JPH0571546B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] This invention relates to an inorganic porous body made of an inorganic layered compound. [Prior Art] Conventionally, inorganic porous bodies made by drying (hot air) a swollen inorganic layered compound have been known. Drying is performed using pillar materials inserted between the layers of the inorganic layered compound as supports to maintain voids between the layers. This inorganic porous material can be used as a functional material such as a heat insulating material or an adsorbent (Japanese Patent Publication No. 101310/1983,
(See Publication No. 13781). [Problem to be Solved by the Invention] However, the above-mentioned inorganic porous material has a low pore volume of 0.8 cc/g or less, an insufficiently wide interlayer spacing, and insufficient heat insulation and adsorption properties. It is hard to call it a highly functional material. Activated carbon, which has long been known as a porous material, has very small pores of several angstroms, so it cannot be called a highly functional material. In view of the above circumstances, it is an object of the present invention to provide an inorganic porous body made of an inorganic layered compound having an extremely large pore volume and large voids that act effectively. [Means for Solving the Problems] In order to solve the above problems, the present invention is configured as follows. The inorganic porous body according to the invention according to claims 1 to 5 is a porous body obtained by drying a swellable inorganic layered compound in a swollen state in a supercritical state. In the inorganic porous body according to claim 2, the inorganic pillar material whose surface is modified with at least one selected from a cationic inorganic compound and an alcoholate is inserted between the layers of the swellable inorganic layered compound. It is dried. In the inorganic porous body according to claim 3, the swellable inorganic layered compound is dried with an organic pillar material inserted between the layers, and at the same time, the pillar material is removed from between the layers during the drying. It is something that In the inorganic porous body according to claim 4, the fluid contained in the swellable inorganic layered compound in a swollen state is
Ethanol, methanol, carbon dioxide, and
At least one selected from dichlorodifluoromethane. The inorganic porous material according to claim 5 is dried by replacing the water contained in the swellable inorganic layered compound in a swollen state with ethanol, and then replacing the ethanol with carbon dioxide. The inorganic porous material according to claim 6 is a card house-like or sponge-like aggregate of inorganic layered compounds in the shape of flower petals or cicada wings. The inorganic porous body according to claim 7 is a porous body in which inorganic layered compounds are gathered together so as to have a void distribution with a peak in the range of at least 100 nm to several thousand nm. In the inorganic porous body according to claim 8, the inorganic layered compound has a void distribution with a peak in the range of several nanometers to several tens of nanometers even between the layers. The inorganic porous body according to claim 9 further includes an inorganic layered compound with pillars inserted between the layers. [Operation] When the inorganic layered compound in a swollen state is dried in a supercritical state, the layered compound particles are dried in a manner that maintains the aggregation state in the solvent, and the particles of the inorganic layered compound are dried. An aggregate with large voids 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 pillar materials are inserted between the layers, aggregation of the pillar materials is also prevented. The space between the layers does not shrink as it dries, and wide voids are ensured between the layers of the inorganic layered compound. Therefore, it becomes an aggregate with high porosity and large pore volume, resulting in an inorganic porous body with excellent adsorption and heat insulation properties. When drying is performed without inserting a pillar material between the layers of the swellable inorganic layered compound, the gap between the layers that once opened due to swelling becomes narrower than when the pillar material is present, but drying is carried out in a supercritical state. If this is done, the inorganic layered compound will form an aggregate like a house of cards or a sponge, so even if the voids between the layers within the compound are not sufficient, there will be large voids between the compounds and the pore volume will be sufficient. It becomes a porous body. When the inorganic pillar material is inserted between the layers of the swellable inorganic layered compound, the inorganic pillar material serves as a support and a wide interlayer gap is secured. In this case, if the surface of the inorganic pillar material is modified with a cationic inorganic compound or alcoholate, the pillar material is likely to be fixed between the layers of the layered compound. Organic pillar materials also act as supports between layers. However, depending on the usage conditions, residual organic pillar material (especially carbon) may become a problem. The organic pillar material can be removed by firing the inorganic porous material so that it remains between the layers, but the number of steps increases and, moreover, carbon inevitably remains. In this respect, since the organic pillar material is extracted by the fluid in a supercritical state, it can be removed from between the layers together with the fluid during drying. Drying in a supercritical state is very convenient because the above-mentioned firing step is not required and residual carbon can be suppressed. When the fluid containing the swellable inorganic layered compound in a swollen state is ethanol, methanol, carbon dioxide, and dichlorodifluorometa,
Compared to water, 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, even if the water contained in the swellable inorganic layered compound in a swollen state is replaced with ethanol and carbon dioxide as a two-component fluid and dried in a supercritical state, the critical temperature is lower than that of water. Since the pressure conditions are gentle, drying is also easy. When an inorganic porous material has petal-like or cicada-like inorganic layered compounds gathered together to form a card house-like or sponge-like aggregate, there are large voids between the compounds. , it is 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. Inorganic layered compounds with at least 100n between each other
If the porous material has a void distribution with a peak in the range of m to several thousand nanometers, there will be many large voids, resulting in a porous body with an extremely large pore volume. Moreover, when there are many voids in this range, a large number of types of particles can be effectively adsorbed, thereby providing versatility. Furthermore, there are several n layers of inorganic layered compounds between the layers.
If the pore distribution has a peak in the range of m to several tens of nanometers, the pore volume will increase due to the presence of voids between the layers.
Moreover, it becomes possible to adsorb even small particles that cannot be captured in the spaces between compounds. When pillars are inserted between the layers of the inorganic layered compound, the gaps between the layers of the inorganic layered compound are wide due to the supporting action of the pillars. [Example] The present invention will be described in detail below with reference to the drawings showing one example thereof. FIG. 1 is a scanning electron micrograph (magnification: 20,000 times) showing the particle structure of the inorganic layered compound by enlarging the surface of the inorganic porous material according to the invention as claimed in claim 1. This inorganic porous material is a porous material obtained by drying a swellable inorganic layered compound in a swollen state in a supercritical state. As shown in FIG. 1, the inorganic porous material is a card house-like or sponge-like aggregate of petal-like or cicada-like inorganic layered compounds. In this inorganic porous body, the inorganic layered compound has a distance of at least 100 nm to several thousand nanometers between each other.
m, more specifically, for example, has a void distribution with a peak in the range of 100 nm to 1000 nm,
The inorganic layered compound has a thickness of several nanometers to several tens of nanometers between the layers.
m, more specifically, has a void distribution with a peak in the range of, for example, 6 nm to 20 nm. As shown in FIG. 2, in each inorganic layered compound A, an inorganic pillar 4 is inserted between the layers 1, 1, so that the gap 2 between the layers 1, 1 is made sufficiently large. In the conventional inorganic porous material produced by hot air drying, as shown in FIG. 8, the inorganic layered compounds overlap each other without any gaps, and there are almost no gaps between the particles. Therefore, the pore volume is much smaller. Next, the process of manufacturing this inorganic porous body will be explained. First, the swellable layered compound is swollen. Swellable layered compounds include Na-montmorillonite, Ca
- montmorillonite, 3-octahedral synthetic smectite (e.g. synthetic saponite, Na-hectolite, Li-hectolite, Na-teniolite, Li
- teniolite, etc.), acid clay, synthetic mica, etc., but needless to say, they are not limited to the above-mentioned examples. In addition, when using a hardly swelling layered compound such as Ca-montmorillonite or 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 is a combination of a large number of swellable inorganic layered compounds A ₁ shown on the left side of FIG. This compound A ₁ , which is the main material, is mixed with a solvent such as water, and further kneaded if necessary, and as shown on the right side of Figure 3, solvent 3 is impregnated between layers 1 and 1 to swell it in advance. I'll let it happen. Water is generally used as the solvent 3, but other polar solvents such as methanol, ethanol, DMF,
DMSO, acetone, etc. may be used alone or in combination. Subsequently, a pillar material is inserted into the swollen swellable inorganic layered compound. As the inorganic pillar inserted between the layers of the swellable layered compound, a colloidal inorganic compound and a hydrolyzate of alcoholate (hereinafter, the alcoholate for pillars will be referred to as "alcolate I") are used. The colloidal inorganic compound is not particularly limited, but it is preferable to use a thermally stable oxide or one that expands when heated. Examples of such compounds include SiO ₂ ,
Examples include Sb ₂ O ₃ , Fe ₂ O ₃ , Al ₂ O ₃ , TiO ₂ , and ZrO ₂ , and these may be used alone or in combination. Although the particle size of such a colloidal inorganic compound is not particularly limited in the present invention, it is preferably about 50 to 150 Å. As alcoholate I, for example, Si
(OC ₂ H ₅ ) ₄ , Si (OCH ₂ ) ₄ , Ge (OC ₃ H ₇ ) ₄ , Ge
(OC ₂ H ₅ ) ₄ , Ti(OC ₃ H ₇ ) ₄ , etc. can be used, but materials other than these can also be used. The inorganic pillar material usually remains in the form of metal oxide between the layers. The above-mentioned inorganic pillars may be inserted between the layers of the swellable layered compound as they are, but if the surface thereof is a cationic inorganic compound and an alcoholate other than the alcoholate I (hereinafter referred to as "alcolate"). , and ester, and then inserted between the layers. Cationic inorganic compounds used to modify the surface of inorganic pillar materials include titanium compounds, zirconium compounds, hafnium compounds, iron compounds, copper compounds, chromium compounds,
Examples include nickel-based compounds, zinc-based compounds, aluminum-based compounds, manganese-based compounds, phosphorus-based compounds, boron-based compounds, etc., such as metal chlorides of TiCl ₄ or metal oxychlorides such as ZrOCl ₂ , or There are nitrate compounds, etc., but compounds other than these can also be used. In addition, alcoholates include Ti(OR) ₄ ,
Zr(OR) ₄ , PO(OR) ₃ , B(OR) ₃ , etc. can be used, and specifically, for example, Ti(OC ₃ H ₇ ) ₄ , Zr
(OC ₃ H ₇ ) ₄ , PO (OCH ₂ ) ₄ , PO (OC ₂ H ₅ ) ₄ , B
(OCH ₃ ) ₄ , B(OC ₂ H ₅ ) _4, etc., but other materials may also be used. Note that these can be used alone or in combination. In addition, in this invention, an organic pillar material consisting of at least one selected from a water-soluble polymer compound, a quaternary ammonium salt, a higher fatty acid, an amphoteric surfactant, and a choline compound can be used alone or in an inorganic manner. It can also be inserted between the layers 1 and 1 of the swellable inorganic layered compound together with the pillar material. Various water-soluble polymer compounds can be considered, such as polyvinyl alcohol, polyethylene glycol, polyethylene oxide, methylcellulose, carboxymethylcellulose, polyacrylic acid, sodium polyacrylate,
Examples include polyacrylamide, polyvinylpyrrolidone, and the like. Furthermore, various types of quaternary ammonium salts and higher fatty acids can be considered, but among them, those having groups such as octadecyl group, hexadecyl group, tetradecyl group, and dodecyl group are preferable. Such quaternary ammonium salts include octadecyltrimethylammonium salt,
Dioctadecyldimethylammonium salt, hexadecyltrimethylammonium salt, dihexadecyldimethylammonium salt, tetradecyltrimethylammonium salt, ditetradecyldimethylammonium salt, etc., and higher fatty acids include:
These include palmitic acid, stearic acid, oleic acid, and linoleic acid. Various choline compounds are possible, but
For example, [HOCH ₂ CH ₂ N(CH ₃ ) ₃ ] ⁺ OH ^- ,
_{C5H14ClNO , C5H14NOC4H5O6 , _ _ _}
Preferred examples include C ₅ H ₁₄ NOC ₆ H ₇ O ₇ and C ₅ H ₁₄ NOC ₆ H ₁₂ O ₇ . In addition, various types of amphoteric surfactants can be considered, but among them, the cation part is an aliphatic amine type, and the anion part is a carboxyl group, a sulfate ester group, a sulfone group, or a phosphoric acid ester group. Those having at least one group selected from ester groups are preferred. As the organic pillar material, materials other than those mentioned above may be used in the present invention as long as they can be inserted between the layers of the swellable inorganic layered compound. Next, insertion between layers will be specifically explained. For example, when using a polymer of Alcoholate I as the inorganic pillar material, Alcoholate I
A solvent such as ethanol or isopropanol is added and dissolved, and a reaction catalyst (hydrolysis catalyst) such as water and hydrochloric acid is added and mixed to cause a hydrolysis reaction.
This hydrolysis reaction is carried out at, but not limited to, 70°C.
It is preferable to carry out the process at a temperature of about 100%. In addition, at the stage where the hydrolysis reaction of such an inorganic pillar material has progressed to a certain extent and the nucleus 41 has grown (see Fig. 4c),
If an alcoholate or a cationic inorganic compound is added to this reaction solution and these compounds are subjected to an addition reaction on the surface of the nucleus, as shown in Figure 4b,
A reactant 42 whose surface is positively charged is obtained. Inorganic pillar material 42 made in this way
In addition, an organic pillar material 51 made of a water-soluble polymer compound, a quaternary ammonium salt, etc. is used in combination, if necessary. When a colloidal inorganic compound is used as the inorganic pillar material, it may be used as it is as shown in Figure 4c, or the alcoholate or A reactant may be similarly obtained by adding a cationic inorganic compound and causing an addition reaction with these compounds on the surface of the core 41 made of the inorganic pillar material as in the previous case. Further, when the organic pillar material 51 is used in combination with the unmodified core 41, the result is as shown in FIG. 4a. A liquid mixture containing the above components is mixed with the swellable inorganic layered compound which has been swollen in advance, and inserted between the layers 1 and 1 of the layered compound (intercalation). The temperature during mixing is
In this invention, although not particularly limited, the temperature is preferably around 60 to 70°C. In addition, when a water-soluble polymer compound or quaternary ammonium salt is blended as an organic pillar material,
As shown in Fig. 5 a and b, this organic pillar material 5
1 serves to spread and hold the space between the layers 1 and 1, and at the same time sharpen the movement of the inorganic pillar materials 41 and 42 to hold the space between the layers 1 and 1. If no organic pillar material is added, the result will be as shown in Figure 5c. The retained inorganic pillar materials 41 and 42 thereby hold the space between the layers 1 and 1 while being expanded. In addition, when this inorganic pillar material is a reactant 42 whose surface is modified, the positive charge on its surface is electrically coupled to the negative portion on the surface of layer 1, as shown in FIG. 5b. and thereby layer 1,
It is thought that it will be possible to maintain the distance between 1 and 2 even wider. 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 includes not only a state exceeding the critical point but also a state just at the critical point. A method for creating a supercritical state is, for example, to directly heat and pressurize the solvent, such as water contained between the layers, held by the swellable inorganic layered compound to reach a state above its critical point. There is also a method of drying, but in such a method, the critical point of water is extremely high, with a critical temperature of 374.2°C and critical pressure of 217.6 atm, making the drying container large and highly dangerous. To avoid this, for example, after replacing the water in the swellable layered compound with ethanol, carbon dioxide is further added, and while gradually replacing ethanol with carbon dioxide, the mixture of carbon dioxide and ethanol is added. The supercritical state may be brought about by heating and pressurizing the component system to a temperature and pressure above the critical point. In this case, carbon dioxide above the critical point may be fed into the system to replace it. Drying is completed by allowing the fluid in a supercritical state to escape from the system. 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. hot air drying,
Alternatively, an inorganic porous material dried by freeze-drying has a significantly smaller pore volume than the inorganic porous material of the present invention. This is because the structure before drying cannot be well maintained. Although the above examples are also examples of the invention described in claims 6 and 7, the inorganic porous bodies having the configurations as described in claims 6 and 7 were prepared by a method other than the method described above (a method other than drying in a supercritical state). ) may be manufactured. Note that the fluids that can be used as solvents are not limited to those mentioned above. There are various substances that can be converted into critical fluids within a practical range, and examples thereof include ethanol, methanol, carbon dioxide, dichlorodifluoromethane, and ethylene. When the supercritical state is created, if supercritical conditions are selected and drying is performed, organic substances contained between the layers can be extracted into the supercritical fluid. Therefore, if an organic pillar material is inserted between the layers to expand and maintain the interlayer spacing, drying under appropriately selected supercritical conditions will extract only the organic pillar material. It becomes possible to remove it. In this way, the organic pillar material can be removed from the dried sample without baking it. The firing process can be omitted, and
This also solves the problem of carbon remaining between the layers after firing, which limits the use of catalytic activities. For reference, critical conditions for major fluids are shown in Table 1.

[Table] Next, specific examples and comparative examples according to the present invention will be explained. Example 1 Ethanol (special grade reagent, manufactured by Hanui Chemicals, Inc.) is added to alcoholate I, Si(OC ₂ H ₅ ) ₄ (manufactured by Hansui Chemicals, Inc.), and thoroughly mixed to form a solution. 2N hydrochloric acid was added to this solution and heated to 70°C to perform a hydrolysis reaction to create a core for an inorganic pillar material. Next, a 4M aqueous solution of TiCl ₄ (manufactured by Hanui Chemical Co., Ltd.), a cationic inorganic compound, is added to this solution and thoroughly mixed to cause a reaction, resulting in a reaction in which the reactants are dispersed. I got the liquid. This reaction solution was pre-swollen with water to form a swellable inorganic layered compound, Na-montmorillonite (Kunimine Kogyo Co., Ltd.).
Mixed with a 0.8% aqueous solution of Kunipia F), 60
The insertion reaction was carried out for 1.5 hours at °C. 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 for 8 hours while adding carbon dioxide (CO ₂ ), which has a relatively low critical point. , dried. The blending ratio of each component is a molar ratio, and Si
(OC ₂ H ₅ ) ₄ : Ethanol: 2N Hydrochloric acid: TiCl ₄ = 17:
18:65:1.7, Na-montmorillonite,
The blending ratio of SiO ₂ is 1:0.6 by weight. Example 2 2N hydrochloric acid was added to Ti(OC ₃ H ₇ ) ₄ (manufactured by Hanui Chemical Co., Ltd.), which is alcoholate I, and the mixture was heated to 70° C. to cause a hydrolysis reaction, thereby obtaining an inorganic pillar material solution. However, Ti(OC ₃ H ₇ ) ₄ :2N hydrochloric acid=1:12.5 (weight ratio). Next, this solution was mixed with 0.8% of Na-montmorillonite (Kunipia F manufactured by Kunimine Industries Co., Ltd.), which is a swellable layered compound that had been swollen with water in advance.
It was mixed with a wt% aqueous solution and an insertion 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 for 40 minutes while adding carbon dioxide, which has a relatively low critical point.
It was dried for 8 hours at 80 atm. The blending ratio of Na-montmorillonite and TiO ₂ was 1:0.6 by weight. Example 3 As an inorganic pillar material, a colloidal compound titania sol (Snowtech manufactured by Nissan Chemical Industries, Ltd.) was used.
An inorganic porous body was obtained in the same manner as in Example 2, except that TZK) was used. Example 4 2N hydrochloric acid was added to Ti(OC ₃ H ₇ ) ₄ (manufactured by Hanui Chemical Co., Ltd.), which is alcoholate I, and the mixture was heated to 70° C. to cause a hydrolysis reaction. However, Ti(OC ₃ H ₇ ) ₄ :2N hydrochloric acid=1:12.5 (weight ratio). Next, octadecyltrimethylammonium chloride (Cation AB, manufactured by NOF Corporation), which is a quaternary ammonium salt, was sufficiently mixed with this solution to obtain a mixed solution for an inorganic pillar material. This solution was mixed with a 0.8% aqueous solution of Na-montmorillonite (Kunipia F, manufactured by Kunimine Industries Co., Ltd.), a swelling layered compound, which had been swollen with water in advance, and an insertion reaction was carried out at 60°C for 1.5 hours. Ivy. After the reaction, repeated washing and centrifugation several times with ethanol, orientated into a plate shape with a spatula, and while adding carbon dioxide, which has a relatively low critical point,
It was dried for 8 hours at 80 atm. Example 5 As an inorganic pillar material, a 4 molar aqueous solution of TiCl ₄ (manufactured by Hanui Chemical Co., Ltd.), a cationic inorganic compound, was used as synthetic smectite (Kunimine), a swelling layered compound, which had been swollen with water in advance. Kogyo Co., Ltd.
The mixture was mixed with a 0.8% aqueous solution of Smecton SA (manufactured by Smecton SA), and an intercalation reaction was performed at 60°C for 1.5 hours. Except for this, an inorganic porous body was obtained in the same manner as in Example 2. Example 6 0.8% by weight of Na-montmorillonite (Kunipia F manufactured by Kunimine Industries Co., Ltd.) which is a swelling layered compound
An aqueous solution and a 10% aqueous solution of polyvinyl alcohol (PVA reagent manufactured by Hanui Chemical Co., Ltd., polymerization degree 500).
They were mixed at a weight ratio of 1:1 to perform an insertion reaction. After the reaction, repeated washing and centrifugation several times with ethanol, orientated into a plate shape with a spatula, and while adding carbon dioxide, which has a relatively low critical point,
It was dried for 8 hours at 80 atm. Example 7 0.8% by weight of Na-montmorillonite (Kunipia F manufactured by Kunimine Industries Co., Ltd.) which is a swelling layered compound
Prepare an aqueous solution, add about 5 ml of 2N hydrochloric acid to this solution, perform centrifugation several times, wash with ethanol several times, repeat centrifugation, orient it into a plate shape with a spatula, and cross the critical point of ethanol. It was dried for 72 hours at 270°C and 120 atm. Example 8 A 0.8% by weight aqueous solution of synthetic smectite (Smecton SA manufactured by Kunimine Factory Co., Ltd.), which is a swelling layered compound, and a 10% aqueous solution of polyvinyl alcohol (PVA, reagent manufactured by Hanui Chemical Co., Ltd., degree of polymerization 500), They were mixed at a weight ratio of 1:1 to perform an insertion reaction. After the reaction, washing with methanol and centrifugation were repeated several times, oriented into a plate shape with a spatula, and heated for 40 minutes while adding carbon dioxide, which has a relatively low critical point.
It was dried for 8 hours at 80 atm. Example 9 A 0.8% by weight aqueous solution of synthetic smectite (Smectone SA manufactured by Kunimine Industries Co., Ltd.), which is a swellable layered compound, was prepared, 2N hydrochloric acid was added to this solution, centrifuged several times, and then diluted with ethanol. Washing and centrifugation were repeated several times, oriented into a plate shape with a spatula, and dried at 40° C. and 80 atm for 8 hours while adding carbon dioxide, which has a relatively low critical point. Comparative Example 1 An inorganic porous body was obtained in the same manner as in Example 1, except that hot air drying at 60°C was used. Comparative Example 2 An inorganic porous body was obtained in the same manner as in Example 6, except that hot air drying at 60°C was used. Comparative Example 3 An inorganic porous body was obtained in the same manner as in Example 7, except that the drying was performed with hot air at 60°C. Comparative Example 4 A porous body made of commercially available coconut shell activated carbon was prepared. Regarding the porous bodies of Examples 1 to 9 and Comparative Examples 1 to 4, specific surface area, pore volume, apparent density, interlayer voids in inorganic compounds, voids between inorganic compounds (intercompound voids), thermal conductivity, and The odor characteristics (adsorption properties) were investigated. The results are shown in Tables 2 and 3. The specific surface area and pore volume are determined by the nitrogen adsorption method.
In the BET method, the interlayer void was determined by obtaining an X-ray diffraction measurement graph (see Figure 6) and performing d001 measurement. Regarding the voids between the inorganic layered compounds, the largest number of voids among the voids that appeared on the scanning electron micrograph of the surface of the porous body was recorded as the intercompound voids. Moreover, the thermal conductivity was measured by the heat flow meter method based on ASTM-C-518. In order to measure the deodorizing properties, the following two deodorizing experiments were conducted using trimethylamine or methyl mercaptan as the odor component. Experiment As shown in Figure 7, 0.3g of porous material 21 was put into a 300ml Erlenmeyer flask 20, and the stopper 22
Seal the mouth of flask 20 with. Next, 1 ml of trimethylamine (9.48% by volume) was injected, and after 1 minute, 0.5 ml was sampled and examined using a gas chromatograph. As a result of the analysis, if the odor has been completely eliminated (gas chromatograph measurement value 0 ppm), repeat the above operation, and if the odor is not completely eliminated, increase the time until sampling, and increase the time until the initial deodorization. Examined. Experiment As shown in Figure 7, 0.3g of porous material 21 was put into a 300ml Erlenmeyer flask 20, and the stopper 22
Seal the mouth of flask 20 with. Next, 5 ml of a 100-fold dilution of methyl mercaptan (9.16% by volume) was injected, left for 1 minute, UV irradiated, 1 ml sampled, and measured using a gas chromagraph. For the porous bodies of Examples 1 to 9 and Comparative Example 4, the UV irradiation time required to deodorize (gas chromatograph measurement value 0 ppm) was recorded. Regarding the inorganic porous bodies of Comparative Examples 1 to 3, the UV irradiation time and gas chromatograph measurement results until the measured values settled to a substantially constant low value are shown. The main equipment used for measurements etc. is as follows. Nitrogen adsorption method: Manufactured by Quantachrome, trade name: Autosoap 6

【table】

【table】

〔Effect of the invention〕

The inorganic porous bodies according to claims 1 to 5 maintain their porosity well before drying, have large pore volumes and sufficiently large voids, and therefore exhibit excellent adsorption and heat insulation properties. In the inorganic porous body according to claim 2, the inorganic pillar material used serves as a support and sufficiently expands the interlayer space, so that the inorganic layered compound has sufficient voids between the layers, and the pores are further expanded. It increases in volume and becomes more porous. In the inorganic porous body according to claim 3, the organic pillar material used serves as a support and the interlayers are sufficiently expanded, so that the inorganic layered compound has sufficient voids between the layers, and the inorganic layered compound becomes even more porous. The pore volume increases,
Porous. Furthermore, the organic pillar material itself is very preferable because it does not require a firing process and no carbon content remains in the inorganic porous body. In the invention according to claims 4 and 5, the fluid contained in the swellable inorganic layered compound in a swollen state is not water with a high critical point. Therefore, it is easy to create a supercritical state, which is very convenient for manufacturing. The inorganic porous body according to claim 6 is a card house-like or sponge-like aggregate of inorganic layered compounds in the shape of flower petals or cicada feathers, and has sufficient voids between the inorganic layered compounds. As a result, it has sufficient pore volume and porosity, and exhibits excellent adsorption and heat insulation properties. In the inorganic porous body according to claim 7, the inorganic layered compound has a pore distribution with a peak in the range of at least 100 nm to several nanometers between each other, and has a sufficient pore volume, and When there are many voids within a range, there are many types of particles that can be effectively adsorbed, making it versatile (wide range of uses). In the inorganic porous body according to claims 8 and 9, the inorganic layered compound has sufficient voids between the layers, and the pore volume is increased, and small particles that cannot be captured in the voids between the compounds can be effectively adsorbed. .

[Brief explanation of drawings]

Figure 1 is a scanning electron micrograph (20,000x magnification) showing the particle structure of the inorganic layered compound on the surface of the inorganic porous body of the present invention, and Figure 2 is the structure of the inorganic layered compound in the inorganic porous body of the present invention. FIG. 3 is a schematic illustration showing how an inorganic layered compound is swollen. FIG. 4a is a schematic illustration showing a solution containing an inorganic pillar material and an organic pillar material. Figure 4b is
FIG. 4c is a schematic explanatory diagram showing a solution containing a surface-modified inorganic pillar material and an organic pillar material.
A schematic illustration showing a solution containing only an inorganic pillar material, FIG. 5a is a schematic illustration showing an inorganic layered compound in a swollen state into which the inorganic pillar material of FIG. A schematic explanatory diagram showing an inorganic layered compound in a swollen state with an inorganic pillar material and an organic pillar material inserted in FIG. 4b, and FIG. 5c
is a schematic illustration of the inorganic layered compound in a swollen state with the inorganic pillar material and organic pillar material inserted in FIG. Line diffraction measurement graph, Figure 7 is an explanatory diagram showing the state during deodorization experiment, and Figure 8 is a scanning electron micrograph (magnification: 2) showing the particle structure of an inorganic layered compound on the surface of a conventional inorganic porous material. 10,000 times). A: inorganic layered compound, 1: layer of inorganic layered compound, 2: void, 3: solvent, 4: inorganic pillar, 41, 42: inorganic pillar material, 51: organic pillar material.

Claims (1)

[Scope of Claims] 1. An inorganic porous material obtained by drying a swellable inorganic layered compound in a swollen state in a supercritical state. 2. Claim 1, wherein the swellable inorganic layered compound is dried with an inorganic pillar material whose surface is modified with at least one selected from a cationic inorganic compound and an alcoholate inserted between its layers. The inorganic porous material described. 3. The method according to claim 1, wherein the swellable inorganic layered compound is dried with an organic pillar material inserted between the layers, and at the same time, the pillar material is removed from between the layers during the drying. Inorganic porous material. 4. Any one of claims 1 to 3, wherein the fluid contained in the swellable inorganic layered compound in a swollen state is at least one selected from ethanol, methanol, carbon dioxide, and dichlorodifluoromethane. The inorganic porous material described. 5. Any one of claims 1 to 3, wherein the drying is performed by replacing water contained in the swellable inorganic layered compound in a swollen state with ethanol, and then replacing this ethanol with carbon dioxide. The inorganic porous body described in . 6. An inorganic porous material formed by petal-like or cicada-like feather-like inorganic layered compounds brought together to form a card house-like or sponge-like aggregate. 7 The inorganic layered compounds have at least
An inorganic porous material that has a pore distribution with a peak in the range of 100 nm to several thousand nm. 8 The inorganic layered compound has a thickness of several nanometers to several nanometers between the layers.
The inorganic porous material according to claim 7, having a void distribution with a peak in the 10 nm range. 9. The inorganic porous body according to any one of claims 6 to 8, wherein the inorganic layered compound has pillars inserted between its layers.