JPH08143502A - Production of hydroxyalkanal - Google Patents

Abstract

PURPOSE: To obtain a hydroxyalkanal in a high selectivity and in a high yield by hydrating an unsaturated aldehyde in an aqueous solution in the presence of a carboxylic acid and a metal-carrying ion exchange resin as a catalyst. CONSTITUTION: An unsaturated aldehyde of the formula (R is H, 1-5C hydrocarbon) is hydrated in the presence of a catalyst in an aqueous solution to obtain a hydroxyalkanal. Therein, an ion exchange resin carrying a metal (especially preferably lead) is used as the catalyst, and a carboxylic acid is added to the reaction system. The carboxylic acid is added in an amount of 0.01-10wt.% based on the unsaturated aldehyde. The carboxylic acid is preferably a polybasic carboxylic acid, especially oxalic acid. The unsaturated aldehyde is preferably acrolein. The method can achieve the profitable improvement in the conversion of the unsaturated aldehyde in a short time. The highly concentrated unsaturated aldehyde aqueccus solution can be used to obtain the hydroxyalkanal in a high selectivity and in a high yield.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a hydroxyalkanal by hydrating an unsaturated aldehyde in an aqueous solution in the presence of a catalyst.

[0002]

2. Description of the Related Art Conventionally, for example, 3-hydroxypropanal (3-hydroxypropionaldehyde), which is a kind of hydroxyalkanal, is obtained by hydrating acrolein, which is a kind of unsaturated aldehyde, in an aqueous solution in the presence of a catalyst.
Various manufacturing methods as shown below are known as methods for obtaining

That is, US Pat. No. 2,434,110 discloses a method of using a mineral acid such as sulfuric acid as an acidic homogeneous catalyst in the above reaction system. However, this method has a drawback that the selectivity of 3-hydroxypropanal is low and the 3-hydroxypropanal cannot be efficiently produced. Further, it is difficult to separate the homogeneous catalyst from 3-hydroxypropanal and to reuse the catalyst.

Therefore, as a method for solving the above drawbacks and improving the selectivity of 3-hydroxypropanal, US Pat. No. 3,536,763 discloses a method of using an acidic ion exchange resin as an acidic heterogeneous catalyst in the above reaction system. Is disclosed. Japanese Patent Laid-Open No. 3-135932 (German Patent No. 3926136.0
Japanese Patent Laid-Open No. 4-300844 (German Patent No. 4038192.7) discloses a method of using an ion exchange resin having a phosphon group, an amino group, or an aminophosphon group as an acidic heterogeneous catalyst in the above reaction system. . Japanese Unexamined Patent Publication No. 5-194291 (US Pat. No. 735,391) discloses a method of using an alumina-bonded zeolite as an acidic heterogeneous catalyst in the above reaction system. JP-A-5-221912 (German Patent No. 413
No. 8982.4) discloses a method of using TiO ₂ supporting phosphoric acid as an acidic heterogeneous catalyst in the above reaction system. Further, Japanese Patent Laid-Open No. 5-279285 (German Patent No. 413898
No. 1.6) discloses a method of carrying out the above reaction using a buffer solution containing a carboxylic acid and a tertiary amine in the presence of an acidic catalyst.

In these methods, the concentration of the raw material acrolein in the aqueous solution is low (about 20% by weight).
Less than 3), the selectivity to 3-hydroxypropanal is good, and therefore 3-hydroxypropanal is obtained with high selectivity.

[0006]

However, according to the study by the inventors of the present invention, in the above conventional method, when the acrolein concentration is high (about 20% by weight or more), that is, it is industrially advantageous. When a high-concentration aqueous acrolein solution is reacted, 3-hydroxypropanal, which is a reaction product, has an aldehyde group, so that a sequential reaction (side reaction) of the 3-hydroxypropanal actively occurs. I understand. That is, a decrease in selectivity from acrolein to 3-hydroxypropanal is seen, and therefore
It has a drawback that the selectivity of the 3-hydroxypropanal is lowered. Further, the metal-supported acidic heterogeneous catalyst used in the above conventional method, although the detailed cause is not clear, the reaction rate of the hydration reaction is slow, therefore, in a short time industrially advantageous It has the drawback of low conversion of acrolein. Therefore, the above-mentioned conventional production method has a low conversion rate of acrolein, and since it is not possible to increase the concentration of acrolein in the aqueous solution to improve the productivity of 3-hydroxypropanal, it is satisfactory from an industrial viewpoint. It turned out not to be the method of obtaining.

The object of the present invention is to solve the above-mentioned problems and to improve the conversion rate of unsaturated aldehyde in a short time, which is industrially advantageous, and to prepare a high-concentration unsaturated aldehyde aqueous solution. It is to provide a production method capable of producing hydroxyalkanal with a high selectivity and a high yield even when used.

[0008]

Means for Solving the Problems The inventors of the present invention have made earnest studies on a method for producing a hydroxyalkanal by hydrating an unsaturated aldehyde in an aqueous solution in the presence of a catalyst, and as a result, found that a metal-supported ion By using an exchange resin as the catalyst and adding a carboxylic acid to the reaction system, the reaction rate of the hydration reaction is increased, and moreover, the selectivity from unsaturated aldehyde to hydroxyalkanal and hydroxyalkane are obtained. It has been found that the yield of canal is improved. That is, using a metal-supported ion exchange resin, and by adding a carboxylic acid to the reaction system, it is possible to improve the conversion rate of unsaturated aldehyde in a short time industrially advantageous, and The inventors have found that hydroxyalkanal can be obtained with high selectivity and high yield by using a highly concentrated unsaturated aldehyde aqueous solution, and have completed the present invention.

That is, in order to solve the above-mentioned problems, the method for producing hydroxyalkanal according to the first aspect of the present invention has the general formula (I)

[0010]

Embedded image

(In the formula, R represents a hydrogen atom or a carbon number of 1 to
In the method of producing a hydroxyalkanal by hydrating an unsaturated aldehyde represented by 5) in an aqueous solution in the presence of a catalyst, a metal-supported ion exchange resin is used as the catalyst. When used, it is characterized by adding a carboxylic acid to the above reaction system.

In order to solve the above-mentioned problems, the method for producing hydroxyalkanal according to the second aspect of the present invention is the method for producing hydroxyalkanal according to the first aspect, wherein the addition amount of the carboxylic acid to the unsaturated aldehyde is ,
It is characterized by being in the range of 0.01% by weight to 10% by weight.

In order to solve the above-mentioned problems, the method for producing a hydroxyalkanal according to the third aspect of the present invention is the method for producing a hydroxyalkanal according to the first or second aspect, wherein the carboxylic acid is a polyvalent carboxylic acid. It is characterized by being.

In order to solve the above-mentioned problems, the method for producing a hydroxyalkanal according to claim 4 is the method for producing a hydroxyalkanal according to claim 1, 2 or 3, wherein the carboxylic acid is oxalic acid. It is characterized by being.

In order to solve the above-mentioned problems, the method for producing a hydroxyalkanal according to the fifth aspect of the present invention is the method for producing a hydroxyalkanal according to the first, second, third or fourth aspect, wherein the metal is lead. It is characterized by being.

In order to solve the above-mentioned problems, the method for producing a hydroxyalkanal according to the sixth aspect of the present invention is the method for producing a hydroxyalkanal according to the first, second, third, fourth or fifth aspect. The aldehyde is acrolein.

The present invention will be described in detail below. The unsaturated aldehyde (2-alkenal) represented by the general formula (I) used as a raw material in the present invention is not particularly limited, but in the formula, the substituent represented by R is a hydrogen atom or a carbon atom. It is composed of a hydrocarbon group of the numbers 1 to 5, and the hydrocarbon group is a methyl group, an ethyl group, a propyl group, a butyl group, or an amyl group. As the above-mentioned unsaturated aldehyde, specifically, for example, acrolein,
Methacrolein, 2-formyl-1-butene, 2-formyl-
1-pentene, 2-formyl-1-hexene, 2-formyl-1-
Heptene etc. are mentioned. And of these unsaturated aldehydes, acrolein is preferred.

According to the method of the present invention, the corresponding 2-hydroxyalkanal or 3-hydroxyalkanal can be selectively obtained from these unsaturated aldehydes. That is, in the general formula (I), 3-hydroxypropanal (3-hydroxypropionaldehyde), which is 3-hydroxyalkanal, is selectively obtained from acrolein in which the substituent represented by R is a hydrogen atom. On the other hand, R
2-Hydroxyalkanal is selectively obtained from an unsaturated aldehyde in which the substituent represented by is a hydrocarbon group. The 3-hydroxypropanal obtained when acrolein is used as the unsaturated aldehyde is important as an industrial raw material for producing 1,3-propanediol.

The concentration of the unsaturated aldehyde in the aqueous solution (hereinafter simply referred to as "concentration") depends on the solubility of the unsaturated aldehyde in water, the reaction temperature, etc., but is preferably in the range of 5% by weight to the saturated concentration. The range of 50 wt% to 50 wt% is more preferable, the range of 20 wt% to 50 wt% is more preferable, and the range of 25 wt% to 40 wt% is most preferable. When the concentration of unsaturated aldehyde is lower than 5% by weight, the production efficiency of hydroxyalkanal is lowered, which is not preferable. Further, if the concentration of the unsaturated aldehyde is higher than the saturated concentration, a polymerization reaction of the unsaturated aldehyde which does not dissolve occurs and the selectivity for hydroxyalkanal is lowered, which is not preferable.

The catalyst used in the present invention includes
Ion exchange resins loaded with metal are preferred. The above ion exchange resin is not particularly limited as long as it is an ion exchange resin that can be suitably used for the hydration reaction of unsaturated aldehydes. The metal supported on the ion exchange resin is not particularly limited, but lead is particularly preferable. The amount of the ion exchange resin used with respect to the unsaturated aldehyde is not particularly limited, and may be appropriately set depending on, for example, the types of the unsaturated aldehyde and the ion exchange resin. The method for preparing the ion exchange resin is not particularly limited.

The amount of metal supported on the ion exchange resin is
Depending on the composition of the ion exchange resin, 0.001% by weight to 10%
The content is preferably in the range of wt%, more preferably in the range of 0.01 wt% to 5 wt%, still more preferably in the range of 0.01 wt% to 1 wt%. If the amount of supported metal is less than 0.001% by weight, the effect of supporting the metal on the ion exchange resin will not be sufficiently exhibited, which is not preferable. On the other hand, if the amount of supported metal is more than 10% by weight, the yield of hydroxyalkanal is lowered, which is not preferable.

The method of supporting the metal on the ion exchange resin is not particularly limited, and a generally practiced method can be adopted. To support the metal on the ion exchange resin, specifically, for example, when the metal is lead, lead nitrate, dip the ion exchange resin in an aqueous solution in which a predetermined amount of a lead compound such as lead acetate is dissolved, This can be achieved by stirring under predetermined conditions to cause cation exchange, taking out the ion exchange resin by filtration and washing with water.

The supporting as used herein may be in any form such as salt, chelate, adsorption, clathrate and the like. Also, the supported lead is
It may be either an ion or a metal. Moreover, examples of the form of the ions include oxides, halides, and sulfides.

The carboxylic acid added to the reaction system in the present invention is not particularly limited, but a monovalent carboxylic acid or a polyvalent carboxylic acid can be used. Specific examples of the above-mentioned carboxylic acid include formic acid, acetic acid, monovalent carboxylic acids such as (meth) acrylic acid, and divalent carboxylic acids such as oxalic acid, but polyvalent carboxylic acids are preferable. Particularly preferred are divalent carboxylic acids such as oxalic acid.

The amount of the carboxylic acid added to the unsaturated aldehyde depends on the type of the unsaturated aldehyde or the carboxylic acid, but is preferably within the range of 0.01% to 10% by weight.
More preferably in the range of 5% by weight to 0.01% by weight
It is more preferably in the range of 3 wt%. If the addition amount of the carboxylic acid is less than 0.01% by weight, the effect of adding the carboxylic acid is not sufficiently exhibited, which is not preferable. Further, if the amount of carboxylic acid added is more than 10% by weight, the yield of hydroxyalkanal decreases, which is not preferable.

The reaction temperature is not particularly limited, but is preferably 50 ° C to 250 ° C, for example, when acrolein is used as the unsaturated aldehyde, 50 ° C to 140 ° C.
C is preferred. If the reaction temperature is less than 50 ° C, the reaction rate will be slow and the hydration reaction will take time, which is not economical, and if the reaction temperature exceeds 250 ° C, polymerization of unsaturated aldehyde, etc. It is not preferable because a side reaction occurs and the yield of hydroxyalkanal is lowered.

The present invention may be carried out in any of a batch system, a semi-batch system and a continuous system, but the reaction system is preferably a closed system. The reaction pressure when the reaction system is a closed system is not particularly limited,
1kg / cm ² ~20kg / cm ² is preferred. In addition, even when the reaction is carried out at a temperature lower than the boiling point of the unsaturated aldehyde, the reaction system should have a 1
It is preferable to apply a kg / cm ² ~5kg / cm ² about the reaction pressure. The reaction pressure may be applied, for example, by filling the reaction container with a gas inert to the reaction system (for example, N ₂ gas or He gas). Regarding the reaction pressure, the higher the pressure, the more the amount of unsaturated aldehyde dissolved in water increases, and the yield of hydroxyalkanal increases. On the other hand, the pressure-resistant structure of the reactor must be made stronger, There are disadvantages such as an increase in size. Therefore, the reaction pressure is
It may be set in consideration of the balance between the two.

After the completion of the reaction, a target aqueous solution of hydroxyalkanal can be easily obtained by a simple separation operation such as filtration or distillation. Also, hydroxyalkanals can be easily isolated, if desired. Then, for example, taking 3-hydroxyalkanal as the hydroxyalkanal as an example, 3-hydroxyalkanal may actually exist as a hemiacetal form and an acetal form in an aqueous solution. However, they can be easily converted to 3-hydroxyalkanals. Further, hydroxyalkanal may exist as a hemiacetal form and an acetal form of the corresponding alcohol even in the presence of alcohols, but these can be easily converted into hydroxyalkanal.

The recovered water, the ion-exchange resin as a catalyst, the carboxylic acid, and the unreacted unsaturated aldehyde can be repeatedly used for the hydration reaction.

[0030]

According to the above method, the reaction rate of the hydration reaction is increased by using the ion-exchange resin supporting the metal as the catalyst and adding the carboxylic acid to the reaction system, and the unsaturated The selectivity from aldehyde to hydroxyalkanal and the yield of hydroxyalkanal can be improved. That is, using a metal-supported ion exchange resin, and by adding a carboxylic acid to the reaction system, it is possible to improve the conversion rate of unsaturated aldehyde in a short time industrially advantageous, and Since a highly concentrated unsaturated aldehyde aqueous solution can be reacted, the productivity of hydroxyalkanal can be improved.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto. The conversion of unsaturated aldehyde represented by the general formula (I) and the selectivity of hydroxyalkanal are defined as follows.

Unsaturated aldehyde conversion (%) = (moles of unsaturated aldehyde consumed / moles of unsaturated aldehyde fed) × 100 hydroxyalkanal selectivity (%) = (to hydroxyalkanal Number of moles of unsaturated aldehyde converted / number of moles of unsaturated aldehyde consumed) × 100 Selectivity of hydroxyalkanal dimer (%) = (number of moles of unsaturated aldehyde converted to hydroxyalkanal dimer) / Mol of unsaturated aldehyde consumed) x 1
00 Unsaturated aldehyde, hydroxyalkanal, and hydroxyalkanal dimer can be quantified by a known method such as gas chromatography (GC), but in the present invention, they were measured by gas chromatography.

[0033]

【Example】

Example 1 A predetermined amount of water was placed in a reaction vessel equipped with a thermometer and a stirrer, and then a predetermined amount of acrolein as an unsaturated aldehyde was charged so that the concentration in the aqueous solution would be 17% by weight. Next, a predetermined amount of a lead-supported ion exchange resin was added to the above aqueous solution as a catalyst, and 2.5% by weight of oxalic acid as a carboxylic acid was added to acrolein. As the above ion exchange resin, Duolite (trade name (Duolite), REM &
Haas Co. (Rohm & Haas Co.) was used. The amount of lead supported on the ion exchange resin was adjusted to a predetermined value of 5% by weight or less.

The above reaction solution was stirred at 60 ° C. for 2 hours.
Acrolein was hydrated by reacting for a time.
After completion of the reaction, the reaction solution was filtered, and the filtrate was analyzed by a predetermined method. As a result, the conversion rate of acrolein was 53% and the selectivity of 3-hydroxypropanal was 85%.
The selectivity of 3-hydroxypropanal dimer was 13%, and the selectivity as hydroxyalkanal was 98%, which is the sum of the selectivity of both.

An aqueous solution containing 8.1% by weight of 3-hydroxypropanal obtained by the hydration reaction and 1.3% by weight of a 3-hydroxypropanal dimer was prepared. And
A known Raney nickel catalyst was added to this aqueous solution to hydrogenate 3-hydroxypropanal and a 3-hydroxypropanal dimer. The reaction conditions are hydrogen pressure of 100 kg.
/ cm ² , the reaction temperature was 60 ° C, and the reaction time was 6 hours. After completion of the reaction, the aqueous solution was analyzed and as a result, production of 1,3-propanediol corresponding to the total amount of 3-hydroxypropanal and 3-hydroxypropanal dimer was confirmed. That is, 1,3-propanediol was quantitatively produced.
From this, it was found that the 3-hydroxypropanal dimer was converted to 1,3-propanediol by a conventionally known hydrogenation.

Example 2 Example 1 was repeated except that the concentration of acrolein as the unsaturated aldehyde in Example 1 was changed from 17% by weight to 29% by weight and the reaction time was changed to 3 hours.
The same reaction and analysis were performed. As a result, the conversion rate of acrolein was 65%, the selectivity of 3-hydroxypropanal was 40%, and the selectivity of 3-hydroxypropanal dimer was 14%. Was 54%.

Comparative Example 1 The same reaction and analysis as in Example 1 were carried out except that oxalic acid as the carboxylic acid in Example 1 was not used. As a result, the conversion rate of acrolein is
55%, the selectivity of 3-hydroxypropanal is 79%, and the selectivity of 3-hydroxypropanal dimer is 10%.
%, The combined selectivity of both was 89%, the conversion of acrolein was low, and a large amount of a product was produced by the sequential reaction of 3-hydroxypropanal.

As is clear from these results, according to the method of the present example, by using the ion-exchange resin carrying lead as a catalyst and adding oxalic acid to the reaction system, It is possible to improve the conversion rate of acrolein in an advantageous short time, and since the successive reaction of the reaction product 3-hydroxypropanal is suppressed, even when using a high-concentration acrolein aqueous solution. , 3-Hydroxypropanal could be obtained with high selectivity and high yield.

[0039]

As described above, the method for producing a hydroxyalkanal according to claim 1 of the present invention has the general formula (I):

[0040]

Embedded image

(In the formula, R represents a hydrogen atom or a carbon number of 1 to
In the method of producing a hydroxyalkanal by hydrating an unsaturated aldehyde represented by 5) in an aqueous solution in the presence of a catalyst, a metal-supported ion exchange resin is used as the catalyst. When used, it is a method of adding a carboxylic acid to the above reaction system.

As described above, the method for producing a hydroxyalkanal according to claim 2 of the present invention is a method in which the addition amount of the carboxylic acid to the unsaturated aldehyde is in the range of 0.01% by weight to 10% by weight. Is.

As described above, the method for producing a hydroxyalkanal according to claim 3 of the present invention is a method in which the carboxylic acid is a polyvalent carboxylic acid.

As described above, the method for producing a hydroxyalkanal according to claim 4 of the present invention is a method in which the carboxylic acid is oxalic acid.

As described above, the method for producing a hydroxyalkanal according to claim 5 of the present invention is a method in which the metal is lead.

The method for producing a hydroxyalkanal according to claim 6 of the present invention is, as described above, a method in which the unsaturated aldehyde is acrolein.

According to the above method, the reaction rate of the hydration reaction is increased by using the ion-exchange resin supporting the metal as the catalyst and adding the carboxylic acid to the reaction system, and the reaction formation Since the successive reaction (side reaction) of the product hydroxyalkanal is suppressed, hydroxyalkanal can be produced with high selectivity and high yield even when a highly concentrated unsaturated aldehyde aqueous solution is used. . That is, it is possible to improve the conversion rate of unsaturated aldehyde in a short time, which is industrially advantageous, and it is possible to react a high-concentration unsaturated aldehyde aqueous solution, so that the productivity of hydroxyalkanal is improved. be able to. Therefore, the above method has an effect of being preferably used as a method for producing hydroxyalkanal.

Claims (6)

[Claims] 1. A compound represented by the general formula (I): (Wherein R represents a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms) is hydrated in an aqueous solution in the presence of a catalyst to produce a hydroxyalkanal. A method for producing a hydroxyalkanal, which comprises adding a carboxylic acid to the reaction system when an ion-exchange resin supporting a metal is used as the catalyst. 2. The method for producing a hydroxyalkanal according to claim 1, wherein the amount of the carboxylic acid added to the unsaturated aldehyde is in the range of 0.01% by weight to 10% by weight. 3. The method for producing hydroxyalkanal according to claim 1, wherein the carboxylic acid is a polyvalent carboxylic acid. 4. The method for producing a hydroxyalkanal according to claim 1, wherein the carboxylic acid is oxalic acid. 5. The method for producing a hydroxyalkanal according to claim 1, wherein the metal is lead. 6. The method for producing a hydroxyalkanal according to claim 1, 2, 3, 4 or 5, wherein the unsaturated aldehyde is acrolein.