JP2009067638A - Method for producing crystalline microporous body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide: a method for producing a crystalline aluminum silicate microporous body having grain diameters of ≤2 μm, by which aluminum can be efficiently introduced under a mild condition, to provide the crystalline microporous body being industrially usable, a crystalline microporous molded article, and to provide a crystalline microporous body which exhibits high performances in applications such as a catalyst. <P>SOLUTION: The method for producing the crystalline aluminum silicate microporous body is characterized by including following processes (1) to (4): (1) a mixing process for preparing an alkaline mixed liquid containing kanemite, an alumina precursor, and at least one kind of crystallization adjusting agent selected from ammonium compounds, phosphonium compounds or amines and agitating the mixed liquid for six hours or over; (2) a neutralization process for neutralizing the mixed liquid obtained in the process (1) so that the pH of the mixed liquid becomes 7.6 to 8.4; (3) a solid-liquid separation process for separating fine particles deposited in the mixed liquid neutralized in the process (2) from the mixed liquid; and (4) a crystallization process for crystallizing the fine particles separated from the liquid by heating them. The crystalline aluminum silicate microporous body is produced by the method. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for producing a crystalline aluminum silicate microporous material, and more particularly, to a method for producing a crystalline aluminum silicate microporous material that can be used as, for example, a catalyst, an adsorbent, or a separation material. The crystalline aluminum silicate microporous material obtained by the method of the present invention can be used as a catalyst corresponding to various applications such as the field of petrochemical industry by supporting various metals thereon, and as such, Used as an adsorbent and removal agent for fluorocarbon refrigerants, sulfur fluoride gas, which is an insulation medium for high-voltage power equipment, and air brake air for vehicles, nitrogen compounds in wastewater, and radioactive substances in radioactive wastewater can do.

  Many crystalline microporous materials exist as natural products, as known as mordenite and ferrierite. In addition, various types of artificial crystalline microporous materials such as zeolite-A, zeolite-X, ZSM-5 (for example, see Patent Document 1) and ZSM-11 (for example, see Patent Document 2) are known. It has been.

  Conventionally, when producing a crystalline microporous body, first, after performing a mixing step of forming an alkaline mixed solution containing a silicon dioxide component, an aluminum oxide component and an organic ammonium compound, the inorganic microporous material is heated by high-pressure heating. A so-called “hydrothermal synthesis method” in which a crystallization step of crystallizing a crystalline microporous material in a material mixture has been employed.

  According to this hydrothermal synthesis method, in the crystallization process, the mixed solution is heated for a long period of several days, sometimes 10 days or more, usually at a high temperature of 70 ° C. to 200 ° C. There is a need. In such a crystallization process over a long time, the growth of the crystalline microporous crystal is remarkable, and there is a problem when a high specific surface area such as a catalyst is required as a physical property.

  In addition, the crystalline microporous material obtained by the hydrothermal synthesis method is in the form of fine particles and may need to be molded in some cases, but generally the fine crystalline crystalline microporous material itself has a caking force. Therefore, there is a problem that the performance of the crystalline microporous material is remarkably deteriorated because it must be sintered at an extremely high temperature or molded with a binder interposed.

  As a method for solving such a problem, for example, in Patent Documents 3 to 5, after depositing composite fine particles from an alkaline mixed liquid containing a silicon dioxide component, an aluminum oxide component and an organic ammonium compound, There is disclosed a method for producing a crystalline microporous material, characterized in that crystallization is carried out without direct contact. According to these methods, a crystalline microporous material can be synthesized under milder conditions than conventional hydrothermal synthesis, and therefore, when a high specific surface area such as a catalyst is required as a physical property, crystallization by hydrothermal synthesis is possible. Higher performance than the porous microporous material can be expected.

  By the way, it is known that the aluminum atom in the crystalline microporous material exhibits properties such as an active site of catalytic reaction. General knowledge is explained in Non-Patent Document 1, for example. However, in the methods disclosed in Patent Documents 3 to 5, the method of introducing the aluminum atom has not been sufficiently studied.

  That is, in Patent Document 3, kanemite is used as a silicon dioxide component, and aluminum is introduced into the crystalline microporous body by aluminum chloride. However, since aluminum chloride causes a severe hydrolysis reaction in an aqueous solution, There is a problem from the viewpoint of controlling the reaction of introducing aluminum into the porous microporous material.

  In Patent Document 4, amorphous silicon dioxide such as water glass and tetraethylorthosilicate (TEOS) is used as a silicon dioxide component, and aluminum is introduced into aluminum such as sodium aluminate and aluminum tri-sec-butoxide. Although it is made of a compound, the above-mentioned water glass, TEOS, etc., which are silicon dioxide components, are amorphous components, and elements other than silicon dioxide components (Na and ethoxy) are present in an indefinite ratio, so crystalline microporous These non-stoichiometric elements become an obstructive factor at the time of conversion to a body, particularly at the time of Si—OH group condensation. Similarly, sodium aluminate and alkoxide used for introducing aluminum are also affected by non-stoichiometric elements and anions, and there is a problem that it is difficult to control the reaction of introducing aluminum into the crystalline microporous body.

  Furthermore, in Patent Document 5, aluminum is introduced into a crystalline microporous body using sodium aluminate, ion exchange is performed using ammonium nitrate, and then water and ammonia are removed by calcination to introduce aluminum. A method for obtaining a porous body is disclosed. However, in this method, since the raw material slurry before ion exchange shows strong alkalinity, a large amount of ammonium nitrate must be used. This becomes a problem by producing significant volume shrinkage in the production of a microporous body.

  Furthermore, it is known about various reactions that a small particle size zeolite is preferable in a crystalline microporous material. For example, in Patent Document 6, a zeolite having a particle size of 2 μm or less is suitable for catalytic cracking of hydrocarbons. It is disclosed to be used.

  Therefore, it is easy to control the introduction reaction of aluminum into the crystalline microporous body under mild conditions, and aluminum can be introduced efficiently, the particle size is small, and the crystalline aluminum silicate has a high function. A method for obtaining a microporous material has been demanded.

Japanese Patent Publication No.46-10064 Japanese Patent Publication No. 53-23280 JP-A-8-319112 Japanese Laid-Open Patent Publication No. 9-40417 International Publication No. WO01 / 19731 JP-A-4-3527331 "Zeolite Science and Engineering", Yoshio Ono, T. Akishima, Kodansha Scientific, (2000)

  From the viewpoint of enhancing the functionality of the crystalline microporous material, the crystalline microporous material can be synthesized by a production method that does not rely on the hydrothermal synthesis method, and aluminum atoms can be efficiently introduced into the porous material. Developing a method for producing crystalline aluminum silicate microporous material is a very important issue.

  This invention solves said subject and provides the manufacturing method of the crystalline aluminum silicate microporous body with a particle diameter of 2 micrometers or less which can introduce | transduce aluminum efficiently on mild conditions. Is.

  In order to solve this problem, the inventors have studied the raw materials used, the process, the treatment conditions, and the like in detail in the method for producing a crystalline aluminum silicate microporous body, and as a result, have reached the present invention.

That is, the present invention includes the following steps (1) to (4).
(1) Mixing step of preparing an alkaline mixed solution comprising at least one crystallization regulator selected from kanemite, alumina precursor and ammonium compound, phosphonium compound or amines, and stirring for 6 hours or more (2) step Neutralization step for neutralizing the pH of the mixed solution obtained in (1) to 7.6 to 8.4 (3) Mixing fine particles precipitated in the mixed solution neutralized in step (2) Solid-liquid separation step of separating from liquid (4) A method for producing a crystalline aluminum silicate microporous material, comprising a crystallization step of heating and crystallizing solid-liquid separated fine particles.

  The present invention also provides a crystalline aluminum silicate microporous material produced by this production method.

  According to the present invention, it is possible to produce a crystalline microporous material having a much smaller particle diameter than that of the hydrothermal synthesis method, and to produce a crystalline aluminum silicate microporous material having a high specific surface area by efficiently introducing aluminum. Obtainable.

  The method of the present invention includes (1) mixing step, (2) neutralization step, (3) solid-liquid separation step, and (4) crystallization step.

  First, in the mixing step (1), a kanemite component, an alumina precursor, and a crystallization modifier, which are raw materials for the crystalline aluminum silicate microporous material, are coexisted under alkaline conditions and sufficiently homogenized.

Kanemite used in the present invention is a layered silicate compound whose ideal composition formula is represented by NaHSi ₂ O ₅ . This is preferably dried and pulverized from the viewpoint of efficient mixing with the alumina precursor. When a kanemite component and a crystallization adjusting agent, for example, an ammonium compound are allowed to coexist under alkaline conditions, ammonium ions of the ammonium compound are inserted between the layers of the kanemite to form an ammonium salt of kanemite. This is because sodium ions originally located between the layers of kanemite are replaced with ammonium ions (cation ion exchange). Theoretically, the sodium ions and ammonium ions between the layers are exchanged by 1: 1. . This process is observed, for example, by powder X-ray diffraction, as an increase in interlayer distance and a decrease in structural regularity (decrease in diffraction intensity) due to condensation of Si—OH groups present between the layers.

  Although the details of the process in which the alumina precursor is mixed with the kanemite ammonium compound are not clear, the mixture exhibits alkalinity. It is conceivable that silicon in the silicate skeleton is replaced with aluminum.

  In this specification, an alumina precursor means a compound derived from alumina by firing. Examples of the alumina precursor include aluminum salts, aluminum alkoxides, and alumina hydrates. The alumina precursor used in the present invention is preferably neutral in water from the viewpoint of smoothly proceeding hydrolysis under alkaline conditions, and further contains other metal ions and anions that become an inhibiting factor in the condensation reaction. Those not present are more preferred. From such a viewpoint, an alumina hydrate can be suitably used as the alumina precursor.

Alumina hydrate can be represented by the general formula Al ₂ O ₃ .nH ₂ O, including aluminum hydroxide. Examples of the alumina hydrate include crystalline alumina hydrate such as gibbsite, boehmite, pseudoboehmite, bayerite, norstrandide, and diaspore, and amorphous alumina hydrate. An alumina sol in which alumina hydrate is suspended and dispersed in water in a colloidal form can also be used. The alumina sol can be obtained by adding a base such as ammonia to an aqueous solution of a water-soluble aluminum salt. It can also be obtained by hydrolyzing an organic compound such as aluminate or aluminum alkoxide, or by solting boehmite or pseudoboehmite in the acidic region. In the present invention, alumina sol and boehmite can be particularly preferably used.

  In the present invention, various ammonium compounds, phosphonium compounds, and amines can be used as the crystallization regulator, as long as it contains at least one selected from these, but from the viewpoint of versatility, the ammonium compound Is preferably used.

Examples of ammonium compounds used as crystallization modifiers include those of formula (i)
(R ₁ ) ₄ N ⁺ (i)
(Wherein R ₁ is the same or different and represents a group selected from a hydrogen atom, an alkyl group having 10 or less carbon atoms, or an aryl group)
The ammonium compound containing the ammonium ion represented by these is mentioned.

In particular, tetra n-butylammonium ion ((n-C ₄ H ₉ ) ₄ N ⁺ ), tetra n-propylammonium ion ((n-C ₃ H ₇ ) ₄ N ⁺ ), tetraethylammonium ion ((C ₂ H _{5) 4} n ^+), tetramethylammonium ion ^{_{((CH 3) 4 n +}} ), n- propyl trimethyl ammonium ion _{((n-C 3 H 7} ) (CH 3) 3 n +), benzyltrimethylammonium ion ( An ammonium compound having an ammonium ion such as (C ₇ H ₇ ) (CH ₃ ) ₃ N ⁺ ) is preferable.

Examples of phosphonium compounds used as crystallization modifiers include those represented by formula (ii)
(R ₂ ) ₄ P ⁺ (ii)
(Wherein R ₂ is the same or different and represents a group selected from a hydrogen atom, an alkyl group having 10 or less carbon atoms or an aryl group)
The phosphonium compound containing the phosphonium ion represented by these is mentioned.

In particular, it has phosphonium ions such as tetra n-butylphosphonium ion ((n-C ₄ H ₉ ) ₄ P ⁺ ) and benzyltriphenylphosphonium ion ((C ₇ H ₇ ) (C ₆ H ₅ ) ₃ P ⁺ ). Phosphonium compounds are preferred.

Furthermore, examples of the amine include 1,4-dimethyl-1,4-diazobicyclo (2.2.2) octane, pyrrolidine, n-propylamine (n-C ₃ H ₇ NH ₂ ), methylquinuclidine and the like. Can be mentioned.

  If a tetrapropylammonium compound is used as a crystallization modifier, a crystalline microporous body having an MFI structure can be obtained, and if a tetrabutylammonium compound is used, a crystalline microporous body having an MEL structure can be obtained. If the crystallization regulator is appropriately selected depending on the structure to be obtained, crystalline microporous materials having various pore sizes can be obtained.

  The mixing step of the kanemite component, the alumina precursor, and the crystallization modifier may be performed at room temperature or under heating. Moreover, the time for performing the mixing step is 6 hours or longer, more preferably 9 hours or longer at room temperature. If the mixing time is less than 6 hours, the substitution of silicon and aluminum in the silicate skeleton becomes insufficient, which is not preferable.

  Subsequently, the mixture after performing a mixing process is neutralized by the neutralization process of (2) of this invention. Since the mixture exhibits alkalinity, an aqueous acid solution can be used for neutralization. The ammonium compound of kanemite is precipitated as fine particles by the neutralization step. In addition, sodium ions eluted from kanemite in the mixing step are recovered in the aqueous solution. The neutralization step may be performed at room temperature, or may be performed under heating for process promotion. The purpose of the neutralization step is to remove sodium ions in addition to precipitating the ammonium compound of kanemite by neutralization. Therefore, when adding an aqueous acid solution, an acid that can be estimated from the raw kanemite is added. Is preferred. The acid aqueous solution used is preferably a strong acid such as hydrochloric acid and can be easily removed from the fine particles after the solid-liquid separation step.

  In this neutralization step, the pH of the mixed solution is preferably about 7.6 to 8.4, particularly about 8. When the pH is higher than 8.4, sodium is not sufficiently removed, and the amount of precipitated fine particles is reduced. If the pH is lower than 7.6, ammonium of kanemite, which is the main component of the fine particles, is subject to hydrolysis, which may lead to a decrease in the yield of the finally obtained crystalline aluminum silicate microporous material. is there.

  Furthermore, the fine particles precipitated from the mixed solution that has undergone the neutralization step are separated by the solid-liquid separation step (3) of the present invention. In this separation, the liquid mixture may be allowed to stand, or solid-liquid separation may be promoted by a centrifuge. The fine particles separated by the solid-liquid separation step can adjust the water content by drying. The fine particles separated in the solid-liquid separation step may be washed and then dried. Furthermore, since the fine particles are much easier to mold than the crystalline microporous material, the fine particles obtained in this step are formed by a simple operation such as pressurization, and the subsequent crystal A chemical conversion step may be performed.

  Thereafter, in the crystallization step (4), the fine particles separated in the solid-liquid separation step are crystallized under heating. This crystallization step can be performed by sealing the fine particles or a molded body obtained by molding the fine particles in a sealed container and then heating the sealed container without bringing the fine particles into contact with liquid water. Further, this crystallization step may be performed while supplying water vapor.

  The crystallization process of the present invention proceeds under milder conditions as compared with hydrothermal synthesis. The crystallization reaction temperature is preferably 100 ° C. to 200 ° C. The higher the crystallization temperature, the faster the crystallization speed, and the crystallization can be performed in a short time. For example, at a reaction temperature of 130 ° C., the time required for the crystallization step is about 24 hours.

  The crystalline aluminum silicate microporous material obtained through the above crystallization step may be used as it is depending on the application, or may be further used for the application through a firing step. The conditions for firing are appropriately selected depending on the intended use of the crystalline microporous material and the crystal structure, but the general firing conditions are a temperature of 400 ° C. to 600 ° C., a firing time of 5 hours to 48 hours. Degree.

  According to the method of the present invention described above, a crystalline microporous material can be synthesized under mild conditions, and aluminum atoms can be efficiently introduced into the porous material. The aluminum atom in the crystalline aluminum silicate microporous material can be measured by solid-state NMR. In particular, regarding crystalline aluminum silicate microporous material, ZSM-5, which is often used as a catalyst, can be confirmed by a peak derived from 4-coordinated aluminum in the vicinity of 50 ppm.

  Further, according to the method of the present invention, a crystalline aluminum silicate microporous body having a much smaller particle diameter and a high specific surface area can be easily obtained as compared with that obtained by the hydrothermal synthesis method. The particle diameter of the crystalline aluminum silicate microporous material obtained by the method of the present invention is preferably 2 μm or less, and more preferably 1 μm or less.

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. In addition, as a raw material, the following composition (all the things of% display were weight%) was used.
○ Pre-feed (δ-Na ₂ Si ₂ O ₅ ) (manufactured by Tokuyama Siltech Co., Ltd.)
○ Cataloid SI-30: SiO ₂ : 30.5%, Na ₂ O: 0.5% (manufactured by Catalytic Chemicals Co., Ltd.)
○ Boehmite: Analytical value Al ₂ O ₃ : 74.44%
○ Aluminum nitrate nonahydrate (manufactured by Wako Pure Chemical Industries, Ltd.)
○ Tetrapropylammonium hydroxide: 20-25% aqueous solution (manufactured by Tokyo Chemical Industry Co., Ltd.)
○ Sodium hydroxide (manufactured by Wako Pure Chemical Industries, Ltd.)

Example 1
800 mL of deionized water was prepared in a 1 L beaker, 40 g of pre-feed was added thereto, and the mixture was allowed to stand at room temperature for 9 hours to immerse water. The resulting precipitate was collected by vacuum filtration and naturally dried at room temperature to obtain 19.3 g of kanemite fine particles (ideal composition formula: NaHSi ₂ O ₅ .3H ₂ O).

In a 200 mL beaker, 6.25 g of the kanemite and 0.20 g of boehmite were dispersed in 60 mL of deionized water. Thereto, tetrapropylammonium hydroxide _{((n-C 3 H 7} ) 4 NOH) 52.5mL and the mixture was stirred for 9 hours at room temperature (mixing step). Thereafter, 6 mol / L hydrochloric acid was added and the pH was gradually lowered to about 8. As a result, the volume of kanemite rapidly swollen (neutralization step). This phenomenon is considered to be due to the ion exchange of sodium ions in the kanemite with tetrapropylammonium ions ((n-C ₃ H ₇ ) ₄ N ⁺ ).

The swollen kanemite was washed with 300 mL of deionized water while filtering under reduced pressure and collected, and then dried at 35 ° C. for 3 days to obtain a white powder (solid-liquid separation step). The white powder is considered to have become a complex between kanemite alumina precursor and tetrapropylammonium ion _{((n-C 3 H 7} ) 4 N +).

  About 4 g of the composite is placed on a small glass filter, and the glass filter is placed in a heat-resistant container coated with fluorine resin together with about 4 mL of deionized water so that the composite does not directly contact water. As described above, a heat treatment was performed by exposing to 130 ° C. water vapor for 24 hours to obtain a reaction product (crystallization step).

  The reaction product was thoroughly washed with deionized water and dried at 60 ° C. for 12 hours to obtain a white powder. When this white powder was examined by measuring a powder X-ray diffraction spectrum, it was found to be a crystalline microporous material composed of ZSM-5 having an MFI structure. Further, when NMR of aluminum was measured, a peak derived from tetracoordinated aluminum was observed in the vicinity of 50 ppm, and it was confirmed that aluminum atoms were incorporated into the ZSM-5 skeleton. Moreover, when the shape of ZSM-5 synthesized by SEM was confirmed, ZSM-5 particles having a particle diameter of 0.1 to 0.2 μm could be observed uniformly.

Example 2
In Example 1, the mixing process at room temperature for 9 hours was changed to 6 hours at room temperature, and the others were performed under the same conditions as in Example 1. When the obtained white powder was examined by measuring a powder X-ray diffraction spectrum, it was found to be a crystalline microporous material composed of ZSM-5 having an MFI structure. Further, when NMR of aluminum was measured, a peak derived from tetracoordinated aluminum was observed in the vicinity of 50 ppm, and it was confirmed that aluminum atoms were incorporated into the ZSM-5 skeleton. Moreover, when the shape of ZSM-5 synthesized by SEM was confirmed, ZSM-5 particles having a particle diameter of 0.1 to 0.2 μm could be observed uniformly.

Comparative Example 1
11.3 g of the pre-feed was immersed in 110 mL of deionized water for 3 hours at room temperature in a 300 mL beaker to obtain a slurry solution. Without solid-liquid separation from the slurry solution, 0.42 g of boehmite and 112 mL of tetrapropylammonium hydroxide were added and stirred only at room temperature for 3 hours (mixing step). Thereafter, 6 mol / L hydrochloric acid was added and the pH was gradually lowered to about 8. As a result, the volume of kanemite rapidly swollen (neutralization step).

  The swollen kanemite was washed and recovered with 600 mL of deionized water while filtering under reduced pressure, and then dried at 35 ° C. for 3 days to obtain a white powder (solid-liquid separation step). About 4 g of the white powder is placed on a small glass filter, and this glass filter is put in a heat-resistant container coated with fluorine resin together with about 4 mL of deionized water, so that the white powder does not come into direct contact with water. Thus, the heat treatment which exposed to 130 degreeC water vapor | steam for 24 hours was performed, and the reaction product was obtained (crystallization process). The reaction product was thoroughly washed with deionized water and dried at 60 ° C. for 12 hours to obtain a white powder.

  When this white powder was examined by measuring a powder X-ray diffraction spectrum, it was found to be a crystalline microporous material composed of ZSM-5 having an MFI structure. However, when NMR of aluminum was measured, a peak derived from tetracoordinated aluminum in the vicinity of 50 ppm could not be observed. In addition, when the shape of the zeolite synthesized by SEM was confirmed, ZSM-5 particles having a particle diameter of 0.1 to 0.2 μm could be observed uniformly.

Comparative Example 2
ZSM-5 was synthesized by an ordinary hydrothermal synthesis method using sodium hydroxide, aluminum nitrate nonahydrate, and cataloid SI-30. At this time, the average particle diameter by SEM observation was 9 μm. Further, when NMR of aluminum was measured, a peak derived from tetracoordinated aluminum was observed in the vicinity of 50 ppm, and it was confirmed that aluminum atoms were incorporated into the ZSM-5 skeleton.

Claims (15)

Next steps (1) to (4)
(1) Mixing step of preparing an alkaline mixed solution comprising at least one crystallization regulator selected from kanemite, alumina precursor and ammonium compound, phosphonium compound or amines, and stirring for 6 hours or more (2) step Neutralization step for neutralizing the pH of the mixed solution obtained in (1) to 7.6 to 8.4 (3) Mixing fine particles deposited in the mixed solution neutralized in step (2) Solid-liquid separation step of separating from liquid (4) A method for producing a crystalline aluminum silicate microporous material, comprising a crystallization step of heating and crystallizing solid-liquid separated fine particles.   The method for producing a crystalline aluminum silicate microporous material according to claim 1, wherein the kanemite is fine particles dried and crushed.   The method for producing a crystalline aluminum silicate microporous material according to claim 1 or 2, wherein the alumina precursor exhibits neutrality when contacted with water.   The method for producing a crystalline aluminum silicate microporous material according to any one of claims 1 to 3, wherein the alumina precursor is an alumina hydrate.   The method for producing a crystalline aluminum silicate microporous material according to any one of claims 1 to 4, wherein the alumina precursor is alumina sol or boehmite. The crystallization modifier is represented by the following formula (i)
(R ₁ ) ₄ N ⁺ (i)
(Wherein R ₁ is the same or different and represents a group selected from a hydrogen atom, an alkyl group having 10 or less carbon atoms, or an aryl group)
The method for producing a crystalline aluminum silicate microporous material according to any one of claims 1 to 5, wherein the ammonium compound contains an ammonium ion represented by the formula:   The crystallization modifier is an ammonium compound containing an ammonium ion selected from tetra n-butyl ammonium ion, tetra n-propyl ammonium ion, tetraethyl ammonium ion, tetramethyl ammonium ion, n-propyl trimethyl ammonium ion and benzyl trimethyl ammonium ion. The method for producing a crystalline aluminum silicate microporous material according to any one of claims 1 to 5, which is at least one or more. The crystallization modifier is represented by the following formula (ii)
(R ₂ ) ₄ P ⁺ (ii)
(Wherein R ₂ is the same or different and represents a group selected from a hydrogen atom, an alkyl group having 10 or less carbon atoms or an aryl group)
The method for producing a crystalline aluminum silicate microporous material according to any one of claims 1 to 5, wherein the phosphonium compound contains a phosphonium ion represented by the formula:   6. The crystalline silicic acid according to claim 1, wherein the crystallization modifier is at least one or more of phosphonium compounds containing a phosphonium ion selected from tetra n-butylphosphonium ion and benzyltriphenylphosphonium ion. A method for producing an aluminum microporous body.   The crystallization modifier is at least one or more amines selected from 1,4-dimethyl-1,4-diazobicyclo (2.2.2) octane, pyrrolidine, n-propylamine and methylquinuclidine. The method for producing a crystalline aluminum silicate microporous material according to any one of claims 1 to 5.   The method for producing a crystalline aluminum silicate microporous material according to any one of claims 1 to 10, wherein the fine particles obtained by the solid-liquid separation step are washed with water, dried and then subjected to a crystallization step.   The method for producing a crystalline aluminum silicate microporous material according to any one of claims 1 to 11, wherein the crystallization step is performed after molding the fine particles obtained by the solid-liquid separation step.   13. The crystallization process is performed according to any one of claims 1 to 12, wherein after the fine particles obtained by the solid-liquid separation step are sealed in a sealed container, the sealed container is heated without bringing the fine particles into contact with liquid water. A method for producing a crystalline aluminum silicate microporous material.   The method for producing a crystalline aluminum silicate microporous material according to any one of claims 1 to 13, wherein a crystallization step is performed using water vapor on the fine particles obtained by the solid-liquid separation step. A crystalline aluminum silicate microporous material produced by the production method according to claim 1.