KR100262422B1 - Method for separating and purifying high purity unsaturated fatty acid using crystallization - Google Patents

Abstract

PURPOSE: Provided is a method for separating and purifying high purity unsaturated fatty acid(molecular encapsulation technique), which minimize a contact of fatty acid with air in urea adduct, and is excellent in stability, as well as controls behavior of molecular group and optionally increase selectivity for separation and purification of high purity. CONSTITUTION: The method comprises the steps of (i) mixing methanol, urea and fatty acid of vegetable oil in ratio of 3.5-4.5:1-2:1 to obtain a mixture, (ii) heating the mixture to 65-75deg.C to form a urea adduct, (iii) cooling the urea adduct to 40-50deg.C in the rate of 0.2-0.5deg.C/minutes by portionwise injecting an fatty acid in 5-8 times, while saturated fatty acid is filtered and removed, to obtain a high purity unsaturated fatty acid in the form of urea adduct. The fatty acid of vegetable oil is a fatty acid produced by using safflower oil and olive oil containing high concentration of oleic acid or linoleic acid, as raw materials.

Description

Separation and Purification Method of High Purity Unsaturated Fatty Acid Using Crystallization Method

The present invention relates to a method for separating and purifying unsaturated fatty acids in fatty acids present in vegetable oils using the urea addition crystallization method.

The physiological action of fatty acids in these vegetable oils is generally as follows. Vegetable oils include saturated fatty acids such as palmitic acid and stearic acid and unsaturated fatty acids such as palmitooleic acid, oleic acid, linoleic acid and linolenic acid. Palmitooleic acid is used as a raw material and skin protection agent in cosmetics, and oleic acid is known as an ointment, skin absorption accelerator (pace, transdermal administration patch), triolein and synthetic phospholipids, cell culture medium. In addition, linoleic acid has an essential fatty acid source, anti-inflammatory action, cosmetic raw material (vitamin complex), and function to prevent skin keratinization. Gamma-linolenic acid is a precursor of prostaglandin series 1 and has the effect of improving skin diseases, preventing and treating arteriosclerosis and high blood pressure.Alphalinolenic acid is a precursor of EPA synthesis, lowers blood cholesterol, prevents heart disease, and prevents adult diseases. Has the effect of.

Therefore, the present invention relates to a method for separating and purifying unsaturated fatty acids, which are not only a source of energy but also very beneficial to the human body constituting biolipids in cell membranes such as vitamins and hormones, using urea addition crystallization and cooling crystallization.

Urea addition crystallization is widely known as a method for separating and purifying unsaturated fatty acids, which have been known in the related art, but it has been used only for medium purity separation because it does not control the behavior of the urea molecule group. Therefore, development of urea addition crystallization technology and other new technology has been required in high purity separation purification.

Conventional urea addition crystallization methods are known as alcoholic liquid cooling (US Patent No. 1240513; Haagsma, JAOCS, 59, 117 (1982); Ratnayake, FatSci. Tchnol. 90, 381 (1988)) for dissolving fatty acids and urea simultaneously. However, since they do not control the size of the molecular group of the urea, the urea and the urea adduct are precipitated at the same time as a crystal when cooling, the utilization of the urea is greatly reduced, there is a disadvantage that can not remove the unnecessary fatty acids. Therefore, the conventional methods have to compensate for this by slowing the cooling rate very slowly.

However, this method is difficult to mass-produce because the process time is very slow, the long time the unsaturated fatty acid stays at a high temperature, so that the acidification proceeds quickly and its oxidation stability is lowered, so it is difficult to be applied to the mass production process.

The present invention has developed a method for controlling the behavior of the urea molecule group in order to improve this disadvantage. By controlling the behavior of the urea molecule group, the present invention is able to form urea adducts completely without desired crystallization of urea even at high cooling rates, so that the present invention provides a molecular encapsulation that minimizes air contact of fatty acids present in the urea adduct. As a molecular encapsulation technology, the stability is very good and the selectivity of the separation is greatly increased by controlling the molecular group behavior for high purity separation purification.

Figure 1 is a simplified representation of the process of forming the element addition body of the present invention.

Figure 2 is a simple representation of the process diagram of the present invention.

Therefore, in the present invention, a mixture of methanol: urea: vegetable oil fatty acid in a weight ratio of 3.5 to 4.5: 1 to 2: 1 is heated to 65 to 75 ° C. to form urea adduct, and the fatty acid is formed at a final temperature of 40 to 50 ° C. Saturated fatty acids are filtered off while cooling at a cooling rate of 0.2 to 0.5 deg. C / min by 5 to 8 divided injections, to provide a method for separating and purifying high purity unsaturated fatty acids in the form of the obtained urea adduct. At this time, the vegetable oil fatty acid is characterized by safflower oil, olive oil, and jade oil, which are vegetable oils containing high concentrations of oleic acid or linoleic acid, and the layers are separated by adding 0.5-5% aqueous hydrochloric acid solution in the form of urea adduct. It is characterized by extracting and separating only highly unsaturated fatty acids which are supernatants. The unsaturated fatty acid obtained at this time is an unsaturated fatty acid of 99% or more purity selected from oleic acid, linoleic acid or linolenic acid.

Meanwhile, the present invention further provides a mixed solution obtained by mixing a linear or cyclic hydrocarbon organic solvent having 5 to 7 carbon atoms with a fatty acid at a ratio of 1 to 4: 1 at an initial temperature of 40 to 50 ° C to about 5 ° C. / Minute-0. It is to provide a method for the separation and purification of high-purity unsaturated fatty acid characterized in that the fatty acid is obtained in crystalline form by cooling at a cooling rate of 5 ℃ / min, wherein the unsaturated fatty acid obtained is characterized in that it is undecinoic acid.

Hereinafter, the present invention will be described in more detail.

In the present invention, the ratio of methanol: urea: fatty acid is 3.5 to 4.5: 1 to 2: 1 and completely dissolved at 65 to 75 ° C., followed by cooling to 40 to 50 ° C. at a high cooling rate of 0.2 ° C. to 0.5 ° C./min. By injecting 4-8 times of fatty acid, a non-equilibrium cooling state is formed. Therefore, in equilibrium cooling, the difference in crystal precipitation temperature due to the formation of the molecular group of urea and urea adduct is about 4 ~ 5 ℃, which makes it impossible to avoid urea crystallization. This results in an almost full amount of urea adduct at high cooling rates.

1 shows a process of forming the element addition body.

Therefore, by applying such a split injection method, it was possible to form only the desired fatty acid as urea adduct by reducing the amount of urea in the ratio of conventional urea and fatty acid and separating the temperature section (70 ℃ → 50 ℃, 40 ℃) to be cooled. .

In still another embodiment of the present invention, the desired fatty acids are cooled by cooling the organic solvent and the fatty acid mixture solution (1-4: 1) at a cooling rate of 0.2 to 0.5 ° C / min from 40 to 50 ° C to 5 ° C without using the urea. Obtained as a crystal.

Therefore, the present invention can induce mass production and oxidation stability due to the shortening of the process time. 2 is a view showing a process diagram of the present invention.

From this process diagram, the first embodiment can obtain a product having a purity of 99% or more by using primary and secondary urea addition crystallization using safflower oil. In addition, the second embodiment using olive oil can obtain more than 99% purity throughout the whole process, and undecynoic acid can obtain more than 99% purity using only cooling crystallization without using urea. have.

The present invention is explained in more detail in the following Reference Examples and Examples.

Reference Example 1

[Conversion of Neutral Lipids to Fatty Acids]

Fatty acid conversion of neutral lipid was performed according to AOAC method. First, NaOH (480g) and Na ₂ EDTA (5g) are dissolved in a mixture of water (1. 6L) and ethanol (1.6L) at 60 ° C, and neutral lipid (1kg) is added and saponified for 30 minutes. After hexane (7L) and water (0.8L) was injected and allowed to stand after mixing and stirring for 1 hour. After removing the non-saponifying material of the upper layer, concentrated hydrochloric acid is injected into the lower layer solution, and titrated to pH 1 to recover the fatty acid layer of the upper layer, and hexane is removed by a rotary vacuum evaporator.

Reference Example 2

[Analysis of Fatty Acid Composition]

The fatty acid methyl ester was converted by the AOAC method to analyze the composition of the fatty acid. The gas chromatographic analyzer used is Hewlett Packard's HP5890 series II, the detector is Hewlett Packard's FID, and the column used is Hewlett Packard's supelcowax, and the analysis temperature is 175 ℃ → 24O ℃ (2.5 ℃ / min ), The injector temperature is 250 ° C and the detector temperature is 260 ° C.

Example 1

Safflower oil fatty acid (1kg) (fatty acid composition: palmitic acid (8%), stearic acid (1.7%), oleic acid (15%) converted to safflower oil fatty acid (1kg) by adding 1.5 kg of urea to 4 L of methanol and completely dissolving at 70 ° C. ), Linoleic acid (75%) and gamma linolenic acid (0.3%) are injected in 5-8 times, cooled to 40 ℃ and filtered. Methanol was evaporated from the filtrate by a vacuum rotary evaporator, and 1L of water and a small amount of hydrochloric acid were added to the remaining solid and stirred. Then, the fatty acid layer of the upper layer is recovered. Then, 1.5 kg of urea was added again to 4 L of methanol, and completely dissolved at 70 ° C., and the recovered fatty acid was divided into 5 to 8 times and cooled to 10 ° C.

The liquid is filtered again to recover solid particles. Water (2 L) and hexane (2 L) are added to the solid particles, and a small amount of hydrochloric acid is added to decompose the supernatant. After washing two or three times with water, hexane is removed.

The composition and recovery rate of the obtained fatty acid were carried out by the method of Reference Example 2 and are shown in Table 1.

Example 7

Olive oil fatty acid (1kg) (fatty acid composition: palmitic acid (12%), palmitooleic acid (2%), stearic acid) was added to 5 L of methanol and 5 kg of urea and completely dissolved at 70 ° C. (4%), oleic acid (70%), linoleic acid (12%)), divided into several injections, cooled to 50 ℃ and filtered. Methanol was evaporated from the filtrate by vacuum rotary evaporator, and 2L of water and a small amount of hydrochloric acid were added to the remaining solid and stirred. Then, the fatty acid layer of the upper layer is recovered. 1 kg of urea was added again to 4 L of methanol, completely dissolved at 70 ° C., and the recovered fatty acid was divided into 5 to 8 times and cooled to 47 ° C. After this solution is filtered again to recover solid particles, 2 L of methanol is added to the solid particles, and completely dissolved at 70 ° C., and then cooled to 40 ° C. The liquid is filtered again to recover solid particles. Water (2 L) and hexane (2 L) are added to the solid particles, and a small amount of hydrochloric acid is added to decompose the supernatant. After washing with water two or three times, hexane is removed. The amount of fatty acid obtained at this time can be obtained about 350g. Then, 700 ml of hexane was added again and completely dissolved, and then cooled to -5 ° C. The resulting crystals are then filtered to remove hexane.

The composition and recovery rate of the obtained fatty acid were carried out by the method of Reference Example 2 and are shown in Table 1.

Example 3

1 kg of 10-undecinoic acid mixture (fatty acid composition: undecinoic acid (82%), bromine derivative (15%), undecylenic acid (3%)) was dissolved in 2 L of hexane at 40 ° C, and then slowly cooled to room temperature. Thereafter, the obtained crystals were filtered, and the crystals were added to 1 L of hexane again, dissolved at 40 ° C., and then slowly cooled to room temperature. The crystals obtained are then filtered and the hexane adsorbed to the crystals is removed. The composition and recovery rate of the obtained fatty acid were carried out by the method of Reference Example 2 and are shown in Table 1.

Example 4

1 kg of 10-undecinoic acid mixture (fatty acid composition: undecinoic acid (82%), bromine derivative (15%), undecylenic acid (3%)) was dissolved in 2 L of heptane at 50 ° C, and then slowly cooled to room temperature. Thereafter, the obtained crystals were filtered, and the crystals were added to 1 L of hexane again, dissolved at 50 ° C., and slowly cooled to room temperature. The crystals obtained are then filtered and the heptanes adsorbed on the crystals are removed. The composition and recovery rate of the obtained fatty acid were carried out by the method of Reference Example 2 and are shown in Table 1.

Example 5

1 kg of 10-undecinoic acid mixture (fatty acid composition: undecinoic acid (82%), bromine derivative (15%), undecylenic acid (3%)) in 2L of cyclohexane was dissolved slowly at 5 ° C. Cool. Thereafter, the obtained crystals were filtered, and the crystals were added to 1 L of hexane again, dissolved at 30 ° C., and slowly cooled to 5 ° C. The crystals obtained are then filtered and the cyclohexane adsorbed on the crystals is removed. The composition and recovery rate of the obtained fatty acid were carried out by the method of Reference Example 2 and are shown in Table 1.

The effect of the present invention is to develop a method of controlling the behavior of the urea molecule group, and by controlling the behavior of the urea molecule group, it is possible to form urea adducts perfectly with desired fatty acids without precipitation of urea even at high cooling rates. The present invention is a molecular encapsulation technology that minimizes air contact of fatty acids in urea adducts, and has excellent stability and greatly increases the selectivity of separation by arbitrarily controlling molecular group behavior for high purity separation purification. .

Claims (4)

Methanol: Urea: vegetable oil fatty acid 3.5 to 4.5: 1 to 2: 1 The mixture of the mixture was heated to 65 to 75 ℃ to form a urea adduct, the fatty acid is 5 to 8 times at a final temperature of 40-50 ℃ 0.2 ~ 0 cooling rate by divided injection A method for the separation and purification of high purity unsaturated fatty acid in the form of urea adduct obtained by filtering off saturated fatty acid while cooling to 5 ° C / min. 2. The method of claim 1, wherein the vegetable oil fatty acid is a fatty acid prepared from safflower oil and olive oil, which are vegetable oils containing high concentrations of oleic acid or linoleic acid. The method for separating and purifying highly purified unsaturated fatty acids according to claim 1, wherein the highly purified polyunsaturated fatty acid in the form of urea adduct is separated by adding 0.5-5% aqueous hydrochloric acid solution, followed by extracting and separating only the superunsaturated fatty acid which is a supernatant. . The method of claim 1, wherein the obtained unsaturated fatty acid is at least one purity 99% unsaturated fatty acid selected from oleic acid, linoleic acid or linolenic acid.