JP4701437B2 - Aromatic compound-layered inorganic compound porous body and method for producing the same - Google Patents

Description

  The present invention relates to an aromatic compound-layered inorganic compound porous body that can be used as an adsorbent for various substances, a catalyst carrier, a light-shrinkable material, and the like, and a method for producing the same, and further, the aromatic compound-layered inorganic compound The present invention relates to an adsorbent containing a porous body, a catalyst carrier, and a photostretchable material.

  Conventionally, inorganic porous bodies such as zeolite, layered cross-linked body (pillared clay), amorphous silica, MCM-41, etc. have pores with various nano-sized shapes, so adsorption for capturing specific molecules It is used as an agent, catalyst carrier and gas storage. In recent years, in order to improve the ability to collect environmental hormones, bioorganic substances, and low molecular organic gases in the environmental field, biotechnology field, and energy field, the development of inorganic porous materials incorporating aromatic hydrocarbons and their derivatives in the inorganic skeleton has been developed. It is done. To date, zeolite-like compounds, amorphous silica, and mesoporous silica-like compounds known as MCM-41 have been synthesized.

  For example, as a method for obtaining a zeolite-like compound, a metal complex having a dicarboxylic acid-containing aromatic compound (transdicarboxylic acid, stilbene dicarboxylic acid, terphenyl dicarboxylic acid, etc.) as a ligand is used as a constituent unit. A method for producing a zeolite-like network structure by association or polymerization (Patent Document 1, Patent Document 2, Patent Document 3, and Patent Document 4) is disclosed. The resulting complex polymer has a 1-3-dimensional channel structure, and the channel wall surface is composed of an aromatic hydrocarbon derived from a ligand.

  Further, as a method for obtaining amorphous silica, bis (alkoxysilyl) aryl compounds (for example, 1,4-bis (triethoxysilyl) benzone, 4,4-bis (triethoxy) biphenyl), etc. are used, and hydrolysis of alkoxysilane is performed. A method of causing condensation (sol-gel method) to produce amorphous silica has been reported (Non-Patent Document 1). In addition, a method of synthesizing an MCM-41 type compound by introducing a structure directing agent such as a surfactant during the reaction has been reported (Non-patent Document 2). The pore wall surface of the obtained silica is formed of organic silica containing aromatic hydrocarbons derived from bis (alkoxysilyl) aryl compounds as constituent elements.

The porous layered compound crosslinked body is an inorganic adsorbent widely used as an adsorbent and a catalyst for both zeolite and silica. The specific surface area is an inorganic porous body having 10 to 1000 m ² / g, and is obtained by cross-linking layers between clay mineral layers by a material that maintains the layers (hereinafter referred to as pillar materials). Therefore, many porous layered compound crosslinked bodies have been synthesized by changing the pillar material made of an inorganic oxide (Patent Document 5). Moreover, in order to improve the adsorptivity of organic substances, such as an aromatic compound, the porous layered compound which inserted the aromatic compound cation as a pillar substance is synthesize | combined (patent document 6). However, the inserted aromatic compound cations are weakly adsorbed by the electrostatic interaction, and are adsorbed in an orientation state that is affected by the interaction between layers and minimizes the gap between the layers. There was a problem of doing (see FIG. 1). Therefore, the space | gap between layers was limited and the porosity was low. In addition, the aromatic compound cation is eluted out of the system during the adsorption reaction. In order to eliminate such drawbacks, it is necessary to bind and fix an aromatic compound to both surfaces between layers via a cross-linking molecule to suppress the formation of a specific alignment structure. However, a crosslinked aromatic compound having such a structure has not been known.
JP 2000-63385 A JP 2000-109493 A JP 2000-109485 A JP 2000-178279 A JP-A-4-238810 JP 2001-261329 A JOURNAL OF AMERICAN CHEMICAL SOCIETY, VOL114, PP6700-6710, 1992 Nature, VOL416, PP304-307, 2002

  Therefore, the main object of the present invention is to provide a layered inorganic compound porous body in which an aromatic compound is fixed between layers of a layered inorganic compound, and a method for producing the same. It is another object of the present invention to provide an adsorbent, a catalyst carrier and a photostretchable material containing such an aromatic compound-layered inorganic compound porous body.

  As a result of earnest research for the novel materials that can be used as functional materials including adsorbents, catalyst carriers, and photostretchable materials that adsorb various substances, the present inventors have obtained aromatic compounds. In a solution containing (for example, a bis (alkoxysilyl) aryl compound), an aromatic compound residue is fixed between layers of a layered inorganic compound through a crosslinking site by mixing a layered inorganic compound having an expanded layer in advance. Moreover, the aromatic compound-layered inorganic compound porous body was obtained, and the present invention was completed.

That is, the present invention relates to the following matters.
Item 1. Aromatic compound-layered inorganic compound porous body, characterized in that an aromatic compound residue is fixed between layers of a layered inorganic compound through two cross-linking sites. Item 2. The aromatic compound-layered inorganic compound porous material according to Item 1, wherein the aromatic compound residue is an arylene group, a substituted arylene group, or a heterocyclic aromatic compound residue containing a nitrogen or sulfur atom. Item 3. An aromatic compound-layered inorganic compound porous body having a crosslinking site containing a silicon atom,
The following formula (1)

(Here, A ¹ and A ² are unit layers of a layered inorganic compound (A ¹ and A ² may be different from each other or the same), and —O—Si (Z ¹ ) In the _two cross-linking sites represented by 2- or -O-Si (Z ² ) _2- , Z ¹ is R ¹ , OR ² or OA ¹ , and Z ² is R ¹ , OR ² or OA ² (wherein R ¹ is hydrogen, an alkyl group, an alkenyl group, an aminopropyl group, a mercaptopropyl group, a glycidyloxypropyl group, a mercapto group, or a sulfide group, and R ² is hydrogen, an alkyl group, An alkenyl group, aminopropyl group, mercaptopropyl group, glycidyloxypropyl group, mercapto group or sulfide group, and A ¹ and A ² are as defined above), the aromatic compound residue R ³ is Arylene group Item 3. The aromatic compound-layered inorganic compound porous body according to Item 1 or 2, which has a partial structure represented by a substituted arylene group or a heterocyclic aromatic compound residue containing a nitrogen or sulfur atom.
Item 4. Item 4. The aromatic compound-layered inorganic compound porous body according to Item 3, wherein the partial structure represented by the formula (1) has a multimeric structure generated by polymerization.
Item 5. Item 5. The aromatic compound-layered inorganic compound porous body according to Items 1 to 4, wherein the layered inorganic compound is a cation exchangeable layered inorganic compound.
Item 6. The following formula (2)

(Where R ¹ is hydrogen, an alkyl group, an alkenyl group, an aminopropyl group, a mercaptopropyl group, a glycidyloxypropyl group, a mercapto group, or a sulfide group, and R ² is hydrogen, an alkyl group, an alkenyl group, an amino group, A propyl group, a mercaptopropyl group, a glycidyloxypropyl group, a mercapto group or a sulfide group, and R ³ is an arylene group, a substituted arylene group, or a heterocyclic aromatic compound residue containing a nitrogen or sulfur atom, and m = Bis (alkoxysilyl) represented by an integer of 1 to 3, and n = 1 to 3 (wherein n and m may be the same or the same). Item 6. The aromatic compound according to Item 1 to 5, which comprises a step of mixing a solution containing an aryl compound and a layered inorganic compound having previously expanded layers. Method for producing a layered inorganic compound porous body.
Item 7. Item 7. The production method according to Item 6, wherein the layered inorganic compound with the interlayer expanded in advance is a cation-exchangeable layered inorganic compound with the layer expanded in advance.
Item 8. Item 6. An adsorbent comprising the aromatic compound-layered inorganic compound porous material according to Items 1 to 5.
Item 9. Aromatics as set forth in claim 1 to 5 having a further catalyst during the unit layer A ¹ and A ² - containing a layered inorganic compound porous catalyst support.
Item 10. Item 6. An optical stretchable material comprising the aromatic compound-layered inorganic compound porous body according to Item 1-5.

  The invention will be described in more detail below.

  The layered inorganic compound may be any mineral as long as it has a layered structure, clay, and other inorganic compounds. The layered inorganic compound may be a natural product or an artificial synthetic product. Further, as the layered inorganic compound, a cation-exchangeable layered inorganic compound is particularly preferable, but those other than cation-exchangeable are also included. Examples of the layered inorganic compound include silicate minerals and clay minerals having a cation exchange ability such as isallite, magadiite, kanemite, montmorillonite, hectorite, vermiculite, mica compound, phlogopite, biotite, talc. , Silicate minerals and clay minerals that do not have cation exchange capacity such as hydrotalcite, manganese oxides such as banesite, inorganic compounds such as titanium oxide, and mixed layer inorganic compounds, but other than these Inorganic compounds can be used as well.

  The aromatic compound residue is not particularly limited as long as it is an organic compound residue that exhibits aromaticity and can be fixed between layers of a layered inorganic compound via a crosslinking site. For example, an arylene group, a substituted arylene group, or nitrogen Or a heterocyclic aromatic compound residue containing a sulfur atom, and as an arylene group, a phenylene group, a biphenylene group, a terphenylene group, a naphthylene group,

(Where a is O, CH ₂ , NH, N═N or C═O), or

(Where b is O, CH ₂ , NH, N═N or C═O, and c is O, CH ₂ , NH, N═N or C═O). These include compounds in which one or more functional groups such as a sulfonic acid group, a thiol group, a carboxylic acid group, an alkyl group, an alkoxy group, a hydroxyl group, an acyl group, a cyano group, and a halogen group are substituted. Furthermore, the heterocyclic aromatic compound residue containing a nitrogen or sulfur atom includes a divalent group such as pyridine, 2,2′-bipyridyl, 1,10-phenanthroline, quinoline, oxine, thiophene or thiophene polymer.

  The cross-linking site is a site for bonding the opposing unit layer of the layered inorganic compound and the aromatic compound residue, and may be any as long as the unit layer and the aromatic compound residue can be bonded and fixed. The crosslinking site is a chemical bond such as -O-, -OCONH-, -O-Si-, -O-Ti-, etc., produced by the reaction.

In the above formula (1), A ¹ and A ² are unit layers of a layered inorganic compound, and A ¹ and A ² may be different from each other or the same. When A ¹ is the same as A ² , it is a layered structure in which one type of unit layer is overlapped. When A ¹ is different from A ² , it is a mixed layered structure in which different unit layers are overlapped.

  The aromatic compound-layered inorganic compound porous body having a partial structure represented by the above formula (1) is an aromatic compound-layered inorganic compound porous body having at least a part of the structure. For example, in a multi-layer structure composed of two or more unit layers, at least two unit layers in the multi-layer structure at least partially have a structure represented by the above formula (1). Moreover, the partial structure represented by Formula (1) may exist uniformly (or regularly), or may exist unevenly (or irregularly). In other words, the partial structure represented by Formula (1) may be scattered randomly in the entire structure, may exist locally, or may be distributed uniformly. Further, a large amount of two or more adjacent partial structures represented by the formula (1) that are present between the layers are polymerized in the horizontal (parallel) direction with the unit layer via the silicon atom and the oxygen atom in the formula (1). It may take a body structure. At this time, a part (one or more, but not all) of the polymerizable functional groups in the partial structure may be polymerized, or all the polymerizable functional groups may be polymerized. The multimeric structure may be present uniformly (or regularly) or non-uniformly (or irregularly).

In the above formula (1), Z ¹ is R ¹ , OR ² or OA ¹ , and Z ² is R ¹ , OR ² or OA ² .

R ¹ is hydrogen, an alkyl group, an alkenyl group, an aminopropyl group, a mercaptopropyl group, a glycidyloxypropyl group, a mercapto group, or a sulfide group. Here, examples of the alkyl group include (but are not limited to) methyl, ethyl, propyl, butyl and the like, and examples of the alkenyl group include a vinyl group, an allyl group, a 2-propenyl group, a 1-butenyl group, and 2-butenyl. Group, 3-butenyl group, and the like can be exemplified (but not limited to).

R ² is hydrogen, an alkyl group, an alkenyl group, an aminopropyl group, a mercaptopropyl group, a glycidyloxypropyl group, a mercapto group, or a sulfide group. Examples of the alkyl group include (but are not limited to) methyl, ethyl, propyl, butyl and the like, and examples of the alkenyl group include a vinyl group, an allyl group, a 2-propenyl group, a 1-butenyl group, a 2-butenyl group, 3 -A butenyl group etc. can be illustrated (it is not limited to these).

R ³ is an arylene group, a substituted arylene group or a heterocyclic aromatic compound residue containing a nitrogen or sulfur atom. Examples of the arylene group include a phenylene group, a biphenylene group, a terphenylene group, a naphthylene group,

(Where a is O, CH ₂ , NH, N═N or C═O), or

(Where b is O, CH ₂ , NH, N═N or C═O, and c is O, CH ₂ , NH, N═N or C═O), etc. Not limited).

Moreover, the substance which can adsorb | suck to the aromatic compound-layered inorganic compound porous body of the present invention is determined by various properties such as bulkiness and polarity of R ³ . For example, if R ³ has a large structure, small substances will be able to be adsorbed suitably, and if R ³ is totally or partially polar, it has a polarized part in the molecule. The material will preferably adsorb.

  The aromatic compound-layered inorganic compound porous body of the present invention can be in a state in which the interlayer aromatic compound is bonded to the layered inorganic compound via an oxygen atom. As a mechanism of this bonding, for example, when the aromatic compound is a bis (alkoxysilyl) aryl compound, the alkoxide group of the bis (alkoxysilyl) aryl compound is hydrolyzed and the hydroxyl group present in the inserted layer It is thought to be a polymer bond. In addition, some of the aromatic compounds in the interlayer can be polymerized with each other via a hydroxyl group to form a multimer. The aromatic compound improves the mechanical stability as a pillar due to the formation of the multimer, and more stably holds the interlayer.

  Such an aromatic compound-layered inorganic compound porous body of the present invention is basically produced by mixing a solution containing an aromatic compound and a layered inorganic compound having previously expanded layers.

  Examples of the aromatic compound suitably used as a raw material in the production of the aromatic compound-layered inorganic compound porous body of the present invention include an aryl compound, a substituted aryl compound, and a heterocyclic aromatic compound containing a nitrogen or sulfur atom. Examples of the aryl compound include bis (alkoxysilyl) aryl compounds.

In the method for producing an aromatic compound-layered inorganic compound porous body of the present invention, a bis (alkoxysilyl) aryl compound suitably used as a raw material is represented by the above formula (2), in which R ¹ is hydrogen. An alkyl group, an alkenyl group, an aminopropyl group, a mercaptopropyl group, a glycidyloxypropyl group, a mercapto group, or a sulfide group. Here, examples of the alkyl group include (but are not limited to) methyl, ethyl, propyl, butyl and the like, and examples of the alkenyl group include a vinyl group, an allyl group, a 2-propenyl group, a 1-butenyl group, and 2-butenyl. Group, 3-butenyl group and the like can be exemplified (but not limited to).

R ² is hydrogen, an alkyl group, an alkenyl group, an aminopropyl group, a mercaptopropyl group, a glycidyloxypropyl group, a mercapto group, or a sulfide group. Examples of the alkyl group include (but are not limited to) methyl, ethyl, propyl, butyl and the like, and examples of the alkenyl group include a vinyl group, an allyl group, a 2-propenyl group, a 1-butenyl group, a 2-butenyl group, 3 -A butenyl group etc. can be illustrated (it is not limited to these).

R ³ is an arylene group, a substituted arylene group or a heterocyclic aromatic compound residue containing a nitrogen or sulfur atom. Examples of the arylene group include a phenylene group, a biphenylene group, a terphenylene group, a naphthylene group,

(Where, a _{is, O, CH 2, NH,} N = N, a C = O),

(Where b is O, CH ₂ , NH, N = N, C = O, and c is O, CH ₂ , NH, N = N, C = O), etc. Not limited). These include compounds in which one or more functional groups such as a sulfonic acid group, a thiol group, a carboxylic acid group, an alkyl group, an alkoxy group, a hydroxyl group, an acyl group, a cyano group, and a halogen group are substituted. Furthermore, the heterocyclic aromatic compound residue containing a nitrogen or sulfur atom includes a divalent group such as pyridine, 2,2′-bipyridyl, 1,10-phenanthroline, quinoline, oxine, thiophene or thiophene polymer.

  In the formula (2), m is an integer of 1 to 3, n is an integer of 1 to 3, and n and m may be different from each other or the same. As the number of m or n is larger, the number of sites bonded to the layered inorganic compound via oxygen atoms is increased, and stronger crosslinks can be formed.

  The molecular length of the aromatic compound is in the range of 0.01 to 20 nm, preferably 0.1 to 7 nm, more preferably 0.3 to 2 nm.

  In addition, the layered inorganic compound that is a raw material of the layered inorganic compound whose layers are expanded in advance may be any mineral, clay, or other inorganic compound having a layered structure. As the layered inorganic compound as the raw material, a cation-exchangeable layered inorganic compound is particularly preferable, but a layered inorganic compound having no cation-exchange ability can be used as well. In addition, the layered inorganic compound that is a raw material of the layered inorganic compound whose layers have been expanded in advance may be a natural product or an artificially synthesized product. The layered structure may be a layered structure in which one type of unit layer overlaps or may be a mixed layered structure in which two or more different unit layers overlap. Examples of the layered inorganic compound as the raw material as described above include silicate minerals, clay minerals, gold minerals having cation exchange ability such as isallite, magadiite, kanemite, montmorillonite, hectorite, vermiculite, mica compound and the like. Examples include mica, biotite, talc, hydrotalcite and other inorganic compounds such as silicate minerals and clay minerals, manganese oxides, titanium oxides and the like, and mixed layer inorganic compounds thereof. Inorganic compounds other than these can be used similarly.

  The mixing of the solution containing the aromatic compound and the layered inorganic compound whose layer is expanded in advance depends on the type of the aromatic compound used, the type of the layered inorganic compound whose layer is expanded in advance, the blending ratio thereof, and the like. Alternatively, heating, cooling, or stirring may be performed as appropriate. The mixing time is not particularly limited as long as the reaction is sufficiently advanced, but is, for example, 1 hour to 7 days, preferably 5 hours to 3 days, and more preferably 10 hours to 2 days. In order to further advance the reaction, the solution may be separated after completion of mixing, and the solid component may be dried. The drying time is, for example, 3 hours to 10 days, more preferably 12 hours to 5 days. Moreover, you may irradiate a microwave at the time of drying. Thereafter, in order to further remove the intercalation material (intercalant) (described in detail below) used to prepare a layered inorganic compound having previously expanded layers, for example, water, alcohol, acid aqueous solution, acid alcohol, Process using supercritical carbon dioxide.

  The acid used at this time is preferably an inorganic acid such as hydrochloric acid, nitric acid, sulfuric acid or phosphoric acid, but may be an organic acid such as formic acid or acetic acid. As the alcohol, lower alcohols such as methyl alcohol, ethyl alcohol, propyl alcohol, and butyl alcohol are preferably used, but alcohols other than these can also be used.

  Instead of such treatment with water, alcohol, aqueous acid solution or acid alcohol, carbon dioxide in a supercritical state can be used. In this case, supercritical carbon dioxide obtained by bringing carbon dioxide into a supercritical state is brought into contact with a layered inorganic compound containing an aromatic compound between layers. This supercritical state of carbon dioxide is brought about by, for example, maintaining carbon dioxide at a temperature of 35 to 50 ° C. and a pressure of 10 to 40 MPa. Since this supercritical carbon dioxide has low viscosity, small surface tension, and high diffusivity, it can penetrate throughout the layers of the layered compound and extract the intercalant efficiently.

By such removal of the intercalant, the portion occupied by the intercalant becomes pores, and an aromatic compound-layered inorganic compound porous body excellent in porosity is obtained.
FIG. 2 shows a schematic diagram for facilitating understanding of the method for producing the aromatic compound-layered inorganic compound porous body of the present invention. This diagram simply represents the production method of the present invention. It should be understood that it is only.

  A layered inorganic compound whose layers are expanded in advance is obtained by inserting (intercalating) an insertion substance (intercalant) between layers of the layered inorganic compound as a raw material. Intercalation can be performed, for example, by allowing a solution containing an intercalant to act directly on the raw layered inorganic compound and then leaving it for a while (eg, 1 to 48 hours). Examples of intercalants include (but are not limited to) alkylamines, alkylammonium ions, alkylphosphonium ions, pyridinium ions, alkylcarboxylic acid ions, alkylsulfuric acid ions, alkylbenzenesulfonic acid ions, and the like.

  The amount of intercalant dropped is not particularly limited as long as intercalation can sufficiently occur, but when the raw layered inorganic compound is ion exchangeable, for example, the ion exchange capacity of the layered compound 1 to 50 times, preferably 3 to 30 times, more preferably 8 to 15 times.

As the alkylamine, for example, a primary alkylamine (wherein the alkyl group is a C _{1 to} C ₁₂ linear or branched alkyl group) can be preferably used. When a primary alkylamine is used, it is particularly desirable to exchange the interlayer ions of the layered compound with protons (H ⁺ ions) before dropping them. The exchange of protons is performed by immersing Ilarite in an aqueous acid solution such as hydrochloric acid or nitric acid, stirring, and then washing with water. At this time, the concentration of hydrochloric acid is 0.001 to 10 mol / l, preferably 0.01 to 5 mol / l, and more preferably 0.1 to 1 mol / l. Further, the amount of protons in the aqueous solution is adjusted so as to be larger than the amount of ion exchange sites contained in the Ilarite. The amount of protons at this time is 1.1 to 1000, preferably 2 to 100, more preferably 5 to 10 times the amount of ion exchange sites. As a method of immersing the illite in the acid aqueous solution, the acid aqueous solution and the illite may be mixed at once, or after the illite is previously dispersed in water, the acid aqueous solution may be dropped dropwise and mixed. good. After mixing, stirring is performed for a certain time, and the stirring time is in the range of 0.5 to 1000 hours, preferably 2 to 100 hours, more preferably 12 to 50 hours. Further, after the stirring treatment, washing is performed with water. At this time, washing is performed well so that chloride ions, nitrate ions, and the like, which are components of the used acid, do not remain.

  Examples of the alkyl ammonium ion include the following formula (3):

(Wherein R ₁ , R ₂ , R ₃ and R ₄ are alkyl groups, and X- is an anion residue such as a hydroxide ion or a halogen ion). . When quaternary ammonium ions are used as an intercalant, for example, a solution is prepared by dissolving a quaternary ammonium compound in water or an organic solvent, and a cation exchange layered inorganic compound is immersed in this solution, and if necessary, 50 Cation exchange for 1 to 12 hours while heating to ˜90 ° C., solids separated by filtration, washed with water or alcohol, and dried to expand the cation exchange layered inorganic in advance A compound can be produced (Japanese Patent Laid-Open No. 4-74708).

  The length of the intercalant is selected so that the gap distance between the layers of the layered inorganic compound intercalated with the intercalant is substantially the same as or slightly longer than the length of the long axis of the aromatic compound to be inserted. Is desirable. Therefore, the length of the intercalant is in the range of 0.01 to 20.5 nm, preferably 0.1 to 7.5 nm, more preferably 0.3 to 2.5 nm. Further, the interlayer distance of the layered inorganic compound expanded between the layers by the intercalant is considered to be substantially the same as the length of the intercalant.

  In addition, a functional group can also be substituted and introduced with respect to the aromatic residue in the obtained reaction product. This introduction can be usually performed by a method of introducing a functional group into an aromatic compound. Examples of functional groups that can be introduced by conventional methods include one or more of sulfonic acid groups, thiol groups, carboxylic acid groups, alkyl groups, alkoxy groups, hydroxyl groups, acyl groups, cyano groups, halogen groups, and the like.

  The structure of the reaction product thus obtained can be evaluated by measurement of interlayer distance by X-ray diffraction method, specific surface area or pore measurement by gas adsorption method. In addition, whether the aromatic compound is polymerized in the reaction product can be determined by analyzing the decrease in hydroxyl groups bonded to silicon atoms, increase in siloxane bonds, and the bonding state of silicon-carbon atoms by solid state NMR. . In addition, whether or not aromatic compounds are arranged between layers can be indirectly known by excimer observation by fluorescence emission analysis or the like. Further, whether or not the aromatic compound is cross-linked can be confirmed by whether or not the interlayer distance increases when an organic compound or the like is adsorbed.

  Moreover, the aromatic compound-layered inorganic compound porous body of the present invention can be used as various functional materials.

  The aromatic compound-layered inorganic compound porous body of the present invention can be used as an adsorbent for various substances. In general, the adsorption capacity of an adsorbent is determined by the specific surface area, the pore volume, the chemical properties of the adsorbent, and the like.

  The adsorbent containing the aromatic compound-layered inorganic compound porous material produced by the method of the present invention is used for adsorbing various substances. At this time, an aromatic compound interposed between layers is designed according to the properties (for example, size, shape, chemical properties (polarity, electrostatic properties, etc.)) of the substance to be adsorbed, and this is layered according to the present invention. It can be present between layers of inorganic compounds. In designing an aromatic compound or derivative thereof, for example, the number of rings of the aryl moiety and the nature of the substituents attached to the ring (eg, polarity, bulkiness, etc.) will be considered. The porosity (the size and number of pores) may be changed according to the size and number of substances to be adsorbed. For example, the size and number of pores can be changed by changing the amount of intercalant used when expanding the layers in advance or other intercalation conditions. For example, if the substance to be adsorbed is a relatively large molecule (for example, an environmental hormone substance such as DDT, dioxin, PCB, bisphenol A, etc.), relatively large pores that can adsorb such a molecule. In order to form the intercalation conditions, the intercalation conditions can be changed as appropriate. The adsorbent containing the porous body of the present invention thus obtained has high selectivity for the substance to be adsorbed.

  As described above, the adsorbent of the present invention capable of selective adsorption can adsorb various substances, for example, organic substances, gases and the like can be favorably adsorbed. Can be adsorbed. Examples of organic substances include environmental hormone substances such as DDT, dioxin, PCB, and bisphenol A, aromatic amino acids such as tryptophan, phenylalanine, and tyrosine, amino acid polymers such as DNA, RNA, and proteins, adrenaline and histamine, Examples include physiologically active substances such as dopamine, monosaccharides such as glucosamine, galactosamine, and ribofuranose, polysaccharides such as maltose and sucrose, and bioorganic substances such as interferon, steroid, and cholesterol (not limited to these). ). Examples of the gas include nitrogen, hydrogen, oxygen, propane, and methane. In addition to these, various gases that require adsorption, such as fuel gas and toxic gas, can be used. Hydrogen can be efficiently adsorbed on the adsorbent of the present invention and used as a material for a hydrogen battery or the like. The hydrogen battery can be used, for example, as a vehicle part such as an automobile using hydrogen as a fuel supply source.

  Furthermore, since the adsorbent as described above can adsorb molecules of a specific size or property, it can also be used when separating and purifying only the target substance from the mixture. Separation and purification can be performed, for example, by immersing the adsorbent of the present invention in a solution containing a mixture, washing the adsorbent to remove unnecessary substances, and extracting a target substance using an appropriate solution.

  In addition, a catalyst may be further supported or fixed between the layers of the aromatic compound-layered inorganic compound porous body of the present invention and used as a catalyst carrier. Examples of the catalyst include metal catalysts (for example, platinum catalyst, nickel catalyst, rhodium catalyst, cobalt catalyst, chromium catalyst, iron catalyst, ruthenium catalyst, osmium catalyst, vanadium catalyst), complex catalysts (for example, Wilkinson complex, metallocene complex), etc. Although it can be considered, any catalyst other than these can be used as long as it can be supported on the layer.

  The target for using the catalyst carrier of the present invention may be any substance, but preferably includes a substance having affinity for an aromatic compound present between layers. For example, when a bis (alkoxysilyl) aryl compound is present between layers, a substance having an aryl group that has an affinity for the bis (alkoxysilyl) aryl compound can be used. Thus, a substance having an affinity for the bis (alkoxysilyl) aryl compound approaches the bis (alkoxysilyl) aryl compound between the layers, and acts as a catalyst existing near the bis (alkoxysilyl) aryl compound. It is thought to cause a reaction.

  Moreover, in this invention, a stereoisomer is changed by irradiation of light as an aromatic compound residue.

If such a group is employed, an aromatic compound-layered inorganic compound porous body that shrinks by light can be obtained. Such a photoshrinkable aromatic compound-layered inorganic compound porous body is used as a raw material of a photoshrinkable material. Such light-shrinkable materials can be used, for example, in drug delivery systems that are used to effectively utilize drug activity. For example, it becomes a material for producing a drug from which an active ingredient is released by irradiation with light.

  The adsorbent containing the aromatic compound-layered inorganic compound porous material of the present invention, the catalyst carrier, and the light-shrinkable material take various shapes, for example, a film shape, a sheet shape, a powder shape, and a fine particle shape (not limited to these). ). Moreover, it is good also as a molded object (for example, granular form, tablet form, clay form, slurry form) using a suitable binder. Such adsorbents, catalyst supports and light-shrinkable materials contain various additives (eg, dyes, extenders, photosensitizers) to impart desired properties or improve utility. You may go out.

  According to the present invention, a novel aromatic compound-layered inorganic compound porous body and a method for producing the same are provided. In the aromatic compound-layered inorganic compound porous body of the present invention, the aromatic structure is strongly fixed between the layers by the cross-linked site, so that the orientation structure is hardly affected by the interaction between the layers. Therefore, a gap between layers is maintained. As a result, this porous body is a substance excellent in porosity and substance adsorption, and is also useful as a raw material for adsorbents, catalyst carriers, and light-shrinkable materials. Moreover, the adsorbent containing the aromatic compound-layered inorganic compound porous body of the present invention can also selectively adsorb a substance to be adsorbed.

  The following examples are merely illustrative for explaining the present invention in more detail, and do not limit the present invention in any way.

1. Synthesis of Proton Exchange Type Ilarite (Polysilicic Acid) 2 g of silica gel and 4 ml of 4 mol / l sodium hydroxide aqueous solution were sealed in a glass container and reacted in a hot air drier maintained at 106 ° C. for 9 days. After the reaction, the resulting white precipitate was washed and dried in a dryer at 50 ° C. for 2 days. 1 g of dried Ilarite was suspended in 30 ml of distilled water and stirred at a speed of 200 rpm. Furthermore, 40 ml of 0.1 mol / l hydrochloric acid aqueous solution was dropped at a rate of 1.6 × 10 ⁻² ml per minute while stirring. After dropping, the mixture was stirred for 1 day and then filtered. The obtained white precipitate was dried in a dryer at 50 ° C. for 2 days.

2. Synthesis of 4,4′-bis (triethoxysilyl) biphenyl 3 g of magnesium was placed in a measuring flask and dried under reduced pressure. Furthermore, 75 ml of tetrahydrofuran and 50 ml of tetraethoxyorthosilicate were added to 10 g of 4,4′-dibromobiphenyl dried under reduced pressure to prepare a solution. This prepared solution was added into a volumetric flask containing magnesium, and the mixture was refluxed at 75 ° C. for 5 days. After refluxing, the mixture was cooled to room temperature, and tetrahydrofuran was removed at a temperature of 40 ° C. under reduced pressure using an evaporator. 20 ml of n-hexane was added to the precipitate and filtered under a nitrogen atmosphere. Thereafter, n-hexane and tetraethoxyorthosilicate were removed from the filtered solution under reduced pressure using an evaporator. The resulting solution was distilled at 240 ° C. under reduced pressure. After distillation, a transparent liquid 4,4′-bis (triethoxysilyl) biphenyl was obtained.

3. Synthesis of Ilarite Crosslinked by Biphenyl Compound 200 mg of proton-exchanged Ilarite was placed in a Teflon (registered trademark) centrifuge tube, added with 1.2 ml of hexylamine, sealed and allowed to stand for 2 days. Two days later, a solution of 0.5 ml of 4,4′-bis (triethoxysilyl) biphenyl dissolved in 10 ml of n-hexane was prepared, poured into a Teflon (registered trademark) centrifuge tube, and stirred at a speed of 300 rpm. Stir for 7 days. After stirring, the solution was removed and dried at room temperature for 5 days. After drying, 30 ml of 1 mol / l hydrochloric acid ethanol solution was poured into a Teflon (registered trademark) centrifuge tube, sealed, and left for 5 days. The mixture was allowed to stand and filtered, and the white precipitate was dried in a dryer at 50 ° C. for 1 day.

  FIG. 3 shows an X-ray diffraction measurement of the sample after adsorption of proton type isallite, 4,4′-bis (triethoxysilyl) biphenyl, and standing in hydrochloric acid ethanol solution. The peak at 2θ = 11.9 ° seen in the X-ray diffraction pattern of proton type isallite is a peak corresponding to the interlayer distance. The d value was 0.74 nm. The XRD pattern of the sample after 4,4′-bis (triethoxysilyl) biphenyl adsorption was 2θ = 4.10 ° (d value = 2.15 nm), 8.13 ° (1.09 nm), 12.4. A peak at 0 (0.71 nm) was observed. This is the peak of the bottom reflection (2θ = 4.10 °) and its higher-order reflection (2θ = 8.13 °, 12.4 °) observed when X-rays are radiated to a substance having a layered structure. is there. It is considered that the interlaminar distance was increased by intercalating hexylamine and 4,4'-bis (triethoxysilyl) biphenyl between proton-exchanged Ilarite layers. Assuming that hexylamine has a molecular length of 0.76 nm and is adsorbed as a bilayer between layers of isallite, since the thickness of one layer of isallite is 0.74 nm, the distance between layers is 2.26 nm. It is estimated. This value almost coincides with the interlayer distance obtained from the X-ray diffraction pattern. In the interlayer of the obtained compound, 4,4′-bis (tri (a)) is present in the amine intercalated as a bimolecular film. It is believed that ethoxysilyl) biphenyl is further intercalated.

  Furthermore, peaks of 2θ = 4.64 ° (d value = 1.90 nm) and 9.36 ° (0.94 nm) were observed in the peak of the XRD pattern after standing in ethanol ethanol. These peaks are also peaks of bottom reflection and higher-order reflection derived from the layered structure, indicating that the layered structure is maintained even after washing with hydrochloric acid ethanol. The interlayer distance was 1.90 nm, which was slightly smaller than before washing with hydrochloric acid ethanol. Assuming that 4,4′-bis (triethoxysilyl) biphenyl has a long molecular length of 1.2 nm and is assumed to be cross-linked perpendicular to the layer of isallite, 4,4′- The interlayer distance of the layered compound in which bis (triethoxysilyl) biphenyl is crosslinked is expected to be 1.94 nm. This value almost coincides with the interlayer distance of 1.90 nm obtained from the X-ray diffraction pattern.

The ²⁹ Si solid state NMR spectrum measured by the magic angle spinning method (MAS method) is shown in FIG. Peaks derived from the T ² and T ³ site structures were observed at −68 ppm and −76 ppm in the spectrum. T ² and T ³ site structures are local structures represented by (—Si—O—) ₂ (HO—) Si (—C—) and (—Si—O—) ₃ Si (—C—), respectively. Corresponding to These peaks are peaks derived from Si atoms in 4,4′-bis (triethoxysilyl) biphenyl, and three ethoxy groups present at both ends of the 4,4′-bis (triethoxysilyl) biphenyl moiety, respectively. Of these, two or three have undergone a hydrolysis reaction and then polymerized with adjacent hydroxyl groups. In addition, peaks derived from the Q ³ and Q ⁴ site structures were observed at −100 ppm and −111 ppm in the spectrum. These site structures correspond to the local structures represented by (—Si—O) ₃ Si—OH and (—Si—O—) ₄ Si, respectively, and are contained in the unit layer of isallite. When the integration ratio of these peaks was calculated, Q ³ / Q ⁴ = 0.5. Since the Q ³ / Q ⁴ ratio of the proton type isyllite as the starting material was Q ³ / Q ⁴ = 1, it was found that the local structure of the Q ³ type was reduced by the reaction. The decrease in Q ³ site is considered to be due to the decrease in hydroxyl groups in Ilarite due to polymerization bonding with adjacent hydroxyl groups. From the results of the observation of T ² and T ³ sites and the decrease of the Q ³ site, it is considered that the biphenyl compound is polymerized with Iralite in a structure as shown in the schematic diagram (FIG. 5). From the above, it was found that Ilarite crosslinked with a biphenyl compound was synthesized.

The nitrogen adsorption / desorption isotherm of the obtained compound is shown in FIG. In the adsorption isotherm, a large increase in the amount of nitrogen adsorption is observed at a low relative pressure (0.05 or less). This is the shape of an adsorption isotherm found in a porous body having a large number of micropores (pore diameter of 1 nm or less) (usually referred to as a type I isotherm). This is presumably because the space occupied by the hexylamine between the layers remained as voids after the hexylamine was removed. The micropore volume was 0.3 ml / g and the BET specific surface area was 616 m ² / g. The BET specific surface area of the proton type Ilarite was 26 m ² / g, which was greatly increased by the cross-linking of the biphenyl compound. From the above, it was found that a porous layered crosslinked product obtained by crosslinking a biphenyl compound was produced.

  The visible ultraviolet absorption spectrum of the obtained compound is shown in FIG. A spectrum having an absorption peak at 280 nm was observed. This is due to the absorption of the biphenyl compound. Further, when the compound was irradiated with this absorption wavelength (280 nm) as excitation light and the fluorescence emission was measured, an emission spectrum having a peak at 340 nm was measured (FIG. 6). This fluorescence spectrum is considered to be a peak derived from excimer emission of the biphenyl compound. Excimer emission is a phenomenon in which a photoexcited compound forms a complex with a nearby compound (within 1 nm) and then emits excitation energy as light, indicating that biphenyl compounds are present in close proximity. From this result, it was suggested that the biphenyl compound in the layer cross-linked the layer with an interval of about 1 nm.

Finally, the obtained compound was dried at 150 ° C. under reduced pressure for 3 hours, then dispersed in a paranitroaniline-ethanol saturated solution and stirred for 3 days. After stirring, the solution was removed by centrifugation and dried. Thereafter, nitrogen gas adsorption measurement was performed. The BET specific surface area obtained from the measurement was 4 m ² / g. The BET specific surface area was greatly reduced from that before stirring, indicating that paranitroaniline was adsorbed on the micropores. The X-ray-diffraction pattern of the compound after paranitroaniline adsorption | suction is shown. The peak position of bottom reflection corresponding to the interlayer distance hardly changed. This indicates that expansion between layers caused by adsorption of paranitroaniline to the micropores is suppressed. Therefore, the reason why the expansion between layers is suppressed is considered that the biphenyl compound crosslinks the layers.

  Under the same conditions as in Example 1, 4,4'-bis (triethoxysilyl) biphenyl was adsorbed on proton-exchanged isallite, and 30 ml of 1 mol / l hydrochloric acid aqueous solution was injected into a Teflon (registered trademark) centrifuge tube. And sealed. After 5 days, it was filtered and dried in a 50 ° C. dryer for 1 day.

The obtained compound had a layered structure with an interlayer distance of 1.86 nm. The micropore volume was 0.2 ml / g, the specific surface area was 478 m ² / g, and it was found that a porous body in which a biphenyl compound was crosslinked was produced.

1. Synthesis of 4,4'-bis (dimethylethoxysilyl) biphenyl
Under the same conditions as the synthesis of 4,4'-bis (triethoxysilyl) biphenyl, dimethyldiethoxysilane was used in place of tetraethylorthosilicate to obtain 4,4'-bis (dimethylethoxysilyl) biphenyl. .

2. Synthesis of Ilarite Crosslinked by Biphenyl Compound Under the same conditions as in Example 1, 4,4'-bis (dimethylethoxysilyl) biphenyl was intercalated into proton exchanged Ilarite previously expanded with hexylamine. did. Further, hexylamine was removed by washing with a 1 mol / l hydrochloric acid aqueous solution. A white solid was obtained after drying.

The X-ray diffraction pattern of the obtained compound showed the same pattern as that obtained in Example 1. The interlayer distance was 1.71 nm. Further, when the nitrogen gas adsorption isotherm was measured, it was an I-type isotherm having micropores. The specific surface area was 50 m ² / g, and it was found that a porous body in which the biphenyl compound was crosslinked was produced.

1. Synthesis of 4,4′-bis (triethoxysilyl) terphenyl 2 g of dichlorotaphenyl and 65 ml of diethyl ether were stirred in a dry ice-ethanol bath in an argon atmosphere. Further, 11.4 ml of tert-butyllithium-hexane solution was added dropwise and stirred for 4 hours. Thereafter, 2 g of chlorotriethoxysilane dissolved in 5 ml of diethyl was added dropwise and stirred for 30 minutes. After stirring, the mixture was returned to room temperature and filtered. After filtration, the solvent was removed by an evaporator. Furthermore, the solid obtained by removing the solvent was purified by chromatography to give a white solid.

2. Synthesis of Ilarite crosslinked by terphenyl compounds
0.3 g of 4,4′-bis (triethoxysilyl) terphenyl was dissolved in 9 ml of a hexane-methylene chloride mixed solvent.

  200 mg of proton-exchanged Ilarite was placed in a centrifuge tube made of Teflon (registered trademark), 1.6 ml of octylamine was added, sealed, and left for 2 days. Two days later, a solution in which 0.3 g of 4,4′-bis (triethoxysilyl) terphenyl was dissolved in 9 ml of a hexane-methylene chloride mixed solvent was prepared, poured into a Teflon (registered trademark) centrifuge tube, and 300 rpm The mixture was stirred at a stirring speed of 7 days. After stirring, the solution was removed and dried at room temperature for 5 days. After drying, 30 ml of 1 mol / l hydrochloric acid aqueous solution was poured into a Teflon (registered trademark) centrifuge tube, sealed, and left for 5 days. The mixture was allowed to stand and filtered, and the white precipitate was dried in a dryer at 50 ° C. for 1 day.

The X-ray diffraction pattern of the obtained compound showed the same pattern as in Examples 1 and 3. The interlayer distance was 1.56 nm. Further, when the nitrogen gas adsorption isotherm was measured, it was an I-type isotherm having micropores. The specific surface area was 27 m ² / g, and it was found that a porous body in which the ter-phenyl compound was crosslinked was produced.

FIG. 1 is a schematic diagram of an aromatic cation-inorganic layered compound porous body according to the prior art. FIG. 2 is a schematic view of the method for producing an aromatic compound-layered inorganic compound porous body of the present invention. FIG. 3 shows an X-ray diffraction pattern. (A) is proton exchange type Ilarite, (B) is X-ray diffraction data after 4 ′, 4′-bis (triethoxysilyl) biphenyl intercalation, (C) is X-ray diffraction data after standing in ethanol ethanol. is there. FIG. 4 shows a ²⁹ Si solid state NMR spectrum measured by magic angle spinning method (MAS method). Peaks of T ² site and T ³ site are observed at −68 ppm and −76 ppm of the spectrum. The Q ³ and Q ⁴ sites observed at −100 ppm and −111 ppm of the spectrum represent the peripheral structure of (—O—Si—O—) ₃ Si (—OH) and (—O—Si—O—) ₄ Si. This is a peak peculiar to Si atoms, and is derived from Si atoms contained in the unit layer of Ilarite. Fig. 5 shows that, by treatment with ethanol hydrochloride, the ethoxy group in 4,4'-bis (triethoxysilyl) biphenyl is hydrolyzed into hydroxyl groups, and two of these hydroxyl groups are present on the surface of the isallite. Schematic diagram showing dehydration condensation with hydroxyl groups and hydrolyzed 4,4'-bis (triethoxysilyl) biphenyls dehydrating and condensing with hydroxyl groups present on the surface of isallite FIG. FIG. 6 is a nitrogen adsorption / desorption isotherm. (A) is a proton exchanged illite, and (B) is a sample after standing in ethanolic hydrochloric acid. FIG. 7 shows a visible ultraviolet absorption spectrum (dotted line) and a fluorescence spectrum (solid line).

Claims (4)

An aromatic compound-layered inorganic compound porous body in which an aromatic compound residue is fixed between layers of a layered inorganic compound via two crosslinking sites, the porous body having a crosslinking site containing a silicon atom, And the said porous body is the following formula | equation (1)

(In the formula, A ¹ and A ² are any unit layers selected from the group consisting of the layered inorganic compound Ilarite, Kanemite, and Magadiite (A ¹ and A ² may be different from each other). And may be the same),
The aromatic compound residue R ³ is a phenylene group, a biphenylene group or a terphenylene group,
In two cross-linking sites represented by —O—Si (Z ¹ ) ₂ — or —O—Si (Z ² ) ₂ —, Z ¹ is R ¹ , OR ² or OA ¹ , and Z ² is R ¹ , OR ² or OA ² (where R ¹ is hydrogen, an alkyl group, an alkenyl group, an aminopropyl group, a mercaptopropyl group, a glycidyloxypropyl group, a mercapto group or a sulfide group, and R ² is A hydrogen, an alkyl group, an alkenyl group, an aminopropyl group, a mercaptopropyl group, a glycidyloxypropyl group, a mercapto group or a sulfide group, and A ¹ and A ² are as defined above),
The aromatic compound residue R ³ represented by the formula is fixed between the layers of the layered inorganic compound via two cross-linking sites —O—Si (Z ¹ ) ₂ — and —O—Si (Z ² ) ₂ —. An aromatic compound-layered inorganic compound porous body characterized by comprising: The aromatic compound-layered inorganic compound porous body according to claim 1, which has a multimeric structure generated by polymerization of a partial structure represented by the formula (1). An adsorbent comprising the aromatic compound-layered inorganic compound porous body according to claim 1 or 2. A catalyst carrier comprising the aromatic compound-layered inorganic compound porous body according to claim 1 or 2.