CN104386723B - A kind of preparation method of high-purity alpha-alumina - Google Patents
A kind of preparation method of high-purity alpha-alumina Download PDFInfo
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- CN104386723B CN104386723B CN201410626394.1A CN201410626394A CN104386723B CN 104386723 B CN104386723 B CN 104386723B CN 201410626394 A CN201410626394 A CN 201410626394A CN 104386723 B CN104386723 B CN 104386723B
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- PNEYBMLMFCGWSK-UHFFFAOYSA-N Alumina Chemical compound [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 title claims abstract description 57
- 238000002360 preparation method Methods 0.000 title claims abstract description 20
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims abstract description 48
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 35
- 239000004411 aluminium Substances 0.000 claims abstract description 35
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 32
- WNROFYMDJYEPJX-UHFFFAOYSA-K aluminium hydroxide Chemical compound [OH-].[OH-].[OH-].[Al+3] WNROFYMDJYEPJX-UHFFFAOYSA-K 0.000 claims abstract description 30
- 229910021502 aluminium hydroxide Inorganic materials 0.000 claims abstract description 28
- 239000000843 powder Substances 0.000 claims abstract description 25
- 238000005245 sintering Methods 0.000 claims abstract description 23
- 235000015895 biscuits Nutrition 0.000 claims abstract description 19
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 15
- 239000007788 liquid Substances 0.000 claims abstract description 13
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 claims abstract description 12
- 238000006460 hydrolysis reaction Methods 0.000 claims abstract description 10
- 239000002002 slurry Substances 0.000 claims abstract description 9
- 239000012498 ultrapure water Substances 0.000 claims abstract description 9
- 238000001354 calcination Methods 0.000 claims abstract description 7
- 239000002245 particle Substances 0.000 claims abstract description 7
- 230000018044 dehydration Effects 0.000 claims abstract description 6
- 238000006297 dehydration reaction Methods 0.000 claims abstract description 6
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 5
- 229910002804 graphite Inorganic materials 0.000 claims abstract description 5
- 239000010439 graphite Substances 0.000 claims abstract description 5
- 238000003723 Smelting Methods 0.000 claims abstract description 4
- 239000000463 material Substances 0.000 claims description 31
- 239000000919 ceramic Substances 0.000 claims description 16
- 238000006243 chemical reaction Methods 0.000 claims description 10
- 238000000889 atomisation Methods 0.000 claims description 9
- 238000000748 compression moulding Methods 0.000 claims description 8
- 238000001035 drying Methods 0.000 claims description 7
- 230000007062 hydrolysis Effects 0.000 claims description 7
- 238000001816 cooling Methods 0.000 claims description 6
- 239000010419 fine particle Substances 0.000 claims description 6
- 238000010792 warming Methods 0.000 claims description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 6
- 230000003301 hydrolyzing effect Effects 0.000 claims description 5
- 239000012535 impurity Substances 0.000 claims description 5
- 239000004677 Nylon Substances 0.000 claims description 4
- 229910006295 Si—Mo Inorganic materials 0.000 claims description 4
- 229910010293 ceramic material Inorganic materials 0.000 claims description 4
- 239000007789 gas Substances 0.000 claims description 4
- 238000010438 heat treatment Methods 0.000 claims description 4
- 229920001778 nylon Polymers 0.000 claims description 4
- 229910052573 porcelain Inorganic materials 0.000 claims description 4
- 239000004743 Polypropylene Substances 0.000 claims description 2
- 239000004744 fabric Substances 0.000 claims description 2
- 239000012467 final product Substances 0.000 claims description 2
- -1 polypropylene Polymers 0.000 claims description 2
- 229920001155 polypropylene Polymers 0.000 claims description 2
- 238000000034 method Methods 0.000 abstract description 6
- 238000010298 pulverizing process Methods 0.000 abstract description 3
- 239000000126 substance Substances 0.000 abstract description 3
- 238000003837 high-temperature calcination Methods 0.000 abstract 1
- 239000011261 inert gas Substances 0.000 abstract 1
- 238000007493 shaping process Methods 0.000 abstract 1
- 239000000047 product Substances 0.000 description 7
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 6
- 238000005516 engineering process Methods 0.000 description 5
- 239000007864 aqueous solution Substances 0.000 description 4
- 239000007921 spray Substances 0.000 description 4
- 239000000356 contaminant Substances 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 239000010409 thin film Substances 0.000 description 3
- XFBXDGLHUSUNMG-UHFFFAOYSA-N alumane;hydrate Chemical compound O.[AlH3] XFBXDGLHUSUNMG-UHFFFAOYSA-N 0.000 description 2
- 238000004140 cleaning Methods 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 229910001873 dinitrogen Inorganic materials 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 230000004927 fusion Effects 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 229910052594 sapphire Inorganic materials 0.000 description 2
- 239000010980 sapphire Substances 0.000 description 2
- 239000000758 substrate Substances 0.000 description 2
- 238000004381 surface treatment Methods 0.000 description 2
- 241001062009 Indigofera Species 0.000 description 1
- 229910020073 MgB2 Inorganic materials 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- PZKRHHZKOQZHIO-UHFFFAOYSA-N [B].[B].[Mg] Chemical compound [B].[B].[Mg] PZKRHHZKOQZHIO-UHFFFAOYSA-N 0.000 description 1
- 150000004703 alkoxides Chemical class 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 239000007770 graphite material Substances 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000007712 rapid solidification Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 238000013022 venting Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
- C01F7/00—Compounds of aluminium
- C01F7/02—Aluminium oxide; Aluminium hydroxide; Aluminates
- C01F7/42—Preparation of aluminium oxide or hydroxide from metallic aluminium, e.g. by oxidation
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/10—Solid density
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Inorganic Chemistry (AREA)
- Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
- Compositions Of Oxide Ceramics (AREA)
Abstract
The invention discloses a kind of preparation method of high-purity alpha-alumina, being specially the high-purity aluminium ingot after by process loads in smelting furnace, first vacuumize and fill high pure nitrogen continuously, then heat up and aluminium ingot melted, aluminium liquid obtains active aluminum powder by graphite catheter through high-pressure inert gas+high purity water+high speed rotating rotating disk, aluminium hydroxide slurry is generated through hydrolysis reaction, then by centrifuge dehydration, oven dry, pulverizing, stable alumina powder is obtained by the calcining of high-temperature calcination stove, re-use briquetting press powder pressing is shaping, sinter to density and be greater than 3.7g/cm
3.The preparation method of high purity aluminium oxide of the present invention, whole equipment flowsheet is without the need to adding any chemical feedstocks, simple to operate, pollution-free, is easy to industrialization; Obtained aluminum oxide purity can reach more than 99.9992%, and mean particle size is below 0.4 micron, and the aluminum oxide biscuit after high temperature sintering, density can reach 3.7g/cm
3above, the output with the long brilliant stove of isometric(al) has been increased substantially.
Description
Technical field
The invention belongs to field of material preparation, be specifically related to a kind of preparation method of high-purity alpha-alumina.
Background technology
High-purity ultra-fine alumina be purity more than 99.999%, granularity is at micron order even nano level.Its purity, fineness are directly connected to development and the performance of LED technology Application Areas and market outlook.
In recent years, LED sapphire crystal ultra high purity nitric oxide aluminium polycrystal market keeps sustainable growth in the world, and add up according to international industry analysis, market annual growth was that namely 30%, 2011 world market demands reach 10000 tons in recent years, and within 2014, demand can reach 20000 tons.If consider the application of ultra high purity nitric oxide aluminium in other high-tech sector industries, within its year, demand can reach 4-5 ten thousand tons for 2014, nearly 10,000,000,000 yuan of its market capacity.
Sapphire crystal ultra high purity nitric oxide aluminium crystalline substance material is widely used in multiple fields of industry, national defence and scientific research, as high temperature resistant infrared window etc.It is also a kind of broad-spectrum monocrystal chip material simultaneously, and being the first-selected substrate of current indigo plant, purple, white light emitting diode (LED) and blue laser (LD) industry, is also important superconducting thin film substrate.Except making Y-system, the high-temperature superconducting thin films such as La-system also can be used in growth novel practical MgB2 (magnesium diboride) superconducting thin film outward.
At present, preparing the main method of high purity aluminium oxide is both at home and abroad alkoxide process, rectifying aluminium alcoholates, membrane separation process, although these methods can make the aluminum oxide that purity reaches 5N level, its technics comparing is complicated, and cost is high, even can cause certain pollution to environment.
Summary of the invention
In order to solve high purity aluminium oxide preparation technology more complicated in prior art, cost is high, even can cause the defect of certain pollution to environment, the invention provides a kind of preparation method of high-purity alpha-alumina.
For solving the problems of the technologies described above, the invention of this reality adopts following technical scheme:
A preparation method for high-purity alpha-alumina, comprises the following steps that order connects:
A, melted at 850-900 DEG C by high-purity aluminium ingot, obtain aluminium liquid, aluminium liquid is flowed out with the speed of 2.1-2.5kg/min by graphite catheter;
B, the aluminium liquid that steps A flowed out by the atomization of high pure nitrogen, and are cooled by high purity water, and wherein, the purity of high pure nitrogen is 99.999%, and the pressure of high pure nitrogen is 4.0-4.5MPa, and high-purity resistivity of water is 15-18M Ω;
C, step B gained material is shattered into activated aluminum powder fine particle through the cooling rotary plate of high speed rotating;
D, step C gained activated aluminum powder fine particle put into hydrolytic reaction pot hydrolysis and generate aluminium hydroxide, then centrifuge dehydration, microwave drying, comminution by gas stream;
E, step D gained material is warming up to 1150-1200 DEG C with the speed of 5 DEG C/min in calcining furnace, is then incubated 3.5-4h, obtains stable alumina powder;
F, by the briquetting press compression moulding of the alumina powder of step e gained, obtaining density is 1.8-2.0g/cm
3aluminum oxide biscuit, during compacting, pressure is 60-70MPa, then uses high temperature sintering furnace at 1650-1700 DEG C, biscuit is sintered to density and is greater than 3.7g/cm
3, to obtain final product.
Applicant finds after deliberation: melted under 850-900 DEG C of high temperature by high-purity aluminium ingot raw material, obtains aluminium liquid viscosity and the comprehensive atomizing effect of energy consumption is best, if temperature is too high, aluminium liquid is crossed and released, and when atomization is dusted not easily rapid solidification; The powder that step e is reunited, through high temperature, changes into rapidly the thinner and α-Al that crystalline phase is more stable of granularity
2o
3powder.Adopt above-mentioned preparation method, not only ensure that the purity of products obtained therefrom, crystalline phase stability and mechanical property, and increase substantially the output with the long brilliant stove of isometric(al); And preparation method is simple, advantage of lower cost, and to environment without any pollution.
Preferably, in step C, the cooling cone dish rotating speed of high speed rotating is 2500-2900r/min, and the fine grain particle diameter of gained activated aluminum powder is 0.5-2 micron.Granularity and the performance of products obtained therefrom can be ensured so further.
Preferably, in steps A, high-purity aluminium ingot material purity is greater than 99.9992%.The purity of products obtained therefrom can be ensured so further.
Preferably, in steps A, before high-purity aluminium ingot fusing, smelting furnace is vacuumized, be then filled with high pure nitrogen continuously, until atomization terminates rear stopping be filled with nitrogen.Can prevent from like this in smelting furnace temperature-rise period, causing the graphite material of the inside oxidized, purity and the performance of products obtained therefrom can be ensured further.
Preferably, in step D, hydrolytic reaction pot is made up of polypropylene material.Material can be avoided like this to contact with metal impurities, to ensure the purity of material.Can heat to reactor when temperature of charge reduces, keep there is certain temperature in still, accelerate speed of reaction.The liquid of certain liquid level can only be released after hydrolysis a couple of days, avoid the grey aluminium powder of non-complete reaction to be mixed in aluminium hydroxide, ensure its purity.
Preferably, in step D, during hydrolysis, the quality proportioning of activated aluminum powder fine particle and high purity water is 1:3, adopts batch type during hydrolysis.Purity and the performance of products obtained therefrom can be ensured so further.
Preferably, in step D, centrifuge dehydration by aluminum hydroxide solution more than 70% moisture filter, the aluminium hydroxide slurry obtained is trapped on the above filter cloth of 10000 order.Further can ensure purity and the performance of products obtained therefrom like this.
Preferably, in step D, microwave drying is: be laid on the guipure of microwave dryer by gained aluminium hydroxide slurry, and guipure is tetrafluoro material, and microwave dryer Fen Liang district heats, temperature is respectively 100 DEG C and 150 DEG C, two zone lengths are respectively 3.5m and 2.3m, and material runs with the speed that 0.5m/min is adjustable, and material moves to exit, pulverize through nylon roller, obtain dry aluminium hydroxide.Use microwave drying, comparatively baking oven, simple to operate, speed is fast and output is large, and without the need to setting excessive temperature, twoth district set 100 DEG C and 150 DEG C respectively, reduces manpower.Above-mentioned material first through excess temperature be 100 DEG C, length is the district of 3.5m, and then through excess temperature be 150 DEG C, length is 2nd district of 2.3m.
Preferably, in step D, comminution by gas stream is: utilize micronizer mill, under the air pressure of 3MPa, is pulverized by the aluminium hydroxide pulverized, obtains the aluminium hydroxide powder that granularity is below 2um.Granularity and the purity of products obtained therefrom can be ensured so further.
Preferably, step D gained material is contained into 99 porcelain dishes, is warming up to 1150-1200 DEG C, is then incubated 3.5-4h in calcining furnace with the speed of 5 DEG C/min, obtains stable alumina powder; In step F, compression moulding is pressed down by the ceramic die of the alumina powder briquetting press of step e gained, and pressure is 60-70MPa, then full extruding dies, and obtaining density is 1.8-2.0g/cm
3aluminum oxide biscuit; In step F, the liner of sintering oven is alumina ceramic material, heating unit is Si-Mo rod, if the first baker more than one week of new sintering oven, be warmed up to 1650-1700 DEG C again to make impurity volatilization in furnace lining, the aluminum oxide of compression moulding bulk loaded in ceramic crucible after baker, be then placed on ceramic burning-resisting board advanced in high temperature sintering furnace by push rod and sinter, the temperature rise rate of sintering is 5 DEG C/min.
Ceramic die is adopted during step F briquetting, avoid, because in the materials such as stainless steel, metallic element is mixed in material, having a strong impact on its purity, the improvement of step F prevents furnace atmosphere reaction contaminant material, affect its purity, sintering is that frangible biscuit is harder, density is larger, performance is better in order to make.
The NM technology of the present invention is all with reference to prior art.
The preparation method of high purity aluminium oxide of the present invention, whole equipment flowsheet is without the need to adding any chemical feedstocks, simple to operate, pollution-free, is easy to industrialization; Obtained aluminum oxide purity can reach more than 99.9992%, and mean particle size is below 0.4 micron, and the aluminum oxide biscuit after high temperature sintering, density can reach 3.7g/cm
3above, the output with the long brilliant stove of isometric(al) has been increased substantially.
Accompanying drawing explanation
Fig. 1 is the preparation flow figure of high purity aluminium oxide of the present invention.
Fig. 2 is hydrolytic reaction pot structural representation.
Fig. 3 is microwave dehydration device structure schematic diagram.
Fig. 4 is the ceramic die structural representation of briquetting press.
Fig. 5 is embodiment 1 gained aluminum oxide biscuit XRD diffractogram.
In figure, 1, stir shaft entrance and motor position; 2, opening for feed; 3, venting port; 4, discharge port; 5, stock shelf; 6, tolerance is suppressed; 7, microwave cavity; 8, discharge rack; 9, ceramic patrix; 10, mould in pottery; 11, ceramic counterdie.
Embodiment
In order to understand the present invention better, illustrate content of the present invention further below in conjunction with embodiment, but content of the present invention is not only confined to the following examples.
Embodiment 1:
The preparation method of high purity aluminium oxide: first, take purity as the high-purity aluminium ingot of more than 5N be raw material, load in high purity graphite crucible after surface treatment cleaning, to vacuumizing in molten aluminium stove and passing into trace nitrogen gas continuously, be incubated after aluminium stove fusion is warming up to 850 DEG C, then atomization rotating disk is started, the cooling rotary plate rotating speed of high speed rotating is 2500r/min, open spray equipment (high-purity water resistivity is 15M Ω) subsequently, pass into high pure nitrogen (purity is 99.999%), gaseous tension is 4.0MPa, atomization rotating disk, high purity water, after high pure nitrogen is stable, release aluminium liquid, be 2.1kg/min by the aluminium flow quantity discharged in catheter, obtained activated aluminum powder, the activated aluminum powder sprayed in spray chamber is injected hydrolysis reaction in reactor according to the ratio of aluminium, water 1:3, obtains the aluminium hydroxide aqueous solution, by the aluminium hydroxide aqueous solution, by the dehydrating function of whizzer, obtain aluminium hydroxide slurry, now slurry water content about 28%, through microwave drying treatment, in aluminium hydroxide, large quantity of moisture is discharged, pulverized by the nylon roller of discharge port, obtain dry aluminium hydrate powder, microwave dryer Fen Liang district heats, temperature is respectively 100 DEG C and 150 DEG C, and two zone lengths are respectively 3.5m and 2.3m, and material runs with the speed that 0.5m/min is adjustable, utilize micronizer mill, under the air pressure of 3MPa, the aluminium hydroxide pulverized is pulverized again, obtain the aluminium hydroxide powder that granularity is below 2um, the aluminium hydroxide that pulverization process is crossed is contained into 99 porcelain dishes, puts into 1150 DEG C of calcining furnaces and calcine, material heats up with the temperature rise rate of 5 DEG C/min, is then incubated 3h.The powder of reuniting, through high temperature, changes into rapidly the thinner and α-Al that crystalline phase is more stable of granularity
2o
3powder; Get certain amount of alumina powder, pour in the ceramic die of briquetting press and press down, pressure is 60MPa, then full extruding dies, and obtaining density is 1.8g/cm
3aluminum oxide biscuit; Sintering oven liner is alumina ceramic material, heating unit is Si-Mo rod, new sintering oven needs baker more than one week, be warmed up to 1650 DEG C to make impurity volatilization in furnace lining, prevent furnace atmosphere reaction contaminant material, affect its purity, after baker, the aluminum oxide biscuit of compression moulding is loaded in ceramic crucible, be placed on ceramic burning-resisting board advanced in 1650 DEG C of high temperature sintering furnaces by push rod and sinter, sintering is to make frangible biscuit harder and density is larger, biscuit is with the temperature rise rate of 5 DEG C/min sintering, and be then incubated 3.5h, obtaining density is 3.7g/cm
3, the aluminum oxide biscuit that purity is 99.9992%, particle diameter is 0.4 micron, even particle size distribution, meets customer requirement, specifically as shown in table 1.
The analytical results of table 1 embodiment 1 gained aluminum oxide
Embodiment 2:
The preparation method of high purity aluminium oxide of the present invention: first, take purity as the high-purity aluminium ingot of more than 5N be raw material, load in high purity graphite crucible after surface treatment cleaning, to vacuumizing in molten aluminium stove and passing into trace nitrogen gas continuously, be incubated after aluminium stove fusion is warming up to 890 DEG C, then atomization rotating disk is started, the cooling rotary plate rotating speed of high speed rotating is 2900r/min, open spray equipment (high-purity water resistivity is 15M Ω) subsequently, pass into high pure nitrogen, gaseous tension is 4.2MPa, atomization rotating disk, high purity water, after high pure nitrogen is stable, release aluminium liquid, be 2.5kg/min by the aluminium flow quantity discharged in catheter, obtained activated aluminum powder, the activated aluminum powder sprayed in spray chamber is injected hydrolysis reaction in reactor according to the ratio of aluminium, water 1:3, obtains the aluminium hydroxide aqueous solution, by the aluminium hydroxide aqueous solution, by the dehydrating function of whizzer, obtain aluminium hydroxide slurry, now slurry water content about 28%, through microwave drying treatment, in aluminium hydroxide, large quantity of moisture is discharged, pulverized by the nylon roller of discharge port, obtain dry aluminium hydrate powder, microwave dryer Fen Liang district heats, temperature is respectively 100 DEG C and 150 DEG C, and two zone lengths are respectively 3.5m and 2.3m, and material runs with the speed that 0.5m/min is adjustable, utilize micronizer mill, under the air pressure of 3MPa, the aluminium hydroxide pulverized is pulverized again, obtain the aluminium hydroxide powder that granularity is below 2um, the aluminium hydroxide that pulverization process is crossed is contained into 99 porcelain dishes, puts into 1200 DEG C of calcining furnaces and calcine, material heats up with the temperature rise rate of 5 DEG C/min, is then incubated 4h.The powder of reuniting, through high temperature, changes into rapidly the thinner and α-Al that crystalline phase is more stable of granularity
2o
3powder; Get certain amount of alumina powder, pour in the ceramic die of briquetting press and press down, pressure is 70MPa, then full extruding dies, and obtaining density is 2.0g/cm
3aluminum oxide biscuit; Sintering oven liner is alumina ceramic material, heating unit is Si-Mo rod, new sintering oven needs baker more than one week, be warmed up to 1700 DEG C to make impurity volatilization in furnace lining, prevent furnace atmosphere reaction contaminant material, affect its purity, after baker by packaged for the aluminum oxide cake of compression moulding enter in ceramic crucible, be placed on ceramic burning-resisting board advanced in 1700 DEG C of high temperature sintering furnaces by push rod and sinter, sintering is to make frangible biscuit harder and density is larger, then biscuit is incubated 4h with the temperature rise rate of 5 DEG C/min sintering, and obtaining density is 3.8g/cm
3, purity is the high purity aluminium oxide biscuit of 99.9992%, even particle size distribution.
Claims (5)
1. a preparation method for high-purity alpha-alumina, is characterized in that: comprise the following steps that order connects:
A, melted at 850-900 DEG C by high-purity aluminium ingot, obtain aluminium liquid, aluminium liquid is flowed out with the speed of 2.1-2.5kg/min by graphite catheter;
B, the aluminium liquid that steps A flowed out by the atomization of high pure nitrogen, and are cooled by high purity water, and wherein, the purity of high pure nitrogen is 99.999%, and the pressure of high pure nitrogen is 4.0-4.5MPa, and high-purity resistivity of water is 15-18M Ω;
C, step B gained material is shattered into activated aluminum powder fine particle through the cooling rotary plate of high speed rotating;
D, step C gained activated aluminum powder fine particle put into hydrolytic reaction pot hydrolysis and generate aluminium hydroxide, then centrifuge dehydration, microwave drying, comminution by gas stream;
E, step D gained material is warming up to 1150-1200 DEG C with the speed of 5 DEG C/min in calcining furnace, is then incubated 3.5-4h, obtains stable alumina powder;
F, by the briquetting press compression moulding of the alumina powder of step e gained, obtaining density is 1.8-2.0g/cm
3aluminum oxide biscuit, during compacting, pressure is 60-70MPa, then uses high temperature sintering furnace at 1650-1700 DEG C, biscuit is sintered to density and is greater than 3.7g/cm
3, to obtain final product;
In step C, the cooling cone dish rotating speed of high speed rotating is 2500-2900r/min, and the fine grain particle diameter of gained activated aluminum powder is 0.5-2 micron;
In step D, during hydrolysis, the quality proportioning of activated aluminum powder fine particle and high purity water is 1:3, adopts batch type during hydrolysis;
In step D, centrifuge dehydration by aluminum hydroxide solution more than 70% moisture filter, the aluminium hydroxide slurry obtained is trapped on the above filter cloth of 10000 order;
In step D, microwave drying is: be laid on the guipure of microwave dryer by gained aluminium hydroxide slurry, guipure is tetrafluoro material, microwave dryer Fen Liang district heats, and temperature is followed successively by 100 DEG C and 150 DEG C, and two zone lengths are followed successively by 3.5m and 2.3m, material runs with the speed that 0.5m/min is adjustable, material moves to exit, pulverizes through nylon roller, obtains dry aluminium hydroxide;
In step D, comminution by gas stream is: utilize micronizer mill, under the air pressure of 3MPa, is pulverized by the aluminium hydroxide pulverized, obtains the aluminium hydroxide powder that granularity is below 2um.
2. the preparation method of high-purity alpha-alumina as claimed in claim 1, it is characterized in that: in steps A, high-purity aluminium ingot material purity is greater than 99.9992%.
3. the preparation method of high-purity alpha-alumina as claimed in claim 1 or 2, is characterized in that: in steps A, vacuumizes, is then filled with high pure nitrogen continuously, until atomization terminates rear stopping be filled with nitrogen before high-purity aluminium ingot fusing to smelting furnace.
4. the preparation method of high-purity alpha-alumina as claimed in claim 1 or 2, it is characterized in that: in step D, hydrolytic reaction pot is made up of polypropylene material.
5. the preparation method of high-purity alpha-alumina as claimed in claim 1 or 2, it is characterized in that: step D gained material is contained into 99 porcelain dishes, in calcining furnace, be warming up to 1150-1200 DEG C with the speed of 5 DEG C/min, be then incubated 3.5-4h, obtain stable alumina powder; In step F, compression moulding is pressed down by the ceramic die of the alumina powder briquetting press of step e gained, and pressure is 60-70MPa, then full extruding dies, and obtaining density is 1.8-2.0g/cm
3aluminum oxide biscuit; In step F, the liner of sintering oven is alumina ceramic material, heating unit is Si-Mo rod, if the first baker more than one week of new sintering oven, be warmed up to 1650-1700 DEG C again to make impurity volatilization in furnace lining, the aluminum oxide of compression moulding bulk loaded in ceramic crucible after baker, be then placed on ceramic burning-resisting board advanced in high temperature sintering furnace by push rod and sinter, the temperature rise rate of sintering is 5 DEG C/min.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410626394.1A CN104386723B (en) | 2014-11-07 | 2014-11-07 | A kind of preparation method of high-purity alpha-alumina |
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|---|---|---|---|
| CN201410626394.1A CN104386723B (en) | 2014-11-07 | 2014-11-07 | A kind of preparation method of high-purity alpha-alumina |
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| CN104386723A CN104386723A (en) | 2015-03-04 |
| CN104386723B true CN104386723B (en) | 2016-03-02 |
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| CN105345018A (en) * | 2015-10-13 | 2016-02-24 | 刘冠华 | Preparation method for micron-size activated aluminum powder and aluminum powder |
| WO2017128171A1 (en) * | 2016-01-28 | 2017-08-03 | 深圳市商德先进陶瓷股份有限公司 | Plasma etching resistant ceramic body and manufacturing method thereof, and plasma etching device |
| CN106277003A (en) * | 2016-07-29 | 2017-01-04 | 刘冠华 | A kind of preparation method of high pure and ultra-fine nano-aluminum hydroxide |
| CN107337223B (en) * | 2017-08-04 | 2019-04-30 | 大连交通大学 | The water quenching preparation process of high purity aluminium oxide particle |
| CN114477969A (en) * | 2022-03-11 | 2022-05-13 | 贵州宇光鸿宇电气照明科技有限公司 | Preparation method of high-purity superfine alumina for ceramic tube |
| CN114477253A (en) * | 2022-03-15 | 2022-05-13 | 青海万加环保新材料有限公司 | Method for producing high-purity boehmite by hydrothermal method |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4615875A (en) * | 1986-02-03 | 1986-10-07 | Allied Corporation | Process for preparing high purity alpha-alumina |
| CN1394807A (en) * | 2002-07-09 | 2003-02-05 | 刘明 | Preparation method of high-purity superfine alumina powder body |
| CN101362604A (en) * | 2007-08-11 | 2009-02-11 | 陈勇 | High purity alumina powder preparation method |
| CN102093039A (en) * | 2011-01-12 | 2011-06-15 | 宁波韵升股份有限公司 | High-intensity alumina ceramic material and low temperature sintering method thereof |
| CN103043692A (en) * | 2012-12-27 | 2013-04-17 | 西安迈克森新材料有限公司 | Preparation method for high-purity aluminum oxide powder material |
| CN103787395A (en) * | 2014-01-21 | 2014-05-14 | 江苏大学 | Method for preparing micron-sized ultra-high-purity aluminum oxide powder by virtue of full-process regulation control |
-
2014
- 2014-11-07 CN CN201410626394.1A patent/CN104386723B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4615875A (en) * | 1986-02-03 | 1986-10-07 | Allied Corporation | Process for preparing high purity alpha-alumina |
| CN1394807A (en) * | 2002-07-09 | 2003-02-05 | 刘明 | Preparation method of high-purity superfine alumina powder body |
| CN101362604A (en) * | 2007-08-11 | 2009-02-11 | 陈勇 | High purity alumina powder preparation method |
| CN102093039A (en) * | 2011-01-12 | 2011-06-15 | 宁波韵升股份有限公司 | High-intensity alumina ceramic material and low temperature sintering method thereof |
| CN103043692A (en) * | 2012-12-27 | 2013-04-17 | 西安迈克森新材料有限公司 | Preparation method for high-purity aluminum oxide powder material |
| CN103787395A (en) * | 2014-01-21 | 2014-05-14 | 江苏大学 | Method for preparing micron-sized ultra-high-purity aluminum oxide powder by virtue of full-process regulation control |
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