JPH0832902B2 - Manufacturing method of iron nitride fine particle colloid - Google Patents
Manufacturing method of iron nitride fine particle colloidInfo
- Publication number
- JPH0832902B2 JPH0832902B2 JP9517890A JP9517890A JPH0832902B2 JP H0832902 B2 JPH0832902 B2 JP H0832902B2 JP 9517890 A JP9517890 A JP 9517890A JP 9517890 A JP9517890 A JP 9517890A JP H0832902 B2 JPH0832902 B2 JP H0832902B2
- Authority
- JP
- Japan
- Prior art keywords
- reaction
- iron nitride
- fine particle
- iron
- precursor
- 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 - Lifetime
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/44—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of magnetic liquids, e.g. ferrofluids
- H01F1/442—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of magnetic liquids, e.g. ferrofluids the magnetic component being a metal or alloy, e.g. Fe
Description
【発明の詳細な説明】 （産業上の利用分野） この発明は、鉄窒化物の微粒子コロイドの製造法に関
するものである。さらに詳しくは、この発明は、均一粒
子径を有し、分散性にも優れた、磁性流体等としての窒
化鉄微粒子コロイドを製造することのできる新しい製造
方法に関するものである。TECHNICAL FIELD The present invention relates to a method for producing a fine particle colloid of iron nitride. More specifically, the present invention relates to a new production method capable of producing an iron nitride fine particle colloid as a magnetic fluid or the like, which has a uniform particle size and is excellent in dispersibility.
（従来の技術とその課題） 従来より、窒化鉄の微粒子や磁性流体を合成する方法
として、プラズマCVD法が知られている。この方法は、
たとえばN2ガスのグロー放電プラズマ中に、たとえばFe
（CO）５蒸気を導入し、プラズマにより励起されたN2分
子と、Fe（CO）５分子がプラズマ中で分解されたFe原子
とを反応させて、窒化鉄微粒子を生成させ、これを界面
活性剤を含んだ油性媒体に取り込み磁性流体を製造す
る。また、この反応を合理的、かつ効率的に行なうため
のプラズマCVD装置も開発されている。しかしながら、
この方法は広い応用範囲を持っているものの、電離した
低圧の気体であるグロー放電プラズマ中で反応が進行
し、気相中で形成され窒化鉄微粒子は、気相中を拡散し
て反応容器内壁に到達するまでの間に相互に衝突を繰り
返しながら融合成長を続けるため、結果的に、微粒子の
サイズは統計的な広い分布を持ち、均一なサイズの微粒
子系が得られにくいという欠点がある。(Prior Art and Problems Thereof) A plasma CVD method has been conventionally known as a method for synthesizing iron nitride fine particles and magnetic fluid. This method
For example, in a glow discharge plasma of N 2 gas, for example, Fe
Introducing (CO) 5 vapor, reacting N 2 molecules excited by plasma with Fe atoms decomposed in the plasma by Fe (CO) 5 molecules to generate iron nitride fine particles, which are interfaced. The ferrofluid is produced by incorporating it into an oily medium containing an activator. Also, a plasma CVD apparatus has been developed to carry out this reaction rationally and efficiently. However,
Although this method has a wide range of applications, the reaction proceeds in glow discharge plasma, which is an ionized, low-pressure gas, and the iron nitride fine particles formed in the gas phase diffuse in the gas phase and form the inner wall of the reaction vessel. Since the fusion growth continues while repeatedly colliding with each other until reaching, the particle size has a statistically wide distribution, and as a result, it is difficult to obtain a uniformly sized particle system.
窒化鉄磁性流体等の微粒子コロイドを合成するもう一
つの方法として、この発明の発明者らによって確立され
た気相液相反応法が存在する。この方法は、たとえば鉄
カーボニルFe（CO）５のような遷移金属カーボニルと界
面活性剤の非水溶液にアンモニアガスNH3を流入しなが
ら加熱し、非水溶液中に窒化鉄等の窒化金属微粒子を生
成させる方法である。この方法では、溶液中で微粒子の
核形成と成長が行われるため、先のプラズマCVD法によ
るものに比べ、微粒子のサイズがはるかに均一である。As another method for synthesizing fine particle colloid such as iron nitride magnetic fluid, there is a gas phase liquid phase reaction method established by the inventors of the present invention. In this method, for example, a transition metal carbonyl such as iron carbonyl Fe (CO) 5 and a surfactant are heated while flowing ammonia gas NH 3 into a non-aqueous solution to form fine particles of metal nitride such as iron nitride in the non-aqueous solution. It is a method to let. In this method, since nucleation and growth of fine particles are performed in the solution, the size of the fine particles is much more uniform than that obtained by the plasma CVD method.
しかしながら、この方法を用いる場合にも、高密度の
窒化鉄微粒子コロイド、たとえば高飽和磁化の窒化金属
磁性流体を得ようとして遷移金属カーボニルを高濃度に
溶解した溶液を出発原料として用いる際には、微粒子径
が極端に大きく、かつ不揃いになることがあるという欠
点があった。この欠点は高濃度コロイド微粒子の分散安
定性を著しく損う原因となっていた。However, even when this method is used, when using a solution in which a transition metal carbonyl is dissolved at a high concentration in order to obtain a high-density iron nitride fine particle colloid, for example, a metal nitride magnetic fluid with high saturation magnetization, as a starting material, There are drawbacks that the particle size is extremely large and sometimes irregular. This defect has been a cause of markedly impairing the dispersion stability of high-concentration colloidal fine particles.
事実、この方法は高濃度微粒子コロイドの製造には不
向きであった。そのため、この方法によってあえて高濃
度の微粒子コロイドや、高飽和磁化の磁性流体を得よう
とするときには、いったん低濃度のコロイドを合成した
後に、溶媒を蒸発させてコロイド濃縮するなどの２段階
のプロセスを必要とした。In fact, this method was not suitable for the production of highly concentrated fine particle colloids. Therefore, in order to obtain a high-concentration fine particle colloid or a magnetic fluid with a high saturation magnetization by this method, a low-concentration colloid is first synthesized and then the solvent is evaporated to concentrate the colloid. Needed.
（課題を解決するための手段） この発明は従来の気相液相反応法、すなわち遷移金属
カーボニルと界面活性剤とを含んだ溶媒に含窒素化合物
を導入して加熱反応させる窒化金属の微粒子コロイドの
製造法と、この微粒子コロイドの一種としての磁性流体
を得る方法において、上記の欠点を解消し、低濃度では
もちろんのこと、高濃度の窒化鉄微粒子コロイドや、高
濃度の窒化鉄磁性流体を得ようとする場合にも、微粒子
径を小さく、かつ、きわめて均一に揃えて製造すること
のできる、簡便かつ合理的な方法を提供することを目的
としている。(Means for Solving the Problems) The present invention is a conventional gas-phase liquid phase reaction method, that is, a fine particle colloid of metal nitride in which a nitrogen-containing compound is introduced into a solvent containing a transition metal carbonyl and a surfactant to cause a heat reaction. In the production method of and the method of obtaining a magnetic fluid as a kind of this fine particle colloid, the above-mentioned drawbacks are solved, and not only a low concentration but also a high concentration iron nitride fine particle colloid and a high concentration iron nitride magnetic fluid can be used. It is an object of the present invention to provide a simple and rational method in which even when an attempt is made to obtain the particles, the diameter of the particles can be made small and the particles can be produced extremely uniformly.
すなわち、この発明は、鉄カーボニルとアンモニアと
の接触反応による窒化鉄微粒子コロイドの製造法におい
て、前駆物質である含窒素カーボニル化合物を合成する
ための前段反応と、その前駆物質から窒化鉄を合成する
後段反応との２段階の反応を行うことを特徴とする微粒
子コロイドの製造法を提供する。That is, in the present invention, in a method for producing an iron nitride fine particle colloid by a catalytic reaction between iron carbonyl and ammonia, a pre-stage reaction for synthesizing a nitrogen-containing carbonyl compound as a precursor and iron nitride are synthesized from the precursor. Provided is a method for producing a fine particle colloid, which comprises performing a two-step reaction with a second-step reaction.
この発明は、次のような反応機構の解明に基づいて構
成されている。The present invention is constructed based on the clarification of the following reaction mechanism.
まず明らかにしたことは、気相液相反応においては、
反応式（１）〜（３）で示すように、鉄カーボニルがア
ンモニアと反応して前駆体である鉄アンミンカーボニル
化物Fe（CO）１（NHm）ｎを形成し、それが順次分解
し、窒化鉄微粒子を生成することである。The first clarification is that in the gas-phase liquid-phase reaction,
As shown in reaction formulas (1) to (3), iron carbonyl reacts with ammonia to form a precursor iron ammine carbonyl compound Fe (CO) 1 (NH m ) n , which is sequentially decomposed, This is to produce iron nitride fine particles.
3Fe（CO）５＋2NH3→ Fe3（CO）９（NH）２＋6CO＋2H2 （１） 2Fe3（CO）９（NH）２＋2NH3＋H2→ 3Fe2（CO）６（NH2）２ （２） 3Fe2（CO）６（NH2）２→2Fe3N＋18CO＋4NH3 （３） 前駆体が形成される反応式（１）〜（２）は反応槽温
度が70℃以上で顕著であり、一方、前駆体から窒化鉄が
生成する反応（３）は120℃以上で顕著である。3Fe (CO) 5 + 2NH 3 → Fe 3 (CO) 9 (NH) 2 + 6CO + 2H 2 (1) 2Fe 3 (CO) 9 (NH) 2 + 2NH 3 + H 2 → 3Fe 2 (CO) 6 (NH 2 ) 2 ( 2) 3Fe 2 (CO) 6 (NH 2 ) 2 → 2Fe 3 N + 18CO + 4NH 3 (3) The reaction formulas (1) to (2) in which the precursor is formed are remarkable when the reaction tank temperature is 70 ° C. or higher. The reaction (3) in which iron nitride is produced from the precursor is remarkable at 120 ° C. or higher.
しかしながら、これらの反応と並行して次の（４）〜
（６）式で示すようにFe（CO）５がNH3との反応を経由
することなく直接に分解する反応も同時に進行しやす
い。However, in parallel with these reactions, the following (4)-
As shown in the formula (6), the reaction of directly decomposing Fe (CO) 5 without passing through the reaction with NH 3 is likely to proceed at the same time.
2Fe（CO）５→Fe2（CO）９＋CO （４） 3Fe2（CO）９→2Fe3（CO）12＋3CO （５） Fe3（CO）12→3Fe＋12CO （６） 100℃以上の温度でおこるこの反応（４）〜（６）は
従来からよく知られている反応であって、生成されるFe
は一般に非晶質鉄ａ−Feである。2Fe (CO) 5 → Fe 2 (CO) 9 + CO (4) 3Fe 2 (CO) 9 → 2Fe 3 (CO) 12 + 3CO (5) Fe 3 (CO) 12 → 3Fe + 12CO (6) At a temperature of 100 ° C or higher The reactions (4) to (6) that take place are well known in the art, and the Fe produced is
Is generally amorphous iron a-Fe.
したがって、120℃以上の温度に加熱した時、Fe（C
O）５が存在すると目的とするFeaNの他に必ずａ−Feが
副生されることになる。その結果、窒化鉄の反応収率が
低くなる。しかも混在したａ−Feは磁性流体全体の化学
的安定性をも損なうばかりか、ａ−FeがFe3N微粒子の表
面に沿って析出するため、Fe3N微粒子どうしが焼結し、
その結果微粒子粗大なものとなって、磁性流体は分散安
定生を失うことになる。Therefore, when heated to a temperature of 120 ° C or higher, Fe (C
When O) 5 is present, a-Fe is always produced as a by-product in addition to the desired Fe a N. As a result, the reaction yield of iron nitride decreases. Moreover not only is mixed-a-Fe also impair the chemical stability of the entire magnetic fluid, for a-Fe precipitates along the surface of the Fe 3 N particles, Fe 3 N particles each other is sintered,
As a result, the particles become coarse and the magnetic fluid loses dispersion stability.
そこで、この発明の発明者らは、鋭意研究の結果、副
反応（４）をおさえ、主反応（１）〜（３）のみを起こ
させるよう製造法を構成することにより、上記の問題が
解決されることを見出し、この発明を完成した。Therefore, as a result of earnest research, the inventors of the present invention have solved the above-mentioned problem by configuring the production method so as to suppress the side reaction (4) and cause only the main reactions (1) to (3). The present invention has been completed and the present invention has been completed.
すなわち、この発明は、鉄カーボニルを用いる場合に
は、100℃より低い温度で前駆物質を合成し、これに続
いて120℃以上のより高い温度で前駆物質から窒化鉄を
合成するという２段階の反応操作を行うことを特徴と
し、かつ、両者の間に未反応のFe（CO）５を除去するた
めの適切なプロセスを挿入することをも具体的な特徴と
している。未反応FE（CO）５除去方法としては、前駆物
質の合成反応終了後の反応生成物を減圧蒸留することが
有効な方法としてあげられる。また、高濃度のコロイド
を得ようとする場合には、上記のプロセスを多数回繰り
返して行うことが有効な方法としてあげられる。That is, the present invention is a two-step process in which, when iron carbonyl is used, a precursor is synthesized at a temperature lower than 100 ° C., and then iron nitride is synthesized from the precursor at a higher temperature of 120 ° C. or higher. It is characterized by carrying out a reaction operation, and is also characterized by inserting an appropriate process for removing unreacted Fe (CO) 5 between them. As a method of removing unreacted FE (CO) 5, it is effective to distill the reaction product after the completion of the precursor synthesis reaction under reduced pressure. Further, in order to obtain a high-concentration colloid, it is effective to repeat the above process many times.
そしてこの発明の方法は、上記の鉄カーボニルの場合
に限定されることはない。Ni、Co、Ｗ、Mo等の任意の遷
移金属のカーボニルをも適用対象とすることができる。
また、その種類に応じて、上記の温度等の操作条件を変
更することができる。And the method of the present invention is not limited to the above-mentioned iron carbonyl. Carbonyl of any transition metal such as Ni, Co, W, and Mo can also be applied.
In addition, the operating conditions such as the above temperature can be changed according to the type.
次に実施例を示し、さらに詳しくこの発明について説
明する。Next, the present invention will be described in more detail with reference to examples.
（実施例） 50グラムのケロシンに、界面活性剤として23.6グラム
のＮ−テトラエチレンテトラアミノポリブテニルこはく
酸イミド（分子量は約1300）を溶解し、次いで鉄カーボ
ニル（Fe（CO）５）170.5グラムを添加した反応溶液を
撹拌装置を取付けた耐熱ガラス製反応容器に入れ、アン
モニアガスNH3を390cc/分の割合で反応溶液に導入しな
がら、まず80℃に１時間加熱し、前駆物質である鉄アン
ミンカーボニル化合物を合成した。その後、未反応のFe
（CO）５を減圧蒸留し、別の容器にそれを捕集したうえ
で、残りの反応容器を130℃の温度に１時間加熱した。
さらに先に捕集していたFe（CO）５を再び反応容器に添
加し、以下同様なプロセスを合計４回繰り返して行うこ
とにより、170.5グラムのFe（CO）５すべてを消費して
全反応を終結させた。Example: In 50 grams of kerosene, 23.6 grams of N-tetraethylenetetraaminopolybutenyl succinimide (molecular weight about 1300) was dissolved as a surfactant, then iron carbonyl (Fe (CO) 5 ) 170.5 The reaction solution containing gram was placed in a heat-resistant glass reaction vessel equipped with a stirrer, and ammonia gas NH 3 was introduced into the reaction solution at a rate of 390 cc / min. An iron ammine carbonyl compound was synthesized. Then unreacted Fe
(CO) 5 was distilled under reduced pressure, collected in another vessel, and the remaining reaction vessel was heated to a temperature of 130 ° C. for 1 hour.
The Fe (CO) 5 collected earlier was added to the reaction vessel again, and the same process was repeated 4 times in total to consume 170.5 g of all Fe (CO) 5 for the entire reaction. Ended.
得られた窒化鉄コロイドはFe3NとFe4N相の良好な結晶
型を有する微粒子からなっており、窒化物としての収率
はほぼ100％であった。また微粒子の大きさは均一であ
り、その平均粒径は6.5ナノメーターで、±0.5ナノメー
ターの範囲に微粒子の約60％が含まれていた。The obtained iron nitride colloid consisted of fine particles of Fe 3 N and Fe 4 N phases having good crystal forms, and the yield as a nitride was almost 100%. The size of the particles was uniform, and the average particle size was 6.5 nanometers, and about 60% of the particles were included in the range of ± 0.5 nanometer.
（発明の効果） 以上詳しく説明した通り、この発明の方法によって、 １）粒径のよく揃った微粒子コロイドとしての窒化鉄微
粒子等が得られるので、大きい磁化をもつ磁性流体が得
られる。(Effects of the Invention) As described in detail above, according to the method of the present invention, 1) iron nitride fine particles or the like as fine particle colloids having a uniform particle size can be obtained, so that a magnetic fluid having a large magnetization can be obtained.
２）分散性がよく、凝集しにくい微粒子コロイドとして
の磁性流体等のコロイドが得られる、 ３）粘性が小さく、流動性に富んだ磁性流体等が得られ
る、 ４）磁性体微粒子が酸化されにくく、湿潤な大気中でも
化学的に安定な磁性流体等のコロイドが得られる、 等の技術的効果が実現される。2) A colloid such as a magnetic fluid is obtained as a fine particle colloid that has good dispersibility and does not easily agglomerate. 3) A magnetic fluid having a low viscosity and a high fluidity is obtained. 4) The magnetic fine particles are hard to be oxidized. Technical effects such as obtaining a chemically stable colloid such as a magnetic fluid even in a humid atmosphere can be realized.
さらには、この発明により、 １）製造に高価な装置、設備を必要としない、 ２）製造に高度な知識や高度な技術を必要としない、 ３）原料が安価である、 ４）製造工程の工程数が少ない、 ５）単位時間当たりの生産量が大きい、 ６）有毒物の発生がない、 等の優れた経済的効果が実現される。 Furthermore, according to the present invention, 1) no expensive equipment or facility is required for manufacturing, 2) neither advanced knowledge nor advanced technology is required for manufacturing, 3) raw materials are cheap, 4) manufacturing process Excellent economic effects such as a small number of steps, 5) large production per unit time, 6) no generation of toxic substances, etc. are realized.
───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.6 識別記号 庁内整理番号 ＦＩ 技術表示箇所 // Ｃ１０Ｎ 10:16 20:06 Ｚ 40:14 70:00 ─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. 6 Identification code Office reference number FI technical display location // C10N 10:16 20:06 Z 40:14 70:00
Claims (5)
窒化鉄微粒子コロイドを製造する方法において、前駆物
質の含窒素鉄カーボニル化合物を合成する前段反応と、
その前駆物質から窒化鉄を合成する後段反応との２段階
の反応操作を行うことを特徴とする窒化鉄微粒子コロイ
ドの製造法。1. A method for producing an iron nitride fine particle colloid by the reaction of iron carbonyl and ammonia, which comprises a pre-stage reaction for synthesizing a nitrogen-containing iron carbonyl compound as a precursor,
A method for producing an iron nitride fine particle colloid, which comprises performing a two-step reaction operation including a post-step reaction for synthesizing iron nitride from the precursor.
を合成するための前段反応と、その前駆物質から窒化鉄
を合成する後段反応の２段階の反応を小刻みに複数回繰
り返すことを特徴とする請求項（１）記載の製造法。2. A front-end reaction for synthesizing a nitrogen-containing iron carbonyl compound as a precursor, and a rear-end reaction for synthesizing iron nitride from the precursor, which is a two-step reaction repeated in small steps. The manufacturing method according to claim 1.
る請求項（１）記載の製造法。3. The method according to claim 1, wherein the temperature of the second-stage reaction is lower than 100 ° C.
る請求項（１）記載の製造法。4. The method according to claim 1, wherein the temperature of the second-stage reaction is higher than 120 ° C.
ーボニルを除去する工程を設ける請求項（１）記載の製
造法。5. The production method according to claim 1, wherein a step of removing unreacted iron carbonyl is provided between the first-stage reaction and the second-stage reaction.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9517890A JPH0832902B2 (en) | 1990-04-12 | 1990-04-12 | Manufacturing method of iron nitride fine particle colloid |
| US07/684,387 US5180512A (en) | 1990-04-12 | 1991-04-12 | Method of manufacturing fine-particle colloid or magnetic fluid |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9517890A JPH0832902B2 (en) | 1990-04-12 | 1990-04-12 | Manufacturing method of iron nitride fine particle colloid |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0570784A JPH0570784A (en) | 1993-03-23 |
| JPH0832902B2 true JPH0832902B2 (en) | 1996-03-29 |
Family
ID=14130497
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9517890A Expired - Lifetime JPH0832902B2 (en) | 1990-04-12 | 1990-04-12 | Manufacturing method of iron nitride fine particle colloid |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0832902B2 (en) |
-
1990
- 1990-04-12 JP JP9517890A patent/JPH0832902B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0570784A (en) | 1993-03-23 |
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