JPH02286638A - Production of branched dimerized alcohol - Google Patents

Abstract

PURPOSE:To obtain in a short time the title compound of good quality in high yield and selectivity by heating condensation of a primary alcohol in the presence of an alkaline catalyst and cocatalyst comprising copper, a 4th period transition metallic element and group III platinum-series element. CONSTITUTION:The objective compound of formula II can be obtained by dehydration condensation of a compound of formula I (R is 1-24C alkyl. cycloalkyl, aryl or aralkyl) in the presence of (A) an alkaline catalyst (pref. KOH) and (B) a cocatalyst comprising copper, a transition metallic element (e.g. Cr, Co, Ni) and platinum-series element (e.g. Pt, Pd) at 180-220 deg.C for 1-2hr. For the catalyst B, the molar ratios are as follows: copper/transition metallic element = (1:9) (9:1) and platinum-series element/(copper + transition metallic element) = 0.001-0.1. The amounts of the catalysts A and B are such as to be 0.3-2.0wt.% and 0.005-0.2wt.% based on the compound of the formula I, respectively. The present compound of the formula II is low in both iodine value and CHO concentration.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for dehydrating and condensing primary alcohols to obtain branched trimerized alcohols.

[Prior art and problems to be solved by the invention] Conventionally, when a primary alcohol is heated and condensed in the presence of an alkaline substance or an alkaline substance and a co-catalyst, one molecule of water is removed from two molecules of raw alcohol, and 1 It is widely known that molecular branched dimerized alcohols can be obtained and is called the Guerbet reaction. Many reports have already been published regarding the reaction mechanism of this Guerbet reaction, and the mechanism is thought to be as follows.

RCHzCHzOH→RCH2CHO+ H2...
(1) 2RCH2CHO→ RCHzCll-CCHO
+ H2O... (2) PCI (2C) 12011
+KOI(-) RCHzCOOK + 2H2...
(5) In the above formula, R represents a group selected from the group consisting of alkyl, cycloalkyl, aryl, and aralkyl groups having 1 to 24 carbon atoms.

The branched dimerized alcohol represented by the above general formula (+1) is thought to be produced by the parallel reactions of the above formulas (1) to (4). The reaction rates of formulas (1) to (4) vary depending on the reaction temperature, the amount of alkali, the amount and type of co-catalyst, and the selectivity naturally varies. In addition, the reaction of formula (5) is a side reaction that is generally likely to occur at high temperatures and consumes the raw alcohol Tll, so if the reaction of formula (5) occurs, the yield of the desired branched dimerized alcohol (II) will decrease. . Therefore, cocatalysts have been investigated in order to control the reaction of formula (5) and promote the reactions of formulas (1) to (4). For example, copper chromite,
Copper zinc, copper powder, zinc oxide, zinc chromite, stabilized nickel, nickel supported on alumina silicate or activated carbon, platinum, palladium, ruthenium, rhodium, or Raney alloy with nickel, chromium, copper, etc.) and their development catalysts. It has been used as a promoter.

However, the production of high quality branched dimerized alcohol (II) with improved reaction rates of formulas (3) and (4) has not yet been achieved. By using the above cocatalyst, the reactions of formulas (1) and (2) were promoted and the conversion rate was increased, but on the contrary, aldehyde compounds,
This increased by-products of unsaturated compounds and carboxylic acids, leading to a decrease in yield and selectivity.

In particular, by-produced aldehyde compounds and unsaturated compounds cause odor, coloring, and oxidation, and have been a serious hindrance to subsequent application development.

In order to improve this drawback, the present inventors have
No. 59432 proposed a copper-nickel catalyst as a promoter. However, although the improvement effect was recognized,
The reaction rate was slow and the performance of the cocatalyst was not sufficient.

[Means to solve the problem]

The present inventors have found that the side reaction of formula (5), which is a problem in the production of the above-mentioned branched dimerized alcohol, progresses when the reaction is carried out at high temperature for a long time, and as a result, the alkaline substance that is the main catalyst decreases. , thought to cause an increase in by-products,
In order to solve this problem, we conducted extensive research to develop a cocatalyst that would increase the reaction rate. As a result, we found that a small amount of group 8 The present invention was completed by discovering that a catalyst containing a platinum group element has high activity and improves the reaction rate of the Guerbet reaction.

That is, the present invention provides the following formula: .) The alcohol represented by (a) is heated and condensed in the presence of a catalyst consisting of an alkaline substance and (b) a catalyst containing copper, a fourth period transition metal element, and a group 8 platinum group element. The present invention provides a method for producing a branched dimerized alcohol characterized by the following.

When the catalyst of the present invention containing copper, a period 4 transition metal element, and a group 8 platinum group element is used in the reaction, a copper chromite catalyst, a Raney-Ninkel catalyst, a palladium- Carbon catalyst, copper as mentioned above
Not only is it several times as powerful as a nickel catalyst, but it also provides a catalytic effect on the reaction formulas (3) and (4) above, resulting in a branched dimerized alcohol containing fewer aldehyde compounds and unsaturated compounds.

Furthermore, by increasing the reaction rate, the reaction can be carried out at a lower temperature, and by reducing the reaction rate, the by-product of carboxylic acid salt [reaction formula (5)] is suppressed, and the rate at the final stage of the reaction is reduced. Since the main catalyst, that is, the alkaline substance, is not consumed by the neutralization of the carboxylic acid produced by the side reaction, it is also possible to reduce the amount of the main catalyst, that is, the alkaline substance used.

The alkaline substances constituting the catalyst (a) used in the present invention include sodium metal, sodium alcoholade, sodium hydroxide, sodium carbonate, sodium amide, potassium metal, potassium hydroxide, potassium amide, potassium carbonate, and phosphoric acid. Examples include potassium. Among these, potassium hydroxide is preferred. The amount of catalyst (a) used may be the same as the amount commonly used in the Guerbet reaction, but a cocatalyst (bl) containing copper, a fourth period transition metal element, and a group 8 platinum group element may be used. Therefore, the proportion of alkaline substances consumed as alkali salts of carboxylic acids can be suppressed, so the amount of alkaline substances can be reduced from about half to about 1/4 in the conventional method.
The amount is enough to have a catalytic effect. The main catalyst (a) is 0.15 to 3% by weight, preferably 0.3 to 2% by weight based on the raw material alcohol.
．． It is used in a range of 0% by weight.

The cocatalyst (b) used in the present invention must contain copper, a 4th period transition metal element, and a 8th group platinum group element (hereinafter abbreviated as platinum group element). The ratio of copper, 4th period transition metal element, and platinum group element is copper/4th period transition metal element - 1/9 to 9/1, and platinum group element/(heir 4th period transition metal element)
= range of 0.001 to 0.1.

The fourth period transition metal element used to constitute the promoter (b) is at least one selected from the group consisting of chromium, cobalt, nickel, manganese, iron, and zinc, and the platinum group element is platinum. At least one selected from the group consisting of , palladium, ruthenium, and rhodium is used.

In the present invention, the promoter (b) can be selected from various forms. In the present invention, the effect of the interaction between these three components is exhibited only when the three components of copper, fourth period transition metal elements, and platinum group elements are present in the reaction system as a catalyst composition, and these three components are It has a co-catalyst function.

Therefore, the preferable forms of the three metal elements constituting the cocatalyst (b) are as follows: 1) In the reaction medium, such as an elemental metal, an oxide or hydroxide of the metal, or a mixture thereof, etc. A type of material that is dispersed by

2) A mixture of the three components copper, a fourth period transition metal element, and a platinum group element each supported on a suitable carrier, or a mixture of the three components supported uniformly on the same carrier. , in such a form that it is dispersed in the reaction medium.

3) Those in the form of metal colloids and homogeneous systems in the reaction medium, such as fatty acid carboxylates of metals or complexes stabilized with appropriate ligands.

4) A mixture of 1) and 2) in a form that is dispersed in the reaction medium and 3) in a form that is homogeneous in the reaction medium.

etc., and any form may be used as long as the interaction of the three component metals is expressed.

The cocatalyst (b) is used for stabilizing the catalyst metal,
That is, from the viewpoint of immobilization of the active surface and durability against catalyst poisoning substances, it is preferable to have the above three types of metals supported on a suitable carrier.

When copper, fourth period transition metal elements, and platinum group elements are supported on a carrier, suitable carriers include those commonly used, such as alumina, silica-alumina, diatomaceous earth, silica, activated carbon, natural and synthetic zeolites, etc. can be used. The amount of the three types of metals supported on the carrier may be arbitrary, but it is preferably in the range of 5 to 70% based on the carrier.

Various methods can be selected for supporting copper, the fourth period transition metal element, and the platinum group element on the carrier. In this case, the forms of the catalyst raw material metals include oxides of each metal; hydroxides:
Examples include metal salts such as chlorides, sulfates, acetates, and aliphatic carboxylates; metal complexes such as acetylacetone complexes and dimethylglyoxime complexes, and especially for platinum group elements, carbonyl complexes, amine complexes, and phosphine complexes. etc. can also be used.

Methods for supporting these metal raw materials on a carrier include: ■ A method in which the carrier is placed in a solution of an appropriate metal salt, sufficiently impregnated, and then dried and fired (impregnation method) ■ The carrier and an appropriate metal salt After thoroughly mixing an aqueous solution of the metal salt, add an alkaline aqueous solution such as sodium carbonate, sodium hydroxide, or aqueous ammonia to precipitate the metal salt on the carrier, or add an aqueous solution of the appropriate metal salt and sodium carbonate to the aqueous slurry of the carrier. slurry with an alkaline aqueous solution such as sodium hydroxide, or aqueous ammonia, and keep the pH constant (for example, pH=
7) A method of precipitating metal salts on a carrier by simultaneously adding them while maintaining the same temperature (co-precipitation method).
Method for ion-exchanging periodic transition metal elements and platinum group elements (ion exchange method)■ Copper, fourth period transition metal elements,
Methods include heating and melting platinum group elements and aluminum metals, cooling and solidifying them to form an alloy, and eluting the aluminum in the alloy with an alkali such as sodium hydroxide (alloy method). However, for example, in the case of the coprecipitation method (■), after the metal is deposited, rinse thoroughly with water and
After drying at around C, a cocatalyst is obtained by calcining at 300 to 700°C.

In the method for producing a branched dimerized alcohol of the present invention,
By using the cocatalyst (b) as described above, the reaction can be carried out at a lower reaction temperature than conventional methods. The reaction is preferably carried out at a temperature in the range of 180 to 220°C; if the reaction temperature is lower than 180°C, the reaction rate is slow, and if it is higher than 220°C, the reaction formula (5) described above is Side reactions such as this occur. The reaction time is preferably 1 to 2 hours.

In the present invention, the cocatalyst (b) is 0.002 to 1.0% by weight, preferably 0.005 to 1.0% by weight based on the raw material alcohol.
0.2% by weight is used.

The raw material alcohol used in the present invention has the following general formula (1
Any primary alcohol represented by 1 may be used.

R-CH2-CH2-OH... (11 (In the formula, R is a group selected from the group consisting of alkyl, cycloalkyl, aryl, and aralkyl groups having 1 to 24 carbon atoms.) The reaction of the present invention is a dehydration reaction. Generally, the reaction proceeds while removing the water produced during the reaction from the reaction system.For this purpose, it is common to carry out the dehydration reaction while refluxing the raw alcohol at a temperature above the boiling point of the raw alcohol. However, if the boiling point of the raw alcohol and the reaction temperature are different, the reaction is carried out under appropriate pressure or reduction.

Alternatively, a method may be used in which the reaction water is expelled from the reaction system while blowing inert gas such as nitrogen gas.

〔Example〕

The present invention will be explained in more detail with reference to the following examples, but the present invention is not limited to these examples.

Example 1 A three-component cocatalyst consisting of copper, a fourth period transition metal element, and a platinum group element supported on synthetic zeolite was prepared as follows.

Synthetic zeolite was placed in a No. 11 flask manufactured by Wufu Shaobin, and then copper nitrate, nickel nitrate, and palladium chloride were added to water so that the molar ratio of each metal atom was Cu:Ni:Pd=4:1:0.05. The mixture was poured into the flask, and the temperature was raised to 90°C while stirring. Then add 10% Na2C to this
O3 aqueous solution was gradually added dropwise.

After aging for 1 hour, the precipitate was filtered, washed with water, dried at 80°C for 10 hours, and then calcined at 400°C for 3 hours to obtain a cocatalyst supported on synthetic zeolite.

The amount of the obtained co-catalyst supported on the metal oxide support was 5
It was 0%.

Next, using the cocatalyst obtained as described above, a reaction was carried out to form a gel for alcohol production.

11 4-way flasks equipped with a 4-way stirrer, a thermometer, a nitrogen blowing tube, and a condenser and a separator to separate the reaction water;
505 g of decanol-1 (99% purity), 7.5 g of granular potassium hydroxide, and 0.05 g of the above cocatalyst were charged,
Nitrogen gas is passed through a flowmeter and bubbled into the system at 301/hr to raise the temperature in the system. The reaction start time is when the system temperature reaches 220°C, and the reaction is continued for 2 hours until the reaction water stops coming out.
Continue the reaction at 20°C. After a reaction time of 1 hour and 25 minutes, the reaction was stopped and cooled.

The reaction solution was filtered to remove the copper-nickel-palladium catalyst and precipitated potassium salt of carboxylic acid, and the filtrate was distilled under reduced pressure to obtain 2-octyldodecanol-1, which is a branched dimerized alcohol. .

The yield of 2-octyldodecanol-1 obtained was 430
．． The theoretical yield was 91.1% at 0 g, and the selectivity was 97.0%.
Met. Further, the iodine value of 2-octyldodecanol 1 was 1.2, and the CIO concentration was 128 ppm.

As for the quality of the fractionated trimerized alcohol, it is preferable that the iodine value (degree of unsaturation) and C110 concentration are low. (The same applies to the following examples.) Comparative Example-1 Instead of a copper-nickel-palladium catalyst as a co-catalyst, a copper-nickel catalyst (80% by weight of copper and 20% by weight of nickel) was used as a promoter.
In terms of weight%, the total proportion of copper and nickel in the total catalyst is 40% by weight) 0.05g was used, and the rest were Example-1
The reaction was carried out on the gel in the same manner as above. The reaction time was 3 hours.

The yield of 2-octyldodecanol-1 obtained was 424
．． The theoretical yield was 89.9% at 0 g, and the selectivity was 95.0%.
Met. Further, the iodine value of 2-octyldodecanol 1 was 1.5, and the CHO concentration was 148 ppm.

Examples-2 to 7 and Comparative Example-2 N++ Co+ Cr as the fourth period transition metal element
Using MnFe, Zn and Ru as the platinum group element, various co-catalysts consisting of copper, fourth period transition metal elements, and platinum group elements as shown in Table 1 were mixed with Cu/fourth period transition metal. It was prepared in the same manner as in Example-1 so that the element/Ru composition ratio = 4/110.02, and these various co-catalysts and a copper-nickel catalyst (Cu /Ni composition ratio -4/1), octano-1 was used as the raw alcohol, and other conditions were the same as in Example 1, and the gel was reacted. Hexyldecanol-1 was obtained.

Catalyst composition, reaction time, theoretical yield and selectivity, iodine value of 2-hexyldecanol-1 and C) in each reaction
The to concentrations are shown in Table-1.

Table 1 In Examples 2 to 7, the co-catalysts exhibited more than twice the activity as compared to Comparative Example 2, and the selectivity was also improved. Moreover, the quality of the obtained 2-hexyldecanol=1 is also good.

Examples 8 to 11 and Comparative Example 3 ■8 Using Zn as the fourth period transition metal element and using Ru, pt, Pd + Rh as the platinum group elements, copper and Various promoters consisting of a 4th period transition metal element and a platinum group element were prepared in the same manner as in Example 1 so that the composition ratio of Cu/4th period transition metal element/Ru was -4/110.02. various promoters, and the same copper-nickel catalyst (Cu
/Ni composition ratio -4/1), dodecanol-1 was used as the raw alcohol, and the other conditions were the same as in Example 1. Tetradecanol was obtained.

Catalyst composition, reaction time, theoretical yield and selectivity, iodine value and Cl of 2-decyltetradecanol in each reaction
The l0 concentration is shown in Table-2.

In Examples 8 to 11 in the table, the cocatalyst exhibits more than twice the activity as compared to Comparative Example 3, and the selectivity is also improved. Moreover, the quality of the obtained 2-decyltetradecanol is also good.

Examples ~12~17 A Cu-NiRu catalyst prepared in the same manner as in Example-1 (metal composition ratio Cu
/Ni/Ru=4/ ] 10.02), and the reaction to give Tekel was carried out in the same manner as in Example 1, except that the amounts of each catalyst were varied as shown in Table 3. Xyldecanol-1 was obtained.

Table 3 shows the catalyst composition, reaction time, theoretical yield and selectivity, iodine value and Cll0 concentration of 2-hexyldecanol-1 in Examples-12 to I7 and Comparative Example-1.

In the reaction by Akira, the amount of main catalyst used was about 1/4 and the amount of co-catalyst was about 1/2 compared to Comparative Example 1, which is a conventional method.
/2.5, respectively.

〔Effect of the invention〕

According to the method for producing a branched trimerized alcohol of the present invention, the reaction time can be shortened compared to conventional methods, and the yield and selectivity of alcohol can be improved.

In addition, the produced branched trimerized alcohol has an iodine value and C
The I(O concentration is low and the quality is better than alcohol obtained by conventional methods.

Furthermore, according to the production method of the present invention, the amount of the alkaline substance used as the main catalyst can be reduced compared to conventional methods.

Claims (1)

[Claims] 1 General formula (I) R-CH_2-CH_2-OH...(I) (in the formula R
is a group selected from the group consisting of alkyl, cycloalkyl, aryl and aralkyl groups having 1 to 24 carbon atoms. ) The alcohol represented by (a) is heated and condensed in the presence of a catalyst made of an alkaline substance and (b) a catalyst containing copper, a fourth period transition metal element, and a group 8 platinum group element. A method for producing a branched dimerized alcohol, characterized by: 2 (b) The molar ratio of the catalyst containing copper, a fourth period transition metal element, and a group 8 platinum group element is copper/fourth period transition metal element = 1/9 to 9/1, and Group 8 platinum group element/(copper + 4th period transition metal element) = 0.001 to 0.1
The method for producing a branched dimerized alcohol according to claim 1. 3. The 4th period transition metal element is at least one selected from the group consisting of nickel, chromium, cobalt, manganese, iron, and zinc, and the 8th group platinum group element is the group consisting of platinum, palladium, ruthenium, and rhodium. The method for producing a branched dimerized alcohol according to claim 1, wherein at least one kind is selected from the following.