JPH02203932A - Method and apparatus for producing ultrafine particles - Google Patents
Method and apparatus for producing ultrafine particlesInfo
- Publication number
- JPH02203932A JPH02203932A JP1023599A JP2359989A JPH02203932A JP H02203932 A JPH02203932 A JP H02203932A JP 1023599 A JP1023599 A JP 1023599A JP 2359989 A JP2359989 A JP 2359989A JP H02203932 A JPH02203932 A JP H02203932A
- Authority
- JP
- Japan
- Prior art keywords
- raw material
- plasma
- ultrafine particles
- frequency induction
- supply pipe
- 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
- 239000011882 ultra-fine particle Substances 0.000 title claims abstract description 42
- 238000000034 method Methods 0.000 title description 8
- 239000002994 raw material Substances 0.000 claims abstract description 65
- 238000004519 manufacturing process Methods 0.000 claims abstract description 30
- 230000006698 induction Effects 0.000 claims abstract description 24
- 239000000843 powder Substances 0.000 claims description 43
- 238000010924 continuous production Methods 0.000 abstract description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 8
- 239000007789 gas Substances 0.000 description 7
- 239000000463 material Substances 0.000 description 7
- 239000002245 particle Substances 0.000 description 7
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 6
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 5
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 4
- 229910052786 argon Inorganic materials 0.000 description 4
- 239000012159 carrier gas Substances 0.000 description 4
- 229910052802 copper Inorganic materials 0.000 description 4
- 239000010949 copper Substances 0.000 description 4
- 239000010419 fine particle Substances 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 4
- 239000002184 metal Substances 0.000 description 4
- PMHQVHHXPFUNSP-UHFFFAOYSA-M copper(1+);methylsulfanylmethane;bromide Chemical compound Br[Cu].CSC PMHQVHHXPFUNSP-UHFFFAOYSA-M 0.000 description 3
- 238000004090 dissolution Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 229910052757 nitrogen Inorganic materials 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- PZNSFCLAULLKQX-UHFFFAOYSA-N Boron nitride Chemical compound N#B PZNSFCLAULLKQX-UHFFFAOYSA-N 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 229910021529 ammonia Inorganic materials 0.000 description 2
- 239000000919 ceramic Substances 0.000 description 2
- 238000011109 contamination Methods 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 125000004435 hydrogen atom Chemical class [H]* 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 239000010453 quartz Substances 0.000 description 2
- 229910021332 silicide Inorganic materials 0.000 description 2
- FVBUAEGBCNSCDD-UHFFFAOYSA-N silicide(4-) Chemical compound [Si-4] FVBUAEGBCNSCDD-UHFFFAOYSA-N 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- UONOETXJSWQNOL-UHFFFAOYSA-N tungsten carbide Chemical compound [W+]#[C-] UONOETXJSWQNOL-UHFFFAOYSA-N 0.000 description 2
- 229910052582 BN Inorganic materials 0.000 description 1
- 229910005331 FeSi2 Inorganic materials 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- CAVCGVPGBKGDTG-UHFFFAOYSA-N alumanylidynemethyl(alumanylidynemethylalumanylidenemethylidene)alumane Chemical compound [Al]#C[Al]=C=[Al]C#[Al] CAVCGVPGBKGDTG-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011362 coarse particle Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 239000000112 cooling gas Substances 0.000 description 1
- 239000012776 electronic material Substances 0.000 description 1
- -1 etc.) Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 210000003127 knee Anatomy 0.000 description 1
- 239000008204 material by function Substances 0.000 description 1
- 239000011812 mixed powder Substances 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 210000003720 plasmablast Anatomy 0.000 description 1
- 238000004663 powder metallurgy Methods 0.000 description 1
- 239000012495 reaction gas Substances 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
Landscapes
- Carbon And Carbon Compounds (AREA)
- Manufacture Of Metal Powder And Suspensions Thereof (AREA)
- Silicon Compounds (AREA)
- Physical Or Chemical Processes And Apparatus (AREA)
Abstract
Description
【発明の詳細な説明】
［産業上の利用分野］
本発明は、金属、セラミックス等の超微粒子の製造方法
及び製造装置に関し、粉体、粉末冶金、電子材料の機能
性原料粉等の製造に利用することができる。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method and apparatus for producing ultrafine particles of metals, ceramics, etc., and is suitable for producing powder, powder metallurgy, functional raw material powder for electronic materials, etc. can be used.
［従来の技術］
高周波誘導プラズマにより発生した１万にの高温熱プラ
ズマに粉末原料（及び反応性ガス）を導入して溶融、蒸
発（場合により反応を）させた後、象、冷して凝固させ
ることにより、超微粒子を製造する方法がある。得られ
た超微粒子は、磁気特性、熱電特性、熱伝導特性、粉体
特性等が良好であるため、超微粒子をそのまま、あるい
はこれを焼結し、各種の機能性材料として広範囲に使用
されている。そして、従来の製造方法に伴う問題点を解
決するための各種の改良方法が提案されている。[Prior art] Powder raw materials (and reactive gas) are introduced into high-temperature thermal plasma generated by high-frequency induction plasma, melted and evaporated (reacted in some cases), and then cooled and solidified. There is a method of manufacturing ultrafine particles by The obtained ultrafine particles have good magnetic properties, thermoelectric properties, thermal conductivity properties, powder properties, etc., so they are widely used as a variety of functional materials either as they are or by sintering them. There is. Various improvement methods have been proposed to solve the problems associated with conventional manufacturing methods.
例えば、特開昭６２−１７１９０２号公報に係る窒化ア
ルミニウム微粉末の合成法によれば、原料として金属ア
ルミニウム、アルゴン、窒素、水素、アンモニアめ他に
メタンを使用することにより、微粒子中の不純物酸素を
除去でき、また炭化アルミニラλ微粉末が均一に混合さ
□れた窒′化アルミニウム微粉末が得られる。For example, according to the method for synthesizing aluminum nitride fine powder according to JP-A-62-171902, impurity oxygen in the fine particles is removed by using metal aluminum, argon, nitrogen, hydrogen, ammonia, and methane as raw materials. can be removed, and fine aluminum nitride powder in which fine aluminum carbide powder is uniformly mixed can be obtained.
また、特開昭６３−８５００７号公報に係る窒化アルミ
ニウム超微粒子の製造方法によれば、磁気ポンプ効果を
抑止するためにプラズマフレーム中に金属アルミニウム
粉末が含まれるキャリアガスを周方向から連続′的に強
制導入すると共に、高純度超微粒子を得るためにキャリ
アガス導入後のプラズマフレーム中のやや温度が低い周
縁部へアンモニアガスを連続的に導入することを特徴と
している。Furthermore, according to the method for producing ultrafine aluminum nitride particles disclosed in Japanese Patent Application Laid-open No. 63-85007, a carrier gas containing metallic aluminum powder is continuously supplied from the circumferential direction in a plasma flame to suppress the magnetic pump effect. In addition, in order to obtain high-purity ultrafine particles, ammonia gas is continuously introduced into the periphery of the plasma flame, where the temperature is slightly lower after the introduction of the carrier gas.
４れらの従来の超微粒子の製造方法で使用する製造装置
においては、第２図に示すように、原料供給管２６は、
高周波誘導コイル帯域２４を構成するワークコイル２４
Ａ〜２４Ｚより上に位置するように設けられ、この吐出
口２５から下方のプラズマフレーム２９に粉末原料２７
を供給するようにしている。また、石英製のプラズマ発
生管２２は、□上部から下部の出口２３まで径が等しい
円筒状に形成されている。4. In the manufacturing apparatus used in these conventional methods for manufacturing ultrafine particles, as shown in FIG. 2, the raw material supply pipe 26 is
Work coil 24 constituting high frequency induction coil band 24
The powder raw material 27 is provided to be located above A to 24Z, and the powder raw material 27 is delivered from this discharge port 25 to the plasma flame 29 below.
We are trying to supply the following. Further, the plasma generation tube 22 made of quartz is formed into a cylindrical shape with the same diameter from the upper part to the outlet 23 at the lower part.
丸１Ｌ１
［発明が解決しようとする課題］
上述し、たような従来の製造装置を使用して超微粒子を
製造すると、導入された粉末原料２７又は生成した超微
粒子２８がプラズマ発生管２２に付着して加熱されたプ
ラズマ発傅管２２が冷却されるため、管２２が温度履歴
サイクルを受けて変質し、破壊され、その結果、装置の
連続運転が困難になる虞れがあった。また、このような
粉末原料２７又は微粒子２８のプラズマ発生管２２への
付着を考慮して原料供給量を抑えると、原料の大量処理
ができず、従って生産能率が低くなるという問題点が生
じていた。Circle 1L1 [Problems to be Solved by the Invention] When ultrafine particles are manufactured using the conventional manufacturing apparatus as described above, the introduced powder raw material 27 or the generated ultrafine particles 28 adhere to the plasma generation tube 22. Since the heated plasma blast tube 22 is cooled, the tube 22 undergoes a temperature history cycle, deteriorates in quality, and is likely to be destroyed, resulting in difficulty in continuous operation of the apparatus. Furthermore, if the amount of raw material supplied is suppressed in consideration of the adhesion of such powder raw materials 27 or fine particles 28 to the plasma generation tube 22, a problem arises in that a large amount of raw materials cannot be processed, and therefore production efficiency is reduced. Ta.
本発明は、生産能率を向上させることができ、また連続
生産を可能とする超微粒子の製造方法及び製造装置を提
供することを目的とする。An object of the present invention is to provide a method and apparatus for producing ultrafine particles that can improve production efficiency and enable continuous production.
［課題を解決するための手段］
本発明は、高周波誘導プラズ□マを用いた超微粒子の製
造方法において、粉末原料をプラズマフレーム中に直□
接供給することを特徴とする。[Means for Solving the Problems] The present invention provides a method for producing ultrafine particles using high-frequency induced plasma, in which a powder raw material is directly placed in a plasma flame.
It is characterized by supplying
前記粉末原料は、１種類の金属単体粉末＜’Ｍ ｇ、Ｚ
ｒ、Ｃｒ、Ｗ、ＡＩ、Ｆｅ等）、複数種の金属単体の混
合粉末、合金粉末（Ｔｉｃ、ＷＣ等）、セラミックス粉
末（Ａ ｌ ２０３、Ａ Ｉ Ｎ、、’Ｓ”””ｉ Ｎ
、Ｂ”’Ｎ 、 Ｓ’ ｉ Ｃ、Ｂ ４ Ｃ等）等任意
である。The powder raw material is one type of simple metal powder <'M g, Z
r, Cr, W, AI, Fe, etc.), mixed powders of multiple types of single metals, alloy powders (Tic, WC, etc.), ceramic powders (Al 203, A I N,,'S"""i N
, B'''N, S' i C, B 4 C, etc.).
この製造方法を実施するため゛の高周波誘導プラズマを
用いた超微粒子の製造装置“において、原料供”給管の
吐出口を高周波誘導コイル帯域内に設けたことを特徴と
する。In order to carry out this manufacturing method, the apparatus for producing ultrafine particles using high-frequency induction plasma is characterized in that the discharge port of the raw material supply pipe is provided within the zone of the high-frequency induction coil.
この原料供給管から、粉末原料と共に、あるいは別の供
給管から所要のプラズマ発生ガスを供給することができ
る。また、必要によりキャリアガス□あるいは反応ガス
としての牽゛素、アンモニア等も同時に供給してもよい
。A required plasma generating gas can be supplied from this raw material supply pipe together with the powder raw material or from another supply pipe. Further, if necessary, a carrier gas □ or a reaction gas such as hydrogen, ammonia, etc. may be supplied at the same time.
また、この超微粒子の製造装置において、前記高周波誘
導コイル帯域より下方のプラズマ発注管とチャンバーと
の連結部を、その径が出口に向かって大となるように形
成したことを特徴とする。Further, in this ultrafine particle manufacturing apparatus, the connecting portion between the plasma ordering tube and the chamber below the high-frequency induction coil band is formed such that its diameter increases toward the exit.
この連結部の具体的形状は、椀状、円錐状等任意である
。The specific shape of this connecting portion is arbitrary, such as a bowl shape or a conical shape.
［作用］
本発明によれば、原料供給管の吐出口を高周波誘導コイ
ル帯域内に設けて、粉末原料をプラズマフレーム中に直
接供給するようにしたので、プラズマ発生管内における
粉末原料の吐出位置及び生成された超微粒子の降下位置
が相対的に低くなる。[Function] According to the present invention, the discharge port of the raw material supply pipe is provided within the high frequency induction coil band so that the powder raw material is directly supplied into the plasma flame, so that the discharge position of the powder raw material within the plasma generation tube and The descending position of the generated ultrafine particles becomes relatively low.
この結果、粉末原料の吐出時及び超微粒予め降下時に、
粉末原料及び超微粒子が円周方向に拡散してもプラズマ
発生管に付着することがなくなる。As a result, when the powder raw material is discharged and the ultrafine particles are pre-dropped,
Even if the powder raw material and ultrafine particles are diffused in the circumferential direction, they will not adhere to the plasma generation tube.
また、このように構成することによって、プラズマフレ
ームのよめ安定化が図れる。Furthermore, with this configuration, the plasma flame can be improved and stabilized.
そして、本製造装置において、高周波誘導コイル帯域よ
り下方の連結部を、その径が出口に向かって大となるよ
うに形成すれば、上記構成に加えて、更に粉末原料及び
超微粒子のプラズマ発生管への付着現象を防止し、粉末
原料の大量、かつ連続処理が可能になる。In this manufacturing apparatus, if the connecting portion below the high-frequency induction coil band is formed so that its diameter increases toward the exit, in addition to the above configuration, the plasma generating tube for the powder raw material and ultrafine particles can be This prevents the phenomenon of adhesion to powder materials and enables continuous processing of large quantities of powdered raw materials.
［実施例］
第１図を参照して本発明の一実施例に係る超微粒子の製
造装置を説明する。[Example] Referring to FIG. 1, an apparatus for producing ultrafine particles according to an example of the present invention will be described.
この製造装置は、チャンバー１と、このチャンバー１の
上部中央に設けられた石英製のプラズマ発生管２とを有
し、チャンバー１の側面には図示しない超微粒子捕集装
置と排気装置を備えている。This manufacturing device has a chamber 1 and a quartz plasma generation tube 2 provided at the center of the upper part of the chamber 1, and is equipped with an ultrafine particle collection device and an exhaust device (not shown) on the side of the chamber 1. There is.
プラズマ発生管２の側面には、アルゴンガス等のプラズ
マガス供給口１１が設けられている。A plasma gas supply port 11 such as argon gas is provided on the side surface of the plasma generation tube 2 .
このプラズマ発生管２は、高周波誘導コイル帯域４を構
成するワークコイル４Ａ〜４Ｚが外周に沿って複数回巻
装される円筒部２Ａより成り、この下に出口３に向かっ
て径が次第に大きくなっているプラズマ発生管２とチャ
ンバー１との連結部１２を有する。なお、この連結部１
２の形状は、図示の椀状以外にも、円錐状等でもよい。This plasma generation tube 2 consists of a cylindrical part 2A around which work coils 4A to 4Z constituting a high-frequency induction coil band 4 are wound multiple times along the outer periphery. The plasma generating tube 2 has a connecting part 12 between the plasma generating tube 2 and the chamber 1. In addition, this connecting part 1
The shape of 2 may be a conical shape or the like other than the illustrated bowl shape.
出口３近傍には、外周に沿って、蒸発した粉末原料７の
冷却用ガス（アルゴンガス等）の導入孔１０を設けてお
く。In the vicinity of the outlet 3, an introduction hole 10 for cooling gas (argon gas, etc.) for the evaporated powder raw material 7 is provided along the outer periphery.
そして、プラズマ発生管２の中央には、吐出口５が高周
波誘導コイル帯域４内に位置するように原料供給管６を
設ける。この際、第１周円のワークコイル４Ａから最後
のワークコイル４ｚまでの距離をＨ１第１周目のワーク
コイル４Ａからプラズマ発生管２の吐出口５までの距離
をｈとしたとき、ｈ＞１／３Ｈとするのが、粉末原料７
及び生成・した超微粒子８のプラズマ発生管２内面への
付着を防止する上で好ましい。また、吐出口５は、高周
波誘導コイル帯域４を越えて下方迄挿入することもでき
るが、高周波誘導コイル帯域４内がよく、少なくともプ
ラズマフレーム９内である必要がある。しかし、あまり
深く挿入すると、粉末原料７とプラズマとの接触時間が
少なくなって微粒子化に影響があるため好ましくない。A raw material supply pipe 6 is provided at the center of the plasma generation tube 2 so that the discharge port 5 is located within the high frequency induction coil band 4. At this time, when the distance from the work coil 4A of the first circumference to the last work coil 4z is H1 and the distance from the work coil 4A of the first circumference to the discharge port 5 of the plasma generation tube 2 is h, h> Powder raw material 7 is 1/3H.
This is also preferable in terms of preventing the generated ultrafine particles 8 from adhering to the inner surface of the plasma generating tube 2. Further, the discharge port 5 can be inserted beyond the high-frequency induction coil zone 4 and even below, but it is preferable to insert it within the high-frequency induction coil zone 4, and it is necessary to insert it at least within the plasma flame 9. However, if it is inserted too deeply, the contact time between the powder raw material 7 and the plasma will be shortened, which will affect the formation of fine particles, which is not preferable.
なお、原料供給管６として使用する材質は、プラズマの
出力によって異なる。例えば、低出力の２０〜３０ｋＷ
程度では銅製の水冷管でもよいが、高出力に対応させる
ためには高融点材料である窒化ホウ素（ＢＮ）等の管を
用いるのがよい。また、原料供給管６の直径は、３０価
以下とするのがよい。Note that the material used for the raw material supply pipe 6 differs depending on the plasma output. For example, low output 20~30kW
To some extent, a water-cooled pipe made of copper may be used, but in order to cope with high output, it is better to use a pipe made of a material with a high melting point, such as boron nitride (BN). Further, the diameter of the raw material supply pipe 6 is preferably 30 or less.
上記構成に係る製造装置を使用して、次のように各実施
例に係る超微粒子を製造した。Using the manufacturing apparatus having the above configuration, ultrafine particles according to each example were manufactured as follows.
ｍ±
上記製造装置において、内径５７ｍｍのプラズマ発生管
２及び外径２０ｍｍ、導入径２ ｍｍの水冷式銅製原料
供給管６を使用し、吐出口５が第１周円のワークコイル
４Ａから１２ｍｍ下方に位置するように原料供給管６を
プラズマ発生管２内に設けた。m± In the above manufacturing apparatus, a plasma generation tube 2 with an inner diameter of 57 mm and a water-cooled copper raw material supply tube 6 with an outer diameter of 20 mm and an introduction diameter of 2 mm are used, and the discharge port 5 is located 12 mm below the work coil 4A of the first circumference. The raw material supply pipe 6 was provided inside the plasma generation tube 2 so as to be located at .
このプラズマ発生管２内にプラズマフレーム９を発生さ
せ、このプラズマフレーム９中に直接粉末原料７である
鉄シリサイドＦｅＳｉ２粉末を供給して、溶融、蒸発さ
せ、そしてＡｒガスで象、冷凝固させることによりＦｅ
Ｓｉ２超微粒子８を製造した。製造時の具体的な諸条件
は下記の通りである。A plasma flame 9 is generated in the plasma generation tube 2, and iron silicide FeSi2 powder, which is the powder raw material 7, is directly supplied into the plasma flame 9, melted and evaporated, and then irradiated with Ar gas and cooled and solidified. By Fe
Si2 ultrafine particles 8 were produced. The specific conditions during manufacturing are as follows.
ＲＦパワー ・・・・・・・・・・・・２６ｋＷ粉
末原料供給量 ・・・・・・・・・・・・１５０ ｇ
／ｍｉｎプラズマＡｒ流量・・・・・・・・・・・・７
５１／ｍ１ｎＨ２流量 ・・・・・・・・・・・
・２Ｉ！／ｍｊｎ処理時間 ・・・・・・・・・
・・・２０時間なお、プラズマＡｒ流量とは、粉末原料
７のキャリア用ガスと側面から供給するＡｒガスの総量
である。また、Ｈ２は、ＲＦプラズマ炉１内に供給し、
アルゴンプラズマの温度制御とプラズマを安定化させる
作用を有する。RF power: 26 kW Powder raw material supply: 150 g
/min Plasma Ar flow rate...7
51/m1nH2 flow rate...
・2I! /mjn processing time ・・・・・・・・・
...20 hours The plasma Ar flow rate is the total amount of the carrier gas for the powder raw material 7 and the Ar gas supplied from the side. Further, H2 is supplied into the RF plasma furnace 1,
It has the effect of controlling the temperature of argon plasma and stabilizing the plasma.
得られたＦｅ５ｉｚ超微粒子８は、１５００人前後の粒
径を有していた。The obtained Fe5iz ultrafine particles 8 had a particle size of about 1,500 particles.
この製造装置により、１５０ ｇ ／ｍｉｎ という大
量の粉末原料７を処理することができた。そして、製造
時において従来のような原料粉末７及び化成した超微粒
子８のプラズマ発生管２内面への付着は発生しなかった
。また、吐出口５が高周波誘導コイル帯域４内に位置す
るように銅製原料供給管６をプラズマ発生管２内に設け
たにも拘らず、比較的低出力であり、且つ、原料供給管
６を水冷式としたため、原料供給管６の溶解は発生せず
、従って管材の溶解による超微粒子８への汚染も生じな
かった。加えて、原料供給管６が高周波誘導コイル帯域
４内に位置しているが、安定なプラズマフレーム９が得
られた。This manufacturing apparatus was able to process a large amount of powder raw material 7 at a rate of 150 g/min. During manufacturing, the raw material powder 7 and the chemically formed ultrafine particles 8 did not adhere to the inner surface of the plasma generating tube 2 as in the conventional case. Furthermore, although the copper raw material supply pipe 6 is provided in the plasma generation tube 2 so that the discharge port 5 is located within the high frequency induction coil zone 4, the output is relatively low, and the raw material supply pipe 6 is Since the system was water-cooled, the raw material supply pipe 6 did not dissolve, and therefore the ultrafine particles 8 were not contaminated by dissolution of the pipe material. In addition, although the raw material supply pipe 6 was located within the high frequency induction coil zone 4, a stable plasma flame 9 was obtained.
一実１Ｌ性」−
上記製造装置において、内径８０ｍｍのプラズマ発生管
２及び外径９胴、導入径１．５＋ｎｎ＋の窒化ホウ素（
ＢＮｉ製の原料供給管６を使用し、吐出口５が第１同口
のワークコイル４Ａから２１ ＋ｎｍ下方に位置するよ
うに原料供給管６をプラズマ発生管２内に設けた。- In the above manufacturing equipment, a plasma generating tube 2 with an inner diameter of 80 mm, an outer diameter of 9 cylinders, and boron nitride (with an introduction diameter of 1.5+nn+)
A raw material supply pipe 6 made of BNi was used, and the raw material supply pipe 6 was provided in the plasma generation tube 2 so that the discharge port 5 was located 21 + nm below the first work coil 4A.
このプラズマ発生管２内にプラズマフレーム９を発生さ
せ、このプラズマフレーム９中どこ直接粉末原料７ｔあ
るタンゲス夢ンカーバイド（ＷＣ）粉末を供給して、Ｗ
Ｃ超微粒子８を製造した。製造時の具体的な諸条件は下
記の通りである。A plasma flame 9 is generated in this plasma generation tube 2, and 7 tons of tungsten carbide (WC) powder is directly supplied into the plasma flame 9.
C ultrafine particles 8 were produced. The specific conditions during manufacturing are as follows.
ＲＦパワー ・・・・・・・・・・・・７９ｋＷ粉
末原料供給量 ・・・・・・・・・・・・２１０ ｇ
／ ｍｉｎ”□：□プラズマＡｒ流量・・・・・・・・
・・・・１０５４２７ｍ１ｎＨ２流量 ・・・・
・・・・・・・・１１ ｌ／ｍｉｎ処理時間 ・
・・・・・・・・・・・２２時間得られｔｉ Ｗｃ超微
粒子８は、１０００人前後の粒径を有していた。RF power: 79 kW Powder raw material supply: 210 g
/ min"□:□Plasma Ar flow rate...
...105427m1nH2 flow rate ...
・・・・・・・・・11 l/min processing time ・
......The ti Wc ultrafine particles 8 obtained after 22 hours had a particle size of about 1000 particles.
上記実施例１と同様、この製造装置によっても、２１０
ｇ ／ｍｉｎ という大量の粉末原料７を処理するこ
とができた。そして、製造時において粉末原料７及び生
成した超微粒子８のプラズマ発生管２内面への付着は発
生しなかった。また、吐出口５が高周波誘導コイル帯域
４内に位置するように原料供給管６をプラズマ発生管２
内に設け、ＲＦパワーが高出力であったにも拘らず、Ｂ
Ｎ製原料供給管６を使用したため、原料供給管６の溶解
は発生せず、従って管材の溶解による超微粒子８への汚
染も生じなかった。加えで、原料供給管６が高周波誘導
コイル帯域４内に位置しているが、安定なプラズマフレ
ーム９が得られた。As in Example 1 above, this manufacturing apparatus also produces 210
It was possible to process a large amount of powder raw material 7 at a rate of 1 g/min. During manufacturing, the powder raw material 7 and the generated ultrafine particles 8 did not adhere to the inner surface of the plasma generation tube 2. In addition, the raw material supply pipe 6 is connected to the plasma generation tube 2 so that the discharge port 5 is located within the high frequency induction coil zone 4.
Although the RF power was high, B
Since the raw material supply pipe 6 made of N was used, no dissolution of the raw material supply pipe 6 occurred, and therefore no contamination of the ultrafine particles 8 due to dissolution of the pipe material occurred. In addition, although the raw material supply pipe 6 was located within the high frequency induction coil zone 4, a stable plasma flame 9 was obtained.
北笠貰
第２図に示ず従来の製造装置において、内径５１ｍｍｄ
）プラズマ発生管２２及び外径２０胴、導入径２ ｍｍ
の銅製原料供給＊２６を使用し、吐出口２５が第１同口
のワークコイル２４Ａから１５ｍｍ上方に位置するよう
に原料供給管２６をブラズオ発生簀２２内に設けた。In the conventional manufacturing equipment (not shown in Figure 2), the inner diameter was 51mmd.
) Plasma generation tube 22 and outer diameter 20 shell, introduction diameter 2 mm
A raw material supply pipe 26 made of copper was used, and the raw material supply pipe 26 was provided in the Brazuo generation cage 22 so that the discharge port 25 was located 15 mm above the work coil 24A of the first same port.
このプラズマ発生管２２内にプラズマブレームン９を発
生させ、このプラズマフレーム２９の上分から福末原料
２７である秩シリサイドＦｅ５ｉ”ｚ物末番供給して、
Ｆｅ’５ｉｚｌ微粒子２８を製造した。製造時の具体的
な諸条件は下記の通りである。Plasma flame 9 is generated in this plasma generation tube 22, and Chichi silicide Fe5i"z, which is the Fukusue raw material 27, is supplied from the upper part of this plasma flame 29.
Fe'5izl fine particles 28 were produced. The specific conditions during manufacturing are as follows.
ＲＦパワー ・・・・・・・・・・・・２ ’６
ｋ Ｗ粉末原料供給量 ・・・・・・・・・・・・１５
−Ｏｇ ／ｍｉｎプラズマＡｒ流量・・・・・・・・・
・・・７５ｆｆｉ／ｍ１ｎＨ８流量 ・・・・・
・・・・・・・２１／ｍｉｎ処理時間 ・・・・
・・・・・・・・セ０時間 ・ ニー１□□′□得ら
れたＦｅ’Ｓｉｚ超微粒子′２８は、１４００人前後の
粒径を有していた。RF power ・・・・・・・・・・・・2 '6
kW Powder raw material supply amount ・・・・・・・・・・・・15
-Og/min plasma Ar flow rate...
・・・75ffi/m1nH8 flow rate ・・・・・・
・・・・・・21/min processing time ・・・・・・
...Se 0 hours - Knee 1□□'□The obtained Fe'Siz ultrafine particles '28 had a particle size of about 1400 particles.
□ 上記実施例１と同様に１５０ ｇ ／ｍｉｎの大量
の粉末原料２７を処理したところ、供給し□た粉末原料
２７と生成した超微粒子２日がプラズマ発生管２２内面
に付着し、プラズマ発生管２２が温ｉ！艙歴サイクルを
受ける結果□、・プラズマ発生管２２に破損の広れが生
じた。そして、原料の処理量をｌＯ′・Ｏｇ／１ｌｌｉ
ｎ に落とした場合には、プラズマ発生管２２への粉末
原料２７の付着は生じなかった。□ When a large amount of powder raw material 27 was processed at a rate of 150 g/min in the same manner as in Example 1, the supplied powder raw material 27 and the generated ultrafine particles adhered to the inner surface of the plasma generation tube 22, causing the plasma generation tube to deteriorate. 22 is hot! As a result of being subjected to the vessel history cycle, damage spread to the plasma generation tube 22. Then, the processing amount of raw material is 1O'・Og/1lli
n, the powder raw material 27 did not adhere to the plasma generating tube 22.
従って、従来の峻造装置によれば、上記実施例のような
大量処理は無却であった。なお、本比較例の場合、原料
供給管２６は高周波誘導コイル帯域２４より上方に設置
すられているので、当然原料供給管２６の熔解も管材の
超微粒子２８への汚染も生じなかった。しかし、プラズ
マブレーム２９は不安定で、得られた超微粒子２８中に
は、かなりの未処理の原料である粗粒の存在が認められ
た。Therefore, with the conventional steepening device, it was impossible to process a large amount as in the above embodiment. In the case of this comparative example, since the raw material supply pipe 26 was installed above the high-frequency induction coil zone 24, naturally neither melting of the raw material supply pipe 26 nor contamination of the ultrafine particles 28 of the tube material occurred. However, the plasma blaze 29 was unstable, and the presence of a considerable amount of coarse particles, which were unprocessed raw materials, was observed in the obtained ultrafine particles 28.
［発明の効果］
本発明によれば、高品質超微粒子の大量生産及び装置の
連続運転が可能になる。[Effects of the Invention] According to the present invention, mass production of high-quality ultrafine particles and continuous operation of the apparatus are possible.
第１図は実施例に係る超微粒子の製造装置の要部断面図
、第２図は従来例に係る超微粒子の製造装置の要部断面
図である。
２．２２・・・プラズマ発生管、３．２３・・・出口、
４．２４・・・高周波誘導コイル帯域、５，２５・・・
吐出口、６．２６・・・原料供給管、７
料、８，２８・・・超微粒子、９
レーム、１２・・・連結部。
２７・・・粉末原
２９・・・プラスマフFIG. 1 is a sectional view of a main part of an apparatus for producing ultrafine particles according to an embodiment, and FIG. 2 is a sectional view of a main part of an apparatus for producing ultrafine particles according to a conventional example. 2.22...Plasma generation tube, 3.23...Exit,
4.24...High frequency induction coil band, 5,25...
Discharge port, 6.26... Raw material supply pipe, 7 Material, 8, 28... Ultrafine particles, 9 Rem, 12... Connection portion. 27... Powder original 29... Plus muff
Claims (3)
において、粉末原料をプラズマフレーム中に直接供給す
ることを特徴とする超微粒子の製造方法。(1) A method for producing ultrafine particles using high-frequency induced plasma, characterized in that a powder raw material is directly supplied into a plasma flame.
において、原料供給管の吐出口を高周波誘導コイル帯域
内に設けたことを特徴とする超微粒子の製造装置。(2) An apparatus for producing ultrafine particles using high-frequency induction plasma, characterized in that the discharge port of the raw material supply pipe is provided within the band of a high-frequency induction coil.
前記高周波誘導コイル帯域より下方のプラズマ発生管と
チャンバーとの連結部を、その径が出口に向かって大と
なるように形成したことを特徴とする超微粒子の製造装
置。(3) In the ultrafine particle manufacturing apparatus according to the second claim,
An apparatus for producing ultrafine particles, characterized in that a connecting portion between the plasma generating tube and the chamber below the high-frequency induction coil band is formed such that its diameter increases toward the exit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1023599A JPH02203932A (en) | 1989-01-31 | 1989-01-31 | Method and apparatus for producing ultrafine particles |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1023599A JPH02203932A (en) | 1989-01-31 | 1989-01-31 | Method and apparatus for producing ultrafine particles |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH02203932A true JPH02203932A (en) | 1990-08-13 |
Family
ID=12115066
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1023599A Pending JPH02203932A (en) | 1989-01-31 | 1989-01-31 | Method and apparatus for producing ultrafine particles |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02203932A (en) |
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|---|---|---|---|---|
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| KR100446923B1 (en) * | 2001-06-22 | 2004-09-01 | 인하대학교 산학협력단 | A method for converting a rough shaped silica powder into spherical silica powder |
| JP2007503973A (en) * | 2003-08-28 | 2007-03-01 | テクナ・プラズマ・システムズ・インコーポレーテッド | Methods for the synthesis, separation and purification of powder materials |
| JP2008285700A (en) * | 2007-05-15 | 2008-11-27 | Sumitomo Metal Mining Co Ltd | Molybdenum ultrafine powder, and method for producing the same |
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| JP2015086413A (en) * | 2013-10-29 | 2015-05-07 | 大陽日酸株式会社 | Method of producing composite superfine particle |
| US9687811B2 (en) | 2014-03-21 | 2017-06-27 | SDCmaterials, Inc. | Compositions for passive NOx adsorption (PNA) systems and methods of making and using same |
| US10086356B2 (en) | 2014-03-21 | 2018-10-02 | Umicore Ag & Co. Kg | Compositions for passive NOx adsorption (PNA) systems and methods of making and using same |
| US10413880B2 (en) | 2014-03-21 | 2019-09-17 | Umicore Ag & Co. Kg | Compositions for passive NOx adsorption (PNA) systems and methods of making and using same |
| JP2015178449A (en) * | 2015-03-09 | 2015-10-08 | 株式会社Ｌｓ Ｎｏｖａ | removal of contaminated radioactive material |
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