Method of production of aluminum oxide

FIELD: hydrometallurgy; production of aluminum oxide.

SUBSTANCE: the invention is pertaining to the field of hydrometallurgy of aluminum compounds and bauxites and may be used for production of aluminum oxide at processing of the bauxites containing alumina. The method of production of aluminum oxide provides for a settling of aluminum hydroxide from a solution of sodium aluminate, its drying and calcination. At that sodium aluminate is produced from aluminum-containing raw material in the capacity of which use a by-product of etching of an aluminum band in production of aluminum constructions. Aluminum-containing raw material is treated at the temperature of 70°C with 3-7 % solution of a sodium hydroxide in amount of 100, 125 or 150 cm3 within 3-5 hours. Produced sediment is filtered out and fed to retreatment with sodium hydroxide, and the filtrate containing sodium aluminate is mixed with about 1-2 M solution of sulfuric acid till obtaining pH = 6.4-7.4, the produced sediment of aluminum hydroxide is filtered out and flushed by water to remove sodium ions, then the produced aluminum hydroxide is heated up in a drying cabinet up to the temperature of 200°C at the rate of heating of 10-20°C /hour and annealed in the muffle furnace within 9 hours up to the temperature of 650°C at the speed of heating of 50°C /hour. The offered method of production of aluminum oxide allows: to reduce the net cost of aluminum hydroxide, to utilize a by-product of etching of an aluminum band in production of aluminum constructions.

EFFECT: the invention allows to reduce the net cost of aluminum hydroxide, to utilize a by-product of etching of an aluminum band in production of aluminum constructions.

1 tbl, 15 ex

 

The invention relates to hydrometallurgy aluminum compounds and can be used to produce alumina in the processing of bauxite containing alumina.

The closest in technical essence and the achieved effect of the present invention is a method of producing aluminum oxide by deposition of the hydroxide of aluminium-containing solutions. In this case, the deposition of the hydroxide conducting continuous introduction into the sodium aluminate solution of nitric acid at pH of 9.0 to 10.0 and a temperature of 90-95° [A.S. No. 1658563 the USSR, CL7C 01 F 7/02, publ. 20.02.96, bull. No. 5].

The disadvantages of this method are the use of an expensive reagent (nitric acid) and the need to use equipment made of special steel, which leads to high cost of this method.

The technical problem of the invention is to reduce the cost of obtaining aluminum oxide, simplifying the process of its receipt.

The technical problem is achieved in that in the method of producing alumina comprising the precipitation of aluminum hydroxide from sodium aluminate solution, drying and calcination, the new is the fact that sodium aluminate is produced from aluminium-containing raw material, which is used as a by-product of etching aluminum tape in the production of aluminum structures, by treating 50 g aluminum is terasawa raw material at a temperature of 70° With 3-7% solution of sodium hydroxide in quantities of 100, 125 or 150 cm3within 3-5 hours, the precipitate is filtered and sent for re-treatment with sodium hydroxide, and the filtrate containing sodium aluminate, mixed with 1-2 M solution of sulfuric acid to obtain a pH of 6.4 to 7.4, the precipitate of aluminum hydroxide is filtered off and washed with water from sodium ions, after which the aluminum hydroxide is heated in an oven to a temperature of 200°C at a heating rate of 10-20 S/h and calcined in a muffle furnace for 9 hours up to 650°C at a heating rate of 50°/H.

The technical result is to simplify the process of obtaining alumina and recycling by-product of etching aluminum tape in the production of aluminium structures.

The method is as follows.

Aluminium-containing raw material, which is used as a by-product of etching aluminum tape in the production of aluminium structures humidity of 40-45% in the amount of 50 g, is treated at a temperature of 70°With 3-7%sodium hydroxide solution in amounts of 100, 125 or 150 cm3within 3-5 hours, the precipitate is filtered and sent for re-treatment with sodium hydroxide, and the filtrate containing sodium aluminate, served in the reactor, where the processing of 1-2 M p is the target of sulfuric acid to obtain a pH of 6.4 to 7.4. The precipitate of aluminum hydroxide is filtered and sent to the reactor for washing water for sodium ions. The obtained aluminum hydroxide is heated in an oven to 200°C at a heating rate of 10-20°/h and calcined in a muffle furnace for 9 hours up to 650°C at a heating rate of 50°S/h

The method is illustrated by the following examples.

Example 1. In the reactor serves 50 g aluminium-containing raw material and mix it with 5%sodium hydroxide solution in the amount of 100 cm3sodium hydroxide (ratio 1:2) at a temperature of 70°C for 3 hours. The precipitate is filtered and sent for re-alkali processing. The filtrate containing sodium aluminate, is sent to the reactor, where it is treated with 1 M solution of sulfuric acid to a pH of 6.8. The precipitate of aluminum hydroxide is separated on a filter and fed into the reactor to flush water from sodium ions, and then send in an oven where heated to 200°C at a heating rate of 20°C/h, and calcined in a muffle furnace for 9 hours up to 650°C at a heating rate of 50°/H. the results of the experiments are shown in the table.

Example 2. In the reactor serves 50 g aluminium-containing raw materials. The results of the experiments are shown in the table.

Example 3. In the reactor serves 50 g aluminium-containing raw material and mix it with 5%sodium hydroxide solution inthe number of 150 cm 3sodium hydroxide (1:3 ratio) at a temperature of 70°C for 3 hours. The precipitate of aluminum hydroxide is filtered and sent for re-alkali processing. The filtrate containing sodium aluminate, is sent to the reactor, where it is treated with 1 M solution of sulfuric acid to a pH of 6.8. The precipitate of aluminum hydroxide is separated on a filter and fed into the reactor to flush water from sodium ions, and then send in an oven where heated to 200°C at a heating rate of 20°C/h, and calcined in a muffle furnace for 9 hours up to 650°C at a heating rate of 50°S/h

Example 4. The method is carried out analogously to example 2, but the processing of sodium hydroxide is carried out at a temperature of 50°C. the results of the experiments presented in the table.

Example 5. The method is carried out analogously to example 2, but the processing of sodium hydroxide is carried out at a temperature of 100°C. the results of the experiments presented in the table.

Example 6. The method is carried out analogously to example 2, but the filtrate is treated with 0.5 M sulfuric acid solution. The results of the experiments presented in the table.

Example 7. The method is carried out analogously to example 2 with the difference that the filtrate is treated with 1.5 M solution of sulfuric acid. The results of the experiments presented in the table.

Example 8. The method is carried out similarly, when the ERU 2, but the precipitation of the aluminum hydroxide of aluminium-containing solution is carried out with sulfuric acid to a pH of 6.0. The results of the experiments presented in the table.

Example 9. The method is carried out analogously to example 2, but the precipitation of the aluminum hydroxide of aluminium-containing solution is carried out with a solution of sulfuric acid up to pH 8.0. The results of the experiments presented in the table.

Example 10. The method is carried out analogously to example 1, but containing aluminum raw material is mixed with 8%sodium hydroxide solution.

Example 11. The method is carried out analogously to example 2, but containing aluminum raw material is mixed with 8% sodium hydroxide solution.

Example 12. The method is carried out analogously to example 3, but containing aluminum raw material is mixed with 8% sodium hydroxide solution.

Example 13. The method is carried out analogously to example 1, but containing aluminum raw material is mixed with 2%sodium hydroxide solution.

Example 14. The method is carried out analogously to example 2, but containing aluminum raw material is mixed with 2% sodium hydroxide solution.

Example 15. The method is carried out analogously to example 3, but containing aluminum raw material is mixed with 2% sodium hydroxide solution.

Table
ExampleThe amount of alkali mlTemperature,°the The concentration of H2SO4Mthe pH of precipitationWeight of aluminum oxide, g
Example 1100701,06,85,72
Example 2125701,06,86,34
Example 3150701,06,86,00
Example 4125501,06,84,05
Example 51251001,06,83,40
Example 6125700,56,84,20
Example 7125701,56,83,00
Example 8125701,06,02,42
Example 9125701,08,01,98
Example 10100701,06,84,90
Example 11125701,06,8-3,80
When is EP 12 150701,06,83,50
Example 13100701,06,8or 4.31
Example 14125701,06,85,00
Example 15150701,06,83,18

As the table shows, the highest yield of aluminum oxide are treated with 50 g of aluminium-containing raw material, 100, 125 or 150 cm33-7%sodium hydroxide solution at a temperature of 70°C for 3-5 hours, the precipitate is filtered and sent for re-treatment with sodium hydroxide, and the filtrate containing sodium aluminate, mixed with 1-2 M solution of sulfuric acid to obtain a pH of 6.4 to 7.4, the precipitate of aluminum hydroxide is filtered off and washed with water from sodium ions, after which the aluminum hydroxide is heated in an oven to a temperature of 200°C at a heating rate of 10-20°/h and calcined in a muffle furnace for 9 h to 650°C at a heating rate of 50°/H. as aluminium-containing raw material using a by-product of etching aluminum tape in the production of aluminium structures.

The proposed method of producing alumina is you:

- to reduce the cost of aluminum oxide;

- dispose of by-product of etching aluminum tape in the production of aluminium structures.

The method of producing alumina comprising the precipitation of aluminum hydroxide from sodium aluminate solution, drying and calcination, wherein the sodium aluminate is produced from aluminium-containing raw material, which is used as a by-product of etching aluminum tape in the production of aluminum structures, by treating 50 g aluminium-containing feedstock at a temperature of 70°With 3-7%sodium hydroxide solution in amounts of 100, 125 or 150 cm3within 3-5 h, the precipitate is filtered and sent for re-treatment with sodium hydroxide, and the filtrate containing sodium aluminate, mixed with 1-2 M solution of sulfuric acid to obtain a pH of 6.4 to 7.4, the precipitate of aluminum hydroxide is filtered off and washed with water from sodium ions, after which the aluminum hydroxide is heated in an oven to a temperature of 200°C at a heating rate of 10-20°/h and calcined in a muffle furnace for 9 h to 650°C at a heating rate of 50°S/h



 

Same patents:

FIELD: inorganic compounds technologies.

SUBSTANCE: invention provides porous composite particles containing alumina component and residue of at least one additional crystal growth inhibitor component dispersed within alumina component, wherein indicated composite particles have (A) specific surface area at least 80 m2/g; (B) average nitrogen-filled pore diameter 60 to 1000 Å; (C) total nitrogen-filled pore volume 0.2 to2.5 cm3/g and (D) average particle size 1 to 15 μm, and where, in indicated composite particles, (i) alumina component contains at least 70 wt % of crystalline boehmite with average crystallite size 20 to 200 Å, γ-alumina obtained from indicated crystalline boehmite, or mixture thereof; (ii) residue of additional is obtained from at least one ionic compound containing ammonium, alkali metal, alkali-earth metal cation, or mixtures thereof and wherein anion is selected from group comprising hydroxyl, silicate, phosphate, sulfate, or mixtures thereof and is present in composite particles in amounts between 0.5 and 10 % of the summary weight of alumina and additional components. Invention also provides a method to obtain composite particles, agglomerated particles prepared therefrom, and a method for hydroprocessing of petroleum feed using above-mentioned agglomerates.

EFFECT: avoided unnecessary calcination before addition of metals to increase average pore size and use of organic solvents for azeotropic removal of water.

36 cl, 2 tbl, 22 ex

FIELD: inorganic compounds technologies.

SUBSTANCE: invention relates to production of activated alumina appropriate as catalyst carrier for petrochemical and organic synthesis, in particular as reforming catalyst carrier. Process comprises continuous precipitation of aluminum hydroxide with pseudoboehmit structure from basic aluminum sulfate solution by neutralization with alkali reagent, filtration, autoclave treatment of resulting aluminum hydroxide precipitate in aqueous ammonia solution at pH 10.0-11.0 of reaction mixture, 135-145°C, and agitation time 1.0-2.0 h, washing of precipitate with chemically desalted water, drying, and final heat treatment.

EFFECT: improved quality of activated alumina and reduced consumption of water in washing of final product.

2 cl, 1 tbl

FIELD: industrial inorganic synthesis.

SUBSTANCE: invention relates to manufacture of ceramic powders, namely to production of optical purity-grade α-alumina. Process comprises autoclave heating of water and aluminum oxide or hydroxide, taken at weight ratio 1:(0.7-1.2), respectively, to synthesis temperature 250-400°C at elevated pressure followed by aging for 20 h at the same temperature and pressure 300-600 atm. After aging, heat treatment is carried out either by way of cooling the mixture to ambient temperature for 24 h at the same pressure or by reducing pressure with rate 20-50 atm/h to atmospheric value at synthesis temperature followed by stopping heating in autoclave.

EFFECT: enabled formation of high-purity microcrystalline alumina.

3 cl, 1 tbl, 2 ex

The invention relates to the field of chemical technology and can be used in the production of oxides and hydroxides of aluminum, various modifications, aluminum salts, etc

The invention relates to chemical technology and can be used in the production of aluminum hydroxide with the structure bayerite and this is of aluminum oxide on its basis, used in the manufacture of catalysts, carriers, etc

The invention relates to a method for producing aluminum hydroxide pseudoboehmite patterns, suitable for receiving the granular active alumina

The invention relates to methods of producing spherical aluminum oxide, which can be used as carriers for catalysts and for the manufacture of entero - and hemosorbent

The invention relates to a wet heat treatment non-caking granular materials and can be used in metallurgical, chemical and cement industry

FIELD: industrial inorganic synthesis.

SUBSTANCE: invention relates to manufacture of ceramic powders, namely to production of optical purity-grade α-alumina. Process comprises autoclave heating of water and aluminum oxide or hydroxide, taken at weight ratio 1:(0.7-1.2), respectively, to synthesis temperature 250-400°C at elevated pressure followed by aging for 20 h at the same temperature and pressure 300-600 atm. After aging, heat treatment is carried out either by way of cooling the mixture to ambient temperature for 24 h at the same pressure or by reducing pressure with rate 20-50 atm/h to atmospheric value at synthesis temperature followed by stopping heating in autoclave.

EFFECT: enabled formation of high-purity microcrystalline alumina.

3 cl, 1 tbl, 2 ex

FIELD: inorganic compounds technologies.

SUBSTANCE: invention relates to production of activated alumina appropriate as catalyst carrier for petrochemical and organic synthesis, in particular as reforming catalyst carrier. Process comprises continuous precipitation of aluminum hydroxide with pseudoboehmit structure from basic aluminum sulfate solution by neutralization with alkali reagent, filtration, autoclave treatment of resulting aluminum hydroxide precipitate in aqueous ammonia solution at pH 10.0-11.0 of reaction mixture, 135-145°C, and agitation time 1.0-2.0 h, washing of precipitate with chemically desalted water, drying, and final heat treatment.

EFFECT: improved quality of activated alumina and reduced consumption of water in washing of final product.

2 cl, 1 tbl

FIELD: inorganic compounds technologies.

SUBSTANCE: invention provides porous composite particles containing alumina component and residue of at least one additional crystal growth inhibitor component dispersed within alumina component, wherein indicated composite particles have (A) specific surface area at least 80 m2/g; (B) average nitrogen-filled pore diameter 60 to 1000 Å; (C) total nitrogen-filled pore volume 0.2 to2.5 cm3/g and (D) average particle size 1 to 15 μm, and where, in indicated composite particles, (i) alumina component contains at least 70 wt % of crystalline boehmite with average crystallite size 20 to 200 Å, γ-alumina obtained from indicated crystalline boehmite, or mixture thereof; (ii) residue of additional is obtained from at least one ionic compound containing ammonium, alkali metal, alkali-earth metal cation, or mixtures thereof and wherein anion is selected from group comprising hydroxyl, silicate, phosphate, sulfate, or mixtures thereof and is present in composite particles in amounts between 0.5 and 10 % of the summary weight of alumina and additional components. Invention also provides a method to obtain composite particles, agglomerated particles prepared therefrom, and a method for hydroprocessing of petroleum feed using above-mentioned agglomerates.

EFFECT: avoided unnecessary calcination before addition of metals to increase average pore size and use of organic solvents for azeotropic removal of water.

36 cl, 2 tbl, 22 ex

FIELD: hydrometallurgy; production of aluminum oxide.

SUBSTANCE: the invention is pertaining to the field of hydrometallurgy of aluminum compounds and bauxites and may be used for production of aluminum oxide at processing of the bauxites containing alumina. The method of production of aluminum oxide provides for a settling of aluminum hydroxide from a solution of sodium aluminate, its drying and calcination. At that sodium aluminate is produced from aluminum-containing raw material in the capacity of which use a by-product of etching of an aluminum band in production of aluminum constructions. Aluminum-containing raw material is treated at the temperature of 70°C with 3-7 % solution of a sodium hydroxide in amount of 100, 125 or 150 cm3 within 3-5 hours. Produced sediment is filtered out and fed to retreatment with sodium hydroxide, and the filtrate containing sodium aluminate is mixed with about 1-2 M solution of sulfuric acid till obtaining pH = 6.4-7.4, the produced sediment of aluminum hydroxide is filtered out and flushed by water to remove sodium ions, then the produced aluminum hydroxide is heated up in a drying cabinet up to the temperature of 200°C at the rate of heating of 10-20°C /hour and annealed in the muffle furnace within 9 hours up to the temperature of 650°C at the speed of heating of 50°C /hour. The offered method of production of aluminum oxide allows: to reduce the net cost of aluminum hydroxide, to utilize a by-product of etching of an aluminum band in production of aluminum constructions.

EFFECT: the invention allows to reduce the net cost of aluminum hydroxide, to utilize a by-product of etching of an aluminum band in production of aluminum constructions.

1 tbl, 15 ex

FIELD: composite materials.

SUBSTANCE: invention relates to catalyst carriers and methods for preparation thereof. Novel porous composite material particles are proposed comprising alumina component and swelled clay component finely dispersed in alumina component in amount effective to raise hydrothermal stability, pore volume, and/or pore mode in the mesopore region in composite material particles as compared to swelled clay-free material. Also proposed are composite material particles and agglomerate particles obtained therefrom as well as a method for hydroprocessing of petroleum feedstock using agglomerates as hydroprocessing catalyst carrier.

EFFECT: increased hydrothermal stability and pore volume.

44 cl, 24 dwg, 19 tbl, 28 ex

FIELD: catalyst carrier preparation methods.

SUBSTANCE: invention has for object development of catalyst carrier based on oxygen-containing aluminum compound having specific chemical analysis, morphologic and texture properties, elevated ability of interacting with catalyst components, and also specified particle size, which catalyst allows preparation of high-strength, active, and stable catalysts. Problem is solved by means of microspherical shape of catalyst carrier including aluminum compounds of formula Al2O3·nH2O having X-ray amorphous structure and prepared via fast partial dehydration of hydroargillite. Carrier represents spheroid particles consisted of hexagonal rods with system of planar parallel pores corresponding to cleavage along face (001). Carrier contains water in amount corresponding to n=0.5-1.0, has particle size 20-250 μm, specific surface 80-250 m2/g, and pore volume 0.1-0.3 cm3/g. Carrier serves for preparation of fluidized bed catalysts used in paraffin hydrocarbon dehydrogenation, oxychlorination, cracking, and other processes. Carrier may also be used as precursor for various hydroxide modifications, including pseudobauhmite, bayerite, various alumina modifications, adsorbents, fillers, fore-retardants and the like.

EFFECT: increased strength, activity, and stability of catalysts.

9 cl, 3 dwg, 2 tbl, 5 ex

FIELD: paper-and-pulp industry.

SUBSTANCE: invention relates to pigment, which can be used in manufacture of paper with filler, coated paper, and cardboard. Calcium hydroxide and calcium carbonate powders taken in proportion between 1.0:2.2 and 1.0:23.5 are added to vigorously stirred water, after which temperature of mixture is raised to 80-85°C and resulting reaction mixture is kept being stirred for 90-180 min to form dispersion of pigment containing 20-35% solids.

EFFECT: improved quality of pigment at lower cost and extended application area.

3 tbl

FIELD: sorbents.

SUBSTANCE: invention concerns modified sorbents applicable in food-processing and chemical industries. Modified sorbent is prepared from aluminum-containing raw material, namely from aluminum band etching waste in manufacture of aluminum structures. Fifty gram of raw material is treated for 3-5 h at 70°C with 3-7% sodium hydroxide solution in amounts 100. 125 or 150 cc. Resulting precipitate is filtered and sent to re-treatment with sodium hydroxide and sodium aluminate containing filtrate is mixed with 1-2 M sulfuric acid solution so that pH reaches 6.4-7.4. Aluminum hydroxide precipitate obtained is filtered and rinsed with water to remove sodium ions, heated in drying box to 200°C at heating rate 10-20°C/h, and calcined in muffle kin for 5 h to 450°C at heating rate 50°C/h to give pulverulent aluminum oxide. The latter is treated for 10-12 min with aqueous solution of surfactant OP-10 with concentration 0.019-0.022% at 39-41°C and aluminum oxide-to-surfactant ratio 1:10, after which dried at room temperature.

EFFECT: increased adsorption capacity, reduced production cost, and utilized production waste.

1 tbl, 5 ex

FIELD: structural chemistry and novel catalysts.

SUBSTANCE: invention provides composition including solid phase of aluminum trihydroxide, which has measurable bands in x-ray pattern between 2Θ=18.15° and 2Θ=18.50°, between 2Θ=36.1° and 2Θ=36.85°, between 2Θ=39.45° and 2Θ=40.30°, and between 2Θ=51.48° and 2Θ=52.59°, and has no measurable bands between 2Θ=20.15° and 2Θ=20.65°. Process of preparing catalyst precursor composition comprises moistening starting material containing silicon dioxide-aluminum oxide and amorphous aluminum oxide by bringing it into contact with chelating agent in liquid carrier and a metal compound; ageing moistened starting material; drying aged starting material; and calcining dried material. Catalyst includes carrier prepared from catalyst composition or catalyst precursor and catalytically active amount of one or several metals, metal compounds, or combinations thereof. Catalyst preparation process comprises preparing catalyst carrier from starting material containing silicon dioxide-aluminum oxide and amorphous aluminum oxide by bringing it into contact with chelating agent and catalytically active amount of one or several metals, metal compounds, or combinations thereof in liquid carrier, ageing starting material; drying and calcinations. Method of regenerating used material involves additional stage of removing material deposited on catalyst during preceding use, while other stages are carried out the same way as in catalyst preparation process. Catalyst is suitable for treating hydrocarbon feedstock.

EFFECT: improved activity and regeneration of catalyst.

41 cl, 3 dwg, 8 tbl, 10 ex

FIELD: pulp and paper industry; methods of production of the pigment for manufacture of the cardboard and paper.

SUBSTANCE: the invention is pertaining to the method of production of the pigment for manufacture of the cardboard and paper and may be used in pulp and paper industry at production of the filled paper, the coated paper and the cardboard. In the water at intense stirring feed powders of calcium hydrate and calcium carbonate at the ratio of the indicated components accordingly from 1.0:2.2 up to 1.0:12.9. The produced suspension is gradually added with aluminum sulfate at its ratio to the total mass of the calcium hydroxide and calcium carbonate from 1.0:0.85 up to 1.0:4.30. Then the temperature of the mixture is increased up to 8О-85°С and the produced reaction mixture is kept at stirring within 90-180 minutes with formation of the dispersion of the pigment with the share of the dry substances in it equal to 20-35 %. Then the dispersion is dried and grinded into the powder. The powder is dispersed in the water containing the given amount of the dissolved coolant and-or binding - starch or polyvinyl alcohol. The technical result of the invention production of the pigment with the new properties, that allow to expand the field of its application at manufacture of various types of the cardboard and the paper.

EFFECT: the invention ensures production of the pigment with the new properties, expansion of the field of its application at manufacture of various types of the cardboard and the paper.

2 tbl

Up!