112 results about "Catalytic hydrogenation" patented technology

The present invention relates to a Ru-Ni bimetallic catalyst for the selective hydrogenation of a quinoline organic hydrogen storage carrier, and a preparation method therefor and the use thereof. In the catalyst, carbon nitride is used as a carrier, and metal nanoparticles Ru and Ni serve as active components and are jointly loaded on the carbon nitride carrier; and the carbon nitride is prepared by mixing carbon tetrachloride, ethidene diamine and nano-silica, reacting same to obtain a carbon nitride polymer, then calcining same at 750-850ºC, performing a desilicification treatment, and then filtering and drying same. The catalyst provided in the present application has good catalytic hydrogenation performance in the selective hydrogenation of the quinoline organic hydrogen storage carrier and can achieve the omission of a solvent in a reaction system; the reaction is simple, green and environmentally friendly, and the gravimetric hydrogen storage density of the system can be maximally ensured when a quinoline compound is used as an organic hydrogen carrier; moreover, the catalyst also has a good cycling stability.

The application discloses a catalyst for preparing methylaniline and a preparation method and application thereof, and belongs to the technical field of catalysts. The catalyst is prepared by modifying an activated carbon carrier with zirconium, cerium or nickel, treating the carrier with high-temperature nitrogen, loading active components Pd and pH-responsive polymers, solving the problems of low dispersion of the active components, easy poisoning and activity attenuation, and having good pH responsiveness and environmental adaptability. The preparation method optimizes a carrier modification process, adopts an impregnation method combined with timed stirring, controls reaction parameters, improves catalyst performance, realizes high selectivity and high yield of methylaniline, and has the advantages of high selectivity of the catalyst for methylaniline, inhibition of side reactions, adoption of a fixed bed reactor, simplification of operation, reduction of safety hazards, efficient reaction at a lower reaction temperature and pressure, and reduction of energy consumption and production cost.

This invention discloses a method for preparing and analyzing trans-4-aminocyclohexylacetic acid. The preparation method is as follows: 4-nitrophenylacetic acid undergoes catalytic hydrogenation in a solvent, followed by filtration. The filtrate is then treated with acid to obtain a 4-aminophenylacetic acid salt solution. The collected catalyst is activated. The 4-aminophenylacetic acid salt solution is mixed with isopropanol, barium hydroxide, tetrabutylammonium bromide, 18-crown ether-6, and dibutyl phthalate. The activated catalyst is then added to initiate a catalytic hydrogenation reaction. After the reaction, the reaction solution is cooled and filtered. The resulting solid is mixed with a preheated dilute sulfuric acid solution and stirred to form a slurry. The mixture is then filtered, and the filtrate is neutralized and filtered again. The collected filtrate is concentrated and crystallized. The crystallized precipitate is washed and dried to obtain trans-4-aminocyclohexylacetic acid. The method provided by this invention has high reaction efficiency, mild conditions, and is suitable for industrial production. It yields high product purity and reliability. Furthermore, the analytical method provided by this invention is accurate and reliable.

The application discloses transparent polyethylene-butylene rubber granules, a preparation method and application thereof. Butadiene monomers are obtained by an anionic polymerization method to obtain BR raw glue liquid, and the BR raw glue liquid is subjected to catalytic hydrogenation to obtain polyethylene-butylene glue liquid; after the polyethylene-butylene glue liquid is concentrated by falling film evaporation, the transparent glue particles (EBBR) with a volatile matter content of less than or equal to 0.35% (mass fraction) are obtained by deep devolatilization and extrusion granulation through a double screw extruder, the EBBR has the characteristics of a wide molecular weight, non-crystallization, good elasticity, high strength and low volatile matter, and has excellent physical properties after being blended with PP and vulcanized, and simultaneously has good processing performance.

This utility model relates to the field of hydrogenation catalyst preparation technology, and discloses a high-efficiency catalytic hydrogenation reaction device, including a base, a column fixedly connected to the upper surface of the base, a reaction vessel fixedly connected to the outer wall of the column, and a vibration assembly provided on the inner wall of the reaction vessel. The vibration assembly includes a guide plate, the outer wall of which is fixedly connected to the inner wall of the reaction vessel. A protective column and a spring are fixedly connected to the upper surface of the guide plate. A motor is provided on the inner wall of the guide plate, a connecting column is fixedly connected to the output end of the motor, a crank is fixedly connected to the outer wall of the connecting column, and a rotating shaft is rotatably connected to the outer wall of the crank. In this utility model, in order to prevent the problem of low reaction efficiency caused by uneven material distribution during the catalytic hydrogenation reaction, an innovative vibration guide system is used to ensure that the catalyst and reactants are fully contacted and mixed, significantly improving the reaction efficiency and product yield.

This invention discloses a magnetic Ni x％ This paper describes the preparation method and application of FeNb2O6 composite catalysts, which fall under the technical field of supported bimetallic oxide catalysts. First, magnetic FeNb2O6 nanocatalysts are prepared via a one-pot hydrothermal method using niobium oxalate hydrate as the niobium source and ferric nitrate as the iron source. Then, magnetic Ni is prepared via a modified deposition precipitation method using nickel nitrate as the nickel source and the magnetic FeNb2O6 nanocatalyst as the support. x％ @FeNb2O6 composite catalyst. The beneficial effect of this invention is that Ni... x％ In the FeNb2O6 composite catalyst, iron, niobium, and nickel species are highly dispersed with no obvious agglomeration, exhibiting high activity and high stability. Furthermore, the catalyst's magnetic properties allow for recovery and reuse, overcoming the shortcomings of traditional metal catalysts such as easy loss and difficulty in recovery after reaction. This Ni... x％ The FeNb2O6 composite catalyst is used for the catalytic hydrogenation conversion of Caragana korshinskii and its related model compounds. Due to its high C-O- bond cleavage activity, it can more effectively promote the depolymerization of Caragana korshinskii organic matter, thereby obtaining bio-oil rich in high-value COH functional groups.

The application discloses a green electricity consumption system and method for synthesizing methanol by CO2 hydrogenation through plasma catalysis. H2 obtained by electrolysis of water and CO2 captured in an industrial process are first subjected to a reverse water gas shift reaction under efficient driving of normal pressure jet plasma to obtain a CO / CO2 / H2 mixed product, the mixed product is subjected to multi-stage pressurization after passing through a buffer storage tank, and green methanol is further synthesized in a hot catalytic bed. The application adopts a two-stage methanol synthesis system of plasma CO2 pre-conversion and CO / CO2 catalytic hydrogenation, solves the problems of catalyst deactivation and excessively high reaction temperature in a traditional hot catalytic reverse water gas shift reaction, and overcomes a thermodynamic bottleneck of a CO2 direct catalytic hydrogenation reaction. The plasma reaction device has high energy efficiency and is quick to start and stop, can be directly driven by fluctuating power, and the system maintains the stability of the catalytic system through intermediate product storage and multi-stage pressurization.

This invention relates to a catalyst for the hydrogenation of carbon dioxide to methanol, its preparation method, and its application. The preparation method of the catalyst includes the following steps: (1) mixing an aqueous solution of zinc salt, zirconium salt, and gallium nitrate with an alkaline solution; aging; the mixing temperature is 65-85℃, the pH value is 8.2-11.5; the molar ratio of Zn to Zr is 0.15-1.0:1.0; (2) separating, drying, and calcining the aged product to obtain a catalyst precursor; (3) reducing the catalyst precursor to obtain a catalyst for the hydrogenation of carbon dioxide to methanol; the mass percentage of Ga in the catalyst is 1.0-2.0%. The technical problem to be solved is to provide a composite oxide catalyst of Ga, Zn, and Zr, in which the mass percentage of Ga is 1.0-2.0%. When used in the catalytic hydrogenation of carbon dioxide to methanol, it has a carbon dioxide conversion rate of 14.6-17.7% and a methanol selectivity of 80.1-83.6%, which is beneficial to the industrial-scale production of methanol by the hydrogenation of carbon dioxide.

This invention provides a method for preparing nano-sized magnesium hydride, comprising the steps of preparing magnesium nanoparticles by gas-phase condensation, MXene-confined catalytic hydrogenation, and atomic layer deposition to construct a composite coating layer. This invention achieves the preparation of ultrafine magnesium nanoparticles through gas-phase condensation; simultaneously utilizing the three-dimensional wrinkled structure Ti3C2T x MXene not only effectively prevents the migration and aggregation of nanoparticles during cycling through physical confinement, but also lowers the energy barrier of hydrogen adsorption and desorption reactions through in-situ generated highly active catalytic phases (such as TiH2), achieving a dual synergistic effect of confinement and catalysis. A titanium dioxide-amorphous carbon composite coating layer is constructed using atomic layer deposition (ALD) technology, which, in conjunction with the MXene confinement framework, provides a dual stabilization mechanism for nano-magnesium hydride. This invention organically combines gas-phase condensation, MXene-confined hydrogenation, and ALD coating, resulting in a product with an initial dehydrogenation temperature below 100°C and a hydrogen storage capacity retention rate exceeding 95% after 3000 hydrogen adsorption and desorption cycles, demonstrating excellent comprehensive performance.

The present invention relates to catalytic hydrogenation and the use of manganese-based catalysts, in particular to the catalytic hydrogenation of urea or its derivatives, or carbamates using manganese-based polydentate ligand compounds. The use of manganese-based polydentate ligand compounds for the above reactions is proposed for the first time.

The application discloses a preparation method of relugolix and belongs to the field of drug synthesis. The method uses 2-[(2,6-difluorobenzyl) n-propoxy amido]-4-(dimethylamino) methyl-5-(4-nitrophenyl) thiophene-3-carboxylic acid ethyl ester (formula II) as a starting material, and relugolix is prepared through the following steps: inorganic base hydrolysis, amide condensation, inorganic base cyclization, 10% Pd / C catalytic hydrogenation, and finally amide condensation with methoxyamino carbonic acid phenyl ester. The starting material used in the preparation method is cheap and easy to obtain, the reaction is mild, the operation is simple, the product has high purity and high yield, no biuret by-product is detected, and the method is suitable for industrial production.

The present application relates to the technical field of waste plastic chemical conversion, and discloses a waste plastic processing technology, which comprises the following steps: (1) contacting waste plastic, solvent I and a decontaminating agent, and performing heat treatment to obtain a product, and then performing solid-liquid separation to obtain liquid-phase material and solid-phase material; wherein the waste plastic comprises mechanical impurities, PVC and PS, and further comprises at least one of PE and PP; the decontaminating agent comprises an adsorption component and an acid-removing component; (2) performing catalytic hydrogenation on the liquid-phase material to obtain catalytic hydrogenation tail oil; (3) contacting the solid-phase material with solvent II to perform extraction and obtain extraction liquid; (4) recycling the extraction liquid to obtain recycled solvent II and PS; wherein the recycled solvent II is recycled to the extraction process. The waste plastic processing technology provided by the present application has mild reaction conditions, can solve the corrosion problem of HCl, reduce the content of Si in the hydrogenation tail oil, is beneficial to improving the yield of the hydrogenation tail oil, and can obtain high-quality hydrogenation tail oil.

A method for producing and purifying aliphatic primary diamines and a chemical reaction unit for producing aliphatic primary diamines are provided, wherein the method comprises the steps of: a) reacting an aliphatic dinitrile and a hydrogen-containing gas in the presence of a catalyst in a reaction unit R1 to form a medium M1 containing aliphatic primary diamines, and b) subjecting a stream F1 generated by the medium M1 to a distillation sequence comprising distillation steps to recover a first fraction and a second fraction containing aliphatic primary diamines in purified form, wherein the second fraction is subjected to a catalytic hydrogenation step, or the second fraction is subjected to a further distillation step to recover a third fraction, wherein the third fraction is subjected to a catalytic hydrogenation step.

The application provides a synthesis method of agomelatine. The starting material I is reacted with SOCl2 to obtain acyl chloride under the action of a solvent A, and then reacted with NH4OH to obtain intermediate I; the intermediate I is reacted with (CF3CO)2O under the action of a solvent B and triethylamine to obtain intermediate II through dehydration; the intermediate II is subjected to catalytic hydrogenation reaction with Raney Ni and H2 under the action of a solvent C to obtain intermediate III; the intermediate III is reacted with HCl under the action of a solvent D to obtain intermediate IV; and the intermediate IV is condensed with CH3COCl under the action of a solvent E and Cs2CO3 to obtain agomelatine. The method is simple in operation, mild in reaction condition, high in yield, low in cost, friendly to the environment, and suitable for industrial large-scale production of agomelatine.

This invention discloses a heterogeneous nanocatalyst for the catalytic hydrogenation of CO2 to methanol and its preparation method. The catalyst precursor comprises a CuO-ZnO composite oxide and highly dispersed Ga, which, after reduction activation, forms a heterogeneous interface structure composed of metallic Cu, ZnO, and Ga. The preparation includes: preparing the CuO-ZnO composite oxide using a co-precipitation method, then ball-milling and mixing it with solid metallic Ga to obtain the precursor, and finally activating it through in-situ photoreduction. This catalyst, when used in the CO2 hydrogenation reaction under photothermal synergistic conditions, significantly improves catalytic activity and methanol selectivity through multi-component interfacial synergy and photothermal effects.

This invention discloses a compound of formula I and a method for preparing minocycline hydrochloride. The method for preparing compound I involves dissolving 6-demethyltetracycline in acidic water, adding a chlorination reagent for chlorination, then adding p-aminobenzenesulfonic acid diazonium hydrochloride and alkaline solution for coupling reaction, followed by post-treatment. The method for preparing minocycline hydrochloride uses 6-demethyltetracycline as a starting material, proceeding through the intermediate of compound I, and removing the C7 chlorine, p-aminobenzenesulfonic acid group, and C6 hydroxyl group via catalytic hydrogenation, followed by reductive amination and post-treatment. This invention achieves low-pressure palladium-carbon catalytic removal of the C6 hydroxyl group by introducing an electron-donating amino group at the C7 position, eliminating the need for expensive rhodium-carbon catalysts. The reaction conditions are mild, column chromatography purification is unnecessary, the overall yield is ≥85%, and the product purity is ≥96%, making it suitable for industrial production.

This invention discloses a method for synthesizing a bifunctional PdCu catalyst for electrocatalytic hydrogenation-coupled oxidation of HMF. The method involves chemically oxidizing a copper foam framework to induce in-situ growth of nanowire structures on the surface of the copper foam nanowire substrate. A palladium salt is used as the palladium source and loaded onto the copper foam nanowire substrate in a cluster form. The prepared catalyst possesses a nanowire structure that facilitates the loading of Pd clusters, generating more active sites. The Pd clusters provide active hydrogen (H*) to accelerate electron transport, thereby achieving efficient hydrogenation of high-concentration HMF to BHMF at the cathode. Simultaneously, when applied to the anode, it enables efficient HMF conversion to FDCA. This material is suitable for the continuous production of high-value-added products FDCA and BHMF through electrocatalytic hydrogenation-coupled oxidation. The catalyst exhibits high activity, high stability, and high electron utilization, demonstrating significant potential for industrial application.

This invention belongs to the field of fine chemical synthesis technology and relates to a method for preparing 2,4-diaminodiphenylamine, an intermediate in p-phenylenediamine antioxidants. Aniline and m-dinitrobenzene undergo a catalytic nucleophilic substitution reaction under negative pressure to obtain a reaction system with 2,4-dinitrodiphenylamine as the main product. The reaction system with 2,4-dinitrodiphenylamine as the main product is diluted with methanol and then subjected to catalytic hydrogenation. After the reaction, post-treatment yields 2,4-diaminodiphenylamine. This invention uses m-dinitrobenzene as the reactant, which is halogen-free and does not produce halogen-containing wastewater. It also has lower requirements for the corrosion resistance of production equipment, higher atom economy, and is more in line with the concept of green chemistry. The solvent and catalyst in this invention are recyclable, resulting in low cost.

This invention discloses a method for preparing diesel fraction from waste tire pyrolysis oil via catalytic hydrogenation, and the resulting diesel fraction, belonging to the field of solid waste resource utilization and petroleum hydrorefining technology. This invention addresses the problems of high sulfur, nitrogen, and gum content in waste tire pyrolysis oil, easy catalyst deactivation in laboratory trials, difficulty in controlling the hydrogenation upgrading effect, and the inability of the product to consistently meet the China VI standard. The method first removes solid slag, heavy gum, and moisture through a stepped pretreatment process to obtain refined raw materials. Then, hydrogenation upgrading is completed in an intermittent high-pressure reactor using a pre-sulfurized hydrogenation catalyst. Finally, the target product is obtained through fractionation. This invention's process is compatible with conventional laboratory equipment, is safe and controllable, and the core indicators of the product diesel fraction fully comply with the China VI b automotive diesel standard.

The application provides a method for synthesizing 2,4,4-trimethyl-2-pentanol from diisobutene by esterification hydration, comprising the following steps: S1, esterification hydration reaction: diisobutene, organic acid and water are reacted in the presence of a catalyst; S2, separation and recovery: S3, hydrogenation reaction: 2,4,4-trimethyl-2-pentyl acetate recovered in step S2.5 is subjected to catalytic hydrogenation to generate a hydrogenation reaction liquid containing 2,4,4-trimethyl-2-pentanol and ethanol; S4, the hydrogenation reaction liquid obtained in step S3 is separated, and TMPOL is synthesized by using the above method with the organic acid as a medium, the single-pass conversion rate of diisobutene can reach 50%, and the selectivity reaches 99%. The process has the characteristics of high efficiency and high atom economy, and has great industrialization potential.

This invention discloses an In-Co-Zr composite catalyst, its preparation method, and its application, relating to the technical field of hydrogenation catalysts. The In-Co-Zr composite catalyst comprises an In₂O₃ support and an active component and structural promoter Zr supported on the In₂O₃ support, wherein the active component includes CoIn. x and Co3InC 0.75 The molar ratio of In, Co, and Zr in the composite catalyst is (1-9):(1.5-2.5):1. The In-Co-Zr composite catalyst exhibits a uniform distribution of active components and a high density of active sites. In the catalytic hydrogenation of CO2 to methanol, it can improve CO2 conversion while ensuring high methanol selectivity, and also possesses good heat resistance and anti-sintering properties. Under reaction conditions of 310℃, the CO2 conversion rate reaches 17.4% and the methanol selectivity reaches 77.7% during the catalytic hydrogenation of CO2 to methanol.

This invention discloses a method for the catalytic hydrogenation of bio-based small molecule diols to prepare monohydric alcohols. The method includes the following steps: placing an aqueous solution of a bio-based small molecule diol in a high-pressure reactor, adding an activated carbon-supported metal catalyst and a solid or liquid acid, then introducing hydrogen gas at a certain pressure, and stirring the reaction at a certain temperature for a period of time to obtain the monohydric alcohol; the small molecule diol is one of ethylene glycol, 1,2-propanediol, 1,4-butanediol, 1,2-pentanediol, 1,5-pentanediol, and 1,2-hexanediol; the activated carbon raw material is widely available, easy to prepare, and recyclable. The catalyst preparation process is simple, reusable, inexpensive, has high catalytic activity, and the reaction conditions are relatively mild, making it easy to promote.

The application discloses a kind of squalene continuous flow catalytic hydrogenation squalane application alumina ball load palladium catalyst and its preparation method, the catalyst with gamma-alumina ball as carrier, modification impregnation method load palladium active component, with auxiliary control interface effect, form high dispersion Pd / Al2O3 Catalytic system, palladium loading is 0.01wt%-5wt%.The catalyst is filled in fixed bed reactor, and is applied to squalene continuous flow hydrogenation preparation squalane reaction, using continuous flow hydrogenation process, under mild conditions, squalene can be realized efficient conversion, conversion rate is ≥99%, squalane selectivity is ≥99%.The present application solves the problems of low selectivity, low utilization rate of noble metal and poor stability of existing squalene hydrogenation catalyst, and the problems of low efficiency and difficult industrial continuous production of traditional batch hydrogenation process.The process conditions are mild, environmentally friendly and suitable for industrial application.Compared with traditional Pd / C catalyst, the catalyst has higher activity and stability.

The application discloses a preparation method of a multi-stage hole composite molecular sieve catalyst for catalytic hydrogenation and a method for preparing bio-jet fuel by hydrogenating microalgae oil, and belongs to the technical field of preparing bio-jet fuel from microalgae oil. The multi-stage hole composite molecular sieve catalyst comprises a composite carrier and an active metal component loaded on the composite carrier. The preparation of the composite carrier in the catalyst is based on an in-situ symbiotic composite method, the combination of the treatment of SAPO-11, a prepolymer and an additive in a molecular sieve is used to realize uniform transition of the pore and improve the interface bonding force, the service life and the catalytic effect of the catalyst are improved, the content of isomerization products in the bio-jet fuel is improved, and the freezing point reaches the standard.

The application belongs to the technical field of catalysts for nitroarene derivative hydrogenation reaction, and particularly relates to a high-selectivity Pt-based catalyst and a preparation method and application thereof. A carrier material and chloroplatinic acid ethylene glycol solution are added into ethylene glycol, and pH is adjusted to 5-6, heating reaction, centrifugation, washing, and drying to obtain a precursor catalyst loaded with metallic Pt nanoparticles; the precursor catalyst loaded with metallic Pt nanoparticles is subjected to heat treatment under an oxygen-containing atmosphere to obtain the high-selectivity Pt-based catalyst. The low-coordination Pt atoms are induced by heat treatment of the precursor catalyst loaded with metallic Pt nanoparticles under the oxygen-containing atmosphere, so that the selectivity of the Pt-based catalyst in the catalytic hydrogenation reaction of nitroarene derivatives is improved.

This invention discloses a highly efficient method for synthesizing proxalutamide intermediates, belonging to the field of pharmaceutical synthesis technology. First, dimethyl malonate and 2-chloro-5-nitropyridine are used as raw materials, condensed in the presence of potassium carbonate to generate dimethyl 2-(5-nitropyridine-2-yl)malonate. This is then reacted with tert-butyl acrylate and acid-hydrolyzed to obtain 4-(5-nitropyridine-2-yl)butyric acid. After activation with N,N'-carbonyl diimidazole, it is coupled with aminoacetaldehyde dimethyl acetal to form N-(2,2-dimethoxyethyl)-4-(5-nitropyridine-2-yl)butyramide. Then, a cyclization reaction mediated by phosphorus pentoxide and methanesulfonic acid is used to generate crude 2-(3-(5-nitropyridine-2-yl)propyl)oxazole. After purification, the nitro group is reduced by catalytic hydrogenation, and finally, it reacts with 1,5-naphthalenedisulfonic acid to form a salt, yielding the proxalutamide intermediate. This method achieves highly efficient synthesis of proxalutamide intermediates.

Disclosed in the present invention is an asymmetric catalytic hydrogenation method for a cyclohexene derivative, comprising the following steps: under a hydrogen atmosphere, the cyclohexene derivative undergoes an asymmetric hydrogenation reduction reaction in the presence of a catalyst, an acid and a solvent. The asymmetric catalytic hydrogenation method provided by the present invention achieves high conversion and excellent selectivity for a cyclohexene derivative substrate, and the resulting reduction product has a high ee value of up to 99%, and is suitable for industrial scale-up production. The method can effectively improve the production efficiency and product purity, thereby meeting the requirements of large-scale production.