JPS6252129A - Production of fine metal oxide particle - Google Patents
Production of fine metal oxide particleInfo
- Publication number
- JPS6252129A JPS6252129A JP18741585A JP18741585A JPS6252129A JP S6252129 A JPS6252129 A JP S6252129A JP 18741585 A JP18741585 A JP 18741585A JP 18741585 A JP18741585 A JP 18741585A JP S6252129 A JPS6252129 A JP S6252129A
- Authority
- JP
- Japan
- Prior art keywords
- metal hydroxide
- metal
- metal oxide
- aqueous solution
- reaction
- 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
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B13/00—Oxygen; Ozone; Oxides or hydroxides in general
- C01B13/14—Methods for preparing oxides or hydroxides in general
- C01B13/36—Methods for preparing oxides or hydroxides in general by precipitation reactions in aqueous solutions
Abstract
Description
【発明の詳細な説明】
［産業上の利用分野コ
本発明は、極めて微小な例えば四三酸化鉄、四三酸化コ
バルト、酸化マンガンなどの金属酸化物粒子を簡単に効
率よく製造する方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for easily and efficiently producing extremely fine metal oxide particles such as triiron tetroxide, tricobalt tetroxide, manganese oxide, and the like.
［従来技術およびその問題点］
一般に微小な金属酸化物粒子は顔料用、研磨材用、電磁
気材料用などとして有用である。例えば三二酸化鉄は、
０．１μｍ以下の微小粒子にすることによって、紫外線
を通過させ難い特殊顔料としての用途も生じ、その有用
性が増大する。また、フェライトは一般に酸化鉄と他の
金属酸化物も・しくは炭酸塩とを混合し、１０００℃以
上の高温て固体反応により合成されるが、そのような固
体反応を容易に達成するために、原料として微小な酸化
鉄が望まれていイ。[Prior art and its problems] In general, fine metal oxide particles are useful as pigments, abrasives, electromagnetic materials, and the like. For example, iron sesquioxide
By making the particles smaller than 0.1 μm, they can also be used as special pigments that do not easily transmit ultraviolet rays, increasing their usefulness. Additionally, ferrite is generally synthesized by mixing iron oxide with other metal oxides or carbonates and performing a solid-state reaction at high temperatures of 1000°C or higher, but in order to easily achieve such a solid-state reaction, , minute iron oxide is desired as a raw material.
従来、微小な金属酸化物粒子の製造方法としては、一般
に（１）金属陽イオンを難溶の水酸化物、炭酸塩、蓚酸
塩などの形で沈殿させ、これを仮焼する方法、（２）金
属アルコキシドを加水分解して得られる沈殿物を仮焼す
る方法、（３）鉄酸化物として、例えば特開昭５８−２
０７３３号で提案されているように、レビドクロサイト
γ−Ｆｅ００ Ｈをオートクレーブ中で撹拌しながら、
２００℃で３０分間程度の水熱処理をして微小なα型三
二酸化鉄を得る方法などがある。Conventionally, methods for producing fine metal oxide particles generally include (1) a method of precipitating metal cations in the form of hardly soluble hydroxide, carbonate, oxalate, etc., and calcining this; ) A method of calcining a precipitate obtained by hydrolyzing a metal alkoxide, (3) As an iron oxide, for example, JP-A-58-2
As proposed in No. 0733, levidocrocite γ-Fe00 H was stirred in an autoclave while
There is a method of obtaining minute α-type iron sesquioxide by hydrothermal treatment at 200° C. for about 30 minutes.
しかしながら、上記した如き従来法においては、沈殿の
生成時に粒子が微小であっても、粒径が不揃いであった
り、その後の焼成工程で粒子の二次成長が起こり易く粗
大化したりして、所望の微小な金属酸化物粒子が簡単に
得られなかったり、また高温、加圧下の反応を必要する
など工業的操作において工程がＶ！雑であるなどの欠点
を有する。However, in the conventional method as described above, even if the particles are minute when forming the precipitate, the particle size may be uneven, or the particles may easily undergo secondary growth in the subsequent firing process and become coarse. In industrial operations, the process is difficult, such as not being able to easily obtain minute metal oxide particles, or requiring reactions at high temperatures and pressure. It has disadvantages such as being sloppy.
［問題を解決するための手段］
本発明者らは、上記したような従来法における問題を解
決し、微小な金属酸化物を簡便に製造する方法について
鋭怠研究を重ねた。その結果、金属水酸化物を水溶液中
で酸化反応させることにより、粒度の揃った微小な金属
酸化物粒子が簡単に得られることを見出して、本発明を
提供するとと至ったものである。即ち、本発明は金属水
酸化物を水溶液中で酸化反応し、必要により生成物を焼
成することを特徴とする微小な金属酸化物粒子の製造方
法である。[Means for Solving the Problems] The present inventors have conducted intensive research on a method for easily producing minute metal oxides by solving the problems in the conventional methods as described above. As a result, the inventors discovered that fine metal oxide particles with uniform particle size can be easily obtained by subjecting a metal hydroxide to an oxidation reaction in an aqueous solution, leading to the present invention. That is, the present invention is a method for producing minute metal oxide particles, which is characterized by subjecting a metal hydroxide to an oxidation reaction in an aqueous solution and, if necessary, calcining the product.
本発明に用いる金属水酸化物の金属としては、例えば鉄
、コバルト、ニッケル、亜鉛、スズ、マンガンなどであ
る。かかる金属の水酸化物は、一般に対応する金属塩の
水溶液に苛性アルカリを添加反応させてマ：Ｉられる。Examples of the metal of the metal hydroxide used in the present invention include iron, cobalt, nickel, zinc, tin, and manganese. Such metal hydroxides are generally prepared by adding caustic alkali to an aqueous solution of the corresponding metal salt.
したがって、対応の金属塩としては水溶性の金属化合物
が用いられ、例えば塩化鉄、塩化コバルト、塩化第１ス
ズ、塩化マンガンなどの塩化物、硫酸第１鉄、５Ｒ酸亜
鉛、硫酸錫、硫酸マンガンなどの硫酸塩、あるいは硝酸
塩などが好適である。Therefore, water-soluble metal compounds are used as the corresponding metal salts, such as chlorides such as iron chloride, cobalt chloride, stannous chloride, and manganese chloride, ferrous sulfate, zinc 5R acid, tin sulfate, and manganese sulfate. Sulfates such as, nitrates, etc. are suitable.
次に、本発明における金属水酸化物の酸化反応は、水溶
液中で一般に酸化剤の添加によって良好に達成される。Next, the oxidation reaction of the metal hydroxide in the present invention is generally well achieved in an aqueous solution by adding an oxidizing agent.
したがフて、本発明は上記した金属水酸化物の合成と該
金属水酸化物の酸化反応とを、同一の反応容器において
水酸化中で連続的に実施することが出来る。なお、酸化
剤としては、金属水酸化物の酸化反応を充分に達成でき
るものであれば特に制限されないが、特に次亜塩素酸ナ
トリウム、次曲塩素酸カリウム、次亜塩素酸カルシウム
などの次亜塩素酸塩が好適であるが、そのほか次亜臭酸
ナトリウム、次亜臭酸カリウムなどの酸素酸塩も好まし
く用いられる。Therefore, in the present invention, the synthesis of the metal hydroxide and the oxidation reaction of the metal hydroxide described above can be carried out continuously in the same reaction vessel during hydration. The oxidizing agent is not particularly limited as long as it can sufficiently achieve the oxidation reaction of metal hydroxide, but in particular hypochlorite such as sodium hypochlorite, potassium hypochlorite, calcium hypochlorite, etc. Chlorates are preferred, but oxyacids such as sodium hypobromite and potassium hypobromite are also preferably used.
本発明において、特に粒度分布が揃った金属酸化物粒子
を得るためには、金属水酸化物の濃度を一般に１５重量
％以下、特に５〜１０重竜％に調整した水溶液中で酸化
反応を実施することが好ましい。即ち、本発明における
金属水酸化物の酸化反応は極めて速やかに達成されるた
めに、該金属水酸化物の濃度が上記した１５重量％より
高い場合には、酸化反応が局所的となり、得られる金属
酸化物の粒度分布か不揃いになる結果を招く。また、金
属水酸化物の濃度が上記の５重量％より低い場合には、
反応が達成されても効率的でない。In the present invention, in order to obtain metal oxide particles with a particularly uniform particle size distribution, the oxidation reaction is carried out in an aqueous solution in which the concentration of metal hydroxide is generally adjusted to 15% by weight or less, particularly 5 to 10% by weight. It is preferable to do so. That is, since the oxidation reaction of the metal hydroxide in the present invention is achieved extremely quickly, if the concentration of the metal hydroxide is higher than the above-mentioned 15% by weight, the oxidation reaction becomes localized and the resulting This results in uneven particle size distribution of the metal oxide. In addition, if the concentration of metal hydroxide is lower than the above 5% by weight,
Even if the reaction is achieved, it is not efficient.
さらに、反応温度が低すぎる場合には、金属水酸化物の
酸化反応が速やかに達成されなくなり効率的でないばか
りでなく、微小で巨っ粒度分布の揃った金属酸化物粒子
が得られ難い。したがって、反応温度は一般に２０〜１
００℃、特に９０℃程度が好ましい。Furthermore, if the reaction temperature is too low, the oxidation reaction of the metal hydroxide will not be accomplished quickly, which will not only be inefficient, but also make it difficult to obtain metal oxide particles with a uniform particle size distribution. Therefore, the reaction temperature is generally between 20 and 1
The temperature is preferably about 00°C, especially about 90°C.
本発明における金属水酸化物の酸化反応は、例えば下記
式
％式％
のように、速やかに達成される。しかしながら、例えば
コバルト、ニッケル、スズなど金属の種類によっては、
その金属水酸化物は酸化反応が充分に達成されない場合
がある。即ち、例えばコバルト水酸化物の酸化反応は、
・一般に下記式２式％
のような形にとどまるものと推測される。このような金
属水酸化物の酸化反応による生成物は、通常の分析によ
って容易に確認することが出来る。The oxidation reaction of the metal hydroxide in the present invention is quickly accomplished, for example, as shown in the following formula %. However, depending on the type of metal, such as cobalt, nickel, and tin,
The metal hydroxide may not undergo a sufficient oxidation reaction. That is, for example, the oxidation reaction of cobalt hydroxide is
・It is generally assumed that the formula will remain in the form shown below. Products resulting from such oxidation reactions of metal hydroxides can be easily confirmed by conventional analysis.
本発明において、上記したような金属水酸化物の酸化反
応が充分に達成されていない場合には、次いで反応生成
物を反応液より分離、乾燥後、ゆるやかな条件下で焼成
することによって、所望の微小な、金属酸化物を得るこ
とが出来る。焼成条件は、一般に温度２００〜３００℃
、時間５〜ｌＯ分間で充分である。本発明においては、
予め金属水酸化物の酸化反応により可成り酸化された生
成物が焼成ここ供せられるため、比較的穏和な焼成によ
り粒子の粗大化を伴うことなく、目的とする微小な金属
酸化物粒子を得ることが出来る。In the present invention, if the oxidation reaction of the metal hydroxide as described above is not fully achieved, the reaction product is then separated from the reaction solution, dried, and then calcined under mild conditions to achieve the desired result. It is possible to obtain minute metal oxides. Firing conditions are generally a temperature of 200 to 300°C.
, a time of 5 to 10 minutes is sufficient. In the present invention,
Since the product that has been significantly oxidized in advance by the oxidation reaction of the metal hydroxide is subjected to the calcination, the desired fine metal oxide particles can be obtained through relatively mild calcination without coarsening of the particles. I can do it.
［効果］
以上に説明したように、本発明は従来法に比べて焼成工
程を必要とする場合でも、粒子の粗大化がなく、例えば
０．０５μｍ以下の極めて微小、かつ粒度の揃った金属
酸化物粒子を得ることが出来る。また、本発明は加圧下
の反応、格別の焼成条件および操作を必要とせず、迅速
に効率よく且つ安価に微小な金属酸物を製造することが
出来るため、工業的に極めて有用な方法である。[Effects] As explained above, the present invention does not cause coarsening of particles even when a firing step is required compared to conventional methods, and produces extremely fine metal oxide particles of, for example, 0.05 μm or less and uniform particle size. It is possible to obtain particles of matter. Furthermore, the present invention does not require reaction under pressure, special firing conditions, or operations, and can produce minute metal oxides quickly, efficiently, and inexpensively, so it is an extremely useful method industrially. .
［実施例コ
以下、本発明の実施例を示すが、本発明はこれらの実施
例に制限されるものでない。[Examples] Examples of the present invention will be shown below, but the present invention is not limited to these examples.
実施例１
硫酸第１鉄（７７ｋｍ）３０ｇを水６ｏｏｒｒｌに溶解
した溶液に、別に用意した苛性ソーダ８．４ｇを水ｌｏ
ｏｍ見に溶解した溶液をゆっくり撹拌しながら添加した
。添加が完了した時点で昇温を開始し、９０℃に到達【
ノた後、反応溶液に次亜塩素酸ナトリウム溶液（１３重
量％）１０ｇを激しく撹拌しながら徐々に添加して、黒
色の沈殿物を生成した。Example 1 8.4g of caustic soda prepared separately was added to a solution of 30g of ferrous sulfate (77km) dissolved in 6oorrl of water.
The diluted solution was slowly added with stirring. Once the addition is complete, start raising the temperature and reach 90℃ [
After that, 10 g of sodium hypochlorite solution (13% by weight) was gradually added to the reaction solution with vigorous stirring to form a black precipitate.
上記の生成した沈殿物を水洗、濾過および乾燥すること
によって、微細な粉末を得た。この粉末は、Ｘ線回折に
よりＦｅ３Ｏ４であることを確認した。また、粉末の比
表面積は、ＢＥＴ法の測定で５４．３ｔ／／ｇであった
。電子顕微鏡による観察ではほぼ球形で０．０２〜０．
Ｏｆ’１７１ｍの粒径な持っていた。A fine powder was obtained by washing the precipitate produced above with water, filtering and drying. This powder was confirmed to be Fe3O4 by X-ray diffraction. Further, the specific surface area of the powder was 54.3 t//g as measured by the BET method. When observed using an electron microscope, it is approximately spherical and has a diameter of 0.02 to 0.
It had a grain size of 171m.
実施例２
塩化コバルト（６水和）：（Ｏｇを水６００ ｍ 、Ｑ
に溶解した溶液に、別に用意した苛性ソーダ１０ｇを水
１００ｍ艷に溶解した溶液を撹拌しながら徐々に添加す
ることによって、白色の沈殿物を生成した。次いで、こ
の反応液を加熱して９０℃に昇温した後、次亜塩素酸ナ
トリウム（１３重量％）４０ｇを激しく撹拌しながら、
徐々に添加することによって、沈殿物が黒色に変化した
。この生成した沈殿物を水洗、濾過および乾燥して、微
細な粉末を得た。Example 2 Cobalt chloride (hexahydrate): (Og to 600 m of water, Q
A separately prepared solution of 10 g of caustic soda dissolved in 100 m of water was gradually added to the solution with stirring to form a white precipitate. Next, after heating this reaction solution to 90° C., 40 g of sodium hypochlorite (13% by weight) was added with vigorous stirring.
With gradual addition, the precipitate turned black. The resulting precipitate was washed with water, filtered and dried to obtain a fine powder.
上記の粉末は、Ｘ線回折の結果からＣｏ ＯＯ１１であ
ることが判明した。また、１３Ｅ Ｔ法により比表面積
のを測定した結果、８８．４ぜ７ｇであった。The above powder was found to be Co OO11 from the results of X-ray diffraction. Further, the specific surface area was measured by the 13ET method and was 88.4.7 g.
さらに、上記の粉末を大気中で、ａ ００℃で５分間、
熱処理をした。得られた粉末は、Ｘ線回折によりＣｏ３
Ｏ４であることを確認し、ＦｌＦＴ法の測定により比表
面積は９０．２イ／ｇＴ！あった。Furthermore, the above powder was heated in the atmosphere at a temperature of 00°C for 5 minutes.
Heat treated. The obtained powder was determined to be Co3 by X-ray diffraction.
It was confirmed that it was O4, and the specific surface area was determined to be 90.2 I/gT by measurement using the FlFT method! there were.
実施例３
塩化第１スズ（２水塩）３０ｇを水６００ｍ見に溶解し
た溶液に、別に用意した苛性ソーダ８゜９ｇを水１００
ｍ込に溶解した水溶液を撹拌しながら徐々に添加した結
果、白色の沈殿物を得た。Example 3 To a solution of 30 g of stannous chloride (dihydrate) dissolved in 600 m of water, 8°9 g of caustic soda prepared separately was added to 100 m of water.
As a result of gradually adding the aqueous solution dissolved in the mixture with stirring, a white precipitate was obtained.
次いでこの反応液を加熱して８０℃に昇温させた後、次
亜塩素酸カリウム水溶液（７重量％）５０ｇを可成り激
しく撹拌しながら徐々に添加した結果沈殿物は黄色に変
化した。Next, this reaction solution was heated to 80° C., and then 50 g of an aqueous potassium hypochlorite solution (7% by weight) was gradually added with fairly vigorous stirring, resulting in the precipitate turning yellow.
上記の沈殿物を水洗、濾過および乾燥して、微細な粉末
を得た。この粉末は、Ｘ線回折ではピークが現れず全く
ブロードであり、非晶質であることが認められた。また
、ＢＥＴ法による比表面積の測定では、９１．４＆／ｇ
であった。The above precipitate was washed with water, filtered and dried to obtain a fine powder. This powder was completely broad with no peaks appearing in X-ray diffraction, and was recognized to be amorphous. In addition, in the measurement of the specific surface area by the BET method, 91.4&/g
Met.
さらに、上記の粉末を大気中で、３００℃で１０分間焼
成した。得られた粉末は、Ｘ線回折により５ｎ０２であ
ることが確認され、Ｂ’ＥＴ法の測定により、比表面積
ｓ２ｒｔｒ１ｇであった。Furthermore, the above powder was fired at 300° C. for 10 minutes in the air. The obtained powder was confirmed to be 5n02 by X-ray diffraction, and the specific surface area was s2rtr1g by measurement by B'ET method.
実施例４
塩化マンガン（４水和物）３０ｇを水６００ｍ込に溶解
した水溶液に、別に用意した可性ソーダ１２ｇを水１０
０ｍ見に溶解した水溶液を添加した以外は、実施例１と
同一に実施することによって、＋Ａ８色の微細な粉末を
得た。Example 4 To an aqueous solution of 30 g of manganese chloride (tetrahydrate) dissolved in 600 m of water, 12 g of separately prepared sodium chloride was added to 10 g of water.
A fine powder of +A8 color was obtained by carrying out the same procedure as in Example 1 except that a dissolved aqueous solution was added at 0 m.
この粉末は、Ｘ線回折によりＭ ｎ ３０４であること
を確認した。また、ＢＥＴ法の測定により、比表面積は
７４．４イ／ｇであった。This powder was confirmed to be M n 304 by X-ray diffraction. Further, the specific surface area was found to be 74.4 i/g by measurement using the BET method.
Claims (1)
生成物を焼成することを特徴とする微小な金属酸化物粒
子の製造方法。1) A method for producing minute metal oxide particles, which comprises subjecting a metal hydroxide to an oxidation reaction in an aqueous solution and, if necessary, calcining the product.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18741585A JPS6252129A (en) | 1985-08-28 | 1985-08-28 | Production of fine metal oxide particle |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18741585A JPS6252129A (en) | 1985-08-28 | 1985-08-28 | Production of fine metal oxide particle |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS6252129A true JPS6252129A (en) | 1987-03-06 |
Family
ID=16205640
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP18741585A Pending JPS6252129A (en) | 1985-08-28 | 1985-08-28 | Production of fine metal oxide particle |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6252129A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0816457A3 (en) * | 1996-06-27 | 1999-06-30 | Fujitsu Limited | Slurry using Mn oxide abrasives and fabrication process of a semiconductor device using such a polishing slurry |
| US5938979A (en) * | 1997-10-31 | 1999-08-17 | Nanogram Corporation | Electromagnetic shielding |
| WO2000048939A1 (en) * | 1999-02-16 | 2000-08-24 | European Community, Represented By The Commission Of The European Communities | Precipitation process |
| US6159858A (en) * | 1995-07-04 | 2000-12-12 | Fujitsu Limited | Slurry containing manganese oxide and a fabrication process of a semiconductor device using such a slurry |
| JP2002137922A (en) * | 2000-08-31 | 2002-05-14 | Osram Sylvania Inc | Heterogenite substance for making submicron scale cobalt powder |
-
1985
- 1985-08-28 JP JP18741585A patent/JPS6252129A/en active Pending
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6159858A (en) * | 1995-07-04 | 2000-12-12 | Fujitsu Limited | Slurry containing manganese oxide and a fabrication process of a semiconductor device using such a slurry |
| EP0816457A3 (en) * | 1996-06-27 | 1999-06-30 | Fujitsu Limited | Slurry using Mn oxide abrasives and fabrication process of a semiconductor device using such a polishing slurry |
| US5938979A (en) * | 1997-10-31 | 1999-08-17 | Nanogram Corporation | Electromagnetic shielding |
| US6080337A (en) * | 1997-10-31 | 2000-06-27 | Nanogram Corporation | Iron oxide particles |
| WO2000048939A1 (en) * | 1999-02-16 | 2000-08-24 | European Community, Represented By The Commission Of The European Communities | Precipitation process |
| US6811758B1 (en) | 1999-02-16 | 2004-11-02 | European Community, Represented By The Commision Of The European Communities | Precipitation process |
| JP2002137922A (en) * | 2000-08-31 | 2002-05-14 | Osram Sylvania Inc | Heterogenite substance for making submicron scale cobalt powder |
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