阅读说明：本技术 一种低钠球形纳米α-氧化铝粉体的制备方法 (A kind of preparation method of low sodium ball shaped nano alpha-alumina powder ) 是由 李冬云 申亚强 孙一鸣 徐扬 葛洪良 于 2019-09-19 设计创作，主要内容包括：本发明公开了一种低钠球形纳米α-氧化铝粉体的制备方法,该方法是以廉价的工业氢氧化铝为原料；经过研磨、除钠、水洗、固液分离以及烘干等工艺过程,得到低钠氧化铝前驱体；然后将形貌诱导剂加入氧化铝前驱体中,经机械搅拌,得到混合均匀的复合粉体；将复合粉体放入马弗炉中,经烧结得到高纯球形纳米氧化铝。本发明方法所制备的低钠球形纳米氧化铝粉体的氧化钠含量为0.01～0.05％,α-Al<Sub>2</Sub>O<Sub>3</Sub>为95～99％,平均粒径D<Sub>50</Sub>为100～500nm,颗粒形貌为球形,可以满足高性能陶瓷、透明陶瓷、锂电池隔膜材料、人造宝石和精密抛光材料以及半导体材料等特殊应用。该制备方法具有原料来源广泛,设备和生产工艺简单,生产成本低,可实现工业化生产以及环境友好等特点。(The invention discloses a kind of preparation method of low sodium ball shaped nano alpha-alumina powder, this method is using cheap industrial aluminium hydroxide as raw material；By grinding, the technical process such as sodium, washing, separation of solid and liquid and drying are removed, obtain low sodium alumina presoma；Then shape inducer is added in alumina precursor, through mechanical stirring, obtains uniformly mixed composite granule；Composite granule is put into Muffle furnace, obtains high-purity spherical nano aluminium oxide through sintering.The sodium oxide content of low sodium ball shaped nano alumina powder prepared by the method for the present invention is 0.01~0.05%, α-Al 2 O 3 It is 95~99%, average grain diameter D 50 For 100~500nm, granule-morphology is spherical shape, can satisfy high-performance ceramic, crystalline ceramics, lithium battery diaphragm material, synthetic cut stone and the special applications such as precise polishing materials and semiconductor material.The preparation method have raw material sources it is extensive, equipment and simple production process, production cost it is low, it can be achieved that industrialized production and it is environmental-friendly the features such as.)

1. a kind of preparation method of low sodium ball shaped nano alpha-alumina powder, it is characterised in that: using industrial aluminium hydroxide as raw material； Industrial aluminium hydroxide, dispersing agent and deionized water are hybridly prepared into slurry first；By grinding, remove sodium, separation of solid and liquid, water It washes, be separated by solid-liquid separation and stoving process, obtain low sodium alumina presoma；Then before low sodium alumina being added in shape inducer It drives in body, it is agitated, obtain uniformly mixed composite granule；Low sodium ball shaped nano-alpha-oxygen finally is made through sintering in composite granule Change aluminium powder body.

2. the preparation method of low sodium ball shaped nano alpha-alumina powder according to claim 1, which is characterized in that described Industrial aluminium hydroxide powder is Bayer process preparation, and the primary particle size of powder is 1~500 μm, sodium oxide content is 0.2~ 0.5wt%.

3. the preparation method of low sodium ball shaped nano alpha-alumina powder according to claim 1, which is characterized in that described Dispersing agent is one of polyethylene glycol, triethanolamine, polyacrylamide, polyethyleneimine or two kinds, the additive amount of dispersing agent For 0.2~2wt% of industrial aluminium hydroxide.

4. the preparation method of low sodium ball shaped nano alpha-alumina powder according to claim 1, which is characterized in that described The content of industrial aluminium hydroxide is 10~40wt% in slurry.

5. the preparation method of low sodium ball shaped nano alpha-alumina powder according to claim 1, which is characterized in that described Grinding is ground using sand mill, and abrasive media is zirconia ball or alumina balls, and the diameter of medium ball is 2~0.5 μm, is ground Time consuming is 0.5~5h.

6. the preparation method of low sodium ball shaped nano alpha-alumina powder according to claim 1, which is characterized in that described Except the sodium removing agent that sodium is selected is acetic acid, the additive amount of acetic acid is that the pH value of adjusting slurry is 4~7.

7. the preparation method of low sodium ball shaped nano alpha-alumina powder according to claim 1, which is characterized in that described It is separated by solid-liquid separation to be centrifugated, centrifugal speed is 2000~10000 turns/min, and centrifugation time is 10~60min.

8. the preparation method of low sodium ball shaped nano alpha-alumina powder according to claim 1, which is characterized in that described Washing uses temperature for 50~100 DEG C of deionized water, and ratio of water to material is 5:1~20:1, and washing times are 2~4 times；The baking The dry low temperature baking oven used or continuous tunnel furnace drying, drying temperature are 110~150 DEG C, drying time is 8~for 24 hours.

9. the preparation method of low sodium ball shaped nano alpha-alumina powder according to claim 1, which is characterized in that described Shape inducer is boric acid, and additional amount is 0.2~0.8wt% times of low sodium alumina presoma；The stirring is stirred for dry method It mixes, using one of dry method mechanical stirring, dry ball milling or dry method planetary mills, mixing time is 0.5~2h.

10. the preparation method of low sodium ball shaped nano alpha-alumina powder according to claim 1, which is characterized in that described Sintering be to be carried out in Muffle furnace, sintering temperature be 1150~1250 DEG C, the time be 30~120min, heating rate be 5~ 20℃/min。

Technical field

The present invention relates to a kind of nano alumina powder jointed preparation methods, and in particular to a kind of low sodium ball shaped nano alpha-oxidation Aluminium raw powder's production technology.

Background technique

The molecular formula of aluminium oxide is Al₂O₃, it is divided into a variety of crystal forms such as α, γ, β, ρ, κ, δ, θ according to its crystal structure, wherein α-Al₂O₃It is high-temperature stable crystal form, it is a series of to have that fusing point is high, hardness is big, intensity is high, wearability is good, acid-alkali-corrosive-resisting is good etc. Excellent performance is widely used in the industries such as refractory material, ceramics, abrasive material and petrochemical industry.With the continuous development of science and technology, Aluminium oxide becomes one of a kind of material with fastest developing speed, and high-purity, nano-grade size and spherical morphology have expanded aluminium oxide significantly Purposes, can be used to prepare fine ceramics, crystalline ceramics, lithium battery diaphragm material, high-performance ceramic, synthetic cut stone and accurate throw The products such as luminescent material and semiconductor material.

Ball-aluminium oxide mainly uses sol-gal process, rolls the preparation of the methods of the method for forming and oil (ammonia) column method at present.It is molten Sol-gel prepares nano aluminium oxide often using rafifinal, aluminium isopropoxide or boehmite as raw material, by hydrolytie polycondensation, cohesion.It should The disadvantages of kind of method is there are expensive starting materials, production technology is complicated, high production cost, and production capacity is small.Rolling the method for forming is to prepare oxidation One of alumina supporter and adsorbent method are usually used in the molding of hydraulicity material, but the method is poor to adaptability to raw material, product surface Smoothness is poor, and operating environment is poor, and due to the product particle degree size unevenness of preparation to which application is limited.Oily (ammonia) column method is real What is used on border is also that collosol and gel principle is formed, but since its molding need to carry out under higher temperature conditions, energy consumption is high, And the shortcomings that there are curing rates is slow, low efficiency, therefore it is unfavorable for industrialized production.

Patent CN104418371A discloses a kind of oily (ammonia) column method and prepares ball-aluminium oxide, key step include: with Boehmite powder is raw material, mixed acid solution is added in the feed Aluminum sol is made, then Aluminum sol is instilled in oil ammonia column Then balling-up carries out roasting obtained ball-aluminium oxide.The ball-aluminium oxide of this method preparation has low-density, macropore appearance, surface The characteristics of smooth, moderate strength；But the method energy consumption is higher, and for oil ammonia column, colloidal sol is being formed by pin hole when dripping ball Droplet size have difference, cause bead particle size uneven；And the problem of droplet-shaped can be presented in drop when due to drop ball, from And greatly reduce the ratio of briquetting of product；In process of production, due to the presence of ammonia, environment can be caused seriously to pollute.

In order to solve energy consumption and pollution problem during oily (ammonia) column method prepares ball-aluminium oxide, patent CN104353502A discloses a kind of preparation method of macropore appearance ball-aluminium oxide, and key step includes: by aluminium glue, deionization Water, alginate solution are uniformly mixed, and add boehmite or alumina powder, and suspension slurry is made in stirring；It is starched being suspended Material, which is added dropwise in multivalent metal cation solution, forms spherical composite gel particle；Gel particle is taken out, is dried, roasts To ball-aluminium oxide product.The ball-aluminium oxide of the method preparation has Kong Rong great, intensity high and distribution collects medium advantage.But it deposits Long preparation period, production capacity is low, at high cost the disadvantages of, limit the industrialization of the technique；And due to preparing through the technique Aluminium oxide is mostly γ phase alumina, the mechanical strength of product is lower, therefore product is of limited application.

Patent CN103864123A discloses a kind of water column forming method of ball-aluminium oxide, key step include: by Boehmite is mixed with soluble alginate, slurry is made, then slurry is added dropwise in multivalent metal cation salting liquid, Gelled pill is formed, immersion treatment is then carried out to gelled pill using acid solution, then by gelled pill in alkalescent reaming It is impregnated in agent aqueous solution, by drying, roasts obtained ball-aluminium oxide.The method is the optimization technique of oily (ammonia) column method, due to It is used forms under water body series normal temperature, therefore is efficient one kind, low cost, low energy consumption, environmentally protective ball-aluminium oxide preparation Method.But the complex process, product prepare the high requirements on the equipment, prepared Alumina spheres partial size in 2mm or so, and The patent is without product pattern map.

Patent CN105289756A discloses the technique that a kind of sol-gal process prepares ball-aluminium oxide, and step includes: Gellan gum, alumina precursor are mixed with deionized water, and make feed liquid homogeneous, suspension slurry is made；Suspension slurry is added Dripping is carried out in pill dripping machine, and gel beads are formed by curing in organic phase；Again by gel beads with metal cation curing agent into one Step enhancing curing process；Product is made in dry, roasting.Method molding big, good sphericity, Kong Rong great, preparation with product strength The advantages such as process is pollution-free, and operating procedure simple possible, industrialized production easy to accomplish.But there is also costs for this technique High, the problems such as production capacity is low.

Patent CN106892648A discloses a kind of preparation method of ball-aluminium oxide, and key step includes: thin to intend Diaspore powder is raw material, is mixed with shaping assistant, strip plastic is made；Then it places it in real in balling head Existing broken strip and rolling are granulated, and spray into the wetting agent of misty liquid droplets, and the smooth spheric granules in surface is made；Again by spherical shape obtained Particle is in 500~1300 DEG C of roasting temperatures, and finally obtained aluminium oxide is spherical.The method solves the powder rolled in granulation process Dirt pollution problem, obtained aluminium oxide ball-type degree is high, surface smooth abrasion-proof, and preparation cost is low, is provided simultaneously with mechanical strong High advantage is spent, but the aluminium oxide spheric granules prepared is larger and granularity is uneven, a diameter of 0.3~3mm.

Patent CN107176617A discloses a kind of preparation method of novel ball aluminium oxide, step specifically include that by Mixing aluminium salt is uniformly mixed with polyethylene glycol, sodium salt solution, precipitating reagent, and precursor solution is obtained after mixed solution is ultrasonically treated； Then presoma is dried, high-temperature roasting obtains alumina powder, the metal salt for obtaining alumina powder and multiple element is mixed It closes；Mixed powder is handled using glow discharge plasma technology, the ball-aluminium oxide is made.Using this technique Can prepare specific surface area is larger, pore-size distribution preferably, good dispersion, homogeneous grain diameter, spheric active aluminium oxide resistant to high temperature；Its Disadvantage is that at high cost, sample purity is low, sample crystallization situation is poor, long preparation period is unfavorable for industrializing.

Summary of the invention

The present invention provides a kind of low sodium ball shaped nano-alpha-Al₂O₃Powder preparation method is solved and is produced into the prior art The problems such as this height, production technology are complicated, sodium content is high, particle size and pattern are difficult to control.

The present invention is implemented with the following technical solutions:

A kind of preparation method of low sodium ball shaped nano alpha-alumina powder, using industrial aluminium hydroxide as raw material；First by work Industry aluminium hydroxide, dispersing agent and deionized water are hybridly prepared into slurry；By grinding, except sodium, separation of solid and liquid, washing, solid-liquid point From and stoving process, obtain low sodium alumina presoma；Then shape inducer is added in low sodium alumina presoma, warp Stirring, obtains uniformly mixed composite granule；Low sodium ball shaped nano alpha-alumina powder finally is made through sintering in composite granule.

In above-mentioned technical proposal, further, the industrial aluminium hydroxide powder be Bayer process preparation, powder it is initial Granular size is 1~500 μm, and sodium oxide content is 0.2~0.5wt%.

Further, the dispersing agent is polyethylene glycol, triethanolamine, polyacrylamide, one in polyethyleneimine Kind or two kinds, the additive amount of dispersing agent is 0.2~2wt% of industrial aluminium hydroxide.

Further, the content of industrial aluminium hydroxide is 10~40wt% in the slurry.

Further, the grinding is ground using sand mill, and abrasive media is zirconia ball or alumina balls, is situated between The diameter of matter ball is 2~0.5 μm, and milling time is 0.5~5h.

Further, the sodium removing agent selected except sodium is acetic acid, and the additive amount of acetic acid is that the pH value of adjusting slurry is 4 ~7.

Further, the separation of solid and liquid is centrifuge separation, and centrifugal speed is 2000~10000 turns/min, when centrifugation Between be 10~60min.

Further, the washing uses temperature for 50~100 DEG C of deionized water, and ratio of water to material is 5:1~20:1, water Washing number is 2~4 times；The low temperature baking oven or continuous tunnel furnace drying that the drying uses, drying temperature is 110~150 DEG C, drying Time be 8~for 24 hours.

Further, the shape inducer be boric acid, additional amount be low sodium alumina presoma 0.2~ 0.8wt% times；The stirring is dry stirring, using one of dry method mechanical stirring, dry ball milling or dry method planetary mills, Mixing time is 0.5~2h.

Further, the sintering is carried out in Muffle furnace, sintering temperature be 1150~1250 DEG C, the time be 30~ 120min, heating rate are 5~20 DEG C/min.

Using the Na of low sodium ball shaped nano alumina powder prepared by the method for the present invention₂O content be 0.01~ 0.05wt%, α-Al₂O₃Content is 95~99wt%, average grain diameter D₅₀For 100~500nm, granule-morphology is spherical shape.

Compared with the prior art, the present invention has the following beneficial effects:

(1) using cheap industrial aluminium hydroxide as raw material, by the fine grinding of nano-level grinder, aquation, except sodium with And the booster action of shape inducer, prepare low sodium ball shaped nano alpha alumina powder (Na₂O content be 0.01~ 0.05%).This method has raw material sources extensive, equipment and simple production process, and production cost is low, it can be achieved that industrialized production And the features such as environmental-friendly.

(2) the low sodium ball shaped nano alumina powder prepared by the present invention have sodium content it is low, it is uniform in size, having a size of receiving The advantages that meter level, crystal phase are α phase, and granule-morphology is spherical, can satisfy high-performance ceramic, crystalline ceramics, lithium battery diaphragm material Material, synthetic cut stone and the special applications such as precise polishing materials and semiconductor material.

(3) the method for the present invention can significantly reduce remaining in ball shaped nano alpha alumina powder using acetic acid as sodium removing agent Sodium content；Using boric acid as shape inducer, the pattern for the nanometer alpha alumina powder being prepared is spherical shape.

Detailed description of the invention

Fig. 1 is aluminium oxide scanning electron microscope (SEM) photograph prepared by embodiment 1；

Fig. 2 is the X-ray diffractogram of aluminium oxide prepared by embodiment 1；

Fig. 3 is the scanning electron microscope (SEM) photograph of aluminium oxide prepared by embodiment 2；

Fig. 4 is the X-ray diffractogram of aluminium oxide prepared by embodiment 2；

Fig. 5 is the scanning electron microscope (SEM) photograph of aluminium oxide prepared by embodiment 3；

Fig. 6 is the X-ray diffractogram of aluminium oxide prepared by embodiment 3.

Specific embodiment

The invention will be further described in the following with reference to the drawings and specific embodiments.

A kind of low sodium ball shaped nano-alpha-Al₂O₃Raw powder's production technology includes the following steps:

(1) industrial aluminium hydroxide, dispersing agent and deionized water are mixed to the hydrogen for being made into that solid content is 10~40wt% Alumina slurry is ground in sand mill, and abrasive media is zirconia ball or alumina balls, and the diameter of ball is 2~0.5 μ M, milling time are 0.5~5h, obtain the alumina precursor slurry of refinement；

(2) alumina precursor slurry obtained in step (1) is stirred in 50~100 DEG C of 20~60min of stirred in water bath It is 4~7 that sodium removing agent acetic acid is added while mixing and adjusts the pH value of slurry, obtains the alumina precursor slurry of non-alkaline；

(3) alumina precursor slurry obtained in step (2) is separated by solid-liquid separation using supercentrifuge, consolidate State alumina precursor.Centrifugal speed is 2000~10000 turns/min, and centrifugation time is 10~60min；

(4) solid oxide aluminium presoma obtained in step (3) is obtained into low sodium oxygen by 2~4 washings, separation of solid and liquid Change aluminium presoma.The temperature of deionized water used is 50~100 DEG C when washing, and ratio of water to material is 5:1~20:1.

(5) by low sodium alumina presoma obtained in step (4) dry 8 in 110~150 DEG C of baking ovens~for 24 hours；

(6) induction of 0.2~0.8wt% pattern will be added in the low sodium alumina presoma of drying obtained in step (5) The composite granule for being made uniformly mixed is mixed through 0.5~2h in agent boric acid；

(7) composite granule obtained in step (6) is placed in batch-type furnace to be sintered and obtains high-purity spherical nano oxidation Aluminium powder body.Sintering temperature is 1150~1250 DEG C, and soaking time is 60min~120min, and heating rate is 5~20 DEG C/min, The type of cooling is to cool to room temperature with the furnace.