JP4524427B2 - Composition comprising heteropolyacid salt and inorganic oxide and method for producing the same - Google Patents

Description

The present invention relates to a composition comprising a heteropolyacid salt and an aminated or cyanated inorganic oxide, a process for producing the same, and a solid acid catalyst containing the composition.

Currently, liquid acids such as H ₂ SO ₄ , HF, and AlCl ₃ are used as catalysts in many chemical processes. While these liquid acids are effective acid catalysts, they must be separated from the product by neutralization after the reaction. As a result, a large amount of neutralized salt (waste acid) is generated, and enormous energy and cost are required for the treatment. If these processes using a liquid acid catalyst (liquid acid process) can be replaced with a process using a solid acid catalyst (solid acid process), the problem of waste acid treatment can be solved, which is advantageous in terms of cost. Further, from the viewpoint of resource saving, conversion to a solid acid process is desired.

Many acid catalyzed reactions where liquid acids are effective involve water in the reactants or products. So-called ordinary solid acids do not function effectively in the presence of water because their acid sites are poisoned by water (see Non-Patent Document 1).

A small number of solid acid catalysts that work effectively in water have been reported (see Non-Patent Document 1). One of them is H-ZSM-5 zeolite with high Si / Al ratio. This solid acid catalyst is industrially used as an acid catalyst in cyclohexanol synthesis by hydration of cyclohexane (see Non-Patent Document 2). However, H-ZSM-5 has a drawback that it does not work effectively for bulky molecular reactions because its acid sites are present in micropores called micropores of 0.53 nm × 0.56 nm size. (See Non-Patent Document 1). Cation exchange resins such as Nafion-H and Amberist-15 are also known as solid acids that function in water. However, since it is an organic substance, there is a problem in heat resistance. Niobic acid (Nb ₂ O ₅ .nH ₂ O) has been reported to exhibit activity in ester hydrolysis reactions in water (see Non-Patent Document 3). However, its activity is low.

A cesium salt (Cs _2.5 H _0.5 PW ₁₂ O ₄₀ ) of 12-tungstophosphoric acid (H ₃ PW ₁₂ O ₄₀ ), which is a kind of heteropolyacid, is known (see Non-Patent Document 4). It has been reported that this substance is a solid acid catalyst that exhibits a very high catalytic activity for acid-catalyzed reactions in water (see Non-Patent Documents 1 and 5). However, the problem that the catalyst dissolves in water during the reaction has been pointed out, and it cannot be said to be a complete “solid” acid catalyst. In addition, since the primary particles of Cs _2.5 H _0.5 PW ₁₂ O ₄₀ are fine particles of about 13 nm, some of the catalyst particles do not settle after the reaction, the reaction solution becomes suspended, and the catalyst particles are filtered and decanted. There is also a problem that it is difficult to recover. Therefore, without impairing the high acid catalyst activity of Cs _2.5 H _0.5 PW ₁₂ O ₄₀ in water, it is possible to suppress the dissolution in water and obtain the highly settled catalyst particles in order to achieve a solid acid process. It is strongly desired to realize the conversion.

T. Okuhara, Chemical Review, 2002, 102, 3641 H. Ishida, Catalysis Surveys from Japan, 1997, Volume 1, 241 K. Hanaoka, T. Takeuchi, T. Matsuzaki, Y. Sugi, Catalysis Today, 1990, Vol. 8, p. 123 T. Okuhara, H. Watanabe, T. Nishimura, K. Inumaru, M. Misono, Chemistry of Materials, 2000, Vol. 12, p. 2230 M. Kimura, T. Nakato, T. Okuhara, Applied Catalysis A, 1997, 165, 227

The present invention provides a novel heteropolyacid salt composition having a very high acid catalytic activity in water, almost no dissolution in water, and high sedimentation in water, and a method for producing the composition. It is to provide.

The present inventors have intensively studied to solve the above problems. As a result, it has been surprisingly found that the above-mentioned problems can be solved by blending a predetermined heteropoly acid salt and a predetermined inorganic oxide in a predetermined amount, and the present invention has been completed.

That is, the present invention
(1) (A), following formula (II)
[Chemical 1]
Cs _r H _3-r PW ₁₂ O ₄₀ (II)
(Where r is 2 to 3)
95-45 parts by weight of 12-tungstophosphoric acid cesium salt represented by
(B) A composition containing _{5 to} 55 parts by weight of aminated SiO ₂ .

As a preferred embodiment,
(2) The composition according to (1) above, wherein (A) is 93 to 63 parts by weight and (B) is 7 to 37 parts by weight,
(3) The composition according to (1) above, wherein (A) is 88 to 74 parts by weight and (B) is 12 to 26 parts by weight,
( 4 ) a solid acid catalyst comprising the composition according to any one of (1) to ( 3 ) above,
( 5 ) The method for producing the composition according to any one of (1) to ( 3 ) above, wherein (A) and (B) are placed in a solvent and mixed with stirring.
( 6 ) The above wherein the solvent is selected from the group consisting of water, methanol, ethanol, propanol, 2-propanol, butanol, 2-butanol, isobutanol, benzene, toluene, xylene, hexane, heptane, octane and diethyl ether. ( 5 ) The method described can be mentioned.

The present invention provides a novel heteropolyacid salt composition having a very high acid catalyst activity in water, almost no dissolution in water, and a high sedimentation property in water, and a process for producing the composition. provide. By using the composition as a solid acid catalyst, a clean and highly efficient chemical process can be realized, and the cost of the product can be greatly reduced.

Following formula (II)
[Chemical 2 ]
Cs _r H _3-r PW ₁₂ O ₄₀ (II)
(Where r is 2 to 3)
Cs _2.5 H _0.5 PW ₁₂ O ₄₀ is preferably used as the 12-tungstophosphoric acid cesium salt represented by the following formula.

Cesium salt of 12-tungstophosphoric acid is added to an aqueous solution of H ₃ PW ₁₂ O ₄₀ by adding a Cs ₂ CO ₃ aqueous solution so that the Cs / PW ₁₂ O ₄₀ molar ratio is preferably 2 to 3, usually 0 to 50 ° C. It is obtained by stirring and mixing at a temperature of 2 and then evaporating and removing water (Non-patent Documents 1 and 4).

As (B), amino reduction has been SiO ₂ is preferably surface is ized amino.

Amino ized inorganic oxide (B) can be produced as follows. For example, nitrogen, an inert gas atmosphere such as argon, for example, toluene, benzene, xylene, hexane, in a solvent such as heptane, and the inorganic oxide and amination reagent, preferably 0 to 80 ° C. It can be obtained by stirring and mixing at temperature, preferably for 5 minutes to 24 hours. Examples of the aminating reagent, such as 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminobutyl triethoxysilane, 3-aminobutyl trimethoxysilane Ru is used. In addition to the above method, for example, silica and ammonia gas can be treated at 500 to 1000 ° C. for 5 minutes to 24 hours to amination the silica, preferably the silica surface.

In the composition of the present invention, the upper limit of the content (A) is 95 parts by weight, preferably 93 parts by weight, more preferably 88 parts by weight, and the lower limit is 45 parts by weight, preferably 63 parts by weight, more preferably. 74 parts by weight. On the other hand, amino ized inorganic oxide (B) content, the upper limit is 55 parts by weight, preferably 37 parts by weight, more preferably 26 parts by weight, the lower limit is 5 parts by weight, preferably 7 parts by weight, More preferably, it is 12 parts by weight. When the (A) content exceeds the above upper limit and the (B) content is less than the above lower limit, elution of the polyanion into water is inevitable when used as a solid acid catalyst. When the (A) content is less than the above lower limit and the (B) content exceeds the above upper limit, the catalytic activity as a solid acid catalyst is significantly reduced.

The composition of the present invention can be produced by mixing the above (A) and (B) in a solvent and stirring and mixing them . In (A) , usually about 1000 molecules are aggregated to form primary particles having a size of about 13 nm. Therefore, in order to suppress the aggregation of the primary particles, they are dispersed in a solvent and stirred and mixed with (B). It is not manufactured by the so-called dry method. Here, the solvent is not particularly limited as long as it can disperse the cesium salt of heteropoly acid, and for example, water, alcohol, ether, aromatic solvent, saturated hydrocarbon solvent, etc. can be used, preferably , Water, methanol, ethanol, propanol, 2-propanol, butanol, 2-butanol, isobutanol, benzene, toluene, xylene, hexane, heptane, octane, diethyl ether and the like, and water is particularly preferably used. The stirring and mixing is preferably performed at a temperature of the freezing point of the solvent to 80 ° C., preferably for 1 to 60 minutes. The composition obtained by stirring and mixing can be further treated with hydrochloric acid or the like to neutralize amino groups present in the composition. This is preferable because decomposition of the heteropolyacid can be suppressed. Thus the compositions of the present invention produced by the amino ized inorganic oxide (B) and is complexed with (A).

The composition of the present invention can be used as a solid acid catalyst in water preferably as it is or further with a metal supported thereon. For example, hydrolysis reaction of ethyl acetate, 2-methylphenyl acetate, butyl acetate, propyl acetate, methyl acetate, etc., hydration reaction of 2,3-dimethyl-2-butene, cyclohexanol, limonene, octene, etc., acetic acid and ethanol It can be used as a catalyst for the esterification reaction.

In the following examples, the present invention will be described in more detail, but the present invention is not limited to these examples.

(Example)
The obtained Cs _2.5 H _0.5 PW ₁₂ O ₄₀ APTS ⁺ / SiO ₂ composition and heteropolyacid cesium salt (Cs _2.5 H _0.5 PW ₁₂ O ₄₀ ) are powder X-ray diffraction, elemental analysis, IR analysis, pore size distribution It was identified by measurement and measurement of a manipulation electron microscope (SEM) image. Here, APTS ⁺ / SiO ₂ shows the SiO ₂ was aminated as follows.

Powder X-ray diffraction was performed using Miniflex manufactured by Rigaku Corporation. For the measurement, the obtained composition and the powder of cesium salt of heteropoly acid were used as they were. CuKα rays were used for X-rays.

The elemental analysis of carbon and nitrogen was performed using a CHN simultaneous analyzer CHN corder MT-5 manufactured by Yanaco Measurement Co., Ltd. Elemental analysis of phosphorus, cesium, and tungsten was performed using a sequential high frequency plasma emission analyzer ICPS-7000 manufactured by Shimadzu Corporation after dissolving 5 mol of a sample using 1 dm ³ of sulfuric acid.

IR analysis was performed using JASCO FT / IR-230 manufactured by JASCO Corporation. The sample and KBr powder were pulverized and mixed using a mortar at a sample weight: KBr weight = 1: 99, and then molded into a disk shape using a tablet molding machine and subjected to measurement.

The pore size distribution was measured using Belsorp 28 SA manufactured by Nippon Bell Co., Ltd. From the nitrogen adsorption / desorption isotherm measured using this apparatus, the pore diameter was calculated by the DH method.

Measurement of an operation electron microscope (SEM) image was performed using FE-SEM S-4800 manufactured by Hitachi, Ltd.

(Example 1)
Preparation of heteropolyacid cesium salt (Cs _2.5 H _0.5 PW ₁₂ O ₄₀ )
100 grams of H ₃ PW ₁₂ O ₄₀ · nH ₂ O (manufactured by Nippon Inorganic Chemical Industry) was dissolved in 20 ml of pure water. The obtained aqueous solution was transferred to a separatory funnel, 50 ml of diethyl ether was added, and H ₃ PW ₁₂ O ₄₀ · nH ₂ O was extracted from the ether layer. After the ether layer was transferred to an eggplant flask, the ether was evaporated using a rotary evaporator to precipitate H ₃ PW ₁₂ O ₄₀ · nH ₂ O crystals, completing the purification.

The purified H ₃ PW ₁₂ O ₄₀ · nH ₂ O was vacuum-dried at 338K for 4 hours to obtain H ₃ PW ₁₂ O ₄₀ · 6H ₂ O. Next, a 0.08 mol / dm ³ aqueous solution was prepared using the H ₃ PW ₁₂ O ₄₀ · 6H ₂ O. Separately, a 0.1 mol / dm ³ aqueous solution was prepared using Cs ₂ CO ₃ (manufactured by Merck) that was previously vacuum-dried at 473 K for 4 hours.

Ten milliliters of the above H ₃ PW ₁₂ O ₄₀ aqueous solution was collected in an Erlenmeyer flask. While stirring this aqueous solution, 10 ml of the above Cs ₂ CO ₃ aqueous solution was added dropwise at 0.11 ml / min. Here, the Cs / PW ₁₂ O ₄₀ molar ratio is 2.5. After completion of the dropping, stirring was continued for at least 1 hour, and then left overnight. Thereafter, water was evaporated using a rotary evaporator to obtain a white solid.

The obtained white solid was subjected to powder X-ray diffraction, elemental analysis, and IR analysis to confirm that the white solid was Cs _2.5 H _0.5 PW ₁₂ O ₄₀ .

Preparation of the surface was aminated silica (APTS ⁺ / SiO ₂₎ particles
SiO ₂ (Aerosil 50, manufactured by Nippon Aerosil Co., Ltd.) was previously vacuum-dried at 673 K for 24 hours. 1.3 grams of dried SiO ₂ was collected in a 500 ml beaker. Separately, 20 cm ³ of 3-aminopropyltriethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., hereinafter abbreviated as APTS) was dissolved in 200 cm ³ of toluene. 200 cm ³ of the solution was added to the beaker under a nitrogen atmosphere and stirred at room temperature for 2 hours.

The resulting mixture was then filtered using a membrane filter (φ = 0.2 μm), and the resulting solid was vacuum dried at 423K for 12 hours. After drying, about 1.35 grams of the obtained powder was dispersed in 20 cm ³ of water, 6 cm ³ of 6% HCl aqueous solution was further added, and the mixture was stirred for 30 minutes. Thereafter, the solid was filtered using a membrane filter (φ = 0.2 μm), and the collected solid was dried in an oven at 373K. When elemental analysis of the obtained solid was performed, it was confirmed that N and Cl were contained at 0.30 wt% and 0.45 wt%, respectively. Further, when the obtained solid was heated to 500 ° C. or higher in a helium atmosphere, generation of NH ₃ was observed. From these, it was found that the obtained solid was aminated silica.

Preparation of composition (Cs _2.5 H _0.5 PW ₁₂ O ₄₀ ・ APTS ⁺ / SiO ₂ ) of heteropolyacid cesium salt and aminated silica
0.5 grams of APTS ⁺ / SiO ₂ was dispersed in 10 cm ³ of water. Subsequently, 2.83 grams of Cs _2.5 H _0.5 PW ₁₂ O ₄₀ prepared as described above was dispersed in 5 ml of distilled water, and this was added to the suspension in which APTS ⁺ / SiO ₂ was dispersed, and the mixture was stirred at room temperature for 30 minutes. Stir for minutes. Thereafter, the solid was collected by filtration using a membrane filter (φ = 0.2 μm) and dried overnight at room temperature.

The solid obtained as described above was subjected to powder X-ray diffraction, elemental analysis, IR analysis, pore size distribution measurement and operation electron microscope image measurement, and the solid was found to be Cs _2.5 H _0.5 PW ₁₂ O ₄₀ It was confirmed that the composition was APTS ⁺ / SiO ₂ .

FIG. 1 shows Cs _2.5 H _0.5 PW ₁₂ O ₄₀ , the composition obtained in Example 1 (in FIGS. 1 to 4 below, expressed as 85 wt% Cs _2.5 H _0.5 PW ₁₂ O ₄₀ · APTS ⁺ / SiO ₂ ), And X-ray diffraction patterns of APTS ⁺ / SiO ₂ . In FIG. 1, the composition obtained in Example 1 has the characteristic diffraction pattern of Cs _2.5 H _0.5 PW ₁₂ O ₄₀ as it is. Therefore, it was found that the composition was formed in Example 1 while retaining the crystal structure of Cs _2.5 H _0.5 PW ₁₂ O ₄₀ .

FIG. 2 shows IR spectra of Cs _2.5 H _0.5 PW ₁₂ O ₄₀ , the composition obtained in Example 1, and APTS ⁺ / SiO ₂ . In Cs _2.5 H _0.5 PW ₁₂ O ₄₀ , a sharp absorption band attributed to the Keggin structure was observed at 500 to 1300 cm ⁻¹ . In the composition obtained in Example 1, an absorption band attributed to the Keggin structure was observed as in Cs _2.5 H _0.5 PW ₁₂ O ₄₀ . Therefore, it was found that the Keggin structure of Cs _2.5 H _0.5 PW ₁₂ O ₄₀ was retained in the composition obtained in Example 1, and the composition contained Cs _2.5 H _0.5 PW ₁₂ O ₄₀ .

FIG. 3 shows the pore diameter distribution of Cs _2.5 H _0.5 PW ₁₂ O ₄₀ , the composition obtained in Example 1, and APTS ⁺ / SiO ₂ . Cs _2.5 H _0.5 PW ₁₂ O ₄₀ has a hole having a diameter of about 0.5 nm and a hole of about 3 nm. This is because the primary particles (1.3 nm) of Cs _2.5 H _0.5 PW ₁₂ O ₄₀ themselves do not have pores, but when the primary particles aggregate to form secondary particles, the gap between the primary particles and the primary particles When the secondary particles are aggregated to form the tertiary particles, the pore diameter is about 3 nm in the gap between the secondary particles and the secondary particles. This is because a hole is formed (Non-patent Document 1). The composition obtained in Example 1 was found to have pores with the same diameter as Cs _2.5 H _0.5 PW ₁₂ O ₄₀ . However, since the strength of the pores of about 3 nm is low compared to Cs _2.5 H _0.5 PW ₁₂ O ₄₀ , the composition obtained in Example 1 has Cs _2.5 H _0.5 PW on APTS ⁺ / SiO _2. It was found that most of ₁₂ O ₄₀ was present as secondary particles and tertiary particles were partially present.

From the results of elemental analysis, it was found that APTS ⁺ / SiO ₂ contained 0.66 wt% carbon and 0.30 wt% nitrogen. From the nitrogen content (% by weight) and the specific surface area 87 m ² / gram determined from the nitrogen adsorption / desorption isotherm, it was found that the density of amino groups present on the APTS ⁺ / SiO ₂ surface was 1.5 molecules / nm ^2. It was. On the other hand, the surface H ⁺ density calculated from the composition and crystal lattice constant of Cs _2.5 H _0.5 PW ₁₂ O ₄₀ is 1.5 molecules / nm ² . From this, the proton of Cs _2.5 H _0.5 PW ₁₂ O ₄₀ and the amino group present on the surface of APTS ⁺ / SiO ₂ interact with each other in an acid-base manner, and Cs _2.5 H _0.5 PW ₁₂ O ₄₀ particles (about 13 nm) and APTS ⁺ / SiO ₂ . From this, it is considered that Cs _2.5 H _0.5 PW ₁₂ O ₄₀ and APTS ⁺ / SiO ₂ are combined.

FIG. 4 shows an operation electron microscopic image of Cs _2.5 H _0.5 PW ₁₂ O ₄₀ , the composition obtained in Example 1, and APTS ⁺ / SiO ₂ . In the composition obtained in Example 1, it was observed that Cs _2.5 H _0.5 PW ₁₂ O ₄₀ particles (about 13 nm) were complexed on the APTS ⁺ / SiO ₂ surface.

Hydrolysis of ethyl acetate
In a 100 cm ³ glass three-necked flask, 30 cm ^{3 of} 5 wt% aqueous ethyl acetate (ethyl acetate 16.9 mmol, water 1.6 mol) and Cs2.5- (15 wt%) APTS ⁺ / 0.8 grams of SiO ₂ was added. Next, the reaction was carried out at 343 K for 2 hours with stirring to carry out hydrolysis of ethyl acetate. After completion of the reaction, the resulting solution was filtered to recover the filtrate and catalyst. The amount of polyanion eluted in the filtrate was quantified by a calibration curve method using an ultraviolet-visible absorption spectrum (manufactured by Shimadzu Corporation, UVmini 1240). The conversion rate of ethyl acetate is determined by quantifying raw materials and products using FID gas chromatography (Shimadzu GC-14A, manufactured by Shimadzu Corporation) equipped with a packed column (Carbowax 300M column, 2 meters). Asked.

Test for repeated use of catalyst The catalyst recovered after hydrolysis of ethyl acetate as described above was dried overnight at 373K. Using the recovered catalyst, ethyl acetate was hydrolyzed under the same conditions as described above. This operation was repeated twice.

(Example 2)
In the preparation of _{Cs 2.5 H 0.5 PW 12 O 40} · APTS + / SiO 2 composition, except for changing the Cs _2.5 H _0.5 PW ₁₂ O ₄₀ 1.42 grams 2.83 grams is prepared in the same manner as in Example 1, Cs _2.5 An H _0.5 PW ₁₂ O ₄₀ .APTS ⁺ / SiO ₂ composition (hereinafter referred to as Cs2.5- (26 wt%) APTS ⁺ / SiO ₂ ) was obtained. Then, the ethyl acetate was hydrolyzed in the same manner as in Example 1 using the composition as a catalyst.

(Example 3)
In the preparation of _{Cs 2.5 H 0.5 PW 12 O 40} · APTS + / SiO 2 composition, except for changing the Cs _2.5 H _0.5 PW ₁₂ O ₄₀ 0.85 grams 2.83 grams is prepared in the same manner as in Example 1, Cs _2.5 An H _0.5 PW ₁₂ O ₄₀ .APTS ⁺ / SiO ₂ composition (hereinafter referred to as Cs2.5- (37 wt%) APTS ⁺ / SiO ₂ ) was obtained. Then, the ethyl acetate was hydrolyzed in the same manner as in Example 1 using the composition as a catalyst.

(Comparative Example 1)
Cs _2.5 H _0.5 PW ₁₂ O ₄₀ prepared in Example 1 was directly used as a catalyst without forming a composition with APTS ⁺ / SiO _2, and ethyl acetate was hydrolyzed in the same manner as in Example 1. .

(Comparative Example 2)
In the preparation of Cs _2.5 H _0.5 PW ₁₂ O ₄₀ / APTS ⁺ / SiO ₂ composition, except that Cs _2.5 H _0.5 PW ₁₂ O ₄₀ was changed from 2.83 grams to 0.35 grams, it was carried out in the same manner as in Example 1, A Cs _2.5 H _0.5 PW ₁₂ O ₄₀ · APTS ⁺ / SiO ₂ composition (hereinafter referred to as Cs2.5- (59 wt%) APTS ⁺ / SiO ₂ ) was obtained. Then, the ethyl acetate was hydrolyzed in the same manner as in Example 1 using the composition as a catalyst.

(Comparative Example 3)
In the preparation of Cs _2.5 H _0.5 PW ₁₂ O ₄₀ / APTS ⁺ / SiO ₂ composition, except that Cs _2.5 H _0.5 PW ₁₂ O ₄₀ was changed from 2.83 grams to 12 grams, it was carried out in the same manner as in Example 1, A Cs _2.5 H _0.5 PW ₁₂ O ₄₀ · APTS ⁺ / SiO ₂ composition (hereinafter referred to as Cs2.5- (4 wt%) APTS ⁺ / SiO ₂ ) was obtained. Then, the ethyl acetate was hydrolyzed in the same manner as in Example 1 using the composition as a catalyst.

(Comparative Example 4)
APTS ⁺ / SiO ₂ prepared in Example 1 was used as a catalyst without making a composition with Cs _2.5 H _0.5 PW ₁₂ O _40, and ethyl acetate was hydrolyzed in the same manner as in Example 1. .

(Comparative Example 5)
In the preparation of aminated silica particles in Example 1, the same treatment was carried out except that 3-aminopropyltriethoxysilane was not added, and SiO ₂ was not aminated. A composition (hereinafter referred to as Cs2.5-SiO ₂ ) was obtained. Then, the ethyl acetate was hydrolyzed in the same manner as in Example 1 using the composition as a catalyst.

In order to clarify the catalytic effect of the present invention, ethyl acetate was hydrolyzed using a currently known solid acid catalyst in the following comparative examples.

(Comparative Examples 6-7)
As a catalyst, hydrolysis of ethyl acetate was performed in the same manner as in Example 1, using cation exchange resins of Amberist-15 (manufactured by Organo) and Nafion-H (NR-50, manufactured by Du Pont). .

(Comparative Examples 8 to 10)
As catalysts, H-β (Si / Al = 50, manufactured by PQ Corporation), H-ZSM-5 (Si / Al = 36, HSZ-860, manufactured by Tosoh Corporation) and H-mordenite (Si / Al = 5, JRC) -Z-HM10, a catalyst from the Catalytic Society of Japan) was used to carry out the hydrolysis of ethyl acetate in the same manner as in Example 1.

(Comparative Examples 11-15)
As a catalyst, silica alumina (Si / Al = 5.3, JRC-SAL-2, catalyst catalyst reference catalyst), 23 mol% MoO ₃・ ZrO ₂ (L. Li, Y. Yoshinaga, T. Okuhara, Physical Chemistry Chemical Physics, 1999, Vol. 11, p. 4913), 10 mol% WO ₃・ ZrO ₂ (J1443, manufactured by Daiichi Rare Element Chemical Industries), γ-Al ₂ O ₃ (JRC-ALO-1, see Catalysis Society of Japan catalyst) Then, ethyl acetate was hydrolyzed in the same manner as in Example 1 using an oxide or composite oxide of Nb ₂ O ₅ .nH ₂ O (HY-340, manufactured by CBMN).

The results of Examples 1 to 3 and Comparative Examples 1 to 15 are shown in Table 1 below. The results of the repeated use test of the catalyst in Example 1 are shown in Table 2 below.

表中のポリアニオン溶出量は、反応に使用した触媒中のCs_2.5H_0.5PW₁₂O₄₀に対する溶出したCs_2.5H_0.5PW₁₂O₄₀の百分率で示した。

The polyanion elution amount in the table was expressed as a percentage of Cs _2.5 H _0.5 PW ₁₂ O ₄₀ eluted with respect to Cs _2.5 H _0.5 PW ₁₂ O ₄₀ in the catalyst used in the reaction.

Examples 1 to 3 use the catalyst of the present invention. In any case, the conversion rate of hydrolysis of ethyl acetate was good, and the elution of the polyanion was not observed. When the amount of APTS ⁺ / SiO ₂ increases within the range of the present invention, the conversion rate decreases, but the effect of the present invention was not impaired. In addition, as a result of the repeated use test of the catalyst of Example 1, the activity of the catalyst was not decreased and the elution of the polyanion was not observed even after repeated use.

In Comparative Example 1, Cs _2.5 H _0.5 PW ₁₂ O ₄₀ was used as a catalyst as it was. The conversion rate of hydrolysis of ethyl acetate was good, but a large amount of polyanion was eluted. In Comparative Example 2, the amount of APTS ⁺ / SiO ₂ exceeded the scope of the present invention. No hydrolysis of ethyl acetate occurred. In Comparative Example 3, the amount of APTS ⁺ / SiO ₂ is less than the range of the present invention. Although the conversion rate of hydrolysis of ethyl acetate was good, elution of the polyanion could not be prevented. In Comparative Example 4, APTS ⁺ / SiO ₂ was used as a catalyst as it was. The hydrolysis of ethyl acetate did not proceed at all. Comparative Example 5 is a composition with unaminated SiO ₂ . Although the conversion rate of hydrolysis of ethyl acetate was good, elution of the polyanion could not be prevented.

Comparative Examples 6-15 are the results of hydrolyzing ethyl acetate using currently known solid acid catalysts. Comparative Examples 6-7 use a cation exchange resin as a catalyst. In all cases, the conversion was good. However, these have poor heat resistance and have the disadvantage of decomposing when reacted at high temperatures. Comparative Examples 8 to 10 use zeolite as a catalyst. In Comparative Examples 8 and 9, the conversion rate was good. However, as explained below, these catalysts have the disadvantage that they are ineffective for bulky molecular reactions. In Comparative Example 10, hydrolysis of ethyl acetate did not occur. In Comparative Examples 11 to 15, oxides or composite oxides are used as catalysts. In all cases, the conversion rate of hydrolysis of ethyl acetate was low.

In Example 1 above, no elution of polyanions was observed. On the other hand, in Comparative Examples 1 and 5, elution of 5.5% and 3.31% polyanions was observed, respectively. Separately, 1 gram of the composition obtained in Example 1 was added to 100 ml of water and subjected to hot water treatment at 80 ° C. for 4 hours with stirring. There wasn't. On the other hand, when the same hydrothermal treatment was performed on the composition of Comparative Example 5, 4.9% of the polyanion was eluted. From these results, it was confirmed that Cs _2.5 H _0.5 PW ₁₂ O ₄₀ and APTS ⁺ / SiO ₂ were combined in the composition obtained in Example 1.

(Example 4)
Hydration of 2,3-dimethyl-2-butene.
In a 100 cm ³ glass three-necked flask, 3.9 milliliters of 2,3-dimethyl-2-butene (32.8 millimoles), 36.6 milliliters of water, and Cs2.5- (15 wt% prepared in Example 1 as catalyst) ) Put 0.5 grams of APTS ⁺ / SiO ₂ . Next, the reaction was carried out at 343 K for 4 hours with stirring to hydrate the 2,3-dimethyl-2-butene. After completion of the reaction, the resulting solution was filtered to recover the filtrate and catalyst. The amount of polyanion eluted in the filtrate was determined in the same manner as in Example 1. In addition, the conversion of 2,3-dimethyl-2-butene was determined using FID gas chromatography (Shimadzu GC-) equipped with a packed column (PEG 20M 20% Uniport HP 60/80 column, 2 meters). 8A, manufactured by Shimadzu Corporation).

Hydrolysis of 2-methylphenyl acetate.
In a 100 cm ³ glass three-necked flask, 0.59 ml of 2-methylphenylacetate (4 mmol), 60 ml of water, and Cs2.5- (15 wt%) APTS ⁺ / 0.5 grams of SiO ₂ was added. Next, the reaction was carried out at 353 K for 2 hours with stirring, to hydrolyze 2-methylphenyl acetate. After completion of the reaction, the resulting solution was filtered to recover the filtrate and catalyst. The amount of polyanion eluted in the filtrate was determined in the same manner as in Example 1. The conversion rate of 2-methylphenylacetate was measured using FID gas chromatography (Shimadzu GC-14A, Shimadzu Corporation) equipped with a packed column (Thermon 3000 Sincarbon-A column, 1 m) as the raw material and product. Was determined by quantitative determination.

(Comparative Examples 16-18)
As catalysts, Cs _2.5 H _0.5 PW ₁₂ O ₄₀ (same as used in Comparative Example 1), H-ZSM-5 (same as used in Comparative Example 9) and Nb ₂ O ₅ .nH ₂ O, respectively. The hydration of 2,3-dimethyl-2-butene and the hydrolysis of 2-methylphenyl acetate were carried out in the same manner as in Example 4 except that (the same as that used in Comparative Example 15) was used.

The results of Example 4 and Comparative Examples 16 to 18 are shown in Table 3 below.

表3中、水和は2，3‐ジメチル‐2‐ブテンの水和を示し、加水分解は2‐メチルフェニルアセテートの加水分解を示す。

In Table 3, hydration indicates hydration of 2,3-dimethyl-2-butene, and hydrolysis indicates hydrolysis of 2-methylphenyl acetate.

Example 4 uses the catalyst of the present invention. It showed high catalytic activity for both hydration of 2,3-dimethyl-2-butene and hydrolysis of 2-methylphenyl acetate. Moreover, the elution of the polyanion was not seen.

On the other hand, Comparative Example 16 uses Cs _2.5 H _0.5 PW ₁₂ O ₄₀ as a catalyst as it is. Although the catalytic activity was high for all the reactions, a large amount of polyanion was eluted. Comparative Example 17 uses zeolite as a catalyst. In the hydration of 2,3-dimethyl-2-butene, the catalytic activity was lower than in Example 4. In addition, the catalytic activity for bulky molecules such as 2-methylphenyl acetate was remarkably low. Comparative Example 18 uses an oxide as a catalyst. In any reaction, the catalytic activity was extremely low.

The present invention relates to a novel heteropolyacid salt composition having very high acid catalytic activity in water, almost no dissolution in water, and high sedimentation in water, and a process for producing the composition I will provide a. By using the catalyst, a clean and highly efficient chemical process can be realized, and the cost of the product can be greatly reduced. The catalyst is effective in, for example, hydrolysis reaction, hydration reaction, esterification reaction, etc., for example, cyclohexanol synthesis by hydration of cyclohexane, secondary chain by hydration of long chain alkene, for example, 1-octene, etc. It can be used for alcohol synthesis, ethyl methacrylate synthesis by esterification of methacrylic acid and ethanol.

FIG. 1 is an X-ray diffraction chart of Cs _2.5 H _0.5 PW ₁₂ O ₄₀ , the composition obtained in Example 1, and APTS ⁺ / SiO ₂ . FIG. 2 is an IR spectrum chart of Cs _2.5 H _0.5 PW ₁₂ O ₄₀ , the composition obtained in Example 1, and APTS ⁺ / SiO ₂ . FIG. 3 is a pore distribution curve of Cs _2.5 H _0.5 PW ₁₂ O ₄₀ , the composition obtained in Example 1, and APTS ⁺ / SiO ₂ . FIG. 4 is a photograph of the crystal structure of Cs _2.5 H _0.5 PW ₁₂ O ₄₀ , the composition obtained in Example 1, and APTS ⁺ / SiO ₂ .

Claims (3)

(A), following formula (II)
[Chemical 1]
Cs _r H _3-r PW ₁₂ O ₄₀ (II)
(Where r is 2 to 3)
95-45 parts by weight of 12-tungstophosphoric acid cesium salt represented by
(B) A composition comprising _{5 to} 55 parts by weight of aminated SiO2. A solid acid catalyst comprising the composition of claim 1 . The method for producing a composition according to claim 1 , wherein (A) and (B) are mixed in a solvent while stirring.

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