KR20200101758A - Synthesis method of layered silicate and layered silicate synthesized by the same - Google Patents

Abstract

According to the present invention, a method for synthesizing a layered silicate is performed by synthesizing a layered silicate with spherical silica particles having an average particle diameter of 20 μm or more as a silica source, so as to provide a layered silicate with a core-shell shape, in which a core is porous and an external shell has a layered structure and the inside is porous and an external surface has a closed structure, and thus can be used in various application fields such as microreactors, drug delivery materials, etc. In addition, the layered silicate synthesis method according to the present invention synthesizes the layered silicate by using spherical silica particles having an average particle diameter of 20 μm or more as a silica source, thereby shortening a hydrothermal synthesis time and improving the efficiency of the synthesis process.

Description

Synthesis method of layered silicate and layered silicate synthesized by the same}

The present invention relates to a method for synthesizing a layered silicate comprising a porous core and a shell having a layered structure, and to a layered silicate synthesized therefrom.

Layered silicates such as magadite or kenyite, which are representative crystalline layered compounds, are compounds showing a crystalline structure composed of pure silicon dioxide (SiO ₂ ), unlike most natural clay minerals composed of aluminosilicate. Since it was first discovered in mid-year, silicon dioxide has been artificially synthesized and used by hydrothermal reaction in an alkaline atmosphere.

Among the layered silicates, magadite and kenyite, which are easy to disperse in each layer, are representative. Of these, magadite is a SiO ₄ tetrahedron as a basic unit. Layers are formed, and they are stacked to form an independent individual plate, and these plate-like structures form a bundle like a rose flower. Kenyite looks the same as magadite, except that SiO ₄ tetrahedral sheets are superimposed to form a thicker layer than magadite.

Layered silicates such as magadite or kenyite have excellent cation exchange capacity of about 130 to 180 meq/100 g, have excellent thermal stability and chemical resistance, and have a finely separated plate structure. Or, it has properties that are distinct from synthetic clay. In other words, most natural or synthetic clay minerals consist of a layered structure, but individual layers, such as magadite or kenyite, are not in a form that can be separated and scattered in a very regular and elaborate manner. In most cases, it is difficult to clearly determine the presence or absence of a layered structure in terms of appearance because of its shape.

Recently, as the excellent physical properties of clay-polymer nanocomposites are known, new lighting for these clay minerals is being made. Therefore, it has been found that it has several possibilities to optimally improve the physical properties of the nanocomposite.

However, in spite of the structural characteristics of layered silicates such as magadite or kenyite, development of a method for economically producing them and techniques for use of the layered silicates is insignificant.

In addition, conventionally known method for synthesizing layered silicate is that it is usually manufactured in a flower-like shape, but it is difficult to control the shape of the structure of layered silicate, so that the shape of the structure cannot be changed for the intended use. There is a disadvantage in that the application field is somewhat narrow, and in addition, there is a problem that the hydrothermal synthesis time required to synthesize the layered silicate takes a long time. In relation, Korean Patent Laid-Open No. 1992-7002852 describes the synthesis of a Kenite-type layered silicate material, but it takes a relatively long time to proceed with the hydrothermal synthesis reaction, and also, the shape of the layered silicate structure is determined. I can't control it.

Accordingly, in order to expand the industrial application field of the layered silicate, research on a synthesis method capable of controlling the shape of the structure and improving the efficiency of the process is urgently needed.

KR1992-7002852A

The present invention has been devised to solve the problems of the prior art, and provides a method for synthesizing a core-shell type layered silicate including a porous core and a shell composed of a layered structure.

Another object of the present invention is to provide a method for synthesizing a layered silicate in which the efficiency of the process is improved by shortening the hydrothermal synthesis time during the synthesis of the layered silicate.

Another object of the present invention is to provide a layered silicate in the form of a core-shell, including a shell made of a porous core and a layered structure, manufactured by the above manufacturing method.

In order to solve the above problems, the present invention comprises the steps of 1) forming a reactant solution by mixing a silica source, a basic substance, and water; And 2) hydrothermal synthesis of the reactant solution to form a layered silicate, wherein the silica source is a spherical silica particle having an average particle diameter (D50) of 20 µm or more.

In addition, the present invention is a porous core; And a shell made of a layered structure, wherein the core and the shell are made of silica.

The layered silicate synthesis method according to the present invention synthesizes the layered silicate using spherical silica particles having an average particle diameter of 20 µm or more as a silica source, so that the core exhibits porosity and the outer shell has a layered structure in a core-shell form. Silicates can be synthesized.

In addition, the layered silicate of the present invention has a closed structure consisting of a layered structure having a high density on the inside and a closed structure, so that the adsorption capacity of the layered silicate can be further improved, and the specific surface area in the layered structure including the porous core Since it can be greatly improved, the adsorption capacity can be greatly increased.

In addition, as the porous silica core is formed in the shell of the layered structure, materials such as polymers, pharmaceuticals, and enzymes that can be intercalated can more easily penetrate, thereby remarkably improving compatibility with materials such as polymers. I can. Due to such properties, the application range of the layered silicate of the present invention can be very broad, and for example, it can be used in various applications such as reinforcing agents for polymer resins, fillers for cosmetics, nanocomposites, microreactors, and drug delivery materials.

In addition, the layered silicate synthesis method according to the present invention synthesizes the layered silicate using spherical silica particles having an average particle diameter of 20 μm or more as a silica source, thereby shortening the hydrothermal synthesis time and improving the efficiency of the synthesis process.

1 shows a SEM photograph of the spherical silica particles prepared in Preparation Example 1.
2 shows an SEM photograph of the spherical silica particles prepared in Preparation Example 2.
3 shows a SEM photograph of amorphous silica particles prepared in Comparative Preparation Example 1.
4 and 5 show SEM photographs of the layered silicate prepared in Example 1.
6 shows an SEM photograph of the layered silicate prepared in Example 2.
7 shows an SEM photograph of the layered silicate prepared in Example 3.
8 shows an SEM photograph of the layered silicate prepared in Example 4.
9 shows an SEM photograph of the layered silicate prepared in Example 5.
10 shows a SEM photograph of the layered silicate prepared in Comparative Example 1.
11 shows an SEM photograph of the layered silicate prepared in Comparative Example 2.
12 shows the XRD analysis results of the layered silicate prepared in Example 1.

Hereinafter, the present invention will be described in more detail to aid understanding of the present invention.

The terms or words used in the present specification and claims should not be construed as being limited to their usual or dictionary meanings, and the inventor may appropriately define the concept of terms in order to describe his own invention in the best way. It should be interpreted as a meaning and concept consistent with the technical idea of the present invention based on the principle that there is.

A method for synthesizing a layered silicate according to an embodiment of the present invention includes: 1) forming a reactant solution by mixing a silica source, a basic substance, and water; And 2) hydrothermal synthesis of the reactant solution to form a layered silicate, wherein the silica source is a spherical silica particle having an average particle diameter (D50) of 20 µm or more.

Here, the average particle diameter (D50) may be defined as a particle diameter corresponding to 50% of the cumulative number of particles in the particle diameter distribution curve of the particles. The average particle diameter (D50) may be measured using, for example, a laser diffraction method. In general, the laser diffraction method can measure a particle diameter of about several mm from a submicron region, and high reproducibility and high resolution results can be obtained.

In addition, the layered silicate of the present invention is a silicate crystal made of silicon dioxide, and may include a layered lamella structure. In particular, the layered silicate according to an embodiment of the present invention includes a shell having a layered structure and a porous core. It is a silicate containing structure.

In addition, the layered silicate of the present invention may specifically include magadite or kenite, and more specifically, may include magadite or kenite including a porous core and a layered shell.

Specifically, the silica source according to an embodiment of the present invention may be spherical silica particles, and the silica particles are secondary silica particles (primary silica particles) on the primary particles are aggregated to form a spherical shape. It may be silica particles (secondary silica particles; secondary silica particles) on the particles. In addition, the spherical silica particles can be obtained from a reaction product obtained by reacting a silica material with a neutralizing agent and a gelling agent, and from the reaction product prepared by reacting by optionally further adding a surfactant to promote the generation of spherical silica particles. Can be obtained.

More specifically, the spherical silica particles of the present invention may be prepared by mixing a silica material and an organic solvent to prepare a silica precursor solution, adding a neutralizing agent and a gelling agent, and drying the silica gel prepared by reaction. In addition, a surfactant may be optionally further added to the silica precursor solution, and a phase separation and washing process before drying may be further included.

Here, the silica material may be used without limitation as long as it is capable of forming spherical silica particles. For example, a water glass solution, or tetramethyl orthosilicate (TMOS), tetraethyl orthosilicate (tetraethyl) may be used. Orthosilicate; TEOS) or a silicon-containing alkoxide-based compound such as methyl triethyl orthosilicate may be used, and in the present invention, more specifically, a water glass solution may be used.

Since the water glass in the water glass solution has a relatively low raw material cost among silica materials that can be used in reality, it may have an economic effect in terms of manufacturing cost when using water glass to produce a silica source.

In the present invention, the water glass solution may represent a diluted solution obtained by adding and mixing distilled water to a water glass, and the water glass is sodium silicate, Na ₂ , which is an alkali silicate salt obtained by melting silicon dioxide (SiO ₂ ) and an alkali. SiO ₃ ).

In addition, according to an embodiment of the present invention, the neutralizing agent for neutralizing the silica material may include an acid material, and as an acid that can be used as a neutralizing agent, fluorosilicic acid (H ₂ SiF ₆ ), sulfuric acid (H ₂ SO ₄ ), Inorganic acids including hydrochloric acid (HCl), nitric acid (HNO ₃ ), phosphoric acid (H ₃ PO ₄ ) and hydrofluoric acid (HF), acetic acid (CH ₃ COOH), oxalic acid, maleic acid, horses There may be organic acids including malonic acid, citric acid, and propionic acid, and in consideration of ease of pH control, ease of handling, and safety of the reactant, preferably acetic acid is included. can do.

In addition, the gelling agent according to an embodiment of the present invention may be used without limitation as long as any material capable of gelling a silica precursor into silica gel, specifically isopropanol, sodium hydroxide (NaOH), and potassium hydroxide (KOH). , Calcium hydroxide (Ca(OH) ₂ ), ammonia (NH ₃ ), ammonium hydroxide (NH ₄ OH), tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (TPAH), tetrabutylammonium hydroxide (TBAH), methylamine, ethylamine, isopropylamine, monoisopropylamine, diethylamine, diisopropylamine, dibutylamine, trimethylamine, triethylamine, tri Isopropylamine, tributylamine, choline, monoethanolamine, diethanolamine, 2-aminoethanol, 2-(ethylamino)ethanol, 2-(methylamino)ethanol, N-methyl diethanolamine, dimethylaminoethanol, Diethylaminoethanol, nitrilotriethanol, 2-(2-aminoethoxy)ethanol, 1-amino-2-propanol, triethanolamine, monopropanolamine, dibutanolamine, and pyridine can be at least one selected from the group consisting of And, preferably, sodium hydroxide, ammonium hydroxide, potassium hydroxide, isopropanol, or a mixture thereof.

In addition, the spherical silica particles according to an embodiment of the present invention may have an average particle diameter (D50) of 20 μm or more, and specifically, in terms of forming a structure having a desired shape and improving process efficiency, the average particle diameter is It may be 20 to 60 μm, and even more preferably 30 to 55 μm.

In the present invention, as the silica particles on the nano-level primary particles are agglomerated to form spherical silica particles on the secondary particles in the particle diameter range, silica constituting the particles when the hydrothermal synthesis reaction for the layered silicate synthesis is performed. A layered structure of a layered silicate is formed from the surface of the particles due to the crystallization action of the component and the salt component of the basic substance present in the reactant solution, such as a sodium component. In addition, due to a reaction in which silica is dissolved and then reprecipitation, the pores of the core toward the center gradually increase, and the inner core forms a porous silica structure without forming a layered structure. The shell, which is the surface of, surrounds the core and can form a magadite or kenyite layered structure in the form of a flower (FLOWER LIKE).

When amorphous silica particles having an irregular shape other than spherical are used as a silica source, the order of the reaction sites is not determined, and multiple reactions are performed at random, forming a core-shell type layered silicate having a porous core. Can not. In addition, even if spherical silica particles are used, if the particle diameter is less than 20 µm, the particles are too small to form a layered shell on the surface of the particles before forming a layered shell. Most of the silica components constituting the particles are salts of basic substances in the reactant solution. Since the crystallization reaction is performed by direct contact with a component such as a sodium component, the entire silica particle is crystallized only in a layered structure, making it difficult to form a core-shell type particle including both a porous core and a layered shell. In the case of using silica particles of a level, such as colloidal silica particles, the pattern is more evident.

According to an embodiment of the present invention, the reactant solution may be a mixture of a basic substance, a silica source, and water in a molar ratio of 1:1:50 to 1:25:500, specifically 1:1:100 to 1:10:200, more specifically, may be mixed in a molar ratio of 1:3:120 to 1:7:180, and in the above range, a shell having a layered crystal structure of a layered silicate can be more easily produced. have.

In addition, according to an embodiment of the present invention, the basic material may be used without limitation as long as it can form a layered silicate by performing a crystallization reaction with a silica source, and specifically, may include a basic sodium material, More specifically, it may contain one or more selected from the group consisting of sodium hydroxide (NaOH), potassium hydroxide (KOH), sodium carbonate (Na ₂ CO ₃ ) and sodium hydrogen carbonate (NaHCO ₃ ), and more specifically, hydroxide It can be sodium.

In addition, according to an embodiment of the present invention, deionized water may be used as water in the reactant solution.

In addition, according to an embodiment of the present invention, the hydrothermal synthesis in step 2) may be performed at a temperature of 100 to 250 °C for 1 to 50 hours, and if the temperature range is satisfied, it is performed with an optimal process time. As a result, the efficiency of the process can be increased, and the stability of the reaction can be secured because the pressure that can increase as the temperature is high can be controlled. In addition, when the above synthesis time is satisfied, the layered crystal structure and the porous core of the layered silicate can be more easily generated, and the problem of energy waste due to unnecessarily prolonged reaction can be prevented.

Specifically, hydrothermal synthesis may be performed for 5 to 24 hours, more specifically 7 to 15 hours, and within the reaction time, the porous structure of the core is more firmly maintained, so that the porous core and the shell form of a layered structure Can be synthesized in a more complete form.

Hydrothermal synthesis can be carried out by stirring the reactant solution for the above time at the above temperature conditions or by standing without stirring, and other conditions of hydrothermal synthesis can be appropriately selected and performed as conditions for smooth crystallization reaction. have.

In addition, according to an embodiment of the present invention, after the step of hydrothermal synthesis to form a layered silicate, 3) a step of recovering the layered silicate may be further included.

At this time, generally known separation and recovery methods may be applied without limitation, and layered silicate may be separated and recovered from the mixture after the reaction by any method known to those skilled in the art such as filtration.

In addition, according to an embodiment of the present invention, after the recovery step, 4) washing the layered silicate and 5) drying the layered silicate may be further included.

The washing may be performed using water as a washing solvent, and more preferably, washing may be performed using deionized water. In addition, the drying may be performed for 1 to 15 hours at a temperature of 50 to 200°C. In addition, the drying may be preferably performed under atmospheric pressure, but changing the pressure conditions is not excluded from the scope of the present invention.

According to another embodiment of the present invention, a porous core; And a shell made of a layered structure, wherein the core and the shell are made of silica, providing a layered silicate in the form of a core-shell. Here, the layered silicate may be synthesized by the above synthesis method.

Here, the layered structure constituting the shell may represent a flower-like lamellar structure formed during the synthesis of magadite or kenyite.

In addition, the porous core may have any shape as long as it has a porous structure with many pores, for example, it may have a shape such as a sphere or an ellipse, and is formed by dissolving and reprecipitating silica from the silica source. Therefore, an amorphous porous silica core formed through dissolution and reprecipitation may also be included in the scope of the present invention.

Since the layered silicate according to an embodiment of the present invention has excellent adsorption and exchange properties, it may be particularly suitable for adsorption of water or organic molecules and exchange of cationic surfaces. In addition, since the layered structure is easily dispersed between layers, it can be used as a reinforcing agent, filler, nanocomposite, etc. for organic materials such as polymers and pharmaceuticals. In this case, when forming the core-shell structure according to the present invention, unlike general magadite or kenyite, since it contains a porous core, the adsorption capacity can be improved, and the adsorption or exchange capacity can be greatly improved. In addition, since the specific surface area of the core is high, materials such as polymers, pharmaceuticals, and enzymes intercalated can be more easily penetrated, and thus, compatibility with materials such as polymers can be significantly improved.

In addition, unlike the porous core, the surface forms a shell having a dense layered structure, and the outside of the particles forms a closed structure, so that it can be used as a microreactor or a drug delivery material.

Since the layered silicate according to the present invention can be controlled in a core-shell structure as described above, the application range is very wide even compared to the general layered silicate, and the industrial application is very excellent.

Hereinafter, the present invention will be described in more detail by examples and experimental examples. However, the following examples and experimental examples are for illustrative purposes only, and the scope of the present invention is not limited thereto.

Manufacturing Example 1

Water glass (sodium silicate, Youngil Chemical, silica content 28 ~ 30% by weight, SiO ₂ :Na ₂ O = 3.52: 1) and distilled water to prepare a water glass solution having a SiO ₂ content of 8% by weight, hexane and 1 Mixing in a :1 volume ratio to prepare a silica precursor solution. To the silica precursor solution, a surfactant sorbitan monooleate (SPAN80) was added in a volume ratio of 5%. Then, an emulsion was formed by stirring at 800 rpm using a stirrer. Silica gel was prepared by adding acetic acid as a neutralizing agent in a volume ratio of 10% of the mixed solution, and isopropanol as a gelling agent in a volume ratio of mixed solution:gelling agent=1:2. Ethanol was added to the gelled silica to separate the hexane layer and the phase, followed by washing with water three times. Thereafter, ethanol was added again, washed three times, and dried in an oven at 150° C. to prepare spherical silica particles. The prepared spherical silica particles were removed from relatively large particles using a 63 µm sieve, and then small particles were removed using a 45 µm sieve so that the average particle diameter (D50) was 50 µm. At this time, the formation of spherical silica particles can be confirmed by the SEM photograph (100 times magnification) of FIG. 1.

Manufacturing Example 2

Spherical silica particles were prepared in the same manner as in Preparation Example 1, except that the stirring speed was changed to 900 rpm in Preparation Example 1. The prepared spherical silica particles were removed using a 45 µm sieve to remove relatively large particles, and then small particles were removed using a 25 µm sieve so that the average particle diameter (D50) was 35 µm. At this time, the formation of spherical silica particles can be confirmed by the SEM photograph (100 times magnification) of FIG. 2.

Comparative Preparation Example 1

After diluting water glass (sodium silicate, Youngil Chemical, silica content 28 to 30% by weight, SiO ₂ :Na ₂ O = 3.52: 1) and distilled water to prepare 100 ml of a water glass solution having a SiO ₂ content of 8% by weight, acetic acid Add 6 ml to gel. Thereafter, the prepared gel was crushed using a hand mixer, and dried under the same conditions as in Preparation Example 1 to prepare amorphous silica particles. Formation of the amorphous silica particles can be confirmed by the SEM image (1000 times magnification) of FIG.

Comparative Preparation Example 2

Spherical silica particles were prepared in the same manner as in Preparation Example 1, except that the stirring speed was changed to 3000 rpm in Preparation Example 1, and at this time, the average particle diameter (D50) of the spherical silica particles was 5 μm.

Example 1

After mixing the spherical silica particles of Preparation Example 1, sodium hydroxide, and deionized water at a molar ratio of 5:1:150, put into a Teflon-coated autoclave reactor, and heat treated at 195°C for 12 hours to proceed with a hydrothermal synthesis reaction. . Then, the synthesized product was recovered, washed 3 times with deionized water, and dried at 150° C. for 6 hours to prepare a final layered silicate.

Example 2

A layered silicate was prepared in the same manner as in Example 1, except that the hydrothermal synthesis reaction was performed by heat treatment for 15 hours.

Example 3

A layered silicate was prepared in the same manner as in Example 1, except that the hydrothermal synthesis reaction was performed by heat treatment for 18 hours.

Example 4

A layered silicate was prepared in the same manner as in Example 1, except that a hydrothermal synthesis reaction was performed by heat treatment at 185°C.

Example 5

A layered silicate was prepared in the same manner as in Example 1, except that the spherical silica particles of Preparation Example 2 were used.

Comparative Example 1

A layered silicate was prepared in the same manner as in Example 1, except that the amorphous silica particles of Comparative Preparation Example 1 were used.

Comparative Example 2

A layered silicate was prepared in the same manner as in Example 1, except that the spherical silica particles prepared in Comparative Preparation Example 2 were used.

Experimental example

1) Layered silicate structure analysis

In order to confirm the morphology of the layered silicate prepared in Examples and Comparative Examples, it was observed with a magnification of 1000 to 10,000 times using a scanning electron microscope (S4800, Hitachi), and the results are shown in FIGS. 4 to 11. Done.

As shown in Figs. 4 to 11, the layered silicate prepared according to the synthesis method of the embodiment has a core-shell structure including a porous core and a shell having a layered structure in the form of a blossom, whereas the production according to the synthesis method of the comparative example It can be seen that the layered silicate formed only the layered structure of the general magadite or Kenyite in the form of a flower, and the porous core was not formed.

Specifically, FIGS. 4 and 5 are SEM photographs taken by adjusting the magnification of 1000 times and 5000 times with the layered silicate of Example 1. In the layered silicate of FIGS. 4 and 5, it can be confirmed that a flower-shaped layered structure shell is formed and a porous structure core is formed therein, and the shape can be more easily confirmed in the high magnification photograph of FIG. 5.

FIG. 6 is a SEM photograph of the layered silicate of Example 2, FIG. 7 is an SEM photograph of the layered silicate of Example 3, and FIG. 8 is an SEM photograph of the layered silicate of Example 4, and FIG. 9 Is a SEM photograph of the layered silicate of Example 5 by adjusting each of the different magnifications. 6 to 9, as shown in FIGS. 4 and 5, it can be seen that a porous core and a flower-shaped layered structure shell are formed.

In addition, among the examples, when comparing FIGS. 4 to 7, it can be seen that the porous core structure of FIGS. 4 and 5 manufactured by the manufacturing method of Example 1 is most firmly maintained.

In contrast, FIG. 10, which is an SEM photograph of Comparative Example 1 in which a layered silicate was prepared using amorphous silica particles, and FIG. 10, which is an SEM photograph of Comparative Example 2 in which spherical silica particles were used as a silica source, but the average particle diameter was less than 20 μm. Fig. 11 shows that no porous core structure was observed in the prepared layered silicate, and only a flower-shaped layered structure, which is a general magadite or kenyite structure, was formed.

2) X-ray diffraction analysis (XRD)

The layered silicate prepared in Example 1 was subjected to X-ray diffraction analysis, and the results are shown in FIG. 12. At this time, X-ray diffraction analysis was performed by powder XRD method using Bruker's D4 from 2 theta 10° to 70° every 0.02° for 87.5 seconds.

The XRD diffraction analysis graph of FIG. 12 is a result of measuring the layered silicate prepared in Example 1, and it can be seen that the silica of the core exists in the form of quartz and the silica of the layered structure of the shell exists in the form of kenite. Through this, it can be seen that the layered silicate prepared in the embodiment of the present invention has a core-shell structure.

Claims (12)

1) forming a reactant solution by mixing a silica source, a basic substance, and water; And
2) hydrothermal synthesis of the reactant solution to form a layered silicate; including,
The silica source is a method for synthesizing a layered silicate that is a spherical silica particle having an average particle diameter (D50) of 20 μm or more.
The method of claim 1,
The silica particles have an average particle diameter (D50) of 20 to 60 µm.
The method of claim 1,
The silica particles are silica particles on the spherical secondary particles formed by agglomeration of the silica particles on the primary particle layered silicate synthesis method.
The method of claim 1,
The basic material, silica source, and water are mixed in a molar ratio of 1:1:50 to 1:25:500.
The method of claim 1,
The hydrothermal synthesis is a layered silicate synthesis method to be carried out for 1 to 50 hours at a temperature of 100 to 250 ℃.
The method of claim 1,
The hydrothermal synthesis is a layered silicate synthesis method that is performed for 5 to 25 hours.
The method of claim 1,
The basic material is a layered silicate synthesis method comprising at least one selected from the group consisting of sodium hydroxide (NaOH), potassium hydroxide (KOH), sodium carbonate (Na ₂ CO ₃ ) and sodium hydrogen carbonate (NaHCO ₃ ).
The method of claim 1,
The layered silicate is a method for synthesizing a layered silicate that is magadite or kenite.
The method of claim 1,
The silica source is a method of synthesizing a layered silicate that is a reaction product produced by reacting a silica material, a neutralizing agent, and a gelling agent.
The method of claim 9,
The silica material is a layered silicate synthesis method comprising a water glass solution.
Porous core; And
It includes a shell made of a layered structure,
Layered silicate wherein the core and the shell are made of silica.
The method of claim 11,
The layered silicate is a layered silicate that is magadite or kenite.

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