618 results about "Ammonium fluoride" patented technology

The invention discloses a silicon-carbon negative electrode material, porous carbon and a preparation method, the porous carbon is prepared by mixing ammonium fluoride and a pre-carbonized material to prepare a premix; and putting the premix in an inert atmosphere, and carrying out pre-activation, drying, carbonization, activation and crushing treatment to obtain the composite material. And uniformly depositing the nano silicon particles into the porous carbon skeleton through a mature CVD (Chemical Vapor Deposition) process to obtain the silicon-carbon composite material. Fluorine and nitrogen co-doping modification can increase the defect degree of a carbon skeleton, efficiently relieve mechanical stress accompanied by lithium storage volume expansion of the silicon negative electrode in a micro scale, provide abundant lithium ion transport and mass transfer channels and enhance the conductivity of porous carbon, and ammonium fluoride is used as a supplementary activator besides water vapor, so that the porosity of the porous carbon is further improved, and the conductivity of the porous carbon is improved. An effective space is provided for uniform deposition of silicon, the fluorine-containing carbon layer can induce formation of a high-stability SEI film rich in LiF on the surface of the nano silicon material, and the interface stability and coulombic efficiency of the silicon negative electrode are further improved.

The invention discloses a composite coated graphite negative electrode material, a preparation method thereof and a lithium ion solid-state battery, and belongs to the technical field of lithium ion solid-state batteries, the composite coated graphite negative electrode material comprises a graphite matrix and a composite coating layer, and the composite coating layer comprises an inner layer amorphous lithium chloride and an outer layer nanocrystalline LiF / Li3N composite phase. Mixing graphite, lithium chloride containing crystal water and ammonium fluoride to obtain a mixed material; placing the mixed material in a microwave reaction cavity, heating the mixed material to 600-700 DEG C at the microwave power of 800-1200 W in an H2 / Ar mixed atmosphere, and keeping the temperature for 20-60 minutes; and cooling the sintered mixed material, grinding, and sieving with a 100-300 mesh sieve to obtain the composite coated graphite negative electrode material with a coating layer thickness of 10-50 nm. The invention provides an innovative amorphous LiCl / nanocrystalline LiF-Li3N gradient coating layer design, the performance of the lithium ion battery is remarkably improved by optimizing an ion migration path, enhancing the interface stability and reducing the process cost, and a new engineering way is provided for realizing high magnification and long cycle performance of the sulfide all-solid-state battery.

The invention discloses a carbon-doped titanium dioxide nanotube-molybdenum disulfide energy-storage antibacterial material and a preparation method thereof. The preparation method comprises the following steps: carrying out primary anodic oxidation on a clean titanium foil in a mixed electrolyte of ethylene glycol, water and ammonium fluoride; after ultrasonic treatment is carried out in a hydrochloric acid solution for set time, secondary anodic oxidation is carried out, and the mixed electrolyte of the secondary anodic oxidation is the same as that of the primary anodic oxidation; annealing the titanium foil subjected to anodic oxidation twice in an argon atmosphere, putting an annealed sample into a mixed solution of sodium molybdate, a sulfur source and glucose, and carrying out hydrothermal treatment; and the titanium foil subjected to hydro-thermal treatment is cleaned and dried, and the carbon-doped titanium dioxide titanium foil with the surface covered with molybdenum disulfide is obtained. The MoS2-coated carbon-doped titanium dioxide nanotube (TNT-C-atMoS2) with high biocompatibility developed by the invention has a synergistic effect of charge antibiosis and chemical sterilization, so that the problem of intractable biological fouling of a titanium-based metal material in ocean engineering equipment is effectively solved.

The invention discloses a gas-sensitive material for monitoring an environment-friendly gas characteristic substance CO as well as a preparation method and application thereof, and relates to the technical field of gas-sensitive materials. The preparation method comprises the following steps: dissolving tin tetrachloride pentahydrate, sodium hydroxide and polyvinylpyrrolidone, adding ammonium fluoride, reacting at 155-165 DEG C, drying the product, and calcining at 295-305 DEG C to obtain SnO2 nanoparticles; the preparation method comprises the following steps: performing ultrasonic mixing on SnO2 deionized water dispersion liquid and MoS2 nanosheet ethylene glycol dispersion liquid, and then drying to obtain the MoS2 / SnO2 composite material with a mesoporous hollow nanotube structure, and the volume ratio of ethylene glycol to deionized water is (0.9-1.1): 1. The MoS2 / SnO2 gas sensitive material has the advantages of low density, high pore volume, large specific surface area, high structural stability and the like. And when applied to a CO resistive sensor, the catalyst has good CO selectivity, high sensitivity and good long-term stability.

The invention discloses an environment-friendly titanium alloy etching solution as well as a preparation method and an etching method thereof, and relates to the technical field of printed circuit board production. The environment-friendly titanium alloy etching solution comprises the following components in percentage by mass: 10-30% of ammonium fluoride, 5-15% of an oxidant, 0.1-1% of a wetting agent, 0.3-1.5% of a stabilizer, 2-10% of an accelerator and 0.5-3% of a lateral erosion inhibitor. The stabilizer is selected from at least one of Tween 20, Tween 40 and Tween 85; and the accelerator is selected from at least one of sodium methylene dinaphthalene sulfonate, sodium dibutyl naphthalene sulfonate and dodecyl benzoate. The environment-friendly titanium alloy etching solution disclosed by the invention can selectively and quickly etch titanium alloy without corroding a copper surface and other metals, so that etching factors are effectively increased, and the problem of lateral erosion of a fine circuit is solved. Meanwhile, ammonium fluoride is used as a main agent of the etching liquid instead of hydrofluoric acid, so that the environmental pollution can be effectively reduced.

The invention relates to an elementary substance / alloy-metal oxyhydroxide anchored noble metal single atom / cluster heterojunction catalyst. A preparation method comprises the following steps: 1) dissolving a metal salt A, urea and ammonium fluoride in deionized water to obtain a mixed solution B; 2) performing hydrothermal reaction on the mixed solution B and a carrier to obtain a primary sample 1; 3) performing high-temperature calcination on the primary sample 1 in a mixed atmosphere of hydrogen and argon to obtain a primary sample 2; and 4) putting the preliminary sample 2 into a noble metal compound C solution for vacuum impregnation, taking out the sample after impregnation, and drying to obtain the catalyst. According to the scheme, the metal salt A is used as a metal source of a simple substance / alloy, the metal salt A is subjected to hydro-thermal synthesis to form a metal hydroxide and then subjected to high-temperature calcination reduction, the metal salt A is calcined to form the simple substance / alloy, then the simple substance / alloy is soaked in the precious metal compound solution C to form a metal oxyhydroxide, and meanwhile precious metal single atoms / clusters are anchored; the prepared catalyst is high in activity, and the preparation method is simple.

The invention provides a method for preparing a spinel type catalyst rich in oxygen vacancies under the assistance of magnetization treatment and application of the spinel type catalyst. The synthesis method of the catalyst comprises the following steps: (1) preparing a precursor of the catalyst by adopting a hydrothermal method: putting a metal foam carrier into a mixed solution of metal salt ions such as ferric nitrate, manganous nitrate and cobalt nitrate, adding ammonium fluoride and urea, carrying out hydrothermal reaction, repeating the hydrothermal reaction for several times, and washing and drying to obtain the precursor; and (2) putting the catalyst precursor into a magnetization reactor, putting the magnetization reactor in the center of an alternating magnetic field coil, and carrying out magnetization treatment on the catalyst precursor in an air or oxygen atmosphere to obtain the spinel type catalyst rich in oxygen vacancies. The method is simple in process and low in cost, and the obtained product is uniform in morphology and good in repeatability and has high photo-thermal catalytic oxidation toluene performance. Through a clean, pollution-free and in-situ directional heating electromagnetic induction auxiliary technology, removal of oxygen atoms on the surface of the spinel catalyst is promoted, so that rich oxygen vacancies are introduced into cobalt-manganese spinel, the exchange effect between the catalyst and oxygen molecules is accelerated, and the reaction rate of catalytic oxidation of VOCs is promoted. When the intensity of simulated sunlight is 500 cm <-2 >, the concentration of toluene is 1000 ppm, the air speed is 45000 mL.gcat <-1 >. H <-1 >, the conversion rate of toluene reaches 86% or above, and high-efficiency oxidation of toluene can be realized under the driving of the simulated sunlight.

The invention belongs to the technical field of water electrolysis hydrogen production catalysts, and particularly relates to a preparation method and application of a bimetallic phosphide coupling layered double hydroxide electrocatalyst. The preparation method comprises the following steps: by taking a nickel source, an iron source, ammonium fluoride and urea as reactants, carrying out hydrothermal reaction to form a nickel-iron layered double hydroxide nano-catalyst precursor on a conductive substrate; and carrying out phosphating treatment on the nickel-iron layered double hydroxide nano-catalyst precursor by an electrodeposition method to obtain the bimetallic phosphide coupled layered double hydroxide electrocatalyst. Under the 1M potassium hydroxide solution test condition, the overpotential required by the catalyst is 89 mV when the current density in a linear scanning voltammetry curve is 10 mA cm <-2 >, and the catalyst is high in stability, simple in manufacturing process, energy-saving, suitable for industrial application and capable of being used for large-scale water electrolysis hydrogen production.

The invention discloses a selective etching solution for a titanium and / or copper metal layer of a circuit board and a preparation method of the selective etching solution, and the selective etching solution comprises the following components: 10-20% of persulfate, 4-8% of o-nitrobenzenesulfonate, 0.5-1% of phosphoric acid, 0.2-0.8% of 3-(aminomethyl) pyrazole, 0.3-1.5% of ammonium fluoride, 2-5% of cyclohexanediamine tetraacetic acid, 0.1-0.5% of cyclodextrine and the balance of water. The etching solution can selectively etch a titanium and / or copper metal layer, through selection and cooperation of etching solution components, etching is uniform and stable, taper angle and lateral etching control is good, metal wires are smooth, no metal residues exist, and a good etching solution is provided for the circuit board etching process.

The invention discloses a preparation method and application of octahedral cuprous oxide containing defects, and belongs to the technical field of material preparation. In order to solve the problems that in existing cuprous oxide preparation, a defect structure is difficult to accurately regulate and control, and the crystal form uniformity is insufficient, the method comprises the steps that a copper source solution, a glucose solution, a sodium citrate solution and an ammonium fluoride solution with specific concentrations are mixed according to the volume ratio, the pH is adjusted to 10.5-11, then a hydrothermal reaction is conducted, and a target product is obtained through centrifugation, filtration, washing and drying. The method comprises the following specific steps: mixing solutions, reacting in a high-pressure reaction kettle at 140-165 DEG C for 4-6 hours, and realizing octahedral crystal form construction and defect regulation and control by controlling the raw material ratio and reaction conditions. The preparation method is simple in process and high in controllability, and the prepared octahedral cuprous oxide containing defects can serve as a catalyst to be applied to the fields of catalytic decomposition of ammonium perchlorate and the like and has good industrial application prospects.

The invention discloses a catalyst for an n-butene isomerization reaction and a preparation method thereof, and belongs to the technical field of catalysts. The preparation method comprises the following steps: mixing a silicon source, an aluminum source, tetrapropylammonium hydroxide and water, adding boric acid, and crystallizing to obtain a seed crystal; the method comprises the following steps: mixing a silicon source, an aluminum source, pyridine and water, adding a seed crystal and ammonium fluoride, and crystallizing to obtain a core-shell type molecular sieve; adding the core-shell type molecular sieve into the bimetallic complex solution for dipping to obtain a metal-loaded type molecular sieve; adding the metal-loaded molecular sieve into a triethyl phosphine ethanol solution for treatment to obtain a phosphorus-modified molecular sieve; uniformly mixing the phosphorus-modified molecular sieve, pseudo-boehmite, sesbania powder and water, kneading, performing extrusion molding, drying and calcining to obtain the catalyst. The catalyst prepared by the invention is used for n-butene isomerization reaction, and has excellent catalytic activity and isobutene selectivity.

The invention relates to the field of fiber materials, and provides a low-dielectric constant glass fiber and a preparation method thereof, and the low-dielectric constant glass fiber comprises basalt glass fiber and a silicon oxyfluoride layer coating the surface of the basalt glass fiber. The basalt glass fiber is prepared by adopting a melting wire drawing method, the average diameter is 5.0-15.0 microns, and the volume ratio of a crystalline state to an amorphous state is controlled to be (5.0-15.0): (85.0-95.0). The thickness of the silicon oxyfluoride layer is 140-400 nm, and the silicon oxyfluoride layer is obtained through a sol-gel method and is formed by conducting dipping, ultrasonic treatment and purging on tetraethoxysilane and ammonium fluoride sol and then conducting heat treatment in an inert atmosphere. The preparation method comprises the steps of basalt raw material crushing, acid pickling, melting, wire drawing and gradient cooling, and the uniformity and stability of the fibers are ensured. The preparation conditions, impregnation parameters, purging pressure and heat treatment temperature of the modified sol are all optimized, so that uniform coating and stability enhancement are realized. The glass fiber provided by the invention has low dielectric constant and excellent heat resistance and hydrophobicity, and is suitable for the fields of high-frequency electronic substrates, aerospace and 5G communication.

The invention provides an ultra-pure thorium fluoride production process which comprises the following steps: preparing a nanoscale ThF4.xNH4F precursor through a gas-liquid-solid three-phase reaction, atomizing an ammonium fluoride solution into microdroplets by adopting ultrasonic atomization, and carrying out synergistic reaction with gaseous ammonium fluoride and a liquid-phase thorium nitrate solution; a microwave-plasma synergistic fluorination reaction is adopted, and the precursor is heated in a high-purity inert atmosphere to generate crude thorium fluoride; according to the ultra-pure thorium fluoride production process provided by the invention, the purity of thorium fluoride is remarkably improved through the technical means of preparation of a nanoscale precursor through a gas-liquid-solid three-phase reaction, microwave-plasma synergistic fluorination, multi-stage sublimation combined with graphene-based nano trapping membrane purification, intelligent process control, by-product closed-loop recovery and the like; the impurity content is low, and the requirements of nuclear reactor fuel substrates and high-end optical coatings on ultra-high purity are met. The method has the advantages of high yield, high process stability and small purity fluctuation among batches, and the production efficiency and the product consistency are obviously improved.

The invention belongs to the technical field of fly ash solid waste resource utilization, and particularly relates to a method for preparing flaky alumina by using fly ash, which is characterized by comprising the steps of fly ash pretreatment, intermediate preparation and alumina preparation, ammonium fluoride used in the alumina preparation step is a recycling product of fluorine-containing tail gas in the step, and ammonium fluoride used in the alumina preparation step is a recycling product of fluorine-containing tail gas in the step. The preparation method comprises the following specific operation steps: 1) pretreating fly ash, namely treating fly ash with a NaOH solution and an HCl solution to obtain a mixture of quartz and mullite; (2) preparing an intermediate, namely reacting a mixture of quartz and mullite with CeO2 to obtain a K3Al (SO4) 3 intermediate; and 3) preparing aluminum oxide, purifying the K3Al (SO4) 3 intermediate, grinding and mixing the purified K3Al (SO4) 3 intermediate and ammonium fluoride crystals according to the F / Al molar ratio, and roasting at high temperature to obtain a flaky aluminum oxide product. The method has the beneficial effects that the problem of low purity of flaky aluminum oxide in the existing method for preparing the aluminum oxide from the fly ash is solved, and the purity of the flaky aluminum oxide is 99.2-99.8%.

Provided are a wide-temperature-range solid-state electrolyte, a preparation method thereof and use thereof in solid-state lithium metal batteries. The preparation method includes: dissolving a lithium salt and a magnesium salt in a solvent to obtain a mixed salt solution; and mixing the mixed salt solution with an ammonia fluoride solution, subjecting a resulting mixture to reaction, and subjecting a resulting reaction product to centrifugation, washing, and drying in sequence to obtain magnesium-doped lithium fluoride nanoparticles; and mixing the magnesium-doped lithium fluoride nanoparticles, a liquid plasticizer, a polymer monomer and a thermal initiator to obtain a liquid precursor, and subjecting the liquid precursor to curing to obtain the wide-temperature-range solid-state electrolyte, where the polymer monomer is a mixture of ethoxylated trimethylolpropane triacrylate and hexafluorobutyl methacrylate.

The invention belongs to the technical field of chemical detection, and particularly relates to a method for detecting the content of boron in soil and sediment, which comprises the following detection methods: S1, weighing a sample and putting the sample into a digestion tank; s2, adding a digestion solution into the digestion tank; s3, after uniform stirring, putting the digestion tank into a microwave digestion instrument for microwave digestion; s4, after digestion is completed, closing the microwave digestion instrument, and after the digestion tank is cooled to the room temperature, filtering to remove precipitates; s5, transferring the digestion solution into a volumetric flask, and fixing the volume for subsequent analysis; and S6, analyzing the digestion solution by using ICP-OES / MS (Inductively Coupled Plasma-Optical Emission According to the method for detecting the boron content in the soil and the sediment, ammonium fluoride is used for replacing hydrofluoric acid in boron detection of the soil and the sediment, use of toxic reagents is reduced, mannitol is added, a stable complex is formed by mannitol and boron, and the recovery rate of boron is increased.

The invention discloses a controllable preparation method of a methanol-mediated ammonium fluoride-assisted acetic acid etching zeolite adsorption thermal control coating, and belongs to the field of special functional coatings. The invention aims to solve the problems that a zeolite adsorption coating is low in adsorption capacity in an extreme environment and a microporous structure limits diffusion. Zeolite defects are introduced through ammonium fluoride / methanol etching, and then the hierarchical pore zeolite attached thermal control coating is prepared through acetic acid etching. Methanol is adopted as an etching medium, so that ammonium fluoride can be freely transported in a zeolite channel, in-situ hydrolysis and etching of zeolite are carried out until the ammonium fluoride is in contact with water molecules adsorbed in the zeolite channel, and uniform and controllable etching of the outer surface and the interiors of pores of the zeolite is achieved; and meanwhile, the graded zeolite molecular adsorption coating can realize self-balance of body temperature thermal control by virtue of the strong control capability of the layered and three-dimensional space graded pore channel structure on spectral absorption or emission, so that the heat dissipation capability is greatly enhanced, and the thermal control application of the graded zeolite molecular adsorption coating in spacecrafts is facilitated by virtue of the low-absorption-high-emission performance of the graded zeolite molecular adsorption coating.

The invention discloses a plant-based deodorant and a preparation method thereof, and relates to the technical field of high polymer materials. When the plant-based deodorant is prepared, beta-cyclodextrin reacts with paratoluensulfonyl chloride and then reacts with ethylenediamine, and amino modified cyclodextrin is prepared; the plant-based extract is subjected to inclusion with amino modified cyclodextrin, and a cyclodextrin inclusion compound is prepared; the preparation method comprises the following steps: reacting hydroxyethyl cellulose with methacrylic anhydride to prepare double-bond modified cellulose; carrying out hydrothermal reaction on titanium sulfate, the carboxylated multi-walled carbon nanotube, ammonium fluoride and cerous nitrate to prepare a co-doped titanium dioxide / carbon nanotube; coating the co-doped titanium dioxide / carbon nano-tubes with oleic acid to prepare modified nano-particles; and reacting the double-bond modified cellulose with the cyclodextrin inclusion compound, and then copolymerizing with the modified nanoparticles and the comonomer to obtain the plant-based deodorant. The prepared plant-based deodorant has the advantages of good deodorization effect, slow release and photocatalytic degradation.

The invention relates to the technical field of digestion, in particular to a pretreatment method for digesting a glass substrate. The pretreatment method comprises the following four key steps: firstly, crushing and grinding a glass substrate sample into powder so as to increase the contact area and accelerate the subsequent reaction speed; next, adding a mixture of ammonium bifluoride and ammonium fluoride and the powder sample into a polytetrafluoroethylene beaker, adding a small amount of water for wetting, and then adding concentrated hydrochloric acid and concentrated nitric acid to effectively promote the dissolution of the sample; then, the beaker is placed on a heating plate to be heated and digested, and after it is confirmed that the sample is completely digested by monitoring the state of the solution, the sample is cooled to the room temperature. And finally, transferring the digestion solution to a volumetric flask, rinsing the original beaker for multiple times with pure water, and diluting to a constant volume. According to the method, the digestion time is remarkably shortened, the background interference is reduced, the detection precision is improved, and the method is particularly suitable for the requirements of high-end analysis equipment such as AAS and ICP.

The invention discloses a preparation method of high-purity bis (fluorosulfonyl) imide alkali metal salt. The method comprises the following steps: (1) synthesizing bis (chlorosulfonic acid) imide by taking sulfamic acid, chlorosulfonic acid, thionyl chloride and chlorosulfonic acid isocyanate as raw materials; (2) fluorinating the bis (chlorosulfonic acid) imide by ammonium fluoride to obtain bis (fluorosulfonyl) imide ammonium salt; (3) treating the imidodisulfuryl fluoride ammonium salt solution with a strong acid ion exchange column and concentrating under reduced pressure to obtain imidodisulfuryl fluoride; (4) reacting the alkali metal salt with bis (fluorosulfonyl) imide to obtain bis (fluorosulfonyl) imide alkali metal salt; and (5) carrying out a series of purification processes on the bis (fluorosulfonyl) imide alkali metal salt to obtain the high-purity bis (fluorosulfonyl) imide alkali metal salt. The preparation method has the advantages of mild reaction conditions, low danger coefficient in the technological process, easiness in control, no use and generation of corrosive acid, greenness and environmental protection, and high yield and high purity of the bis (fluorosulfonyl) imide alkali metal salt, and is suitable for large-scale industrial application.

The invention belongs to the technical field of new energy batteries, and particularly relates to a method for preparing sodium tetrafluoroborate. The method uses relatively cheap and readily available ammonium fluoride, sodium bicarbonate, and boron trichloride gas as raw materials, wherein ammonium fluoride and sodium bicarbonate are added to an organic solvent and stirred uniformly to obtain a dispersion, boron trichloride gas is introduced, the dispersion is fully reacted, nitrogen is purged from the reaction liquid, and the filtrate is filtered to obtain a filtrate, which is concentrated, crystallized, filtered, washed, and dried to obtain sodium tetrafluoroborate. The method has the advantages of simple process, rapid and thorough reaction, no water by-product, and reduced preparation cost of sodium tetrafluoroborate while achieving a yield and purity equivalent to or even superior to that of existing sodium tetrafluoroborate.

The invention provides high-transparency rare earth doped fluoride glass and a preparation method thereof, and belongs to the technical field of glass. The calcium fluoride ensures high transparency and chemical stability, the magnesium fluoride improves the ultraviolet transmittance and the mechanical strength, and the barium fluoride optimizes the melting fluidity and the rare earth doping uniformity; aluminum fluoride is added to inhibit crystallization and enhance uniformity, the rare earth element realizes optical function regulation and control, and ammonium fluoride provides a fluorine source and reduces impurities; in a preparation link, quick lime is dedusted and then reacts with pure water in proportion, impurities in a calcium nitrate solution are removed by hydrogen peroxide, uniform growth of calcium carbonate crystal nucleuses is controlled by ammonia water and carbon dioxide, and calcium fluoride is synthesized by hydrofluoric acid in proportion and dried at low temperature after plate-frame pressure filtration and purification; after the raw materials are refined through ball milling, the melting temperature is controlled in stages, impurities, reaction integrity and a microstructure are accurately controlled in the whole process, and finally the high-transparency functional glass is prepared.

The invention belongs to the technical field of photoelectric ceramic material manufacturing, and relates to high-density calcium fluoride photoelectric ceramic and an ultralow-temperature preparation method thereof. The method comprises the following steps: S1, wet mixing: weighing calcium hydroxide (Ca (OH) 2) powder and ammonium fluoride (NH4F) powder according to a molar ratio of 1: (1.5-2), and mixing by taking an organic solvent as a medium to form slurry; s2, rapid drying: rapidly drying the slurry obtained in the step (1) to obtain mixed precursor powder; and S3, reaction cold sintering: putting the mixed precursor powder into a mold, and carrying out reaction cold sintering. The sintering temperature used in the method is not higher than 350 DEG C, and the sintering temperature can be changed according to actual needs so as to improve the mechanical property of the ceramic, and the mechanical property is improved by 2-4 times compared with that of a conventional hot pressed sintering sample.

The invention relates to the technical field of niobium-tantalum-iron ore purification, in particular to a method for preparing high-purity tantalum pentoxide and niobium pentoxide from niobium-tantalum-iron ore. The method comprises the following steps: firstly, adding ammonium fluoride and ammonium sulfate to help mineral decomposition and reduce the roasting temperature, then treating the niobium-tantalum iron ore by using a sulfuric acid-hydrofluoric acid mixed solution to fully dissolve niobium-tantalum oxides, then extracting and separating niobium and tantalum by using a specific solvent system, and finally adding ammonia water to precipitate and calcine to obtain the niobium-tantalum iron ore. The high-purity niobium pentoxide and tantalum pentoxide are prepared, the product yield is high, the impurity content is low, and the niobium pentoxide and tantalum pentoxide are suitable for being used as raw materials of capacitor-grade tantalum powder and niobium powder.

The invention discloses a water-containing acid etching solution and a preparation method thereof, the water-containing acid etching solution comprises acid, ammonium fluoride and a surfactant with the molecular formula of # imgabs0 #, Rf is a long-chain alkyl group, N is nitrogen, R1, R2 and R3 are respectively any one of H or short-chain alkyl groups below C4, and M <-> is anions, and tests show that the water-containing acid etching solution has the advantages that due to the fact that the surfactant with the molecular formula of # imgabs1 # is added, the water-containing acid etching solution can be used for preparing the water-containing acid etching solution; the surface tension of the solution is obviously reduced, compared with a buffer oxide etching solution without adding the surfactant, the surface tension is lower, the etching rate is not greatly changed, the contact angle is also obviously reduced, and the content of particles in the product is not increased by the surfactant, so that the solution can be stored by standing for a long time; and the properties cannot be changed in some extreme environments, and the performance is excellent.

The invention relates to a method for high-value recovery of a positive electrode material of a waste lithium iron phosphate battery, which mainly comprises the following steps: adding a lithium iron phosphate positive electrode material, ammonium chloride and hydrogen peroxide into a ball milling tank for grinding, controlling the mass ratio of the ammonium chloride to the lithium iron phosphate positive electrode material to be 5: 2-7: 2, and controlling the volume mass ratio of the hydrogen peroxide to the lithium iron phosphate positive electrode material to be (18-22): 1mL / g; after grinding, washing out the mixture from the ball-milling tank by using deionized water, and then carrying out water leaching treatment to fully leach out metal lithium; excessive ammonium fluoride is added into the filtrate, and reaction liquid and a product lithium fluoride are obtained after reaction; and carrying out adsorption treatment on the reaction liquid by using defluorination resin, regenerating the defluorination resin through elution, combining and concentrating the collected effluent and eluent to obtain an ammonium chloride solution, and recycling the ammonium chloride solution to a chlorination reaction stage. According to the invention, through H2O2 reinforced mechanical chlorination coupling fluorination reaction, nearly total recovery of the waste lithium iron phosphate battery positive electrode material and high value of the product are realized, and the process is simpler and more environment-friendly.

The invention provides porous alumina ceramic and a preparation method thereof, and relates to the technical field of ceramic materials. The invention relates to a preparation method of porous alumina ceramic. The preparation method comprises the following steps: dispersing alpha-cellulose powder in deionized water to form a cellulose suspension; stirring to fully swell the cellulose and form uniform gel, and freeze-drying to obtain a template; dissolving aluminum nitrate hexahydrate, magnesium nitrate hexahydrate and yttrium nitrate hexahydrate in absolute ethyl alcohol to obtain a precursor solution; putting gamma-Al2O3 micro powder and ammonium fluoride into a ball milling tank, adding the precursor solution and a dispersing agent, adding zirconium oxide balls and absolute ethyl alcohol into the ball milling tank, and performing ball milling to obtain ceramic slurry; dipping a template into the ceramic slurry, and performing dipping treatment under a vacuum condition to form a composite green body; and sintering to obtain the porous alumina ceramic. According to the porous aluminum oxide ceramic, the process stability is improved, and the problem that the strength is sharply reduced when the porosity is too high is solved.

The invention provides a method for preparing high-purity flaky alumina based on a hydrolysis method, and belongs to the field of high-purity flaky alumina powder. The method comprises the steps that metal aluminum scraps are pretreated; the method comprises the following steps: putting metal aluminum scraps, an alkaline organic matter catalyst and a morphology control agent into water, and carrying out a hydrolysis reaction at a set temperature for a set time to obtain a reaction mixed solution; carrying out solid-liquid separation, washing and drying on the reaction mixed solution to obtain flaky aluminum hydroxide; and roasting the flaky aluminum hydroxide to remove crystal water so as to obtain high-purity flaky aluminum oxide, wherein the alkaline organic matter catalyst comprises at least one of the following components: tetraethylammonium hydroxide, tetramethylammonium hydroxide, tetrapropylammonium hydroxide and tetrabutylammonium hydroxide; the morphology control agent comprises at least one of ammonium bifluoride and ammonium fluoride. The preparation method disclosed by the invention is simple in process flow, free of an impurity removal process, mild in reaction condition, short in reaction time and free of environmental pollution, and the product is regular in shape and high in purity.

The application discloses a kind of microspheroidal high-entropy spinel type ferrite wave-absorbing materials and preparation method thereof, belong to electromagnetic wave absorbing material technical field, the preparation method includes with the designed molar ratio six metal nitrate is weighed and dissolved in deionized water, then add ammonium fluoride, urea, after stirring, the obtained solution is hydrothermal reaction at a certain temperature for a certain time to obtain precursor, the precursor is calcined to obtain microspheroidal high-entropy spinel type ferrite.The obtained wave-absorbing material is single-phase spinel structure, micron-sized spherical morphology, its chemical formula is MFe2O4;Wherein M=Co, Ni, Cu, Zn, Cr.The microspheroidal high-entropy spinel type ferrite wave-absorbing material and preparation method thereof are used, and the performance of pure ferrite wave-absorbing material can be effectively improved, with the characteristics of simple preparation, strong absorption performance, absorption frequency bandwidth.

The invention provides a preparation process of an ultra-clean high-purity ammonium fluoride solution, and belongs to the technical field of preparation of electronic-grade chemicals. The microcapsule adsorbent is creatively introduced, various purification technologies are combined, the content of metal ions, particles and organic impurities in the ammonium fluoride solution is remarkably reduced, and the strict requirement of the semiconductor industry for high-purity chemicals is met. Wherein the hollow structure of the microcapsule adsorbent and the amide modified cyclodextrin have a synergistic effect, so that the microcapsule adsorbent is endowed with high specific surface area and strong adsorption capacity and has a strong adsorption effect on heavy metal ions and impurity particles, and the polyacrylate shell material enhances the stability of the microcapsule adsorbent in a strong acid / alkali environment. The traditional process has the problem of poor filtering effect and needs to use complex equipment (such as a centrifugal machine and an ultrafiltration device) for multi-step separation, while the method can achieve an efficient separation effect through conventional filtering operation, has the characteristics of high purification efficiency, convenience in separation, stable product quality and the like, and is suitable for industrial production.