JPH1043599A - Production of modified meso-pore molecular sieve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To fix metallic ions or ammonium ions in the pores in a meso-pore molecular sieve by an easy operation as well as to remove templates without breaking the porous structure by bringing the molecular sieve into contact with an org. solvent contg. a metallic salt or ammonium salt. SOLUTION: A meso-pore molecular sieve with templates remaining in the pares is brought into contact with an org. solvent contg. a metallic salt or ammonium salt. The org. solvent is preferably a solvent having a low b.p. and high polarity, e.g. an aliphatic alcohol such as methanol, ethanol or propanol having <=100 deg.C b.p. under atmospheric pressure. By the contact, the templates remaining in the pares are removed, metallic ions or ammonium ions are fixed in the pores and the objective modified meso-pore molecular sieve is produced without breaking the porous structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a modified mesopore molecular sieve useful as a catalyst or the like in the fields of chemical and petroleum refining.

[0002]

2. Description of the Related Art A molecular sieve having uniform pores in a mesopore region (mesopore molecular sieve) is obtained by hydrothermal reaction of a silica source or an alumina source-containing silica source with alkyltrimethylammonium as a template [US Pat. No. 5,057,296; No. 5098684]
And kanemite (NaH) which is a kind of layered polysilicate
(Si ₂ O ₅ .3H ₂ O) by ion exchange with alkyltrimethylammonium to convert it into a uniform hexagonal columnar pore structure [Bull. Chem. Soc. Jpn. , 6
3,988 (1990)].

In order to make the mesopore molecular sieve thus obtained useful, it is necessary to remove the template existing in the pores of the mesopore molecular sieve. For this reason, the mesopore molecular sieve is usually heat-treated in an atmosphere of air or an inert gas (such as nitrogen gas) to decompose and remove the template. Since the template and its decomposition products are vaporized and abrupt volume expansion occurs, there is a possibility that a part of the pore structure is broken.

[0004] In order to produce a modified mesopore molecular sieve useful as a catalyst in the fields of chemical and petroleum refining, it is necessary to impart a catalytic function to the mesopore molecular sieve according to the purpose. For example,
By immobilizing various ions in the pores by ion exchange or support, acid-basic or redox properties are imparted to the mesopore molecular sieve. In this case, after decomposing and removing the template existing in the pores by heat treatment,
A complicated method of immobilizing metal ions by ion exchange or support is employed.

[0005] In particular, in order to impart an acid property important as a catalyst to a mesopore molecular sieve, alkali metal ions such as sodium contained in the raw material during the hydrothermal synthesis remain in the mesopore molecular sieve. In many cases, complicated operations are required. That is, after the organic compound was decomposed and removed by the heat treatment, the alkali metal ions in the ammonium nitrate by ion exchange ammonium ions converts the meso pore molecular sieve NH ₄ ⁺ type, ammonia was removed by further firing the H ⁺ type. In addition, there is an inconvenience that the pore structure collapses due to the repetition of such heat treatment.

[0006]

As described above, to produce a modified mesopore molecular sieve by the conventional method, the template is decomposed and removed by heat-treating the mesopore molecular sieve obtained by hydrothermal synthesis. Then, a complicated operation of immobilizing various metal ions or ammonium ions was required. In addition, during the heat treatment, there was a problem that the pore structure of the mesopore molecular sieve was easily broken. The present invention removes the template without breaking the pore structure,
It is an object of the present invention to produce a modified mesopore molecular sieve from a mesopore molecular sieve by immobilizing a metal ion or an ammonium ion by a simple operation.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to contact a mesopore molecular sieve with an organic solvent containing a metal salt or an ammonium salt to remove the template present in the pores and to reduce the fineness. This is achieved by a method for producing a modified mesopore molecular sieve, which comprises immobilizing metal ions or ammonium ions in pores.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
As shown in US Pat. No. 5,057,926, the mesopore molecular sieve used in the present invention is prepared by a hydrothermal reaction from a mixture containing a silica source, an alkali metal source, a template (organic ammonium salt) and optionally an alumina source. 20-100 mm in diameter, easily manufactured by
Is a molecular sieve having uniform pores.

In the production of mesopore molecular sieves, sodium silicate, silicic anhydride, colloidal silica, water glass, fumed silica and the like are used as a silica source. As the alkali metal source, sodium hydroxide,
Potassium hydroxide, sodium silicate, water glass, sodium aluminate and the like are used. As a template, an organic ammonium salt, that is, a hydroxide or halide of an alkyl ammonium having at least one alkyl group having 8 to 36 carbon atoms is used. Therefore, these organic ammonium salts (ie, template) are contained in the pores of the mesopore molecular sieve produced as described above.
Remains. Further, as the alumina source, sodium aluminate, aluminum sulfate, aluminum nitrate, aluminum hydroxide, colloidal alumina and the like are used.

[0010] In the present invention, obtained as described above,
By contacting the mesopore molecular sieve with the template remaining in the pores with an organic solvent containing a metal salt or an ammonium salt, the template present in the pores is removed, and the metal in the pores is removed. The ions or ammonium ions are immobilized. Thus, a modified mesopore molecular sieve (metal ion-modified mesopore molecular sieve, ammonium ion-modified mesopore molecular sieve, hydrogen ion-modified mesopore molecular sieve) can be obtained from the mesopore molecular sieve. In the present invention, the organic solvent containing a metal salt or an ammonium salt may further contain a mineral acid. As the organic solvent, those capable of dissolving a metal salt or an ammonium salt are used, and among them, a solvent having a low boiling point and a large polarity is particularly preferable. Examples of such a solvent include aliphatic alcohols having a boiling point of 100 ° C. or less at atmospheric pressure, such as methanol, ethanol, and propanol. When a mineral acid is contained in the organic solvent, the solvent is preferably a solvent that can simultaneously dissolve the mineral acid.

The metal salt is a metal salt capable of imparting a catalytic function to the mesopore molecular sieve by ion exchange, and may be any metal salt as long as it is soluble in an organic solvent. Among these metal salts, chlorides, nitrates, sulfates and acetates of the metal are preferred.
As such a metal salt, specifically, I-th of the periodic table
Group A elements (Na, K, Rb, Cs, etc.), Group IB elements (Cu, Ag, Au, etc.), Group IIA elements (Mg, Ca,
Sr, Ba, etc.), Group IIB element (Zn, etc.), Group IIIA element (B, Al, Ga, In, etc.), Group IIIB element (S
c, Y, lanthanoids, etc.), Group IVA elements (Sn, Pb
Etc.), Group VA elements (Sb, Bi, etc.), Group VB elements (V, Nb, Ta, etc.), Group VIB elements (Cr, Mo, W)
And the like, halides, nitrates, sulfates, acetates, and the like of Group VIIB elements (Mn, Re, etc.) and Group VIII elements (Fe, Co, Ni, Ru, Rh, Pd, Pt, etc.). . Examples of the ammonium salt include ammonium salts of inorganic acids (such as ammonium nitrate), ammonium salts of hydrogen halide (such as ammonium bromide), and ammonium salts of organic acids (such as ammonium acetate). The amount of the metal salt or ammonium salt contained in the organic solvent is usually 0.1 to 50% by weight, preferably 1 to 10% by weight.

As the mineral acid, hydrochloric acid, nitric acid and sulfuric acid are preferred. The amount of the mineral acid contained in the organic solvent is usually 0.1.
It is 1 to 50% by weight, preferably 1 to 10% by weight.

The contact of the mesopore molecular sieve with an organic solvent containing a metal salt or an ammonium salt may be carried out, for example, by bringing the mesopore molecular sieve into an organic solvent containing a metal salt or an ammonium salt in an amount of 0.01 to 0.01% with respect to the organic solvent.
The immersion is carried out at a ratio of 10 to 10 times by weight, preferably 0.1 to 0.5 times by weight. The temperature (contact temperature) at this time can be in a wide range, but is usually a temperature from 0 ° C. to the boiling point of the organic solvent, preferably a temperature from 20 ° C. to the boiling point of the organic solvent, more preferably an organic solvent. What is necessary is just the boiling point (reflux temperature) of a solvent. The pressure at this time is usually normal pressure. The contact time depends on the contact temperature, and the higher the temperature, the shorter the time can be.However, the above-mentioned contact may be performed for a long time or repeatedly to substantially completely remove the organic compound present in the pores. it can.

The mesopore molecular sieve obtained by the above treatment, in which the template present in the pores is removed and the metal ions or ammonium ions are immobilized in the pores (ie, the modified mesopore molecular sieve), is filtered. After being separated and recovered from an organic solvent containing a metal salt or an ammonium salt by the method described above, it is washed with an organic solvent containing no metal salt or an ammonium salt, and further dried under an atmosphere of air or an inert gas (such as nitrogen gas). This drying is usually performed at 20 to 150 ° C., preferably 100 to 1
At 50C, for 1 to 48 hours, preferably 10 to 24 hours,
Under normal pressure or reduced pressure, air or inert gas (nitrogen gas, etc.)
It is performed under the atmosphere. In the present invention, since the template is removed and only the organic solvent is present as an organic substance in the pores, and the organic solvent does not decompose during the drying process, a rapid volume expansion occurs during the drying and the fineness occurs. The pore structure does not break.

The dried modified mesopore molecular sieve is heat-treated or calcined in an air or nitrogen gas atmosphere to stabilize metal ions in the pores or to convert ammonium ions to hydrogen ions. The heat treatment or baking is usually performed at 200 to 900 ° C., preferably at 30 ° C.
The reaction is performed at 0 to 600 ° C. for 1 to 10 hours, preferably 2 to 4 hours, under normal pressure and in an atmosphere of air or an inert gas (such as nitrogen gas).

[0016]

Next, the present invention will be described specifically with reference to examples.
I do. Reference Example [Production of Mesopore Molecular Sieve]
In a glass container, add tetramethylammonium hydroxide
An aqueous solution and an aqueous sodium silicate solution are added, and n-hexa
Add decyltrimethylammonium bromide solution,
The mixture was stirred at 20 ° C. for about 10 minutes. In addition, tetrame
Tylammonium hydroxide solution is 25% by weight tetra
Methyl ammonium hydroxide (Me_FourNOH) water soluble
37.9 g of liquid (Me_FourNOH: 0.1 mol)
Sodium silicate aqueous solution is sodium silicate nonahydrate (Na_TwoSiO
_Three・ 9H_TwoO) 29.6 g (0.1 mol) in 120 g of water
N-hexadecyltrimethyl alcohol
The aqueous ammonium bromide solution is n-hexadecyltrimethyl
Luammonium bromide (C₁₆H₃₃Me_ThreeNBr) 2
9.2 g (0.008 mol) dissolved in 100 g of water
Was used.

Next, the pH of the mixture was adjusted to 2.0 with 1N sulfuric acid.
And the mixture was subsequently stirred at 20 ° C. for 30 minutes. After completion of the stirring, the mixture (gel) was transferred to a 500 ml Teflon container, and the mixture was placed in an autoclave for 110 minutes.
Hydrothermal synthesis was performed by heating at 24 ° C. for 24 hours. The gel after the reaction is taken out, washed with ion exchanged water, and in air at 110 ° C.
For 12 hours. From the infrared absorption spectrum analysis of the obtained mesopore molecular sieve, it was found that the mesopore molecular sieve contained an organic substance such as a template. The unit lattice length of 45 ° was obtained from the result of the powder X-ray diffraction analysis (FIG. 1), the diffraction peaks of the plane indices 100, 110, 200, and 210 and the d value of the plane index 100.
It was found that a mesopore molecular sieve was formed.

Example 1 [Production of modified mesopore molecular sieve] 1 g of the mesopore molecular sieve obtained in Reference Example was 10% by weight.
10m of ethanol containing titanium tetrachloride (TiCl ₄ )
and heated to reflux for 4 hours. Thereafter, the mesopore molecular sieve was separated by filtration, washed with ethanol, and dried in air at 110 ° C. for 12 hours. In addition, the above operation was performed under normal pressure. According to the infrared absorption spectrum analysis of the obtained modified (titanium-modified) mesopore molecular sieve, this metal-modified mesopore molecular sieve contained only trace amounts of organic substances, and almost all organic substances such as templates were removed. This organic matter is in air, 300
C., easily removed by heat treatment for 1 hour. Also, powder X
X-ray diffraction analysis results (FIG. 2), surface indices 100, 110, 2
Diffraction peaks of 00 and 210 were observed, and it was found that the crystallinity similar to that before modification was maintained even after the template was removed, and no crystal structure was destroyed. As a result of atomic absorption analysis, the atomic ratio of Si to Ti (Si / Ti) was 105.

Example 2 [Production of modified mesopore molecular sieve] A modified mesopore molecular sieve was produced under the same conditions as in Example 1 except that ferric chloride (FeCl ₃ ) was used instead of titanium tetrachloride (TiCl ₄ ). did. From the infrared absorption spectrum analysis of the obtained modified (iron-modified) mesopore molecular sieve,
The modified mesopore molecular sieve contained only trace amounts of organic substances, and almost all organic substances such as templates were removed. This organic matter is in air at 300 ° C,
It was easily removed by heat treatment for one hour. Further, the result of the powder X-ray diffraction analysis (FIG. 3) is the same as that of Example 1, and it can be seen that the crystallinity similar to that before modification is maintained even after the removal of the template, and the crystal structure is not broken. Was. As a result of the atomic absorption analysis, the atomic ratio of Si and Fe (Si /
Fe) was 72.

Example 3 [Production of modified mesopore molecular sieve] A modified mesopore molecular sieve was produced under the same conditions as in Example 1 except that titanium tetrachloride (TiCl ₄ ) was replaced by aluminum chloride (AlCl ₃ ). According to the infrared absorption spectrum analysis of the obtained modified (aluminum-modified) mesopore molecular sieve, the modified mesopore molecular sieve contained only trace amounts of organic substances, and almost all organic substances such as templates were removed. This organic matter was easily removed by heat treatment at 300 ° C. for 1 hour in air.
Further, the result of the powder X-ray diffraction analysis (FIG. 4) is the same as that of Example 1, and it can be seen that the crystallinity similar to that before modification is maintained even after the removal of the template, and the crystal structure is not broken. Was. The results of atomic absorption analysis showed that Si and Al
Was 96 in atomic ratio (Si / Al).

Comparative Example 1 5 g of the mesopore molecular sieve obtained in Reference Example was filled in a vertical quartz reaction tube and heated at 650 ° C. for 4 hours while flowing air. From the infrared absorption spectrum analysis of the obtained mesopore molecular sieve, no organic matter such as a template was found in the mesopore molecular sieve. However, as a result of powder X-ray diffraction analysis (FIG. 5), diffraction peaks with plane indices of 200 and 210 were not recognized, and a part of the pore structure was destroyed by heat treatment for template removal, resulting in poor crystallinity. I knew it was there.

[0022]

According to the present invention, by removing the template without destroying the pore structure, and by immobilizing metal ions or ammonium ions by a simple operation,
Modified mesopore molecular sieves (metal ion-modified mesopore molecular sieves, ammonium ion-modified mesopore molecular sieves, hydrogen ion-modified mesopore molecular sieves) can be easily produced from mesopore molecular sieves. That is, as in the past, the mesopore molecular sieve obtained by hydrothermal synthesis is heat-treated to decompose and remove the template, and then without performing the complicated operation of immobilizing various metal ions or ammonium ions, Further, a modified mesopore molecular sieve can be produced without breaking a part of the pore structure.

[Brief description of the drawings]

FIG. 1 shows a powder X-ray diffraction pattern of a mesopore molecular sieve obtained by hydrothermal synthesis in a reference example.

FIG. 2 shows a powder X-ray diffraction pattern of a modified (titanium ion-modified) mesopore molecular sieve obtained by the method of the present invention in Example 1.

FIG. 3 shows powder X of modified (iron ion-modified) mesopore molecular sieve obtained by the method of the present invention in Example 2.
3 shows a line diffraction pattern.

FIG. 4 shows a powder X-ray diffraction pattern of a modified (aluminum ion-modified) mesopore molecular sieve obtained by the method of the present invention in Example 3.

FIG. 5 shows a powder X-ray diffraction pattern of a mesopore molecular sieve after heat treatment in Comparative Example 1.

Claims (2)

[Claims] 1. Contacting a mesopore molecular sieve with an organic solvent containing a metal salt or an ammonium salt,
While removing the template present in the pores,
A method for producing a modified mesopore molecular sieve, wherein a metal ion or an ammonium ion is immobilized in the pores. 2. The process for producing a modified mesopore molecular sieve according to claim 1, wherein the organic solvent is an aliphatic alcohol having a boiling point of 100 ° C. or less at atmospheric pressure.