JPH04160007A - Continuous production of spherical superfine particles - Google Patents
Continuous production of spherical superfine particlesInfo
- Publication number
- JPH04160007A JPH04160007A JP2284167A JP28416790A JPH04160007A JP H04160007 A JPH04160007 A JP H04160007A JP 2284167 A JP2284167 A JP 2284167A JP 28416790 A JP28416790 A JP 28416790A JP H04160007 A JPH04160007 A JP H04160007A
- Authority
- JP
- Japan
- Prior art keywords
- alkoxide
- particles
- reaction
- nucleus
- seed
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000002245 particle Substances 0.000 title claims abstract description 69
- 238000010924 continuous production Methods 0.000 title claims description 5
- 150000004703 alkoxides Chemical class 0.000 claims abstract description 32
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 23
- 238000006243 chemical reaction Methods 0.000 claims abstract description 19
- 239000000843 powder Substances 0.000 claims abstract description 16
- 239000000919 ceramic Substances 0.000 claims abstract description 12
- 238000001035 drying Methods 0.000 claims abstract description 6
- 238000011144 upstream manufacturing Methods 0.000 claims abstract description 5
- 238000000034 method Methods 0.000 claims description 13
- 239000002994 raw material Substances 0.000 claims description 11
- 239000000126 substance Substances 0.000 claims description 8
- 238000010304 firing Methods 0.000 claims description 5
- 239000011882 ultra-fine particle Substances 0.000 claims description 4
- 238000009833 condensation Methods 0.000 abstract description 10
- 230000005494 condensation Effects 0.000 abstract description 10
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 abstract description 7
- 239000000463 material Substances 0.000 abstract description 7
- 239000000443 aerosol Substances 0.000 abstract description 4
- 229920006395 saturated elastomer Polymers 0.000 abstract description 4
- 239000000203 mixture Substances 0.000 abstract description 3
- 238000003303 reheating Methods 0.000 abstract description 3
- JPUHCPXFQIXLMW-UHFFFAOYSA-N aluminium triethoxide Chemical compound CCO[Al](OCC)OCC JPUHCPXFQIXLMW-UHFFFAOYSA-N 0.000 abstract description 2
- 239000006200 vaporizer Substances 0.000 abstract 3
- 238000001354 calcination Methods 0.000 abstract 1
- 229910052593 corundum Inorganic materials 0.000 abstract 1
- 229910001845 yogo sapphire Inorganic materials 0.000 abstract 1
- 238000009826 distribution Methods 0.000 description 17
- 239000007789 gas Substances 0.000 description 10
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 7
- 229910001873 dinitrogen Inorganic materials 0.000 description 7
- 239000007787 solid Substances 0.000 description 5
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- JMXKSZRRTHPKDL-UHFFFAOYSA-N titanium ethoxide Chemical compound [Ti+4].CC[O-].CC[O-].CC[O-].CC[O-] JMXKSZRRTHPKDL-UHFFFAOYSA-N 0.000 description 4
- 238000004458 analytical method Methods 0.000 description 3
- 239000003085 diluting agent Substances 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 230000006911 nucleation Effects 0.000 description 3
- 238000010899 nucleation Methods 0.000 description 3
- WOZZOSDBXABUFO-UHFFFAOYSA-N tri(butan-2-yloxy)alumane Chemical compound [Al+3].CCC(C)[O-].CCC(C)[O-].CCC(C)[O-] WOZZOSDBXABUFO-UHFFFAOYSA-N 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- 239000012159 carrier gas Substances 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 239000010419 fine particle Substances 0.000 description 2
- 238000006460 hydrolysis reaction Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 238000005245 sintering Methods 0.000 description 2
- 239000012798 spherical particle Substances 0.000 description 2
- 238000001089 thermophoresis Methods 0.000 description 2
- FIPWRIJSWJWJAI-UHFFFAOYSA-N Butyl carbitol 6-propylpiperonyl ether Chemical group C1=C(CCC)C(COCCOCCOCCCC)=CC2=C1OCO2 FIPWRIJSWJWJAI-UHFFFAOYSA-N 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- SMZOGRDCAXLAAR-UHFFFAOYSA-N aluminium isopropoxide Chemical compound [Al+3].CC(C)[O-].CC(C)[O-].CC(C)[O-] SMZOGRDCAXLAAR-UHFFFAOYSA-N 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 238000005229 chemical vapour deposition Methods 0.000 description 1
- 239000011246 composite particle Substances 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- KZHJGOXRZJKJNY-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Si]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O KZHJGOXRZJKJNY-UHFFFAOYSA-N 0.000 description 1
- 238000004993 emission spectroscopy Methods 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 239000001307 helium Substances 0.000 description 1
- 229910052734 helium Inorganic materials 0.000 description 1
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 1
- 230000003301 hydrolyzing effect Effects 0.000 description 1
- 150000004679 hydroxides Chemical class 0.000 description 1
- 239000003701 inert diluent Substances 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 229910052863 mullite Inorganic materials 0.000 description 1
- WHOPEPSOPUIRQQ-UHFFFAOYSA-N oxoaluminum Chemical compound O1[Al]O[Al]1 WHOPEPSOPUIRQQ-UHFFFAOYSA-N 0.000 description 1
- 229960005235 piperonyl butoxide Drugs 0.000 description 1
- 150000003609 titanium compounds Chemical class 0.000 description 1
- 239000004408 titanium dioxide Substances 0.000 description 1
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 1
- VXUYXOFXAQZZMF-UHFFFAOYSA-N titanium(IV) isopropoxide Chemical compound CC(C)O[Ti](OC(C)C)(OC(C)C)OC(C)C VXUYXOFXAQZZMF-UHFFFAOYSA-N 0.000 description 1
- 238000004448 titration Methods 0.000 description 1
Landscapes
- Compositions Of Oxide Ceramics (AREA)
- Oxygen, Ozone, And Oxides In General (AREA)
- Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
新材料開発の分野で、超微粉の純度・粒子形状・粒度分
布等を制御することにより、これを焼結または分散して
えられる材料に、多様な新しい機能を付与することが期
待されている。この中で、サブミクロンサイズで粒度分
布が狭く、かつ球状粒子のセラミック微粉は、焼結原料
粉や充填材、研摩材、標準粒子等として用途の拡大が期
待される。[Detailed description of the invention] [Field of industrial application] In the field of new material development, by controlling the purity, particle shape, particle size distribution, etc. of ultrafine powder, it can be made into a material obtained by sintering or dispersing it. , is expected to add a variety of new functions. Among these, ceramic fine powder with submicron size, narrow particle size distribution, and spherical particles is expected to find expanded applications as sintering raw material powder, filler, abrasive, standard particles, etc.
本発明はこの粒径の整った球形超微粒子の連続製造方法
に関するものである。The present invention relates to a method for continuously producing ultrafine spherical particles of uniform particle size.
従来、セラミック微粉の多くは液滴を経由しない直接Ｃ
ＶＤによって製造されていた。液滴を経由する製造方法
も利用されているが、その場合、−船釣に種粒子は用い
られていなかった。ところで、チタン（ＩＶ）エトキシ
ドなどの４価の液状チタン化合物の液滴を加水分解して
球形の二酸化チタン粒子を製造する際に、ＡｇＣ１！、
を種粒子に用いる方法が知られている。（Ｍ、Ｖｉｓｃ
ａ ｅｔ ａｌ、、 Ｊｏｕｒｎａｌｏｆ Ｃｏ１１ｏ
ｉｄ ａｎｄ Ｉｎｔｅｒｆａｃｅ ５ｃｉｅｎｃｅ、
ｖｏｌ、 ６８＋Ｎｏ、２． Ｐ３０Ｂ〜３１９．１
９７９）。また、アルミニウム第二ブトキシド蒸気を凝
縮させて液滴を形成し、続いて液滴と水蒸気との化学反
応を乱流系で行なわせることによるサブミクロン単位の
アルミナ粉を製造する方法も知られている（Ｔ、Ｔ、
Ｋｏｄａｓら、Ｐｏｗｄｅｒ Ｔｅｃｈｎｏｌｏｇｙ、
５０巻、４７〜５３頁、１９８７年）。Conventionally, most of the ceramic fine powders were produced by direct C without going through droplets.
Manufactured by VD. Production methods via droplets have also been used, but in that case - seed particles were not used in boat fishing. By the way, when producing spherical titanium dioxide particles by hydrolyzing droplets of a tetravalent liquid titanium compound such as titanium (IV) ethoxide, AgC1! ,
A method is known in which the particle is used as a seed particle. (M, Visc.
a et al,, Journalof Co11o
ID and Interface 5science,
vol, 68+No, 2. P30B~319.1
979). It is also known to produce submicron-sized alumina powder by condensing aluminum sec-butoxide vapor to form droplets, followed by a chemical reaction between the droplets and water vapor in a turbulent flow system. There is (T, T,
Kodas et al., Powder Technology;
50, pp. 47-53, 1987).
このなかでは乱流系と層流系が検討され、さらに凝縮前
に種粒子を加えることによって凝縮器壁面での液滴の凝
縮を減少させるとともに粒度分布もかなり狭まることが
報告されている。In this study, turbulent flow systems and laminar flow systems have been investigated, and it has been reported that adding seed particles before condensation reduces the condensation of droplets on the condenser wall and considerably narrows the particle size distribution.
液滴を経由しない直接ＣＶＤは粒度分布が広いばかりで
なく粒形も不揃いであった。液滴を経由する方法の場合
には球形微粒子が得られるが粒度分布が極めて広く、ま
た生成効率にも問題があった。ＡｇＣｊ！等の種粒子を
用いる方法は粒度分布の狭い球形微粒子が得られるが純
度が低下するという問題があった。Ｋ ｏｄａｓらは同
一物質を種粒子として用いる方法を開示しているが粒度
分布が広いという問題があった。Direct CVD without using droplets resulted in not only a wide particle size distribution but also irregular particle shapes. In the case of the method using droplets, spherical fine particles can be obtained, but the particle size distribution is extremely wide, and there are also problems in production efficiency. AgCj! Although the method using seed particles such as the above produces spherical fine particles with a narrow particle size distribution, there is a problem in that the purity decreases. Kodas et al. have disclosed a method using the same material as seed particles, but there was a problem that the particle size distribution was wide.
本発明は上記の課題を解決して、粒度分布が極めて狭く
、かつ高純度のセラミック微粉を製造する手段を提供す
ることを目的としている。An object of the present invention is to solve the above-mentioned problems and provide a means for producing ceramic fine powder having an extremely narrow particle size distribution and high purity.
本発明は上記目的を達成した球形超微粒子の連続製造方
法を提供するものであり、アルコキシドと水蒸気を反応
させてセラミック微粉を得る液滴 ＣＶＤにおいて
、液滴の核となる種粒子を導入するに際し、主反応と同
一系統の上流で原料アルコキシドの一部を消費する反応
操作により目的セラミック微粉と同一物質又は乾燥もし
くは焼成によって同一物質となりうる種粒子を作製する
ことを特徴としている。The present invention provides a method for continuous production of spherical ultrafine particles that achieves the above object, and is a droplet CVD method for producing fine ceramic powder by reacting an alkoxide with water vapor. This method is characterized by producing seed particles that are the same substance as the target ceramic fine powder, or that can become the same substance by drying or firing, by a reaction operation that consumes a part of the raw material alkoxide upstream of the same system as the main reaction.
球形超微粒子はセラミックであり、例えばＡｌ２Ｏ２、
Ｔ ｉ Ｏ！、Ｓ ｉ Ｏｚ、Ｚ ｒ Ｏを等の酸化物
、ＢａＴｉｏ３等の複合酸化物、ムライト（３Ａ １
ｔ Ｏｓ・２Ｓｉｆｔ）等の複合粒子等である。平均粒
径は０．０５〜５ｐ程度、好ましくは０．０５〜０．３
−程度であり、分布は幾何標準偏差で１．２〜１．４、
特に１．２５〜１．３５程度である。The spherical ultrafine particles are ceramics, such as Al2O2,
TiO! , S i Oz, Z r O, etc., complex oxides such as BaTio3, mullite (3A 1
These are composite particles such as tOs・2Sift). Average particle size is about 0.05 to 5p, preferably 0.05 to 0.3
- degree, and the distribution has a geometric standard deviation of 1.2 to 1.4,
In particular, it is about 1.25 to 1.35.
これらはアルコキシドと水蒸気の反応によって生成させ
る。アルコキシドは反応時に液状のものであり、例えば
アルミナを製造する場合にはアルミニウムエトキシド、
アルミニウムイソプロポキシド、アルミニウムブトキシ
ド等を利用することができ、チタニアの場合にはチタン
（ＩＶ）エトキシド、チタン（ＩＶ）イソプロポキシド
等を利用することができる。These are produced by the reaction of alkoxides and water vapor. Alkoxides are liquid during reaction; for example, when producing alumina, aluminum ethoxide,
Aluminum isopropoxide, aluminum butoxide, etc. can be used, and in the case of titania, titanium (IV) ethoxide, titanium (IV) isopropoxide, etc. can be used.
種粒子は目的物であるセラミックと同一物質又は乾燥も
しくは焼成等によって同一物質となりうるものである。The seed particles are the same material as the target ceramic, or can be made into the same material by drying, firing, etc.
乾燥もしくは焼成によって同一物質となりうるものとは
、例えば水酸化物等である。Examples of substances that can be converted into the same substance by drying or firing include hydroxides.
アルコキシドと水蒸気の反応は５０〜１３０°Ｃ程度で
行なわせればよく、圧力は加圧、減圧、常圧のいずれで
あってもよく、例えば７８０〜８５０Ｔｏｒｒ程度でよ
い。アルコキシドと水蒸気は並流で接触させてもよく、
クロスフローで接触させてもよい。アルコキシドと水蒸
気の混合割合は水蒸気を過剰にするのがよ（、アルコキ
シドとの反応に必要なモル数の３〜５倍程度が適当であ
る。適した濃度として、反応を制御するために反応に不
活性の希釈ガスを用いることが好ましい。この希釈ガス
は搬送ガスとしても機能するものであり窒素ガス、アル
ゴンガス、ヘリウムガス等を使用できるが、窒素ガスが
安価で入手が容易な点で好ましい。希釈倍率はモル比で
アルコキシドは５００〜２０００倍程度、水蒸気は５〜
３０倍程度が好ましい。The reaction between the alkoxide and water vapor may be carried out at about 50 to 130°C, and the pressure may be increased, reduced, or normal pressure, for example, about 780 to 850 Torr. The alkoxide and water vapor may be brought into contact in parallel flow,
Contact may be made through cross flow. The mixing ratio of alkoxide and water vapor should be such that the amount of water vapor is in excess (approximately 3 to 5 times the number of moles required for the reaction with the alkoxide. It is preferable to use an inert diluent gas.This diluent gas also functions as a carrier gas, and nitrogen gas, argon gas, helium gas, etc. can be used, but nitrogen gas is preferable because it is cheap and easily available. The dilution ratio is about 500 to 2000 times for alkoxide and 5 to 2000 times for water vapor in terms of molar ratio.
About 30 times is preferable.
本発明はこのような方法において、液滴の核となるアル
コキシドと水蒸気を反応させてセラミック微粉を得る液
滴ＣＶＤにおいて、液滴の核となる種粒子を導入するに
際し、主反応と同一系統の上流で原料アルコキシドの一
部を消費する反応操作により目的セラミック微粉と同一
物質又は乾燥もしくは焼成によって同一物質となりうる
種粒子を作製するところに特徴がある。In this method, the present invention uses droplet CVD in which a fine ceramic powder is obtained by reacting an alkoxide, which serves as the nucleus of a droplet, with water vapor. The method is characterized in that a reaction operation that consumes a portion of the raw material alkoxide upstream produces seed particles that are the same substance as the target ceramic fine powder, or that can become the same substance by drying or firing.
主反応と同一系統の上流で原料アルコキシドの一部を消
費する反応とは具体的には原料アルコキシドの流れに水
蒸気の一部を吹込むことによって行なわれる。水蒸気の
混合量は種粒子を生成させる量であり、原料アルコキシ
ドとの反応に必要な理論量の２〜８％程度、特に２．５
〜５％程度が適当である。この水蒸気も適した濃度で供
給するために希釈ガスで希釈して混合するのがよい。希
釈ガスは前記と同様のものが使用される。核となる種粒
子の生成はアルコキシドが凝縮しない温度で行なわせ、
例えば１５０〜１８０℃程度が適当である。Specifically, the reaction that consumes a portion of the raw material alkoxide upstream in the same system as the main reaction is carried out by blowing a portion of steam into the flow of the raw material alkoxide. The amount of water vapor mixed is the amount that generates seed particles, and is about 2 to 8% of the theoretical amount required for reaction with the raw material alkoxide, especially 2.5%.
Approximately 5% is appropriate. In order to supply this water vapor at an appropriate concentration, it is preferable to dilute it with a diluent gas and mix it. The same diluent gas as described above is used. The seed particles that serve as the nucleus are generated at a temperature at which the alkoxide does not condense.
For example, a temperature of about 150 to 180°C is appropriate.
圧力は加圧、減圧、常圧のいずれでもよく、例えば７８
０〜８５０Ｔｏｒｒ程度でよい。The pressure may be increased pressure, reduced pressure, or normal pressure, for example 78
It may be about 0 to 850 Torr.
種粒子形成後は、原料アルコキシドの流れを冷却してア
ルコキシド蒸気を種粒子上に凝縮させる。After seed particles are formed, the feed alkoxide stream is cooled to condense alkoxide vapor onto the seed particles.
凝縮器温度が低すぎると、シード粒子が熱泳動により壁
面に捕捉されやすくなり、無核凝縮核生成が起こりやす
くなる。また、高すぎると凝縮が不充分になる。そこで
９５％以上のアルコキシド蒸気が凝縮する温度が適当で
ある。If the condenser temperature is too low, seed particles are likely to be trapped on the wall surface due to thermophoresis, making it easier for nuclear-free condensation nucleation to occur. Moreover, if it is too high, condensation will be insufficient. Therefore, a temperature at which 95% or more of the alkoxide vapor is condensed is appropriate.
凝縮後は主反応器内で前記条件で主反応を行なわせ、そ
の後はサイクロン、フィルター、静電捕集等により捕集
して乾燥し、必要により焼成すればよい。After condensation, the main reaction is carried out in the main reactor under the above conditions, and then collected using a cyclone, filter, electrostatic collection, etc., dried, and, if necessary, calcined.
アルミニウム・トリ・セカンダリ−・ブトキシドを原料
とした場合について平均径、幾何標準偏差、個数濃度お
よび体積濃度に対する操作条件の効果を整理した例を第
４図及び第５図に示す。主反応器の温度は１００°Ｃで
ある。目印はシードのある場合であり、無印はシードの
ない場合である。FIGS. 4 and 5 show examples of the effects of operating conditions on the average diameter, geometric standard deviation, number concentration, and volume concentration when aluminum tri-secondary butoxide is used as the raw material. The temperature of the main reactor is 100°C. A mark indicates a case where there is a seed, and a mark indicates a case without a seed.
原料アルコキシド総量の３．５％がシード粒子に変換さ
れている。ここでの２因子の効果と機構を考察すると次
のようになる。すなわち、本発明の方法においてはシー
ド粒子を導入することによって、シード粒子の表面に蒸
気が凝縮・成長（不均一核生成）するので、成長速度の
粒径依存性により、粒径分布は狭く、個数濃度は高くな
る。また、凝縮器温度が低すぎると、シード粒子が熱泳
動により壁面に捕捉されやすくなり、無核凝縮核生成が
起こりやすくなる。このとき、温度差が大きいため生成
核も壁面に捕捉されやすく、蒸気濃度は低下し、また温
度分布が不均一になりやすいので、核の生成・成長が不
均一になる。この結果、粒子の径は全体に小さく、分布
は広くなり、また個数濃度は低くなる。当然、粒子体積
濃度は低く、損失が大きい。3.5% of the total raw material alkoxide is converted to seed particles. The effects and mechanisms of the two factors here are considered as follows. That is, in the method of the present invention, by introducing seed particles, vapor condenses and grows on the surface of the seed particles (heterogeneous nucleation), so the particle size distribution is narrow due to the particle size dependence of the growth rate. The number concentration becomes high. Furthermore, if the condenser temperature is too low, seed particles are likely to be captured on the wall surface due to thermophoresis, making it easy for non-nuclear condensation nucleation to occur. At this time, since the temperature difference is large, the generated nuclei are also likely to be captured on the wall surface, the vapor concentration decreases, and the temperature distribution tends to be uneven, resulting in uneven generation and growth of the nuclei. As a result, the diameter of the particles is small overall, the distribution is wide, and the number concentration is low. Naturally, the particle volume concentration is low and losses are high.
実施例１
第１図に示す装置を使用した。この装置はアルコキシド
蒸発器ｌ、核となる種粒子生成用の水蒸発器２、主反応
用水蒸発器３、核となる種粒子を生成させる核発生器４
、アルコキシド蒸気の凝縮器５．６、凝縮器間に設けら
れた再加熱部７、主反応器８、捕集器９等からなってい
る。希釈搬送ガスである窒素ガスはボンベ１０から流量
調節弁ＩＩを経てアルコキシド液又は水が入っている各
蒸発器１．２．３に送られ、そこでバブリングされる。Example 1 The apparatus shown in FIG. 1 was used. This device consists of an alkoxide evaporator 1, a water evaporator 2 for generating seed particles that will become the nucleus, a water evaporator 3 for the main reaction, and a nuclear generator 4 that generates the seed particles that will become the nucleus.
, a condenser 5.6 for alkoxide vapor, a reheating section 7 provided between the condensers, a main reactor 8, a collector 9, etc. Nitrogen gas, which is a diluted carrier gas, is sent from the cylinder 10 via a flow control valve II to each evaporator 1.2.3 containing an alkoxide liquid or water, where it is bubbled.
アルコキシド蒸発器１を出たアルコキシドを飽和状態で
含む窒素ガスと水蒸発器２を出た水蒸気を飽和状態で含
む窒素ガスは核発生器４で混合され、加水分解反応して
核となる種粒子を生成する。アルコキシド含有ガスは必
要により分岐管１２から抜き取られ、組成分析等に供さ
れる。種粒子を含むガスは第一段の凝縮器５で冷却され
て過飽和状態になり、種粒子を核として有核凝縮を行な
い、液滴エアロゾルになる。再加熱部７及び第二段の凝
縮器６を経て液滴径が整えられ、主反応器８に送られる
。そこで水蒸発器３から送られた過剰量の水蒸気と混合
され、加水分解反応して個々の液滴が固体粒子に変わる
。こうして生成した固体粒子は捕集器９のフィルターで
捕集される。１２は捕集器９を吸引する真空ポンプであ
る。主反応器８の出口側には分岐管が設けられ、希釈器
１３、静電分級器１４、凝縮核測定器１５が直列に接続
されている。Nitrogen gas containing alkoxide in a saturated state from the alkoxide evaporator 1 and nitrogen gas containing water vapor in a saturated state from the water evaporator 2 are mixed in a nuclear generator 4, and undergo a hydrolysis reaction to form seed particles that become nuclei. generate. The alkoxide-containing gas is extracted from the branch pipe 12 as necessary and subjected to compositional analysis or the like. The gas containing the seed particles is cooled to a supersaturated state in the first stage condenser 5, and undergoes nucleated condensation using the seed particles as a core to form droplet aerosol. After passing through the reheating section 7 and the second stage condenser 6, the droplet diameter is adjusted and sent to the main reactor 8. There, it is mixed with an excess amount of water vapor sent from the water evaporator 3, and undergoes a hydrolysis reaction, converting the individual droplets into solid particles. The solid particles thus generated are collected by the filter of the collector 9. 12 is a vacuum pump that sucks the collector 9. A branch pipe is provided on the outlet side of the main reactor 8, and a diluter 13, an electrostatic classifier 14, and a condensation nucleus measuring device 15 are connected in series.
分岐管から抜き出されたガスは希釈器１３において窒素
ガスボンベ１６から供給される窒素ガスで希釈され、静
電分級器で分級されて凝縮核測定器１５によって生成粒
子が粒径ごとに計数され、粒度分布や濃度が求められる
。The gas extracted from the branch pipe is diluted with nitrogen gas supplied from a nitrogen gas cylinder 16 in a diluter 13, classified by an electrostatic classifier, and generated particles are counted by particle size by a condensation nucleus measuring device 15. Particle size distribution and concentration are required.
上記装置を用いてアルミナ粒子の連続製造実験を行なっ
た。アルコキシドにはアルミニウムトリセカンダリ−ブ
トキシド（Ａ／！ （Ｃ，Ｈ５ＣＨ（ＣＨｊ） Ｏ）
３） （ＡＴＳＢ）を用いた。アルコキシド蒸発器１か
ら流出するＡＴＳＢ流量を１．ＯＸｌｏ−３ｍｏｌ／ｗ
ｉｎ、 Ｎｚ流量を１．０ｍｏｌ／ｌｌｌ１ｎとし、種
粒子生成用の水蒸発器２から流出するＨ ｚ Ｏ流量を
４．５ Ｘｌ０−’ｍｏｌ／ｍｉｎ。A continuous production experiment of alumina particles was conducted using the above apparatus. The alkoxide is aluminum trisec-butoxide (A/! (C, H5CH(CHj) O)
3) (ATSB) was used. The ATSB flow rate flowing out from the alkoxide evaporator 1 is set to 1. OXlo-3mol/w
In, the Nz flow rate is 1.0 mol/lll1n, and the H z O flow rate flowing out from the water evaporator 2 for seed particle generation is 4.5 Xl0-'mol/min.
Ｎ２流量を６．６ Ｘｌ０−’ｍｏｌ／ｍｆｎ、主反応
用水蒸発器３から流出するＨ２０流量を１．５ Ｘｌ０
−”ｍｏｌ／ｌｌ１ｉｎ、Ｎ２流量を０．２２＋ｍｏｌ
／ｓｉｎとした。核発生器の温度は１６０〜１８０°Ｃ
１圧力は７８０〜８６０Ｔｏｒｒに制御し、凝縮器の温
度は７９°Ｃにした。主反応器の温度は５０℃に、そし
て圧力は圧力は７８０〜８５０Ｔｏｒｒに制御した。尚
、凝縮器は一段とした。The N2 flow rate is 6.6 Xl0-'mol/mfn, and the H20 flow rate flowing out from the main reaction water evaporator 3 is 1.5 Xl0.
-”mol/ll1in, N2 flow rate 0.22+mol
/sin. The temperature of the nuclear generator is 160-180°C
1 The pressure was controlled at 780-860 Torr, and the condenser temperature was 79°C. The temperature of the main reactor was controlled at 50°C and the pressure was controlled at 780-850 Torr. In addition, the condenser was set to one stage.
定常状態における主反応器８から流出するガスを分析し
たところ、固体粒子の幾何平均粒径は０．１４２μ、幾
何標準偏差は１．２６９そして収率は７７．５％であっ
た。粒度分布を第２図に示す。この固体粒子は完全な球
形であった。Analysis of the gas flowing out from the main reactor 8 under steady state conditions revealed that the geometric mean particle size of the solid particles was 0.142μ, the geometric standard deviation was 1.269, and the yield was 77.5%. The particle size distribution is shown in Figure 2. The solid particles were perfectly spherical.
得られた固体粒子をマツフル炉で１２００°Ｃで１時間
仮焼し、結晶構造をＸ線回折により調べたところ完全に
αアルミナになっていた。このものも完全な球形であっ
た。The obtained solid particles were calcined in a Matsufuru furnace at 1200°C for 1 hour, and the crystal structure was examined by X-ray diffraction, and it was found to be completely α-alumina. This one was also perfectly spherical.
本実施例で用いた原料ＡＴＳＢ中の金属元素をＩＣＰ発
光分光法により測定した結果、／ｌの純度は９９．５％
であった。一方、仮焼したアルミナ粉を滴定・他により
組成分析した結果も、金属元素中のＡ２の比率は９９．
５％であり、仮焼粉は原料の純度を保持していた。As a result of measuring the metal elements in the raw material ATSB used in this example by ICP emission spectroscopy, the purity of /l was 99.5%.
Met. On the other hand, as a result of compositional analysis of calcined alumina powder by titration and other methods, the ratio of A2 in the metal elements was 99.
5%, and the calcined powder maintained the purity of the raw material.
実施例２
凝縮器の段数を２段としたほかは実施例１と同様にして
アルミナ粒子の連続製造実験を行なった。Example 2 A continuous production experiment of alumina particles was conducted in the same manner as in Example 1 except that the number of stages of the condenser was changed to two.
その結果、幾何平均粒径は０．１１３ｆｍ、幾何標準偏
差は１．３０９そして収率は５０．０％であった。粒度
分布を第３図に示す。As a result, the geometric mean particle size was 0.113 fm, the geometric standard deviation was 1.309, and the yield was 50.0%. The particle size distribution is shown in Figure 3.
本発明の方法により粒度分布が極めて狭い真球状の球形
超微粒子を容易に、しかも高純度で得ることができる。By the method of the present invention, spherical ultrafine particles having an extremely narrow particle size distribution can be easily obtained with high purity.
第１図は本発明の実施例で使用された装置の概略を示す
フローシートである。第２図及び第３図は実施例で得ら
れた粒子の粒度分布図であり、第４図及び第５図は凝縮
器温度と生成粒子の幾何平均径、幾何標準偏差、個数濃
度、体積濃度の関係を示すグラフである。FIG. 1 is a flow sheet showing an outline of an apparatus used in an example of the present invention. Figures 2 and 3 are particle size distribution charts of particles obtained in Examples, and Figures 4 and 5 are graphs of condenser temperature, geometric mean diameter, geometric standard deviation, number concentration, and volume concentration of particles produced. It is a graph showing the relationship.
Claims (1)
得る液滴ＣＶＤにおいて、液滴の核となる種粒子を導入
するに際し、主反応と同一系統の上流で原料アルコキシ
ドの一部を消費する反応操作により目的セラミック微粉
と同一物質又は乾燥もしくは焼成によって同一物質とな
りうる種粒子を作製することを特徴とする球形超微粒子
の連続製造方法In droplet CVD, which produces fine ceramic powder by reacting alkoxide and water vapor, when introducing seed particles that become the nucleus of droplets, a reaction operation that consumes a part of the raw material alkoxide upstream in the same system as the main reaction is used to produce the target ceramic. A method for continuous production of spherical ultrafine particles, characterized by producing seed particles that are the same substance as fine powder or can become the same substance by drying or firing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2284167A JPH04160007A (en) | 1990-10-24 | 1990-10-24 | Continuous production of spherical superfine particles |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2284167A JPH04160007A (en) | 1990-10-24 | 1990-10-24 | Continuous production of spherical superfine particles |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04160007A true JPH04160007A (en) | 1992-06-03 |
Family
ID=17675052
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2284167A Pending JPH04160007A (en) | 1990-10-24 | 1990-10-24 | Continuous production of spherical superfine particles |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04160007A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6740620B2 (en) | 2001-04-25 | 2004-05-25 | Rohn And Haas Company | Single crystalline phase catalyst |
-
1990
- 1990-10-24 JP JP2284167A patent/JPH04160007A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6740620B2 (en) | 2001-04-25 | 2004-05-25 | Rohn And Haas Company | Single crystalline phase catalyst |
| US6965050B2 (en) | 2001-04-25 | 2005-11-15 | Rohm And Haas Company | Single crystalline phase catalyst |
| US7208445B2 (en) | 2001-04-25 | 2007-04-24 | Rohm And Haas Company | Single crystalline phase catalyst |
| US7326668B2 (en) | 2001-04-25 | 2008-02-05 | Rohm And Haas Company | Single crystalline phase catalyst |
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