525results about "Aluminium compounds" patented technology

The application discloses a kind of derived biomass hard carbon material pulverization process, belong to biomass charcoal material processing technical field, first, pulverization process includes the following steps: after drying, the coconut shell derived hard carbon block is carried out primary crushing, while spraying first modifier, obtain the particle size 1~3mm of coarse crushing modified particle;Coarse crushing modified particle is carried out secondary precision crushing under argon atmosphere, while spraying second modifier, obtain the precision crushing modified particle of D 50 Particle size is 15 μm;Precision crushing modified particle is carried out roll grinding spheroidization, while spraying third modifier, obtain the spherical modified particle of D 50 Particle size is 10 μm;Spherical modified particle is carried out flash drying after cooling, then add magnesium stearate to it, after mixing, obtain derived biomass hard carbon material.Then, the application realizes breakthrough in tap density, particle size distribution, first efficiency and other core indexes by the coordination of three-stage gradient modification and progressive pulverization process.

The invention relates to the technical field of catalyst carriers, and discloses reticular porous spherical aluminum oxide as well as a preparation method and application thereof. The preparation method comprises the following steps: (1) mixing an aluminum source, acid, a pore-forming agent, a surfactant and water to obtain pseudo sol; (2) performing ultrasonic treatment and oil ammonia column forming treatment on the pseudo sol obtained in the step (1) to obtain gamma-Al2O3 spherical gel beads; and (3) aging, washing, drying and calcining the gamma-Al2O3 spherical gel beads obtained in the step (2) to obtain the reticular porous spherical alumina. The spherical aluminum oxide prepared by the method has abundant communicated reticular pore channels, is obviously distributed in mesopore and macropore ranges, is beneficial to obviously improving dispersion and loading of a catalyst in an aluminum oxide carrier and improving the performance of petroleum reforming and propane dehydrogenation, and has industrial production utilization value and commercial value.

The invention belongs to the field of functional composite materials, and particularly relates to low-viscosity and high-dispersity aluminum oxide slurry and a preparation method thereof.The low-viscosity and high-dispersity aluminum oxide slurry is prepared from a newly-designed phosphono-carboxyl block copolymer and biquaternary ammonium salt polyether silane as composite modifiers; and efficient anchoring and stable dispersion of the surfaces of alumina particles are realized through the synergistic effect of molecular structures. The phosphono-carboxyl block copolymer is prepared through controllable polymerization and deprotection reaction, and strong chemical bonding is formed between a phosphono group and the surface of aluminum oxide; the biquaternary ammonium salt polyether silane is subjected to click chemical synthesis, and electrostatic adsorption of quaternary ammonium salt and the steric hindrance effect of a polyether chain are combined. When the slurry is prepared, the two modifiers are sequentially added into water, the aluminum oxide powder is added after the pH value is adjusted, finally, the isobutylene maleic anhydride copolymer and the defoaming agent are introduced, and the slurry is obtained through vacuum defoaming and filtering. The slurry prepared by the method has the characteristics of high solid content, low viscosity and good dispersion stability.

The invention discloses a treatment method of a lithium extraction leachate and a production method of lithium carbonate, wherein the treatment method can be used for efficiently recycling an aluminum resource in the leachate. The treatment method of the lithium extraction leachate comprises the following steps that 100, potassium sulfate is added into the lithium extraction leachate, and first liquid is obtained after the potassium sulfate is dissolved; step 200, performing freezing crystallization and solid-liquid separation treatment on the first liquid to obtain crude alum and lithium extraction mother liquor; step 300, dissolving crude alum in a solvent to obtain a second liquid; step 400, performing freezing crystallization and solid-liquid separation treatment on the second liquid to obtain high-purity alum and filtered mother liquor; wherein at least one of the lithium ion concentration, the rubidium ion concentration and the cesium ion concentration in the filtered mother liquor serves as a monitoring object to be monitored, when the monitoring object is larger than or equal to a threshold value, the filtered mother liquor and the lithium extraction mother liquor are mixed, and when the monitoring object is smaller than the threshold value, the filtered mother liquor serves as a solvent of crude alum.

A well-cementing cement stone reinforcing material and the use thereof. The well-cementing cement stone reinforcing material comprises, according to a mass ratio: 30-50 parts of an active spherical α-Al2O3 micropowder, 30-50 parts of spherical fly ash, 5-20 parts of nano metakaolin, 5-10 parts of a hydrophilic rubber powder, and 5-10 parts of hydrophilic carbon fibers. Adding the well-cementing cement stone reinforcing material to a cement slurry of an oil-gas well can promote the generation of a crystal phase having stable high-temperature strength during the hydration process of the cement slurry, thereby improving the high-temperature strength of cement stone; and can solve the problems of a decline in strength and an increase in permeability of the well-cementing cement stone in an ultra-high temperature environment, thereby effectively ensuring the long-term sealing integrity of a wellbore in an ultra-high temperature environment and preventing the annular pressure of an oil-gas well caused by cement ring damage.

The invention discloses a method for removing organic matters in an aluminum oxide solution produced by a Bayer process, which comprises the following steps: mixing evaporated discharged materials with biogas residues produced by biological gas production, stirring and adsorbing, and carrying out solid-liquid separation to obtain an adsorbed solution without the organic matters. The method disclosed by the invention can efficiently absorb organic matters in the sodium aluminate solution, effectively reduce negative effects of the organic matters on a production process, product quality and the like, greatly reduce foam of a decomposition tank, remarkably improve filtering and washing effects, reduce seed refinement, enable an aluminum oxide product to meet quality requirements, effectively improve the quality of the aluminum oxide product and reduce energy consumption; the production efficiency is improved, the production cost is reduced, the stability and sustainability of the production system process are enhanced, and the market competitiveness of products is improved.

The invention provides a method for preparing a poly-aluminum and functional silicon material by activating coal gasification slag and waste hydrochloric acid through microwave synergistic mechanical force, and belongs to the technical field of industrial solid waste recycling. The method comprises the following steps that the coal gasification slag is sequentially subjected to microwave radiation treatment and ball milling, activated slag and waste hydrochloric acid are subjected to an acid leaching reaction, and aluminum-iron-containing leachate and silicon-rich slag are obtained; extracting the aluminum-iron-containing leaching solution to obtain an iron-rich organic phase and a purified aluminum chloride solution; performing thermal polymerization reaction on the purified aluminum chloride solution to obtain polyaluminum chloride; the method comprises the following steps: carrying out alkaline leaching reaction on silicon-rich slag and waste alkali liquor, adding a structure-directing agent into a sodium silicate solution, and sequentially carrying out aging, solution pH value adjustment and crystallization precipitation to obtain mesoporous silica. According to the method, the aluminum-silicon leaching rate is remarkably increased through microwave-mechanical force synergistic activation, synergistic and efficient treatment of the three kinds of waste including the coal gasification slag, the waste hydrochloric acid and the waste alkali liquid is achieved, the technological process is closed, the product additional value is high, and the environmental and economic benefits are remarkable.

The invention provides a pulse-direct current electrochemistry composite deposition process of a nickel-tungsten-phosphorus alloy coating, and belongs to the technical field of coating preparation, and the pulse-direct current electrochemistry composite deposition process comprises the following steps: carrying out silane coupling agent modification treatment on alpha-aluminum oxide; carrying out modification treatment on the hexagonal boron nitride nanosheet by adopting hexadecyl trimethyl ammonium bromide; carrying out polyacrylic acid modification treatment on the nano silicon dioxide; nickel salt, tungsten salt, phosphorus salt, a complexing agent, a buffering agent, a primary brightener, a secondary brightener, a wetting agent, modified aluminum oxide, modified boron nitride, modified silicon dioxide and deionized water are mixed, stirred and heated, and a composite plating solution is obtained; the substrate serves as a cathode, pulse current is applied to the substrate for pulse electroplating, then the current density of the pulse current is continuously and linearly reduced to a target value, and finally direct current electroplating is conducted under the target value; by optimizing the formula of the composite plating solution and the pulse-direct current composite electroplating process, the nickel-tungsten-phosphorus alloy composite plating layer with high hardness, low friction, high wear resistance and corrosion resistance is finally obtained.

The application relates to a modified lithium-rich manganese-based material, a preparation method thereof, a positive plate and a battery. The modified lithium-rich manganese-based material comprises a double-alkali-metal manganese-rich matrix, and the expression of the double-alkali-metal manganese-rich matrix is as follows: Li 1+x Na z Mn a Co b Ni c M 1‑a‑b‑c O 2+x+z‑y D y ; wherein, 0

The invention relates to a ternary positive electrode material and a preparation method thereof, a positive electrode and a battery, the ternary positive electrode material comprises an inner core and a coating layer coating the surface of the inner core, and the coating layer is prepared by roasting raw materials including boehmite and aluminum oxide; wherein the mass ratio of the boehmite to the aluminum oxide is (1-2.33): 1. The surface of the inner core is coated with the coating layer prepared by roasting the raw materials including boehmite and aluminum oxide, so that the stability and the conductivity of the positive electrode coating layer can be improved, and furthermore, the Li < + > mobility is improved, the metal dissolution is reduced, the impedance is reduced, and the cycle performance is improved.

The invention relates to the technical field of solid waste recycling, and particularly provides a circulating fluidized bed system for gasification fly ash resourceful treatment and an aluminum oxide leaching method. The system comprises a hearth, a gas-solid heat exchange bed and an activation reactor. The gasified fly ash and a water glass binder are agglomerated and thickened through a fine powder agglomerator, incineration is conducted through a hearth, and ammonia gas is injected to fix heavy metal; the ash enters an activation reactor, a mullite structure is destroyed by utilizing residual carbon oxygen-enriched combustion (850-950 DEG C) of fly ash, aluminum ions are extracted through gradient acid leaching, acid leaching liquid is neutralized by ammonia water to precipitate aluminum hydroxide, and high-purity aluminum oxide (greater than 99%) and a byproduct ammonium chloride fertilizer are obtained through calcination; the escape rate of fine particles is lower than 10%, the leaching rate of aluminum oxide exceeds 85%, and the treatment cost is reduced by 50% or above compared with that of a traditional method.

The invention discloses a method for preparing polyaluminum chloride from fly ash through mechanical activation and ammonium sulfate roasting and synchronously removing calcium, and particularly relates to the field of hydrometallurgy and solid industrial waste treatment. Adding ammonium sulfate powder into the ground fly ash obtained in the step S1, carrying out a roasting process, carrying out sulfuric acid leaching, adding calcium hydroxide at the same time, and carrying out solid-liquid separation; by adopting the ground fly ash, favorable conditions are created for roasting the ammonium sulfate powder and the aluminum compound. According to the technology, the aluminum element in the fly ash can be efficiently extracted within 30 minutes, resource utilization of solid waste is promoted, aluminum resources in the ash residues are recycled to the maximum extent, and the problems proposed in the background technology are solved.

Low temperature synthesis, growth and doping methods and resulting materials are disclosed. According to an aspect, a method for material transformation includes providing a target material comprising carbon and / or hydrocarbon. The method also includes placing the target material within a fluid comprising a hydrogen source. Further, the method includes applying energy to the target material such that at least some of the target material is transformed to the same material with new beneficial bonding configuration.

The application discloses a preparation method of polyaluminum chloride, and is characterized by comprising the following steps: S1, adding aluminum ash and hydrochloric acid solution into an acidification reaction tank, heating and reacting, filtering after the reaction is completed, and passing the filtrate into a polymerization reaction kettle; S2, adding calcium carbonate into the polymerization reaction kettle in batches to carry out polymerization reaction, stopping the reaction after the calcium carbonate is completely dissolved and the PH of the solution is 3-5; S3, adding polyacrylamide and ferric chloride into the polymerization reaction kettle, and precipitating under 1-3 pa low pressure to obtain sludge and upper liquid, concentrating and crystallizing the upper liquid, crushing the crystal, and obtaining polyaluminum chloride. The application increases an automatic blocking mechanism below a crystallization and crushing tank, automatically blocks when the sub-packaging cylinder is filled with crystals, achieves the purpose of quantitative sub-packaging, and does not cause too much or too little crystals in the sub-packaging cylinder, and does not require staff to be always beside the machine.

The application provides a controllable hydrogen system and a controllable hydrogen method, and the controllable hydrogen system comprises a reactor, an aluminum conveying module, a sodium hydroxide conveying module, a water conveying module and a recovery module; the aluminum conveying module, the sodium hydroxide conveying module and the water conveying module are communicated with the reactor respectively; the reactor is provided with a first outlet and a second outlet; the recovery module comprises a diaphragm filter system, a first inlet of the diaphragm filter system is communicated with the first outlet of the reactor, the diaphragm filter system further comprises a third outlet, and the third outlet is communicated with the reactor; and the second outlet is used for conveying generated hydrogen. The controllable hydrogen method of the application utilizes the controllable hydrogen system to realize efficient controllable hydrogen, and utilizes the diaphragm filter system to recycle by-products and sodium hydroxide, so that the utilization rate of resources is improved.

The present invention relates to methods of preparing aerogel and aerogel slurries, as well as to aerogels and slurries prepared thereby. More particularly, the invention relates to environmentally-friendly methods of preparing aerogels and aerogel slurries in which carbon dioxide is utilised as a reactant and is consumed during the process.

Methods of treating a mineral process stream include adding an effective amount of a cationic polymer mixture to the mineral process stream to form a treated mineral process stream; and processing the treated mineral process stream to yield a mineral product. The cationic polymer mixture includes a first cationic polymer having a weight average molecular weight between about 500 g / mol and about 50,000 g / mol, and a second cationic polymer having a weight average molecular weight of about 100,000 g / mol or greater. The cationic polymer mixture obtains a bimodal distribution of weight average molecular weight. The treated mineral process streams obtain a greater yield of mineral product than mineral process streams processed without the cationic polymer mixture, and a greater yield of mineral product than a mineral process stream processed with only one of the cationic polymers of the cationic polymer mixture added thereto.

The application provides polymeric aluminum sulfate chlorides for pulp and papermaking wastewater and a preparation method thereof, which comprises the following steps: mixing dilute sulfuric acid, aluminum hydroxide, hydrochloric acid and water, stirring, transferring to a reaction kettle, opening a steam warming valve of the reaction kettle, performing steam warming reaction, stopping the steam warming, continuing the reaction of sulfuric acid, hydrochloric acid and aluminum hydroxide until the reaction is completed to obtain a reaction liquid; cooling the reaction liquid, stirring, adding calcium aluminate slurry, adding the calcium aluminate slurry, performing steam warming reaction, keeping warm, completing the reaction to obtain a reaction material; cooling the reaction material, filtering, taking the filtrate and obtaining a target product. The polymeric aluminum sulfate chlorides provided by the application have obvious effects on pulp and papermaking wastewater treatment, can effectively reduce the total soluble solid content and chemical oxygen demand of pulp and papermaking wastewater, and have better treatment effects on pulp and papermaking wastewater and lower costs compared with traditional PAC.

The present application relates to graphene material and its preparation technology, specifically to a method for growing graphene on the surface of non-metallic particles on a large scale, which is suitable for large-scale preparation of graphene-coated non-metallic powder material. The present application uses a two-step method to grow graphene uniformly on the surface of a large number of non-metallic particles: first, mix a large number of non-metallic particles with a carbon source, and form a bulk composite material of non-metallic particles and carbon through low-temperature carbonization; then, pass current to the above bulk composite material using electrodes to heat it to a higher temperature, convert the carbon into graphene, until graphene-coated non-metallic particles are obtained, which are separated from each other, and the high-temperature heating process stops spontaneously. The present application can grow a graphene layer on the surface of a large number of non-metallic particles, the method is easy to scale up, and has the characteristics of good uniformity of graphene coating and high particle separation degree; at the same time, by taking advantage of the large resistance of graphene-coated non-metallic particles which are separated from each other, the high-temperature heating process stops spontaneously.

The invention discloses a preparation method of a pseudo-boehmite catalyst carrier, and relates to the technical field of preparation of catalyst carriers. The preparation method comprises the following steps: dissolving aluminum hydroxide in a sodium hydroxide solution to obtain a reaction solution; introducing compressed carbon dioxide into the reaction liquid to generate pseudo-boehmite slurry, and carrying out filter pressing to obtain a first pseudo-boehmite wet cake; mixing the first pseudo-boehmite wet cake with industrial nitric acid, and performing aging treatment to obtain alumina gel; adding a sodium metaaluminate solution into the alumina gel to adjust the pH value, adding a composite template agent, stirring, and carrying out filter pressing again to obtain a second pseudo-boehmite wet cake; and washing, calcining and crushing the second pseudo-boehmite wet cake to obtain the pseudo-boehmite catalyst carrier. According to the preparation method provided by the invention, the structural performance of the pseudo-boehmite catalyst carrier is improved, the pseudo-boehmite catalyst carrier is of a double-pore distribution structure, and the pseudo-boehmite catalyst carrier can be suitable for various catalytic reactions related to environmental governance and repair and has the advantages of simple preparation process, low cost, excellent product structural performance and the like.

This invention relates to the field of solid waste resource utilization and clean energy technology, specifically providing a cogeneration system and method based on pure combustion of extremely low calorific value coal gangue. The system includes a pretreatment unit, a pure combustion and activation unit, an alumina extraction unit, an energy recovery unit, and a resource utilization unit connected in sequence. The core of the method lies in: feeding extremely low calorific value coal gangue with a calorific value as low as 2300 kJ / kg into a circulating fluidized bed designed based on multiple regeneration and a combustion chamber without heating surfaces, without adding any high calorific value fuel, to achieve stable pure combustion and low-temperature activation at 850-900℃, generating highly active ash slag with an alumina activity index of not less than 79.6%; subsequently, alumina is extracted by acid extraction, and waste heat is simultaneously recovered for power generation and heating; finally, the white mud produced from alumina extraction is used to prepare silicon fertilizer or building materials, and the process wastewater is converted into chemical products such as dust suppressants and passivating agents. This invention is the first to achieve large-scale pure combustion of extremely low calorific value coal gangue, completely eliminating the dependence on high-quality coal and realizing the high-value utilization of all components, resulting in significant environmental and economic benefits.

A high specific surface area mesoporous alumina material with a surface rich in hydroxyl groups is produced by dissolving an aluminum source in an anhydrous organic alcohol solvent containing organic carboxylic acids, slowly and uniformly adding an aqueous ethanol solution to form an alumina sol, drying to obtain an alumina gel, and then treating with high-temperature steam at 400–650°C to obtain a material with... c Mesoporous alumina materials with Al2O3 crystal phase structure, well-developed mesoporous channel structure, high specific surface area and pore volume, and containing 5.0-10.0 mmol / g aluminum hydroxyl groups on the surface of mesoporous pore walls are suitable as catalyst supports for dehydrogenation reactions. The highly uniform loading of metal Pt active components significantly improves the low-temperature reaction activity, selectivity and stability of the catalyst for efficient dehydrogenation of liquid organic hydrogen supports.

The application relates to the technical field of alumina preparation, and particularly discloses a method for reducing the alkalinity of alumina, which comprises the following operations: firstly, mixing alumina with an additive and an organic acid, then performing ball milling, and finally performing calcination; the additive can promote the adhesion of the organic acid and the alumina; the additive and the organic acid are both decomposed into water and carbon dioxide after calcination. The method for reducing the alkalinity of alumina can effectively reduce the pH value of the alumina, does not introduce other impurity ions, is simple to operate, has low energy consumption, and can be used as an adsorbent, a catalyst carrier and an additive in a battery material.

The invention provides a method and a system for recovering chromium and aluminum from a waste chromium catalyst. The method comprises the following steps: carrying out alkali fusion reaction on the waste chromium catalyst and sodium hydroxide to obtain alkali fusion clinker; mixing the alkali fusion clinker with water, pulping, leaching, and carrying out solid-liquid separation to obtain a water leaching solution containing Na2CrO4 and NaAlO2 and a filter cake containing Al2O3; adding a barium salt solution or solid into the aqueous extract containing Na2CrO4 and NaAlO2, reacting to generate a BaCrO4 precipitate, and carrying out solid-liquid separation to obtain a BaCrO4 filter cake and a sodium metaaluminate filtrate; reacting the BaCrO4 filter cake with an inorganic acid, and carrying out solid-liquid separation to obtain a chromic acid solution and a barium sulfate precipitate; and adding an acid solution into the sodium metaaluminate filtrate, adjusting the pH value to 7-8, and carrying out solid-liquid separation to obtain an Al (OH) 3 filter cake. According to the method, Cr (III) in the waste catalyst is directionally converted into Cr (VI) through an alkali fusion oxidation process, then the solubility difference of sodium chromate and sodium metaaluminate in an aqueous solution is fully utilized, the high-selectivity separation characteristic of barium chromate precipitation is combined, the chromium-aluminum separation problem is fundamentally solved, and the finally obtained product is excellent in purity.

The invention discloses fibrous ettringite, a light cement aerogel material for a pipeline lining based on the fibrous ettringite and a preparation method of the light cement aerogel material. The light cement aerogel material for the pipeline lining is prepared from a solution obtained by mixing and stirring fibrous ettringite, cement, an adhesive, a dispersing agent, a hydrophobic component, a foaming component and water through a directional freezing technology, wherein the fibrous ettringite is prepared by heating and stirring a calcium nitrate solution, an aluminum sulfate solution and a sodium hydroxide solution. According to the invention, ettringite which can be uniformly dispersed is synthesized by a ligand-free thermal injection method, and the ettringite, cement and an adhesive raw material are subjected to freezing pore-forming by adopting a directional freezing technology, so that the aerogel material with a special organic-inorganic framework directional ordered pore structure has the characteristics of light weight, high strength, flame retardance and the like; and the overall performance of the pipeline lining material can be improved.

The utility model provides a kind of aluminium smelting aluminium oxide recovery device, including smelting box, the inside of smelting box is provided with partition baffle, the inside space of smelting box is formed by partition baffle and is separated into stirring area and impurity removal area, the inside of stirring area is provided with stirring assembly, for accelerating aluminium dissolution, the top of impurity removal area is provided with impurity removal assembly, the middle of one side of smelting box close to impurity removal assembly is provided with recovery assembly, the device is separated into stirring area and impurity removal area by being provided with partition baffle, stirring assembly accelerates aluminium dissolution in stirring area, so that aluminium oxide impurity is better separated, then aluminium liquid flows into impurity removal area by through-hole in the middle of partition baffle, the mode of this area division and collaborative work makes that impurity removal process is more orderly, avoids the secondary mixing of impurity in smelting process, and further improves impurity removal effect.

The application relates to the technical field of lithium ion batteries, in particular to a coated ternary positive electrode material and a preparation method and application thereof. The coated ternary positive electrode material comprises a ternary positive electrode material and a coating layer on the surface of the ternary positive electrode material, and the coating layer comprises an aluminum oxide chemically modified cobalt compound layer; in the coating layer, the molar ratio of aluminum oxide and the cobalt compound is (0.001-2):100. The provided coated ternary positive electrode material can improve the specific capacity and cycle performance of a battery.

The invention relates to the technical field of preparation of nano aluminum oxide functional materials, in particular to a method for preparing nano aluminum oxide based on gradient centrifugation and a supercritical technology. The method comprises the following steps: carrying out dispersion treatment on a hydrophilic solvent, an aluminum oxide raw material and a dispersing agent to obtain initial slurry; under the condition of constant temperature, the initial slurry is subjected to graded grinding, and refined slurry is obtained; the graded grinding sequentially comprises first-stage grinding, second-stage grinding and third-stage grinding; carrying out gradient centrifugation on the refined slurry to obtain concentrated slurry; the gradient centrifugation sequentially comprises first-stage centrifugation, second-stage centrifugation and third-stage centrifugation; carrying out supercritical drying on the concentrated slurry by using carbon dioxide and a silane coupling agent to obtain coarse alumina powder; and drying the coarse alumina powder in vacuum to obtain the nano alumina. According to the method, through multi-unit collaborative integration of graded grinding, gradient centrifugation and supercritical drying, the production target of high-purity, narrow-particle-size-distribution and low-agglomeration-rate nanometer aluminum oxide is achieved, and the use performance of the nanometer aluminum oxide product is remarkably improved.

A composite product includes molybdenum disulfide particles and palladium particles, in which an average crystallite size of molybdenum disulfide included in the molybdenum disulfide particles determined from a peak of 2θ=14.4°±0.5° obtained by X ray diffraction measurement is 150 nm or less. A catalyst ink includes the composite product and a dispersing medium. A method for producing the composite product includes a step of mixing molybdenum disulfide particles and a palladium solution, in which an average crystallite size of molybdenum disulfide included in the molybdenum disulfide particles determined from a peak of 2θ=14.4°±0.5° obtained by X ray diffraction measurement is 150 nm or less.

The invention relates to the field of preparation of inorganic aerogel materials, and particularly discloses a preparation method of nano aluminum oxide aerogel powder with high specific surface area, high dispersion and low agglomeration. The method comprises the following steps: by taking water-phase fiber / feather-shaped alumina sol as a matrix, introducing styrene-based colloidal particles, obtaining composite powder by combining the steps of spray instantaneous freezing and vacuum freeze-drying, and performing segmented degreasing in an oxidizing atmosphere to remove the colloidal particles, thereby obtaining the composite powder. The prepared nano aluminum oxide aerogel powder is fluffy, has good pore connectivity, can be redispersed and has a high specific surface area. The method does not introduce an organic replacement solvent which is mutually soluble with water, and is simple in process flow and suitable for large-scale production.