared by mixing and grinding with acetylacetone nickel and calcining and reducing, and takes dealuminated beta zeolite as a carrier. A silanol nest structure of the HAlBeta carrier forms a strong metal carrier interaction with Ni, and sintering of the Ni is inhibited. Dealuminization treatment reduces the acidity of the carrier, and formation of encapsulated carbon and graphitic carbon is inhibited. The catalyst shows excellent performance in hydrogen production by biomass gasification. The preparation process is simple, and the cost is low, and the catalyst is suitable for various agricultural and forestry waste raw materials, and provides an efficient catalyst scheme for industrialization of a biomass gasification and hydrogen-rich synthesis gas technology.

The application belongs to the technical field of water treatment, and particularly relates to an ultrasonic-assisted micro-nano bubble dispersion and dissolution system for water treatment, which comprises an ozone generation unit, an ultrasonic generation unit, a micro-nano bubble generation unit, a circulating fluidized bed reaction unit and a temperature and pressure control unit. The ozone generation unit comprises an ozone generator, an ozone concentration detector and an ozone conveying pipeline, and the ozone concentration detector is arranged on the ozone conveying pipeline and used for monitoring the ozone concentration conveyed to the micro-nano bubble generation unit in real time. The application integrates the functions of ultrasonic-assisted micro-nano bubble generation, an efficient catalyst system, a circulating fluidized bed reaction and precise temperature and pressure control, realizes efficient dispersion and dissolution of ozone, strengthens the synergistic effect of adsorption and catalytic oxidation, significantly improves the removal efficiency of refractory organic pollutants in water, realizes cyclic utilization of ozone resources, and reduces operation cost and environmental risk.

This invention discloses a method for the precise design and efficient screening of diatomic catalysts based on MXenes for CO2RR. The method includes the following steps: 1. Initial support selection; 2. Model construction; 3. Electronic structure screening; 4. Stability assessment; 5. Catalytic activity screening; 6. Selectivity screening. This invention uses first-principles calculations combined with high-throughput screening to identify diatomic combinations suitable for MXenes. Through electronic locality function analysis and calculations of formation and binding energies, stable MXene-based diatomic catalyst models are selected. Their thermodynamic stability is verified through molecular dynamics. Catalytic activity studies show that the rate-limiting step for Pd2-Mo2CO2 catalyzing NRR is as low as 0.23 eV, and the overpotential for Au2-Ti2CO2 catalyzing CO2RR to ethanol is only 0.6 V, demonstrating superior performance compared to traditional catalysts. This method provides an efficient catalyst design paradigm for electrochemical energy conversion.