981 results about "Hydrogen atmosphere" patented technology

The invention discloses a preparation method of a CuZnAlGa hydrotalcite-like derivative catalyst for preparing methanol from synthesis gas rich in carbon dioxide. Cu metal salt, Zn metal salt, Al metal salt and Ga metal salt are used as precursors, Na2CO3 and NaOH are used as precipitants, a mixed alcohol-water solution is used as an auxiliary solvent for coprecipitation, constant temperature and pH value are controlled, and a hydrotalcite-like structure catalyst precursor is obtained. And the precursor is subjected to high-temperature roasting and in-situ reduction in the hydrogen atmosphere, and then the layered framework structure with the Cu nano-particles fixed by the oxide is obtained. The hydrotalcite-like structure plays a role in crystal lattice confinement to prevent Cu particle aggregation, and the interaction between Cu and the oxide improves the adsorption capacity of the surface of the catalyst to CO and CO2, and enhances the activity and stability of methanol prepared from carbon dioxide-rich synthesis gas.

The invention belongs to the field of waste artificial graphite regeneration, and particularly relates to a waste artificial graphite regeneration method, a regenerated material and application thereof, the regeneration method comprises the following steps: carrying out normal pressure liquid phase modification on waste artificial graphite in an organic acid solution in advance, and then putting the modified waste artificial graphite in an inorganic acid solution for positive pressure liquid phase modification to prepare a modified material; mixing the modified material with a Mn source, a metal N source, a first carbon source and a binder to obtain a mixture, then performing heat treatment on the mixture in a hydrogen-containing atmosphere, and then performing negative-pressure annealing treatment to obtain a heat-treated material; the metal N source comprises a compound of at least one of iron, cobalt and nickel; and mixing the heat-treated material with lithium salt and a second carbon source, and carrying out roasting treatment to obtain the graphite regenerated material. The regeneration method disclosed by the invention is particularly suitable for repairing the artificial graphite waste which is difficult to treat, so that the artificial graphite waste can be repaired to obtain a material with excellent capacity, long circulation and particularly low-temperature stability.

This invention discloses a method for preparing a CuZnAlGa-based layered double hydroxide (TLH)-derived catalyst for methanol production from carbon dioxide-rich syngas. Using Cu, Zn, Al, and Ga metal salts as precursors, Na₂CO₃ and NaOH as precipitants, and a mixed alcohol-water solution as an auxiliary solvent, co-precipitation is performed under controlled temperature and pH to obtain a LDH-like catalyst precursor. After high-temperature calcination and in-situ reduction in a hydrogen atmosphere, a layered framework structure of Cu nanoparticles immobilized by oxides is obtained. The LDH-like structure provides lattice confinement, preventing Cu particle aggregation, and the interaction between Cu and the oxides enhances the catalyst surface's adsorption capacity for CO and CO₂, thereby improving the activity and stability of methanol production from carbon dioxide-rich syngas.

The invention belongs to the technical field of quartz glass, and discloses a synthetic quartz glass hydrogen loading method, which comprises: carrying out a first-stage heat treatment on synthetic quartz glass in a hydrogen atmosphere, carrying out a second-stage heat treatment in a vacuum atmosphere, and finally carrying out a third-stage heat treatment in a hydrogen-containing atmosphere so as to obtain the hydrogen-containing synthetic quartz glass. The hydrogen loading method is simple in step, quartz hydrogen loading can be completed within a short time, and the concentration of hydrogen molecules in the synthetic quartz glass meets characteristic distribution, so that the obtained hydrogen-containing synthetic quartz glass has excellent refractive index uniformity and ultraviolet radiation resistance.

The invention belongs to the field of OER catalysis, and particularly discloses a preparation method of a perovskite-based composite catalyst for surface in-situ desolvation of cobalt-iron-nickel ternary alloy nanoparticles, a perovskite precursor material with the expression formula of A-site defects being A1-xBO3-delta is obtained, and then the perovskite precursor material is roasted in a hydrogen-containing atmosphere at the temperature of 340-410 DEG C to obtain the perovskite-based composite catalyst for surface in-situ desolvation of cobalt-iron-nickel ternary alloy nanoparticles, in the A1-xBO3-delta, A is alkaline earth or a rare earth metal element, B comprises Co, Fe and Ni, and x is more than or equal to 0.85 and less than 1. The invention also comprises the catalyst prepared by the preparation method and the OER catalytic application of the catalyst. The preparation method provided by the invention can be used for preparing materials with special physicochemical and structure and excellent OER catalytic activity.

The invention provides a preparation method of a Cu-based catalyst for acetalation reaction, which comprises the following steps: depositing Pt on the surface of a pretreated carbon carrier through an atomic layer deposition method, depositing a metal oxide CuOx on the surface of the metal Pt, and performing high-temperature reduction and medium-temperature oxidation treatment to obtain the Cu-based catalyst. According to the method, the size of Pt particles and the thickness of CuOx can be accurately controlled on the atomic scale. The catalyst is applied to the acetalation reaction of aldol, the size of Pt particles and the thickness of CuOx can be accurately controlled on the atomic scale in the hydrogen atmosphere, the Pt-coated CuOx core-shell structure catalyst with cuprous as the main component is obtained on the surface of the carbon carrier, and the catalyst has the catalytic performance of high acetal yield due to the stable cuprous structure. The preparation of the catalyst is simple and controllable, and the greenization of the aldol acetalation reaction process and the high efficiency of the product are realized through the catalyst.

The invention discloses a lubricating oil preparation method, which comprises: contacting a raw material containing waste rubber with a catalyst in a closed container in a hydrogen atmosphere, and carrying out a catalytic cracking reaction to obtain a lubricating oil-containing product, the catalyst comprises a carrier, an acidic component and an active component loaded on the surface of the carrier, the active component is selected from at least one of a ruthenium elementary substance, a rhodium elementary substance, a platinum elementary substance, a palladium elementary substance, an iridium elementary substance and a nickel elementary substance; the acidic component is selected from at least one of silicotungstic acid, ammonium metatungstate, phosphotungstic acid and tungstic acid. The invention discloses a new path for preparing the lubricating oil by utilizing the waste rubber through a carbon = carbon hydrogenation and carbon-carbon bond breakage strategy under a relatively mild condition. According to the path, new application of waste rubber catalytic conversion is developed through C = C hydrogenation and C-C bond fracture strategies, and a new method for synthesizing lubricating oil with important application value is provided.

The invention discloses a method for reducing and decomposing ardealite under the assistance of hydrogen, which comprises the following steps: mixing crushed and sieved ardealite and lignite, placing the mixture in a tubular furnace, and reacting for 1-2.5 hours in a hydrogen atmosphere with the volume concentration of 20-100% at 700-800 DEG C to obtain a calcium sulfide product; according to the method, efficient resource utilization of the phosphogypsum can be achieved, meanwhile, the emission amount of CO2 is greatly reduced, and the method is simple and easy to implement and can play a reference role in industrial production and market popularization and application.

The invention discloses a high-entropy alloy system high-temperature brazing filler metal and a preparation method and application thereof, and relates to the technical field of welding materials.The preparation method comprises the following steps that iron powder, cobalt powder, nickel powder, copper powder and molybdenum powder are weighed and evenly mixed, and mixed metal powder is obtained; the mixed metal powder is put into a first ball milling tank, argon is introduced, ball milling is conducted for at least 15 h, and alloyed powder is obtained; the alloyed powder is put into a mold and sintered in the hydrogen atmosphere at the temperature of 1000-1200 DEG C, and a sintered blank is obtained; the sintered briquette is crushed into particles, the particles are put into a second ball milling tank, ball milling is conducted for at least 20 h in the argon atmosphere, and high-entropy alloy powder is obtained; and weighing the high-entropy alloy powder, borax and polyvinyl alcohol, and uniformly mixing to obtain the high-entropy alloy system high-temperature brazing filler metal. The prepared high-entropy alloy system high-temperature brazing filler metal has the advantages of being good in component uniformity, high in performance stability and excellent in wettability and filling performance, and the welding quality of a brazed joint can be effectively guaranteed.

The invention discloses an annular furnace heat-resistant supporting forged chassis and an additive manufacturing process and a fixing device thereof, and belongs to the technical field of plating of metal materials, and the annular furnace heat-resistant supporting forged chassis comprises the steps that heat-resistant alloy steel base metal with specific components is prepared; carrying out laser texturing and nickel-based alloy bottom layer pretreatment on the surface of the steel plate; performing laser cladding on high-silicon high-temperature alloy powder containing niobium and rare earth elements to form a functional cladding layer, and performing gradient cladding on the edge of the atmosphere guide hole; and finally, carrying out heat treatment and assembling with a fan-shaped refractory brick fixing device. A composite oxide film and a multi-scale strengthening system are constructed, hydrogen resistance and brittleness resistance are effectively achieved, interface thermal stress is relieved, cracking and stripping of a cladding layer are avoided, a fixing device adapts to thermal expansion, the atmosphere is dredged, and the annealing uniformity of a steel coil is improved; the problems of creep deformation, hydrogen embrittlement, cladding layer stripping and thermal stress cracking of a traditional supporting component under the conditions of high temperature, heavy load and nitrogen and hydrogen atmosphere are solved.

The invention discloses a method for preparing cyclohexylamine based on reductive amination of cyclohexanone, and belongs to the technical field of fine chemical engineering. The preparation method comprises the following steps: adding a reactant cyclohexanone into a reaction kettle containing a certain amount of solvent, ammonia water and hydrogen atmosphere, and carrying out reductive amination reaction in the presence of a catalyst to obtain cyclohexylamine. The catalyst is CoyAl-LDHs loaded with metal active components, the CoyAl-LDHs are layered cobalt-aluminum bimetal hydroxides, and cobalt ions and precious metal ions in laminates are subjected to spontaneous oxidation-reduction reaction, so that the precious metal ions can be efficiently reduced into active metal nanoparticles. The layered cobalt-aluminum double-metal hydroxide not only has abundant surface acid-base sites, but also has high dispersity of loaded metal nanoparticles. The catalyst preparation and reductive amination reaction conditions are mild, the yield is high, the reaction system is simple and easy to separate, and the method is suitable for industrial production of cyclohexylamine.

The invention discloses a multilayer nanostructure metal hydride and a preparation method thereof.The preparation method comprises the steps that transition metal ion salt and a carbon material are added into a polar solvent to be mixed, heating and stirring are conducted to obtain solid powder, and the solid powder is subjected to a hydrogen thermal reduction reaction to obtain a functionalized carbon material; a metal hydride raw material and a functionalized carbon material are added into an organic solvent, ultrasonic treatment and mixing are carried out, a mixed solution is obtained, and the metal hydride raw material is a mixture of an alkyl metal Mg compound or an alkyl metal Li compound and a borane compound; and in a hydrogen atmosphere, carrying out solvothermal reaction on the mixed solution, and then centrifuging, washing, filtering and drying to obtain the multilayer nanostructure metal hydride. The multilayer nano-structure metal hydride prepared by the preparation method has relatively high hydrogen absorption and hydrogen storage capacity.

The invention relates to the technical field of nano powder material preparation, in particular to a method for preparing molybdenum powder based on a spray granulation precursor and the molybdenum powder. The method for preparing the molybdenum powder comprises the steps that ammonium molybdate and a pore forming agent are dissolved in ultrapure water at the room temperature, and mixed slurry is obtained; carrying out spray granulation treatment on the mixed slurry to obtain composite powder particles containing the pore-forming agent and ammonium molybdate; the composite powder particles are placed in an oxygen-containing atmosphere to be roasted, and superfine nano molybdenum trioxide is obtained; placing the superfine nano molybdenum trioxide in a hydrogen atmosphere for primary reduction treatment to obtain superfine molybdenum dioxide powder; and the superfine molybdenum dioxide powder is subjected to second-stage reduction treatment, the superfine molybdenum powder is obtained, and the reduction conditions of the first-stage reduction treatment and the second-stage reduction treatment are different. According to the preparation method, the superfine molybdenum powder with good uniformity and dispersity can be prepared.

This invention belongs to the field of high-value utilization technology of biomass resources, and discloses a method for catalyzing the depolymerization of lignin into phenolic compounds using a RuNiZn / Nb2O5 catalyst. The method includes: uniformly mixing the RuNiZn / Nb2O5 catalyst, lignin-containing biomass feedstock, and water; stirring under hydrogen atmosphere to carry out the depolymerization reaction; after the reaction, cooling to room temperature and performing solid-liquid separation; evaporating the solvent to obtain the hydrogenated depolymerization product containing monophenols. In this invention, the RuNiZn / Nb2O5 catalyst employs a technique of replacing precious metals with various non-precious metals, which improves the catalyst's reactivity and reduces the amount of precious metals used. This increases the yield of lignin depolymerization products, provides milder depolymerization reaction conditions, and ultimately significantly reduces the catalyst preparation cost and the energy cost of the lignin depolymerization process.

The invention relates to a platinum-based catalyst for preferential catalytic oxidation of carbon monoxide in a hydrogen-rich atmosphere and preparation and application thereof, the composition of the catalyst is Pt / M1-M2Ox, Pt is an active component, and the content of Pt is 0.10-5.00 wt.%; m1 is an auxiliary agent and is selected from one or more of Fe, Co, Ni, Cu and Zn oxides, and the mass fraction of M1 in the catalyst is 0.01-5.00 wt.%; the carrier is M2Ox oxide, and M2 is one of Zr, Ti, Al and Si. Compared with the prior art, the Pt / M1-M2Ox catalyst has the advantages that the chemical state of the noble metal is adjusted by the aid of the aid M1, and the Pt / M1-M2Ox catalyst has excellent CO-PROX reaction activity and stability. The preparation method has the characteristics of simplicity in operation, high stability, good repeatability and the like.

The invention discloses a preparation method of chloroprocaine hydrochloride, and belongs to the technical field of chloroprocaine hydrochloride synthesis. Comprising the following steps: (1) preparing 4-amino-2-chlorobenzoic acid: dissolving 2-chloro-4-nitrobenzoic acid in a solvent, and uniformly stirring; adding a ruthenium catalyst Ru / SNC into the system, and carrying out heat preservation reaction in a hydrogen atmosphere; the 4-amino-2-chlorobenzoic acid is obtained through a reaction; (2) preparation of chloroprocaine hydrochloride: dissolving 4-amino-2-chlorobenzoic acid, 2-chloroethyl diethylamine and a solid base catalyst K / r-GO in a reaction solvent, and carrying out an esterification reaction; the 2-(diethylamino)-2-chlorine-4-nitrobenzoic acid ethyl ester is obtained; and then salifying and drying to obtain the chloroprocaine hydrochloride. The catalyst provided by the invention realizes efficient catalytic reaction at lower temperature and pressure, can be recycled for dozens of times, and is suitable for large-scale industrial production.

The invention provides a preparation method of a composite substrate for semiconductor device production, which comprises the following steps: putting raw material carbon into a reaction chamber in a hydrogen atmosphere, vacuumizing the reaction chamber, heating to 1000-1500 DEG C, such as 1000 DEG C, 1200 DEG C and 1500 DEG C, preserving heat for 1-3 hours, cooling and cleaning to obtain a carbon substrate; grinding and mixing a tantalum source, a tantalum fluoride and a fluxing agent to obtain coating powder; transferring the coating powder into a reaction chamber with a pulsed electric field, carrying out pulsed electric field assisted vapor deposition, and cooling to obtain a tantalum carbide pre-coating material with directionally arranged crystal orientations; and transferring the tantalum carbide pre-coating material into a high-temperature sintering furnace, and heating the tantalum carbide pre-coating material in an inert atmosphere at 1800-2400 DEG C for 0.5-6 hours to obtain the composite substrate which is used for producing a semiconductor device. Through directional arrangement of crystal orientations, the tantalum carbide coating achieves higher electrical conductivity and thermal conductivity.

The invention belongs to a preparation method of a chemical intermediate, and particularly relates to a preparation method of dimethyl 1, 4-cyclohexanedicarboxylate, which comprises the following steps: carrying out hydrogenation reaction on dimethyl p-toluene in a solvent in a hydrogen atmosphere under the catalysis of a cerium dioxide loaded ruthenium monometal catalyst to obtain the dimethyl 1, 4-cyclohexanedicarboxylate, the invention discloses a method for preparing dimethyl 1, 4-cyclohexanedicarboxylate from dimethyl terephthalate through hydrogenation, which comprises the following steps: under the catalysis of a ruthenium-containing catalyst taking cerium dioxide as a carrier, carrying out hydrogenation reaction on dimethyl terephthalate in a solvent in a hydrogen atmosphere to obtain dimethyl 1, 4-cyclohexanedicarboxylate, and separating the dimethyl 1, 4-cyclohexanedicarboxylate from dimethyl terephthalate to obtain dimethyl 1, 4-cyclohexanedicarboxylate. And after the reaction is completed, the high-purity dimethyl 1, 4-cyclohexanedicarboxylate can be obtained only by filtering out the catalyst and concentrating to remove the solvent, and the operation is simple and convenient.

A residual oil conversion process method and a reaction system belong to the field of oil refining processing, and the process method comprises the following steps: mixing a heavy inferior residual oil raw material with a dispersed molybdenum-containing catalyst and a partially circulated heavy fraction cracking product; after heat exchange and temperature rise, pretreatment is conducted through a 10-30 KHz ultrasonic device; after preheating, entering a slurry bed hydrogenation reactor, and carrying out a hydro-conversion reaction in a hydrogen atmosphere under the conditions of 380-500 DEG C and 5-18 MPa; after subsequent processes and equipment separation, the heavy liquid hydrocarbon part enters a catalytic cracking device and is subjected to a contact reaction with a residual oil cracking catalyst containing aluminum extraction and silicon supplement Y zeolite under the conditions that the temperature is 500-540 DEG C and the catalyst-oil ratio is 5-15; fractionating the product in a fractionating tower; the reaction system comprises an ultrasonic pretreatment device, a slurry bed reactor, a catalytic cracking device, a product fractionating tower and heat exchange, separation and circulation equipment. According to the method, the conversion efficiency and process stability of the heavy inferior residual oil raw material are improved, the yield of light fraction gasoline is increased, the energy consumption is reduced, and the method has good economical efficiency and practicability.

The invention belongs to the technical field of compounds, and provides a preparation method of 2-methyl-L-leucine hydrochloride. The method comprises the following steps: dissolving 2-amino propionate or hydrochloride thereof, an aldehyde ketone compound and alkali in a first solvent, heating for reaction, reacting with a chiral biphenyl quaternary ammonium salt phase transfer catalyst, performing deprotection reaction, performing catalytic hydrogenation reaction in a hydrogen atmosphere, and finally performing ester hydrolysis reaction to obtain the 2-methyl-L-leucine hydrochloride. The raw materials needed by the method are easy to obtain, the used catalyst and solvent can be used mechanically by 90% or above, the stereoselective chiral biphenyl quaternary ammonium salt phase transfer catalyst is adopted, the ee value of the obtained product can reach 99.5% or above without chiral resolution, the yield is high (even can reach 77.6%), no highly toxic cyanide participates in the preparation process, and the method is safe and environmentally friendly.

The invention belongs to the technical field of catalyst preparation, and particularly relates to a preparation method of a high-dispersion platinum group noble metal-based catalyst, which comprises the following steps: preparing a porous rod-like cobaltosic oxide carrier material, cleaning with deionized water, drying, and roasting for 4-8 hours; dissolving chloroplatinic acid or platinum chloride in deionized water to form a noble metal solution; soaking the treated cobaltosic oxide carrier in a noble metal solution, taking out the carrier from the solution after soaking is completed, filtering, cleaning, drying, and roasting for 4-6 hours in an inert gas atmosphere; and keeping the temperature and reducing for 2-4 hours in a hydrogen atmosphere. When the porous rodlike cobaltosic oxide carrier material is prepared, firstly, a cobalt chloride solution is poured into the lower part of the double-layer cavity for stirring, a urea solution drips into the cavity through a spray head in the stirring process, a stirring barrel is turned over after stirring is completed, the stirred solution flows out and is filtered, the cobalt chloride solution and the urea solution are continuously added into the double-layer cavity for stirring and mixing, and the porous rodlike cobaltosic oxide carrier material is prepared. Therefore, the porous rod-like cobalt oxide solvent material is efficiently prepared.

The invention belongs to the technical field of chemical catalysts, and particularly discloses a high-humidity-tolerance Pt / SSZ-13 molecular sieve catalyst and a preparation method and application thereof.The preparation method comprises the following steps that S1, a platinum metal precursor solution is prepared, specifically, platinum particles are added into a solvent according to a certain proportion, and the platinum metal precursor solution is obtained through dispersion and dissolution; s2, dipping and loading: dipping an SSZ-13 molecular sieve carrier into the platinum metal precursor solution obtained in S1 by adopting a dipping method, and uniformly stirring; s3, drying: drying at the temperature of 60-120 DEG C for 3-12 hours; s4, roasting: roasting for 1-10 hours at the temperature of 600-800 DEG C in an air atmosphere; and S5, reduction: reducing at 100-300 DEG C in a hydrogen atmosphere for 1-3 hours to obtain the Pt / SSZ-13 molecular sieve catalyst. According to the high-humidity-tolerance Pt / SSZ-13 molecular sieve catalyst as well as the preparation method and the application thereof, the Pt / SSZ-13 catalyst is obtained by utilizing a small-hole molecular sieve carrier and optimizing Pt loading and a preparation process, the high-humidity-tolerance and stability are realized, and the problem that an existing catalyst is insufficient in activity under the conditions of room temperature and high humidity is solved.

The invention discloses a perovskite / crystalline silicon laminated solar cell, a preparation method thereof and a photovoltaic module. The perovskite / crystalline silicon laminated solar cell provided by the invention comprises a perovskite top cell, a crystalline silicon bottom cell and a composite layer used for connecting the perovskite top cell and the crystalline silicon bottom cell, the perovskite top cell comprises a composite hole transport layer, the composite hole transport layer comprises a first hole transport layer and a second hole transport layer, and the first hole transport layer is in contact with the composite layer; the first hole transport layer is obtained by sputtering a nickel oxide target material by introducing H2 in an oxygen-free sputtering atmosphere, and the second hole transport layer is obtained by sputtering the nickel oxide target material in a hydrogen-free atmosphere. According to the perovskite / crystalline silicon laminated solar cell provided by the invention, the composite hole transport layer can realize better contact matching with the middle composite layer, better charge extraction and collection are carried out on the perovskite light absorption layer, and meanwhile, the perovskite / crystalline silicon laminated solar cell has better conductivity.

The invention discloses a catalyst for catalyzing diethylene glycol to prepare N-methylmorpholine and a preparation method of the catalyst, and belongs to the field of catalysts. The catalyst for catalyzing diethylene glycol to prepare N-methylmorpholine is composed of uniformly distributed Ni and Cu particles and a NiCuXY oxide solid solution carrier, and the catalyst is prepared by roasting and reducing a NiCuXY mixed hydroxide precursor in a hydrogen atmosphere; wherein X and Y are selected from any one of Al, Zr, Ce, Cr, Ti, Mo and Mg; and X and Y are different. According to the invention, the interface synergistic effect of a NiCu metal active center and a NiCuXY solid solution carrier is utilized; the catalyst disclosed by the invention is simple in preparation method, relatively low in cost, mild in reaction condition, low in energy consumption and beneficial to being applied to an industrial production process.

The invention relates to the technical field of catalysts, and particularly discloses a Cu-based catalyst for preparing 1, 2-pentanediol and a preparation process of the 1, 2-pentanediol. The Cu-based catalyst used for preparing 1, 2-pentanediol comprises 6-72% of a copper salt, 20-70% of a carrier, 4-12% of a transition metal oxide and 4-12% of a polymeric nitrogen-containing organic ligand, and the polymeric nitrogen-containing organic ligand is polypyrrole or polyaniline. The preparation process of the 1, 2-pentanediol comprises the following steps: mixing furfural, isopropanol and a Cu-based catalyst for preparing the 1, 2-pentanediol, adding the mixture into a high-pressure reaction kettle, and reacting for 10-14 hours in a hydrogen atmosphere of 2.8-3.2 MPa and at the temperature of 145-155 DEG C under continuous stirring to obtain the 1, 2-pentanediol. According to the Cu-based catalyst, the combination effect between the carrier and Cu can be enhanced, so that active Cu loaded on the carrier is more stable in the reaction process, and the catalytic performance of the Cu-based catalyst is improved.

The invention belongs to the technical field of fluorine chemical industry, and relates to preparation and application of a hydrodechlorination catalyst, a preparation method comprises the following steps: dipping a palladium source and a copper source on an activated carbon carrier, drying, and sequentially carrying out heating pretreatment in an inert atmosphere, reduction treatment in a hydrogen atmosphere and passivation treatment in an air atmosphere; in the obtained catalyst, the loading capacity of palladium on the activated carbon carrier is 0.5-0.1 wt%, and the loading capacity of copper on the activated carbon carrier is 5-0.1 wt%. Compared with the prior art, the preparation method has the advantages of low metal loading capacity, low reaction temperature, controllable product selectivity and the like, and the granular active carbon is adopted, so that the influence of active carbon extrusion molding and molding auxiliaries on preparation and performance of the catalyst can be avoided. Meanwhile, the catalyst can be used for the hydrodechlorination reaction of CFC-113, the problems of fast deactivation, poor stability and high use cost of the conventional catalyst can be solved, and an effective way is provided for converting fluorochloroalkane into fluorine-containing olefin.

The invention discloses a production method of HMDA (4, 4 '-MDA), which comprises a process of pretreating a catalyst before a catalytic hydrogenation reaction of 4, 4'-MDA, the pretreatment method of the catalyst comprises the following steps: mixing the catalyst, a solvent and a heavy component-reaction regulator, treating for a period of time in a high-temperature hydrogen atmosphere, filtering out the catalyst after the treatment is finished, and carrying out a subsequent catalytic hydrogenation reaction; the heavy component, namely the trans regulator, is cis-1, 4-di (aminomethyl) cyclohexane; preferably, the addition amount of the heavy component, namely the anti-reaction regulator, is 0.1-15 wt% of the mass of the catalyst. The yield of the H12MDA exceeds 95%, the trans-trans isomer content is 13-15%, no heavy components are generated, the unit consumption of the raw materials is greatly reduced, and the catalyst is not inactivated after being used for 60 batches.

The invention relates to a polysaccharide coated-hydrogen pre-sintered dispersed graphene copper composite material and a preparation method thereof, and the preparation method comprises the following steps: mixing first copper powder with a coating solution, and removing a solvent to obtain coated copper powder; sintering the coated copper powder in a hydrogen atmosphere for the first time to obtain graphene coated copper powder; second copper powder and the graphene-coated copper powder are mixed, and the graphene-copper composite material is obtained through second sintering and forming; the solute of the coating solution comprises polysaccharide and an organic auxiliary agent, and the number of carbon atoms of the polysaccharide is greater than or equal to 10. According to the preparation method, through molecular-level coating of the polysaccharide and the organic additive, the coating layer is converted into a few-layer graphene or high-quality carbon layer which is uniformly attached to the surface of the copper powder in situ during first sintering, so that the high-quality graphene copper composite material is obtained.

The invention discloses a preparation method of nano tungsten-nickel-iron composite powder, which comprises the following steps: 1, dissolving ammonium metatungstate, nickel chloride hexahydrate and ferric chloride hexahydrate in water, and stirring to obtain a solution; step 2, atomizing the solution and spraying the atomized solution into liquid nitrogen for pre-freezing to obtain frozen particles; 3, freeze-drying the frozen particles to obtain precursor composite powder; and 4, the precursor composite powder is subjected to roasting and reduction in the hydrogen atmosphere in sequence, and the nano tungsten-nickel-iron composite powder is obtained. According to the preparation method, frozen particles containing tungsten, nickel and iron are obtained through pre-freezing, then solid ice of the frozen particles is directly sublimated into gas to be separated through a freeze-drying process, nanoscale precursor composite powder is obtained, and the nano tungsten-nickel-iron composite powder is prepared through roasting and reduction in the hydrogen atmosphere. The method is suitable for the technical field of powder preparation engineering.

The invention provides a method for synthesizing diol from glucose, which comprises the following steps: adding glucose, a catalyst and deionized water into a reaction kettle, and carrying out heating catalytic reaction in a hydrogen atmosphere to obtain diol, the main product of which is butanediol; wherein the catalyst is a Pd-WO3 composite nano catalyst loaded by a carrier. The catalyst can be used for preparing diol, the novel catalyst is formed by combining the carrier and the specific composite nano-catalyst, the combination can selectively catalyze glucose to be converted into 1, 2-butanediol under mild conditions, and compared with an existing metal catalyst, the catalyst has higher catalytic efficiency and conversion rate; meanwhile, the catalyst is stable in activity and longer in service life, so that the production cost is reduced, and the production efficiency is improved; in addition, the preparation process of the catalyst is simple, the catalyst can keep excellent catalytic activity in the recycling process, and compared with an existing catalyst preparation process, the preparation method has higher production efficiency and economic benefits.