JPH0222184A - Production of porous inorganic oxide material - Google Patents

Abstract

PURPOSE:To obtain a porous inorganic oxide material having increased pore diameter and pore volume and excellent uniformity by adding fine particles of carbonaceous material to a solution containing a partial condensate of a silicon alkoxide, contacting the mixture with water and calcining the obtained gel. CONSTITUTION:Fine particles of a carbonaceous material are added to a solution containing a partial condensate of a silicon alkoxide or a solution containing a partial condensate of a silicon alkoxide and a compound of a metal selected from zirconium, titanium and aluminum. The obtained mixture is made to contact with water in the presence of a catalyst and the obtained gel is calcined at a high temperature in an oxidizing atmosphere. The silicon alkoxide is tetraethyl silicate, tetramethyl silicate, etc. The above metal compound is an alkoxide of Zr, Ti or Al or a compound produced by converting a part or total of the above alkoxide to chelate coordination or carboxyl group.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing an inorganic oxide porous body.

[Conventional technology]

Recently, a method for manufacturing inorganic porous bodies by the so-called sol-gel method using oxides containing organic substances such as alkoxides as raw materials has become known (Ceramic Industry Association Journal, g7 (g.
) P, g,? &(/97q)).

In addition to pure silica, the sol-gel method can easily form an oxide composition in which silica is uniformly mixed with other metal oxides on a molecular order. The sol-gel method has been widely studied as a method for producing glass that does not require melting and as a method for producing fine ceramic powder ("Science of Amorphous Glass", written by Masao Sakuhana, Rokaku Uchida).

On the other hand, after forming and drying raw materials containing refractory inorganic oxides such as silica and carbon black.

A method for producing a porous refractory inorganic oxide molded body is known (Japanese Patent Application Laid-open No. 31-1-QQIST), which is characterized by firing in an oxygen-containing air stream and simultaneously burning and removing carbon black.

The method for producing such a porous refractory inorganic oxide molded article uses, for example, during molding, precursors that will eventually become refractory inorganic oxides, such as water-conserving oxides such as aluminum and silicon, and alkoxides. It has been explained that it can be done.

[Problem to be solved by the invention]

However, in the above method for producing fine ceramic powder, the pore diameter of the resulting fine ceramic powder is small, and it is difficult to increase the pore diameter.

In addition, since the method for manufacturing the porous refractory inorganic oxide molded article involves secondary mixing in the solid powder state, it has to be said that the uniformity is still insufficient.

[Means to solve the problem]

That is, 1 the present invention provides carbonaceous fine particles to be added to a solution containing a partial condensate of silicon alkoxide or a solution containing a partial condensate of silicon alkoxide and a metal compound of zirconium, titanium or aluminum. Abstract: A method for producing an inorganic oxide porous body, which is characterized by contacting the resulting mixture with water in the presence of a catalyst to produce a gelled product, and then calcining the resulting gelled product in a high-temperature oxidizing atmosphere. That is.

Examples of the silicon alkoxide of the present invention include tetraethyl silicate and tetramethyl silicate.

As a partial condensate of silicon alkoxide.

Examples include those in which n in the following formula CI] is 0-10.

General formula [I] (In the formula, -n represents an integer of 0 to 70, and R represents an alkyl group.) The partial condensate of silicon alkoxide is produced by hydrolysis of silicon alkoxide.

The molar ratio of water to silicon alkoxide (H2O/Si(OR)4-R: alkyl group) when performing this hydrolysis reaction is 0. / -2.0 can be mentioned.

When performing this hydrolysis reaction, the silicon alkoxide can be dissolved well by adding a solvent such as methyl alcohol or ethyl alcohol.

The reaction temperature when performing this hydrolysis reaction is room temperature to
Temperatures of the order of go'c can be mentioned.

When carrying out this hydrolysis reaction, one reaction can be carried out smoothly by adding a catalyst, such as an acid, to the reaction system.

After the hydrolysis reaction, the solvent added to the reaction system or the alcohol produced can be removed by distillation to obtain the silicon alkoxide partial condensate of the present invention in a concentrated state.

Carbonaceous fine particles are added to the silicon alkoxide partial condensate obtained by the above hydrolysis reaction, thoroughly mixed, and then brought into contact with water in the presence of a catalyst to form a gelled product.

At this time, it becomes a partial condensate of silicon alkoxide.

Metal compounds of zirconium, titanium or aluminum may also be added.

Examples of metal compounds of zirconium, titanium, or aluminum include alkoxides, compounds in which part or all of the alkoxide is chelated, or compounds with carboxyl groups, such as compounds represented by the following structural formula.

M(OR)n + M(OR)n−x(OCOCH,)
x −M(OR)n−x(−0−(CH2) n−01
1M(OR) n (R'C0CHCoOR") x
-M(OR)n-x(R'C0CHCOR")x (g
-R, R' and R// are alkyl groups 1M 'd
Zr-Ti or Al, n represents a three-dimensional beam, and X represents an integer from θ to Hiro. ) Among these compounds, those which are easily mixed with silicon alkoxide are preferably used.

In the present invention, carbonaceous fine particles are added to a solution containing a silicon alkoxide partial condensate obtained in this manner, or a solution containing a silicon alkoxide partial condensate and a metal compound of zirconium, titanium, or aluminum. and the resulting mixture is brought into contact with water in the presence of a catalyst to perform a reaction to form a gelled product.

Carbon blank is used as carbonaceous fine particles.

Examples include crystalline cellulose and organic polymers. These carbonaceous fine particles are preferably those that can be made into particles of 7 μm or less when crushed. Also, these carbonaceous fine particles.

A solution containing a partial condensate of silicon alkoxide and a solution containing a partial condensate of silicon alkoxide and a metal compound of zirconium, titanium or aluminum (hereinafter, these solutions are collectively referred to as "partial condensate of silicon alkoxide"). It is preferable to use those that are insoluble or poorly soluble in the solution containing them. As these carbonaceous fine particles, what is generally called carbon black is preferably used.

Examples include Diablack A, Diablack H (Mitsubishi Setylene (manufactured by Denki Kagaku Kogyo ■), Ketchien Black EC (manufactured by Akzochemy), etc.).

It is preferable to add carbonaceous fine particles to a solution containing a partial condensate of silicon alkoxide, mix thoroughly, and explode a mixed solution as uniform as possible. When mixing, stirring may be performed at high speed using various devices generally called homogenizers. The amount of carbonaceous fine particles added is 1? when a solution containing a partial condensate of silicon alkoxide is converted into inorganic oxide. 0.0 for
! A range of about -2f can be mentioned. If this amount is small, it is difficult to exhibit the effect of adding carbonaceous fine particles.

If the amount is too high, the porosity of the obtained inorganic oxide porous body will be too high, and the mechanical strength of the porous body will decrease.

The carbonaceous fine particles thus obtained were added. The solution containing the partial condensate of silicon alkoxide is then brought into contact with water in the presence of a catalyst. Examples of the catalyst used include acid and ammonia.

Examples include organic bases and alkalis.

A preferred catalyst may include ammonia. This reaction is carried out by a method generally referred to as the so-called sol-gel method.

Added carbonaceous particles. Since a solution containing a partial condensate of silicon alkoxide exhibits lipophilic properties, one spherical particle was dispersed in water by adding the solution to water. This results in a so-called 0/W type state. In this case, it is preferable to add a general surfactant used to form an O/W type suspension state to the water.

Added carbonaceous particles. For 1 part of solution containing partial condensate of silicon alkoxide, aqueous solution/-7
00 parts (volume) are used.

The anti-Em degree for gelation is 5 to g.

C ranges may be mentioned. The reaction time is 0
．． A range of 5 to 211 h can be mentioned.

The carbonaceous fine particles obtained in this way were added. A gelled product of a partial condensate of silicon alkoxide and a mixture in which a metal compound of zirconium, titanium or aluminum is added to the partial condensate of silicon alkoxide (hereinafter simply referred to as a partial condensate of silicon alkoxide, etc.) is first prepared from water. Separation is performed by commonly used methods such as , decantation or filtration.

The obtained gelled product is washed if necessary and then kept at room temperature.
Dry at a temperature of about 20θ°C.

The dried product thus obtained is then calcined in a high temperature oxidizing atmosphere.

The firing temperature can range from SOO to 100°C.

The firing time can range from 1 hour to 7 days.

This firing may be performed multiple times, twice or more. For example, initially at a temperature of about SOO~700℃, l~2ψ
hours, and 700~ioo.

It may be baked at a temperature of °C for -24Z hours.

Firing is performed under a high temperature oxidizing atmosphere, for example under air circulation.

As described above, the inorganic oxide porous body of the present invention can be manufactured.

The inorganic oxide porous body produced by the present invention is as follows.

Used for separation agents, adsorbents, catalyst carriers, microorganism immobilization carriers, fillers, etc.

[Effect]

The inorganic oxide porous body obtained by the present invention is as follows.

By adding carbonaceous fine particles prior to the conversion from sol to gel in the manufacturing process, the partial condensate of silica alkoxide, etc. and the carbonaceous fine particles are mixed at a single molecule level, and this is then fired. It is thought that as a result of removing the carbonaceous fine particles as carbon dioxide gas, the portion where the carbonaceous fine particles were present gives uniform porosity to the inorganic oxide.

〔Example〕

Next, the present invention will be further explained with reference to examples, but the present invention is not limited to these examples.

In the examples, carbon black with a particle size of 70
0 Ku, DBP absorption amount (capacity of dibutyl phthalate absorbed by carbon black 1009-, unit ml/ /
00 y-1ASTMD, z<<1tI-79) / J smt/l o Of, specific surface area 20
A material having a physical property value of m''/% was used.

The pore distribution and amount were measured using a mercury intrusion porosimeter (Autopore qxoo manufactured by Micrometrics). The measurement range of pores is a radius of 20X or more.

The specific surface area was calculated by the BET method using the nitrogen adsorption method. The model used for the measurement was a Carlo Erba Numptofchik/
It's goo.

Example 1 and cotetraethyl orthosilicate (manufactured by Tokyo Kasei) s s
o %lC ethanol/-le b g, t s f, water A, j
'i- and 0. IN-HCl ethanol solution 9.3
! A solution consisting of f (HtO/S i (O
E t )4 mo/l/ratio (7,,7, HC1/30 minutes to prepare a partial condensate of tetraethyl orthosilicate. To this solution, dilute ester chelate (Al (Os-Bll)2 ( C6HQO3).

(manufactured by Alpha) 2s, o t; 1- and tetraethyl titanate (manufactured by Tokyo Kasei)/2. /? was added and mixed, first at 20°C under an argon atmosphere, then at is
The volatile liquid was distilled off by heating to 0°C.

1-Amyl alcohol 22. After adding S- and cyclohexane 7.5-, carbon black 6, Q? was added and treated for 3θ minutes using a biomixer (manufactured by Nippon Seiki Seiki Co., Ltd.) to obtain a solution in which the carbon blank was uniformly dispersed in the precursor solution.

Add this to 3J of water, 9f/-ethanol 13. Polygonum and Tween 20 (manufactured by Kanto Kagaku Co., Ltd., polyoxyethylene solpitan monolaure) 3. tt f
After forming a droplet by dropping it into an aqueous layer consisting of.

While continuing to stir, add 3 parts of 2g% ammonia water and 2 parts of water.
2.3 ml of ammonia solution was added little by little to form a gel. Stirring was continued for an additional 5 hours and then the resulting microspheres were precipitated overnight. After removing the supernatant by decantation.

Ethanol was added and stirred for 30 minutes, followed by decantation and washing again. After further separation from the solution by p-filtration, it was dried in a qo°C dryer for 5 hours. 2 of these dried products
After raising the temperature to 60θ°C at a rate of °C/m, it was held for 3 hours and fired under air circulation.

This was further baked at a temperature of 70θ°C for 5 hours.

The pore distribution measurement results are shown in FIG. 7, and the pore volume measurement results are shown in Table 1. The obtained fired product is /Q~so
They were micro spherical particles on the order of microns.

Example In Example 1, after baking at 1.00°C for 3 hours.

Except that I baked it in QOOC for another 5 hours.

The same procedure as in Example 1 was carried out. The results of measuring the pore distribution of the obtained porous body are shown in FIG. 1, and the results of measuring the pore volume are shown in Table 1.

Comparative Example 1 Synthesis was carried out in exactly the same manner as in Example 1, except that 4.0 g of carbon blank was not added. The obtained fired product mainly consisted of microspherical particles of about 5 to 30 microns, but compared to Example 1, there were many crushed products and the particle size was somewhat smaller. Table 1 shows the measurement results of the pore volume of the obtained porous body.

Comparative example Comparative Example / After baking at 11 t, oo°C for 3 hours.

Except that I baked it in QOOC for another 5 hours.

Pressure was carried out in the same manner as in Comparative Example 1. Table 1 shows the measurement results of the pore volume of the obtained porous body. Further, the measurement results of the pore distribution are shown in FIG. 11 together with Example 2.

Table 1 *) Pore radius 37. From the results of pore volumes of S scale to lo, oool, it is clearly recognized that the addition of carbon black increases the pore diameter and pore volume.

Example 3 Zirconium n-butoxide 25.5? .

Tetraethyl titanate / 2.57-aluminum diptoxide acetomesetate ester chelate 2! A precursor was prepared in the same manner as in Example 1 except that r and 9f were used. For this precursor da5-,
Example 1 except that carbon black 3.01 was added.
Microspheres were prepared in the same manner as above. The obtained fired product was mostly fine spherical particles of 5 o-bo microns. Pore radius 3q! The pore volume of rL~/Q, θool was 8qqmt/P.

Example Daka pump rack addition amount was 9.01 to the precursor Hiro 5.
The synthesis was carried out in the same manner as in Example 3, except for the following. Most of the obtained fired products were clean spherical particles of XO to 100 microns. Pore radius 37.5X~t
The pore volume of o, o o o X was 2.6/rnt/7, and a peak was observed at the pore radius '17/k.

Example S Using the precursor of Example 3, without adding t-amyl alcohol and cyclohexane, carbon black 6, O? was added and mixed for 30 minutes using a biomixer to obtain a solution in which carbon black was uniformly dispersed in the precursor. This was dispersed and gelled in the same manner as in Example 1 to produce microspheres.

Most of the obtained fired products were spherical particles of tio to 100 microns. The pore volume is 1.12 m1/2,
It showed a pore distribution with a peak at a pore diameter of about 22oK.

Comparative Example 3 Example S except that carbon black was not added
Microspheres were produced in the same manner. The obtained fired product is 2
They were spherical particles of 0 to 120 microns, and there were more crushed particles than in Example 5.

The pore volume was 0.73 m1 IP, and a peak in pore distribution existed at a pore diameter of 30 mm, with almost no pores having a pore diameter of xoo1 or more.

Example 6 Tetraethylorthosilicate) s +, J PK.

Ethanol 791g1. Mizugu, 71 and 0. lN-HC
Add a solution consisting of 2.0251' of ethanol solution.

A partial hydrolyzate of tetraethylorthosilicate was prepared by heating at 60° C. for 30 minutes. To this, zirconium n-butoxide 99. Q? .

Ethanol ioL? After adding and Impropatool/Qf- to make a homogeneous solution, after heating at 120°C/jgO°C
The volatile liquid was distilled off to obtain a precursor. This precursor 37.5-cyclohexane 9. Zrnt and carbon black! ? , 09- is added.

Mixed for 30 minutes.

Add this mixture to water! r3/9-. After dropping into an aqueous solution consisting of ethanol 601 and 'rween 209.01 to form droplets, stirring was continued.

2g% ammonia water q5- and water 10! tnll aqueous ammonia solution was added little by little to form a gel.

- After being left in the apparatus for the night, the precipitated microspheres were separated by decantation, ethanol was added, stirred, and allowed to stand again. The supernatant was separated by decantation and then dried using an evaporator. After further drying this sample at 230°C, the temperature was raised to 600°C/°C/min and fired for 3 hours. The physical properties of this sample are shown in Table 2.

Comparative Example A powder was produced in the same manner as in Example 6, except that Dacarbon black was not added. Table 2 shows the physical property values of the obtained fired product.

Example 7 Tetraethylorthosiliter) / , 77.09-.

3.021 μg of ethanol, 3.021 μg of water and 0.02 μg of ug-1 water. IN
- Ethanol solution of hydrochloric acid5. J! After adding a solution consisting of titanium tetraethoxide/!% and heating at 60°C for 30 minutes, titanium tetraethoxide/! ; 0. Of and ethanol io,.

? was added and stirred. This homogeneous solution was maintained at /20C and then heated at 130C to distill off the volatile liquid to obtain a precursor. Add 37 Jml of this precursor to 9.9 Jml of cyclohexane. After adding Hiroshi and carbon black S and OF and mixing for 30 minutes, water 5311, ethanol boft and Tween
It was added dropwise to an aqueous solution consisting of oq and og- and stirred. This was separated and dried in the same manner as in Example 1, and calcined at 600°C for 3 hours.

Table 2 shows the physical properties of the obtained powder.

From Comparative Example - A powder was produced in the same manner as in Example 7, except that Bonplak was not added.

The physical properties of the powder after firing at 600°C for 3 hours are shown in the second coat.

Table C Example g Tetraethyl orthosilicate 2! r09-, ethanol A I! :, 2 f, water 5. Da 1 and 0. IN-
A solution consisting of ethanol solution of hydrochloric acid/2-3 at 60℃
After heating for 0 minutes, zirconium n-butoxide II
7. OgL, ethanol lθ1, and isopropanol 10f were added, heated and maintained at 120°C, and then heated at iso°C to distill off the volatile liquid. This precursor 37. ! ; d4, 2 g of t-amyl alcohol, λ- and cyclohexane 9. Carbon black 2. ! ; 9
- was added and mixed. This was placed in an aqueous solution consisting of water s3/f, ethanol 601 and Tween 20 9-09- to form droplets, and then sg% ammonia water x
An aqueous solution prepared from is- and water os- was added little by little to form a gel. - After being left in the apparatus for the night, the precipitated microspheres were separated by decantation, ethanol was added, stirred, and allowed to stand again. The supernatant was separated by decantation and then dried using an enogu borator. This sample 2
After further drying at 3OC, heat up to 600℃/C/min.
It was baked for 3 hours. This sample was mostly microspherical particles of 5-50 microns.

Comparative Example 6 Synthesis was carried out in the same manner as in Example g except that carbon black was not added. The obtained particles had an irregular shape, although some spherical particles were observed.

〔Effect of the invention〕

According to the present invention, an inorganic oxide porous body with increased pore diameter and pore volume can be produced.

Furthermore, the porous body produced according to the present invention has a sharp pore distribution and is considered to have improved alkali resistance.

It is also expected to have the effect of reducing the number of hydroxyl groups on the surface of the porous body, which causes protein adsorption during protein separation.

[Brief explanation of the drawing]

FIGS. 1 and 2 are diagrams showing pore distribution curves of inorganic oxide porous bodies obtained in Examples 1 and 2 and Comparative Example.

Claims (1)

[Claims] (1) A mixture obtained by adding carbonaceous fine particles to a solution containing a partial condensate of silicon alkoxide or a solution containing a partial condensate of silicon alkoxide and a metal compound of zirconium, titanium, or aluminum. A method for producing an inorganic oxide porous body, comprising: contacting with water in the presence of a catalyst to produce a gelled product, and then calcining the obtained gelled product in a high-temperature oxidizing atmosphere.