3902 results about "Nitric acid" patented technology

The invention belongs to the technical field of rare earth functional materials, and particularly relates to a rare earth aluminate low-temperature magnetic refrigeration material and a preparation method and application thereof.The preparation method comprises the following steps that 1, rare earth metal nitrate and aluminum nitrate are added into water to be mixed, and a mixed solution is prepared; adding ammonia water into the mixed solution to prepare a precipitate; (2) carrying out annealing treatment on the precipitate to prepare a metal oxide; and (3) calcining the metal oxide to obtain the rare earth aluminate low-temperature magnetic refrigeration material. The rare earth aluminate which has the characteristics of stable structure, low preparation cost, strong mechanical property, high magnetic density and the like and is prepared by adopting a coprecipitation method and combining a high-temperature sintering technology has more excellent magnetocaloric properties in a low-temperature region.

The invention relates to a carbon quantum dot for strengthening and promoting growth of microalgae and application thereof. In the process of preparing the carbon quantum dots by a conventional hydrothermal method, a precursor mixture is subjected to acidification modification in advance, the pH value is adjusted to 2 by using nitric acid, and then a hydrothermal reaction is performed, so that the prepared carbon quantum dots have the capability of promoting the growth of microalgae. However, if other acids are adopted or pH adjustment is not in place, the effect cannot be achieved, and even the inhibition effect can be achieved. The obtained product is good in effect and stable in performance, no special reaction device needs to be additionally arranged in the acidification modification process, and the method has the advantages that operation is easy and convenient, raw materials are easy to obtain, and the process can be quantified; the method is simple and convenient in process operation, has universality and is easy for industrial production.

The invention relates to the technical field of preparation of catalysts, in particular to a catalyst for in-situ capture of carbon dioxide, a preparation method of the catalyst and application of the catalyst to preparation of methanol from methane, and the preparation method comprises the following steps: S1, mixing and stirring Bi (NO3) 3.5 H2O, dilute nitric acid and an adsorption modifier; s2, filtering to obtain a white precipitate, drying, slowly heating to 450 DEG C in a muffle furnace, and keeping the temperature for 20-30 minutes to obtain a faint yellow solid; s3, dispersing in a modified dissolving solution, sealing the reactor, and purging with argon for 10-15 minutes; and S4, injecting CH4, reacting for 2 hours under the irradiation of a xenon lamp, washing a solid obtained by suction filtration with deionized water, and drying at 60 DEG C for 10-12 hours to obtain the high-performance catalyst. The invention aims at the field of preparation of high-value chemicals from photocatalytic methane, solves the problem of generation of carbon dioxide by peroxidation of methane, and captures the peroxidation product carbon dioxide through the cooperation of the adsorption modifier and the modified dissolving solution to inhibit peroxidation of methane.

The invention discloses a method for preparing a bismuth ferrite composite catalytic material by using red mud as well as a product and application of the bismuth ferrite composite catalytic material. The method comprises the following steps: mixing chlorine salt and red mud, uniformly stirring, adding a hydrochloric acid solution, uniformly stirring, roasting, recovering flue gas generated in the roasting process, and obtaining roasting residues and roasting dust generated by recovering the flue gas after roasting is finished; and mixing the roasted dust and bismuth nitrate, uniformly stirring, adding the calcined residue, uniformly grinding, adding water, stirring, drying the material, and calcining to obtain the bismuth ferrite composite catalytic material. The preparation process is simple, the red mud is used as a main raw material, and full-amount resource utilization of the red mud can be achieved. The prepared composite catalytic material can be used for efficiently purifying landfill leachate, and COD, ammonia nitrogen, total phosphorus and heavy metal pollution are efficiently removed through a photocatalysis mechanism.

The invention discloses a method for synthesizing GaOOH and beta-Ga2O3 materials with relatively good crystal quality and relatively uniform phase by taking gallium nitrate as a gallium source through a hydrothermal method and high-temperature calcination treatment, and characterizing the GaOOH and beta-Ga2O3 materials. The hydrothermal method adopted by the method has the advantages of simplicity in operation, low cost and the like, and has great advantages in the aspect of synthesizing gallium oxide. And compared with the traditional methods such as CVD (Chemical Vapor Deposition) and the like, which need to introduce noble metal elements as catalysts, easily cause reduction of material crystal quality and introduce unnecessary impurity elements, the method disclosed by the invention can be used for synthesizing the gallium oxide material with relatively good crystal quality and relatively uniform phase by combining a hydrothermal method and high-temperature calcination treatment. GaOOH powder is synthesized by adding an anionic surfactant sodium dodecyl benzene sulfonate (SDBS) solution with different concentrations, and then the GaOOH powder is calcined at the high temperature of 900 DEG C to obtain beta-Ga2O3 materials with different sizes.

A method of synthesis of single crystal nickel-rich cathode materials can include preparing a precursor solution by dissolving lithium nitrate, nickel nitrate, manganese nitrate, and cobalt nitrate in water, aerosolizing the solution of a) in a stream of air using an ultrasonic sprayer, preheating the resulting droplets, premixing the droplets with methane, decomposing the droplets by passing through a co-flow burner, depositing solid particles on a filter, and calcinating the solid particles in a furnace in oxygen to produce a single crystal cathode material.

The invention relates to the technical field of guanidine nitrate preparation, in particular to a method for preparing guanidine nitrate by a continuous dynamic tubular reaction process, which comprises the following steps: uniformly mixing dicyandiamide, target ammonium nitrate and target ammonium carbonate according to a mass ratio of 1: (1-3): (1-0.5); conveying the uniformly mixed material to a feeding section in a dynamic tubular reactor through a first conveying screw rod for mixing treatment, wherein the dynamic tubular reactor further comprises a heating section, a reaction section and a cooling section; sequentially conveying the target mixed material to a heating section for heating melting treatment, a reaction section for synthesis reaction treatment and a cooling section for cooling forming treatment through a second conveying screw rod to obtain an initial product; conveying the initial product into a cooling and crushing device for cooling and slicing to obtain a target guanidine nitrate product. According to the method disclosed by the invention, the mass and heat transfer efficiency can be improved, the online quantity and liquid holdup of the material are reduced, meanwhile, the raw material ratio and the reaction path are optimized, and the safety and the product purity are improved.

The invention relates to the technical field of metal surface treatment, and discloses a titanium felt surface pickling process which is characterized by comprising the following steps: step 1, pretreating a titanium felt; step 2, preparing a pickling solution, wherein the pickling solution comprises 3-5% (by volume) of hydrofluoric acid, 15-20% (by volume) of nitric acid, 0.5-1% (by mass) of a corrosion inhibitor and the balance of deionized water; 3, acid pickling is conducted, specifically, the pretreated titanium felt is hung in an acid pickling tank through a clamp, it is ensured that the titanium felt is completely immersed in an acid pickling solution, a stirring device is started, the speed is controlled to be 100-200 r / min, the temperature is controlled to be 30-40 DEG C, and acid pickling is conducted for 5-15 min; and step 4, cleaning. The titanium felt surface pickling process has the advantages of being efficient in cleaning, low in damage, environmentally friendly and safe.

The present invention generally relates to a method for synthesizing NiO / ZnO nanoparticles using solution combustion synthesis. The method comprising: dissolving 10 grams of Zinc nitrate hexahydrate (Zn(NO3)2·6H2O) and 10 grams of Nickel(II) nitrate hexahydrate (Ni(NO3)2·6H2O) in 30 ml of double-distilled water to obtain a solution; adding at least one fuel selected from a group consisting of glucose, urea, and combinations thereof to the solution; stirring the solution for one hour to achieve homogeneity and transferring the homogeneous solution into a Pyrex dish; placing the dish inside a preheated muffle furnace at a temperature range of 440° C. to 460° C. and allowing the solution to boil, froth, and undergo exothermic combustion thereby retrieving the resulting fine nanoparticle powder upon completion of the reaction within 20 minutes; and cooling the synthesized powder to room temperature and grinding the powder to achieve a fine, uniform consistency, thereby forming NiO / ZnO nanoparticles.

The invention belongs to the technical field of denitration catalyst preparation, and discloses a meerscham-TiO2 composite carrier loaded manganese cerium medium and low temperature denitration catalyst and a preparation method and application thereof, the preparation method comprises the following steps: (1) mixing meerschaum and nitric acid, then heating and stirring for reaction, then carrying out suction filtration and washing, and drying to obtain a meerschaum-TiO2 composite carrier loaded manganese cerium medium and low temperature denitration catalyst; after the treated sepiolite is drained, drying and screening are conducted, and nitric acid acidified sepiolite is obtained; and (2) mixing the meerschaum acidified by nitric acid and TiO2, then adding the manganese source precursor solution into the acidified meerscham-TiO2, then dipping and stirring, dropwise adding a potassium permanganate solution into the solution, then adding a cerium nitrate solution, stirring and then carrying out suction filtration, drying, grinding and screening the obtained filter cake, and then calcining to obtain the catalyst. According to the invention, the acidified sepiolite and TiO2 are compounded, so that complementary advantages of the two carrier materials are realized, and the obtained catalyst not only has good denitration efficiency, but also can significantly reduce the production cost.

The invention relates to the technical field of conductive materials, in particular to a high-concentration dispersion system and a preparation method thereof. The high-concentration dispersion system comprises a conductive agent, a dispersing agent, a solvent and a viscosity reduction auxiliary agent, the conductive agent is modified carbon nanotubes, the dispersing agent is modified polyvinylpyrrolidone, the solvent is N-methyl pyrrolidone or deionized water, and the viscosity reduction auxiliary agent is piperazine anhydrous; wherein the modified carbon nano tube is obtained by mixing and heating a carbon nano tube and a mixed acid solution of nitric acid and sulfuric acid, then cooling, filtering, washing, drying, then dispersing in 75% ethanol, and finally adding 3-[3-carboxyl allylamido] propyltriethoxysilane for modification; the modified polyvinylpyrrolidone is obtained by heating polyvinylpyrrolidone at 310-330 DEG C and then oxidizing the polyvinylpyrrolidone. The conductive agent content of the high-concentration dispersion system is high, the conductive agent accounts for 15%-20% of the high-concentration dispersion system by mass, and the high-concentration dispersion system is low in viscosity, high in dispersity and good in conductivity.

The invention belongs to the technical field of heating bodies, and particularly relates to a method for preparing a sheet-shaped heating body. The preparation method comprises the following steps: stirring and dissolving lanthanum nitrate, strontium nitrate, manganese nitrate hexahydrate and a solvent to obtain a metal salt solution; preparing the metal salt solution into a precursor, wherein the precursor is a precursor solution or precursor sol; and carrying out tape casting and drying on the precursor to obtain a biscuit sheet, and carrying out glue removal treatment and sintering on the biscuit sheet to obtain the sheet-shaped heating body. According to the preparation method, a precursor system is optimized, the dispersion stability of the precursor is improved, casting, drying and sintering processes are matched, the problem of powder agglomeration is solved, the defects of green bodies are reduced, the drying shrinkage rate of green body pieces in the preparation process is reduced, the surface roughness is reduced, the stability and heat output uniformity of a heating body are improved, and the compactness is improved.

The invention relates to the technical field of composite catalyst materials, in particular to a ferrocobalt bimetal hydroxide / BCN composite material and a preparation method and application thereof.The preparation method comprises the steps that cobalt nitrate and ferric nitrate are used for preparing a metal salt solution, sodium carbonate and sodium hydroxide are used for preparing a precipitant solution, a B-doped carbon nitride BCN material is added into the metal salt solution to form a uniform suspension, and the suspension is dried to obtain the ferrocobalt bimetal hydroxide / BCN composite material; dropwise adding the precipitant solution into the suspension to obtain a precursor solution, performing hydrothermal reaction on the precursor solution, and performing centrifugal impurity removal and drying to construct a heterostructure between layered double hydroxide and BCN in situ to obtain the Co-Fe LDH-coated BCN composite material. Through boron doping and heterostructure construction, the charge separation capacity of graphite carbon nitride is enhanced, the electron migration efficiency is improved through a heterointerface structure, the metal ion release amount and the cycle stability are controlled, and the catalytic performance is remarkably improved.

The invention discloses a neodymium-zirconium co-substituted M-type strontium ferrite wave-absorbing material and a preparation method thereof, the chemical formula of the neodymium-zirconium co-substituted M-type strontium ferrite wave-absorbing material is Sr1-xNdxZr0. 2Fe11.8 O19, and x is more than or equal to 0.1 and less than or equal to 0.4. The method comprises the following steps: (1) mixing strontium nitrate, ferric nitrate nonahydrate, neodymium nitrate hexahydrate, zirconium nitrate pentahydrate, citric acid monohydrate and deionized water, stirring and dissolving to obtain sol; (2) adjusting the pH value of the sol to 6.5-7.5, and then heating to carry out sol-gel reaction to obtain wet gel; (3) drying and grinding the wet gel to obtain precursor powder; and (4) performing heat treatment on the precursor powder in a box-type furnace, cooling and grinding to obtain the neodymium-zirconium co-substituted M-type strontium ferrite wave-absorbing material. According to the material, effective wave-absorbing frequency band broadening is achieved, the matching thickness corresponding to the effective wave-absorbing bandwidth is as thin as 0.55-0.7 mm, and meanwhile, the performance requirements of thinness, width and strength in the field of electromagnetic compatibility are met.

The invention relates to the technical field of metal material sample preparation, in particular to a preparation method for extracting carbon replica of steel for a high-carbon wire rod. The method specifically comprises the following steps: S1, preparing a sample; s2, immersing the sample into a nitric acid alcohol solution; s3, placing the sample in a sample chamber of a high-vacuum coating instrument, evaporating a carbon film with the thickness of 10-20 nm on the surface of the sample, and taking out the sample after vacuum is relieved; s4, performing electrolytic film removal by adopting an electrolytic polishing corrosion instrument; s5, after the carbon film falls off, the nitric acid alcohol on the carbon film is cleaned until the absolute ethyl alcohol in the weighing bottle is colorless; s6, the carbon film is transferred into deionized water, after the carbon film is fully unfolded, the carbon film is fished up through a transmission electron microscope and a copper net and placed on filter paper, and the carbon film is tightly attached to the copper net; and S7, baking the carbon film sample adhered to the copper mesh for 30-60 seconds, and placing the dried sample under an electron microscope for observation to complete the preparation of the steel extraction carbon replica sample for the high-carbon wire rod. The method has the advantages of high demolding speed, complete and firm carbon film form, simple configuration and low cost.

The invention discloses a high-strength hoop and a processing method thereof in the technical field of mechanical connection fasteners. The high-strength hoop comprises the following raw materials: modified carbon fibers, a modified epoxy resin matrix, chopped glass fibers, an antioxidant and an aluminate coupling agent. Cleaning the modified carbon fibers with acetone to remove oil stains, oxidizing the modified carbon fibers with concentrated nitric acid at 80-85 DEG C to generate polar functional groups containing hydroxyl and carboxyl, washing the modified carbon fibers with water until the modified carbon fibers are neutral, drying the modified carbon fibers, immersing the modified carbon fibers into an absolute ethyl alcohol solution of an aluminate coupling agent for ultrasonic dispersion, and curing the modified carbon fibers at 100-105 DEG C; the modified epoxy resin matrix is prepared by heating and melting epoxy resin, adding nano montmorillonite, stirring and dispersing, adding polyamide, an accelerant and a flexibilizer, and carrying out vacuum defoaming at 100-105 DEG C. The hoop has the advantages of high strength, weather resistance and the like by modifying and enhancing interface bonding and matrix toughness, and is suitable for connection under complex working conditions.

The invention relates to a detection method and application of a bainite steel structure and / or grain boundary for nuclear power equipment, and relates to the technical field of new material detection. According to the detection method, the problem that the structure and the grain boundary of bainite steel for nuclear power equipment are difficult to display can be solved, a major breakthrough of a grain size detection technology is achieved, the clear and complete grain boundary can be accurately presented, and scientific evaluation of the grain size through a comparison method, a cut point method, an area method and the like according to standard requirements is further supported. When the detection method is used for evaluating the grain size, the results are highly consistent, the repeatability is good, and the problems of subjective experience dependence and measurement errors caused by blurred grain boundary display in a traditional nitric acid and alcohol corrosion method are effectively avoided.

The invention discloses a synthesis method of a hydrazine dicarboxylate modified cerium dioxide abrasive, and belongs to the technical field of precise polishing materials. The method comprises the following steps: taking cerous nitrate as a raw material, and preparing a cerous carbonate precursor through an ammonium carbonate precipitation reaction; and grinding and calcining the obtained precursor and hydrazine dicarboxylate to obtain the CeO2 grinding material with the surface rich in oxygen vacancies. And Ce < 4 + > can be partially reduced into Ce < 3 + > by reducing fragments generated by decomposition of the hydrazine dicarboxylate in the calcining process, so that an oxygen vacancy structure is formed through induction, and the chemical activity and the reaction rate of the abrasive are improved. The obtained grinding material shows excellent performance in chemical mechanical polishing (CMP) of K9 glass, the material removal rate (MRR) is increased by about 3.6 times compared with that of unmodified CeO2, the surface roughness (Ra) is reduced to about 0.16 nm or below, and grinding material particles are good in dispersity and less in agglomeration. The used hydrazine dicarboxylate is stable, low in toxicity and mild in reaction, and the particle size can be prevented from excessively growing while the high oxygen vacancy concentration is kept.

The invention relates to the technical field of new material detection, in particular to a copper foil coating content detection method. The method comprises the following steps: preparing a plurality of mixed standard solutions; the mixed standard solution comprises copper ions and at least one to-be-detected element ion; in the plurality of mixed standard solutions, the copper ion concentrations are the same and are first preset concentration values; measuring a plurality of mixed standard solutions, and establishing a standard curve between a theoretical value and a measured value of the ion concentration of each to-be-measured element; dissolving a plating layer on the surface of the to-be-detected copper foil by using nitric acid, and filtering to obtain a to-be-detected sample solution; adding copper salt into the to-be-detected sample solution to obtain a to-be-detected analysis solution; measuring the to-be-measured analysis solution to obtain the measurement concentration of each to-be-measured element ion; according to the measured concentration of each to-be-measured element ion and the corresponding standard curve, the corrected content of each to-be-measured element ion is obtained. The problem that an existing copper foil coating content detection method is low in detection accuracy is solved.

The invention relates to the technical field of pendimethalin wastewater treatment, in particular to a pendimethalin wastewater treatment method which comprises the following steps: step 1, adding ferrous oxide or ferrous hydroxide into wastewater, and adjusting the pH value of the wastewater to be neutral; 2, adjusting the pH value of the primary filtrate to 2-5 by using an inorganic acid, and adding an iron-carbon mixture with the mass ratio of 1: (0.5-2) to carry out an oxidation-reduction reaction; and step 3, introducing the secondary filtrate into 2-5 reaction kettles which are connected in series, and adding hydrogen peroxide for 1-3 times according to the mass ratio of hydrogen peroxide to COD (Chemical Oxygen Demand) of (15-25): 1. According to the pendimethalin wastewater treatment method provided by the invention, the iron-carbon mixture generates a primary battery effect in the solution, nitrate radicals can be quickly reduced into nitrogen oxides or ammonia gas, the nitrate radicals are efficiently and quickly treated, and meanwhile, iron ions and ferrous ions can finally generate corresponding hydroxides to be separated out.

The present invention discloses a method for preparing highly dispersible submicron spherical palladium powder. The method comprises the following steps: first, weighing solid palladium nitrate and dissolving it in dilute nitric acid to prepare a dilute palladium nitrate solution; then dissolving a reducing agent in deionized water to obtain a reducing solution; then weighing a dispersant and an additive and dissolving them in deionized water to obtain a mixed base solution; and then mixing the three to obtain a reaction slurry containing palladium powder. The mixture is then filtered, washed, and dried to obtain submicron spherical palladium powder particles. The present invention adopts a liquid phase reduction method to reduce the palladium nitrate solution with ascorbic acid or hydrazine hydrate as a reducing agent to prepare the submicron spherical palladium powder. An organic polymer dispersant and a small molecule alcohol additive are simultaneously added to the base solution in a symmetrical manner. While ensuring the yield of palladium powder, the particle growth process and dispersibility are well controlled. The prepared palladium powder particles are spherical and highly dispersed, with a particle size of 100 to 600 nm.

The invention discloses a La2O3-ZnO-NiO / ZrO2 oxygen carrier as well as a preparation method and application thereof, and belongs to the technical field of ammonia decomposition. According to the technical scheme, the method comprises the following steps: 1) synthesis of a ZrO2 carrier: adding NH3.H2O into a zirconyl nitrate solution to induce precipitation; 2) preparation of La2O3 / ZrO2: adding lanthanum nitrate hexahydrate and urea to obtain a precipitate, drying the precipitate, and finally calcining the precipitate; 3) preparation of La2O3-ZnO / ZrO2: adding zinc nitrate hexahydrate and urea, standing to obtain a precipitate, drying and calcining; and 4) preparation of La2O3-ZnO-NiO / ZrO2: adding NH3.H2O, then adding nickel acetate and thiourea, reacting, drying, and calcining twice to obtain the target product. Lattice oxygen in the oxygen carrier is used for catalytic oxidation of ammonia decomposition, the oxygen carrier can be recycled for multiple times, and the method is suitable for industrial application in the future.

The invention relates to the technical field of metal material hot working, and discloses a hot-rolled coiled plate production process which comprises the following steps: preparing a reaction type protective agent, the high-temperature-resistant coating is prepared from the following raw materials in parts by weight: 20 to 40 parts of tetraethoxysilane, 5 to 15 parts of triethyl phosphate, 1 to 5 parts of triethyl borate, 0.5 to 2.0 parts of cerous nitrate (III) hexahydrate, 0.1 to 1.0 part of lithium acetate and 0.01 to 0.05 part of vanadyl acetylacetonate (IV). Coating the surface of a hot-rolled plate blank with the protective agent; the coated plate blank is heated in a heating furnace, so that the protective agent forms a molten-state protective layer in situ; carrying out hot rolling on the plate blank with the molten protective layer; and cooling and coiling the hot-rolled steel strip. In the whole heating and hot rolling process, the molten protective layer isolates the contact between the steel and the oxidizing atmosphere, so that the generation of oxide scales is fundamentally inhibited, the production process is simplified, and the metal yield is increased.

The invention discloses a catalyst for catalyzing ethane to prepare ethylene or an oxygen-containing compound as well as a preparation method and application of the catalyst, and belongs to the field of catalysts. On the basis of ERB-1 and MCM-22, a large number of hydroxyl structures are formed through post-treatment of nitric acid or ammonium nitrate; a titanium source and molecular sieve silicon hydroxyl are subjected to a dehydrohalogenation reaction in a titanium halide gas form to form a Ti-O-Si bond, so that titanium successfully enters a molecular sieve framework and is uniformly distributed. Au or Pd is anchored by a framework Ti, Au or Pd is loaded by using a deposition-precipitation method, and the introduced Ti species can provide a better environment for further dispersing Au or Pd by changing isoelectric points on the surface of a molecular sieve carrier, so that the size of Au or Pd nanoparticles is controlled; secondly, due to the high specific surface area of the MWW molecular sieve, the gold precursor can be effectively dispersed, and agglomeration is inhibited; compared with an MWW molecular sieve of pure Si, Au or Pd nanoparticles can be dispersed and anchored by introducing a framework Ti, so that an Au and Pd-based catalyst which is about 2nm in size and good in dispersion is prepared.

The invention relates to the technical field of synthesis of a polymerization inhibitor DNBP, in particular to an efficient production method of the polymerization inhibitor DNBP, which comprises the following steps: step 1, material preparation: selecting corresponding raw materials, weighing and classifying the raw materials, and dividing the raw materials into three main materials, auxiliary materials and additives, the auxiliary material comprises a sulfonic acid type ion exchange resin catalyst, the additive is an ethanol-water mixed solvent, and during weighing, weighing and proportioning are performed according to the molar ratio of nitric acid to o-tert-butylphenol being 2.15: 1 and the mass ratio of o-tert-butylphenol to carbon tetrachloride being 0.15: 1; according to the method, a gradient temperature control strategy is adopted, and a multi-stage microchannel reactor is combined, so that efficient mass and heat transfer of nitration reaction is realized, deep nitration side reaction is inhibited, the content of dinitro isomer impurities is greatly reduced, meanwhile, the total residence time can be accurately controlled, the explosion risk caused by local overheating in a traditional process is avoided, and the method is suitable for industrial production. The reaction selectivity and the safety are obviously improved.

The preparation method comprises the following steps: S1, uniformly mixing aluminum hydroxide dry glue powder, silica sol and an extrusion aid, then adding deionized water and nitric acid for mixing and kneading, and after caragana microphylla is formed, drying and roasting to obtain an aluminum oxide-silicon oxide composite carrier; s2, putting the carrier into a modification solution, and performing modification treatment in a high-pressure reaction kettle to obtain a modified aluminum oxide-silicon oxide composite carrier; and S3, preparing a precursor containing metals Mo, Co and Re into an impregnation liquid, adding L-asparaginic acid into the impregnation liquid, impregnating the modified alumina-silicon oxide composite carrier in the impregnation liquid, drying, and roasting to obtain the catalyst. The catalyst prepared by the method has high hydrodenitrogenation performance and metal capacity and long service life.

The invention discloses a preparation method and application of a high-nitrogen-doped ordered mesoporous carbon supported copper catalyst, and belongs to the technical field of catalyst preparation. The preparation method comprises the following steps: by taking cane sugar and a copper-nitrogen complex as raw materials, SBA-15 as a template agent and sulfuric acid as a catalyst, carrying out equivalent-volume impregnation, low-temperature heat treatment, 800-900 DEG C high-temperature carbonization and nitric acid / hydrofluoric acid demolding to prepare pyrrole nitrogen enriched or pyridine nitrogen enriched high-nitrogen doped ordered mesoporous carbon with a large specific surface area; the preparation method comprises the following steps: loading a copper species on high-nitrogen-doped ordered mesoporous carbon by adopting an equivalent-volume impregnation method, and reducing at 350-400 DEG C to prepare the high-nitrogen-doped ordered mesoporous carbon loaded copper catalyst. The prepared catalyst is high in nitrogen content, large in specific surface area, high in pyridine nitrogen or pyrrole nitrogen enrichment degree and uniform in copper particle dispersion and shows efficient catalytic performance in methanol oxidative carbonylation reaction, and the highest methanol conversion rate is 9.3%.

The invention relates to the technical field of molten salt, in particular to nitro binary molten salt and a preparation method thereof. The preparation method comprises the following steps: mixing sodium carbonate and a potassium hydroxide solution, and then adding a starch-based grafted crystal inhibitor to inhibit crystallization; adding a nitric acid aqueous solution in two stages, and introducing eutectic seed crystals to guide nucleation at the end of the first stage; crystal distribution is optimized through falling film evaporation and concentration and setting of partial reflux; and after spraying granulation, carrying out short-time melting reforming and controlled cooling in an inert atmosphere. According to the method, the composition uniformity and the structural stability of the molten salt are remarkably improved, so that the product has a melting point close to a theoretical eutectic point, low supercooling degree, high melting latent heat and excellent thermal cycling stability and corrosion resistance, and is suitable for an industrial heat storage system running for a long time.

The invention discloses a high-sulfur-tolerance SCR honeycomb denitration catalyst and a preparation method thereof, and belongs to the technical field of industrial catalysts.The preparation method comprises the steps that S1, anatase type TiO2 and NH4HCO3 are mixed for pulping, pre-drying and calcination are conducted after extrusion forming, and a green body is formed; s2, carrying out nitric acid treatment on the green body, dipping the green body in a mixed solution of copper nitrate hydrate and cerium nitrate hydrate, and carrying out vacuum dipping, microwave drying and two-stage calcination to obtain a desulfurization carrier; s3, depositing an ammonium metatungstate precursor on the surface of the desulfurization carrier through CVD, and calcining to form a WO3 transition layer; and S4, dipping the transition layer in an acid solution containing NH4VO3 and ammonium metatungstate, and calcining after ultrasonic treatment to obtain a finished product. According to the method, the pore structure of the carrier is optimized through chambering treatment, and the stability and denitration efficiency of the catalyst in high-sulfur flue gas are remarkably improved by combining a multistage sulfur-resistant mechanism that the desulfurization layer preferentially captures SO2, the WO3 transition layer obstructs sulfur penetration and the denitration layer is protected by active sites.

The invention discloses a perovskite type composite metal oxide oxygen carrier catalyst as well as a preparation method and application thereof, and belongs to the field of biomass chemical chain gasification / reforming. The oxygen carrier catalyst is of a La, Fe and Ni co-doped SrTiO3 perovskite structure, and active components Fe and Ni are embedded into a main body SrTiO3 perovskite crystal phase structure in an oxide or simple substance form; the method comprises the following steps: preparing an aqueous solution of lanthanum nitrate, strontium nitrate, nickel nitrate, ferric nitrate and citric acid, adding a mixed solution of tetrabutyl titanate and ethylene glycol into the aqueous solution, heating in a water bath, and stirring to form gel; drying and calcining the gel to obtain intermediate powder; and the intermediate powder is oxidized and reduced to form a high-temperature crystal structure under different atmospheres, and the perovskite type composite metal oxide oxygen carrier catalyst is obtained. The oxygen carrier catalyst provided by the invention has high tar conversion rate and stable cycle activity in the biomass chemical chain gasification / reforming process.