JPH0656550A - Production of porous ceramics - Google Patents

Production of porous ceramics

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Publication number
JPH0656550A
JPH0656550A JP22649292A JP22649292A JPH0656550A JP H0656550 A JPH0656550 A JP H0656550A JP 22649292 A JP22649292 A JP 22649292A JP 22649292 A JP22649292 A JP 22649292A JP H0656550 A JPH0656550 A JP H0656550A
Authority
JP
Japan
Prior art keywords
mol
water
porous
metal alkoxide
surface area
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
Application number
JP22649292A
Other languages
Japanese (ja)
Inventor
Masahiro Watanabe
正広 渡邊
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Tosoh Corp
Original Assignee
Tosoh Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Tosoh Corp filed Critical Tosoh Corp
Priority to JP22649292A priority Critical patent/JPH0656550A/en
Publication of JPH0656550A publication Critical patent/JPH0656550A/en
Pending legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B38/00—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof
    • C04B38/0045—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof by a process involving the formation of a sol or a gel, e.g. sol-gel or precipitation processes
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/00474—Uses not provided for elsewhere in C04B2111/00
    • C04B2111/00793—Uses not provided for elsewhere in C04B2111/00 as filters or diaphragms
    • C04B2111/00801—Membranes; Diaphragms
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/00474—Uses not provided for elsewhere in C04B2111/00
    • C04B2111/0081—Uses not provided for elsewhere in C04B2111/00 as catalysts or catalyst carriers

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Dispersion Chemistry (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Compounds Of Heavy Metals (AREA)

Abstract

(57)【要約】 【構成】金属アルコキシドを金属アルコキシドに対して
０．１〜１００倍モルの水により加水分解を行い、得ら
れた水酸化物を溶媒中でｐＨを１〜５に調整することに
より分散させて得られるゾル溶液を乾燥し、３００〜１
１００℃にて焼成することからなる、多孔質セラミック
スの製造方法。 【効果】５０〜４００ｍ２／ｇの範囲で任意の比表面積
を選択することが可能であり、また、１０ｎｍ以下の細
孔を有している多孔質セラミックスを製造することが可
能である。(57) [Summary] [Structure] The metal alkoxide is hydrolyzed with 0.1 to 100 times mol of water with respect to the metal alkoxide, and the pH of the resulting hydroxide is adjusted to 1 to 5 in a solvent. Then, the sol solution obtained by dispersing is dried to 300 to 1
A method for producing a porous ceramic, which comprises firing at 100 ° C. [Effect] It is possible to select an arbitrary specific surface area within a range of 50 to 400 m 2 / g, and it is possible to produce a porous ceramic having pores of 10 nm or less.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は、無機分離膜、触媒担体
などとして有用な多孔質セラミックスの製造方法に関す
るものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a porous ceramic useful as an inorganic separation membrane, a catalyst carrier and the like.

【０００２】[0002]

【従来の技術】従来の多孔質セラミックスにおける多孔
質構造の制御方法としては、水酸化物にポリエチレング
リコール、メチルセルロース、ポリビニルアルコールな
どの水溶性のポリマーを加え、乾燥焼成を行う有機物添
加法や結晶種子となる水酸化物水溶液をアルカリ性側と
酸性側に交互に変化させ、水和物の溶解と成長とを制御
し均一な細孔と粒子を得るｐＨスイング法などがある。2. Description of the Related Art Conventional methods for controlling the porous structure of porous ceramics include adding a water-soluble polymer such as polyethylene glycol, methyl cellulose, or polyvinyl alcohol to hydroxide, followed by drying and firing an organic substance addition method or crystal seeds. There is a pH swing method in which the aqueous hydroxide solution is changed to the alkaline side and the acidic side alternately to control the dissolution and growth of the hydrate to obtain uniform pores and particles.

【０００３】[0003]

【発明が解決しようとする課題】しかし、上記の有機物
添加法では添加方法によっては細孔の分布が不均一化を
招き、また、細孔径の細かな制御には不向きである。ま
た、ｐＨスイング法においては、得られる細孔径が１０
ｎｍ以上であり、それ以下の細孔は得られていない。さ
らには、この手法は多孔質アルミナの製造方法にしか適
用できない。However, in the above-mentioned organic substance addition method, the distribution of pores becomes non-uniform depending on the addition method, and it is not suitable for fine control of the pore diameter. In the pH swing method, the obtained pore size is 10
The pores having a size of not less than nm and smaller than that are not obtained. Furthermore, this method can only be applied to the method for producing porous alumina.

【０００４】本発明は、これらの従来技術における問題
点を解決し、容易に５０〜４００ｍ２／ｇの広い範囲で
任意の比表面積を選択でき、かつ１０ｎｍ以下の平均細
孔径を有する多孔質セラミックスの製造方法の提供を目
的とするものである。The present invention solves these problems in the prior art, can easily select an arbitrary specific surface area in a wide range of 50 to 400 m 2 / g, and has a porous ceramic having an average pore diameter of 10 nm or less. The purpose of the present invention is to provide a manufacturing method of.

【０００５】[0005]

【課題を解決するための手段】本発明者は、多孔質セラ
ミックスの製造方法について種々の検討を行った結果、
加水分解を行う時の水の量および焼成温度を組み合わせ
ることにより、容易に５０〜４００ｍ２／ｇの広い範囲
で任意の比表面積を選択でき、かつ１０ｎｍ以下の平均
細孔径を有する多孔質セラミックスを得ることができる
ことを見出だし本発明を完成するに至った。Means for Solving the Problems As a result of various studies on the method for producing porous ceramics, the present inventors have found that
By combining the amount of water and the firing temperature during hydrolysis, it is possible to easily select an arbitrary specific surface area in a wide range of 50 to 400 m 2 / g and to obtain a porous ceramic having an average pore size of 10 nm or less. The inventors have found that they can be obtained and completed the present invention.

【０００６】すなわち、本発明は、金属アルコキシドを
金属アルコキシドに対して０．１〜１００倍モルの水に
より加水分解を行い、得られた水酸化物を溶媒中でｐＨ
を１〜５に調整することにより分散させて得られるゾル
溶液を乾燥し、３００〜１１００℃にて焼成することか
らなる多孔質セラミックスの製造方法を要旨とするもの
である。That is, according to the present invention, the metal alkoxide is hydrolyzed with 0.1 to 100 times mol of water with respect to the metal alkoxide, and the resulting hydroxide is adjusted to pH in a solvent.
Is adjusted to 1 to 5 to disperse and obtain a sol solution, which is dried and calcined at 300 to 1100 ° C.

【０００７】以下、本発明の詳細について説明する。The details of the present invention will be described below.

【０００８】本発明で用いられる金属アルコキシドは、
例えば、 Ａｌ（ＯＲ）３（但しＲは炭素数１〜５のアルキル基） Ｔｉ（ＯＲ）４（但しＲは炭素数１〜５のアルキル基） である。上記金属アルコキシドをアルコールに溶解さ
せ、アルコキシド溶液を調整するが、用いるアルコール
はアルコキシドとアルキル基を同じくすることが好まし
い。The metal alkoxide used in the present invention is
For example, it is Al (OR) 3 (provided that R is an alkyl group having 1 to 5 carbon atoms) Ti (OR) 4 (provided that R is an alkyl group having 1 to 5 carbon atoms). The metal alkoxide is dissolved in alcohol to prepare an alkoxide solution, and it is preferable that the alcohol used has the same alkoxide and alkyl group.

【０００９】上記アルコキシド溶液に水を添加し加水分
解を行い、得られた水酸化物を水あるいはアルコール中
に分散させゾル溶液を調整する。このとき添加する水の
量は、金属アルコキシドとのモル比で０．１≦Ｈ２Ｏモ
ル／金属アルコキシドモル≦１００であるが、アルキル
基に対し等モル以上にしてアルキル基を完全に除去する
のがよい。Ｈ２Ｏモル／金属アルコキシドモル＞１００
では得られる多孔質セラミックスに大きな違いは無い
が、乾燥時間が長くなるといった生産性の低下を招く。Water is added to the above alkoxide solution for hydrolysis, and the obtained hydroxide is dispersed in water or alcohol to prepare a sol solution. The amount of water added at this time is 0.1 ≦ H 2 O mole / metal alkoxide mole ≦ 100 in terms of molar ratio with the metal alkoxide, but the amount is at least equimolar to the alkyl group to completely remove the alkyl group. Is good. H 2 O mole / metal alkoxide mole> 100
Although there is no big difference in the obtained porous ceramics, it causes a decrease in productivity such as a longer drying time.

【００１０】添加の方法であるが水はアルコキシドを溶
液するのに用いたアルコールにて希釈して添加するのが
好ましい。この時の濃度は添加する水の量により異なる
が、希釈しすぎると乾燥工程での時間がかかるだけであ
り、希釈しないと加水分解に不均一が生じ、最終的な多
孔質セラミックスの細孔分布などの不均一化を招くの
で、ゾル溶液の濃度が酸化物換算で０．１〜１モル／ｌ
になるように希釈するのが好ましい。加水分解の方法と
しては、水あるいは上記水とアルコ−ルとの混合液の中
にアルコキシドを添加して行うのが好ましい。アルコキ
シド中に水あるいは混合液を添加すると、加水分解の不
均一化を招き、細孔分布などの不均一化を招き易い。Although it is a method of addition, it is preferable to add water after diluting water with the alcohol used for dissolving the alkoxide. The concentration at this time depends on the amount of water to be added, but if it is diluted too much, it will only take time in the drying process, and if it is not diluted, uneven hydrolysis will occur and the final pore distribution of the porous ceramics. As a result, the concentration of the sol solution is 0.1 to 1 mol / l in terms of oxide.
It is preferable to dilute so that The hydrolysis is preferably carried out by adding an alkoxide to water or a mixed solution of water and alcohol. When water or a mixed solution is added to the alkoxide, the hydrolysis becomes non-uniform, and the pore distribution is likely to be non-uniform.

【００１１】ついで、加水分解温度であるが、アルコキ
シド溶液および水あるいは前記混合液の両者とも同一の
温度にするのが好ましい。温度が低すぎるとアルコキシ
ドや水が凝固してしまうし、高すぎると水が沸騰してし
まうので０〜１００℃の範囲であれば問題ない。加水分
解温度は望む比表面積に応じて選択すれば良い。Regarding the hydrolysis temperature, it is preferable that both the alkoxide solution and water or the above-mentioned mixed solution have the same temperature. If the temperature is too low, the alkoxide and water will solidify, and if it is too high, the water will boil, so there is no problem within the range of 0 to 100 ° C. The hydrolysis temperature may be selected according to the desired specific surface area.

【００１２】上記の様にして得られたゾル溶液は水和物
の分散性を高めるために、ｐＨ１〜５に調整される。ｐ
Ｈが高すぎると水和物の凝集が起き、多孔質構造の不均
一化につながり、また、低すぎると得られる多孔質セラ
ミックスの変色をまねくこともある。ｐＨの値は使用し
た金属種により異なるが、水和物の等電点のｐＨより４
程度低いｐＨがもっとも望ましい。ｐＨ調整に使用する
酸は硝酸、硫酸、塩酸などの無機酸あるいは酢酸などの
有機酸が望ましいが、これらによる有意な差はない。The sol solution obtained as described above is adjusted to pH 1 to 5 in order to enhance the dispersibility of the hydrate. p
If H is too high, a hydrate aggregates, leading to non-uniformity of the porous structure, and if it is too low, it may cause discoloration of the resulting porous ceramics. The pH value will differ depending on the metal species used, but it will be 4 from the pH of the isoelectric point of the hydrate.
A low pH is most desirable. The acid used for pH adjustment is preferably an inorganic acid such as nitric acid, sulfuric acid, hydrochloric acid or an organic acid such as acetic acid, but there is no significant difference due to these.

【００１３】得られたゾル溶液は乾燥し、その後３００
〜１１００℃の温度により焼成を行う。焼成温度は選択
する金属種により異なるが、好ましくはＡｌでは４００
〜１０００℃、Ｔｉでは３００〜６００℃が良い。前記
範囲より低すぎると有機物やＯＨ基の残存があり、ま
た、高すぎては細孔の消失、比表面積の低下につなが
る。The sol solution obtained is dried and then 300
Baking is performed at a temperature of ˜1100 ° C. The firing temperature varies depending on the metal species selected, but is preferably 400 for Al.
˜1000 ° C., and for Ti, 300 to 600 ° C. is preferable. If it is lower than the above range, organic substances and OH groups may remain, and if it is too high, pores may disappear and the specific surface area may decrease.

【００１４】[0014]

【発明の効果】以上説明したように、本発明によれば、
５０〜４００ｍ２／ｇの範囲で任意の比表面積を選択す
ることが可能であり、また、１０ｎｍ以下の細孔を有し
ている多孔質セラミックスを製造することが可能であ
る。As described above, according to the present invention,
It is possible to select an arbitrary specific surface area within the range of 50 to 400 m 2 / g, and it is possible to produce a porous ceramic having pores of 10 nm or less.

【００１５】[0015]

【実施例】【Example】

実施例１ アルミニウムｓｅｃ−ブトキシド［Ａｌ｛０ＣＨ２ＣＨ
（ＣＨ３）２｝３］１３．３ｇと２−ブタノール１５ｍ
ｌを混合し、９０℃まで加熱した。加水分解の水あるい
は水ーアルコール混合液を９０℃に加熱し、上記アルコ
キシド溶液を添加して加水分解を行った。還流化にて３
時間攪拌した後、硝酸を０．３ｍｌ添加してｐＨを４．
１に調整してゾル溶液を調製した。ゾル溶液の濃度はア
ルミナ換算で０．２５ｍｏｌ／ｌである。得られたゾル
溶液を１００℃にて乾燥させたのち、６００〜１０００
℃にて焼成を行い、多孔質アルミナ膜を得た。ここで、
Ｈ２Ｏモル／Ａｌモルと比表面積の関係を図１に示し
た。また、Ｈ２Ｏモル／Ａｌモル＝１００の時の細孔分
布を図２に示した。Example 1 Aluminum sec-butoxide [Al {0CH 2 CH
(CH 3 ) 2 } 3 ] 13.3 g and 2-butanol 15 m
1 was mixed and heated to 90 ° C. Hydrolyzed water or a water-alcohol mixture was heated to 90 ° C., and the above alkoxide solution was added for hydrolysis. 3 at reflux
After stirring for an hour, 0.3 ml of nitric acid was added to adjust the pH to 4.
It was adjusted to 1 to prepare a sol solution. The concentration of the sol solution is 0.25 mol / l in terms of alumina. The obtained sol solution is dried at 100 ° C. and then 600-1000.
Firing was carried out at 0 ° C to obtain a porous alumina film. here,
The relationship between the H 2 O mole / Al mole and the specific surface area is shown in FIG. The pore distribution when H 2 O mol / Al mol = 100 is shown in FIG.

【００１６】実施例２ チタニウムイソプロポキシド［Ｔｉ｛ＯＣＨ（ＣＨ３）
２｝４］１５．０ｇをイソプロピルアルコ−ル中に混合
して、実施例１と同様にして、加水分解を行いゾル溶液
を調製した（この時のゾル溶液のｐＨは１．５であっ
た）。得られたゾル溶液を５０℃にて乾燥させ、４００
℃で焼成を行い、多孔質チタニア膜を得た。ここで、Ｈ
２Ｏモル／Ｔｉモルと比表面積の関係を図３に示した。
Ｈ２Ｏモル／Ｔｉモル＝１００の時の細孔分布を図４に
示した。Example 2 Titanium isopropoxide [Ti {OCH (CH 3 )]
2 } 4 ] 15.0 g was mixed in isopropyl alcohol and hydrolyzed in the same manner as in Example 1 to prepare a sol solution (the pH of the sol solution at this time was 1.5). ). The sol solution obtained is dried at 50 ° C. to give 400
Firing was performed at ° C to obtain a porous titania film. Where H
The relationship between 2 O mol / Ti mol and the specific surface area is shown in FIG.
The pore distribution when H 2 O mol / Ti mol = 100 is shown in FIG.

【００１７】実施例３ チタニウムイソプロポキシド１５．０ｇをイソプロピル
アルコ−ル中に混合して、各温度においてＨ２Ｏモル／
Ｔｉモル＝２００にて加水分解を行った。得られたゾル
溶液より実施例２と同様にして多孔質チタニア膜を得
た。この時の加水分解温度と比表面積の関係を図５に示
した。Example 3 15.0 g of titanium isopropoxide was mixed in isopropyl alcohol, and H 2 O mol / mol was added at each temperature.
Hydrolysis was performed at Ti mol = 200. A porous titania film was obtained from the obtained sol solution in the same manner as in Example 2. The relationship between the hydrolysis temperature and the specific surface area at this time is shown in FIG.

【図面の簡単な説明】[Brief description of drawings]

【図１】実施例１におけるＨ２Ｏモル／Ａｌモルと多孔
質アルミナの比表面積との関係を示す図である。FIG. 1 is a diagram showing a relationship between H 2 O mol / Al mol and a specific surface area of porous alumina in Example 1.

【図２】実施例１で得られた多孔質アルミナの、Ｈ２Ｏ
モル／Ａｌモル１００のときの細孔分布を示す図であ
る。FIG. 2 H 2 O of the porous alumina obtained in Example 1
It is a figure which shows a pore distribution at the time of mol / Al mol 100.

【図３】実施例２におけるＨ２Ｏモル／Ｔｉモルと多孔
質チタニアの比表面積との関係を示す図である。FIG. 3 is a diagram showing a relationship between H 2 O mol / Ti mol and a specific surface area of porous titania in Example 2.

【図４】実施例２で得られた多孔質チタニアの、Ｈ２Ｏ
モル／Ｔｉモル１００のときの細孔分布を示す図であ
る。FIG. 4 H 2 O of the porous titania obtained in Example 2
It is a figure which shows a pore distribution at the time of mol / Timol100.

【図５】実施例３における加水分解温度と多孔質チタニ
アの比表面積との関係を示す図である。5 is a diagram showing the relationship between the hydrolysis temperature and the specific surface area of porous titania in Example 3. FIG.

Claims (1)

【特許請求の範囲】[Claims] 【請求項１】金属アルコキシドを金属アルコキシドに対
して０．１〜１００倍モルの水により加水分解を行い、
得られた水酸化物を溶媒中でｐＨを１〜５に調整するこ
とにより分散させて得られるゾル溶液を乾燥し、３００
〜１１００℃にて焼成することを特徴とする、多孔質セ
ラミックスの製造方法。1. A metal alkoxide is hydrolyzed with 0.1 to 100 moles of water relative to the metal alkoxide,
The sol solution obtained by dispersing the obtained hydroxide in a solvent by adjusting the pH to 1 to 5 is dried,
A method for producing porous ceramics, which comprises firing at ˜1100 ° C.
JP22649292A 1992-08-04 1992-08-04 Production of porous ceramics Pending JPH0656550A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP22649292A JPH0656550A (en) 1992-08-04 1992-08-04 Production of porous ceramics

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP22649292A JPH0656550A (en) 1992-08-04 1992-08-04 Production of porous ceramics

Publications (1)

Publication Number Publication Date
JPH0656550A true JPH0656550A (en) 1994-03-01

Family

ID=16845956

Family Applications (1)

Application Number Title Priority Date Filing Date
JP22649292A Pending JPH0656550A (en) 1992-08-04 1992-08-04 Production of porous ceramics

Country Status (1)

Country Link
JP (1) JPH0656550A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003301167A (en) * 2002-02-07 2003-10-21 Nihon University Method for producing sol and method for treating substrate for water repellency
US7066041B2 (en) * 2000-10-03 2006-06-27 Linak A/S Linear actuator
JP2008174419A (en) * 2007-01-19 2008-07-31 Shinshu Univ Titania microporous membrane and method for producing the same

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7066041B2 (en) * 2000-10-03 2006-06-27 Linak A/S Linear actuator
JP2003301167A (en) * 2002-02-07 2003-10-21 Nihon University Method for producing sol and method for treating substrate for water repellency
JP2008174419A (en) * 2007-01-19 2008-07-31 Shinshu Univ Titania microporous membrane and method for producing the same

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