JPH09279179A - Production of fatty acid from wax ester - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for producing a fatty acid having high purity from a wax ester, especially a process for producing highly pure gondoic acid from jojoba oil with a simple process. SOLUTION: A wax ester is hydrolyzed, partially neutralized and dissolved in a polar solvent. The solution is cooled, the precipitated crystal of an acidic salt of a fatty acid is collected and decomposed with an acid and the product is distilled to obtain a fatty acid. The distilled fatty acid is (A) dissolved together with urea in an organic solvent and cooled, the precipitated crystal is separated and removed an (B) water is added to the obtained organic solvent solution and the formed oil layer is separated and recovered or (C) urea dissolved in the obtained organic solvent solution, the solution is cooled, the precipitated crystal is collected, water is added to the crystal and the formed oil layer is separated and recovered and (D) the oil layers are dissolved in a polar solvent and partially neutralized, the solution is cooled and the precipitated fatty acid acidic salt is collected and decomposed with an acid.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a fatty acid from wax ester, and more particularly to a method for producing gondoic acid from jojoba oil.

[0002]

2. Description of the Related Art Jojoba oil contains about 35% by weight of gondoic acid. This gondoic acid is cis-11
-It is known that eicosenoic acid has many excellent properties such as physical, chemical and physiological properties in recent years, and it is expected to be applied to fields such as pharmaceuticals and cosmetics. There is.

Jojoba oil is not an ordinary fat (triglyceride) but an ester (wax ester) with higher alcohol. When triglyceride is hydrolyzed, the constituent fatty acids and glycerin have low compatibility, so it is easy to separate the two, but it is easy to separate the fatty acids and higher alcohols, which are the constituents of wax ester. is not. In particular, in the case of jojoba oil, the hydrocarbon chain length of higher alcohols and fatty acids is close and the difference in physical properties is small, so it is not easy to separate the two, and it is also easy to separate gondoin acid and other fatty acid species. is not.

Conventionally, in order to separate the fatty acid and the higher alcohol in the wax ester, the wax ester is hydrolyzed, and the higher alcohol and the fatty acid alkali metal salt (JP-A-50-151848, JP-A-2-56442), fatty acid alkaline earth metal salts (JP-A-51-60).
No. 207, JP-A-4-266998) or fatty acid lower alcohol ester (JP-A-6-21218).
No. 7), a method of separating the mixture by liquid-liquid or solid-liquid extraction is known.

[0005]

However, the method disclosed in JP-A-50-151848 has a drawback that the emulsifying property of the saponified product is large and separation is difficult. Further, the method disclosed in JP-A-6-212187 is a method applicable only to rice wax ester having a higher alcohol having a carbon number of 24 or more as a main component, which crystallizes at room temperature, and the like. Fatty acids and higher alcohols
This is an unsuitable method for jojoba oil containing less than 22 carbon atoms.

Further, JP-A-2-56442, JP-A-51-60207 and JP-A-4-26699.
Also in the method disclosed in JP-A-8, although separation of fatty acid and higher alcohol is possible, separation by fatty acid species is almost impossible. Therefore, when jojoba oil is used as a raw material, the purity of gondoinic acid remains at about 70% by weight only by removing the higher alcohol, and more steps are required to obtain high-purity gondoinic acid. necessary.

In view of this point, the present invention aims to provide a method for producing high-purity fatty acid from wax ester, particularly a method for producing high-purity gondoin acid from jojoba oil in a simple process. There is.

[0008]

Means for Solving the Problems The inventors of the present invention have made extensive studies on the above object, and as a result, after hydrolysis of wax ester, partial neutralization with acid or alkali,
This is dissolved in a polar solvent and cooled, the crystals of the precipitated acid salt of fatty acid are collected, and after acid decomposition,
It was found that highly purified gondoinic acid can be obtained from highly purified high-purity fatty acid, especially jojoba oil, by distillation.

The distilled fatty acid obtained by this method was dissolved in an organic solvent together with urea and cooled, the precipitated crystals were separated and removed, and the obtained organic solvent solution was mixed with water. The oil layer is separated and collected, or urea is added again to the organic solvent solution to dissolve and cool, the precipitated crystals are separated, and water is added to this to separate and collect the resulting oil layer,
The oil layer thus separated and recovered is dissolved in a polar solvent and partially neutralized and then cooled, and the precipitated acid salt crystals of the fatty acid are separated and acid-decomposed to further purify gondoic acid. I found that

That is, according to the present invention, after wax wax ester is hydrolyzed, it is partially neutralized, dissolved in a polar solvent and cooled, and the precipitated acid salt of a fatty acid salt is separated and acid decomposed. Then, the fatty acid after distillation obtained by this method is dissolved in an organic solvent together with (a) urea and then cooled to separate precipitated crystals. (B) Water was added to the resulting organic solvent solution to separate and collect the resulting oil layer, and (c) this oil layer was dissolved in a polar solvent to partially neutralize and then cooled,
A method for producing a fatty acid, characterized in that crystals of an acid salt of the precipitated fatty acid are collected and acid-decomposed (claim 2), in which, instead of the step (b), (d) is obtained. Urea was added to the organic solvent solution to dissolve and then cooled, and the precipitated crystals were separated, and water was added to this to separate and collect the resulting oil layer, which led to the step (c). The present invention relates to a method for producing a fatty acid (claim 3).

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION In the following, as an embodiment of the present invention, a method of using jojoba oil as wax ester to obtain gondonic acid of higher purity will be described.

In the present invention, first, jojoba oil is hydrolyzed into fatty acids and higher alcohols which are constituents. The hydrolysis can be performed by using a method such as high-pressure hydrolysis, saponification decomposition, and enzymatic decomposition. The alkali used for saponification decomposition includes hydroxides and carbonates of sodium, potassium, lithium, ammonia and the like. The amount of alkali used is 0. 1 of the fatty acid equivalent contained in jojoba oil.
It is 8 to 2 times, preferably 1.0 to 1.5 times.

After the hydrolysis, the produced fatty acid is partially neutralized with an acid or an alkali to form an acid salt. As the alkali used for partial neutralization, the same alkali as used for saponification and decomposition can be used. When the hydrolysis is carried out by saponification, it is partially neutralized with an acid to give an acid salt. As the acid,
Inorganic acids such as sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid, phosphorous acid, hypophosphorous acid, carbonic acid and boric acid, and organic acids such as acetic acid, oxalic acid, malonic acid, succinic acid, malic acid, tartaric acid and citric acid Can be used. The partial neutralization can also be performed after the hydrolysis and then the dissolution in a polar solvent.

The neutralization rate is 30 to 60% by weight, preferably 40 to 50% by weight, based on the fatty acid component in jojoba oil. When the neutralization rate is less than 30% by weight, the yield of gondolic acid is reduced. Further, when it exceeds 60% by weight, the purity of gondoic acid decreases, and the crystalline state of the crystallized acid salt of the fatty acid deteriorates, making filtration difficult,
Separation of high-grade alcohol becomes insufficient.

The thus partially neutralized hydrolyzate is dissolved in a polar solvent and cooled, and the precipitated acid salt crystals of fatty acid are collected. As a result, the high-grade alcohol dissolved in the liquid
Are separated and removed. At the same time, fatty acid components other than gondoic acid are separated and removed, and a trace amount of impurities are also removed. In the case of partial neutralization with an acid after saponification and decomposition, it is desirable to remove salts generated by the reaction between the alkali used for saponification and the acid used for neutralization by filtration prior to the main treatment. . This improves the crystalline state of the acid salt in the above treatment.

Examples of the polar solvent used in the above treatment include lower alcohols such as methanol, ethanol, n-propanol and isopropanol, acetone, acetonitrile, water and a mixed solvent thereof. Can be mentioned. The amount of the polar solvent to be used cannot be unconditionally determined depending on the target purity, the yield, the setting of the number of crystallizations, etc., but it is preferably 2 to 20 times the weight of the raw jojoba oil. If it is less than 2 times by weight, the separation of high-grade alcohol will be insufficient and 2
When the amount is more than 0 times by weight, the concentration of fatty acid becomes low and the yield decreases, which is not preferable.

The cooling temperature is preferably 0 to 20 ° C. 20
If the temperature exceeds ℃, the amount of acid salt deposited is small, which is disadvantageous.
The lower is the purity of gondolic acid. After the precipitation of crystals is started, the cooling rate is preferably 1 ° C./minute or less. If it exceeds 1 ° C./min, the crystalline state becomes poor and it becomes difficult to separate the crystal and the solution.

When the operation of re-dissolving the collected acid salt crystals in a polar solvent again and cooling and collecting the precipitated acid salt crystals is repeated, higher alcohols, fatty acids other than gondoic acid, trace amounts Further impurities can be removed.

Next, the thus separated crystals of the acid salt are acid-decomposed, that is, an acid is added to decompose crystals of gondoic acid, which is a free fatty acid. The same acid as that used for partial neutralization can be used. The amount of the acid used is at least equivalent, preferably at least 1.2 equivalent of the base forming the acid salt. After acid decomposition,
The above acid contained in gondoic acid is removed by washing with water. At that time, if a small amount of polybasic acid such as oxalic acid or citric acid is added, emulsification at the time of washing with water can be prevented, and acid decomposition of the acid salt can be carried out completely.

After this acid decomposition, distillation is carried out to remove the higher alcohol content and trace amounts of impurities remaining in the gondoic acid to obtain a highly pure gondoic acid. Distillation is carried out in an atmosphere of inert gas. The vacuum should be as low as possible and the distillation temperature should be as low as possible. Distillation temperature is 1
When the temperature is 80 ° C. or higher, the remaining higher alcohol reacts with the fatty acid to reform wax ester and is removed as a high boiling point component. This wax ester can be reused as a raw material of the present invention.

In the above-mentioned method of the present invention, as described above, by repeating the operation of redissolving the separated crystals of the acid salt in the polar solvent, cooling and collecting the precipitated crystals of the acid salt, The purity of gondoic acid can be increased. However, in this case, the yield of gondoic acid may decrease. Therefore, in order to avoid this problem and to obtain a higher purity gondoin acid, the following steps (a), (b), and (c) are added, or the step (b) is (d). Instead of the process of (a),
It is desirable to add steps (d) and (c).

In step (a), the distilled fatty acid obtained by the above method is dissolved in an organic solvent together with urea and then cooled, and the precipitated crystals are separated and removed. Cooling temperature is 30 ℃
The following is preferably 20 to 0 ° C. The crystal is an adduct of urea with a monoene fatty acid having a carbon number higher than that of saturated fatty acid or gondoic acid. The crystals are separated and removed by usual means such as filtration and centrifugation. Usually, this step is sufficient for one operation, but it may be repeated twice or more in order to enhance the efficiency of removing crystals.

Examples of the organic solvent include methanol and ethanol.
Lower alcohols such as phenol, n-propanol, and isopropanol, acetone, acetonitrile, and a solvent obtained by mixing these are used. Although the amount of the organic solvent used cannot be unconditionally determined depending on the target purity, yield, setting of the number of crystallizations, etc., it is preferably 0.5 to 10 times the weight of the fatty acid. If it is less than 0.5 times by weight, the amount of urea dissolved will decrease, and the removal of monoene unsaturated fatty acid having a higher carbon number than gondoic acid will be insufficient, and if it exceeds 10 times by weight, the concentration of fatty acid will be low and the production efficiency will be low. descend.

The amount of urea used can be appropriately set depending on the fatty acid composition, target purity, yield, crystallization temperature, amount of solvent and the like. 3 to the total amount of saturated fatty acids contained in fatty acids and monoene unsaturated fatty acids having a carbon number higher than that of gondoic acid
30 times by weight is preferable. When it is less than 3 times by weight, the removal of saturated fatty acids and the above-mentioned monoene unsaturated fatty acids becomes insufficient, and when it is more than 30 times by weight, the yield of gondoic acid decreases.

In the step (b), water is added to the organic solvent solution obtained in the step (a) to separate and collect an oil layer produced. The oil layer is a mixture of fatty acids, which is recovered by static separation or centrifugation. The amount of water used is preferably 3 times or more the weight of the organic solvent solution. At this time, by adding a small amount of polybasic acid such as oxalic acid or citric acid, it is possible to prevent emulsification during washing with water.

In the step (d), instead of the step (b), urea is added again to the organic solvent solution obtained in the step (a) to dissolve it by heating and then cooled, and the precipitated crystal is separated. Then, water is added to this and the resulting oil layer is separated and collected. The crystal is an adduct of gondoic acid and urea, which is separated by a usual means such as filtration and centrifugation. When water is added to this, it decomposes and gondoic acid is separated and collected as an oil layer.

The amount of urea used can be appropriately set according to the fatty acid composition in the organic solvent solution obtained in the step (a), target purity, yield, crystallization temperature, amount of solvent and the like. Usually, 3 to 20 times by weight of fatty acid is preferable. If it is less than 3 times by weight, the yield of gondoinic acid will decrease, and if it is more than 20 times by weight, fatty acids other than gondoinic acid will crystallize as urea adducts and the purity of gondoinic acid will decrease.

In step (c), the oil layer separated and collected in step (b) or (d) is dissolved in a polar solvent, partially neutralized and cooled, and the precipitated acid salt crystals of fatty acid are collected. Then, gondoin acid is obtained by acid decomposition, and the operation here is almost the same as the above-mentioned method before the step (a) is added.

As the polar solvent, the same ones as described above can be used, and the amount to be used cannot be unconditionally determined depending on the target purity, yield, number of crystallizations, etc., but is 2 to 10 times the weight of the fatty acid. preferable. If it is less than 2 times by weight, the purity of gondolic acid is lowered, and if it is more than 10 times by weight, the concentration of gondonic acid is low and the production efficiency is lowered. As the alkali for partial neutralization, the same ones as described above can be used, and the neutralization rate is 30 to 60% by weight, preferably 40 to 50% by weight based on the fatty acid component. If it is less than 30% by weight, the yield of gondoinic acid is lowered, and if it exceeds 60% by weight, the crystalline state of the acid salt is deteriorated, filtration becomes difficult, and the purity of gondoinic acid is lowered. The cooling temperature is preferably 20 ° C. or lower. 20 ° C
If it exceeds, the amount of the acid salt deposited will decrease.

By repeating this step (c), fatty acids other than gondoic acid and trace amounts of impurities can be further removed. The gondoic acid thus obtained may be used as the final product as it is, or may be further purified by a method such as distillation, molecular distillation or adsorption to obtain the final product.

The gondoic acid thus obtained is
Highly pure, colorless and odorless, does not contain trace impurities such as oxidation products that cause deterioration, has excellent stability to heat, oxygen and chemicals, and is highly safe for living organisms. It has characteristics such as physical properties peculiar to gondoic acid such as various crystal polymorphisms, and can be used in a wide range of fields such as pharmaceuticals, cosmetics, and biochemicals.

In the above description, jojoba oil is used as wax ester, and a method for obtaining gondonic acid from this is described. As wax wax, in addition to jojoba oil, pine whale oil, orange rathus oil ─ Oil etc. can be used. With these wax esters, oleic acid, which is the main component of fatty acids, can be produced in high purity by the same method as described above.

[0033]

EXAMPLES Next, as examples of the present invention, a method for producing high-purity gondoin acid from jojoba oil will be described and described more specifically.

Example 1 To 1,500 g of refined jojoba oil (saponification number: 92.2), 2,000 g of methanol and 246.5 g of a 48% by weight aqueous sodium hydroxide solution (1.2 times the fatty acid equivalent) were added. ,
After stirring under reflux at 65 ° C. for 3 hours to hydrolyze, 174.9 g of 36% by weight hydrochloric acid aqueous solution (0.5 times the fatty acid equivalent) was dissolved in 500 g of methanol.
The methanol solution was added dropwise over 30 minutes for partial neutralization.

Next, 2,000 g of methanol was added, the solution was heated to 60 ° C., and then stirred to 0.5.
The mixture was cooled to 7 ° C at a cooling rate of ° C / min, and 540 g of precipitated acid salt crystals of fatty acid were collected by suction filtration. To the crystals was added 1,500 g of a 5% by weight aqueous citric acid solution,
It was heated to 0 ° C. and acid-decomposed. The obtained oil layer (free fatty acid) was thoroughly washed with a 0.1% by weight citric acid aqueous solution, and then dehydrated to recover 292 g of crude gondonic acid (acid value 149.7, saponification value 155.4). This was distilled under nitrogen gas blowing at 1-2 mmHg and 200-250 ° C. to obtain 142 g of high-purity gondoic acid (A).

Example 2 A methanol solution of a fatty acid acid salt after partial neutralization obtained by the same operation as in Example 1 was suction filtered to recover a filtrate,
To this was added 2,000 g of methanol, and the mixture was cooled to 5 ° C. at a cooling rate of 0.4 ° C./min while stirring to collect 687 g of precipitated fatty acid acid salt crystals. 1,500 g of a 5 wt% hydrochloric acid aqueous solution was added thereto, and the mixture was heated to 80 ° C. for acid decomposition. The obtained oil layer was thoroughly washed with a 0.05 wt% citric acid aqueous solution and then dehydrated to recover 351 g of crude gondoinic acid (acid value 150.9, saponification value 154.8). This is blown with nitrogen gas, 1-2 mmHg, 200
High-purity gondoin acid (B) 1 distilled at ~ 250 ° C
72 g were obtained.

Example 3 1,500 g of purified jojoba oil was heated to 250 ° C. in a pressure vessel, steam of 60 kg / cm ² was blown therein, and the reaction was carried out for 3 hours to obtain a hydrolyzate (acid value 89.4) 1. 545 g were obtained. This hydrolyzate was dissolved in 4,275 g of methanol and heated to 50 ° C., then anhydrous sodium hydroxide 4
9.2 g (0.5 times the fatty acid equivalent) dissolved in 225 g of water (sodium hydroxide concentration 18% by weight) was added and dissolved by heating at 60 ° C. to form a homogeneous solution, which was stirred for 0.5 After cooling to 5 ° C. at a cooling rate of ° C./min, filtration was performed to obtain 505 g of a fatty acid acid salt crystal.

Next, 1,500 g of a 5 wt% phosphoric acid aqueous solution was added to the crystals, and the mixture was heated to 80 ° C. for acid decomposition. The obtained oil layer was thoroughly washed with a 0.1% by weight citric acid aqueous solution and then dehydrated to obtain crude gondoic acid (acid value 149.7,
280 g of a saponification number of 156.0) was obtained. This was distilled under a nitrogen gas blow at 1-2 mmHg and 200 to 250 ° C. to obtain 133 g of high-purity gondoic acid (C).

Example 4 515 g of crystals of an acid acid salt of a fatty acid obtained by the same procedure as in Example 3 were dissolved in 2,060 g of methanol under heating, and a cooling rate of 0.6 ° C./min was added while stirring. After cooling to 5 ° C. and filtering, 245 g of acid acid salt crystals of fatty acid were obtained. To this crystal was added 900 g of a 5 wt% hydrochloric acid aqueous solution, and 8
It was heated to 0 ° C. and acid-decomposed. The obtained oil layer was thoroughly washed with a 0.1 wt% citric acid aqueous solution and then dehydrated to give crude gondoinic acid (acid value 165.1, saponification value 168.3) 1
47 g were obtained. Blowing this under nitrogen gas, 1-2mmH
g, and distilled at 200 to 250 ° C. to obtain 88 g of high-purity gondoin acid (D).

Comparative Example 1 3,000 g of refined jojoba oil (saponification number: 92.2) and an aqueous solution of sodium hydroxide 387 g (1.5 equivalents) 2,40
0 g was added, and the mixture was hydrolyzed by saponification reaction at 160 ° C. for 6 hours under pressure in a pressure vessel. Next, 10.5 kg of ethyl acetate and 7 parts of calcium chloride dihydrate were added to the hydrolyzate.
An aqueous solution prepared by dissolving 14 g (1.5 equivalents) in 3,000 g of water was added, and the mixture was stirred at 50 ° C. for 30 minutes to convert sodium soap into calcium soap (metal soap) by a metathesis reaction.

Then, the reaction product was allowed to stand at 20 ° C. for one day to separate into an organic solvent layer, an intermediate layer and an aqueous layer. This 3
The layers were separated by decantation and filtration. Aqueous hydrochloric acid was added to the intermediate layer metal soap to adjust the pH to 3.2, the aqueous layer was separated, the oil layer was washed with water to remove hydrochloric acid, and then dehydrated to obtain 1,462 g of a fatty acid mixture. Blowing this under nitrogen gas, 1-3mmHg, 200-250
Distillation was carried out at 0 ° C. to obtain 1,316 g of a fatty acid mixture (E) containing gondoic acid.

Comparative Example 2 In the same manner as in Example 1, the purified jojoba oil was hydrolyzed with an alkali. Dissolve this in 2,000 g of methanol and stir at 42 ° C at a cooling rate of 0.3 ° C / min while stirring.
Crystals precipitated by cooling
g was collected. 5% by weight of an aqueous citric acid solution 3,
000 g was added and the mixture was heated to 80 ° C. for acid decomposition. The obtained oil layer was thoroughly washed with a 0.1% by weight aqueous citric acid solution and then dehydrated to obtain 433 g of a mixture (F) of a fatty acid and a higher alcohol.

High-purity gondoin acids (A) to (D) obtained by the methods of Examples 1 to 4 and final products (E) and (F) obtained by the methods of Comparative Examples 1 and 2 , Yield, fatty acid composition and quality characteristics (acid value, saponification value, hydroxyl value,
The iodine value and melting point) were examined. The results are shown in Table 1 (Examples 1 to 4) and Table 2 (Comparative Examples 1 and 2). Table 2 also shows the fatty acid composition and quality characteristics of the raw jojoba oil.

The fatty acid composition was determined by gas chromatography using a capillary column after fatty acid was methyl esterified. In the table, "C20: 1 ω
`` 9 '' is gondoic acid, `` C20: 1 isomer '' is its isomer, and other fatty acids are represented by the number of carbon atoms and the number of unsaturated carbon-carbon bonds, for example, `` C16: 0 '' is C16 saturated fatty acid (palmitic acid), also "C18: 1"
Means that it is a C18 monoene unsaturated fatty acid (oleic acid).

[0045]

[0046]

As is clear from the results of Tables 1 and 2, according to the methods of Examples 1 to 4, the higher alcohol content can be almost completely removed from the components produced by the hydrolysis of the raw jojoba oil. With about 9 without forming isomers
It can be seen that a highly pure gondoic acid of 3 to 94% by weight can be obtained. On the other hand, in the method of Comparative Example 2, it is clear from the hydroxyl value that it is a mixture of fatty acid and higher alcohol, and also in the method of Comparative Example 1, the hydroxyl value is high and the higher alcohol is higher. In addition, in Comparative Examples 1 and 2, the purity of gondoic acid is as low as about 72% by weight, which is almost the same as that of the raw jojoba oil.

Example 5 1,340 g of gondoic acid (C) obtained in Example 3 and 1,059 g of urea were dissolved in 9.38 kg of methanol and cooled to 15 ° C., and the precipitated crystals were sucked. It was separated and removed by filtration. The filtrate was 1% by weight aqueous citric acid solution 35.
3 Kg was added, and the mixture was heated to 50 ° C., stirred, and then allowed to stand for layer separation, and gondoic acid (purity 94.4% by weight, acid value 180.
6) 1,203 g was obtained.

This gondoinic acid and sodium hydroxide 7
7.4 g (50% equivalent of the acid value of gondoic acid) was added to water 8
What was dissolved in 3.8 g (sodium hydroxide concentration 48% by weight) was mixed with 6.02 kg of methanol and dissolved by heating, and cooled to 5 ° C with stirring at a cooling rate of 0.5 ° C / min. After that, 962 g of crystals of an acid salt of gondoic acid was collected by suction filtration. Add 5 wt% hydrochloric acid aqueous solution to this.
73 kg was added, and the mixture was heated while being acid-decomposed, and the obtained oil layer was thoroughly washed with a 0.1 wt% citric acid aqueous solution and then dehydrated, and gondoic acid (G) (purity 99.2 wt%) 8
18 g was obtained. While blowing this with nitrogen gas, 1 mmHg,
High-purity gondoinic acid (H) by distillation below 250 ° C
736 g was obtained.

Example 6 1,355 g of gondoic acid (C) obtained in Example 3 and 1,070 g of urea were dissolved in 9.49 Kg of methanol and cooled to 15 ° C., and the precipitated crystals were sucked. It was separated and removed by filtration. 2.85 kg of urea was added to the filtrate and dissolved by heating, and the mixture was cooled to 15 ° C, and then precipitated crystals 3,98
4 g was collected by suction filtration. To this crystal, 12.0 kg of a 1% by weight citric acid aqueous solution was added, and the mixture was heated to 50 ° C. and stirred, and then the layers were allowed to stand, and 924 g of gondoic acid (purity 95.6% by weight, acid value 180.7) was added. Obtained.

This gondoinic acid and sodium hydroxide 5
9.5 g (50% equivalent of the acid value of gondoic acid) was added to water 6
What was dissolved in 4.5 g (sodium hydroxide concentration 48% by weight) was mixed with 4.62 kg of methanol and dissolved by heating, and cooled to 5 ° C with stirring at a cooling rate of 0.4 ° C / min. After that, 739 g of crystals of an acid salt of gondoic acid was filtered off. To this, 5.17 kg of a 5 wt% hydrochloric acid aqueous solution was added, and the mixture was heated to 80 ° C. for acid decomposition, and the resulting oil layer was added to 0.1
After thoroughly washing with a wt% citric acid aqueous solution, dehydration,
628 g of gondoic acid (purity 99.5% by weight) was obtained.
This was distilled under nitrogen gas blowing at 1 mmHg and 250 ° C. or lower to obtain 565 g of high-purity gondoinic acid (I).

Example 7 Gondoic acid (G) obtained in the same manner as in Example 5
571 g (purity 99.2% by weight, acid value 180.7),
Sodium hydroxide 36.8 g (5 of acid value of gondoic acid
(0% equivalent) dissolved in 39.9 g of water (sodium hydroxide concentration 48% by weight) was added to 4.00 Kg of methanol to dissolve by heating, and after cooling to 5 ° C. with stirring,
457 g of crystals of acid salt of gondoic acid were filtered off. 5.18 kg of a 5 wt% hydrochloric acid aqueous solution was added to this crystal, and the temperature was 80 ° C.
The resulting oil layer was sufficiently washed with a 0.1% by weight aqueous solution of citric acid and then dehydrated to obtain 388 g of high-purity gondoic acid (J).

The fatty acid composition of the high-purity gondoin acids (H) to (J) obtained by the methods of Examples 5 to 7 was examined in the same manner as described above. The results, together with the final yield from jojoba oil, are shown in Table 3 below.

[0054]

As is clear from the results of Table 3, Example 3
It can be seen that by further reacting the gondoinic acid obtained by the method 1) with urea, an extremely high-purity final product having a purity of the gondoinic acid of 99% by weight or more can be obtained.

[0056]

As described above, according to the method of the present invention,
Using wax ester as a raw material, a high-purity fatty acid, which was difficult to prepare by conventional technology, was obtained from jojoba oil by a simple process. It can be manufactured.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication C07C 57/03 2115-4H C07C 57/03 C11C 1/08 C11C 1/08 3/00 3/00 // C11B 7/00 C11B 7/00

Claims (3)

[Claims] 1. After hydrolyzing a wax ester,
A method for producing a fatty acid, which comprises partially neutralizing, dissolving this in a polar solvent and cooling, collecting crystals of the precipitated acid salt of fatty acid, acidolyzing and distilling. 2. The distilled fatty acid obtained by the method of claim 1 is dissolved in an organic solvent together with (a) urea and then cooled, and the precipitated crystals are separated and removed, and (b) the obtained organic solvent. Water was added to the solution to separate and collect the resulting oil layer, and (c) this oil layer was dissolved in a polar solvent to partially neutralize and then cooled,
A method for producing a fatty acid, characterized in that crystals of an acid salt of a precipitated fatty acid are collected and acid-decomposed. 3. The method according to claim 2, wherein in place of the step (b), (d) urea is added to the obtained organic solvent solution and dissolved, and then cooled, and the precipitated crystal is separated, A method for producing a fatty acid, characterized in that water is added to this to separate and collect the resulting oil layer, and this is led to the step (c).