JPH02221170A - Production of inorganic porous body - Google Patents

Abstract

PURPOSE:To obtain the porous body which has a large fine pore volume and the large gaps to act effectively and has a high property to absorb smells by drying a mixture composed of swellable inorg. laminar compds., org. pillars and solvent in a supercritical state, then calcining the mixture in such a manner that the org. pillars are carbonized. CONSTITUTION:For example, the swellable inorg. laminnar compds. are swollen and in succession, these compds., the org. pillars and the solvent are mixed. A stirring may be used at mixing and inorg. pillar is mixed if necessary. The org. pillars may be inserted between the layers of the above-mentioned laminar compds. at the time of mixing. The mixture subjected to the reaction in such a manner is cleaned and is then gelatinized by centrifugal sepn.; thereafter, the gels are oriented to a plate shape by a spatula, etc. The plate bodies are dried in the supercritical state above the critical point. The whole or part of the org. pillars are made to remain at this time. The plate bodies are thereafter calcined at the temp. around the decomposition temp. of the org. pillars to carbonize the org. pillars, by which the inorg. laminar compds. A contg. the residual carbon 52 existing between the layers of the inorg. laminar compds. are obtd.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a method for producing an inorganic porous body.

[Conventional technology]

Hitherto, inorganic porous bodies made by drying a swellable inorganic layered compound by hot air drying or freeze drying have been known (Japanese Patent Publication No. 6°2-20130, Japanese Patent Application Laid-Open No. 60-13781).
(See Publication No. 3). These inorganic porous bodies are dried using pillar materials inserted between the eyebrows of an inorganic layered compound as supports so as to maintain a gap between the eyebrows. These inorganic porous bodies can be used as functional materials such as heat insulating materials and adsorbents.

[Problem to be solved by the invention]

However, the above-mentioned inorganic porous material has a pore volume of 0.8
It is low at less than cc/g, the distance between the eyebrows is not wide enough to satisfy, and its insulation and adsorption properties are insufficient, making it difficult to call it a highly functional material.

In view of the above circumstances, this invention has an extremely large pore volume, large voids that work effectively, and the function of activated carbon (adsorption, especially the adsorption property for S-based (sulfur compound-based) odors). The object of the present invention is to provide a method for producing an inorganic porous material that also has the following properties:

[Means to solve the problem]

In order to solve the above problems, the method for producing an inorganic porous body according to the present invention is to dry a mixture of a swellable inorganic layered compound, an organic pillar, and a solvent in a supercritical state to the extent that the organic pillar remains. is fired so that the organic pillars are carbonized to obtain an inorganic porous body.

The inorganic porous body obtained by the production method according to the present invention is, for example, a petal-shaped or semi-shaped part of an inorganic layered compound,
Or, it is a card house-like or sponge-like aggregate, and the inorganic layered compound particles are not aggregated with the layers aligned in the same direction, but the inorganic layered compound particles are aggregated in various ways so that the layers are unevenly oriented. That's what I'm doing. For this reason, large voids are formed between the compounds, resulting in a highly porous body with a large pore volume. An inorganic porous body having such a structure can be made by drying a swellable inorganic layered compound in a swollen state in a supercritical state, but it may be made by other methods.

The inorganic porous body has at least 1100 to several thousand nanometers of inorganic layered compound between each other. More specifically, if it has a void distribution with a peak in the range of 100 nm to 1000 nm, for example, there will be a large number of voids, resulting in a porous body with an extremely large pore volume.Moreover, When there are many voids in this range, there are many types of particles that can be effectively adsorbed, making it versatile.

Furthermore, the inorganic layered compound is also present in the area between the eyebrows.
1 to several + nm, more specifically, for example, 60 to 20
If the pore distribution has a peak in the na+ range, the pore volume will increase due to the pores between the eyebrows, and
It becomes possible to adsorb small particles that cannot be captured in the spaces between compounds.

FIG. 1 (al is a schematic diagram showing an enlarged view of each inorganic layered compound A of the inorganic porous body obtained by the manufacturing method according to the invention described in claim 1. As shown in Figure +a), carbonized organic pillars (residual carbon) 52 exist between the layers 1 and 1. Due to the drying in a supercritical state, the layers 1 and the gaps 2 between them are sufficiently large.

FIG. 1 (bl is a schematic diagram showing an enlarged view of each inorganic layered compound B of the inorganic porous body obtained by the production method according to the invention set forth in claim 4. As shown in Figure fb), between layers 1 and 1, there are carbonized organic pillars 52 and inorganic pillars 4. Due to the drying in a supercritical state and the presence of the inorganic pillars 4, the gaps 2 between the layers 1 are sufficiently large.

On the other hand, in the case of conventional inorganic porous materials produced by hot air drying, the inorganic layered compounds overlap each other without any gaps, and there are almost no gaps between the particles, so the pore volume is much smaller. .

In addition, the inorganic layered compound A shown in FIG.
This is an organic pillar inserted between the eyebrows (intercalation). Inorganic layered compound B shown in Figure 1(b)
When mixing an inorganic layered compound, an organic pillar, an inorganic pillar, and a solvent, an organic pillar and an inorganic pillar are inserted between the eyebrows.

The method for producing an inorganic porous body according to the present invention is carried out, for example, as follows, but is not limited to the method described below. First, the swellable inorganic layered compound is swollen. Subsequently, the swollen swellable inorganic layered compound, organic pillars, and solvent are mixed. Stirring may be used for mixing. If necessary, inorganic and lar are also mixed. At the time of mixing, organic pillars or inorganic pillars may be inserted between the eyebrows of the swellable inorganic layered compound, if necessary. The fluid contained in the mixture is then removed by drying the mixture in a supercritical state. When drying in a supercritical state, it is necessary to carry out the drying under such conditions that all or part of the mixed organic pillars remain. Although it depends on the type of solvent, for example, the removal of the solvent can be completed after about 4 hours of supercritical drying, so this time and the time required for the contained organic pillars to be completely removed (varies depending on the type of organic pillars) Drying is carried out in a supercritical state by appropriately selecting the time between. Furthermore, the higher the supercritical drying pressure, the slightly shorter (extraction) time. If the supercritical drying time is shorter than the time required to remove the solvent, drying may not be possible, and if the time is longer than the time required to completely remove the organic pillars, no carbon may remain.

Note that the residual rate of carbonized organic pillars can be controlled by the amount of organic pillars added, the drying time of supercritical drying, the firing temperature and time, etc.

The solvent used for swelling the swellable inorganic layered compound is not particularly limited; for example, polar solvents such as water, ethanol, methanol, DMF (dimethylformamide), DMSO (dimethyl sulfoxide), and acetone can be used individually. , or two or more kinds are used in combination. Water is generally used as the solvent.

Examples of the swellable inorganic layered compound include Na-montmorillonite, Ca-montmorillonite, synthetic hectorite, and synthetic smectite (for example, 3-octahedral compounds. As 3-octahedral compounds, for example, , synthetic saponite, Na-hectolite, Li-hectolite, Na-teniolite, Li-teniolite), acid clay, and phyllosilicate minerals such as synthetic mica (here, either natural products or synthetic products may be used) These may be used alone or in combination, but it goes without saying that the invention is not limited to these. In addition, when using a poorly swellable inorganic layered compound such as Ca-montmorillonite and acid clay, it is necessary to apply strong shearing force by kneading or the like during swelling.

A substance such as a swellable clay mineral (which may be either a natural product or a synthetic product) is a combination of a large number of swellable inorganic layered compounds A1 shown on the left side of FIG. 2. Compound A, the main material
t is mixed with a solvent such as water, and further kneaded if necessary, and as shown on the right side of Figure 2, solvent 3 is impregnated between layers 1 and 1 to pre-swell it (.swelling). The distance between the eyebrows of an inorganic layered compound is, for example, about 150 in the case of clay minerals.

The organic pillar is not particularly limited, but for example, at least one selected from water-soluble polymer compounds, quaternary ammonium salts, higher fatty acids, amphoteric surfactants, and choline compounds is used.

The water-soluble polymer compound is not particularly limited, and examples include polyvinyl alcohol, polyethylene glycol (
(polyethylene oxide), methylcellulose, carboxymethylcellulose (CMC), polyacrylic acid, sodium polyacrylate, polyacrylamide, polyvinylpyrrolidone, etc., each alone or in combination
Used in combination with more than one species.

There are various possible quaternary ammonium salts and higher fatty acids, among which octadecyl group,
Those having groups such as hexadecyl group, tetradecyl group and dodecyl group are preferred. Such quaternary ammonium salts include octadecyltrimethylammonium salt, dioctadecyldimethylammonium salt, hexadecyltrimethylammonium salt, dioctadecyldimethylammonium salt, tetradecyltrimethylammonium salt, ditetradecyldimethylammonium salt, and the like. In addition, higher fatty acids include palmitic acid (hexadecyl acid), stearic acid (octadecyl acid), oleic acid (cis-9-octadecenoic acid), and linoleic acid (cis-9-octadecenoic acid).
s-9, cis-12-octadecadienoic acid), etc.
Each may be used alone or in combination of two or more.

Various choline compounds can be considered, but for example, (HOCHI CHI N (CHI)t)'0
H- (i.e., Cs HlsNO*), Cs H
l<C7! N01C% H14NOC4Hs Oa,
Cs I (4NoC= Hv Ot , Cs Hl−N
OCI HlIO- is preferred, and each is used alone or in combination of two or more.

There are various possible amphoteric surfactants, but
Among these, preferred are those in which the cation part is an aliphatic amine type and the anion part has at least one group selected from carboxyl group, sulfate ester group, sulfone group, and phosphate ester group. .

As the organic pillar used in this invention, other than those mentioned above can be used as long as it can be added to the swellable inorganic layered compound.

In the method for producing an inorganic porous body of the present invention, inorganic pillars are also mixed (preferably) before drying in a supercritical state.Since inorganic pillars are not removed by supercritical drying and subsequent calcination, the inorganic layer is The compound remains in the glabella and serves as a pillar that illuminates the glabellar space.

As the inorganic pillar, a colloidal inorganic compound, a hydrolyzate of alcoholate (hereinafter, the alcoholate for pillars will be referred to as "alcolate ■"), a cationic inorganic compound, etc. are used.

Colloidal inorganic compounds are not particularly limited, but include:
It is preferable to use a thermally stable oxide or one that expands when heated. Such compounds include, for example, 310g, SbtOs, FewOs
s , AIIt Os , Tl0z and Z r O □
These can be used alone or in combination. Although the particle size of such a colloidal inorganic compound is not particularly limited in this invention,
The particle size is preferably about 50 to 150 particles.

Considering functionality, the colloidal inorganic compound preferably has a function such as a catalytic function. Such compounds include Trot, Zr0z, A Nt Ox
, FesOx, etc., and these may be used alone or in combination. Since these colloidal inorganic compounds are positively charged, they form complexes with negatively charged inorganic layered compounds such as clay minerals, and adhere to the surface of the inorganic layered compounds and between the eyebrows. Then, by drying in a supercritical state, it becomes fine particles. When using silica sol as a colloidal inorganic compound, it is necessary to chemically modify the surface of the particles with a cationic inorganic compound or alcoholate, etc. Sometimes it is necessary to use something. However, in the case of the colloidal inorganic compounds exemplified above, for example,
It becomes possible to use commercially available sol as is, and it is also possible to obtain mass production effects.

As the alcoholate ■, for example, Si(OCg H
s)4, Si(OCHI)4, Ge(
OCg H? )4 , Qe (QCs Ha )4
, Ti (QC=H1)a, etc., but other materials may also be used.

Inorganic pillars usually remain in the form of metal oxides between the eyebrows.

In the present invention, the zero particle size (average particle size) of the inorganic pillars is also not particularly limited, but is, for example, a particle size of about 50 to 150 particles. The zero particle size of the inorganic pillar influences whether the inorganic pillar performs the intercalation reaction of the inorganic layered compound between the layers, but in this invention, the particle size is set to such a degree that the inorganic pillar does not cause the insertion reaction of the inorganic layered compound between the eyebrows. It may be.

As shown in FIGS. 3(a) and 4(a), the inorganic pillars 41 may be inserted as they are between the layers 1 and 1 of the swellable inorganic layered compound. Or the third
As shown in FIG. 4 (b) and FIG. And, after being modified with at least one of esters, it may be inserted between the layers 1 and 1. In these figures, 3 is a solvent and 51 is an organic pillar.

Cationic inorganic compounds used to modify the surface of inorganic pillars include titanium compounds, zirconium compounds, hafnium compounds, iron compounds, copper compounds, chromium compounds, nickel compounds, and zinc compounds. , aluminum compounds, manganese compounds, phosphorus compounds, boron compounds, etc. For example, T
i Cl a metal chloride, Zr0Cj2. metal oxychlorides, nitrate compounds, etc., but compounds other than these can also be used.

In addition, as alcoholate ■, Ti(OR), Zr
(OR)4, PO(OR)t, B(OR)8, etc. can be used, and specifically, for example, Ti (QC
s Hv ) a , Zr (QCs Hy ) a ,
PO(OCH3)4, PO(OCmHs)
4, B (OCHs) 4, B (OCm Hs)
4, etc., but other types can also be used. Note that these can be used alone or in combination.

For example, when using a hydrolyzate (or polymer) of Alcoholate I as an inorganic pillar, dissolve Alcoholate I in a solvent such as ethanol or isopropanol, and add water and a reaction catalyst such as hydrochloric acid to this solution. (hydrolysis catalyst)
Add and mix to cause a hydrolysis reaction. This hydrolysis reaction is preferably carried out at a temperature of about 70°C, although it is not particularly limited. Furthermore, when the hydrolysis reaction of the inorganic pillars has progressed to some extent and the nucleus 41 has grown (see Figure 3 (a)), alcoholate ■ and/or a cationic inorganic compound are added to the reaction solution. , if these compounds are subjected to an addition reaction on the surface of the layer 41, the result shown in FIG.
As shown in the figure, a reactant 42 whose surface is positively charged is obtained, and this reactant 42 is used as an inorganic pillar.

When using a colloidal inorganic compound as an inorganic pillar, as shown in Figure 3(a), an inorganic pillar 41 consisting of a nucleus that is not chemically modified may be used, or as shown in Figure 3 (bl) Add the alcoholate (2) and/or the cationic inorganic compound to the dispersion of the colloidal inorganic compound, and add these compounds to the surface of the core 41 made of the inorganic pillar material in the same way as in the previous case. The reactant 42 may be similarly obtained by reacting.

A mixed solution containing the above components is mixed with the swellable inorganic layered compound that has been swollen in advance.
Insertion (intercalation) between layers 1 and 1 of the inorganic layered compound. Although the temperature during mixing is not particularly limited in the present invention, it is preferably around 60 to 70°C.

Organic pillars and inorganic pillars mixed with a swellable inorganic layered compound are inserted between the glabella of all inorganic layered compounds, cases where they are not inserted between the glabella of all inorganic layered compounds, and cases where they are inserted between the glabella of all inorganic layered compounds. There may be a mixture of inserted items and non-inserted items. These differences are
This is caused by the gap between the eyebrows when the inorganic layered compound swells and the particle size of the organic pillars and inorganic pillars.

When water-soluble polymer compounds, quaternary ammonium salts, etc. are blended as organic pillars, as shown in Figure 4fa) or (bl), this organic pillar 51... is a layer of an inorganic layered compound. Push and hold between 1 and 1,
At the same time, the inorganic pillar 41... or 42...
It functions to slow down the movement of and keep it between layers 1 and 1. Retained inorganic pillar 41... or 4
2... thereby holds the space between Fjl and 1 expanded. Also, as shown in Figure 4(b),
When the inorganic pillar 42 is a reactant whose surface is modified, the positive charge on the surface electrically couples with the negative portion on the surface of the layer 1, thereby further expanding the gap between the layers 1 and 1. It is thought that it will be possible to keep it as it is.

After the reaction solution as described above is centrifuged to turn the sample into a gel state, it is oriented into a plate shape using a spatula or the like.

This plate-shaped body is dried in a supercritical state. Of course, drying may be started from the state in which the material is in the reaction solution.

Here, the supercritical state does not mean only when the critical point is exceeded (it also includes things that are just at the critical point. As a method for creating a supercritical state, for example, water contained between the eyebrows There is also a method of directly heating and pressurizing the solvent held and contained in the swellable layered compound to reach a state above its critical point, but in such a method, the critical point of water is 374. 2℃, critical pressure 217.6at+11
This is an extremely high value, requiring a larger drying container, which is highly dangerous. In order to avoid this, the water in the swellable layered compound should be replaced with ethanol, for example, and then carbon dioxide should be added to gradually replace the ethanol with carbon dioxide. A supercritical state may be brought about by heating and pressurizing a two-component system or a one-component system containing only carbon dioxide at a temperature and pressure above the critical point. In this case, it is also possible to send carbon dioxide above the critical point into the system for substitution.

Drying ends by allowing the fluid in a supercritical state to escape from the system. During this drying, all or part of the organic pillars are left as described above.

By such a method, the agglomeration and condensation during drying can be prevented, the structure before drying can be maintained as it is, and an inorganic porous material with extremely high porosity and a large pore volume can be obtained. An inorganic porous material dried by hot air drying or freeze drying has a significantly smaller pore volume than an inorganic porous material dried in a supercritical state. This is because the structure before drying cannot be well maintained.

The above description is about one embodiment of the present invention, and it goes without saying that the material may be manufactured by a method other than the method described above (a method other than drying in a supercritical state).

Note that the fluids that can be used as solvents are not limited to those mentioned above; fluids that can be made into critical fluids within a practical range are:
There are various examples, such as ethanol, methanol, carbon dioxide, dichlorodifluoromethane, and ethylene.

When drying in the supercritical state, conditions are selected so that only the fluid contained in the porous body is extracted and removed, and the organic pillars are left as much as possible.

After drying, firing is performed at a temperature around the decomposition temperature of the added organic pillars, for example, 200 to 350°C.

As a result, carbonized organic pillars, for example,
Carbon such as amorphous carbon remains between layers and/or between particles and exhibits the function of activated carbon. Further, by performing calcination after drying in a supercritical state, the inorganic porous body can be made to have stable characteristics.

For reference, critical conditions for major fluids are shown in Table 1.

Table 1 Since the inorganic porous material obtained by the production method according to the present invention has a large specific surface area, it can be used as having deodorizing action, adsorption action, catalytic action, etc. Furthermore, since the pore volume is large, it can also be used as a heat insulating material. However, the uses of the inorganic porous body are not limited to these.

[For production]

When a mixture of a swollen inorganic layered compound, an organic pillar, and a solvent is dried in a supercritical state, the drying is performed in a manner that maintains the aggregation state of the inorganic layered compound particles in the solvent. An aggregate with large voids between particles of the inorganic layered compound is obtained. By performing drying in a supercritical state, condensation of the solvent (fluid) between the layers of the inorganic layered compound is suppressed, and if a pillar material is inserted between the eyebrows, aggregation of the pillar material is also prevented. The area between the eyebrows does not shrink due to dryness, and wide voids are ensured between the layers of the inorganic layered compound. Therefore, it becomes a highly porous aggregate with a large pore volume, and an inorganic porous body with excellent adsorption and heat insulation properties can be obtained. Note that during drying in this supercritical state, it is necessary to prevent the organic pillars from being completely removed together with the fluid. The mixture is dried in a supercritical state and then fired so that the organic pillars are carbonized. Carbonized organic pillars contain amorphous carbon and have functions similar to activated carbon.

The organic pillar is at least one selected from the group consisting of a water-soluble polymer compound, a quaternary ammonium salt, a higher fatty acid, an amphoteric surfactant, and a choline compound,
It is convenient for producing inorganic porous bodies.

The swelling inorganic layered compound is Na-montmorillonite, C
a- At least one selected from the group consisting of montmorillonite, synthetic hectorite, synthetic smectite, acid clay, and synthetic mica, the porosity of the inorganic porous body,
It is convenient for functionality.

When an inorganic pillar is inserted between the eyebrows of a swellable inorganic layered compound, the inorganic pillar is dried in a supercritical state, and
Since it is not removed even during subsequent firing, when the inorganic layered compound remains between the eyebrows, it acts as a support and secures a wide space between the eyebrows. In this case, if the surface of the inorganic pillar is modified with a cationic inorganic compound or alcoholate, the pillar material is likely to be fixed between the eyebrows of the layered compound.

When the inorganic pillar is at least one selected from the group consisting of a colloidal inorganic compound, an alcoholate hydrolyzate, and a cationic inorganic compound, it is convenient for producing an inorganic porous body.

When the fluid contained in the swellable inorganic layered compound before drying is at least one selected from the group consisting of ethanol, methanol, carbon dioxide, and dichlorodifluoromethane, compared to when the fluid is water. Therefore, drying in a supercritical state can be easily performed. This is because these fluids have significantly lower critical pressures and critical temperatures than water. Of course, the water contained in the swellable inorganic layered compound in a swollen state is replaced with another fluid, such as ethanol, and this replaced fluid is further replaced with another fluid,
For example, even when drying is performed in a supercritical state using a two-component fluid without replacing it with carbon dioxide, the critical temperature and pressure conditions are gentler than with water, so drying is still easy.

〔Example〕

Specific examples and comparative examples of the present invention are shown below, but the present invention is not limited to the following.

Example 1 Alcoholate ■ S i (OCg Hs )
Ethanol (Hani Chemicals ■Special Reagent) was added to a (manufactured by Hansui Chemicals ■) and thoroughly mixed to form a solution. 2N hydrochloric acid was added to this solution, and it was heated to 70°C to perform a hydrolysis reaction, thereby producing a core for an inorganic pillar material.

Next, Ti, which is a cationic inorganic compound, is added to this solution.
A 4M aqueous solution of Cβ4 (manufactured by Hanui Chemical Co., Ltd.) was added, thoroughly mixed, and a reaction was carried out to obtain a reaction liquid (dispersion liquid of inorganic pillars) in which the reactants were dispersed.

In addition, Na-montmorillonite (Kunipia F manufactured by Kunimine Kogyo Co., Ltd.), which is a swelling layered compound, was dispersed in water and adjusted to a 0.8 wt% aqueous solution, and this was added to octadecyltrimethylammonium chloride (Japanese), which is a quaternary ammonium salt. The oil and fat nt!! cation AB) and the above inorganic pillar were reacted dropwise at the same time. The reaction was carried out at 60°C for 1
．． I went for 5 hours.

After the reaction, washing with ethanol and centrifugation were repeated several times, oriented into a plate shape with a spatula, and heated at 40°C and 80 atm without adding carbon dioxide (CO8), which has a relatively low critical point.
The mixture was dried for an hour and then fired in an electric furnace at 350°C for 2 hours to obtain an inorganic porous body.

The blending ratio of each component is a molar ratio, Si (OCI
HS) 4: Ethanol: 2N hydrochloric acid: T+C1,
=17':18:65:1.7, and Na-montmorillonite:octadecyltrimethylammonium chloride:SiO□=t:t:o,s.

Example 2 - Alcoholate I, Ti(OCl Ht)4
(Add 2N hydrochloric acid to Hanui Chemical ■! and hydrolyze it,
A peptizing reaction was performed to obtain an inorganic pillar material solution. However, T
i (QC, Ht)4: 2N hydrochloric acid = 1:12
．． 5 (weight ratio).

In addition, Na-montmorillonite, which is a swellable inorganic layered compound, is dispersed in water and adjusted to a 0.8 wL% aqueous solution, and octadecyltrimethylammonium chloride, which is a quaternary ammonium salt, and the above-mentioned inorganic pillar are simultaneously added dropwise to this. Made it react. The reaction was carried out at 60°C for 1.5 hours.

After the reaction, washing with ethanol and centrifugation were repeated several times, oriented into a plate shape with a spatula, and heated at 40°C and 80 atm without adding carbon dioxide (Co), which has a relatively low critical point.
The mixture was dried for an hour and then fired in an electric furnace at 350°C for 2 hours to obtain an inorganic porous body.

The blending ratio of each component was Na-montmorillonite dioctadecyltrimethylammonium chloride:T'tol=t:1:0.6 in terms of weight ratio.

Example 3 In Example 2, instead of the quaternary ammonium salt,
1 of polyvinyl alcohol (PVA: reagent manufactured by Hani Chemicals@, polymerization degree 500), which is one of the water-soluble polymer compounds.
An inorganic porous body was obtained in the same manner as in Example 2 except that a 0% aqueous solution was used.

Example 4 In Example 2, the same procedure as in Example 2 was used except that synthetic sabonite (Smecton SA, manufactured by Kunimine Industries Co., Ltd.), which is one of the synthetic smectites, was used instead of Na-montmorillonite. A porous body was obtained.

Example 5 In Example 2, titania-zirconia coated silica sol (colloidal inorganic compound) was used as the inorganic pillar.
An inorganic porous body was obtained in the same manner as in Example 2, except that Snowtex TZK (trade name) manufactured by Nissan Chemical Industries (trade name) was used.

Comparative Example 1 An inorganic porous body was obtained in the same manner as in Example 1, except that the drying was performed with hot air at 60°C.

Comparative Example 2 An inorganic porous body was obtained in the same manner as in Example 5, except that the drying was performed with hot air at 60°C.

Comparative Example 3 An inorganic porous body was obtained in the same manner as in Example 1, except that the firing was performed at 500° C. and no carbon remained.

Comparative Example 4 - An inorganic porous body was obtained in the same manner as in Comparative Example 1, except that the firing was performed at 500° C. and no carbon remained.

In Examples 1 to 5 and Comparative Examples 1 to 4, the presence or absence of residual carbon was determined visually. As a result, the inorganic porous bodies of Examples 1 to 5 and Comparative Example 12 were black in color and residual carbon was observed, and Comparative Example 3.
In No. 4, no residual carbon was observed.

For each inorganic porous material of Examples 1 to 5 and Comparative Examples 1 to 4, the specific surface area, pore volume, glabellar gap (glabellar distance), gap between compound particles (distance between compounds), and apparent density were The results are shown in Table 2. Note that Table 2 also shows the raw materials for the inorganic porous body, drying conditions, and firing conditions.

Furthermore, the deodorizing properties of each inorganic porous material were also investigated, and the results are shown in Table 3.

The specific surface area and pore volume are determined by BET in the nitrogen adsorption method.
I investigated using the method.

The glabellar space was obtained by obtaining an X-ray diffraction measurement graph.

Obtained by measurement.

The amount of compound voids showed the highest void value among the voids observed on the scanning electron micrograph of the surface of the porous material.

In order to measure the deodorizing properties, the following two deodorizing experiments were conducted using trimethylamine and methyl mercaptan as odor components, respectively.

Experiment ■ In a 300ml Erlenmeyer flask, add 0% inorganic porous material.
．． 3 g was added and the mouth of the Erlenmeyer flask was sealed with a stopper. Next, trimethylamine (9,4
8 vol.

As a result of the analysis, if the odor has been completely deodorized (gas chromatograph measurement value Oppm), repeat the above operation, and if the odor has not been completely deodorized, extend the time before sampling until it is completely deodorized. I checked the time.

Experiment ① 0.3 g of the inorganic porous material was placed in a 30 QmJ Erlenmeyer flask, and the mouth of the Erlenmeyer flask was sealed with a stopper. Next, methyl mercaptan (9
, 16% by volume) diluted 100 times, was injected, allowed to stand for 1 minute, irradiated with UV light, and then sampled 1ml of the gas in the Erlenmeyer flask and measured using a gas chromatograph. As a result of the analysis, when the odor was completely deodorized (gas chromatograph measurement value 0 ppn+), the UV irradiation time required for deodorization was recorded. In addition, when the odor is not completely deodorized, the UV irradiation time until the gas chromatograph measurement value settles to a substantially constant value and the gas chromatograph measurement result are shown.

The main equipment used for measurements etc. is as follows.

Nitrogen adsorption method: Trademark Autosoap 6, manufactured by Quantachrome Co., Ltd. As shown in Table 3, when comparing Example 1 and the corresponding Comparative Example 1, it is clear that the inorganic porous material manufactured by the method according to the present invention has a larger specific surface area, pore volume, and void size. It's there. Therefore, the inorganic porous material manufactured by the method according to the present invention exhibits excellent deodorizing properties (adsorption properties or catalytic functions). In addition, Example 1
Comparing with Comparative Example 3, it can be seen that the deodorizing effect is further enhanced by leaving carbonized organic pillars.

Note that the presence of carbon in an inorganic porous material generally limits the catalytic action, but in the case of this invention, T i O
As seen in the results of Examples 2 to 4 containing S catalyst, no such limitation was observed. Furthermore, the presence of carbon enhanced the deodorizing effect of methyl mercaptan, and it was considered that there was no problem.

〔Effect of the invention〕

Since the method for producing an inorganic porous body according to the present invention is as described above, the obtained inorganic porous body maintains its porosity well before drying, and has a large specific surface area and pore volume.
It has sufficiently large voids and contains carbon, which gives it excellent functionality.

Use of at least one selected from the group consisting of a water-soluble polymer compound, a quaternary ammonium salt, a higher fatty acid, an amphoteric surfactant, and a choline compound as the organic pillar is convenient for producing an inorganic porous body. be.

Use of at least one selected from the group consisting of Na-montmorillonite, Ca-montmorillonite, synthetic hectorite, synthetic smectite, synthetic mica, and acid clay as the swellable inorganic layered compound is convenient for producing inorganic porous bodies. It is.

When inorganic pillars are also used, the inorganic pillars remain between the eyebrows of the non-layered compound even after firing, ensuring voids, which is advantageous for the function of the inorganic porous body.

Use of at least one selected from the group consisting of a colloidal inorganic compound, an alcoholate hydrolyzate, and a cationic inorganic compound as the inorganic pillar is advantageous for producing an inorganic porous body.

When drying in a supercritical state, the swellable inorganic layered compound in a swollen state contains at least one fluid selected from the group consisting of ethanol, methanol, carbon dioxide, and dichlorodifluoromethane. Since it is possible to achieve a milder supercritical state than when water is contained, supercritical drying can be carried out under milder conditions.

[Brief explanation of the drawing]

FIG.
Figures (bl is an enlarged schematic diagram of a part of one example of an inorganic porous body obtained by the method according to the invention of claim 4, FIG. 2 is an enlarged schematic diagram showing the state of swelling of the swellable inorganic layered compound,
FIG. 3(a) is a schematic explanatory diagram showing a solution containing inorganic pillars and organic pillars whose surfaces are not modified; FIG. 3(b)
) is a schematic explanatory diagram showing a solution containing surface-modified inorganic pillars and organic pillars, and FIG.
FIG. 4(b) is a schematic explanatory diagram showing an inorganic layered compound to which inorganic pillars and organic pillars of FIG. 3(b) are added. It is. 1...N of the inorganic layered compound 2...Gap between layers 1 and 1 3...Solvent 4.41.42...Inorganic pillar 51...Organic pillar 52...Residual carbon A
B...Inorganic layered compound agent Patent attorney Takeshi Matsumoto Syllable 3 diagram (b) 4th

Claims (1)

[Claims] 1. A mixture of a swellable inorganic layered compound, an organic pillar, and a solvent is dried in a supercritical state to such an extent that the organic pillars remain, and then fired so that the organic pillars are carbonized. Manufacturing method of inorganic porous material. 2. The inorganic porous material according to claim 1, wherein the organic pillar is at least one selected from the group consisting of a water-soluble polymer compound, a quaternary ammonium salt, a higher fatty acid, an amphoteric surfactant, and a choline compound. Manufacturing method. 3. The inorganic compound according to claim 1 or 2, wherein the swellable inorganic layered compound is at least one selected from the group consisting of Na-montmorillonite, Ca-montmorillonite, synthetic hectorite, synthetic smectite, synthetic mica, and acid clay. Manufacturing method for porous bodies. 4. The method for producing an inorganic porous body according to any one of claims 1 to 3, wherein the mixture also contains inorganic pillars. 5. The method for producing an inorganic porous body according to claim 4, wherein the inorganic pillar is at least one selected from the group consisting of a colloidal inorganic compound, an alcoholate hydrolyzate, and a cationic inorganic compound. 6. Claims 1 to 5, wherein the swellable inorganic layered compound contains at least one fluid selected from the group consisting of ethanol, methanol, carbon dioxide, and dichlorodifluoromethane when drying is carried out in a supercritical state. A method for producing an inorganic porous body according to any one of the above.