JPH0657675B2 - Process for producing polyalkylene glycol monooleate - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing polyalkylene glycol monooleate.

[Conventional technology]

Polyalkylene glycol monooleate is widely used for applications such as emulsifiers and dispersants. It is used for esterification reaction of oleic acid and polyalkylene glycol, transesterification reaction of methyl oleate and polyalkylene glycol, or alkali catalyst It is prepared by adding an alkylene oxide to oleic acid in the presence.

[Problems to be solved by the invention]

However, since the conventional polyalkylene glycol monooleate is not suitable for the production method, the content of the monoester is about 70% by weight even if it is called as the polyalkylene glycol monoester, and the monoester, diester, polyester It is a ternary mixture of alkylene glycols and was unsuitable for applications requiring solubilizers or emulsifications close to solubilization. In addition, conventional oleic acid uses distillation as the final step.However, not only impurities that are within the same boiling range as oleic acid, but also many impurities that have some vapor pressure in the oleic acid fraction can be obtained by simple distillation. Therefore, the effect of separating impurities is insufficient. Further, since the distillation is performed at a high temperature, decomposition of unsaturated fatty acid due to heat, deterioration of the substrate such as polymerization and isomerization occur, and a low boiling point component is mixed in the distillate of oleic acid, which has generated a low boiling point component due to thermal decomposition of impurities As a result, the quality of oleic acid deteriorates, and only colored and odorous oleic acid can be obtained. Moreover, the obtained oleic acid has a strong tendency to be further colored and smelled when heated. Conventional polyalkylene glycol oleate uses such oleic acid as a raw material and is heated during the production of ester, so the obtained product has coloring and odor, and moreover over time or by heating. The color and odor became more intense, and there was a problem in using it in medicines and cosmetics.

[Means for solving problems]

The applicant previously applied for a method for producing oleic acid, which is colorless and odorless and has excellent stability such as stability against heat and oxidation and skin irritation (Japanese Patent Application No. 59-119170).

The present inventors add about 1 mol of ethylene oxide or propylene oxide to the oleic acid produced by this method in the presence of a specific catalyst, and then add α-olefin oxide or tetrahydrofuran in the presence of a Lewis acid catalyst. As a result, they have found that a highly pure polyalkylene glycol monooleate, which is almost colorless and odorless and has good stability, is obtained, and the present invention has been completed.

Oleic acid used in the present invention, (a) the fatty acid mixture containing oleic acid and urea are dissolved in an organic solvent and then cooled to remove the precipitated crystals, and (b) the fatty acid contained in the organic solvent solution. Oleic acid is obtained by partially saponifying the mixture, then recrystallizing the crystals, and (c) acid-decomposing the obtained crystals.

The step (a) is a step of removing higher saturated fatty acids having 16 or more carbon atoms and monounsaturated fatty acids higher than oleic acid from a fatty acid mixture containing oleic acid, and the resulting organic solvent solution inevitably contains a small amount. Urea remains. When the following step (b) is carried out using this organic solvent solution, residual urea forms an acid salt of oleic acid and an adduct in an appropriate amount to form a hard and free-flowing crystal, and therefore a partially saponified fatty acid mixture The crystalline state is improved and the crystals obtained by recrystallization become easier, and polyunsaturated fatty acids such as linoleic acid, monounsaturated fatty acids lower than oleic acid, lower saturated fatty acids and other impurities can be removed efficiently. As it can be carried out, highly pure and highly purified oleic acid is produced.

As the fatty acid mixture containing oleic acid used as this raw material, anything containing oleic acid can be used, and olive oil, sesame oil, rice bran oil, soybean oil,
Fatty acids obtained by hydrolyzing fats and oils such as tea seed oil, camellia oil, corn oil, rapeseed oil, palm oil, peanut oil, safflower oil, beef tallow, lard, chicken oil, sheep fat and fish oil, and mixtures thereof. Can be used, and commercially available oleic acid containing impurities can also be used as a raw material. As a matter of course, the higher the content of oleic acid, the more efficiently the highly pure oleic acid can be obtained.

As the organic solvent used in the step (a), lower alcohols such as methanol, ethanol, n-propanol, and isopropanol, and mixed solvents containing these as the main components are used. The amount of the organic solvent used cannot be determined unconditionally depending on the composition of the raw material fatty acid, the target purity and yield, the setting of the number of crystallizations, etc.
Weight times are preferred. If it is less than 0.5 part by weight, the separation effect is lowered, and if it is more than 10 parts by weight, the fatty acid concentration is low and the production efficiency is lowered, which is disadvantageous.

The amount of urea used depends on the composition of the starting fatty acid, the target purity and yield, the crystallization temperature, the amount of solvent, etc., but the saturated fatty acid containing 16 or more carbon atoms contained in the starting fatty acid It is preferably 3 to 50 times by weight the total amount of monounsaturated fatty acids higher than oleic acid. If it is less than 3 times by weight, the removal of saturated fatty acids having 16 or more carbon atoms and monounsaturated fatty acids higher than oleic acid will be insufficient, and if it is more than 50 times by weight, the oleic acid yield will decrease.

In the step (a), a fatty acid mixture containing urea and oleic acid is added to an organic solvent, dissolved by heating, and then gradually cooled, usually at 30 ° C or lower, preferably in the range of 20 to -20 ° C. Saturated fatty acids having 16 or more carbon atoms, monounsaturated fatty acids higher than oleic acid, and the like form adducts with urea and are crystallized. Therefore, the crystals are separately removed by a usual means such as centrifugation.

Normally, (a) step is sufficient for one operation, but carbon number 1
It may be repeated if the separation of saturated fatty acids of 6 or more and monounsaturated fatty acids higher than oleic acid is insufficient.

In the step (b), first, a basic compound such as a hydroxide or carbonate such as lithium, sodium, potassium or ammonia is added to the organic solvent solution of the fatty acid mixture obtained in the step (b) to partially neutralize the solution. Harmonize Oleic acid forms an acid salt by this partial saponification, and when cooled, becomes an acid salt of oleic acid.
The small amount of urea remaining in the step (a) forms an adduct in a suitable amount to form a crystal that easily passes as a whole, and separation of components such as polyunsaturated fatty acids to be removed is easy. The neutralization rate in this case is from 20% of the oleic acid contained to 60% of the total fatty acid mixture, preferably 30% of the oleic acid.
% To 55% of the total fatty acid mixture. If the neutralization rate is less than 20% of oleic acid, the yield of oleic acid obtained is low, and if it exceeds 60% of the total fatty acid mixture, the separation effect is reduced and the crystalline state of the crystallized acid salt of oleic acid is deteriorated. And the purity of the obtained oleic acid decreases.

The temperature for cooling to crystallize the acid salt of oleic acid is 10 to -30 ° C, preferably 5 to -20 ° C. 1
If the temperature is higher than 0 ° C, the yield of oleic acid will decrease, and if it is lower than -30 ° C, the purity of oleic acid will decrease.

The crystals of the acid salt of oleic acid thus formed are separated from the solution containing the polyunsaturated fatty acid by a conventional method.

The crystal of the acid salt of oleic acid can be further improved in purity by repeating recrystallization.

As the solvent used for repeating the recrystallization of the acid salt of oleic acid, methanol, ethanol, isopropanol,
A polar solvent such as n-butanol, isobutanol, acetone, methyl ethyl ketone, diethyl ether, ethyl acetate or acetonitrile, or a mixed solvent containing these is used. In this case, the concentration of the acid salt of oleic acid is 1
0 to 50% by weight, and the cooling temperature is preferably 5 to -20 ° C.

In the step (c), an acid is added to an acid salt of oleic acid to decompose the acid,
This is a step of obtaining oleic acid.

Examples of the acid used for acid decomposition include sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid, phosphorous acid, hypophosphorous acid, carbonic acid, inorganic acids such as boric acid, acetic acid, oxalic acid, malonic acid, succinic acid, malic acid,
Organic acids such as tartaric acid and citric acid can be used. The amount of the acid used is equal to or more than the equivalent of the base forming the acid salt of oleic acid, and preferably 1.2 equivalent or more.

After acid decomposition, the acid used for acid decomposition remaining in oleic acid is removed by washing with water. When a small amount of polybasic acid such as oxalic acid or citric acid is added during the washing with water, emulsification at the time of washing with water can be prevented, and salt decomposition of the acid salt of oleic acid is also completely carried out.

In this way, high-purity oleic acid can be obtained, but in order to remove a trace amount of impurities, it is also possible to carry out an adsorbent treatment or distillation which is usually used for refining fatty acids.

As the adsorbent used for the adsorbent treatment, clay, activated clay,
Activated carbon, silica gel, alumina, silica-alumina, ion exchange resins, synthetic adsorbents and the like are available, and they are used alone or as a mixture. The amount of the adsorbent used varies depending on the degree of purification of oleic acid and the target quality, but is 0.1 to 5% by weight with respect to oleic acid. The temperature of the adsorbent treatment is not less than the melting point of oleic acid, preferably 30 to 80 ° C.
The processing time is about 20 minutes to 2 hours.

Distillation is performed under reduced pressure in an atmosphere of an inert gas under the conditions usually used for distillation of oleic acid. The vacuum should be as low as possible and the distillation temperature should be as low as possible.

That is, the present invention, in the oleic acid obtained by this method,
After adding 0.9 to 1.1 mol of ethylene oxide or propylene oxide to 1 mol of oleic acid using a tertiary amine or quaternary ammonium salt as a catalyst,
A method for producing a polyalkylene glycol monooleate, which comprises adding α-olefin oxide or tetrahydrofuran in the presence of a Lewis acid catalyst.

Ethylene oxide or propylene oxide to which a tertiary amine or quaternary ammonium salt is added as a catalyst is
They may be used alone or in combination.

As the tertiary amine used as a catalyst, triethylamine, tripropylamine, tributylamine, triisoamylamine, triethanolamine, pyridine, N-
Methylpiperidine, N-ethylpiperidine, N, N'-
There are dimethylpiperazine, N, N′-diethylpiperazine and the like, and as the quaternary ammonium salt, tetramethylammonium halide, tetraethylammonium halide, tetrapropylammonium halide, tetrabutylammonium halide, methyltriethylammonium halide, methyltripropylammonium halide. , Methyltributylammonium halide, ethyltrimethylammonium halide, ethyltripropylammonium halide, ethyltributylammonium halide, trimethylbenzylammonium halide, triethylbenzylammonium halide, tripropylbenzylammonium halide, tributylbenzylammonium halide, N-methylpyridinium halide, N -Ethylpyridy There are um halides, N-propylpyridinium halides, N-dodecylpyridinium halides, N-hexadecylpyridinium halides, N-benzylpyridinium halides, and the like, where the halides are chloride, bromide, iodide, etc., and are used for addition reaction of epoxy compounds. A catalytically effective tertiary amine or quaternary ammonium salt is used.

As the Lewis acid catalyst, those which are effective for the addition reaction of α-olefin oxide such as boron trifluoride, aluminum chloride, tin tetrachloride, antimony pentachloride, etc. are used.

As α-olefin oxide, ethylene oxide,
Propylene oxide, butylene oxide, isobutylene oxide, α-olefin oxide having 12 to 18 carbon atoms, styrene oxide and the like are used and may be added in combination with tetrahydrofuran. In the case of co-adding two or more kinds of α-olefin oxide or in the case of co-adding α-olefin oxide and tetrahydrofuran, they may be added blockwise or randomly.

The oleic acid used in the present invention is limited to the oleic acid produced by a specific method, because the oleic acid has a high purity, is colorless and odorless, and further has good stability, and is colored during the reaction. This is because it produces almost no odor.

The reaction molar ratio between oleic acid and ethylene oxide or propylene oxide is limited because when a tertiary amine or quaternary ammonium salt is used as a catalyst, the addition reaction mainly occurs up to about 1.1 moles of addition. This is because the esterification reaction between monooleate and oleic acid and the transesterification reaction of monooleate hardly occur.

In the addition reaction of α-olefin oxide or tetrahydrofuran using the Lewis acid catalyst in the next step, the addition reaction mainly occurs and the transesterification reaction of monooleate hardly occurs.

This gives polyalkylene glycol monooleate in high purity.

Next, the manufacturing method of the present invention will be specifically described.

First, 0.001 to 0.5 mol, preferably 0.003 to 0.05 mol of a tertiary amine or quaternary ammonium salt is added as a catalyst to 1 mol of oleic acid, and the air in the space is replaced with nitrogen gas. Replace with an inert gas such as. Then 4
0 ~ 150 ℃, preferably 50 ~ 110 ℃, pressure 10Kg
/ Cm ² G or less, preferably 5 kg / cm ² G or less,
0.9-1.1 mol of ethylene oxide or propylene oxide is added. In this case, if the amount of the catalyst is smaller than the above, the reaction rate is slow, and if the amount is large, it becomes difficult to remove the catalyst, and coloring or odor is likely to occur. When the reaction temperature is lower than the above, the reaction rate is slow, and when it is too high, coloring or odor is likely to occur. After this, the tertiary amine or quaternary ammonium salt of the catalyst may or may not be removed.

Next, it is 0.0 with respect to 1 mol of the obtained monooleate.
01-0.5 mol, preferably 0.003-0.3 mol of a Lewis acid catalyst is added and the air in the space is replaced with an inert gas such as nitrogen gas. Then 10 to 70 ° C., preferably 20 to 50 ° C., pressure 10 kg / cm ² G or less, preferably 5 K
After adding a predetermined amount of α-olefin oxide or tetrahydrofuran under the condition of g / cm ² G or less, the Lewis acid catalyst can be removed to obtain polyalkylene glycol monooleate. The amount of the Lewis acid catalyst used may be lower when the tertiary amine or quaternary ammonium salt which is the catalyst in the previous step is removed than when it is not removed. When the amount of the Lewis acid catalyst used is less than the above amount, the reaction rate is slow, and when the amount is large, coloring and odor are likely to occur. When the reaction temperature is lower than the above, the reaction rate is slow, and when it is higher, coloring and odor are likely to occur. The Lewis acid catalyst after the reaction is removed by washing with water or by separating the salt produced by neutralization. Washing with water may be carried out by dissolving the reaction product in a solvent which is incompatible with water, such as hexane, benzene, toluene and ethyl acetate.

〔The invention's effect〕

According to the method of the present invention, polyalkylene glycol monooleate, which has almost no coloring and odor and is excellent in stability, can be obtained in high purity.

〔Example〕

 The present invention will be described with reference to Examples, Comparative Examples and Test Examples.

Example 1 12.42 Kg of urea was added to 40 Kg of methanol and dissolved by heating, and then 10 Kg of distilled fatty acid of Oreet safflower oil heated at 50 ° C. was added and dissolved. While stirring, 1
The mixture was cooled to 0 ° C., and the resulting crystals were centrifuged and the liquid 52.
12 kg was obtained. (Fatty acid content 6.52 Kg, acid value 198.
5, urea content 2.32 kg) was obtained. To this solution was added 5.76 Kg of an aqueous solution containing 415 g of sodium hydroxide (45% equivalent of the fatty acid content) and dissolved, while stirring to -7
After cooling to ℃ and separating, 4.2 acidic salt crystals of oleic acid
7 kg (acid salt content 3.7 kg) was obtained. Aqueous solution containing 930 g of phosphoric acid (1.5 equivalents of acid salt) in the crystals 18.
56 kg was added, and the mixture was heated to undergo acid decomposition. After thoroughly washing the obtained oil layer with a 0.5 wt% aqueous citric acid solution,
After dehydration, 3.56 kg of oleic acid (purity: 99.2%) was obtained.

A mixture obtained by adding 2 g (0.022 mol) of tetramethylammonium chloride to 564 g (2 mol) of the obtained oleic acid was placed in a 3 autoclave, and after replacing with nitrogen gas, the mixture was heated to 90 ° C. and the pressure was adjusted to 0. It was adjusted to 5 kg / cm ² G. Then, 88 g (2 mol) of ethylene oxide was injected under pressure at 80 to 100 ° C. under 5 kg / cm ² G for about 8 hours to react. The reaction was further continued at 90 ° C for 1 hour and then cooled to 20 ° C. Then, 10 g of boron trifluoride ether (0.7 mol) was added and the atmosphere was replaced with nitrogen gas, and then 388 g (8.8 mol) of ethylene oxide was added at 20 to 30 ° C. under 5 kg / cm ² G. The mixture was pressed for about 8 hours for reaction. The reaction was further continued for 1 hour, nitrogen gas was blown thereinto to distill off unreacted ethylene oxide, and then the mixture was neutralized with an aqueous sodium hydroxide solution. The reaction mixture obtained was dissolved in 1.5 Kg of hexane,
It was washed with water 1 at 0 ° C. and left standing to remove the separated aqueous layer. After washing with water 4 times, the volatile matter was removed at 70 ° C. and 2 mmHg or less for 3 hours to obtain 950 g of polyethylene glycol (5 mol) monooleate.

Comparative Example 1 5.6 g in 564 g (2 mol) of commercially available distilled oleic acid
(0.1 mol) of potassium hydroxide was added, the atmosphere was replaced with nitrogen gas, and the temperature was raised to 120 ° C. 120-140
Under the conditions of the temperature of 5 Kg / cm ² or less, 476 g (10.8 mol) of ethylene oxide was added in about 5 hours. Nitrogen gas was blown in to remove unreacted ethylene oxide, and then the mixture was cooled to 50 ° C., neutralized with phosphoric acid, dehydrated, and the produced salt was separated to obtain 960 g of polyethylene glycol (5 mol) monooleate.

Comparative Example 2 Instead of the oleic acid used in Comparative Example 1, 564 g (2 mol) of oleic acid prepared in Example 1 was used and the reaction was carried out under the same conditions as in Comparative Example 1 to obtain 955 g of polyethylene glycol (5 mol). I got monooleate.

Comparative Example 3 Using 564 g (2 mol) of oleic acid used in Comparative Example 1, ethylene oxide was added under the same conditions as in Example 1 to obtain 940 g of polyethylene glycol (5 mol) monooleate.

Test Example 1 The polyethylene glycol monooleate obtained in Example 1 and Comparative Examples 1 to 3 was subjected to the following performance evaluations. The results are shown in Table 1.

1. Composition analysis by gas chromatography.

2. Color, odor and peroxide value immediately after manufacture.

3. Take 150g of sample in a 300ml beaker and
Color, odor and peroxide number after heating at 0 ° C. for 24 hours.

4. Take 150g of sample in a 300ml sample bottle,
The color after sealing and leaving it in a 50 ° C incubator for 3 months,
Odor and peroxide value.

The results of quality evaluation are shown in Table 1. From Table 1, it can be seen that the polyethylene glycol (5 mol) monooleate obtained by the production method of the present invention has high purity, good color and odor, and is stable against heating and aging.

Example 2 A mixture of 564 g (2 mol) of oleic acid prepared in Example 1 and 3 g (0.04 mol) of triethylamine was placed in one autoclave, and nitrogen gas was replaced. Was adjusted to 0.5 Kg / cm ² G. Then, 116 g (2 mol) of propylene oxide was injected under pressure at 80 to 100 ° C. under 5 kg / cm ² G for about 8 hours to cause reaction. After continuing the reaction at 90 ° C. for 1 hour, nitrogen gas was blown in to distill off unreacted propylene oxide, and the mixture was cooled to 50 ° C. Next, it was neutralized with phosphoric acid and washed with water of 1 to remove the separated water.
After washing with water three times, dehydration was carried out at 100 ° C. and 10 mmHg or less for 2 hours, and then 650 g of propylene glycol monooleate was obtained. A mixture of 340 g (1 mol) of propylene glycol monooleate thus obtained and 6.8 g (0.27 mol) of tin tetrachloride was placed in one autoclave and heated to 30 ° C. to perform nitrogen gas replacement. Under the conditions of 30 to 50 ° C. and 5 Kg / cm ² G or less, 290 g (5 mol) of propylene oxide is reacted for 8 hours, the unreacted propylene oxide is distilled off, and then neutralized with sodium hydroxide. Wash 3 times with water,
After dehydration at 100 ° C. for 10 hours at 10 mmHg or less, 600 g of polypropylene glycol (6 mol) monooleate was obtained.

Comparative Example 4 282 g (1 mol) of oleic acid purified by simple distillation, polypropylene glycol (average degree of polymerization 6) 36
A mixture of 6 g (1 mol) and 2 g of paratoluenesulfonic acid was heated to 130 ° C. and heated to 130 to 150 in a nitrogen gas stream.
After carrying out the ester reaction for 10 hours at a temperature of 10 ° C. and 10 mmHg or less, the mixture was neutralized with an aqueous solution of sodium hydroxide, and Example 2 was used.
It was washed with water, dehydrated and filtered in the same manner as above to obtain 590 g of polypropylene glycol (6 mol) monooleate.

Test Example 2 With respect to Example 2 and Comparative Example 4, performance evaluation of the same items as in Test Example 1 was performed. The results are shown in Table 2.

From these results, it can be seen that the polypropylene glycol (6 mol) monooleate obtained by the method of the present invention has high purity, good color and odor, and is stable against heating and aging.

Example 3 To 564 g (2 mol) of oleic acid prepared in Example 1,
Tetraethylammonium chloride 6.6 g (0.04
(1 mol) was placed in one autoclave, the atmosphere was replaced with nitrogen gas, and the mixture was heated to 90 ° C. and the pressure was adjusted to 0.
It was adjusted to 5 kg / cm ² G. Then, 88 g (2 mol) of ethylene oxide was injected under pressure at 80 to 100 ° C. under 5 kg / cm ² G for about 5 hours to react. 9 more
After continuing the reaction at 0 ° C. for 1 hour, nitrogen gas was blown in to distill off unreacted ethylene oxide. Washing with water, dehydration and filtration were carried out in the same manner as in Example 2 to obtain 620 g of ethylene glycol monooleate.

326 g of the obtained ethylene glycol monooleate
(1 mole), a three Hutu boron ether 2 g (0.14 mol), takes a mixture composed of tetrahydrofuran 216 g (3 mol) in 1 autoclave, row a nitrogen gas replacement Tsutanochi, 20~40 ℃, 5Kg / cm ² Under the conditions of G or less, 264 g (6 mol) of ethylene oxide was injected under pressure for about 10 hours to cause a reaction. Next, after neutralizing with an aqueous solution of sodium hydroxide, dehydration was performed to separate the crystal of the produced salt to obtain 750 g of polyoxyethylene (7 mol) polyoxytetramethylene glycol (3 mol) monooleate.

Test Example 3 The ester obtained in Example 3 was measured according to Test Example 1, and the values were as shown in Table 3, and the heating stability and temporal stability were very good as well as immediately after production.

Claims (1)

[Claims] 1. A total of 3 to 50 of (a) a fatty acid mixture containing oleic acid, a saturated fatty acid having 16 or more carbon atoms and a monounsaturated fatty acid higher than oleic acid contained in the fatty acid mixture. After dissolving the weight of urea and the organic solvent in an organic solvent and then cooling to separate and remove the precipitated crystals, (b) the fatty acid mixture contained in the organic solvent solution is partially saponified and then recrystallized to separate the crystals, (C) Oleic acid obtained by acid-decomposing the obtained crystal is treated with a tertiary amine or a quaternary ammonium salt as a catalyst to give 0.9 to 1.1 to 1 mol of oleic acid.
A process for producing a polyalkylene glycol monooleate, which comprises adding moles of ethylene oxide or propylene oxide, and then adding α-olefin oxide or tetrahydrofuran in the presence of a Lewis acid catalyst.