JPH0613460B2 - Method for producing unsaturated carboxylic acid ester - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for producing an unsaturated carboxylic acid ester,
Specifically, it relates to a method for efficiently producing an unsaturated carboxylic acid ester by using a specific catalyst and a solvent in producing the unsaturated carboxylic acid ester from an unsaturated carboxylic acid and an olefin.

[Problems to be Solved by Prior Art and Invention]

Conventionally, various methods have been proposed for producing an unsaturated carboxylic acid ester by reacting an unsaturated carboxylic acid with an olefin. For example, JP-A-61-2499
Japanese Patent Publication No. 49 discloses a method for producing a carboxylic acid ester by reacting a carboxylic acid with an olefin by using a zeolite having outer surface acid points / total acid points ≧ 0.07 as a catalyst. However, in this method, only cyclic or branched olefins can be used, and the yield of carboxylic acid ester is low.

On the other hand, JP-A-57-56045 reports a method for producing a carboxylic acid ester from a carboxylic acid and an olefin using a cation-exchangeable layered clay or a crystalline aluminosilicate as a catalyst. However, in this method, saturated carboxylic acid is used as carboxylic acid, and unsaturated carboxylic acid is not used.

Further, West German Patent No. 2411901 describes a method in which a saturated carboxylic acid and / or its ethyl ester is used as a solvent. However, in this method, since the carboxylic acid ester is obtained by a transesterification reaction, the solvent is consumed. large.

Further, in the above-mentioned conventional technique, since it is necessary to raise the reaction temperature, there is a problem that when an unsaturated carboxylic acid is used, the polymerization reaction thereof simultaneously occurs and the yield of the target product decreases. Further, in a reaction in which a soluble acid (liquid acid) such as sulfuric acid is used as a catalyst, there is a problem in recovery and corrosivity of the catalyst. Therefore, it is desirable to use a solid acid, but in that case, there are drawbacks such as the necessity of using a large excess of olefin and the low production efficiency.

In view of the above situation, the present inventors have conducted extensive studies and studies to develop an efficient production method of unsaturated carboxylic acid ester which is low in cost, high in yield, and easy to separate and purify.

[Means for Solving the Problems]

As a result, in producing an unsaturated carboxylic acid ester from an unsaturated carboxylic acid and an olefin, a crystalline metallosilicate system in which the ratio of silica to metal oxide (eg, alumina, boria, chromia, etc.) as a catalyst is a certain value or more. It was also found that the above object can be achieved by using zeolite and using aromatic hydrocarbons as a solvent. The present invention has been completed based on such findings.

That is, in the present invention, in producing an unsaturated carboxylic acid ester from an unsaturated carboxylic acid and an olefin, Si / M ≧ 6 (atomic ratio) as a catalyst [wherein M is Al, B, F
It is one or more metal atoms selected from e, Zn, Cr, Mn and In. ] The crystalline metallosilicate zeolite of [1] is used, and the aromatic hydrocarbons are used as a solvent.

The reaction that proceeds in the method of the present invention is, for example, RCOOH + H ₂ C═CH ₂ → RCOOC ₂ H ₅ , where R is an unsaturated alkyl group. is there. ] It is represented by a reaction formula like this. That is, this is a reaction in which an olefin is added to a carboxyl group while maintaining the unsaturated property of the unsaturated alkyl group.

In the method of the present invention, there are various unsaturated carboxylic acids that are one of the raw materials, and they may be appropriately selected according to the intended product. For example, acrylic acid, methacrylic acid, crotonic acid, Vinyl acetic acid, 2-pentenoic acid,
Examples thereof include 3-pentenoic acid, 4-pentenoic acid, cinnamic acid, maleic acid and fumaric acid. Among them, acrylic acid produces industrially important products such as ethyl acrylate.

As the olefin which is the other raw material, various ones can be used, for example, ethylene, propylene, 1-butylene, 2-butylene, isobutylene, and various pentenes (1-pentene, 2-pentene, isopentene). Etc.), hexene, heptene, octene, nonene, decene, cyclopentene, cyclohexene, methylcyclopentene, methylcyclohexene and styrene. Especially ethylene, propylene and 1
-Chain-free olefins such as butylene are preferred.

The catalyst used in the present invention has a Si / M (atomic ratio) of 6 or more,
Preferably 6 to 5000, more preferably 10 to 10
00 is a crystalline metallosilicate zeolite. Here, M is Al, B, Fe, Zn, Cr, as described above.
It is one or more metal atoms selected from Mn and In. As M, Al is particularly preferable. For example, there are ZSM-5, ZSM-11 and their proton exchange or various metal ion exchange type zeolites. In addition to the crystalline aluminosilicate zeolite as described above, on condition that the above Si / M ≧ 6 is satisfied,
It is also possible to use a crystalline gallosilicate zeolite, a crystalline galloaluminosilicate zeolite, a crystalline ferroaluminosilicate zeolite, or the like.

Further, in the method of the present invention, it is essential to carry out the reaction in the presence of a solvent, and aromatic hydrocarbons are used as the reaction solvent. Here, as aromatic hydrocarbons, benzene, toluene, xylenes (o-, m-, p-xylene), trimethylbenzene (hemimilitene, pseudocumene, mesitylene), tetramethylbenzene (prenitene, isodulene, durene), ethylbenzene , Diethylbenzene (o-, m-, p-diethylbenzene), ethyltoluene (o-, m-, p-ethyltoluene). Cumene, cymene, naphthalene, methylnaphthalene (α-, β-methylnaphthalene) and dimethylnaphthalene (1,2-; 1,3-; 1,4-; 2,3-dimethylnaphthalene and other 10 isomers) There is.

In the method of the present invention, reaction conditions may be appropriately selected depending on the situation. For example, the reaction temperature is 50 to 300 ° C, preferably 100 to 250 ° C. If the temperature is lower than 50 ° C, the reaction may not proceed sufficiently. If the temperature exceeds 300 ° C, the unsaturated carboxylic acid tends to be easily polymerized and decomposed. The reaction time may be set in the range of 0.01 to 100 hours, preferably 0.1 to 10 hours. Reaction pressure is normal pressure to 20
It is 0 atm, preferably 5 to 150 atm.

In the method of the present invention, the use ratio of the unsaturated carboxylic acid as a raw material and the olefin is not particularly limited and may be appropriately determined depending on the type of raw material used, the type of catalyst or solvent used, the reaction temperature and the like. For example, the molar ratio of unsaturated carboxylic acid and olefin is 1: 1000 to 1000: 1, preferably 1: 100 to 100: 1.

In the method of the present invention, considering that the reaction of unsaturated carboxylic acid and olefin in a ratio of 1: 1 proceeds, the utilization efficiency of the raw material becomes extremely poor outside the above range.

Further, the amount of the crystalline metallosilicate-based zeolite used as the catalyst is a so-called catalytic amount. In particular,
The crystalline metallosilicate zeolite is 0.001 to 10 by weight ratio to the unsaturated carboxylic acid, preferably 0.01 to
It is 1. If it is less than 0.001, the yield of the target unsaturated carboxylic acid ester is extremely low and insufficient, and if it is more than 10, the utilization efficiency of the catalyst is naturally deteriorated.

Further, the amount of the aromatic hydrocarbons used as a solvent is usually 0.01 to 200, preferably 0.1 to 100 by weight ratio to the unsaturated carboxylic acid. If it is lower than 0.01, polymerization tends to occur, and if it is higher than 200, the production efficiency is lowered.

In the method of the present invention, in order to suppress the polymerization reaction of the unsaturated carboxylic acid as the unreacted raw material, the olefin and the unsaturated carboxylic acid ester of the product during the esterification reaction, a polymerization inhibitor is added if necessary. can do.
As the polymerization inhibitor, hydroquinone or the like may be added in a weight ratio of 0.0001 to 0.1 with respect to the unsaturated carboxylic acid.

〔Example〕

Next, the present invention will be described in more detail with reference to Examples and Comparative Examples. In the following Reference Examples, Examples and Comparative Examples, all are closed system pressure reaction vessels with an agitator (autoclave 1
00cc).

Reference Example 1 (Preparation of crystalline aluminosilicate) 1.15 g of sodium aluminate and 30.23 g of 4 tetra-n-propylammonium bromide were dissolved in 140 g of water to prepare a solution A, and 10.95 g of caustic soda was dissolved in 520 g of water. 73.41 g of white carbon (Nipseal LP: manufactured by Nippon Silica Industry Co., Ltd.) was dissolved in the solution to prepare a solution B.

Next, the above-mentioned solutions A and B were mixed at room temperature for 12 minutes, and further stirred for 1 hour to prepare a silica-alumina gel.

The gel was placed in an autoclave and heat-treated at 150 ° C for 48 hours. After cooling, the contents are filtered and washed with water, 120 ° C
And dried for 12 hours. X-ray diffraction analysis of the product confirmed that it was ZSM-5. The obtained ZS
By calcining M-5 at 500 ° C. for 6 hours, 58.2 g of sodium type ZSM-5 was obtained. This sodium type Z
SM-5 was added to a 10-fold amount of 1N ammonium nitrate aqueous solution, and heat treatment was performed at 80 ° C. for 4 hours while stirring.
Then, the mixture was cooled and allowed to stand, and the supernatant was removed by decantation. Furthermore, after repeating the same operation 3 times, the content was filtered, washed with water, and dried at 120 ° C. for 12 hours to obtain ammonium type ZSM-5. This ammonium type ZSM
-5 was baked at 600 ° C. for 6 hours to obtain H-type ZSM-5. An elemental analysis of this product revealed that Si / Al = 4
It was 9 (atomic ratio).

Reference Example 2 (Preparation of Crystalline Aluminosilicate) In the preparation of Reference Example 1, the blending amount of sodium aluminate was changed.
A crystalline aluminosilicate was prepared under the same conditions except that the amount was changed to 3.30 g. Elemental analysis of this product revealed that Si / Al = 32 (atomic ratio).

Reference Example 3 (Preparation of Ti ion-exchange crystalline aluminosilicate) Ammonium type ZSM-obtained in the preparation step of Reference Example 1
10 g of No. 5 was mixed in 100 g of 1N titanium sulfate solution, and heat treatment was performed at 80 ° C. for 4 hours. After cooling, the modified crystalline aluminosilicate obtained is filtered and washed with water to give 120
After being dried at 600C for 12 hours, it was baked at 600 ° C for 6 hours to obtain a Ti ion exchange crystalline aluminosilicate.

Reference Example 4 (Preparation of Fe ion-exchange crystalline aluminosilicate) In Reference Example 3, 1N titanium sulfate solution was changed to 1N iron sulfate (II
I) The same operation was repeated except that the solution was replaced with Fe.
An ion exchange crystalline aluminosilicate was obtained.

Reference Example 5 (Preparation of Cr ion-exchange crystalline aluminosilicate) The same operation was performed except that the 1N titanium sulfate solution was replaced with the 1N chromium (III) sulfate solution in Reference Example 3,
A Cr ion exchange crystalline aluminosilicate was obtained.

Example 1 0.14 mol of acrylic acid, 0.30 mol of ethylene, 0.1 g of hydroquinone in a 100 cc autoclave, 2.0 g of H-type ZSM-5 (Si / Al = 49 (atomic ratio)) prepared in Reference Example 1 as a catalyst, and 10 g of benzene as a solvent. (Weight ratio: acrylic acid / benzene = 1) was added, and the mixture was reacted at 180 ° C. for 2 hours while stirring at 500 rpm. The results are shown in the table.

Example 2 The reaction was performed in the same manner as in Example 1 except that 10 g of pseudocumene (1,2,4-trimethylbenzene) was used as the solvent. The results are shown in the table.

Example 3 H-type ZSM-5 (Si / A) prepared in Reference Example 2 as a catalyst
The reaction was carried out in the same manner as in Example 2 except that 2.0 g (l = 32 (atomic ratio)) was used. The results are shown in the table.

Example 4 Titanium ion exchange-ZS prepared in Reference Example 3 as a catalyst
The reaction was performed in the same manner as in Example 2 except that 2.0 g of M-5 (Si / Al = 49 (atomic ratio)) was used. The results are shown in the table.

Example 5 Iron ion exchange-ZSM-prepared in Reference Example 4 as a catalyst
The reaction was performed in the same manner as in Example 2 except that 2.0 g of 5 (Si / Al = 49 (atomic ratio)) was used. The results are shown in the table.

Example 6 Chromium ion exchange-ZS prepared in Reference Example 5 as a catalyst
The reaction was carried out in the same manner as in Example 2 except that 2.0 g of M-5 (Si / Al = 49 (atomic ratio)) was used. The results are shown in the table.

Comparative Example 1 The reaction was performed in the same manner as in Example 1 except that the solvent was not used. The results are shown in the table.

Comparative Example 2 Except that 10 g of cyclohexane was used as the solvent,
The reaction was carried out in the same manner as in Example 1. The results are shown in the table.

Comparative Example 3 Aside from using 10 g of n-hexane as a solvent,
The reaction was carried out in the same manner as in Example 1. The results are shown in the table.

Comparative Example 4 The reaction was performed in the same manner as in Example 1 except that 10 g of methyl ethyl ketone was used as the solvent. The results are shown in the table.

[Advantages of the Invention] As described above, according to the method of the present invention, by using an aromatic hydrocarbon as a solvent, it is possible to suppress the polymerization during the addition reaction of an olefin, and as a result, an unsaturated carboxylic acid is obtained. The acid ester can be produced in high yield. Further, by using the crystalline metallosilicate-based zeolite which is a solid catalyst, it is possible to enhance the production efficiency of the unsaturated carboxylic acid ester and facilitate separation and purification of the produced unsaturated carboxylic acid ester.

Therefore, according to the method of the present invention, an unsaturated carboxylic acid ester can be industrially advantageously produced at low cost. The unsaturated carboxylic acid ester obtained is
It is effectively used as an industrial raw material for fibers, paints and adhesives.

Claims (3)

[Claims] 1. A method for producing an unsaturated carboxylic acid ester from an unsaturated carboxylic acid and an olefin, wherein Si is used as a catalyst.
/ M ≧ 6 (atomic ratio) [In the formula, M is Al, B, Fe, Z
It is one or more metal atoms selected from n, Cr, Mn and In. ] The crystalline metallosilicate type | system | group zeolite of], and aromatic hydrocarbons are used as a solvent, The manufacturing method of unsaturated carboxylic acid ester characterized by the above-mentioned. 2. The unsaturated carboxylic acid is acrylic acid, methacrylic acid, crotonic acid, vinylacetic acid, 2-pentenoic acid, 3-
At least one compound selected from the group consisting of pentenoic acid, 4-pentenoic acid, cinnamic acid, maleic acid and fumaric acid, wherein the olefin is ethylene, propylene, 1
-Butylene, 2-butylene, isobutylene, pentene,
Hexene, heptene, octene, nonene, decene, cyclopentene, cyclohexene, methylcyclopentene,
The method according to claim 1, which is at least one compound selected from the group consisting of methylcyclohexene and styrene. 3. The aromatic hydrocarbon is selected from the group consisting of benzene, toluene, xylene, trimethylbenzene, tetramethylbenzene, ethylbenzene, diethylbenzene, ethyltoluene, cumene, cymene, naphthalene, methylnaphthalene and dimethylnaphthalene. The method according to claim 1, which is at least one compound.