JPH061736A - Production of higher secondary alcohol - Google Patents

Abstract

PURPOSE:To provide the method enabling to produce higher secondary alcohol in a high yield by the direct hydration of a higher alpha-ilefin. CONSTITUTION:The method for producing higher secondary alpha-olefin by the direct hydration of a high alpha-oilefin in charcterized by suspending the higher alpha-olefin in an equious solution containing >=50wt.% of a heterpolyacid as a catalyst and subjecting the higher alpha-olefin to a direct hydration reaction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a higher secondary alcohol useful as a raw material for detergents, and more particularly to a method for producing a higher secondary alcohol by direct hydration reaction of a higher α-olefin.

[0002]

2. Description of the Related Art There are many reports on a two-stage hydration method in which an α-olefin is reacted with sulfuric acid to form a sulfuric acid ester, and the sulfuric acid ester is hydrolyzed to an alcohol. However, this two-stage hydration method has the drawback that the device is corroded by sulfuric acid and the product alcohol is colored.

In addition, 2 by direct hydration of α-olefins
Many conventional methods for producing a primary alcohol have been known.

For example, Japanese Patent Publication No. 49-36203 discloses a method for directly hydrating propylene and butene using a heteropolyacid as a catalyst to synthesize isopropanol, sec-butanol and tert-butanol. In addition, Japanese Patent Publication No. 58-39134 discloses that
N using an aqueous solution containing 10% by weight or more of heteropolyacid
-A method for selectively hydrating isobutylene from an olefin mixture containing butene and isobutylene to produce tert-butanol is disclosed.

[0005]

The alcohol production examples of the above-mentioned prior art documents are limited to the production examples of lower secondary alcohols by the direct hydration of lower α-olefins.
There is no mention of obtaining higher secondary alcohols from olefins. The reason is that, when a higher secondary alcohol is produced by direct hydration of a higher α-olefin, the thermodynamic chemical equilibrium constant K of the direct hydration reaction is extremely small, and the hydration reaction hardly progresses. It is presumed that the yield of the product secondary alcohol is extremely low.

Therefore, it is an object of the present invention to provide a method capable of obtaining a higher secondary alcohol in a high yield by directly hydrating a higher α-olefin.

[0007]

As a result of intensive studies by the present inventors for achieving the above object, the higher α-olefin is directly hydrated in the presence of an aqueous solution containing 50% by weight or more of a heteropolyacid as a catalyst. As a result, they found that a higher secondary alcohol can be obtained efficiently, and completed the present invention.

That is, according to the present invention, when the higher α-olefin is directly hydrated to produce a higher secondary alcohol, an aqueous solution containing 50 wt% or more of a heteropolyacid as a catalyst is suspended in the higher α-olefin. The gist is a method for producing a higher secondary alcohol, which is characterized by carrying out a direct hydration reaction.

According to a preferred embodiment of the present invention, 5
A metal salt of an acid can be added as a cocatalyst to an aqueous solution containing 0% by weight or more of a heteropolyacid.

The present invention will be described in detail below. In the present invention, the higher α-olefin used as a raw material has 8 carbon atoms.
The above are preferable, for example, 1-octene (C ₈ ), 1-decene (C ₁₀ ), 1-dodecene (C ₁₂ ), 1-tetradecene (C ₁₄ ), 1-hexadecene (C ₁₆ ), 1- Octadecene (C ₁₈ ) and the like can be mentioned.

In the present invention, the heteropolyacid that can be used as a catalyst contains tungsten, molybdenum or vanadium as a condensation coordination element. For example, silicotungstic acid (SiO ₂ .12WO)
₃ ), phosphotungstic acid (P ₂ O ₅ .24WO ₃ ),
Examples thereof include phosphomolybdic acid (P ₂ O ₅ .24MoO ₃ ).

The concentration of the aqueous solution of heteropolyacid is 50% by weight.
Limited to the above. The reason is that the heteropoly acid concentration is 5
This is because when the content is less than 0% by weight, the hydration reaction does not proceed and secondary alcohol is hardly obtained. A part of the heteropolyacid may be crystallized in the heteropolyacid aqueous solution.

In the present invention, examples of the metal salt of an acid used as a cocatalyst include metal inorganic salts such as metal nitrates, metal phosphates and metal sulfates, as well as metal carboxylates and metal sulfonates. Mention may be made of organic acid salts. Among these, metal nitrates are particularly preferable, for example, chromium nitrate (Cr (NO ₃ ) ₃ ) and copper nitrate (Cu (N
O _{3) 2),} and the like cobalt nitrate (Co (NO _{3) 2)} is.

The amount of the metal salt of the acid as the cocatalyst added is not particularly limited, but is 0.01% by weight based on the catalyst.
It is preferably not less than 20% by weight. If the addition amount of the acid metal salt is less than 0.01% by weight, the effect of adding the cocatalyst may not be clear, and even if it is added in excess of 20% by weight, the effect of adding the cocatalyst is not This is economically unfavorable because it will gradually reach a ceiling.

In the direct hydration reaction of the present invention, the ratio of the raw material α-olefin to water is preferably 1 ≦ W / O ≦ 100, where (water / α-olefin) = W / O. When W / O is less than 1, the hydration reaction may not proceed, and when W / O exceeds 100, the reaction vessel needs to be large, which is not economically preferable.

The stirring speed for suspending the aqueous solution containing 50% by weight or more of the heteropolyacid and the higher α-olefin is not particularly limited, but the higher the stirring speed, the smaller the dispersed particle size of the suspension. And is advantageous for the reaction. However, the stirring speed largely depends on the shape and size of the container, the shape of the stirrer, and the like, and it is necessary to appropriately select the stirring speed in accordance with these factors.

The lower the reaction temperature, the more advantageous it is from the viewpoint of reaction equilibrium. However, in consideration of the reaction rate, it is usually room temperature (25 ° C.) to 200 ° C., preferably 100 to 175 ° C.

The reaction pressure may be any pressure as long as the reaction system is kept in the liquid phase without vaporizing the reaction liquid. In order to keep the reaction system in the liquid phase, pressurization with an inert gas may be appropriately performed.

The reaction time is not particularly limited, but it is practically 1
It is preferably about 6 hours.

The reaction system is not particularly limited, and the reaction can be performed in a batch system, a semi-batch system, a continuous system or the like.

[0021]

The present invention will be further described with reference to the following examples.

Examples 1 to 4 and Comparative Examples 1 to 2 Higher α-values were obtained by varying the heteropolyacid (HPA) concentration.
Direct hydration of olefins was performed.

(Example 1) 14.5 g of 1-decene, a heteropoly acid (HP) in a 250 cc titanium autoclave
72 g of silicotungstic acid was charged as A), the HPA concentration in the aqueous solution was 50%, and the water / olefin molar ratio (W
/ O) was set to 20, and the mixture was stirred at a temperature of 150 ° C. for 2 hours at a stirring rate of 530 rpm. After the completion of the reaction, the decene conversion rate (%), the secondary alcohol selectivity (%), and the content rate (%) of various secondary alcohols in the total secondary alcohols were measured.

(Examples 2-4 and Comparative Examples 1-2) HP
A concentration of 60% (Example 2), 70% (Example 3), 8
A direct hydration reaction was carried out in the same manner as in Example 1 except that the amounts were 0% (Example 4), 40% (Comparative Example 1) and 10% (Comparative Example 2). The results are shown in Table 1.

[0025]

[Table 1] HPA: represents heteropoly acid. It represents the molar ratio of W / O: (water / olefin). Decene conversion rate: Shown by the value calculated by the following calculation formula. Decene conversion rate (%) = (area value other than decene) / (area value of peak derived from decene + area value other than decene) × 100 Secondary selectivity (%): Means secondary alcohol selectivity, It is shown by the value calculated by the following formula. Secondary alcohol selectivity (%) = (total secondary alcohol isomer area value) / (area value other than decene) × 100 Content rate (%) (Secondary content rate (%)): Obtained secondary The ratio of each secondary alcohol isomer in alcohol determined by the gas chromatography method is shown. (The terms in the above table have the same meanings in Tables 2 to 7 below.)

From Table 1, the following has become clear. When the HPA concentration is less than 50% as in Comparative Examples 1 and 2, 2
While no secondary alcohol is obtained (secondary alcohol selectivity 0%), when the HPA concentration is 50%, the secondary alcohol selectivity rapidly rises to 24.3%. Further HP
When the A concentration is 60%, the secondary alcohol selectivity is 8
It rapidly rises to 3.4%, and a high secondary alcohol selectivity is obtained at HPA concentrations of 70% and 80%.

Examples 2 and 5-6 Direct hydration reactions of higher α-olefins were carried out by varying the reaction temperature. The reaction temperature was 100 ° C. (Example 5), 1
A direct hydration reaction was carried out in the same manner as in Example 2 (reaction temperature 150 ° C.) except that the temperature was 75 ° C. (Example 6). The results are shown in Table 2.

[0028]

[Table 2] The following are clear from Table 2. Reaction temperature 100
It shows a high decene conversion rate and a secondary alcohol selectivity at a temperature of from ℃ to 175 ℃. The decene conversion rate and the total secondary alcohol selectivity were highest at a reaction temperature of 150 ° C., and all the following Examples and Comparative Examples were reacted at 150 ° C.

Examples 3 and 7-8 Direct hydration of higher α-olefins was carried out by varying the water / olefin molar ratio (W / O). The direct hydration reaction was carried out in the same manner as in Example 3 (W / O = 20) except that the water / olefin molar ratio (W / O) was changed to 1 (Example 7) and 100 (Example 8). . The results are shown in Table 3.

[0030]

[Table 3] The following are clear from Table 3. W / O is 1 to 1
When 00, high decene conversion and secondary alcohol selectivity are obtained.

Examples 3 and 9 to 11 Direct hydration reaction of higher α-olefin was carried out by changing reaction time variously. A direct hydration reaction was performed in the same manner as in Example 3 (2 hours) except that the reaction time was 0 hour (Example 9), 4 hours (Example 10), and 6 hours (Example 11). The results are shown in Table 4. In addition, Examples 3 and 9 to 11
In all the examples and comparative examples of the present invention, including, the reaction time was set such that after the reaction raw materials were charged into the autoclave, the temperature was raised to a predetermined temperature (the present examples 3 and 9-
In 11, we decided to start counting from the time when it reached 150 ° C. Therefore, the reaction time of 0 hours in Example 9 means that the reaction mixture was sampled and analyzed when the temperature reached a predetermined temperature of 150 ° C., and the reaction times of Examples 3, 10, 11 were 2, 4 and 6 hours. Means that the reaction mixture was sampled and analyzed after the reaction was continued for each time from the time when the predetermined temperature was reached.

[0032]

[Table 4] From Table 4, it was revealed that the decene conversion rate increases as the reaction time increases, but the secondary alcohol selectivity shows a high value in the case of 2 hours to 6 hours.

Examples 12 to 14 Direct hydration of higher α-olefins was carried out by changing the type of heteropolyacid (HPA).

Example 12 14.5 g of 1-decene and heteropolyacid (HPA) were added to a 50 cc glass autoclave.
Was charged with 120 g of silicotungstic acid, the HPA concentration in the aqueous solution was 70%, and the water / olefin molar ratio (W /
After setting O) to 20, the mixture was stirred at a temperature of 150 ° C. for 2 hours at a stirring speed of 1000 rpm. The results are shown in Table 5.

(Examples 13 to 14) Heteropoly acid (HP
Example 1 except that the types of A) were phosphotungstic acid (Example 13) and phosphomolybdic acid (Example 14)
The hydration reaction was carried out in the same manner as in 2. The results are shown in Table 5.

[0036]

[Table 5] Secondary alcohol yield (%): Shows the yield of total secondary alcohol, and was calculated by decene conversion rate (%) × secondary alcohol selectivity (%) (the same meanings are given in Tables 6 and 7 below). ).

The following is clear from Table 5. Comparing the three kinds of heteropolyacids in Table 5, phosphotungstic acid (P ₂ O ₅ .24WO ₃ ) has high secondary alcohol selectivity and yield, but other heteropolyacids have almost the same catalytic activity. Show.

Examples 15 to 18 Direct hydration reaction of higher α-olefins was carried out by changing the kind and addition amount of cocatalyst and the reaction time.

Example 15 A 50 cc glass autoclave was charged with 2.9 g of 1-decene, 24 g of phosphotungstic acid as a heteropolyacid (HPA) and 0.2 g of cobalt nitrate as a cocatalyst, and the HPA concentration in the aqueous solution was 7 g.
After setting so that the water / olefin molar ratio (W / O) was 0%, the mixture was stirred at a temperature of 150 ° C. for 1 hour at a stirring speed of 1000 rpm. The results are shown in Table 6.

(Examples 16 to 18) The kind and addition amount of the cocatalyst and the reaction time were 0.3 g of copper nitrate for 1 hour (Example 16), 0.3 g of chromium nitrate for 1 hour (Example 17),
A direct hydration reaction was carried out in the same manner as in Example 15 except that 0.3 g of chromium nitrate was used for 2 hours (Example 18). The results are shown in Table 6.

[0041]

[Table 6] The following is clear from Table 6. From the comparison with Examples 12 to 14 in Table 5 in which the co-catalyst is not added, the decene conversion rate is improved by adding the co-catalyst even if the reaction time is short.

Comparing Examples 13 and 18 with the same reaction time, the addition of cocatalyst significantly improves the decene conversion and the yield of secondary alcohol.

Further, from the comparison of Examples 17 and 18 in which the reaction conditions other than the reaction time are the same, when the reaction time becomes longer, the decene conversion rate, the secondary alcohol selectivity and the secondary alcohol yield are improved.

Comparative Examples 3 to 5 The direct hydration reaction of the higher α-olefin was carried out without using the heteropolyacid and adding only various metal nitrates which are the metal salts of the acid used as the promoter in the present invention. .

Comparative Example 3 A 50 cc glass autoclave was charged with 2.9 g of 1-decene and 0.3 g of cobalt nitrate as a metal nitrate, and the molar ratio of water / olefin (W /
After setting O) to be 23.5, the mixture was stirred at a temperature of 150 ° C. for 1 hour at a stirring speed of 1000 rpm.
The results are shown in Table 7.

(Comparative Examples 4 to 5) A direct hydration reaction was carried out in the same manner as in Comparative Example 3 except that the added metal nitrates were copper nitrate (Comparative Example 4) and chromium nitrate (Comparative Example 5). The results are shown in Table 7.

[0047]

[Table 7] The following are clear from Table 7. Without using the heteropolyacid which is the catalyst of the present invention, the hydration reaction of decene hardly proceeds and no secondary alcohol is obtained.

In addition, the metal salt of the acid which is the co-catalyst of the present invention alone does not cause the direct hydration reaction of the higher α-olefin.

[0049]

According to the present invention, a hydration reaction proceeds by suspending an aqueous solution containing 50% by weight or more of a heteropolyacid and a higher α-olefin to obtain a higher secondary alcohol in a high yield. To be

Further, by adding a metal salt of an acid as a co-catalyst to an aqueous solution containing a heteropolyacid, a higher α
-It is possible to further improve the reaction rate of the direct hydration reaction of the olefin and the yield of the higher secondary alcohol which is the target.

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[Procedure amendment]

[Submission date] June 30, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0023

[Correction method] Change

[Correction content]

(Example 1) 14.5 g of 1-decene, a heteropoly acid (HP) in a 250 cc titanium autoclave
72 g of a silicotungstic acid aqueous solution was charged as A),
After setting the HPA concentration in the aqueous solution to 50% and the water / olefin molar ratio (W / O) to 20, 150 ° C
Stirring was carried out at a stirring speed of 530 rpm for 2 hours at the temperature of. After the completion of the reaction, the decene conversion rate (%), the secondary alcohol selectivity (%), and the content rate (%) of various secondary alcohols in the total secondary alcohols were measured.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0034

[Correction method] Change

[Correction content]

Example 12 14.5 g of 1-decene and heteropolyacid (HPA) were added to a 50 cc glass autoclave.
As a solution, 120 g of silicotungstic acid aqueous solution was charged, and the HPA concentration in the aqueous solution was set to 70% and the water / olefin molar ratio (W / O) was set to 20, then, the temperature was 150 ° C. for 2 hours, and the stirring speed was 1000 rpm. The mixture was stirred at. The results are shown in Table 5.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0039

[Correction method] Change

[Correction content]

Example 15 A 50 cc glass autoclave was charged with 2.9 g of 1-decene, 24 g of an aqueous solution of phosphotungstic acid as a heteropolyacid (HPA) and 0.2 g of cobalt nitrate as a cocatalyst, and the HPA concentration in the aqueous solution was 70%. , Water / olefin molar ratio (W / O) is 20
After that, the mixture was stirred at a temperature of 150 ° C. for 1 hour at a stirring speed of 1000 rpm. The results are shown in Table 6.

Claims (3)

[Claims] 1. When directly hydrating a higher α-olefin to produce a higher secondary alcohol, the aqueous solution containing 50% by weight or more of a heteropolyacid as a catalyst and the higher α-olefin are suspended to directly hydrate. A method for producing a higher secondary alcohol, which comprises carrying out a reaction. 2. The method according to claim 1, wherein a metal salt of an acid is added as a cocatalyst to an aqueous solution containing 50% by weight or more of a heteropolyacid. 3. The method according to claim 2, wherein the metal salt of the acid is a metal nitrate.