JPH0812320A - Production of crystalline silicoalumino phosphate - Google Patents

Abstract

PURPOSE:To safely produce a crystalline silicoalumino phosphate in large quantities. CONSTITUTION:In this production method of the crystalline silicoalumino phosphate, alcohol or a water-alcohol mixed solvent is used as a solvent in the stages of (A)-(C). (A) The stage in which aluminum compd. and phosphorus compd. are mixed. (B) The stage in which silicon compd. is mixed with the mixture obtained in the stage (A). (C) The stage in which an org. templating agent is mixed with the mixture obtained in the stage (B).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing crystalline silicoaluminophosphate (hereinafter referred to as SAPO).

[0002]

2. Description of the Related Art As a method for producing SAPO, which is preferably used as various catalysts and adsorbents that require heat resistance and hot water resistance, there is a method disclosed in Japanese Patent Publication No. 3-201010. This method generally comprises the following steps: (a) Aluminum compounds such as aluminum alkoxide, hydrated aluminum oxide and sodium aluminate, and orthophosphoric acid, phosphorous acid, diphosphite dioxide, and diphosphorus pentaoxide. And a phosphorus compound such as are mixed with water as a solvent. (B) An aqueous dispersion of a silicon compound such as silicon oxide is added to the above mixed solution. (C) An aqueous solution of an organic templating agent is added to the mixture obtained in (b) above. (D) heating the mixed solution obtained in (c) in a pressure vessel,
Hydrothermally synthesized under autogenous pressure. Water is used as a solvent in all of these steps.

[0003]

However, when water is used as a solvent, a uniform mixture may not be obtained when the aluminum compound and the phosphorus compound are mixed, for example. Therefore, a compound having a desired composition cannot be obtained in high purity in many cases.

A further problem is that, for example, when an aluminum alkoxide, which is preferably used as a substance that easily reacts uniformly with a phosphorus compound, is used, when the aluminum alkoxide is brought into contact with the phosphorus compound, the aluminum alkoxide is decomposed. A fever is intense. Therefore, even a small amount of reaction scale is in a dangerous state, and it is very difficult to synthesize SAPO in a large amount and safely. Therefore, SAPO can be manufactured safely in large quantities.
Development of a practical method is desired.

[0005]

DISCLOSURE OF THE INVENTION In view of these problems, the present inventors have earnestly studied and improved, and as a result, produce a crystalline silicoaluminophosphate in a large amount and safely at one time. Succeeded in developing the method and completed the present invention.

That is, the present invention is: (1) In the following steps (A) to (C),
(C) A method for producing a crystalline silicoaluminophosphate, which comprises using an alcohol or a water-alcohol mixed solvent as a solvent for all the steps or any of the steps (A) to (C), ) Step of mixing aluminum compound and phosphorus compound (B) Step of mixing silicon compound with the mixture obtained in (A) above (C) Mixing organic templating agent with the mixture obtained in (B) above Step (2) In the step (A) described in (1) above, the production method described in (1) above, wherein alcohol or a water-alcohol mixed solvent is used as a solvent, (3) the aluminum compound is an aluminum alkoxide, and phosphorus The production method according to (1) or (2) above, wherein the compound is orthophosphoric acid or metaphosphoric acid.

Next, the present invention will be described. In the present invention, an organic templating agent is used. This organic templating agent is deeply involved in determining the crystal structure of SAPO.

Specific examples of the organic template agent that can be used include tetraethylammonium hydride, tetramethylammonium ion, tetraethylammonium ion, tetrapropylammonium ion, tetrabutylammonium ion, di-n-propylamine,
Triethylamine, triethanolamine, piperidine, cyclohexylamine, N, N-diethylethanolamine, dicyclohexylamine, N, N-dimethylethanolamine, choline, N, N'-dimethylpiperazine, 1,4-diazabicyclo- [2,2 , 2] Octane, N-methyldiethanolamine, N-methylethanolamine, N-methylpiperidine, 3-methylpiperidine, N-methylcyclohexylamine, 3-methylpyridine, 4-methylpyridine, quinuclidine, N, N ′.
-Dimethyl-1,4-diazabicyclo- [2,2,2]
Octane ion, di-n-butylamine, neopentylamine, ethylenediamine, pyrrolidine, 2-imidazolidone and the like can be mentioned. One kind or several kinds of organic templating agents can be used at the same time. The amount of the organic templating agent used is preferably 0.03 to 0.81 mol per mol of the aluminum compound.

As the aluminum compound, a known compound can be used, but preferably a compound which proceeds uniformly when reacted with a phosphorus compound, for example, pseudoboehmite, aluminum trimethoxide, aluminum triethoxide, aluminum Mention may be made of aluminum alkoxides and aluminophosphates such as tri-2-butoxide, aluminum tri-t-butoxide, aluminum triisopropoxide. Of these, aluminum triisopropoxide is particularly preferable in view of availability and controllability of reaction.

As the phosphorus compound, orthophosphoric acid, metaphosphoric acid, phosphorous acid, potassium dihydrogen phosphate, sodium dihydrogen phosphate, monoammonium phosphate and aluminophosphate are preferable, and orthophosphoric acid is particularly preferable. The amount of the phosphorus compound used is preferably 0.45 to 0.67 mol per mol of the aluminum compound.

As the silicon compound, known raw materials such as fused silica, silica sol, silica gel, silica alkoxide and the like can be mentioned, with preference given to silica sol and silica gel. The amount of the silicon compound used is preferably 0.033 to 0.67 mol with respect to 1 mol of the aluminum compound.

As the solvent, alcohol or a mixed solvent of water and alcohol is used, but water-soluble alcohol is preferable, and examples of such alcohol include methanol, ethanol, n-propyl alcohol, i-propyl alcohol, butanol and pen. Examples include tanol and phenol. Of these, particularly preferred are methanol, ethanol, n-propyl alcohol and i-propyl alcohol, which are miscible with water in an unlimited amount. These alcohols are most preferably used in the above step (A), may be removed by distillation after the step (A) is completed, or may be present as they are in the reaction solution as a solvent in the steps (B) to (C). It doesn't matter what you do. The amount of alcohol used is usually 100 to 5000 ml, preferably 20 per 1 mol of aluminum contained in the aluminum compound.
It is 0 to 4000 ml.

Although the phosphorus compound, silicon compound and organic templating agent used in the present invention often contain water, an excessive amount of water lowers the pH of the reaction solution and inhibits crystal growth and the like. . In particular, the presence of an excessive amount of water in the step (A) is not preferable because there is a risk of boiling due to heat generation of the reaction. Therefore, the amount of alcohol used in the present invention is 10 to 200 with respect to 100 parts by weight of water contained in the reaction mixture in steps (A) to (C).
It is adjusted so as to be 20 parts by weight, preferably 20 to 100 parts by weight.

In the present invention, first, an aluminum compound and a phosphorus compound are used as a solvent for an alcohol (when water is contained in the phosphorus compound, an alcohol-water mixed solvent is used).
Mix using. Rapid mixing at this time also causes heat generation and is not preferable. For example, when the amounts of the aluminum compound and phosphorus compound used are on the 50 mmol scale, it is preferable that the mixing time be 10 seconds or more. The reaction is preferably carried out at a temperature as low as possible, particularly preferably 40 ° C. or lower. Then, a silicon compound and an organic templating agent are sequentially added to and mixed with this reaction mixture.

The pH at this time is as high as p
H gives better results. The pH of this mixture is 9
The above is preferable, and 11 or more is particularly preferable.

The mixed solution obtained as described above is heated in a pressure vessel and hydrothermally synthesized under autogenous pressure to obtain an organic templating agent-containing SAPO. The heating temperature at this time is preferably 150 ° C. or higher and 300 ° C. or lower, and particularly 2
The temperature is preferably 00 ° C or higher and 300 ° C or lower. Reaction time is 5 to 1
20 hours is preferred.

When the organic template-containing SAPO is used, for example, as a catalyst, it is generally used after firing to remove the organic template-forming agent. The firing temperature is preferably 400 ° C. or higher and 700 ° C. or lower, and the firing time is preferably 2 to 10 hours.

In the present invention, by using an alcohol which does not cause a rapid reaction with the reaction raw material, it is possible to react under a high pH condition and suppress generation of reaction heat. As a result, there is an advantage that a large amount of target products can be safely synthesized.

[0019]

EXAMPLES Next, the present invention will be described in more detail with reference to Examples and Comparative Examples. However, the present invention is not limited to the following examples.

Example 1 10.2 g of aluminum triisopropoxide was weighed in a beaker and 50 ml of isopropyl alcohol was added,
It was stirred. Further, 4.9 g of 85 wt% orthophosphoric acid was weighed in another beaker, and 25 ml of isopropyl alcohol was added to the solution of the aluminum compound. Further, 75 ml of isopropyl alcohol was added and stirring was continued.

After 20 hours, the solvent in the beaker was distilled off using an oil bath at 90 ° C., 180 ml of water was added and the mixture was stirred, and a 30% aqueous dispersion of silicon oxide (CATALOID-
SI-30, manufactured by Catalysts & Chemicals Industry Co., Ltd.) (1.5 g) was added and stirring was continued. After 30 minutes, 29.4 g of 10% tetraethylammonium hydroxide aqueous solution was added. The solution was placed in a zirconia-coated stainless steel pressure vessel and
41 under autogenous pressure (20-21kg / cm ² ) at 0 ° C
The mixture was heated and stirred for a time to react.

After the reaction was completed, the reaction mixture was rapidly cooled and the solid reaction product in the container was recovered by centrifugation at 1500 rpm. Pure water was added to this for the purpose of washing, and the mixture was stirred, and then centrifuged at 1500 rpm, which was carried out 4 times, and then dried to obtain the product 5.6.
g was obtained. X-ray diffraction measurement of this product (RIGAKU
RINT-1100V), the diffraction pattern shown in Table 1 was obtained. This was almost the same as the diffraction pattern of SAPO-34 disclosed in Example 32 of JP-B-3-72010.

[0023]

[Table 1] Table 1 Peak No. 2θ d I / I ₀ × 100 1 9.46 9.34 100 2 12.78 6.9 2 12 3 3 14.02 6.31 12 4 15.94 5.56 54 5 17.94 94.94 18 6 18 .84 4.70 9 7 20.50 4.33 92 8 21.48 4.13 1 9 22.12 4.02 8 10 23.00 3.86 5 11 25.20 3.53 34 12 25.76 3.46 19 13 26.58 3.35 18 14 27.50 3.24 4 15 28.16 3.17 6 16 29.46 3.03 5 17 30.44 2.93 329 29 18 31.18 2. 87 21 19 32.26 2.77 3 20 33.86 2.65 3 21 34.28 2.61 6 22 35.94 2.50 6 23 36.22 2.48 5 24 38.70 2.32 2 25 39.60 2.27 3

In Table 1, θ: diffraction angle (degree) of Kα ray of Cu d: interplanar spacing (angstrom) I: intensity of each peak I ₀ : intensity of the strongest peak

Example 2 A beaker was charged with 10.2 g of 85 wt% orthophosphoric acid,
50 ml of methanol was added thereto and stirred. 10.2 g of aluminum triisopropoxide was added little by little thereto, 50 ml of methanol was further added, and stirring was continued for 6 hours. Next, the solvent was distilled off using an oil bath at 90 ° C., and 1.8 g of a 30 wt% aqueous solution of silica sol and 29.4 g of a 10% tetraethylammonium hydroxide solution were added thereto.

This solution was then placed in a zirconia-coated stainless steel pressure vessel and heated at 210 ° C. under autogenous pressure (20-21 kg / cm ² ) for 38 hours. After the reaction is completed, it is rapidly cooled to remove the solid reaction product in the vessel to 1
It was recovered by centrifugation at 500 rpm. Pure water was added to this for the purpose of washing, and the step of centrifuging at 1500 rpm was carried out 4 times and then dried to obtain 5.5 g of a product. X-ray diffraction measurement of this product was performed. As a result, a diffraction pattern similar to that of Example 1 was obtained.

Example 3 A beaker was charged with 10.2 g of 85 wt% orthophosphoric acid,
25 ml of methanol was added thereto and stirred. 10.2 g of aluminum triisopropoxide was added thereto little by little, and stirring was continued for 6 hours. And 1.5 g of silica sol and 29.4 g of 10% tetraethylammonium hydroxide solution.
Was added.

This solution was then placed in a zirconia-coated stainless steel pressure vessel and heated at 210 ° C. under autogenous pressure (20-21 kg / cm ² ) for 41 hours. After the reaction is heated, it is cooled rapidly, and the solid reaction product in the vessel is reduced to 1
It was recovered by centrifugation at 500 rpm. Pure water was added to this for the purpose of washing, and the step of centrifuging at 1500 rpm was carried out 4 times and then dried to obtain 5.5 g of a product. X-ray diffraction measurement of this product was performed. As a result, a diffraction pattern similar to that of Example 1 was obtained.

Comparative Example 1 An attempt was made to prepare SAPO-34 according to the method described in Example 35 of Japanese Patent Publication No. 3-72010 mentioned above. That is, 85 wt% orthophosphoric acid 46.1 in a beaker
105 g of water was added to g and stirred. Next, 81.7 g of aluminum triisopropoxide was added little by little to mix with the phosphoric acid aqueous solution. However, during the addition, the decomposition reaction suddenly started and the solution boiled, and part of the mixture burst out of the system. For this reason, it was forced to stop this supplementary examination from the viewpoint of ensuring safety.

Comparative Example 2 Since a runaway reaction occurred in Comparative Example 1, the order of mixing the aluminum compound and the phosphorus compound was reversed. That is, 81.7 g of aluminum triisopropoxide was added to 55 m of water.
It was dissolved in 1 and stirred. An aqueous solution prepared by dissolving 85 wt% orthophosphoric acid in 40 ml of water was added dropwise thereto over 10 minutes. Further, the container was washed with 10 ml of water. This solution was stirred for 1 hour, and 6 g of a 30 wt% aqueous solution of silica sol was added. After stirring for an additional 1 hour, 36.8 g of 10% tetraethylammonium hydroxide solution was added.

This solution was then placed in a zirconia-coated stainless steel pressure vessel and heated at 210 ° C. under autogenous pressure (20-21 kg / cm ² ) for 38 hours. After the reaction is completed, the mixture is rapidly cooled to remove the solid reaction product in the container by 15
It was recovered by centrifugation at 00 rpm. 4 steps of adding pure water to this and centrifuging at 1500 rpm
I went there. The product was dried and subjected to X-ray diffraction measurement.
As a result, the diffraction pattern (SAPO-5) disclosed in Example 1 of Japanese Patent Publication No. 3-72010 and the diffraction pattern (SAP of Example 35 disclosed in the same) are disclosed.
It became a mixed diffraction pattern with O-34).

[0032]

EFFECTS OF THE INVENTION According to the present invention, by using alcohol as a solvent, it is possible to synthesize pure SAPO at a low cost and in a large amount of reactions at one time with high safety, without significantly changing the apparatus. You can

Claims (3)

[Claims] 1. In the following steps (A) to (C),
Production of crystalline silicoaluminophosphate, characterized in that an alcohol or a water-alcohol mixed solvent is used as a solvent in all of the steps (A) to (C) or in any of the steps (A) to (C). Method. (A) a step of mixing an aluminum compound and a phosphorus compound (B) a step of mixing a silicon compound with the mixture obtained in (A) above, and (C) an organic templating agent obtained in (B) above Mixing process 2. The production method according to claim 1, wherein in the step (A) according to claim 1, alcohol or a water-alcohol mixed solvent is used as a solvent. 3. The method according to claim 1, wherein the aluminum compound is an aluminum alkoxide and the phosphorus compound is orthophosphoric acid or metaphosphoric acid.