JPH03164412A - Crystalline aluminophosphate and its production - Google Patents

Abstract

PURPOSE:To easily produce a crystalline aluminophosphate having specified composition and X-ray diffraction pattern by mixing a phosphate source, an alumina source, water, ethylene glycol and dipropylamine in a specified ratio and holding the mixture at a specified temp. CONSTITUTION:A phosphate source, an alumina source, water, ethylene glycol and dipropylamine are mixed to obtain a reaction mixture. The molar ratios of the constituents of the reaction mixture are P2O5/Al2O3;=0.8 to 1.5, H2O/Al2 O3>=0, EG/Al2O3>=20, (EG+H2O)/Al2O3; 2.0 to 100 and DPA/Al2O3; 0.5 to 20 (EG is HOC2H4OH and DPA is (C3H7)2NH). The reaction mixture is held at 140-200 deg.C for 24-240hr under the autogenous pressure and crystallized. Consequently, a crystalline aluminophosphate having a skeletal structure shown by the chemical formula Al2O3.1.0+ or -0.2P2O5 in the molar ratio of the oxides on a dry basis and having a powder X-ray diffraction pattern shown in the table in the uncalcined state is obtained. The product is useful as the molecular sieve, catalyst, catalyst carrier, separating adsorbent, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION Industrial Application Field The present invention relates to a novel crystalline aluminophosphate and a method for producing the same.

This novel crystalline aluminophosphate is a molecular sieve with phosphorus and aluminum oxygen tetrahedrons forming the 111-position of the skeleton structure, and is useful as a catalyst, catalyst carrier, adsorption/separation agent, etc.

Prior Art> As explained below, the crystalline aluminophosphate of the present invention has the formula Al20i 1 in molar ratio of oxides on an anhydrous basis.
．． It has a skeletal structure with a chemical composition expressed as 0±0.21'205, and a pore structure with a size within the range of 6 to 1OA. The crystalline aluminophosphate corresponding to this is disclosed in Japanese Patent Application Laid-open No. 5
It is disclosed in Japanese Patent Application Laid-open No. 7-77015 and Japanese Patent Application Laid-Open No. 83-89412 under the name of aluminophosphate.

OBJECTS TO BE SOLVED BY THE INVENTION The present invention provides an aluminophosphate having a novel crystalline structure and a method for producing the same, although the oxide molar ratio and pore size are the same as those conventionally known. The purpose is to

Means and Effects for Solving the Problems The crystalline aluminophosphate of the present invention has a skeletal structure with a chemical composition represented by the formula AI203 1.0±0.2P205 in molar ratio of oxide on an anhydrous basis. Moreover, it is characterized in that it substantially has a powder X-ray diffraction pattern shown in Table 1 in an unfired state.

The crystalline aluminophosphate of the present invention is hereinafter referred to as “TAP-16
It is sometimes called ゜.

Table 1 Powder X-ray diffraction pattern spacing d (A) Peak intensity 10.37±0
．． 50M~S5.21±0.12
W4.40±0.09 M4
．． 05±0.07 M3.93±0.0
7V S3.20±0.05
W3, 00±0.04 W2.8
2±0.04 W~M2,55±0.03
W (In the table, W, M, S, and VS represent weak, medium, strong, and very strong, respectively.) This crystalline aluminophosphate has phosphorus and aluminum oxygen tetrahedrons as forming units of the skeletal structure. , diameter 6 from the adsorption of benzene and the above powder X-ray diffraction pattern.
It is recognized that the pore structure has a size within the range of ~IOA.

In addition, the method for producing TAP-16 of the present invention involves mixing a phosphoric acid source, an alumina source, water, ethylene glycol, and dipropylamine to form the following composition in terms of the molar ratio of oxides: P20S/A12 0s 0.8~1
．． 5H20/Al20s Mi OEG/Al
20) Yo20(EG+H20)/A
12 0x 20~100DPA/Alz Oi
O. 5-2.0 (EG is HOC2 Hs
OH represents (Ci Hy ) 2 NH, and DPA represents (Ci Hy )2 NH.

The method consists of preparing a reaction mixture having the same formula (hereinafter the same) and maintaining the reaction mixture at a temperature of 140°C to 200°C to crystallize it.

The phosphoric acid source and 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 isoproboxide or pseudoboehmite Eiwa aluminum oxide as the alumina source.

These raw materials form an aluminophosphoric acid gel with good reactivity during the preparation of the reaction mixture, and can be crystallized in a shorter time.

The composition of the reaction mixture must be in the following range in terms of oxide molar ratio.

P20S/AI2o, 0.8~
1.5H20/A1203
MiOE G/A 120s
Yo20(EC+H20) /A l20s
20~100DPA/A I2o,
o. s ~ 2.0 because P 2 0 s / A
When the I 2 O 3 molar ratio is less than 0.8, TA
Although P-18 is obtained, crystalline alumina is produced as a by-product as an impurity; if it is larger than 1, 5, dibrobylamine phosphate is produced as a by-product.

If the (EG+H,O)/A l 2 0,% ratio is less than 20, it will not be possible to obtain a reaction mixture with a suitable viscosity, making stirring difficult, making it impossible to obtain a homogeneous reaction mixture, and resulting in the formation of impurities. May be greater than 100
18 can be obtained, but the yield per reaction tank is small and not efficient. When the DPA/At20 molar ratio is smaller than 0.5, aluminophosphate with a structure different from that of TAP-16 is produced as a by-product; when it is larger than 2.0, TAP-16 is obtained, but
Crystallization takes an extremely long time.

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 is 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 autogenous pressure by maintaining the temperature at 140°C to 200°C, preferably 160°C to 180°C, until crystals of TAP-18 are formed. If the crystallization temperature is lower than 140'C, crystallization takes a significantly long time. When the temperature is higher than 200"C, aluminophosphate with a different structure from TAP-16 is generated. Usually,
TAP-16 can be obtained by leaving it at the above temperature for about 24 hours to about 240 hours.

After crystallization, the raw material is recovered by conventional separation methods such as filtration or centrifugation, washed, and dried to obtain TAP-1 (i) containing some dipropylamine in its pores. Even if this dipropylamine is /7 r[L, it does not affect the powder X-ray diffraction pattern, so it can be used as is for measurement.

Powder X-ray diffraction of the product in this specification is performed using a powder X-ray diffractometer PV1 manufactured by PIIILIPS.
By 70G. In addition, CuK-α radiation is used as a radiation source,
Using a variable divergence slit, the X-ray irradiation area on the measurement sample is kept constant and J? i decide.

This dipropylamine-containing TAP-16 can be easily decomposed and removed by firing at 350°C to 700''C, if necessary.
The powder X-ray diffraction pattern of -16 was virtually unchanged and T
It can be said that AP-18 has high heat resistance.

Effects of the Invention> As explained above, the crystalline aluminophosphate of the present invention has a novel crystal structure, and is expressed by the formula Al20i 1.0±0.2PzOs in molar ratio of oxides on an anhydrous basis. It has a skeletal structure of chemical composition and a pore structure of a size within the range of 8-1 OA, and according to the production method of the present invention, this crystalline aluminophosphate can be easily produced.

This crystalline aluminophosphate has high heat resistance,
If necessary, a desired catalytically active metal can be supported by impregnation or the like, and it can be usefully used as a catalyst for hydrocarbon conversion or oxidative combustion reactions. Furthermore, by taking advantage of the adsorption characteristics due to the size of the pores, it can be usefully used as an adsorbent, a molecular sieve, and the like.

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 Aluminum isoproboxide, orthophosphoric acid (85%
), di-n-probylamine, and ethylene glycol to prepare a reaction mixture with the following molar composition.

P2 0s /A l 2 0* 1.0H2 0
/ A120s 4.9EG/A1203
30 n-D P A / A 1 2 0 3 1.0
(n-DPA represents (n-C* }f,)2NH.

Below 1. =jJji) This reaction mixture was sealed in an autoclave, heated to 180° C. under autogenous pressure with constant stirring, and maintained at this temperature for 72 hours to obtain a crystalline product. After filtering and washing with water,
It was dried at 110°C.

This raw material was TAP-16 having a powder X-ray diffraction pattern shown in Table 2 and FIG.

A part of this raw material was fired at 600'C for 4 hours and chemically analyzed, and found to have the following composition.

Al20, ・0.99P 2 0 sTable 2 10.37 6,00 5.21 4.84 4.40 4.05 3,94 3.55 3,47 3.20 2.99 2.82 2.55 2,49 2.42 2.38 2,36 2.30 A part of the above raw material was baked at 600° C. for 4 hours. The powder X-ray diffraction pattern of this fired product is shown in Table 3, and was substantially the same as that of the unfired product.

Table 3 10.38 6, OI 5, l9 4.82 4.37 4803 3.93 3.54 3.47 3. l9 3.00 2.89 2,82 Table 3 (continued) d (A) Relative intensity 2.72 1 2.80 1 2.56 14 2.411 5 2.41 3 2.39 3 2.35 4 2 .29 6 2.27 2 (%) Using a standard McBain-Baker adsorption measuring device, the adsorption capacity of n-hexane and benzene was determined after 1 hour at an adsorption temperature of 25°C for this calcined TAP-18. The values shown in Table 4 were obtained.

Since the fired TAP-16 adsorbs benzene with a molecular diameter of about 6A, it has a pore diameter larger than 8A.

Table 4 Molecular diameter Pressure Adsorption amount A Torr wt% nHexane 4.3 22 6.851
8.9 Benzene 5.9 20 8.84
0 L0.9 Tip Example 2 Aluminum isopropoxide, orthophosphoric acid (85%
). G-n-probylamine. and ethylene glycol were mixed to prepare a reaction mixture with the following molar set:

P2 0s /A 12 03 1.0H20/A
1 2 03 4.9EG/A 12 01
30 n-D P A / A I 20 3 1.5 The reaction mixture was sealed in an autoclave and heated to 80° C. under autogenous pressure with constant stirring, and maintained at this temperature for 72 hours to form a crystalline raw material. I got it. After filtering and washing with water, 1
It was dried at 10°C.

This raw material was TAP-18 having the powder XvA diffraction pattern shown in Table 5.

A part of this product was calcined at 600° C. for 4 hours and chemically analyzed, and found to have the following composition.

A I 2 0] ・0.98P,05d (A) 10.38 5.99 5.21 4,86 4,40 4.0B 3,93 3,55 3,47 3,20 3.00 2,82 2,56 2,50 2,43 2.36 2.30 Table 5 (%) The above product was burned under the same conditions as in Example 1, and powder X-ray diffraction and adsorption measurements of the burnt product I did this. The powder X-ray diffraction pattern was substantially the same as that of the unfired product described above, and the adsorption capacity was as shown in Table 6.

Table 6 Molecular diameter Pressure Adsorption amount A Torr wt% nHexane 4.3 22 6.351
8.6 Benzene 5.9 20 8.640
1 (1.7? Example 3 Aluminum isopropoxide, orthophosphoric acid (85%
). A reaction mixture with the following molar composition was prepared by mixing di-n-probylamine, water, and ethylene glycol.

P205/Al■Oi 1.0? 2 0/ A 1 2 03 10
．． 0EC/Al ■ 0, 30n-D
PA/A 12 03 1.0 The reaction mixture was sealed in an autoclave and heated to 180° C. under autogenous pressure with constant stirring and maintained at this temperature for 48 hours lHf to obtain a crystalline product. Filter this. After washing with water, 110
Dry at °C.

The product was TAP-18 with the powder X-ray diffraction pattern shown in Table 4.

A part of this raw product was baked at 600°C for 4 hours and chemically analyzed, and it was found to have the following composition.

A l 2 0 3 ・0.99P205Table 7 10.40G. 01 5,21 4,8B 4,40 4,05 3.94 3.55 3.47 3.20 3,00 2,83 2.55 2.50 2.43 2.39 2.37 2.29 4 BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing the powder X-ray diffraction pattern of unfired TAP-18 obtained in Example 1.

Claims (1)

[Scope of Claims] (1) It has a skeletal structure with a chemical composition represented by the formula Al_2O_3・1.0±0.2P_2O_5 in molar ratio of oxides on an anhydrous basis, and in an unfired state substantially has a structure shown in Table 1 below. A crystalline aluminophosphate having a powder X-ray diffraction pattern shown in FIG. Table 1 Powder X-ray diffraction pattern\Plane spacing d(A)\Peak intensity\10.37±0.50 M~S 5.21±0.12 W 4.40±0.09 M 4.05±0 .07 M 3.93±0.07 VS 3.20±0.05 W 3.00±0.04 W 2.82±0.04 W~M 2.55±0.03 W (In the table, W , M, S, and VS represent weak, medium, strong, and very strong, respectively) (2) Mix a phosphoric acid source, an alumina source, water, ethylene glycol, and dipropylamine, and then Show the following composition, P_2O_5/A1_2O_30.8~1.5H_2O
/A1_2O_3≧0 EG/A1_2O_3≧20 (EG+H_2O)/Al_2O_320~100D
PA/Al_2O_30.5~2.0 (EG is HOC_2H_5OH, DPA is A(C_3
H_7)_2NH) was prepared, and the reaction mixture was heated at 140°C.
The method for producing crystalline aluminophosphate according to claim 1, characterized in that the temperature is maintained at a temperature of from 200°C to 200°C.