JPS6227005B2 - - Google Patents
Info
- Publication number
- JPS6227005B2 JPS6227005B2 JP58144474A JP14447483A JPS6227005B2 JP S6227005 B2 JPS6227005 B2 JP S6227005B2 JP 58144474 A JP58144474 A JP 58144474A JP 14447483 A JP14447483 A JP 14447483A JP S6227005 B2 JPS6227005 B2 JP S6227005B2
- Authority
- JP
- Japan
- Prior art keywords
- powder
- silica
- sic
- reaction
- gas
- 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.)
- Expired
Links
- 239000000843 powder Substances 0.000 claims description 25
- 229910010271 silicon carbide Inorganic materials 0.000 claims description 14
- 239000007789 gas Substances 0.000 claims description 12
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical group [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 claims description 11
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 claims description 8
- 238000000034 method Methods 0.000 claims description 6
- 229910000040 hydrogen fluoride Inorganic materials 0.000 claims description 4
- 229910052575 non-oxide ceramic Inorganic materials 0.000 claims description 4
- 239000011225 non-oxide ceramic Substances 0.000 claims description 4
- 229910052710 silicon Inorganic materials 0.000 claims description 2
- 239000010703 silicon Substances 0.000 claims description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 49
- 239000000377 silicon dioxide Substances 0.000 description 24
- 238000006243 chemical reaction Methods 0.000 description 13
- 238000011282 treatment Methods 0.000 description 6
- 239000007864 aqueous solution Substances 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 239000000919 ceramic Substances 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 238000001035 drying Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 239000010419 fine particle Substances 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 239000003960 organic solvent Substances 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- LIVNPJMFVYWSIS-UHFFFAOYSA-N silicon monoxide Chemical compound [Si-]#[O+] LIVNPJMFVYWSIS-UHFFFAOYSA-N 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- XWROUVVQGRRRMF-UHFFFAOYSA-N F.O[N+]([O-])=O Chemical compound F.O[N+]([O-])=O XWROUVVQGRRRMF-UHFFFAOYSA-N 0.000 description 1
- 229910004298 SiO 2 Inorganic materials 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000006229 carbon black Substances 0.000 description 1
- 238000010000 carbonizing Methods 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000005261 decarburization Methods 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- -1 silicon monoxide Chemical compound 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 238000001238 wet grinding Methods 0.000 description 1
Description
本発明はシリコン系セラミツクス原料粉末、特
に炭化ケイ素粉末の新規な精製方法に関する。
近年、省エネルギーおよび省資源(稀有金属の
代替)の観点から、高温機械材料としてのセラミ
ツクスが注目されている。中でも、炭化ケイ素は
有望な材料の一つとされ、既に実用化されている
例も多い。炭化ケイ素系セラミツクス原料粉末の
主な製法としては、
The present invention relates to a novel method for purifying silicon-based ceramic raw material powder, particularly silicon carbide powder. In recent years, ceramics have been attracting attention as high-temperature mechanical materials from the viewpoint of energy conservation and resource conservation (replacement of rare metals). Among these, silicon carbide is considered to be one of the most promising materials, and many examples have already been put into practical use. The main manufacturing methods for silicon carbide ceramic raw material powder are as follows:
【表】【table】
【表】
などが知られている。
上記各種の反応で製造された粉末に要求される
基本的性質としては高純度かつ微粒なことであ
る。しかしながら、純度の観点からみると生成粉
末中には原料、反応工程、炭素除去工程などから
の遊離シリカ(一酸化ケイ素も含む、以下同じ)
がかなり含有されている。また、微粒子化のため
には、解砕、粉砕等の後処理を必要とするが、こ
の段階でも上記粉末の酸化が進行してシリカ含有
率が増大する。
一般に、シリカはSiCなどの粉末の焼結を妨害
し、高温強度を低下させる代表的不純物の一つと
みなされている。そこで、従来、フツ酸水溶液あ
るいはフツ酸−硝酸水溶液処理によるシリカ除去
あるいは有機溶媒を利用した湿式粉砕による酸化
防止対策等がおこなわれているが、前者は、スラ
リー化のために大量の液体を取り扱わざるを得
ず、続く、濾過、乾燥、廃水処理等の操作も非常
に煩雑となり、大量生産には適さない。また、
HF水溶液を循環再利用する場合には、溶出金属
類が次第に濃縮されるので、高純度化には好まし
くない。しかも、水溶液処理は乾燥時粉末の強い
再凝集を招く点でも好ましくない。一方、後者の
場合でも多量の有機溶媒を使用するので、安全
上、環境上および経済上の観点から好ましい方法
とは言えない。
そこで、本発明者らは上記諸欠点を改良したシ
リカの除去方法について種々検討した結果、不純
物として遊離シリカを含むSiCなどの非酸化物系
セラミツクス粉末をフツ化水素ガスと50〜500℃
で反応させることによつてその目的を十分かつ容
易に達成できることを見い出した。
本発明を詳細に説明すると、非酸化物系セラミ
ツクス粉末の製造工程あるいは精製工程等で生成
したシリカを含む粉末をHFガス処理することに
よつてシリカ除去を行うもので、反応は下記のよ
うに進む。
SiO2+4HF→SiF4+2H2O
反応温度は50〜500℃の範囲が好ましく、50℃
以下では反応速度も遅くなり、また反応により生
成する水が凝縮し、スケーリングが起きるため、
操作面からも避ける方がよい。また高温になるほ
ど反応は速く進行するが、高温ほど、逆反応も起
り易くなり、総合的な効率を考慮すれば500℃以
下が好適である。反応形式はバツチ式あるいは連
続式のいずれでも良いが、固気反応であるため、
処理粉末を流動状態に保つ方が効率的である。本
発明の対象となる非酸化物系粉末はSiCを主成分
とするものである。
以上のように、SiC系の非酸化物系セラミツク
ス中に、製造時、粉砕時あるいは混合時生成した
シリカをフツ化水素ガスとの固気反応によつて除
去すれば、従来のフツ酸等を含む水溶液処理法と
比較し、煩雑な工程がさけられるので経済的に有
利であり、また粉末を乾式で取り扱うので再凝
集・凝結を完全に防止することができる点で、本
発明は非常に有意義である。
以下、実施例,比較例に基づいて本発明をさら
に詳細に説明する。
実施例 1
平均粒径2μのケイ砂をカーボンブラツク粉末
で高温還元炭化することによつて、2.1%のシリ
カを含むβ−SiCを得た。このものを脱炭、解砕
等の後処理を行うことによつて、シリカ含有量は
最終的に4.3%に達した。このシリカを含む粉末
100gをフツ化水素ガスを流しながらニツケル管
中で200℃30分間加熱することによつて粉末中の
シリカ含有率を0.04%まで低減することができ
た。また過剰のHFガスはSiF4およびH2Oガスか
ら分離、回収して再利用した。処理後の粉末の
SEM写真を第1図に示した。なお、シリカの定
量についてはJIS R−6124に従い以下の例もすべ
てこれに従つた。
実施例 2
実施例1においてβ−SiC製造時焼成炉の冷却
部に析出したSiCの繊維状粉末(ウイスカー)を
回収し、遊離シリカを分析したところ含有率は
3.6%であつた。このウイスカー50gを500の密
閉容器中で温度200℃で撹拌しながらHFガスを1
時間流した後、遊離シリカの分析をおこなつた結
果シリカ含有率は0.03%まで低下していた。
比較例 1
実施例1で製造した4・3%のシリカを含むβ
−SiCを47重量%濃度のHF水溶液(シリカに対
して、HFは大過剰に使用)中に30分間分散させ
てシリカ除去をおこなつたところシリカ含有率は
0.3%に減少し、除去効率は大略満足できるもの
であつたが、前述したように濾過、乾燥等がきわ
めて煩雑なものであつた。また、精製した粉末の
SEM写真を第2図に示したが粉末は著しい凝集
状態を呈していた。
比較例 2
実施例1と全く同様の操作を行なつたが、HF
ガス処理温度を20℃とした。この場合、SiC粉末
中のシリカ含有量は0.4%であつたが、反応の後
半でH2Oの凝縮現象がみられ、反応管出口付近に
シリカのスケールが析出して、HFガスの流れが
不安定となり好ましくなかつた。[Table] etc. are known. The basic properties required of the powders produced by the various reactions mentioned above are high purity and fine particles. However, from the viewpoint of purity, the generated powder contains free silica (including silicon monoxide, the same applies hereinafter) from raw materials, reaction processes, carbon removal processes, etc.
contains a considerable amount. In addition, post-treatments such as crushing and pulverization are required to form fine particles, but even at this stage, the oxidation of the powder proceeds and the silica content increases. Generally, silica is considered to be one of the typical impurities that interferes with the sintering of powders such as SiC and reduces high-temperature strength. Therefore, conventional measures to prevent oxidation have been taken, such as removing silica by treatment with a hydrofluoric acid aqueous solution or a hydrofluoric acid-nitric acid aqueous solution, or wet grinding using an organic solvent. Unavoidably, the subsequent operations such as filtration, drying, and wastewater treatment are also extremely complicated, making it unsuitable for mass production. Also,
When the HF aqueous solution is recycled and reused, the eluted metals are gradually concentrated, which is not preferable for achieving high purity. Moreover, the aqueous solution treatment is not preferable because it causes strong reaggregation of the powder during drying. On the other hand, even in the latter case, a large amount of organic solvent is used, so it cannot be said to be a preferable method from the viewpoints of safety, environment, and economy. Therefore, the present inventors investigated various methods for removing silica that improved the above-mentioned drawbacks, and found that non-oxide ceramic powder such as SiC containing free silica as an impurity was mixed with hydrogen fluoride gas at 50 to 500°C.
It has been found that the purpose can be sufficiently and easily achieved by reacting with . To explain the present invention in detail, silica is removed by treating powder containing silica produced in the manufacturing process or purification process of non-oxide ceramic powder with HF gas, and the reaction is as follows. move on. SiO 2 +4HF→SiF 4 +2H 2 O The reaction temperature is preferably in the range of 50 to 500℃, and 50℃
Below this, the reaction rate slows down, and the water produced by the reaction condenses, causing scaling.
It is better to avoid this from an operational standpoint. Further, the reaction progresses faster as the temperature increases, but the higher the temperature, the more likely reverse reactions occur, so in consideration of overall efficiency, a temperature of 500°C or lower is preferable. The reaction format may be either batch or continuous, but since it is a solid-gas reaction,
It is more efficient to keep the treated powder in a fluid state. The non-oxide powder that is the subject of the present invention has SiC as its main component. As described above, if the silica produced during manufacturing, crushing, or mixing in SiC-based non-oxide ceramics is removed through a solid-gas reaction with hydrogen fluoride gas, conventional hydrofluoric acid, etc. can be removed. The present invention is very significant in that it is economically advantageous as it avoids complicated steps compared to aqueous solution treatment methods that include It is. Hereinafter, the present invention will be explained in more detail based on Examples and Comparative Examples. Example 1 β-SiC containing 2.1% silica was obtained by reducing and carbonizing silica sand with an average particle size of 2 μm using carbon black powder at a high temperature. By subjecting this material to post-treatments such as decarburization and crushing, the silica content finally reached 4.3%. Powder containing this silica
By heating 100g of the powder at 200°C for 30 minutes in a nickel tube while flowing hydrogen fluoride gas, the silica content in the powder could be reduced to 0.04%. In addition, excess HF gas was separated from SiF 4 and H 2 O gas, recovered, and reused. of powder after processing
A SEM photograph is shown in Figure 1. The determination of silica was conducted in accordance with JIS R-6124 in all of the following examples. Example 2 In Example 1, the SiC fibrous powder (whiskers) precipitated in the cooling section of the firing furnace during β-SiC production was collected and analyzed for free silica, and the content was found to be
It was 3.6%. 50g of this whisker was stirred in a sealed container of 500℃ at a temperature of 200℃, and 1 portion of HF gas was added to it.
After a period of time, analysis of free silica revealed that the silica content had decreased to 0.03%. Comparative Example 1 β containing 4.3% silica produced in Example 1
-When removing silica by dispersing SiC in a 47% by weight aqueous HF solution (HF was used in large excess relative to silica) for 30 minutes, the silica content was
The removal efficiency decreased to 0.3%, which was generally satisfactory, but as mentioned above, filtration, drying, etc. were extremely complicated. In addition, purified powder
The SEM photograph shown in Figure 2 shows that the powder was in a markedly agglomerated state. Comparative Example 2 The same operation as in Example 1 was performed, but HF
The gas treatment temperature was 20°C. In this case, the silica content in the SiC powder was 0.4%, but a condensation phenomenon of H 2 O was observed in the latter half of the reaction, and silica scale was deposited near the outlet of the reaction tube, causing the flow of HF gas to It became unstable, which was not desirable.
第1図は本発明により精製したβ−SiC粉末の
SEM写真を、また、第2図は従来例により精製
したβ−SiC粉末のSEM写真を示すものである。
Figure 1 shows β-SiC powder purified by the present invention.
FIG. 2 shows a SEM photograph of β-SiC powder purified by a conventional example.
Claims (1)
分とする粉末を50〜500℃でフツ化水素ガスにて
処理することを特徴とする非酸化物系セラミツク
ス粉末の精製方法。1. A method for purifying non-oxide ceramic powder, which comprises treating a powder whose main component is silicon carbide containing an oxide of silicon with hydrogen fluoride gas at 50 to 500°C.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP58144474A JPS6036374A (en) | 1983-08-09 | 1983-08-09 | Purification of non-oxide ceramic powder |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP58144474A JPS6036374A (en) | 1983-08-09 | 1983-08-09 | Purification of non-oxide ceramic powder |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS6036374A JPS6036374A (en) | 1985-02-25 |
JPS6227005B2 true JPS6227005B2 (en) | 1987-06-11 |
Family
ID=15363134
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP58144474A Granted JPS6036374A (en) | 1983-08-09 | 1983-08-09 | Purification of non-oxide ceramic powder |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS6036374A (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS62141123A (en) * | 1985-12-16 | 1987-06-24 | Idemitsu Kosan Co Ltd | Production of fibrous carbonaceous material |
JP2668119B2 (en) * | 1988-03-15 | 1997-10-27 | 東海高熱工業株式会社 | Method for producing silicon carbide-silicon metal material |
JPH0622670B2 (en) * | 1989-03-30 | 1994-03-30 | 日本碍子株式会社 | Chemical decomposition method of silicon carbide |
JP5692514B2 (en) | 2010-12-24 | 2015-04-01 | 株式会社ジェイテクト | Electric power steering device and vehicle steering device |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS54133504A (en) * | 1978-04-10 | 1979-10-17 | Ibigawa Electric Ind Co Ltd | Manufacture of high density carborundum sintered body |
-
1983
- 1983-08-09 JP JP58144474A patent/JPS6036374A/en active Granted
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS54133504A (en) * | 1978-04-10 | 1979-10-17 | Ibigawa Electric Ind Co Ltd | Manufacture of high density carborundum sintered body |
Also Published As
Publication number | Publication date |
---|---|
JPS6036374A (en) | 1985-02-25 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
KR101766928B1 (en) | Method for producing silicon carbide | |
Kevorkijan et al. | Low-temperature synthesis of sinterable SiC powders by carbothermic reduction of colloidal SiO 2 | |
CN110055402B (en) | Treatment method and treatment device for tungsten waste | |
CN104328478A (en) | Preparation method of SiC crystal whisker | |
JP2010173916A (en) | Method of manufacturing silicon carbide from silicon waste | |
JP2014047105A (en) | Method for producing silicon carbide powder | |
CN102787011A (en) | Comprehensive treatment technology of waste mortar processing by crystalline silicon with no sewage and solid waste discharge | |
CN108441640B (en) | A kind of method that waste diamond abrasive material resource comprehensive utilization utilizes | |
US4342837A (en) | Sinterable silicon carbide powders and sintered body produced therefrom | |
CN113880136B (en) | Zirconium tetrachloride and/or silicon tetrachloride, preparation method and preparation device thereof | |
JPS6227005B2 (en) | ||
JPH0227316B2 (en) | ||
WO2009081725A1 (en) | Silicon reclamation method | |
CN103266234A (en) | Method for preparing silicon carbide particle-reinforced aluminum-based composite material from crystalline silica cutting waste material | |
JP5795728B2 (en) | Solid particulate collection method | |
CN111762787B (en) | Combined preparation method of chlorosilane and quartz | |
JP3796929B2 (en) | Almidros residual ash treatment method | |
CN114180541A (en) | Method for recovering and purifying waste silicon nitride | |
JPH0717706A (en) | Production of quartz glass powder | |
JPH0653564B2 (en) | Method for purifying hexagonal boron nitride | |
JPH10167725A (en) | Continuous production of alumina | |
JP2010030873A (en) | High purity silicon and production method thereof | |
JPH0790165B2 (en) | Purification method of powder | |
RU2026814C1 (en) | Method of high-pure silicon preparing | |
JPH11106212A (en) | Production unit for silicon carbide powder and production of silicon carbide powder using the same |