JP3207070B2 - Method for producing ruthenium dioxide powder - Google Patents
Method for producing ruthenium dioxide powderInfo
- Publication number
- JP3207070B2 JP3207070B2 JP04773095A JP4773095A JP3207070B2 JP 3207070 B2 JP3207070 B2 JP 3207070B2 JP 04773095 A JP04773095 A JP 04773095A JP 4773095 A JP4773095 A JP 4773095A JP 3207070 B2 JP3207070 B2 JP 3207070B2
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- ruthenium
- ruthenium dioxide
- powder
- dioxide powder
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- 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.)
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Description
【０００１】[0001]
【産業上の利用分野】本発明は二酸化ルテニウム粉末の
製造方法の改良に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a method for producing ruthenium dioxide powder.
【０００２】[0002]
【従来の技術】従来二酸化ルテニウムを製造するには、
塩化ルテニウム酸水溶液を出発物質とし、これをアンモ
ニア水で中和して水酸化ルテニウムの微粒子を調製し、
得られた微粒子を洗浄、乾燥して二酸化ルテニウム粉末
を得ている。（特開平２−８８４３１号、特開平２−８
８４３２号公報） また熱分解による方法として、塩化ルテニウム水溶液に
硝酸を加えて蒸発乾固させ、これを 350℃乃至 370℃に
て熱分解し、さらに 500℃乃至 550℃に保持して二酸化
ルテニウム粉末を得る方法がある。（Ｇ．Ｃ．Ｂｏｎ
ｄ、ｅｔａｌ Ｐｒｏｃ．ｃｈｅｍ．ｓｏｃ．１９６
４、３９８） ところで上記いずれの方法も出発物質としてＣｌイオン
を含有する塩化ルテニウム（ＲｕＣｌ3 ）を用いている
が、一度混入したＣｌイオンを除去することは非常に困
難である為、なるべく塩素含有量の少ない材料より出発
することがＣｌイオンの少ない二酸化ルテニウム粉末を
作る為には有効である。特に二酸化ルテニウム粉末を触
媒として用いる際、Ｃｌイオンを僅かでも含有している
と有害であり、またエレクトロニクス材料例えば厚膜抵
抗ペースト用導電粒子としてはＣｌイオンの少ないもの
が求められている。また上記いずれの方法によって得ら
れた二酸化ルテニウム粉末も、比表面積が小さく、表面
活性が弱い為、触媒には利用し得なかった。2. Description of the Related Art Conventionally, to produce ruthenium dioxide,
A ruthenium chloride aqueous solution was used as a starting material, and this was neutralized with aqueous ammonia to prepare ruthenium hydroxide fine particles,
The obtained fine particles are washed and dried to obtain a ruthenium dioxide powder. (JP-A-2-88431, JP-A-2-8
No. 8432) In addition, as a method by thermal decomposition, a ruthenium chloride aqueous solution is added with nitric acid and evaporated to dryness, thermally decomposed at 350 ° C. to 370 ° C., and further maintained at 500 ° C. to 550 ° C. to obtain ruthenium dioxide powder. There is a way to get (GC Bon
d, et al Proc. chem. soc. 196
4, 398) By the way, in each of the above methods, ruthenium chloride (RuCl 3 ) containing Cl ions is used as a starting material. However, since it is very difficult to remove Cl ions once mixed, it is preferable to use chlorine-containing materials. Starting from a lesser amount of material is effective for making ruthenium dioxide powder with less Cl ions. In particular, when using ruthenium dioxide powder as a catalyst, it is harmful to contain even a small amount of Cl ions, and there is a demand for electronic materials such as conductive particles for thick-film resistance pastes that contain a small amount of Cl ions. Also, the ruthenium dioxide powder obtained by any of the above methods could not be used as a catalyst because of its small specific surface area and low surface activity.
【０００３】[0003]
【発明が解決しようとする課題】そこで本発明はＣｌイ
オンが少なく、比表面積値が大きく、表面活性の高い二
酸化ルテニウム粉末の製造方法を提供しようとするもの
である。Accordingly, an object of the present invention is to provide a method for producing a ruthenium dioxide powder having a small amount of Cl ions, a large specific surface area and a high surface activity.
【０００４】[0004]
【課題を解決するための手段】上記課題を解決するため
の本発明の二酸化ルテニウム粉末の製造方法は、硝酸ル
テニウム溶液を濃縮し、蒸発乾固した後、 160℃乃至 2
40℃の範囲内の空気雰囲気中で熱分解を行い、二酸化ル
テニウム粉末を得ることを特徴とするものである。上記
硝酸ルテニウム溶液としてはルテニウム濃度40乃至60g/
l 程度の溶液を用いるが、含有Ｃｌ量は極力少ないもの
が望まれるが、精製コスト等の関係からＣｌ 280mg/l乃
至 380mg/l程度のものが好ましい。また、濃縮は70℃乃
至90℃にて液量が１／３乃至１／４になるまで行うもの
である。さらに蒸発乾固は80℃乃至 100℃にて２時間乃
至５時間、 110℃乃至 130℃にて２時間乃至５時間、次
いで 140℃乃至 160℃にて２時間乃至５時間という三段
階の条件、順序で加熱して行うことが好ましい。また他
の本発明の二酸化ルテニウム粉末の製造方法は上記蒸発
乾固後熱分解前に予備熱分解を 190℃乃至 200℃にて３
時間乃至４時間行い、その後一旦粉砕するものである。
さらに他の本発明の二酸化ルテニウム粉末の製造方法
は、上記熱分解後得られた二酸化ルテニウム粉末をさら
に水洗、乾燥することを特徴とするものである。水洗は
アンモニア水にて中和してから行い、乾燥は70℃次いで
解砕次いで90℃で行うのが好ましい。According to the present invention, there is provided a method for producing a ruthenium dioxide powder, comprising: concentrating a ruthenium nitrate solution; evaporating the solution to dryness;
It is characterized in that pyrolysis is performed in an air atmosphere within a range of 40 ° C. to obtain a ruthenium dioxide powder. The ruthenium nitrate solution has a ruthenium concentration of 40 to 60 g /
Although a solution of about l is used, it is desired that the content of Cl is as small as possible, but from the viewpoint of purification cost and the like, a Cl of about 280 mg / l to 380 mg / l is preferable. Concentration is performed at 70 ° C. to 90 ° C. until the liquid volume is reduced to 1/3 to 1/4. Evaporation to dryness is performed at 80 ° C to 100 ° C for 2 hours to 5 hours, 110 ° C to 130 ° C for 2 hours to 5 hours, and then 140 ° C to 160 ° C for 2 hours to 5 hours. It is preferable that the heating is performed in order. Further, another method for producing ruthenium dioxide powder of the present invention is to carry out preliminary pyrolysis at 190 ° C. to 200 ° C. before pyrolysis after evaporation to dryness.
This is carried out for 1 hour to 4 hours, and then the material is once ground.
Still another method for producing a ruthenium dioxide powder according to the present invention is characterized in that the ruthenium dioxide powder obtained after the pyrolysis is further washed with water and dried. Washing with water is carried out after neutralization with aqueous ammonia, and drying is preferably carried out at 70 ° C., then crushed and then at 90 ° C.
【０００５】[0005]
【作用】本発明の二酸化ルテニウム粉末の製造方法は原
料としてＣｌイオン含有量の非常に少ない硝酸ルテニウ
ム溶液を用いているので、Ｃｌイオンによる汚染の少な
い二酸化ルテニウム粉末が得られる。また熱分解を 160
℃乃至 240℃の空気が流れている状態で行うので、分解
がゆっくりと行われ比表面積値の大きい、表面活性の高
い二酸化ルテニウム粉末が得られる。この熱分解を 160
℃未満で行うと分解が完全に進行せず、また 240℃を超
えた温度で行うと分解が速すぎ、比表面積値の小さなも
のとなってしまう。また硝酸ルテニウム溶液の濃縮、蒸
発乾固の条件も得られる二酸化ルテニウム粉末の比表面
積値へ大きく影響するものと思われる。特に蒸発固化の
条件は重要であり、上記三段階の条件で加熱、蒸発乾固
することにより、比表面積値の大きな粒子となる基礎が
作られるものである。また、固化したものの粉砕は予備
分解をしてから行うのが、均一に熱分解ができるという
理由で好ましい。また得られた二酸化ルテニウムの粉末
はさらにアンモニア水による中和、水洗、乾燥を行うと
より不純物の少ないものが得られる。Since the ruthenium dioxide powder production method of the present invention uses a ruthenium nitrate solution having a very low Cl ion content as a raw material, a ruthenium dioxide powder with little contamination by Cl ions can be obtained. In addition, thermal decomposition
Since the decomposition is carried out in a state where air at a temperature of from 240 ° C. to 240 ° C. is flowing, ruthenium dioxide powder having high specific surface area and high surface activity is obtained. This pyrolysis is 160
If the temperature is lower than 240 ° C., the decomposition will not proceed completely. If the temperature is higher than 240 ° C., the decomposition will be too fast and the specific surface area will be small. In addition, it is considered that the conditions of concentration and evaporation to dryness of the ruthenium nitrate solution greatly affect the specific surface area of the obtained ruthenium dioxide powder. In particular, the conditions for evaporation and solidification are important. By heating and evaporating to dryness under the above three conditions, a basis for forming particles having a large specific surface area is created. Further, it is preferable that the solidified material is pulverized after preliminarily decomposing it because it can be thermally decomposed uniformly. When the obtained ruthenium dioxide powder is further neutralized with aqueous ammonia, washed with water and dried, a powder having less impurities can be obtained.
【０００６】[0006]
【実施例】本発明の二酸化ルテニウム粉末の製造方法の
実施例と比較例及び従来例について説明する。EXAMPLES Examples of the method for producing ruthenium dioxide powder of the present invention, comparative examples and conventional examples will be described.
【０００７】[0007]
【実施例１】Ｒｕ 3.609wt％の硝酸ルテニウム溶液 380
ml（ 480.1ｇ）を70〜90℃で６時間かけて濃縮し、 125
mlとした。次に大型蒸発皿で手まぜし、ペースト状とし
た後、乾燥機に移し、90℃、３時間次いで 120℃３時間
次いで 150℃３時間で固化した。次いで 190℃〜 200℃
で４時間予備熱分解してコークス状とした後、メノー乳
鉢にて粉末状に粉砕した。そして 200℃、７時間かけて
本熱分解した。この時の比表面積値は 127.7m2/g、Ｒｕ
含有率70.3％であった。その後アンモニア水中和後、水
洗し、70℃で乾燥して酸化ルテニウム粉末を得た。この
酸化ルテニウム粉末の比表面積値は 125.0m2/g、Ｒｕ含
有率70.2％であった。Example 1 Ru 3.609 wt% ruthenium nitrate solution 380
ml (480.1 g) was concentrated at 70-90 ° C for 6 hours,
ml. Next, the mixture was mixed with a large evaporating dish to form a paste, transferred to a dryer, and solidified at 90 ° C. for 3 hours, then at 120 ° C. for 3 hours and then at 150 ° C. for 3 hours. Then 190 ℃ ~ 200 ℃
For 4 hours, and then pulverized into a coke-like form in an agate mortar. And this thermal decomposition was performed at 200 ° C. for 7 hours. The specific surface area value at this time is 127.7 m 2 / g, Ru
The content was 70.3%. Thereafter, the resultant was neutralized with aqueous ammonia, washed with water, and dried at 70 ° C. to obtain a ruthenium oxide powder. The specific surface area of this ruthenium oxide powder was 125.0 m 2 / g, and the Ru content was 70.2%.
【０００８】[0008]
【実施例２】Ｒｕ 3.895％の硝酸ルテニウム溶液 1.0ｌ
（1333.4ｇ）を80℃、10時間かけて濃縮し、約 250mlと
した。次に大型蒸発皿で手まぜし、ペースト状にし、さ
らにタール状にした後、乾燥機に移し、90℃、３時間次
いで 120℃、４時間次いで150℃、３時間の加熱で褐色
の気体が発生して固化した。次いで 190℃〜 200℃で３
時間予備熱分解してコークス状となした後、メノー乳鉢
にて粉末状に粉砕した。そして 200℃、17時間かけて本
熱分解した。この時の比表面積値は 119.3m2/g、Ｒｕ含
有率67.5％であった。その後アンモニア水中和後水洗
し、70℃で乾燥し、解砕し、さらに90℃で乾燥して酸化
ルテニウム粉末を得た。この酸化ルテニウム粉末の比表
面積値は 125.7m2/g、Ｒｕ含有率 67.55％であった。Example 2 Ru: 1.895% Ruthenium nitrate solution 1.0 L
(1333.4 g) was concentrated at 80 ° C. over 10 hours to about 250 ml. Next, mix with a large evaporating dish to make a paste and then a tar, transfer to a dryer, and heat at 90 ° C, 3 hours, 120 ° C, 4 hours, then 150 ° C, 3 hours to produce a brown gas. Generated and solidified. Then at 190 ~ 200 ℃ 3
After preliminarily pyrolyzing to form a coke, it was pulverized into a powder in an agate mortar. And this thermal decomposition was performed at 200 ° C for 17 hours. At this time, the specific surface area was 119.3 m 2 / g, and the Ru content was 67.5%. Thereafter, the resultant was washed with water after neutralization with aqueous ammonia, dried at 70 ° C., crushed, and further dried at 90 ° C. to obtain a ruthenium oxide powder. The specific surface area of this ruthenium oxide powder was 125.7 m 2 / g, and the Ru content was 67.55%.
【０００９】[0009]
【比較例】Ｒｕ 46.16g/l の比率の硝酸ルテニウム溶液
500mlを、65℃〜70℃で13時間かけて濃縮し、約 200ml
とした。次に大型蒸発皿で手まぜし、ペースト状とした
後、乾燥機に移し、90℃、４時間次いで 120℃、３時間
次いで 150℃、３時間で固化した。次いで 190℃で４時
間予備熱分解した後メノー乳鉢にて粉末状に粉砕した。
この時の比表面積値は 133.2m2/gで、Ｒｕ含有率64.2％
であった。またこれを水洗した後の比表面積値は 136.9
m2/g、Ｒｕ含有率62.8％であった。次いで250℃、３時
間かけて本熱分解した。この時の比表面積値は73.9m2/
g、Ｒｕ含有率73.9％であった。その後、アンモニア水
中和で水洗し、70℃で乾燥して酸化ルテニウム粉末を得
た。この酸化ルテニウム粉末の比表面積値は75.2m2/g、
Ｒｕ含有率72.4％であった。[Comparative Example] Ruthenium nitrate solution with a ratio of Ru 46.16 g / l
500 ml is concentrated at 65 ° C to 70 ° C for 13 hours, about 200 ml
And Next, the mixture was hand-mixed with a large evaporating dish to form a paste, transferred to a dryer, and solidified at 90 ° C. for 4 hours, then at 120 ° C., for 3 hours, then at 150 ° C. for 3 hours. Next, after preliminarily pyrolyzing at 190 ° C. for 4 hours, it was pulverized into a powder in an agate mortar.
At this time, the specific surface area was 133.2 m 2 / g, and the Ru content was 64.2%.
Met. The specific surface area after washing with water was 136.9.
m 2 / g, and Ru content was 62.8%. Then, the resultant was thermally decomposed at 250 ° C. for 3 hours. The specific surface area value at this time is 73.9 m 2 /
g and Ru content were 73.9%. Thereafter, the resultant was washed with neutralized aqueous ammonia and dried at 70 ° C. to obtain a ruthenium oxide powder. The specific surface area value of this ruthenium oxide powder is 75.2 m 2 / g,
The Ru content was 72.4%.
【００１０】[0010]
【従来例】塩化ルテニウム酸水溶液（Ｒｕ20g/l の比率
で含有）50mlを14％アンモニア水40ml（10ml／sec 滴
注）で中和して、水酸化ルテニウム（ｐＨ 7.7）の微粒
子を調製し、得られた微粒子を洗浄、乾燥して酸化ルテ
ニウム粉末を得た。この酸化ルテニウム粉末は、球状粒
子で、平均粒径0.15μｍ、粒度分布0.08〜0.20μｍであ
った。そして酸化ルテニウム粉末の比表面積値を調べた
処、20〜30m2/g程度であり、残存するＣｌイオン量も12
wt％と非常に多かった。以上述べた実施例１、２、比較
例、従来例で明らかなように、実施例１、２の酸化ルテ
ニウム粉末は、比較例、従来例に比べ比表面積値が大き
く、表面活性が強いことが判る。[Prior art] Ruthenium hydroxide (pH 7.7) fine particles were prepared by neutralizing 50 ml of an aqueous ruthenic chloride solution (containing 20 g / l of Ru) with 40 ml of 14% aqueous ammonia (drops of 10 ml / sec). The obtained fine particles were washed and dried to obtain a ruthenium oxide powder. This ruthenium oxide powder was spherical, having an average particle size of 0.15 μm and a particle size distribution of 0.08 to 0.20 μm. When the specific surface area of the ruthenium oxide powder was examined, it was about 20 to 30 m 2 / g, and the amount of remaining Cl ions was also 12
wt% was very high. As is clear from the above-described Examples 1 and 2, the comparative example, and the conventional example, the ruthenium oxide powders of Examples 1 and 2 have a large specific surface area and a high surface activity as compared with the comparative example and the conventional example. I understand.
【００１１】[0011]
【発明の効果】以上の説明で判るように本発明の二酸化
ルテニウム粉末の製造方法は、塩素含有量の少ない硝酸
ルテニウム溶液を出発物質とするので、Ｃｌイオンの少
ない酸化ルテニウム粉末を得ることができる。また、硝
酸ルテニウム溶液の濃縮後の蒸発乾固、熱分解において
硝酸ルテニウムの分解がゆっくりと行われるため、比表
面積値の大きい、表面活性の高い二酸化ルテニウム粉末
が得られる。As can be seen from the above description, the method for producing ruthenium dioxide powder of the present invention uses a ruthenium nitrate solution having a low chlorine content as a starting material, so that a ruthenium oxide powder having a small amount of Cl ions can be obtained. . Further, since the ruthenium nitrate is slowly decomposed in the evaporation to dryness and thermal decomposition after concentration of the ruthenium nitrate solution, a ruthenium dioxide powder having a large specific surface area and a high surface activity can be obtained.
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 昭50−103499（ＪＰ，Ａ) 特開 平５−220395（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) C01G 55/00 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-50-103499 (JP, A) JP-A-5-220395 (JP, A) (58) Fields investigated (Int. Cl. 7 , DB name) C01G 55/00
Claims (4)
した後、 160℃乃至240℃の範囲内の空気雰囲気中で熱
分解を行い、二酸化ルテニウム粉末を得ることを特徴と
する二酸化ルテニウム粉末の製造方法。1. A ruthenium nitrate powder, comprising: concentrating a ruthenium nitrate solution, evaporating to dryness, and thermally decomposing the ruthenium dioxide powder in an air atmosphere at a temperature in the range of 160 ° C. to 240 ° C. Production method.
間乃至５時間、 110℃乃至 130℃にて２時間乃至５時
間、次いで 140℃乃至 160℃にて２時間乃至５時間とい
う三段階の条件、順序で加熱して行うことを特徴とする
請求項１記載の二酸化ルテニウム粉末の製造方法。2. The evaporation to dryness is performed at 80 ° C. to 100 ° C. for 2 hours to 5 hours, at 110 ° C. to 130 ° C. for 2 hours to 5 hours, and then at 140 ° C. to 160 ° C. for 2 hours to 5 hours. three-step condition, the manufacturing method of ruthenium dioxide powder according to claim 1 Symbol placement and performing by heating in the order.
を 190℃乃至 200℃にて３乃至４時間行い、その後一旦
粉砕することを特徴とする請求項１又は２記載の二酸化
ルテニウム粉末の製造方法。After wherein said dryness, the pre-pyrolysis before pyrolysis is performed 3 to 4 hours at 190 ° C. to 200 ° C., ruthenium dioxide according to claim 1 or 2, wherein thereafter once said grinding Powder manufacturing method.
ムの粉末をさらに水洗、乾燥することを特徴とする請求
項１、２又は３記載の二酸化ルテニウム粉末の製造方
法。4. After the pyrolysis, powder washed in water of the resulting ruthenium dioxide, dried claim 1, 2 or 3 manufacturing method of ruthenium dioxide powder, wherein that.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP04773095A JP3207070B2 (en) | 1995-02-13 | 1995-02-13 | Method for producing ruthenium dioxide powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP04773095A JP3207070B2 (en) | 1995-02-13 | 1995-02-13 | Method for producing ruthenium dioxide powder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH08217459A JPH08217459A (en) | 1996-08-27 |
| JP3207070B2 true JP3207070B2 (en) | 2001-09-10 |
Family
ID=12783465
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP04773095A Expired - Fee Related JP3207070B2 (en) | 1995-02-13 | 1995-02-13 | Method for producing ruthenium dioxide powder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3207070B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3479463B2 (en) * | 1999-01-29 | 2003-12-15 | 太陽インキ製造株式会社 | Photocurable conductive composition and plasma display panel formed with electrodes using the same |
| JP5792099B2 (en) * | 2012-03-02 | 2015-10-07 | 田中貴金属工業株式会社 | Method for producing aqueous ruthenium nitrate solution |
-
1995
- 1995-02-13 JP JP04773095A patent/JP3207070B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH08217459A (en) | 1996-08-27 |
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