JPH01122916A - Crystalline zincosilicate and production thereof - Google Patents

Abstract

PURPOSE:To enable control of acid strength and maintenance of hydrophilicity and obtain the above substance having excellent adsorption and catalyst performances, by mixing a tetramethylammonium ion source, Si source, Al source, Zn source and alkaline (earth) metal or NH4 ion source with water and heating the resultant reaction mixture at a specific molar ratio of oxides. CONSTITUTION:A tetramethylammonium (R) ion source, Al source, Zn source, alkaline (earth) metal or NH4 (M) ion source and Si source, such as water glass or amorphous silica, consisting of hydroxides, halides, sulfates, etc., of respective ions are mixed with water to prepare a reaction mixture in an amount so as to satisfy the following relations. 1-100 ratio of formula I, 0.001-1.0 ration of formula II, 0.015-0.035 ratio (OH<->/H2O), 0-1.0 ratio (M2/nO/SiO2) (n is the valence of M), 10-50 ratio (H2O/SiO2) and 0.01-1.0 ratio of formula III expressed in terms of molar ratios of respective oxides. The resultant reaction mixture is then placed in a hermetically sealed pressure-resistant vessel, kept at 100-250 deg.C temperature for 2hr-10 days and crystallized to afford the aimed substance having a chemical composition of formula IV (0<a<=1; 2-a<=x<=20) based on the anhydrous state and powder X-ray diffraction pattern including spacings in the table.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a novel porous crystalline zincosilicate containing silicon and zinc or these and aluminum, and a method for producing the same. This novel zincosilicate of the present invention is hereafter collectively referred to as "TSZS-11#". Zeolites are generally aluminosilicate, consisting of AtOs,
and has a three-dimensional skeleton structure of S i O4 tetrahedron.

The present invention (7) TSZS-11 has Zn in addition to 5in4
It is a zincosilicate containing O2 tetrahedra or even AlO4 tetrahedra in its three-dimensional skeleton. Since these porous zincosilicate materials have adsorption properties and catalytic performance that cannot be obtained with conventional zeolites, they are useful as molecular sieves, adsorbents, or catalyst components for hydrocarbon conversion reactions.

<Prior art> There are few reports of zeolite-like inorganic crystals containing zinc;
Examples of what is known so far include zinc-aluminum-phosphorus-silicon-oxide molecular sieve (Japanese Patent Application Laid-Open No. 60-231414), aluminophosphate porous material containing zinc (Journal of the
Chemi-cal 5ociety+Ch
chemical communications, 1985
Year.

1056-1057 pages).

<Problems to be Solved by the Invention> The present invention provides a novel crystalline zincosilicate in which part or all of the aluminum in the zeolite skeleton is replaced with zinc, and a method for producing the same.

Means for Solving the Problems> The present inventors have developed a zeolite that has a zeolite structure and contains atoms of different metals in addition to silicon and aluminum in the crystal skeleton, thereby producing fine particles that cannot be obtained with conventional zeolites. The present invention was achieved as a result of intensive research aimed at synthesizing metallosilicates having pore size and solid acid properties, that is, adsorption properties and catalytic performance.

That is, the novel substance of the present invention contains silicon, zinc, or these and aluminum in its crystal skeleton, and expressed in molar ratio of oxides, (1±0.3) M2znO-aZno-(1-a)
A1203.xSiO2 In the formula, a is a number satisfying 0<a≦1, X is a number satisfying (2-a)≦x≦20, M represents at least one kind of cation, and n represents the valence of M. ) is a porous crystalline zincosilicate having a chemical composition on an anhydrous basis, and having a powder X-ray diffraction pattern substantially including the interplanar spacings shown in Table 1 in an unfired state.

Table 1 Powder X-ray diffraction pattern O Kannu 11 6.36±0.15 M 4.49±0.10 W~M 3.67=1-0.10 VS3.17±0.
10 W 2.84±0.10 W 2.59±0.08 W (In the table, W, M, and VS are weak and medium, respectively.

Represents very strong. ) The cation M is not particularly limited, but is a cation such as a tetramethylammonium ion, an alkali metal ion, an alkaline earth metal ion, an ammonium ion, a hydrogen ion, or a mixture of these cations.

In addition, the method of the present invention includes a silicon source; a zinc source; an aluminum source; a tetramethylammonium ion source; any one or more of alkali metal ions, alkaline earth metal ions, and ammonium ion sources; and water; The following composition Sio2/ (A1203+Zn0) 1~100 ZnO/ (A1203+Zn0) 0.001~1.0 0H-/H200,015~0.035M''2/n・O
/51020~1.0 H20/S i 02 10~50 TMA"/ (S i 02+A I 203+ Z
n O) 0.01 to 1.0 (However, M' is any one or more of alkali metal ions, alkaline earth metal ions, and ammonium ion sources, n' is the valence of M', and TMA" is tetra (representing methylammonium ion) is prepared by SIl, and this reaction mixture is
This is a method for producing TSZS-11 characterized by maintaining the temperature at about 100°C to about 250°C.

Silicon source, zinc source, aluminum source, tetramethylammonium ion source, alkali metal ion.

The source of alkaline earth metal ions or ammonium ions is not particularly limited. For example, as an alkali metal ion, alkaline earth metal ion or ammonium ion source,
A neutral salt containing the ion or a hydroxide of this ion and the ion can be used.

As the silicon source, water glass, colloidal silica, amorphous silica, fumed silica, etc., which are conventionally used in zeolite production, can be used. Sources of zinc include
Zinc chloride, zinc sulfate, zinc phosphate, etc. can be used. Aluminum sources include alumina sol, pseudoboehmite, sodium aluminate, aluminum hydroxide, and released aluminum, which are conventionally used in the production of zeolite and olide.

Aluminum sulfate etc. are used. A source of tetramethylammonium ion is supplied by introducing its hydroxide or halide.

If the reaction mixture is heterogeneous, impurities may be generated as by-products, so these raw materials are added under stirring, and the intermediate mixture until all of the raw materials are added and the final reaction mixture after the supply is substantially free. It is preferable to stir until the mixture becomes homogeneous.

The final reaction mixture thus obtained is crystallized in a sealed pressure vessel made of stainless steel lined with an inert plastic material, such as polytetrafluoroethylene, to prevent contamination with impurities.

The crystallization temperature should be between 100°C and 250°C. This is because crystallization takes a long time at temperatures below 100°C.
At temperatures exceeding 250° C., crystallization progresses in a short time, but impurities are likely to be generated.

Although pressure may be applied during crystallization, it is preferable to carry out under natural pressure.

The final reaction mixture is crystallized by holding under the above conditions, usually for about 2 hours to about 10 days, and the product is recovered by conventional separation methods such as filtration or centrifugation.

TSZS-11 thus obtained contains tetramethylammonium ions used as a mineralizer in its pores. This tetramethylammonium ion can be removed if necessary, but it cannot be removed by treatments such as ion exchange, and the
It is removed by firing at a temperature of 50-650°C.

CuKa radiation was used for X-ray diffraction of the product.

As is known to those skilled in the art, the determination of the parameter 2θ is subject to human and mechanical errors, which can impose an error of approximately 0.4° on each recorded value of 2θ. Furthermore, the recorded values of 2θ and peak intensity may vary depending on the composition of the skeleton of the substance, the type of cations, the degree of moisture absorption, etc.

This error is, of course, the d-spacing calculated from each recorded value,
and gives uncertainty to the value of relative intensity. However, this uncertainty is not sufficient to prevent the novel materials of the present invention from being distinguished from prior art materials.

<Effect of the invention> TSZ containing the above tetramethylammonium ion
In S-11, the tetramethylammonium ion is decomposed and removed by firing at 450 to 650°C in an air stream as necessary, and then converted to ammonia form by ion exchange with ammonium salts such as ammonium hydroxide, ammonium sulfate, and ammonium nitrate. After that, 450-650
Ammonia is removed by calcination at ℃, and the active hydrogen type T is
It can be made into SZS-11.

This hydrogen type TSZS-11 has ZnO/(
By changing the molar ratio of A1203+Zn0), the acid strength can be changed continuously.

Even in conventional aluminosilicate, Si in the crystal
Although it is possible to control the acid strength by changing the molar ratio of 02/A I 203, aluminosilicate
It is known that as the i 02/A 1203 molar ratio increases, its hydrophilicity decreases. however,
TSZS-11 of the present invention makes it possible to control acid strength and maintain its hydrophilicity, which could not be achieved with conventional aluminosilicate. By controlling , the selectivity of the reaction can be favorably influenced.

TSZS-11 is produced by ordinary ion exchange, impregnation, etc.
It supports desired metal ions and can be used as a catalyst component.

<Examples> In order to explain the present invention more specifically, Examples are shown below, but the present invention is not limited to the following Examples.

Example 1 1.05 g of zinc chloride and amorphous silica (S i 02 = 8
7.7wt%, A 1203:0. +5wt%, H20
= 11.8 wt%) was mixed with 68°36 g of water. To the resulting slurry, add 6.67 g of sodium hydroxide (98% NaOH) to 45.57 g of water.
A solution of sodium hydroxide was added, and finally 2.71 g of tetramethylammonium chloride was added to prepare a reaction mixture having the following composition.

5102/(A1203+Zn0)=23ZnO/(A
1203+Zn0) =0.920H-/H20=0
．． 023 Na20/S io2 =0.40 H20/S i 02 =35 TMA”/ (S i02+Al2O3+Zno)=0
．． 38 (TMA+: tetramethylammonium ion.

same as below. ) This reaction mixture was sealed in an autoclave and heated under natural pressure for 1
Heating to 70°C and holding this temperature for 68 hours gave a crystalline product. This was filtered, washed with water, and then dried at 110°C.

Chemical analysis revealed that this product had the following molar composition.

0.31 (T MA) 20 φ0.87N a 2
0 ・0.95Zn Oφ0.05A l 203 ・
8.3S i O2 Also, this is X shown in Table 2 and Figure 1
The zincosilicate of the present invention had a line diffraction pattern.

Table 2 Wataru-Jin A'-・ 6.362 50 4.493 33 3.676 100 3.168 11 2.840 15 2.594 21 Example 2 A reaction having the following composition was conducted in the same manner as in Example 1. A mixture was prepared.

SiO2/(A1203+Zn0-) =42.82
nO/(A1203+Zn0) =0.860H-/
H20=0.017 Na20/SiO2=0.30 H20/5IO2=25 TMA◆/ (S i 02+A l 203+ Z
n 0 )=0.39 This reaction mixture was sealed in an autoclave, heated to 170° C. under natural pressure with constant stirring, and maintained at this temperature for 68 hours to obtain a crystalline product. After filtering and washing with water, 11
It was dried at 0°C.

Chemical analysis revealed that this product had the following molar composition.

” 0.22 (TMA)20 ・0.93N a20
・0.902n 0 ・0.10A 120 a
-17.2S i O2 This was also the zincosilicate of the present invention having the X-ray diffraction pattern shown in Table 3.

Table 3 Wataru-Ll->-・ 6.362 56 4.493 48 3.670 100 3.173 15 2.840 17 2.592 23 Example 3 A reaction having the following composition in the same manner as in Example 1 A mixture was prepared.

5jO2/(A120g-1-ZnO) =23Zn
O/(A1203+Zn0) =0.920H-/H
20=0.032 Na20/S i02 =0.40 H20/5i02 Tomi25 TMA”/ (S i02+A12o3+Zno)=0
．． 38 The reaction mixture was sealed in an autoclave, heated to 160° C. under natural pressure with constant stirring, and maintained at this temperature for 68 hours to obtain a crystalline product. After filtering and washing with water, 11
It was dried at 0°C.

Chemical analysis revealed that this product had the following molar composition.

0.17 (TMA) 20-0.89N a 20
-0.932n O・0.07A l 203 ・7.
2S i O2 This was also the zincosilicate of the present invention with the X-ray diffraction pattern shown in Table 4.

Table 4 Wataru-IAj-・ 6.362 65 4.493 39 3.663 100 3.171 15 2.838 20 2.589 23 Example 4 Same as Example 1 except that aluminum chloride was added at the same time as zinc chloride. A reaction mixture having the following composition was prepared in a similar manner.

S i02/(A1203+Zn0)=25ZnO/(
A1203+Zn0) =0.500H-/H20=
0.023 Na20/S j02 =0.40 H20/SiO2=35 TMA meeting/ (SiO2+AlzO3+Zn0)
=0.40 This reaction mixture was sealed in an autoclave, heated to 170° C. under natural pressure with constant stirring, and maintained at this temperature for 68 hours to obtain a crystalline product. After filtering and washing with water, 11
It was dried at 0°C.

Chemical analysis revealed that this product had the following molar composition.

0.17 (TMA) 20-0.89N a 20
-0.372n O・0.63A 1203・9.4
S i O2 was also a zincosilicate of the present invention with the X-ray diffraction pattern shown in Table 5.

Table 5 Mu” Yu ・ 6.344 45 4.488 36 3.657 100 3.164 12 2.835 13 2.587 17

[Brief explanation of the drawing]

Figure 1 shows the zincosilicate powder X obtained in Example 1.
It is a figure showing a line diffraction pattern.

Claims (1)

[Claims] (1) Contains silicon, zinc, or both and aluminum in the crystal skeleton, expressed as an oxide molar ratio, (1±0.3)
M_2_/_nO・aZnO・(1-a)Al_2O_
3.xSiO_2 (where a is a number satisfying 0<a≦1, x is a number satisfying (2-a)≦x≦20, M represents at least one kind of cation, and n represents the valence of M. ) A porous crystalline zincosilicate having a chemical composition on an anhydrous basis, and having a powder X-ray diffraction pattern substantially including the interplanar spacings shown in Table 1 in an unfired state. Table 1 Powder X-ray diffraction pattern\Spacing d(A)\Peak intensity\ 6.36±0.15M 4.49±0.10W~M 3.67±0.10VS 3.17±0.10W 2 .84±0.10W 2.59±0.08W (In the table, W, M, and VS represent weak, medium, and very strong, respectively.) (2) Tetramethylammonium ion source; silicon source; aluminum source; zinc source; any one or more of alkali metal ion, alkaline earth metal ion, and ammonium ion source; and water are mixed to form the following composition SiO_2/(Al_2O_3+ZnO) 1 to 100, expressed in molar ratio of oxides. ZnO/(Al_2O_3+ZnO) 0.001~1.0 OH^-/H_2O0.015~0.035M'_2_
/_n・O/SiO_20~1.0H_2O/SiO_
210~50 R/(SiO_2+Al_2O_3+ZnO)0.01
~1.0 (However, M' represents any one or more of an alkali metal ion, an alkaline earth metal ion, and an ammonium ion, n' represents the valence of M', and TMA^+ represents a tetramethylammonium ion. ) is prepared, and the reaction mixture is divided into 100
A method for producing porous crystalline zincosilicate, which comprises maintaining the temperature at a temperature of 0.degree. C. to 250.degree.