4782 results about "Aluminium hydroxide" patented technology

A method for extracting silicon dioxide, alumina and gallium oxide from high-alumina fly ash relates to the technology fields of environmental mineralogy and material, chemical industry and metallurgy. The method comprises the main steps as follows: causing the high-alumina fly ash to react with sodium hydroxide solution; filtering the solution; introducing CO2 to the filtrate for full gelation; cleaning, purifying, drying, grinding and calcining the silica gel after gel filtration to obtain finished white carbon black; adding limestone and a sodium carbonate solution into the filter mass after the reaction and filtration of the high-alumina fly ash and the sodium hydroxide solution; ball grinding the mixture into raw slurry; dissolving out the clinker obtained by baking the raw slurry; subjecting the filtrate to deep desiliconization to obtain sodium aluminate extraction liquid; filtrating the sodium aluminate extraction liquid after subjecting the sodium aluminate extraction liquid to carbon dioxide decomposition; baking the aluminum hydroxide after washing the filter mass to form the aluminum hydroxide product; and extracting the gallium oxide from the carbon dioxide decomposition mother solution and desiliconized solution. The method has the advantages of low material price, simple operating procedures, low investment, low production cost, low energy consumption and less slag.

The invention discloses a preparation method for aluminum oxide by a direct forming method. The method is characterized in that the aluminum oxide is directly formed by a wet filter cake, wherein pore volume is 0.3-0.8ml/g; a specific surface area is 150-300 m<2>/g; and crushing strength is 30-120 N/particle; the preparation process comprises the steps: a) meta-aluminate containing aluminum or a strong acid salt compound is neutralized with a precipitator solution at a temperature of 30-80 DEG C and pH of 6-9; accessory ingredient is added in a neutralizing process; mixture is aged for at least 10min after neutralizing; b) prepared aluminium hydroxide gel is washed by de-ionized water for 4-10 times; dosage of the de-ionized water for each time is 10-40 times of mass of a dried substrate of prepared aluminium hydroxide; a hydrated alumina filter cake is obtained after washing and filtering; content of the aluminium hydroxide in the filter cake is controlled to be 5-50%; and c) the accessory ingredient is added into one or various liquid in the step a) and step b); the filter cake after washing is formed by a normal forming method; and the formed filter cake is dried at a temperature of 80-120 DEG C and calcined at a temperature of 450-1000 DEG C to obtain a finished product of the aluminum oxide.

A stabilized catalyst support having improved hydrothermal stability, catalyst made therefrom, and method for producing hydrocarbons from synthesis gas using said catalyst. The stabilized support is made by a method comprising treating a crystalline hydrous alumina precursor in contact with at least one structural stabilizer or compound thereof. The crystalline hydrous alumina precursor preferably includes an average crystallite size selected from an optimum range delimited by desired hydrothermal resistance and desired porosity. The crystalline hydrous alumina precursor preferably includes an alumina hydroxide, such as crystalline boehmite, crystalline bayerite, or a plurality thereof differing in average crystallite sizes by at least about 1 nm. The crystalline hydrous alumina precursor may be shaped before or after contact with the structural stabilizer or compound thereof. The treating includes calcining at 450° C. or more. Preferred structural stabilizers can include cobalt, magnesium, manganese, manganese, zirconium, boron, aluminum, barium, silicon, lanthanum, oxides thereof, or combinations thereof.

A process for extracting aluminum oxide from powdered coal ash includes such steps as grinding, calcining, mixing with H2SO4 solution, heating while reaction for extracting aluminum oxide, boiling in water, concentrating, cooling while educing out aluminum sulfate crystals, heating for dewatering, heating for decomposing to obtain gamma-Al2O3, and further preparing metallurgy-class aluminum oxide.

The process of preparing alumina includes: the reaction of flyash from circular fluidizing bed and acid to obtain aluminum chloride solution, eliminating silicon impurity, concentrating to crystallize and heating to decompose and to obtain crude alumina product; reaction of crude alumina product and hot alkali solution to obtain sodium aluminate solution; eliminating iron, titanium and other impurity, adding aluminum hydroxide crystal seed into sodium aluminate solution for seed separating decomposition to obtain aluminum hydroxide precipitate; and final calcining aluminum hydroxide to obtain metallurgical alumina. The normal pressure process has no any cosolvent added, and the alumina product has Al2O3 content up to 98 %. The process has small sodium hydroxide consumption, reuse of most of sodium hydroxide, simple operation, low cost, low power consumption, capacity of reducing flyash pollution and other advantages.

A process for extracting alumina from powdered coal ash while generating white carbon black includes such steps as grinding powdered coal ash, activating, adding ammonium sulfate, reacting, adding water, filtering, filling ammonia gas into the filtered liquid to obtain the deposited mixture of aluminum hydroxide and iron hydroxide, adding the solution of sodium hydroxide to dissolve the aluminum hydroxide deposit, adding carbon to obtain pure aluminum hydroxide, and calcining to obtain Al2O3.

A positive electrode active material for a non-aqueous electrolyte secondary battery of this invention includes: a lithium nickel composite oxide containing lithium, nickel, and at least one metal element other than lithium and nickel; and a layer containing lithium carbonate, aluminum hydroxide, and aluminum oxide, the layer being carried on the surface of the lithium nickel composite oxide. The lithium nickel composite oxide is composed such that the ratio of the nickel to the total of the nickel and the at least one metal element is 30 mol % or more. The layer is composed such that the amount of the lithium carbonate is 0.5 to 5 mol per 100 mol of the lithium nickel composite oxide. The total of aluminum atoms contained in the aluminum hydroxide and the aluminum oxide is 0.5 to 5 mol per 100 mol of the lithium nickel composite oxide.

The invention discloses a method for producing alumina by disposing and utilizing industrial solid wastes, in particular to a method for preparing alumina by fly ash, comprising the steps as follows: the fly ash is mechanically activated; the activated fly ash, water and concentrated sulfuric acid react in a reaction kettle under the conditions of heating and pressurizing; the solid is separated from the liquid after the temperature of the reaction is reduced so as to gain aluminium sulfate liquid; the aluminium sulfate liquid is evaporated, concentrated and cooled so as to precipitate aluminium sulphate crystals; the aluminium sulphate crystals are dehydrated and decomposed to gain gama-Al2O3 and SO3; coarse gama-Al2O3 is dissolved in alkaline solution; after the solid is separated from the liquid, the pure sodium aluminate solution is gained; aluminum hydroxide crystal seed is added to the sodium aluminate solution so as to precipitate the aluminum hydroxide; the coarse gama-Al2O3 can be prepared by circularly dissolving the seed-precipitated alkaline solution after vaporization-concentration; the metallurgical alumina can be gained by baking the prepared aluminum hydroxide. The method adds no additive, can lead the alumina in the fly ash to be effectively leached out with the leaching rate more than 90% and saves the energy resource.

The invention discloses a method for producing superfine aluminium hydroxide and aluminium oxide by taking flyash of a recirculating fluidized bed as a raw material. The method comprises the following steps of: a) grinding the flyash, performing wet magnetic separation and deironization, and reacting with hydrochloric acid to obtain hydrochloric acid extract; b) introducing the hydrochloric acid extract into a macroporous cationic resin column for adsorption, after adsorptive saturation of the resin, eluting by using an eluant to obtain eluent containing aluminium chloride and iron chloride; c) removing iron from the eluent by using alkaline solution to obtain solution of sodium metaaluminate; d) adding a dispersing agent into the solution of sodium metaaluminate, and mixing uniformly to obtain dispersion; and e) performing carbon decomposition on the dispersion to obtain the superfine aluminium hydroxide. The superfine aluminium hydroxide is calcined at different temperatures to form gamma-aluminium oxide and alpha-aluminium oxide respectively. Compared with other methods, the method has the advantages of wide sources of raw materials, simple production process and high purity of the products.

The invention discloses a method for dissolving red mud. The method comprises the following specific steps of: mixing Bayer process red mud with white lime in the mass ratio of 1:(0.3-0.9); stirring at the temperature of 80-140 DEG C for reacting for 1-15 hours for calcifying, transforming and dealkalizing; mixing calcified, deformed and dealkalized Bayer process red mud with clear water or a low-concentration sodium aluminate solution in an enclosed container; introducing CO2 into the container to obtain calcified slag containing calcium silicate, calcium carbonate and aluminum hydroxide serving as main components; and extracting aluminum hydroxide from the calcified slag by using a sodium hydroxide solution or an aluminum hydroxide solution. In the method disclosed by the invention, the structure and composition of red mud are changed by adopting calcification transformation and pressurizing calcification transformation methods, so that dealkalization and extraction of aluminum can be realized; and iron is extracted properly, so that the structure and the composition of red mud can meet the requirements of cement production, and the aim of dissolving red mud on a large scale at low cost is fulfilled.

The invention discloses a radiation cross-linked low-smoke halogen-free red phosphorus-free flame retardant material, which comprises the following components of: by weight, 10-80 parts of ethene-vinyl acetate copolymer, 5-30 parts of ethylene-octene copolymer and/or ethene-butene copolymer and/or terpolymer EP rubber, 0-100 parts of polyethylene, 1-20 parts of a polymer compatilizer, 0.5-10 parts of organosilicon polymer, 1-10 parts of a composite anti-oxidant, 0-200 parts of aluminium hydroxide and/or magnesium hydroxide and/or modified aluminium hydroxide and/or modified magnesium hydroxide, 0.1-100 parts of high molecular weight ammonium polyphosphate and/or 0.1-50 parts of a phosphate ester fire retardant and/or 0.1-50 parts of MCA. The material provided by the invention reaches American UL224VW-1 standard when applied in thermal shrinkable tubes, reaches American UL1581VW-1 standard when applied in electric wires and cables, contains no halogen or red phosphorus, and is environmentally friendly.

The invention discloses a polymeric aluminum sulfate synthesis method and discloses a preparation method of a novel alkali-free liquid accelerator based on synthesis of polymeric aluminum sulfate. According to the alkali-free accelerator, an aluminum sulfate solution is neutralized by ammonia water, active aluminum hydroxide gel is prepared, active aluminum hydroxide is filtered, dried and ground into powder, then the aluminum sulfate solution is added, and the polymeric aluminum sulfate is prepared. The alkali-free accelerator comprises, in percentage, 45%-55% of the polymeric aluminum sulfate, 0%-5% of inorganic acid, 0%-2% of a stabilizer, 0%-2% of an organic early strength agent, 0%-2% of an organic tackifier and the balance of water. The cement setting time and the colloidal mortar strength of the accelerator can meet the requirement of first-class accelerators for JC477-2005 sprayed concrete under the condition of the lower mixing amount, and meanwhile, the accelerator is an alkali-free liquid accelerator and can effectively avoid adverse effects caused by excessively high alkali content. The cement types of the accelerator have good adaptability.

The present invention discloses a preparation method for a composite oxide carrier. According to the method of the present invention, a composite oxide dry glue is prepared by the following steps, wherein the steps comprise: firstly preparing an aluminum hydroxide wet filter cake and an aqueous solution containing an IVB group metal complex; adding the wet filter cake to the complex solution, andstrongly stirring; carrying out filtering and drying to obtain the composite oxide dry glue. With the composite oxide dry glue prepared by the method, most of the IVB group metal oxide can be distributed on the surface of aluminum oxide so as to reduce the influence on the pore structure of the aluminum oxide, improve the assistant catalysis effect of the IVB group metal oxide, and improve the pore structure and the surface performance of the composite oxide carrier. In addition, with the present invention, the sulfurization performance of the catalyst adopting the composite oxide carrier as the carrier can be improved, and the loaded active metal is easy to reduce.

The invention discloses a heating-free non-alkali liquid accelerator for jetting concrete and a preparation method of the heating-free non-alkali liquid accelerator. The liquid accelerator is prepared from the following components in percentage by mass: 30%-55% of aluminum sulfate, 3%-10% of aluminium hydroxide, 10%-18% of hydrofluoric acid, 8%-25% of magnesium salt, 1%-8% of alkylol amine, 0.5%-4% of a stabilizer, and 10%-33% of water. The preparation method is characterized by comprising the following processing steps: putting aluminium hydroxide into a reaction kettle; adding water to the reaction kettle, and stirring aluminium hydroxide into paste; slowly adding hydrofluoric acid, and when the temperature reaches 50-55 DEG C, adding aluminum sulfate to stir in batches; after hydrofluoric acid is completely added, adding residual aluminum sulfate and supplementing residual water, so as to obtain reaction liquid; adding the magnesium salt to the reaction liquid, and then adding the alkylol amine and the stabilizer, so that the solution becomes evenly mixed liquid. The accelerator disclosed by the invention has strong adaptability with cement, low energy consumption and good performance, and does not need to be heated in the use procedure.

The present invention provides a powdery composite precursor, which comprises a core of a lithium transition metal oxide, and an aluminum hydroxide-based precipitate layer coated on the surface of the core, and a process to prepare the composite precursor. The preparation process comprises the formation of a water based slurry by dispersing lithium transition metal oxide powder in water, and a precipitation reaction of an aluminum salt solution with a base solution where the lithium transition metal particles act as seed particles, whereby a mechanically stable precipitate layer of homogeneous thickness can be achieved. The composite precursor can be converted into aluminum-containing, e.g., aluminum-doped, lithium transition metal oxide suitable for a cathode active material of lithium rechargeable battery by heat treatment.

The invention relates to a tooth-spherical alumina carrier, a tooth-spherical hydrotreating catalyst and preparation methods thereof. The tooth-spherical alumina carrier comprises the following components in parts by weight: 0.5-4 parts of a peptizing agent, 0.2-2 parts of a lubricant, 0.2-3 parts of a dispersant, 0.3-4 parts of a pore-enlarging agent, and 100 parts of aluminum hydroxide. Because various additives such as the peptizing agent, the pore-enlarging agent, the dispersant, the anionic surfactant and the like in the tooth-spherical alumina carrier disclosed by the invention are greatly reduced, the cost of the tooth-spherical alumina carrier is saved, and the tooth-spherical alumina carrier also has the advantages of large specific surface area, high mechanical strength, and the like.

The invention provides a method to extract aluminum oxide from a fly ash, and relates to a technological method which is to extract aluminum oxide from the fly ash and comprehensively utilize the residue after extracting aluminum oxide. The invention is characterized in the method which is as follows: ammonium sulfate is mixed into the fly ash to sintering, and the solid is dissolved to obtain the solution containing aluminum-ammonium sulfate; the solution is crystallized to form solid aluminium-ammonium sulfate; solid aluminium-ammonium sulfate reacts with ammonia gas to obtain aluminium hydroxide and ammonium sulfate, and aluminium hydroxide and ammonium sulfate are washed and filtrated to obtain solid aluminium hydroxide; solid aluminium hydroxide is calcined to obtain aluminum oxide; ammonium sulfate can be circularly used after being evaporated in the liquid phase. The ammonium sulfate which is used by the method of the invention is weak acidic, the corrosiveness on the equipment is small, and the ammonium sulfate can be used circularly. The whole process is easy to industrial application. The requirement of the corrosion resistance on the equipment is low. The amount of the residue is small which is beneficial to the comprehensive utilization of the residue after extracting the aluminum oxide.

The invention relates to a comprehensive recovery method of waste and old cathode charcoal block of an aluminium electrolytic tank, and belongs to the technical field of comprehensive utilization of industrial solid waste resources. The method is as below: crushing and grinding waste and old cathode charcoal block of the aluminium electrolytic tank at 200-400 DEG C, insulating, removing cyanide, conducting flotation separation on the material with cyanide removed to obtain carbon slag and electrolyte slag, heating the electrolyte slag at 550-800 DEG C to remove carbon impurities, so as to obtain an electrolyte powder, removing to soluble substances in the electrolyte slag by alkali leaching to obtain a carbon powder with high purity, and precipitating a mixture of cryolite and aluminium hydroxide form the alkali leaching liquid by CO2. The invention has the advantages of reasonable process design, simple process, high treatment efficiency, high recovery rate and recycling rate of each material and no secondary pollution, and is applicable to large-scale industrial application.