KR100443562B1 - Noble preparation method of kit-3 and aikit-3 materials that are mesoporous molecular sieve substances and the mesoporous molecular sieve substances prepared by the method - Google Patents

Abstract

PURPOSE: To provide a preparation method of improved mesoporous molecular sieve substance capable of improving hydrothermal stability of MCM-41 material and the mesoporous molecular sieve substance prepared by the method. CONSTITUTION: The preparation method of mesoporous molecular sieve substance comprises a step (A) of preparing a mixed aqueous solution of halogenated alkyltrimethylammonium, ammonia aqueous solution and silicate represented by the following formula 1 as a surfactant: £Formula 1| CnH2n+1(CH3)3NX where n is an integer of 12 to 18, and X is Cl or Br; a step (B) of hydrothermal reacting the pH adjusted reacted mixture again after hydrothermal reacting a mixture of the step (A) and adjusting pH of the reacted mixture; a step (C) of adding one or more organic salts or inorganic salts capable of being bonded to monovalent cations and dissolved into water to the reacted mixture of the step (B); a step (D) of hydrothermal reacting the pH adjusted reacted mixture again after hydrothermal reacting a mixture of the step (C) and adjusting pH of the reacted mixture; a step (E) of hydrothermal reacting a mixture of the step (D) again by maintaining pH, temperature and time of the mixture to form precipitate of a final desired molecular sieve substance; a step (F) of filtering, washing and drying the precipitate of the molecular sieve substance formed in the step (E); and a step (G) of firing the precipitate filtered, washed and dried in the step (F). The mesoporous molecular sieve substance is prepared by the method and constructed in such a structure that straight line-shaped mesopores having certain size are arranged in a hexagonal shape.

Description

Method for producing medium porous molecular sieve material and molecular sieve material thereof

The present invention relates to a novel method for preparing KIT-3 and AlKIT-3 materials, which are mesoporous molecular sieve substances, and to molecular sieve materials prepared by the method. Hydrothermal stability by adding various inorganic or organic salts during hydrothermal preparation process of KIT-3 and AlKIT-3 materials to enhance hydrothermal stability, which has been a limiting catalytic application in the existing MCM-41 material, a medium-porous molecular sieve It relates to a manufacturing method that can greatly increase the.

Porous materials are classified as microporous materials when the processing size is 2 nm or less, mesoporous materials when 2 to 50 nm, and macroporous materials when 50 nm or more. Among these porous materials, materials with uniformly arranged pores such as zeolites are defined as molecular sieves, and hundreds of species have been discovered or synthesized so far. Zeolites play an important role as catalysts or catalyst carriers in the modern chemical industry due to their inherent properties such as selective adsorption, acidity and ion exchange capacity. However, since the zeolite is a molecular sieve having micropores, the size of the molecule that can be applied to the catalytic conversion reaction is limited by the pore size. For example, when performing catalytic cracking with ZSM-5 zeolite, the reactivity decreases significantly as the reactant is changed from n-alkane to cycloalkane or branched alkanes. Thus, until recently, many researchers around the world have been trying to synthesize molecular sieves with larger pore sizes than zeolites, such as AlPO ₄ , VPI-5, Cloverlite and JDF-20. However, even in these molecular sieves, the pore size does not escape the scope of micropores. Among these, new mesoporous molecular sieves, named MCM-41 materials, were prepared by US researchers at Mobil Corporation and published in US Pat. Nos. 5,057,296 and 5,102,643. The MCM-41 material is a material having a hexagonal array of uniformly sized pores on a silica sheet, that is, a honeycomb lined structure. MCM-41 materials are known to be produced via the liquid crystal mold pathway, according to recent studies. That is, the surfactant forms a liquid crystal structure in an aqueous solution, and a silicate ion surrounds the surroundings to form a conjugate of the surfactant and the MCM-41 material through a hydrothermal reaction, and the surfactant is heated at a temperature of 500 to 600 ° C. When removed by calcination at, MCM-41 material can be obtained. In this case, if the manufacturing conditions are changed, such as changing the type of surfactant or adding other organic materials, the pore size may be changed to 1.6 to 10 nm. Therefore, the MCM-41 material is a molecular sieve that extends the pore size to medium pore size compared to conventional molecular sieves such as zeolites, and many researchers around the world are actively researching its properties and applications. For example, MCM-41 is a model adsorbent, which is used to study the adsorption characteristics of various gases as it is a structurally homogeneous medium-sized porous material. It may be used as a carrier such as polyacid. In addition, MCM-41 materials in which other elements (aluminum, boron, manganese, iron, vanadium, titanium, etc.) are substituted in the skeleton are also produced, and studies are being actively conducted to apply them to catalytic reactions of macroorganic compounds or as catalyst carriers. .

As mentioned above, many applications of MCM-41 materials have been published. One of the most important physical properties for these applications is thermal stability. The MCM-41 materials published by the early researchers produced 20% to 25% shrinkage of the structure before firing, although slightly different depending on the manufacturing conditions when firing to remove the mold material. This is a phenomenon caused by condensation. However, recent studies have shown that this weak heat can be achieved by shifting the equilibrium of the silicic acid condensation reaction towards the product by properly adjusting the pH of the reaction mixture during the hydrothermal preparation of the MCM-41 material, as the condensation of silanol groups is completed in the reaction mixture in advance. It has been reported that the stability can be overcome and the yield and structure uniformity of the prepared MCM-41 material can be greatly improved. The MCM-41 material thus prepared has only a slight contraction even when heated to 900 ° C. under an oxygen atmosphere containing air or 2.3 kPa of water vapor, and has a stable structure and a temperature of up to 500 ° C. under a 100% water vapor atmosphere of 1 atmosphere. It has excellent thermal stability that the structure does not collapse.

However, despite the excellent thermal stability of MCM-41, when the water temperature is above 60 ℃, the silicate, which forms the structure of the molecular sieve, is hydrolyzed, and the structure starts to decay slowly. Doing so will completely lose its structural characteristics. This weak hydrothermal stability is due to the catalytic activity of the catalytic conversion material such as platinum ion or in the case of catalytic conversion reactions requiring hydrothermal conditions such as hydrogen peroxide as an oxidant when titanium is used for partial oxidation of molecular sieves substituted in the structure. This is a very serious limitation when a temperature of 60 ° C. or higher is required when supported in the body. Therefore, it has been a challenge to prepare a medium-porous molecular sieve material with enhanced hydrothermal stability.

Accordingly, an object of the present invention is to provide a method for preparing an improved medium-porous molecular sieve material which can improve the hydrothermal stability of the aforementioned MCM-41 material, and another object is to provide a medium-porous molecular sieve prepared by the above method. To provide a substance. The present invention is related to Korean Patent Application No. 97-52841, the present applicant of which is pending in the Republic of Korea on November 8, 1997, which application is referred to in the present invention.

The production method of the present invention for achieving the above object comprises the steps of (A) preparing a mixed aqueous solution of alkyltrimethylammonium halide, ammonia aqueous solution and silicate represented by the following formula 1 as a surfactant; (B) hydrothermally reacting the reaction mixture of step (A), and then adjusting the pH of the reaction mixture and performing hydrothermal reaction again; (C) adding one or two or more of an organic salt or an inorganic salt which can be combined with a monovalent cation and can be dissolved in water to the reaction mixture of step (B); (D) hydrothermally reacting the reaction mixture of step (C), and then adjusting the pH of the reaction mixture and performing hydrothermal reaction again; (E) hydrothermally reacting the reaction mixture of step (D) again by maintaining pH, temperature and time so as to form a precipitate of the final desired molecular sieve material; (F) filtering, washing and drying the precipitate of the molecular sieve material formed in step (E); And (G) calcining, washing and drying the precipitate in (F).

[Formula 1]

C _n H _{2n + 1} (CH ₃ ) ₃ X

N is an integer of 12 to 18, and X is Cl or Br.

Another method for preparing the present invention is (1) one or two in the group consisting of alkyltrimetalammonium halide, ammonia solution, silicate and aluminate, boronate and 3d transition metal salt of the periodic table represented by Formula 1 as surfactants. Preparing a reaction mixture of the salts selected above; (2) hydrothermally reacting the reaction mixture of step (1), and then adjusting the pH of the reaction mixture and performing hydrothermal reaction again; (3) adding to the reaction mixture of step (2) one or more selected from organic salts or inorganic salts which can be combined with monovalent cations and are soluble in water; (4) hydrothermally reacting the reaction mixture of step (3), and then adjusting the pH of the reaction mixture and hydrothermally reacting again; (5) hydrothermal reaction of the reaction mixture of step (4) again by maintaining pH, temperature and time so as to form a precipitate of the final desired molecular sieve material; (6) filtering, washing and drying the precipitate of the molecular sieve material formed in step (5); And (7) firing the precipitate filtered, washed and dried in step (6).

In order to achieve another object of the present invention, the mesoporous molecular sieve material is manufactured by the above-described manufacturing methods, and has a hexagonal array structure in which the straight-shaped medium pores having a constant size are arranged in a hexagonal shape. The mesoporous molecular sieve material prepared by the first method was named KIT-3 and the mesoporous molecular sieve material prepared by the second method was named ALKIT-3 below.

1 is a transmission electron micrograph of a KIT-3 material prepared in one embodiment of the present invention.

FIG. 2 is an X-ray diffraction graph of the KIT-3 material of FIG. 1.

FIG. 3 is a graph showing nitrogen adsorption-desorption isotherms obtained at liquid nitrogen temperature for the calcined KIT-3 material of FIG. 2.

4 is a graph showing the pore size distribution obtained by the Horvarth-Kawazoe method from the nitrogen adsorption-desorption isotherm of FIG. 3.

5 is prepared by changing the alkyl chain length of the alkyl aryltrimethylammonium halide (ATAX, C _n H _{2n + 1} (CH ₃ ) ₃ NX, n = 12-18, x = Cl, Br) as an active agent in Example 1 X-ray diffraction graphs for each KIT-3 material.

FIG. 6 is an X-ray diffraction graph of KIT-3 materials prepared using EDTANa ₄ as a salt in Example 2. FIG.

7 is an X-ray diffraction graph of KIT-3 materials prepared using CH ₃ COONa as a salt in Example 3. FIG.

FIG. 8 is an X-ray diffraction graph of KIT-3 materials prepared using LiCl as a salt in Example 4. FIG.

9 is an X-ray diffraction graph of KIT-3 materials prepared using NaCl as a salt in Example 5. FIG.

FIG. 10 is an X-ray diffraction graph of KIT-3 materials prepared using KCl as a salt in Example 6. FIG.

FIG. 11 is an X-ray diffraction graph of KIT-3 materials prepared using NaNO ₃ as a salt in Example 7.

FIG. 12 is an X-ray diffraction graph of KIT-3 materials prepared using Na ₂ SO ₄ as a salt in Example 8.

FIG. 13 shows the results of solid-state MAS aluminum-27 nuclear magnetic resonance experiments obtained after various treatments for calcined KIT-3 (AlKIT-3, Si / Al = 40) materials synthesized by substituting aluminum in a skeleton structure in Example 9 Is a graph.

FIG. 14 is a temperature controlled desorption experiment of ammonia adsorbed on a sample obtained after various treatments for a calcined KIT-3 (AlKIT-3, Si / Al = 40) material synthesized by substituting aluminum in a skeleton structure in Example 9. FIG. A graph showing the results.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As mentioned above, the MCM-41 material, which is a mesoporous molecular sieve, is prepared through a liquid crystal mold route using a surfactant as a structure-inducing substance. According to the existing research results, a variety of methods for producing MCM-41 materials have been published, but in the present invention, based on the methods of the present inventors (J. Chem. Soc., Chem. Commun., 1995, 711), KIT- Three materials were prepared. The surfactant used in the present invention is an alkyltrimethylammonium halide represented by Formula 1, preferably dodecyltrimethylammonium bromide (DTABr), tetradecyltrimethylammonium bromide (TTABr), hexadecyltrimethylammonium chloride (HTACl), Octadecyltrimethylammonium bromide (OTABr). As a silicate source used in the above steps (A) and (1), a sodium silicate aqueous solution (Na / Si = 0.5) in which the colloidal silica Luodx HS40 (40 wt% SiO ₂ ), DuPont Co., Ltd., was dissolved in a 1M aqueous solution of sodium hydroxide. However, the present invention is not limited thereto, and various silicate sources may be used. Sodium aluminate (NaAlO ₂ ) is one example of one or more selected salts from the group consisting of aluminates, boronates and 3d transition metal salts on the periodic table used in step (1). According to the method for preparing the KIT-3 material of the present invention, the process of neutralizing the pH of the reaction mixture to 10.2 using a weak acid, for example, acetic acid, is performed three times. After the first pH neutralization in the manufacturing process of the hydrothermal reaction after the addition of the salt was added to obtain a material with improved thermal stability and hydrothermal stability. That is, unlike the Republic of Korea Patent Application No. 97-52841, which is an earlier application of the present invention, step (B) or (2) is added and then the salt is used by adding the salt used in step (C) or (3). And it was possible to obtain a medium porous material with a different pore structure. That is, the first application is connected in a three-dimensional disordered cavity, but the present invention has a structure in which the straight-line medium pores having a constant size is arranged in a hexagonal arrangement, that is, a honeycomb. The meaning of the hydrothermal reaction used in the specification of the present invention can be easily recognized by those skilled in the art, but usually this is in English while heating using water as a solvent in a closed or unclosed container in a hydrothermal reaction. It means to react in. The salts used in steps (C) and (3) can be combined with monovalent cations (eg, Li ⁺ , Na ⁺ , K ⁺ , Rb ⁺ , NH ₄ ^+, etc.) and dissolved in water. Examples of organic or inorganic salts that may be used include LiCl, NaCl, KCl, RbCl, CH ₃ COONa, NaBr, CH ₃ COOK, Na ₂ SO ₄ , NaNO ₃ , NaClO ₄ , NaClO ₃ , sodium ethylenediaminetetraacetic acid (EDTANa ₄ Adipic acid disodium salt, 1,3-benzendisulfonic acid disodium salt, or sodium nitrilotriacetic acid salt is preferable. In steps (A) and (1), 1.0 to 15.0 moles of silicate may be used based on 1 mole of alkyltrimethylammonium halide. The aqueous ammonia solution used in steps (A) and (1) was added to facilitate the role of the surfactant, but may not be used in some cases. In step (1), 0.0025 to 0.40 mol of a salt selected from one or more selected from the group consisting of aluminate, boron salt and 3d transition metal salt on the periodic table based on 1 mol of the alkyltrimethylammonium halide represented by Chemical Formula 1 is used. It is preferable. In step (B) and step (2), the hydrothermal reaction temperature is suitably 80 to 120 ° C., and the time is suitably 1 to 2 days, and other hydrothermal reactions are the same. 0.5 to 16.0 moles of inorganic or organic salts that can be combined with a monovalent cation and dissolved in water based on 1 mole of alkyltrimethylammonium halide represented by Formula 1 in steps (C) and (3) are used. It is suitable. In addition, in the last step, it is preferable to calcinate at 500 to 600 ° C. under an air atmosphere.

1 is a transmission electron microscope of a KIT-3 material having a molar ratio of reactants in a reaction mixture in Example 1 of 4 SiO ₂ : 1 HTACl: 1 Na ₂ O: 0.15 (NH ₄ ) ₂ O: 200 H ₂ O It is a photograph. As shown in FIG. 1, the KIT-3 material has a hexagonal arrangement, that is, a honeycomb lined structure, in which a straight-shaped medium pore having a constant size is formed. All KIT-3 materials prepared in the present invention An electron micrograph similar to that of FIG. 1 was also obtained from FIG. Figure 2 is a characteristic X-ray diffraction pattern of the KIT-3 material shown in the transmission electron micrograph in Figure 1 (a) is for the material before the firing treatment, (b) is for the material after the firing treatment. X-ray diffraction patterns, before and after firing treatment, show peaks of (100) and (110), (200), (210) and (300) in the low angle region, which can be represented in a hexagonal arrangement. Figure 3 is fired absorption of nitrogen in the process after the liquid nitrogen temperature as in Example 1 to the KIT-3 material shown in Figure 1 - of the adsorbed amount of nitrogen in the vicinity of the result obtained by the desorption experiment P / P ₀ 0.4 The pore size distribution curve obtained by Horvath-Kawazoe's method from the nitrogen adsorption-desorption isotherm shows an abrupt transition. ). These nitrogen adsorption-desorption results show a similar shape regardless of the type of salt used during the preparation of the KIT-3 material (not shown). FIG. 5 is an X-ray diffraction pattern of KIT-3 material prepared by changing the type of surfactant in Example 1. FIG. At this time, the salt added during the manufacturing process was EDTANa ₄ and the number of moles of salt per mol of the surfactant was fixed to 8. In FIG. 5, the length (n value) of the alkyl chain of the alkyltrimethylammonium halide represented by Chemical Formula 1 used as a surfactant is increased to 12 (a), 14 (b), 16 (c), and 18 (d). As it can be seen that the d ₁₀₀ value of the X-ray diffraction pattern increases constantly from 2.5nm to 4.6nm. 6 to 12 show that salts used in the form of X-ray diffraction according to the type of salt added during the preparation of the KIT-3 material are EDTANa ₄ , CH ₃ COONa, LiCl, NaCl, KCl, NaNO ₃ , Na _{2 is} SO ₄ . 6 to 12, the X-ray diffraction pattern on the left is for the materials after the surfactant is removed by firing the prepared KIT-3 material, and the X-ray diffraction pattern on the right is the respective firing. KIT-3 was added to boiling water for 12 hours. 6 is a result of preparing a KIT-3 material using EDTANa ₄ as a salt as in Example 2, the left side of which is the form of X-ray diffraction after firing for each sample and the right side of the calcined sample in boiling water X-ray diffraction pattern after 12 hours in the stomach. Figures in the figure indicate the number of moles of EDTANa ₄ added to 1 mole of hexadecyltrimethylammonium chloride as a surfactant in the reaction mixture, and used in the range of 0 to 16 moles. As can be seen in the figure, the KIT-3 material prepared without using any salt is left in boiling water for 12 hours and its structure is completely degraded. On the other hand, the addition of salts during the manufacture of KIT-3 materials changes the degree of breakdown of the structure depending on the amount. That is, in Example 2, as the ratio of EDTANa ₄ and the surfactant is increased, the hydrothermal stability of the structure is gradually increased. In Figures 7 to 12, KIT-3 materials were prepared using CH ₃ COONa, LiCl, NaCl, KCl, NaNO ₃ , Na ₂ SO ₄ as salts in Examples 3, 4, 5, 6, 7 and 8 below. The X-ray diffraction pattern (left) of the calcined material after preparation and the x-ray diffraction form (right) after hydrothermal treatment for 12 hours in boiling water for each calcined material are shown. 6, the numbers shown in the drawings indicate the number of moles of the salt added to 1 mole of hexadecyltrimethylammonium chloride as a surfactant in the reaction mixture. 7 to 12, similar to that shown in FIG. 6, when the KIT-3 material is added with other salts during the manufacturing process, hydrothermal stability gradually increases as the amount of salt increases, and then decreases after the peak. In each case, 2 moles of CH ₃ COONa and 3 moles of LiCl, 3 moles of NaCl, 2 moles of KCl, 2 moles of NaNO ₃ , and 2 moles of Na ₂ SO ₄ per mole of hexadecyltrimethylammonium chloride When added, the hydrothermal stability of KIT-3 material was maximized.

In Example 9 below, a structure in which a part of silicon was substituted with aluminum in the skeleton of KIT-3 (AlKIT-3, Si / Al = 10 to 200) was prepared by adding EDTANa ₄ as a salt. It can be confirmed that the structure of AlKIT-3 is the same as KIT-3 (not shown). 13 and 14 show the results of solid-state magic angular rotation (MAS) aluminum-27 nuclear magnetic resonance spectroscopy (NMR) experiments after various thermal and hydrostability experiments were performed on samples having a Si / Al ratio of 40 in Example 9. The result of a temperature controlled desorption (TPD) experiment of ammonia gas on a sample of (a) is the material before the firing treatment, (b) is the material after the firing treatment, and (c) is an oxygen atmosphere containing 2.3 kPa of water vapor. The material after holding for 2 hours at 500 ℃ under, (d) is for the material after holding for 12 hours in boiling water at 100 ℃. AlKIT-3, like KIT-3 described above, has almost no collapse of the structure due to heat treatment or hydrothermal treatment due to the added salt effect, and it can be seen that aluminum contained in the structure maintains the tetrahedral structure. Referring to FIG. 14, the AlKIT-3 was treated for 2 hours in an oxygen atmosphere containing 2.3 kPa of water vapor at 500 ° C. (c) or for 12 hours in boiling water at 100 ° C. (d). It can be seen that AlKIT-3 has high thermal stability and hydrothermal stability.

The following examples are intended to explain in detail the various synthesis methods and applications of KIT-1 and AlKIT-3, which are the subject matter of the present invention, and the scope of the present invention is not limited thereto.

Example 1

Example 1 relates to changing the alkyl chain lengths of the surfactant alkyltrimethylammonium halide (ATAX) to 12 and 14, 16 and 18 in the preparation of the KIT-3 material. Solution A is 25 wt% aqueous dodecyltrimethylammonium bromide (DTABr) and 25 wt% tetradecyltrimethylammonium bromide (TTABr), 25 wt% aqueous hexadecyltrimethylammonium chloride (HTACl), and 25 wt% octadecyl bromide, respectively, as shown in Table 1. 0.29 g of 28 wt% aqueous ammonia was mixed with an aqueous trimethylammonium (OTABr) solution. Solution B was prepared by adding 9.4 g of Ludox HS40 (colloidal silica, manufactured by Dupont) to 33.8 g of 1.0 M sodium hydroxide solution, and heating at 80 ° C. for 2 hours. Solution C was prepared by preparing an aqueous solution of 33.3 wt% sodium ethylenediaminetetraacetate (EDTANa ₄ ), and then using a 0.01 mol sodium hydroxide solution so that the pH of the solution was 11. The solution A was poured into a polypropylene bottle, and the solution B was dropped one by one while stirring vigorously with a magnetic stirrer and mixed at room temperature, followed by stirring for 1 hour. At this time, the composition of the reaction mixture was 4 SiO ₂ : 1 ATAX: 0.15 (NH ₄ ) ₂ O: 200 H ₂ O. After the reaction mixture was hydrothermally reacted at 100 ° C. for 1 day, the mixture was cooled to room temperature and the cooled mixture was stirred to drop the 30 wt% acetic acid aqueous solution dropwise to adjust the pH of the reaction mixture to 10.2. The reaction mixture was further reacted at 100 ° C. for one more day, and then cooled to room temperature to add 140 g of Solution C to 8 mol of EDTANa _{4 relative} to 1 mol of alkyltrimethylammonium halide, a surfactant in the reaction mixture. The mixture was reacted again at 100 ° C. for 1 day, cooled to room temperature, and then the pH was adjusted to 10.2 twice. The precipitate thus produced was filtered, washed clean with secondary distilled water, and dried at 100 ° C. It was calcined at 540 ° C. for 10 hours in air to remove the surfactant in the dried sample. X-ray diffraction patterns of each of the KIT-3 materials thus obtained are shown in FIG. 5 and Table 1 below, in which the value of d ₁₀₀ is changed according to the alkyl chain length. The surface area determined by BET method from nitrogen adsorption was 1000 ± 50m ² g ⁻¹ and the respective values are shown in Table 1 below.

TABLE 1

Type and amount of aqueous alkyltriketylammonium halide (ATAX) aqueous solution used in Example 1, d ₁₀₀ value in the form of X-ray diffraction for each prepared material and surface area determined from nitrogen adsorption method

Example 2

Solution A was prepared by mixing 0.29 g of 28 wt% aqueous ammonia solution with 20 g of 25 wt% aqueous solution of hexadecyltrimethylammonium chloride (HTACl). Solution B was an aqueous sodium silicate solution used in Example 1. Solution C was a 33.3 wt% EDTANa ₄ aqueous solution used in Example 1. The amount of solution C used is shown in Table 2 below. The rest of the preparation was the same as in Example 1, and the molar ratio of the reactants in the reaction mixture after the addition of the salt was 4 SiO ₂ : 1 HTACl: 1 Na ₂ O: 0.15 (NH ₄ ) ₂ O: x EDTANa ₄ : y H ₂ O . (0≤x≤16, 200≤y≤900) X-ray diffraction pattern of each obtained KIT-3 and X-ray diffraction pattern after firing the treated sample for 12 hours in boiling water are shown in FIG. Same as

TABLE 2

Amount of EDTANa ₄ Aqueous Solution Used in Example 2

Example 3

Solution A and Solution B are the same as those used in Example 2. Solution C prepared a 27.0wt% CH ₃ COONa aqueous solution and the amount is shown in Table 3 below. The rest of the preparation is the same as in Example 1, the molar ratio of the reactants in the reaction mixture after the addition of salt is 4 SiO ₂ : 1 HTACl: 1 Na ₂ O: 0.15 (NH ₄ ) ₂ O: x CH ₃ COONa: y H ₂ O. (0≤x≤16, 200≤y≤400) The X-ray diffraction pattern of each obtained KIT-3 and the X-ray diffraction pattern after firing the treated samples for 12 hours in boiling water are shown in FIG. Same as

TABLE 3

Amount of CH ₃ COONa Aqueous Solution Used in Example 3

Example 4

Solution A and Solution B are the same as those used in Example 2. Solution C is a 20.0wt% lithium chloride (LiCl) aqueous solution and the amount added is shown in Table 4 below. The rest of the preparation was the same as in Example 1, and the molar ratio of the reactants in the reaction mixture after the addition of the salt was 4 SiO ₂ : 1 HTACl: 1 Na ₂ O: 0.15 (NH ₄ ) ₂ O: x LiCl: y H ₂ O . (0≤x≤3, 200≤y≤230) The X-ray diffraction pattern of each obtained KIT-3 and the X-ray diffraction pattern after the calcined sample for 12 hours in boiling water are shown in FIG. Same as

TABLE 4

Amount of LiCl Aqueous Solution Used in Example 4

Example 5

Solution A and Solution B are the same as those used in Example 2. Solution C prepared a 25.0 wt% sodium chloride (NaCl) aqueous solution and the amount is shown in Table 5 below. The rest of the preparation was the same as in Example 1, and the molar ratio of the reactants in the reaction mixture after the addition of the salt was 4 SiO ₂ : 1 HTACl: 1 Na ₂ O: 0.15 (NH ₄ ) ₂ O: x NaCl: y H ₂ O . (0≤x≤8, 200≤y≤280) The X-ray diffraction pattern of each KIT-3 thus obtained and the calcined treatment 8 sample after treatment for 12 hours in boiling water are shown in FIG. Same as

TABLE 5

Amount of Solution NaCl Aqueous Solution Used in Example 5

Example 6

Solution A and Solution B are the same as those used in Example 2. Solution C prepared a 20.0 wt% potassium chloride (KCl) aqueous solution and the amount added is shown in Table 6 below. The rest of the preparation was the same as in Example 1, and the molar ratio of the reactants in the reaction mixture after the addition of the salt was 4 SiO ₂ : 1 HTACl: 1 Na ₂ O: 0.15 (NH ₄ ) ₂ O: x KCl: y H ₂ O . (0≤x≤8, 200≤y≤350) The X-ray diffraction pattern of each obtained KIT-3 and the X-ray diffraction pattern after treatment of the calcined sample for 12 hours in boiling water are shown in FIG. Same as

TABLE 6

Amount of Solution KCl Aqueous Solution Used in Example 6

Example 7

Solution A and Solution B are the same as those used in Example 2. Solution C prepared a 25.0 wt% sodium nitrate (NaNO ₃ ) aqueous solution and the amount is shown in Table 7 below. The rest of the preparation is the same as in Example 1, the molar ratio of the reactants in the reaction mixture after the addition of salt is 4 SiO ₂ : 1 HTACl: 1 Na ₂ O: 0.15 (NH ₄ ) ₂ O: x NaNO ₃ : y H ₂ O to be. (0≤x≤2, 200≤y≤280) The X-ray diffraction pattern of each obtained KIT-3 and the X-ray diffraction pattern after the calcined sample for 12 hours in boiling water are shown in FIG. Same as

TABLE 7

Amount of Solution NaNO ₃ Aqueous Solution Used in Example 7

Example 8

Solution A and Solution B are the same as those used in Example 2. Solution C prepared a 9.2wt% sodium sulfate (Na ₂ SO ₄ ) aqueous solution and the amount is shown in Table 8 below. The rest of the preparation is the same as in Example 1, the molar ratio of the reactants in the reaction mixture after the addition of salt is 4 SiO ₂ : 1 HTACl: 1 Na ₂ O: 0.15 (NH ₄ ) ₂ O: x Na ₂ SO ₄ : y H ₂ O. (0≤x≤2, 200≤y≤360) The X-ray diffraction pattern of each obtained KIT-3 and the X-ray diffraction pattern after the calcined sample for 12 hours in boiling water are shown in FIG. Same as

TABLE 8

Amount of Na ₂ SO ₄ Aqueous Solution Used in Example 8

Example 9

Solution A, Solution B, and Solution C were the same as those used in Example 2, and the amount of Solution C used was 140 g. Solution D is the amount used in 5.0wt% sodium aluminum oxide (NaAlO ₂ ) aqueous solution is shown in Table 9. The reaction mixture prepared by mixing Solution A and Solution B was stirred at room temperature for 1 hour, and then solution D was slowly added drop by drop, followed by further stirring for 1 hour. The remaining manufacturing method is the same as in Example 1. At this time, the molar ratio of the reactants in the reaction mixture is 4 SiO ₂ : 1 HTACl: 1 Na ₂ O: 0.15 (NH ₄ ) ₂ O: 2 / x Al ₂ O ₃ : y H ₂ O. (10 ≦ x ≦ 200, 200 ≦ y ≦ 220) The reaction mixture was subjected to hydrothermal reaction at 100 ° C. for 2 days. The rest of the manufacturing process is the same as in Example 1.

TABLE 9

Amount of NaAlO ₂ Aqueous Solution Used in Example 9

As described above, the mesoporous molecular sieve KIT-3 material prepared by the addition of salts during the preparation process in the present invention showed superior hydrothermal stability as compared to the material prepared by the conventional method.

Claims (15)

(A) preparing a mixed aqueous solution of alkyltrimethylammonium halide, ammonia solution and silicate represented by Formula 1 as a surfactant; (B) hydrothermally reacting the reaction mixture of step (A), and then adjusting the pH of the reaction mixture and performing hydrothermal reaction again; (C) adding one or two or more of an organic salt or an inorganic salt which can be combined with a monovalent cation and can be dissolved in water to the reaction mixture of step (B); (D) hydrothermally reacting the reaction mixture of step (C), and then adjusting the pH of the reaction mixture and performing hydrothermal reaction again; (E) hydrothermal reaction of the reaction mixture of step (D) again by maintaining pH, temperature and time to form a precipitate of the final desired molecular sieve material; (F) filtering, washing and drying the precipitate of the molecular sieve material formed in step (E); And (G) The method of producing a medium-porous molecular sieve material consisting of calcining, washing and drying the dried precipitate in step (F). [Formula 1] C _n H _{2n + 1} (CH ₃ ) ₃ NX N is an integer of 12 to 18, and X is Cl or Br. The method according to claim 1, wherein the surfactant is hexadecyltrimethylammonium chloride, dodecyltrimethylammonium bromide, tetradecylmethylammonium bromide, or octadecyltrimethylammonium bromide. The method of claim 1, wherein the silicate is sodium silicate. The method of claim 1, wherein the organic salt or inorganic salt which can be combined with the monovalent cation and dissolved in water is LiCl, NaCl, KCl, RbCl, CH ₃ COONa, NaBr, CH ₃ COOK, Na ₂ SO ₄ , NaNO ₃ , NaClO ₄ , NaClO ₃ , sodium ethylenediaminetetraacetic acid, adipic acid disodium salt, 1,3-benzendisulfonic acid disodium salt, or nitrilotriacetic acid Method for producing a medium porous molecular sieve material, characterized in that sodium. According to claim 1, 0.5 to 16.0 moles of organic or inorganic salts that can be combined with a monovalent cation and dissolved in water based on 1 mole of the alkyltrimethylammonium halide of Formula 1, and 1.0 to 15.0 moles of the silicate are used. Method for producing a medium porous molecular sieve material, characterized in that. The method of claim 1, wherein the firing temperature is 500 to 600 ℃. A mesoporous molecular sieve material having a structure in which hexagonal arrays are formed by the process of any one of claims 1 to 6, wherein the linear medium pores having a constant size are arranged in a hexagonal arrangement. (1) preparing a reaction mixture of at least one selected from the group consisting of alkyl halides, ammonium halides, aqueous ammonia, silicates and aluminates, boronates and 3d transition metal salts of the periodic table represented by the above-mentioned surfactants Doing; (2) hydrothermally reacting the reaction mixture of step (1), and then adjusting the pH of the reaction mixture and performing hydrothermal reaction again; (3) adding to the reaction mixture of step (2) one or more selected from organic salts or inorganic salts which can be combined with monovalent cations and are soluble in water; (4) hydrothermally reacting the reaction mixture of step (3), and then adjusting the pH of the reaction mixture and hydrothermally reacting again; (5) hydrothermal reaction of the reaction mixture of step (4) again by maintaining pH, temperature and time so as to form a precipitate of the final desired molecular sieve material; (6) filtering, washing and drying the precipitate of the molecular sieve material formed in step (5); And (7) The method of producing a medium-porous molecular sieve material consisting of calcining the precipitate filtered, washed and dried in step (6). [Formula 1] C _n H _{2n + 1} (CH ₃ ) ₃ NX Wherein n is an integer from 12 to 18 and X is Cl or Br. The method of claim 8, wherein the aluminate is sodium aluminate (NaAlO ₂ ). According to claim 8, 0.5 to 16.0 moles of organic or inorganic salts that can be combined with a monovalent cation and dissolved in water based on 1 mole of alkyltrimethylammonium halide represented by Chemical Formula 1 and the silicate 1.0 to 15.0 Molar and 0.0025 to 0.40 moles of one or more salts selected from the group consisting of aluminates, boronates and 3d transition metal salts on the periodic table are used. The method of claim 8, wherein the surfactant is hexadecyltrimethylammonium chloride, dodecyltrimethylammonium bromide, tetradecyltrimethylammonium bromide, or octadecyltrimethylammonium bromide. The method of claim 8, wherein the silicate is sodium silicate. The method of claim 8, wherein the organic salt or inorganic salt which can be combined with the monovalent cation and dissolved in water is LiCl, NaCl, KCl, RbCl, CH ₃ COONa, NaBr, CH ₃ COOK, Na ₂ SO ₄ , NaNO ₃ , NaClO ₄ , NaClO ₃ , sodium ethylenediaminetetraacetic acid, adipic acid disodium salt, 1,3-benzendisulfonic acid disodium salt, or nitrilotriacetic acid Method for producing a medium porous molecular sieve material, characterized in that sodium. 10. The method of claim 8, wherein the firing temperature is between 500 and 600 ° C. 15. A mesoporous molecular sieve material of claim 8, wherein the mesoporous molecular sieve material has a hexagonal arrangement of linearly shaped medium pores having a predetermined size.

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