JPH08169855A - Production of higher alcohol - Google Patents

Abstract

PURPOSE: To obtain a higher alcohol with suppressed byproduct formation without shortening catalyst life by hydrogenating an oil-and-fat or fatty acid ester in the presence of a hydrogenation catalyst and a specified amount of a basic substance. CONSTITUTION: An oil-and-fat (e.g. coconut oil) or fatty acid ester (e.g. coconut oil fatty acid methyl ester) is hydrogenated in the presence of a hydrogenation catalyst (e.g. a copper-chromium oxide) and 0.1-1000ppm, based on the oil-and-fat or fatty acid ester, of a basic substance (e.g. a methanol solution of sodium hydroxide) to obtain the objective higher alcohol. This method needs no pretreatment such as distillation, and the hydrogenation can preferably be continued for a long time without shortening catalyst life, with suppressed formation of byproducts such as dialkyl ethers, alkyl methyl ethers or hydrocarbons.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing higher alcohols, and more particularly to a method for industrially producing higher alcohols by hydrogenating fats and oils or fatty acid esters.

[0002]

2. Description of the Related Art Conventionally, the problems to be solved by the invention
As a method for producing higher alcohols, for example, a method is known in which fats or oils or fatty acid esters are hydrogenated at high temperature and high pressure in the presence of a hydrogenation catalyst. In this production method, a part of the higher alcohol obtained by poisoning the catalyst with a trace amount of sulfur compounds, halides, free fatty acids and the like derived from the raw material fats and oils in the hydrogenation reaction is dehydrated, and dialkyl ether and alkylmethyl are obtained. There is a problem that a large amount of ether and hydrocarbon are produced as by-products, the life of the catalyst is shortened, and the catalyst cannot be recovered and used many times. In order to avoid this, a method of removing a sulfur compound or the like derived from the raw material oil and fat from the raw material by a preliminary operation such as distillation, or a trap component of the sulfur component or the like in the raw material (Japanese Patent Laid-Open No. 5-978) is known. However, there was a problem that an increase in product cost was unavoidable.

The object of the present invention is to suppress the by-production of dialkyl ether, alkyl methyl ether, hydrocarbon and the like in the hydrogenation reaction of the oil or fat or fatty acid ester, and to prevent the catalyst life from being shortened. An object of the present invention is to provide a simple production method capable of suitably continuing the hydrogenation reaction for a long period of time.

[0004]

Means for Solving the Problems As a result of intensive studies by the present inventors in order to solve the above problems, surprisingly, hydrolysis of an ester is unexpectedly caused by a simple method of allowing a specific amount of a basic substance to coexist. The present invention has been completed by finding that the above object can be achieved without any problems.

That is, the gist of the present invention is: (1) In a method for producing a corresponding higher alcohol by hydrogenating a fat or oil or a fatty acid ester in the presence of a hydrogenation catalyst, a basic substance is added to the fat or oil or the fatty acid ester. 0.1-1000
a method for producing a higher alcohol characterized by adding ppm, (2) the oil and fat is coconut oil, palm oil, palm kernel oil,
Soybean oil, rapeseed oil, beef tallow, lard, fish oil, or hydrogenated oils thereof, (3) The method according to (1) above, wherein the fatty acid ester is coconut oil, palm oil, palm kernel oil, Soybean oil, rapeseed oil, beef tallow, lard, or fish oil transesterified with an alcohol having 1 to 18 carbon atoms, or palm oil, palm oil, palm kernel oil, soybean oil, rapeseed oil, beef tallow, lard, or A carboxylic acid obtained from fish oil, which is esterified with an alcohol having 1 to 18 carbon atoms, (4).
The basic substance is an alkali metal or alkaline earth metal hydroxide, bicarbonate, or carbonate, an alcoholate having a hydrocarbon group having 1 to 18 carbon atoms, and an amine having a hydrocarbon group having 1 to 18 carbon atoms. Or (5) the hydrogenation catalyst is a copper-based catalyst, and (1) to (4) above. The manufacturing method according to any one of the above. The present invention will be described below.

The oils and fats used in the present invention include
Examples thereof include animal and vegetable oils and fats such as palm oil, palm oil, palm kernel oil, soybean oil, rapeseed oil, beef tallow, lard, and fish oil, and hydrogenated oils thereof. Here, the fish oil is not particularly limited, and examples thereof include orange luffy oil, sardine oil, mackerel oil and the like. The hardened oil is obtained by treating the above fat and oil by a known method.

The fatty acid ester used in the present invention is obtained by transesterifying the above-mentioned fats and oils with alcohol by a known method, or a carboxylic acid obtained from the above-mentioned fats and oils by a known method such as hydrolysis. Examples thereof include those obtained by esterification with alcohol by a known method.

As the alcohol used for transesterification or esterification, those having 18 or less carbon atoms are used from the viewpoint of the rate of esterification and the production efficiency of higher alcohols. That is, those having 1 to 18 carbon atoms are preferable, those having 1 to 4 carbon atoms are more preferable, and those having 1 carbon atom are particularly preferably used. Specific examples include methanol, ethanol, propanol, butanol, hexanol, octanol, decanol, dodecanol, octadecanol and the like.

Preferred specific examples of the fatty acid ester thus obtained are methyl ester, ethyl ester, propyl ester and butyl ester of coconut oil fatty acid; methyl ester, ethyl ester, propyl ester and butyl of palm oil fatty acid. Ester; Palm kernel oil fatty acid methyl ester, ethyl ester, propyl ester, butyl ester; Soybean oil fatty acid methyl ester, ethyl ester, propyl ester, butyl ester; Rapeseed oil fatty acid methyl ester, ethyl ester, propyl ester, butyl ester ; Beef tallow fatty acid methyl ester, ethyl ester, propyl ester,
Butyl ester; methyl ester, ethyl ester, propyl ester, butyl ester of tallow fatty acid; orange luffy oil fatty acid methyl ester, ethyl ester, propyl ester, butyl ester; sardine oil fatty acid methyl ester, ethyl ester, propyl ester, Butyl ester; methyl ester of mackerel oil fatty acid,
Examples thereof include ethyl ester, propyl ester and butyl ester. These fatty acid esters may be a mixture of several kinds of fatty acid esters as described above, or may be a single component.

When the fatty acid ester is used alone, the following compounds are specifically mentioned. That is, caprylic acid methyl ester, capric acid methyl ester, lauric acid methyl ester, myristic acid methyl ester, palmitic acid methyl ester, stearic acid methyl ester, caprylic acid ethyl ester, capric acid ethyl ester, lauric acid ethyl ester, myristic acid ethyl ester Ester, palmitic acid ethyl ester,
Stearic acid ethyl ester, caprylic acid propyl ester, capric acid propyl ester, lauric acid propyl ester, myristic acid propyl ester, palmitic acid propyl ester, stearic acid propyl ester, caprylic acid butyl ester, capric acid butyl ester, lauric acid butyl ester, Examples thereof include myristic acid butyl ester, palmitic acid butyl ester, stearic acid butyl ester and the like.

The above-mentioned fats and oils or fatty acid esters are hydrogenated using a hydrogenation catalyst to be converted into corresponding higher alcohols. The hydrogenation catalyst used here is not particularly limited, and generally known ones are used, but preferably a copper-based catalyst such as copper, copper-chromite, copper-zinc, or copper-iron-aluminum is used. The hydrogenation catalyst which makes it a main component is mentioned. The form is not particularly limited, and may be in the form of powder or tablet.

In the present invention, a desired effect can be obtained by allowing a basic substance to coexist when hydrogenating an oil or fat or a fatty acid ester. Here, as the basic substance, for example, a hydroxide of an alkali metal or an alkaline earth metal,
Examples thereof include carbonates or bicarbonates, alcoholates having a hydrocarbon group having 1 to 18 carbon atoms, amines having a hydrocarbon group having 1 to 18 carbon atoms, and ammonia.

Examples of the hydroxide of alkali metal or alkaline earth metal include lithium hydroxide, potassium hydroxide, sodium hydroxide, calcium hydroxide, magnesium hydroxide, barium hydroxide and the like.

Examples of the alkali metal or alkaline earth metal carbonate include lithium carbonate, potassium carbonate, sodium carbonate, calcium carbonate, magnesium carbonate, barium carbonate and the like, and bicarbonates include potassium bicarbonate and bicarbonate. Sodium, calcium bicarbonate, magnesium bicarbonate and the like can be mentioned.

In the alcoholate having a hydrocarbon group having 1 to 18 carbon atoms, preferable hydrocarbon groups include methyl, ethyl, propyl, hexyl, decyl and dodecyl. As the metal element of the alcoholate, an alkali metal or an alkaline earth metal is used, and sodium, potassium, calcium and magnesium are preferable. Carbon number 1
Specific examples of the alcoholate having a hydrocarbon group of -18 include sodium methylate, sodium ethylate, sodium dodecylate, potassium methylate and calcium methylate.

In the amine having a hydrocarbon group having 1 to 18 carbon atoms, preferred hydrocarbon groups are hexyl, decyl,
Dodecyl is an example. Specific examples of the amine having a hydrocarbon group having 1 to 18 carbon atoms include hexylamine, dodecylamine, monomethylhexylamine, monomethyldodecylamine and dimethyldodecylamine.

Among the above compounds, alkali metal hydroxides, carbonates and bicarbonates are preferable, and sodium hydroxide or potassium hydroxide is particularly preferable.

The amount of the basic substance used is 0.1 to 1000 ppm, preferably 0.5, relative to the fat or oil or the fatty acid ester.
˜500 ppm, more preferably 1 to 200 ppm. If the amount used is less than this range, the effect tends not to be sufficiently exhibited, and if it exceeds this range, the production of by-products is suppressed but the activity of the catalyst tends to decrease, resulting in a decrease in productivity.

The method of adding the basic substance to the raw material or the like is not particularly limited, and it may be added directly to the raw material or the like, and is added in a liquid form in consideration of operability and influence on the hydrogenation reaction. May be. The medium used when added in liquid form is usually the same alcohol as the alcohol part of the fatty acid ester, that is, methanol for the methyl ester,
Examples thereof include ethanol for ethyl ester, propanol for propyl ester, water, oil and fat or fatty acid ester as a raw material, and higher alcohol which is the same as the higher alcohol used as a product. The basic substance may be added after being dissolved or suspended in the medium. In any case, it is more preferable to supply them to the reactor after thoroughly mixing them with a stirrer or the like. Although the concentration of the basic substance in the medium can be arbitrarily selected, for example, in the case of a sodium hydroxide solution in methanol, a concentration of 5 to 10% by weight is suitable.

Hydrogenation of fats and oils or fatty acid esters can be carried out in the presence of a hydrogenation catalyst by either liquid phase suspension bed or fixed bed reaction system. In the case of liquid phase suspension bed reaction, the reaction temperature is 130 to 350 ° C., preferably 180 to
300 ° C., hydrogen pressure 10-350 kg / cm ² , preferably 100-250 kg / cm ² , reaction time 0.5-
It takes 5 hours. The amount of the catalyst used is in the range of 0.1 to 60% by weight, preferably 0.5 to 10.0% by weight, based on the starting oil or fat or fatty acid ester.

When the fixed bed reaction system is adopted, a purposely shaped catalyst is used. Reaction temperature is 13
0-300 ° C., preferably 160-270 ° C., reaction pressure 0.1-300 kg / cm ² , preferably 20-25
It is 0 kg / cm ² . Here, the liquid hourly space velocity (LHSV) is arbitrarily determined according to the reaction conditions, but in view of productivity or reactivity, LHSV is 0.5 to 5 (m ³ / m ³ /
The range of m ³ ) is preferred.

The reactor used in the present invention is not particularly limited, and a commonly known reactor can be used. For example, in the case of the liquid phase suspension bed reaction system, a gas-liquid solid suspension bed and the like can be mentioned. In the case of the fixed bed reaction system, a trickle reaction bed (gas-liquid parallel flow fixed bed) and the like can be mentioned.

In order to obtain the corresponding higher alcohol from the reaction product obtained as described above, further purification such as filtration and distillation of the catalyst may be carried out. However, in the present invention, since there are few by-products, only filtration of the catalyst may be performed.

[0024]

The present invention will be described below with reference to examples and comparative examples, but the present invention is not limited to these examples. Example 1 To 75 g of coconut oil fatty acid methyl ester, 3.75 g of a commercially available copper-chromium oxide catalyst (manufactured by JGC Corporation) and 10% KO
Hp methanol solution as KOH 30p for ester
pm added, hydrogen pressure 25 in 500 ml autoclave
0 kg / cm ² , reaction temperature 275 ° C., hydrogen 5 L / mi
The reaction was carried out for 7 hours. In addition, in this example, the reaction was performed in a liquid phase suspension bed system.

After completion of the reaction, the reactor was cooled, the autoclave was opened, the reaction solution was taken out, the catalyst was recovered by pressure filtration, and the recovered catalyst was charged into the autoclave again to obtain 150 g of coconut oil fatty acid methyl ester and 10%. K
An OH-methanol solution was added to the ester in an amount of 30 ppm as KOH in the same amount as in the first reaction, and the reaction was performed under the same reaction conditions as in the first reaction. This operation was performed 4 times in total. The reaction product after filtering the catalyst was subjected to oil and fat analysis and gas chromatographic analysis. The results obtained are shown in Table 1. Also,
The reaction product was distilled to obtain the corresponding higher alcohol, coconut alcohol. The coconut oil fatty acid methyl ester was obtained by transesterifying coconut oil with methanol, and the same thing was used in the following examples and the like.

[0026]

[Table 1]

As an oil and fat analysis, the saponification value of the obtained product was measured according to the method of JIS K0070. The saponification number indicates the degree of hydrogenation reaction, and when the reaction is carried out using the same raw material, a higher saponification number of the product means that there are more unreacted substances. The saponification value was measured in the same manner in the following examples.

Alcohols produced by gas chromatographic analysis and by-products in the products (hydrocarbons, dialkyl ethers, alkyl methyl ethers)
Was measured. In the table,% is the peak area of the analysis result (total peak area is 100%). The measurement conditions are shown below. SE-30 (Shimadzu) as a filler
30% by weight, chromsorb WAW as carrier
-DMCS (manufactured by Shimadzu Corporation) and FID detector (manufactured by Shimadzu Corporation) were used. The gas chromatographic analysis was similarly measured in the following examples.

Examples 2 and 3 Using 10% KOH methanol solution as KOH, 5 ppm (Example 2) and 200 ppm (Example 3) based on the ester.
The same operation as in Example 1 was performed except that the addition was made. Table 1 shows the analysis results of the product.

Comparative Example 1 The same operation as in Example 1 was carried out except that the basic substance was not added. Table 2 shows the analysis results of the product.

[0031]

[Table 2]

Comparative Examples 2 and 3 The same operation as in Example 1 was carried out except that 10% KOH methanol solution was used as KOH and 0.05 ppm (Comparative Example 2) and 2000 ppm (Comparative Example 3) were added to the ester.
Table 2 shows the analysis results of the product.

Examples 4-7 Instead of 10% KOH in methanol, 10% NaO
H methanol solution (Example 4), 48% KOH aqueous solution (Example 5), 5% KOH coconut oil fatty acid methyl ester suspension (Example 6) and 5% KOH coconut alcohol suspension (Example 7) were added. The same operation as in Example 1 was performed except that 30 ppm was added. Table 1 shows the analysis results of the product. Note that coconut alcohol is an alcohol obtained by the reduction reaction of coconut oil fatty acid methyl ester.

Examples 8-11 Instead of palm oil fatty acid methyl ester, palm oil (Example 8), palm oil fatty acid methyl ester (Example 9),
The same operation as in Example 1 was performed except that palm kernel oil fatty acid methyl ester (Example 10) and beef tallow fatty acid methyl ester (Example 11) were used. Table 3 shows the analysis results of the products. The coconut oil used in Example 1 was used. The palm oil fatty acid methyl ester, the palm kernel oil fatty acid methyl ester, and the beef tallow fatty acid methyl ester were obtained by the same method as in Example 1 using palm oil, palm kernel oil, and beef tallow, respectively.

[0035]

[Table 3]

From Table 1, Table 2 and Table 3, the following facts became clear. In Examples 1 to 11, the saponification values of the products of the first and fourth times hardly changed, while in Comparative Examples 1 to 3, the fourth time was high, It was found that the catalyst life was suppressed by the method of the present invention. Further, in all Examples, the production amount of by-products such as hydrocarbons tended to decrease in the first to fourth times, whereas in Comparative Examples 1 and 2, there was an increasing tendency. .
From this, it became clear that the production of various by-products was suppressed by the method of the present invention. It was also shown that when the amount of the basic substance added exceeds the range of the method of the present invention, by-products are suppressed, but the catalyst life is significantly reduced (Comparative Example 3).

[0037]

According to the present invention, the catalyst life is not shortened in the hydrogenation reaction of fats and oils or fatty acid esters without pretreatment such as distillation, and the dialkyl ether, alkyl methyl ether, hydrocarbon, etc. Can be suppressed and the hydrogenation reaction of the oil or fatty acid ester can be continued for a suitable period of time.

Claims (5)

[Claims] 1. A method for producing a corresponding higher alcohol by hydrogenating a fat or oil or a fatty acid ester in the presence of a hydrogenation catalyst, wherein a basic substance is added in an amount of 0.1 to 1000 ppm with respect to the fat or the fatty acid ester. A characteristic method for producing higher alcohols. 2. The oil and fat is palm oil, palm oil, palm kernel oil,
The method according to claim 1, which is soybean oil, rapeseed oil, beef tallow, lard, fish oil, or hydrogenated oil thereof. 3. A fatty acid ester obtained by transesterifying coconut oil, palm oil, palm kernel oil, soybean oil, rapeseed oil, beef tallow, lard, or fish oil with an alcohol having 1 to 18 carbon atoms,
Alternatively, carboxylic acid obtained from palm oil, palm oil, palm kernel oil, soybean oil, rapeseed oil, beef tallow, lard, or fish oil is esterified with an alcohol having 1 to 18 carbon atoms. Item 2. The manufacturing method according to Item 1. 4. The basic substance is a hydroxide, bicarbonate, or carbonate of an alkali metal or an alkaline earth metal, an alcoholate having a hydrocarbon group of 1 to 18 carbon atoms, or a carbon atom of 1 to 18 carbon atoms. The method according to any one of claims 1 to 3, which is an amine having a hydrogen group or ammonia. 5. The production method according to claim 1, wherein the hydrogenation catalyst is a copper-based catalyst.