JPH0345507A - Production of aluminophosphate - Google Patents

Abstract

PURPOSE:To synthesize a high-purity aluminophosphate with excellent crystallinity in a short crystallization time by keeping a reaction mixture composed of a phosphoric acid source, alumina source and ethylpropylamine in a specific composition at a specified temperature. CONSTITUTION:A phosphoric acid source is mixed with an alumina source, water and ethylpropylamine to prepare a reaction mixture having the following composition expressed in terms of molar ratios of oxides. 0.8-1.5 P2O5/Al2O3, 20-100 H2O/Al2O3 and 0.2-0.6 EPA/Al2O3 (EPA indicates C2H5NHC3H7). The resultant reaction mixture is then kept at 110-150 deg.C temperature. Thereby, an aluminophosphate, substantially expressed by the formula Al2O3.1.0+ or -0.2P2O5 based on an anhydrous state and having a powder X-ray diffraction pattern expressed by the table (W, M, S and VS respectively represent weak, medium, strong and very strong) in an uncalcined state is obtained by the above- mentioned method.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention was developed by Mark E.
Davis) et al., and Nature (NAT
URE) Vol. 331, p. 698 (1988), where it was referred to as VP I-5.
ites) Vol. 8, No. 5, pp. 3B2-387 (1988)
Aluminophosphate (hereinafter referred to as VP) whose identification data is shown in
The present invention relates to a method for manufacturing a product (also referred to as I-5). This VPI-5 is expressed by the formula % formula % on an anhydrous basis, taking into account errors associated with measurement conditions, etc., and is substantially powder X as shown in the unfired state.
It can be defined as a substance that has a line diffraction pattern.

Powder X-ray diffraction pattern spacing d (A) Peak intensity 16.44±1
．． 30 VS 8.22±0.32 M 6.18±0.17 W 4.75±0.10 W 4.10±0.07 M 4.06±0.07 M 3.98±0.07 M 3.94±0.07 M 3.77±0.07W-M 3.28±0.04 M 3.08±0.04 W 2.95±0.04W-M 2.74±0.03 W (In the table, W, M, S, and VS represent weak, medium 1 strong, and very strong, respectively.) , :(7) VPI-5 is a unit that forms the skeleton structure using the oxygen tetrahedron of phosphorus and aluminum. It is a molecular sieve having a pore structure with a uniform large pore size of about 12 to 13A, and can reversibly adsorb and desorb molecules smaller than the pore size, and can be used as a catalyst, catalyst carrier, It is useful as an adsorption/separation agent, etc.

<Prior art> Academic conference Q on zeolite synthesis held in Los Angeles in September 1988 (SYMPO8!UN01
J ADVANCES IN ZEOLITE 5YN
Mark E. Davies et al. announced a method for producing VPI-5 using di-n-propylamine or tetrabutylammonium hydroxide as an organic template.

<Problems to be Solved by the Invention> The present invention uses an organic template other than di-n-propylamine and tetrabutylammonium hydroxide to achieve a higher crystallization temperature than those using organic templates, that is, a shorter crystallization period. V with high purity and good crystallinity
The purpose of this study was to provide a method for producing PI-5, and the authors studied conditions such as template concentration, crystallization temperature, and crystallization time.

Means and Effects for Solving the Problems> The present invention provides the following composition by mixing a phosphoric acid source, an alumina source, water and ethylpropylamine, expressed by the molar ratio of oxides, P2O5/A1□030.8 ~1.5 H20/A I203 20~100EPA/A 1
203 0.2-0.6 (EPA is C2I5NH
Represents C3I7.

Hereinafter, the same applies) Prepare a reaction mixture having the following: and heat the reaction mixture at 110℃.
A method for producing an aluminophosphate having the formula % on an anhydrous basis and having a powder X-ray diffraction pattern substantially as shown above in the unfired state, the method comprising: This is a summary.

The present invention will be explained in more detail below.

The phosphoric acid source and the alumina source are not particularly limited, and various phosphorus-containing compounds and various aluminum compounds can be used, respectively. However, it is preferable to use orthophosphoric acid as the phosphoric acid source and aluminum isopropoxide or pseudoboehmite hydrated aluminum oxide as the alumina source. These are used when preparing the reaction mixture.
This is because an aluminophosphoric acid gel with good reactivity can be formed and VPI-5 can be crystallized in a shorter time.

The composition of the reaction mixture should be in the following range in oxide molar ratio:

P 20 s / AI 203 0, 8-1,
5H20/A 1□03 20~100EPA/A1
203 0.2~0. 6 (EPA stands for ethylpropylamine) because P 20 s / A120
If the molar ratio is less than 0.8, VPI-5 can be obtained, but crystalline or amorphous alumina will be produced as an impurity, and if it is greater than 1.5, propylamine phosphate will be produced as a by-product.

If the H20/A 1203 molar ratio is less than 20, a reaction mixture with a suitable viscosity cannot be obtained, making stirring difficult and making it impossible to obtain a homogeneous reaction mixture. Also H2O/Al
When the 2Ox molar ratio is greater than 100, VPI-5 can be obtained, but the yield is low and it is not efficient.

If the E P A / A 1203 molar ratio is smaller than 0.2, aluminophosphate with a structure different from that of VPI-5 will be produced as a by-product, and if it is larger than 0.6, aluminophosphate with a structure different from that of VPI-5 will be produced as a by-product. Salt is produced as a by-product. However, EPA
VPI-5 can also be obtained by replacing a part of with di-n-propylamine or tetrabutylammonium hydroxide, which are already known organic templates for producing VPI-5.

If the reaction mixture is heterogeneous, impurities may be produced as by-products, so it is desirable to add these raw materials with stirring and to stir the final reaction mixture until it becomes substantially homogeneous.

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

Crystallization is carried out under natural pressure by maintaining the temperature at 110°C to 150°C, preferably 120°C to 140°C, until crystals of VPI-5 are formed. If the crystallization temperature is lower than 110°C, crystallization will not proceed.

Moreover, when the temperature is higher than 150°C, aluminophosphate having a structure different from that of VP I-5 is generated. Normally, by leaving it at this temperature for about 2 hours to about 400 degrees, the VPI-5
can be obtained.

After crystallization, it is recovered by conventional separation methods such as filtration or centrifugation, washed and dried to obtain VP I-5 containing a portion of the above ethylpropylamine in its pores.

Even if this ethylpropylamine is present, it does not affect the powder X-ray diffraction pattern, so it can be used as is for measurement. Moreover, the ethylpropylamine in the pores can be decomposed and removed by firing at 350° C. to 700° C., if necessary.

Powder X-ray diffraction herein is referred to as Phillips (Ph
PW1700 powder X-ray diffractometer manufactured by Illps Co., Ltd. Further, CuK-α rays are used as a radiation source, and a variable divergence slit is used to keep the X-ray irradiation area on the δPJ constant sample constant for measurement.

<Effects of the Invention> As shown in the following specific examples, according to the present invention, VPl-5 with high purity and good crystallinity can be produced in a short crystallization time.

<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 A reaction mixture having the following molar composition was prepared by mixing aluminum isopropoxide, orthophosphoric acid, ethyl n-propylamine, and water.

P20s /A1203 1.0 H20/ A I 203 40 E n PA/A 1203 0. 5 (EnPA is C2H,NHn-C,H.

represents. (The same applies hereinafter) This reaction mixture was sealed in an autoclave, heated to 130° C. under natural pressure with constant stirring, and maintained at this temperature for 24 hours to obtain a crystalline product. After filtering this and washing with water,
It was dried at 110°C.

A part of this product was calcined at 600° C. for 2 hours and chemically analyzed, and it was found to be represented by the following formula.

Al2O3.0.98P205 This product was VPI-5 with the powder X-ray diffraction pattern shown in Table 2.

Table 2 d (A) 16, 42 8, 21 6, 18 5, 57 4, 75 4, 10 4, 06 3, 98 3, 95 3, 77 3, 64 3, 28 3, 17 3, 09 3, 03 2,95 2,89 2,74 Relative strength 00 0 0 0 8 8 3 2 5 9 0 1 (%) Table 2 (continued) d (A) Relative strength (%) 2,64 4 2.50 4 2 .35 4 Example 2 In the same manner as in Example 1, a reaction mixture having the following composition was prepared.

P20s/AI203 1. O H20/A 1203 50 EnPA/A I20. 0.5 The reaction mixture was sealed in an autoclave and heated to 130° C. under natural pressure with constant stirring and maintained at this temperature for 48 hours to obtain a crystalline product. After filtering this and washing with water,
It was dried at 110°C.

A part of this product was calcined at 600° C. for 2 hours and chemically analyzed, and it was found to be represented by the following formula.

A 1 2 03 ・0. 99P 205 This product has a powder X-ray diffraction pattern shown in Table 3.
It was PI-5.

d (A) 16, 39 8, 22 6, 18 5, 48 4, 74 4, 10 4, 06 3, 97 3, 94 3, 77 3, 64 3, 59 3, 28 3, 16 Table 3 Relative strength 00 8 2 3 6 8 4 4 0 3 3 (%) Table 3 (continued) d (A) Relative strength (%) 3.08 15 3.03 8 2.95 15 2.90 8 2.74 14 2. 63 4 2, 50 4 2.35 5 Example 3 In the same manner as in Example 1, a reaction mixture having the following composition was prepared.

P205/A 120i 1. 0H20/
A I 20 i 40E n PA/A 12
03 0. 3 This reaction mixture was sealed in an autoclave and heated to 140°C under natural pressure with constant stirring.
This temperature was maintained for 4 hours to obtain a crystalline product. This was filtered, washed with water, and then dried at 110°C.

A part of this product was calcined at 600° C. for 2 hours and chemically analyzed, and it was found to be represented by the following formula.

Al2O,.0.98P20° This product was VPI-5 with the powder X-ray diffraction pattern shown in Table 4.

Table 4 d (A) Relative strength (%) 16.51 100 9.49 2 8.23 30 6.18 16 5.49 4 4.76 18 4.11 35 4.06 48 3.99 22 Table 4 ( (continued) 4 7 4 9 2 9 7 9 4 6 0 4 3 1 5 2 8 1 0 0 3 0 0 2 0 9 Comparative Example I Di-n-propylamine (hereinafter referred to as DP) was used instead of EnPA.
A) is DPA/A l 203 molar ratio 0. The procedure was carried out under the same conditions as in Example 3 except that X in Table 5 was used.
A material with a line diffraction pattern was obtained.

Table 5 d (A) Relative strength (%) 16.31 100 9.62 13 8.19 23 6.87 39 6.49 37 6.17 7 5.52 4 4.88 37 4.72 15 4.24 45 4.09 36 3.96 29 d (A) 3.77 3,60 3,39 3゜ 28 3,16 3,09 3,04 2,95 2,89 2,78 2,73 2,68 2 , 42 2, 36 2, 28 Table 5 (continued) Relative intensity (%) 1 0 9 4 1 0 0 2 7 0 3 5 rVJ in the attribution column in Attribution Table 5 is diffraction by VPI-5, but rHJ Bull, Soc.

F in CheL pp. 1762-177B (1961),
Diffraction of aluminophosphate hydrate, designated H3 by d'Voire. That is, in this example, a considerable amount of 'QH3 was produced as a by-product. This uses di-n-propylamine as the organic template to produce highly pure VPI.
This means that 140°C is too high as a crystallization temperature to produce -5.

In contrast, in the present invention, highly pure VPI-5 can be obtained at a relatively high temperature, that is, in a short period of time.

Claims (1)

[Claims] (1) A phosphoric acid source, an alumina source, water and ethylpropylamine are mixed to form the following composition expressed by the molar ratio of oxides: P_2O_5/Al_2O_3 0.8-1.5H_2
O/Al_2O_3 20-100 EPA/Al_2O_3 0.2-0.6 (EPA stands for C_2H_5NHC_3H_7), and the reaction mixture is maintained at a temperature of 110°C to 150°C. A method for producing an aluminophosphate having the formula Al_2O_3·1.0±0.2P_2O_5 on an anhydrous basis and having a powder X-ray diffraction pattern substantially shown in Table 1 in an unfired state. Table 1 Powder X-ray diffraction pattern spacing d(A) Peak intensity 16.44±1.30 VS 8.22±0.32 M 6.18±0.17 W 4.75±0.10 W 4.10 ±0.07 M 4.06±0.07 M 3.98±0.07 M 3.94±0.07 M 3.77±0.07 W~M 3.28±0.04 M 3.08 ±0.04 W 2.95±0.04 W~M 2.74±0.03 W (In the table, W, M, S, and VS represent weak, medium, strong, and very strong, respectively)