JPH0635329B2 - Method for producing zirconium oxide powder - Google Patents
Method for producing zirconium oxide powderInfo
- Publication number
- JPH0635329B2 JPH0635329B2 JP59205950A JP20595084A JPH0635329B2 JP H0635329 B2 JPH0635329 B2 JP H0635329B2 JP 59205950 A JP59205950 A JP 59205950A JP 20595084 A JP20595084 A JP 20595084A JP H0635329 B2 JPH0635329 B2 JP H0635329B2
- Authority
- JP
- Japan
- Prior art keywords
- zirconium
- added
- oxide
- hydroxide
- water
- 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
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Description
【発明の詳細な説明】 本発明は部分安定化酸化ジルコニウム粉体の製造方法に
関するものであり、更に詳細には中和共沈法により水酸
化ジルコニウムを析出せしめるに当たり、種子として少
量の水酸化ジルコニウムを添加することを特徴とする酸
化ジルコニウム粉体の製造方法に関するものである。The present invention relates to a method for producing a partially stabilized zirconium oxide powder, and more specifically, in depositing zirconium hydroxide by a neutralization coprecipitation method, a small amount of zirconium hydroxide as seeds is used. And a method for producing a zirconium oxide powder.
近年部分安定化酸化ジルコニウム粉体は高強度、高靭性
の酸化ジルコニウム成形体が広範な分野において使用さ
れるようになったため種々その製造方法が検討されてい
る。この部分安定化酸化ジルコニウム粉体の製造方法と
しては、水溶性ジルコニウム化合物にイットリウム、
マグネシウム、セリウム、カルシウム等の化合物を安定
化剤として加え、次いでアルカリで中和処理した後濾
過、水洗し、乾燥、焼成する方法、オキシ塩化ジルコ
ニウムまたはジルコニウムアルコキシドに安定化剤を加
え、加水分解させて得た水酸化物を乾燥、焼成する方
法、等がある。In recent years, the partially stabilized zirconium oxide powder has been used in a wide range of fields for high-strength and high-toughness zirconium oxide compacts, and various manufacturing methods thereof have been investigated. As a method for producing this partially stabilized zirconium oxide powder, yttrium is added to the water-soluble zirconium compound,
A compound such as magnesium, cerium, or calcium is added as a stabilizer, and then neutralized with an alkali, followed by filtration, washing with water, drying, and firing. A stabilizer is added to zirconium oxychloride or zirconium alkoxide to cause hydrolysis. There is a method of drying and baking the obtained hydroxide.
の方法はの加水分解法に比較し原料が廉価で工業的
規模での生産が可能であるとの利点を有するものの水酸
化ジルコニウムに安定化剤が均質に分散していないため
か析出物である水酸化ジルコニウムを主体とするゲル
（以下単に水酸化ジルコニウムと称する）を乾燥、焼成
しても均質な組成及び結晶子を有する部分安定化酸化ジ
ルコニウム粉体が得られないという欠点を有する。Although the method of 1 has the advantage that the raw material is cheaper and can be produced on an industrial scale as compared with the hydrolysis method of 1, it is a precipitate because the stabilizer is not homogeneously dispersed in zirconium hydroxide. Even if a gel mainly containing zirconium hydroxide (hereinafter simply referred to as zirconium hydroxide) is dried and calcined, a partially stabilized zirconium oxide powder having a homogeneous composition and crystallites cannot be obtained.
かかる事情下に鑑み本発明者等は、中和共沈法における
上述の欠点を解決すべく鋭意検討した結果、イットリウ
ム、マグネシウム、セリウム、カルシウム等の金属塩を
酸化ジルコニウムに対し２．５〜４．０モル％となるよ
うに添加した水溶液のｐＨが約４〜５近傍に於いて水溶
液の粘度が急増し、溶液の全体撹拌が困難な状態を生起
し、ｐＨが約５を越えると再び溶液粘度が低下するとい
う現象が生じることを見出した。しかしてこの中和処理
時に於ける溶液の一時的粘度上昇が安定化剤としての水
酸化物のジルコニウムの水酸化物の粒子表面或いは粒子
近傍への均質な析出を妨げ、結果として均質な組成及び
結晶子を有する部分安定化酸化ジルコニウム粉末を得る
ことが出来ない原因であると推定し、中和処理時に於い
て粘度上昇が少なく、析出反応系の均一な撹拌が可能な
方法を見出すべく更に研究を重ねた結果、中和処理に際
し予め水溶液中に析出する水酸化ジルコニウムの核とな
るような種子水酸化ジルコニウムを添加存在せしめる場
合にはｐＨ４〜５の段階に於いても殆ど粘度上昇を招く
ことなく中和処理し得ることを見出し、本発明を完成す
るに至った。In view of such circumstances, the present inventors have conducted extensive studies to solve the above-mentioned drawbacks in the neutralization coprecipitation method, and as a result, metal salts of yttrium, magnesium, cerium, calcium, etc. were added to zirconium oxide in an amount of 2.5 to 4 When the pH of the aqueous solution added so as to be 0.0 mol% is about 4 to 5, the viscosity of the aqueous solution rapidly increases, and it becomes difficult to stir the solution as a whole. It has been found that a phenomenon that the viscosity is lowered occurs. However, the temporary increase in viscosity of the solution during the neutralization treatment hinders the uniform precipitation of zirconium hydroxide as a stabilizer on or near the particle surface of the hydroxide particles, resulting in a homogeneous composition and It is presumed that this is the reason why partially stabilized zirconium oxide powder having crystallites cannot be obtained, and further research is conducted to find a method capable of uniformly stirring the precipitation reaction system with a small increase in viscosity during the neutralization treatment. As a result, when seed zirconium hydroxide that becomes nuclei of zirconium hydroxide that is preliminarily precipitated in the aqueous solution during the neutralization treatment is added and present, the viscosity is almost increased even at the stage of pH 4 to 5. The inventors have found that the neutralization treatment can be performed without the need, and have completed the present invention.
すなわち本発明は、焼成後の組成が酸化物換算で酸化ジ
ルコニウムに対し酸化イットリウム、酸化マグネシウ
ム、酸化セリウムおよび酸化カルシウムの少なくとも１
種が２．５〜４．０モル％となる如く水溶性ジルコニウ
ム化合物とイットリウム、マグネシウム、セリウムおよ
びカルシウムの少なくとも１種の水溶性金属塩とを加
え、次いでアルカリ或いは炭酸アルカリを添加して析出
物を生成せしめ、得られた析出物を濾過、水洗し、乾
燥、焼成する酸化ジルコニウム粉体の製造方法に於い
て、アルカリ或いは炭酸アルカリの添加時に析出物に対
して１〜１０重量部の水酸化ジルコニウム（ジルコニウ
ムの炭酸塩は除く）を種子として添加することを特徴と
する酸化ジルコニウム粉体の製造方法を提供するにあ
る。That is, according to the present invention, the composition after firing is at least one of yttrium oxide, magnesium oxide, cerium oxide, and calcium oxide with respect to zirconium oxide in terms of oxide.
A water-soluble zirconium compound and at least one water-soluble metal salt of yttrium, magnesium, cerium, and calcium are added so that the amount of the seed becomes 2.5 to 4.0 mol%, and then alkali or alkali carbonate is added to deposit In the method for producing a zirconium oxide powder, the precipitate is filtered, washed with water, dried and calcined, and 1 to 10 parts by weight of hydroxide is added to the precipitate when alkali or alkali carbonate is added. It is another object of the present invention to provide a method for producing zirconium oxide powder, which comprises adding zirconium (excluding carbonate of zirconium) as seed.
以下本発明方法を更に詳細に説明する。The method of the present invention will be described in more detail below.
本発明の実施に際し使用される水溶性ジルコニウム化合
物としては、焼成後酸化ジルコニウムを形成するもので
あれば特にその種類は制限されないが、例えばオキシ塩
化ジルコニウム、硫酸ジルコニウムまたは塩基性炭酸ジ
ルコニウム或いはこれらの混合物等が挙げられる。The water-soluble zirconium compound used in the practice of the present invention is not particularly limited as long as it forms zirconium oxide after firing, and examples thereof include zirconium oxychloride, zirconium sulfate or basic zirconium carbonate or a mixture thereof. Etc.
他方、水溶性金属塩としては焼成後酸化イットリウム、
酸化マグネシウム、酸化セリウムおよび酸化カルシウム
を形成するものであればよく、イットリウム、マグネシ
ウム、セリウムおよびカルシウムの塩化物、硝酸塩、硫
酸塩または酢酸塩およびアルカリ金属塩、更にはこれら
の混合物が使用される。On the other hand, as the water-soluble metal salt, yttrium oxide after firing,
It is only necessary to form magnesium oxide, cerium oxide and calcium oxide, and yttrium, magnesium, cerium and calcium chlorides, nitrates, sulfates or acetates and alkali metal salts, and mixtures thereof are used.
水溶性ジルコニウム化合物に対する水溶性金属塩の添加
混合割合は焼成後の形態として酸化ジルコニウムに対し
酸化物換算で２．５〜４．０モル％の範囲で用いられ
る。酸化ジルコニウムに対する金属塩の添加混合割合が
上述の範囲を外れる場合には、この粉体を原料として得
られる焼結体の機械的強度が弱くなり適当ではない。The mixing ratio of the water-soluble metal salt to the water-soluble zirconium compound is in the range of 2.5 to 4.0 mol% in terms of oxide with respect to zirconium oxide as the form after firing. If the mixing ratio of the metal salt to zirconium oxide is out of the above range, the mechanical strength of the sintered body obtained from this powder becomes weak, which is not suitable.
所定量の水溶性ジルコニウム化合物に安定化剤としての
水溶性金属塩を加え、十分に撹拌混合した溶液には次い
で公知の方法に従い水酸化ナトリウム、水酸化カリウ
ム、水酸化アンモニウム等のアルカリ或いは炭酸ナトリ
ウム、炭酸水素ナトリウム、炭酸アンモニウム等の炭酸
アルカリ、および種子として析出が予定される水酸化ジ
ルコニウム重量の１〜１０重量％の水酸化ジルコニウム
を添加、撹拌して徐々に中和し、沈澱物を析出させる。A solution prepared by adding a water-soluble metal salt as a stabilizer to a predetermined amount of the water-soluble zirconium compound and thoroughly stirring and mixing the solution is then subjected to a known method such as an alkali such as sodium hydroxide, potassium hydroxide or ammonium hydroxide or sodium carbonate. Alkali carbonate such as sodium hydrogencarbonate and ammonium carbonate, and 1 to 10% by weight of zirconium hydroxide, which is expected to be deposited as seeds, are added and stirred to neutralize gradually to deposit a precipitate. Let
本発明方法の特徴はかかる中和処理時、種子として析出
量に対し１〜１０重量％の水酸化ジルコニウムを添加存
在せしめる所にあり、これにより理由は詳らかではない
が種子無添加の場合には中和析出過程において特定のｐ
Ｈ域で無数の微小な水酸化ジルコニウム結晶が発生し、
この結晶が急速に三次元の網目構造を形成、その内部に
水を取り込むことにより急激な粘度上昇を生起するので
あるが、種子が存在する場合には該種子により微小な結
晶の発生が抑制され、中和析出速度が調整され、異常な
粘度上昇が防止し得るものであると推測される。A feature of the method of the present invention is that 1 to 10% by weight of zirconium hydroxide is added to the seed as a seed during the neutralization treatment. The reason is not clear, but in the case of no seed addition, Specific p in the neutralization precipitation process
Countless minute zirconium hydroxide crystals are generated in the H region,
This crystal rapidly forms a three-dimensional network structure and causes a rapid increase in viscosity by incorporating water into the inside, but when seeds are present, the generation of minute crystals is suppressed by the seeds. It is presumed that the neutralization and precipitation rate can be adjusted to prevent an abnormal increase in viscosity.
種子として添加する水酸化ジルコニウムの組成は所望と
する製品と同一組成のものであれば特にその製法は制限
されないが、好ましくは種子として添加する溶液と同一
の組成液から中和法により析出せしめた水酸化ジルコニ
ウムを用いるのが良い。The composition of zirconium hydroxide added as seeds is not particularly limited as long as it has the same composition as the desired product, but preferably it was precipitated by a neutralization method from the same composition liquid as the solution added as seeds. It is better to use zirconium hydroxide.
本発明方法の実施に際し、種子としての水酸化ジルコニ
ウムは予想される中和共沈量に対し１〜１０重量％の範
囲内で添加存在せしめる。添加する種子量が１重量％未
満では粘度急増に対する抑制効果が小さく、また１０重
量％を越える場合には添加量に見返る効果はなく、むし
ろ経済上好ましくない。In carrying out the method of the present invention, zirconium hydroxide as seed is added and present within the range of 1 to 10% by weight based on the expected neutralization coprecipitation amount. If the amount of seeds added is less than 1% by weight, the effect of suppressing the rapid increase in viscosity is small, and if it exceeds 10% by weight, there is no effect on the added amount, which is rather economically undesirable.
中和処理時に於ける種子水酸化ジルコニウムの添加は中
和共沈せしめる液中に中和共沈開始前に分散させておく
方法、或いは中和用のアリカリ等の溶液中に予め分散さ
せておく方法等が挙げられるが、いずれの方法を適用し
てもよく、勿論これらの方法を組合せることも可能であ
る。The seed zirconium hydroxide is added during the neutralization process by dispersing it in the solution for neutralization coprecipitation before starting the neutralization coprecipitation, or by preliminarily dispersing it in a solution such as Alikari for neutralization. Examples of the method include any method, but any method may be applied and, of course, these methods may be combined.
かくして中和、沈澱析出させて得たジルコニウムの水酸
化物は公知方法により濾過し、溶液を分離した後水洗、
乾燥し、次いで６００〜１３００℃の温度で焼成され
る。The zirconium hydroxide thus obtained by neutralization and precipitation is filtered by a known method, and the solution is separated and washed with water,
It is dried and then calcined at a temperature of 600 to 1300 ° C.
焼成温度が６００℃よりも低いと水酸化ジルコニウムが
完全に酸化ジルコニウム粉末に変換できず、他方１３０
０℃を越える場合には酸化ジルコニウム粉体の粒子が粗
大化するので好ましくない。If the calcination temperature is lower than 600 ° C, zirconium hydroxide cannot be completely converted into zirconium oxide powder.
If the temperature exceeds 0 ° C, the particles of the zirconium oxide powder become coarse, which is not preferable.
以上詳述した本発明方法によれば、従来公知の中和共沈
法による水酸化ジルコニウムの析出生成時に該中和処理
に供する水溶液中に水酸化ジルコニウムを種子として添
加するという極めて簡単な方法により安定化剤が均質に
分散した水酸化ジルコニウムを得ることができ、このこ
とにより均質な組成および結晶子を有する部分安定化酸
化ジルコニウムの取得を可能ならしめたものであり、そ
の工業的価値は頗る大なるものである。According to the method of the present invention described in detail above, by a very simple method of adding zirconium hydroxide as seeds to an aqueous solution to be subjected to the neutralization treatment at the time of precipitation formation of zirconium hydroxide by a conventionally known neutralization coprecipitation method. It is possible to obtain zirconium hydroxide in which the stabilizer is homogeneously dispersed, which makes it possible to obtain partially stabilized zirconium oxide having a homogeneous composition and crystallites, and its industrial value is outstanding. It is great.
以下本発明方法を実施例により更に詳細に説明するが、
本発明はかかる実施例により制限されるものではない。Hereinafter, the method of the present invention will be described in more detail with reference to Examples.
The present invention is not limited to such examples.
実施例 ２０のポリエチレン製容器中でオキシ塩化ジルコニウ
ム５００ｇ（ＺｒＯ2換算で）および塩化イットリウム
５０ｇを純水１０に溶解した後、これに上述と同一組
成のオキシ塩化ジルコニウムおよび塩化イットリウムよ
りなる水溶液中より中和共沈法にて得た水酸化ジルコニ
ウム２５ｇを分散させた１０％アンモニア水（３）を
１０cc／min の速度で添加した。この中和共沈時の水溶
液の粘度変化を第１図に示す。更に比較のため中和用ア
ンモニア水に種子としての水酸化ジルコニウムを添加し
ない他は上記方法と全く同様に中和処理を行った。この
中和共沈時の水溶液の粘度変化も第１図に示す。In a polyethylene container of Example 20, 500 g of zirconium oxychloride (in terms of ZrO 2 ) and 50 g of yttrium chloride were dissolved in pure water 10 and then dissolved in an aqueous solution of zirconium oxychloride and yttrium chloride having the same composition as described above. 10% ammonia water (3) in which 25 g of zirconium hydroxide obtained by the neutralization coprecipitation method was dispersed was added at a rate of 10 cc / min. The change in viscosity of the aqueous solution during the neutralization coprecipitation is shown in FIG. Further, for comparison, the neutralization treatment was performed in exactly the same manner as above except that zirconium hydroxide as seed was not added to the neutralizing ammonia water. The change in viscosity of the aqueous solution at the time of this neutralization coprecipitation is also shown in FIG.
第１図より明らかな如く種子水酸化ジルコニウムを添加
存在せしめたアルカリ液で中和処理したものは種子を添
加分散させていないものに比較し、中和処理時の粘度上
昇が少ないことが分かる。As is apparent from FIG. 1, it is understood that the viscosity of the seeds neutralized with the alkaline solution containing zirconium hydroxide added does not increase the viscosity during the neutralization treatment as compared with the seeds not added and dispersed.
また上述の方法で析出した水酸化ジルコニウムを濾過、
水洗し、乾燥後１０００℃の温度で２時間焼成後振動ミ
ルで２時間粉砕処理した。このようにして得られた酸化
ジルコニウム粉末は種子添加品の場合平均粒径０．６
μ、＋２μ以上の粒子１０重量％であり、無添加品の平
均粒径は０．７μで、＋２μ以上の粒子は２０重量％で
あった。Further, the zirconium hydroxide deposited by the above method is filtered,
It was washed with water, dried, baked at a temperature of 1000 ° C. for 2 hours, and then pulverized with a vibration mill for 2 hours. The zirconium oxide powder thus obtained has an average particle size of 0.6 in the case of a seed-added product.
Particles of μ, +2 μ or more were 10% by weight, the average particle size of the additive-free product was 0.7 μ, and particles of +2 μ or more were 20% by weight.
このことより、本発明方法は安定化剤が均一にジルコニ
ア中、或いはその近傍に分散されているため粉体の組成
および結晶化が均質化され、粉体の局所的な凝集が少な
くなっているものと推察される。From this, in the method of the present invention, the stabilizer is uniformly dispersed in or near zirconia, so that the composition and crystallization of the powder are homogenized, and the local agglomeration of the powder is reduced. It is presumed to be a thing.
第１図は中和処理時に於いて安定化剤を分散させた水酸
化ジルコニウム析出反応系溶液の粘度変化を示すもので
あり、図中○は種子水酸化ジルコニウムを添加した場合
を、※は種子水酸化ジルコニウムを無添加の場合の例を
示す。Figure 1 shows the viscosity change of the zirconium hydroxide precipitation reaction system solution in which the stabilizer was dispersed during the neutralization treatment. In the figure, ○ indicates the case where seed zirconium hydroxide was added, and * indicates the seed. An example of the case where zirconium hydroxide is not added is shown.
Claims (2)
ウムに対し酸化イットリウム、酸化マグネシウム、酸化
セリウムおよび酸化カルシウムの少なくとも１種が２．
５〜４．０モル％となる如く水溶性ジルコニウム化合物
とイットリウム、マグネシウム、セリウムおよびカルシ
ウムの少なくとも１種の水溶性金属塩とを加え、次いで
アルカリ或いは炭酸アルカリを添加して析出物を生成せ
しめ、得られた析出物を濾過、水洗し、乾燥、焼成する
酸化ジルコニウム粉体の製造方法に於いて、アルカリ或
いは炭酸アルカリの添加時に析出物に対して１〜１０重
量部の水酸化ジルコニウム（ジルコニウムの炭酸塩は除
く）を種子として添加することを特徴とする酸化ジルコ
ニウム粉体の製造方法。1. The composition after firing is at least one of yttrium oxide, magnesium oxide, cerium oxide and calcium oxide with respect to zirconium oxide in terms of oxide.
A water-soluble zirconium compound and at least one water-soluble metal salt of yttrium, magnesium, cerium and calcium are added so as to be 5 to 4.0 mol%, and then alkali or alkali carbonate is added to form a precipitate, In the method for producing a zirconium oxide powder in which the obtained precipitate is filtered, washed with water, dried, and calcined, 1 to 10 parts by weight of zirconium hydroxide (zirconium oxide) is added to the precipitate when alkali or alkali carbonate is added. A method for producing a zirconium oxide powder, which comprises adding as a seed (excluding carbonate).
ニウムの炭酸塩は除く）が種子を添加する液と同一の組
成液から析出せしめた水酸化ジルコニウム（ジルコニウ
ムの炭酸塩は除く）である特許請求の範囲第１項記載の
方法。2. Zirconium hydroxide (excluding zirconium carbonate) as seed is zirconium hydroxide (excluding zirconium carbonate) precipitated from the same composition liquid as the liquid to which seeds are added. The method according to claim 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59205950A JPH0635329B2 (en) | 1984-10-01 | 1984-10-01 | Method for producing zirconium oxide powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59205950A JPH0635329B2 (en) | 1984-10-01 | 1984-10-01 | Method for producing zirconium oxide powder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6183627A JPS6183627A (en) | 1986-04-28 |
| JPH0635329B2 true JPH0635329B2 (en) | 1994-05-11 |
Family
ID=16515388
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP59205950A Expired - Lifetime JPH0635329B2 (en) | 1984-10-01 | 1984-10-01 | Method for producing zirconium oxide powder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0635329B2 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA1259080A (en) * | 1985-09-06 | 1989-09-05 | Nobuo Kimura | High density alumina zirconia ceramics and a process for production thereof |
| US4778671A (en) * | 1986-07-14 | 1988-10-18 | Corning Glass Works | Preparation of unagglomerated metal oxide particles with uniform particle size |
| FR2701471B1 (en) * | 1993-02-10 | 1995-05-24 | Rhone Poulenc Chimie | Process for the synthesis of compositions based on mixed oxides of zirconium and cerium, compositions thus obtained and uses of the latter. |
| FR2714370B1 (en) * | 1993-12-24 | 1996-03-08 | Rhone Poulenc Chimie | Precursor of a composition and composition based on a mixed oxide of cerium and zirconium, method of preparation and use. |
| CN115340126B (en) * | 2022-09-15 | 2024-04-12 | 包头稀土研究院 | Rare earth zirconate particles and preparation method thereof |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60215527A (en) * | 1984-04-06 | 1985-10-28 | Onoda Cement Co Ltd | Production of zirconium oxide fine powder |
-
1984
- 1984-10-01 JP JP59205950A patent/JPH0635329B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6183627A (en) | 1986-04-28 |
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