KR100383447B1 - Production of Sodium 2-Pyrrolidone-5-Carboxylate - Google Patents
Production of Sodium 2-Pyrrolidone-5-Carboxylate Download PDFInfo
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- KR100383447B1 KR100383447B1 KR10-2000-0036677A KR20000036677A KR100383447B1 KR 100383447 B1 KR100383447 B1 KR 100383447B1 KR 20000036677 A KR20000036677 A KR 20000036677A KR 100383447 B1 KR100383447 B1 KR 100383447B1
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D207/00—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom
- C07D207/02—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom
- C07D207/18—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having one double bond between ring members or between a ring member and a non-ring member
- C07D207/22—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having one double bond between ring members or between a ring member and a non-ring member with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D207/24—Oxygen or sulfur atoms
- C07D207/26—2-Pyrrolidones
- C07D207/273—2-Pyrrolidones with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to other ring carbon atoms
- C07D207/277—Carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals
- C07D207/28—2-Pyrrolidone-5- carboxylic acids; Functional derivatives thereof, e.g. esters, nitriles
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- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D1/00—Oxides or hydroxides of sodium, potassium or alkali metals in general
- C01D1/04—Hydroxides
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- C07C55/02—Dicarboxylic acids
- C07C55/12—Glutaric acid
Abstract
본 발명은 천연 보습인자의 주 성분인 2-피롤리돈-5-카르복시산 나트륨염 수용액을 제조하는 방법에 관한 것으로 글루타민산 또는 글루타민산과 글루타민산 나트륨염 혼합물 수용액 으로 된 반응계 내에 과량의 가성소다를 존재시키고 가열 온도를 PCA 의 융점 이하에서 반응시킴으로서 반응액중에 미전환된 글루타민산이나 글루타민산염이 잔류하지 않고 열분해물질이나 착색물질이 없이 순수한 수용액을 제조하는 방법이다.The present invention relates to a method for preparing an aqueous 2-pyrrolidone-5-carboxylic acid sodium salt solution, which is a main component of a natural moisturizing factor, wherein excess caustic soda is present in a reaction system consisting of an aqueous solution of glutamic acid or a mixture of glutamic acid and sodium glutamate. By reacting the temperature below the melting point of PCA, unconverted glutamic acid or glutamate does not remain in the reaction solution, and a pure aqueous solution is produced without pyrolysis or coloring matter.
Description
본 발명은 2-피롤리돈-5-카르복시산 나트륨염(이하 Na-PCA라 칭함) 수용액의제조 방법에 관한 것이다. Na-PCA는 피부의 천연 보습인자의 주성분으로 인체의 피부 속에 다량 존재하는 것으로 알려져 있다. 그 용도로는 천연 보습효과를 주기 위한 제품, 예를 들면 화장품, 저자극성 비누, 샴푸, 컨디셔너, 헤어토닉, 향수, 치약, 세제 등에 보습제로 사용되고 있고, 나아가 고약이나 좌약 등의 의약품, 살충제, 담배, 수용성 잉크 등에 습윤제로 사용되고 있으며, 화학합성의 중간제 원료로도 사용되고 있다. 피롤리돈 카르복시산(이하 PCA라 칭함)은 글루타민산에서 생산되는 물질로 글루타민산 분자내의 탈수 반응에 의해 생성되는 유기산의 일종이다. PCA는 결정 생성 pH가 1.90 부근으로 글루타민산의 등전점인 pH 3.2보다 낮으며 글루타민산이 PCA로 전환됨에 따라 반응액의 pH가 저하되므로 Na-PCA를 제조하기 위해서는 가성소다로 중화하여야 한다.The present invention relates to a method for producing an aqueous solution of 2-pyrrolidone-5-carboxylic acid sodium salt (hereinafter referred to as Na-PCA). Na-PCA is known to be present in the human body's skin as the main ingredient of the skin's natural moisturizing factor. Its use is used as a moisturizer for products that give natural moisturizing effects, such as cosmetics, hypoallergenic soaps, shampoos, conditioners, hair tonics, perfumes, toothpastes and detergents, and also medicines such as plasters and suppositories, pesticides and tobacco. It is used as a humectant in water-soluble inks, and is also used as a raw material for intermediates of chemical synthesis. Pyrrolidone carboxylic acid (hereinafter referred to as PCA) is a substance produced by glutamic acid and is a kind of organic acid produced by dehydration reaction in the glutamic acid molecule. PCA has a crystal formation pH of about 1.90, which is lower than the isoelectric point of glutamic acid, pH 3.2, and the pH of the reaction solution decreases as glutamic acid is converted to PCA. Therefore, it is required to neutralize with caustic soda to prepare Na-PCA.
종래 Na-PCA를 제조하는 방법으로는 글루타민산 및 글루타민산나트륨 혼합물의 현탁액을 200℃의 고온 및 그압력하에서 열처리하여 생성된 반응액을 가성소다로 중화하여 Na-PCA의 수용액을 제조하는 방법(일본특허공개공보 소 51-110559)이있다.Conventionally, a method for preparing Na-PCA is a method of preparing an aqueous solution of Na-PCA by neutralizing the reaction solution produced by heat-treating a mixture of glutamic acid and sodium glutamate at a high temperature of 200 ° C. and its pressure with caustic soda. Publication No. 51-110559.
그러나 이 방법은 반응액중에 2%정도의 미반응 글루타민산이 잔류하게 되고 고온 고압하에서 반응시키기 때문에 열분해산물이 생성되고 반응액이 착색되는 현상이 발생한다. 따라서 순수한 Na-PCA를 얻기 위하여는 잔류 글루타민산을 제거하는 공정을 거쳐야 되고, 탈색공정이 필요하게 되어 공정이 복잡해질 뿐만 아니라 수율이 떨어지는 걸점이 있다.However, in this method, about 2% of unreacted glutamic acid remains in the reaction solution and reacts under high temperature and high pressure, so that thermal decomposition products are generated and the reaction solution is colored. Therefore, in order to obtain pure Na-PCA, it is necessary to go through a process of removing residual glutamic acid, and a decolorizing process is required, which not only complicates the process but also lowers the yield.
Na-PCA를 제조하는 또 하나의 방법으로는 고체상태의 글루타민산 나트륨염을210～270℃로 가열하여 글루타민산의 탈수 과정에서 생성되는 물이 즉시 증발되도록하여 고체상태의 Na-PCA를 제조하는 방법(미국특허공보4,921,971)이 있다.Another method of preparing Na-PCA is to prepare a solid Na-PCA by heating the sodium glutamate in the solid state to 210 ~ 270 ℃ to immediately evaporate the water produced during the dehydration of glutamic acid ( US Patent Publication No. 4,921,971.
이 방법은 고체상태의 원료를 고온에서 단시간 가열하게 되므로 열분해 산물이 생성되어 순도를 떨어뜨릴 뿐만 아니라 산업적인 생산공정에서 다량의 고체원료를 단시간에 균일하게 가열하는 것은 현실적으로 어렵기 때문에 비효과적인 방법이다.This method is not effective because heating the solid state raw material at high temperature for a short time, not only produces the pyrolysis products, but also lowers the purity, and it is difficult to uniformly heat a large amount of solid raw material in a short time in the industrial production process. .
본 발명의 목적은 Na-PCA 수용액을 제조함에 있어서 열분해 산물이 혼입되지않고 또한 착색물질이 제조 과정에서 생성되지 않도록 함으로서 이물질 제거 공정이나 탈색 공정을 거치지 않고 반응액 그 자체를 그대로 제품으로 사용할 수 있도록 하는 방법을 제시하는 것이다.It is an object of the present invention to prepare a Na-PCA aqueous solution so that pyrolysis products are not mixed and colorants are not produced during the manufacturing process so that the reaction solution itself can be used as a product without undergoing a foreign material removal process or a decolorization process. Is to present a way.
상기목적을 달성하기 위하여 연구를 한 결과 본 발명자등은 글루타민산 또는글루타민산과 글루타민산나트륨염을 혼합한 현탁액을 과량의 가성소다 존재 하에 융점 이하의 온도에서 가열하면 글루타민산이나 그의 염이 전부 Na-PCA로 전환되고반응액 중에는 열분해산물이 생성되지 않고 착색현상도 없는 순수한 Na-PCA 수용액을 제조할 수 있다는 것을 발명하였다.In order to achieve the above object, the present inventors found that glutamic acid or its salts are all converted to Na-PCA when a suspension of glutamic acid or a mixture of glutamic acid and sodium glutamate is heated at a temperature below the melting point in the presence of excess caustic soda. It was invented that a pure Na-PCA aqueous solution without a thermal decomposition product and no coloring phenomenon can be prepared in the reaction solution.
글루타민산에서 PCA로의 가열에 의한 전환반응은 피롤리돈화 과정이 탈수 평형반응이고 그 평형계수는 PCA측으로 기울며 총 고형분당 중량 비 7～10% 정도의 글루타민산이 혼입된다. 또한 글루타민산의 물에 대한 용해도는 25℃에서 8.65g/L이며 PCA는 20g/L이다. 따라서 용해도 차이나 평형반응을 조절하여 글루타민산의 혼입을 막기는 어렵게 된다. 따라서 Na-PCA 수용액을 얻기 위해서는 평형이 된 반응액을 글루타민산이나 그 염류를 분리해내는 정제공정을 거쳐 얻은 PCA 액을 중화하여야 하므로 공정이 복잡하고 수율이 떨어지게 되므로 가능한 한 반응계 내에서 글루타민산이 전량 PCA로 전환되도록 하는 것이 가장 바람직 하다.In the conversion reaction of glutamic acid to PCA, the pyrrolidone process is a dehydration equilibrium reaction, the equilibrium coefficient is inclined toward PCA, and glutamic acid with 7-10% by weight of total solids is incorporated. In addition, the solubility of glutamic acid in water is 8.65 g / L at 25 ° C. and PCA is 20 g / L. Therefore, it is difficult to prevent the incorporation of glutamic acid by adjusting the solubility difference or the equilibrium reaction. Therefore, in order to obtain Na-PCA aqueous solution, it is necessary to neutralize the PCA solution obtained through the purification process to separate the glutamic acid or its salt from the equilibrium reaction solution, so that the process is complicated and the yield is reduced, so that the total amount of glutamic acid in the reaction system is possible. It is most desirable to allow the conversion to.
본 발명에서 과량의 가성소다를 반응계에 존재시키는데, 과량이라 함은 원료로 사용한 글루타민산이 전량 PCA로 전환되었을 때 그 반응액을 중화하는데 소요되는 양의 1～1.5배 양을 미리 반응계에 존재시켜 알칼리하에서 반응시키는 방법이다. 가성소다를 가하는 방법은 반응초기나 반응 후반에 전량을 가하여도 되고, 반응중간에 나누어 가하여도 좋으나, 반응 종료 이전에 전량을 가하여 알칼리 상태에서 최종반응이 일어나도록 함으로써 미반응 글루타민산이나 그의 염이 잔류하지 않도록 하는 것이 중요하다.In the present invention, an excess of caustic soda is present in the reaction system. When the excess glutamic acid used as a raw material is converted into the total amount of PCA, an amount of 1 to 1.5 times the amount required to neutralize the reaction solution is present in the reaction system to give alkali. The reaction is carried out under. Caustic soda may be added at the beginning of the reaction or at the end of the reaction, or may be added in the middle of the reaction.However, before the end of the reaction, the total amount of caustic soda may be added to allow the final reaction to occur in an alkaline state, thereby remaining unreacted glutamic acid or its salt. It is important not to.
또한 본 발명에서의 열처리 온도는 PCA의 융점 이하의 온도에서 실시하는 것이 중요하다. PCA의 융점은 162～163℃로 융점 이상의 고온에서 열처리할 경우 반응 시간은 단축할 수 있으나 열 분해산물이나 착색현상이 발생하게 되므로 바람직하지 않다.In addition, it is important to perform the heat processing temperature in this invention at the temperature below melting | fusing point of PCA. The melting point of PCA is 162 ～ 163 ℃, which can shorten the reaction time when heat treated at high temperature above melting point, but it is not preferable because thermal decomposition products or coloring phenomenon occur.
본 발명에서 가열처리 시간은 총 2～10시간으로, 사용하는 가성소다 양이나 반응 온도에 따라 적절히 조절 가능하다.In the present invention, the heat treatment time is 2 to 10 hours in total, and can be appropriately adjusted according to the amount of caustic soda used and the reaction temperature.
본 발명의 방법에 의하여 제조한 Na-PCA 수용액은 알칼리성이므로 중성으로조절할 필요가 있다. 중화에는 황산, 염산 등의 무기산을 사용할 수 있으나 이 경우는 Na-PCA 수용액 중에 황산염이나 염산염이 존재하게 되므로 바람직하지 않다.The Na-PCA aqueous solution prepared by the method of the present invention is alkaline and needs to be adjusted to neutral. In the neutralization, inorganic acids such as sulfuric acid and hydrochloric acid may be used, but in this case, since sulfates or hydrochlorides are present in an aqueous Na-PCA solution, it is not preferable.
본 발명에서는 제조한 Na-PCA 수용액을 중화하는 데는 산성의 PCA 수용액을사용한다. 이 산의 제조는 본 발명에서 얻은 Na-PCA 수용액을 황산 또는 염산 등의무기산으로 pH 1.9로 부근으로 조절하여 PCA 결정을 석출시키고 여과하면 순수한 결정을 얻게된다. 이 결정을 물에 현탁한 후 가열 용해하여 PCA 수용액으로 한다.In the present invention, an acidic PCA aqueous solution is used to neutralize the prepared Na-PCA aqueous solution. In the preparation of this acid, the Na-PCA aqueous solution obtained in the present invention is adjusted to pH 1.9 with an inorganic acid such as sulfuric acid or hydrochloric acid, and precipitated PCA crystals and filtered to obtain pure crystals. This crystal is suspended in water, dissolved in heat to obtain an aqueous PCA solution.
이하 실시예를 들어 본 발명의 방법을 상세히 설명한다.The method of the present invention will be described in detail with reference to the following Examples.
실시예 1Example 1
글루타민산 100g에 물 78ml를 가하여 현탁 후 삼각 플라스크에 넣어 가압솥에서 140℃로 6시간 가열한 다음 가성소다 30g (PCA중화에 소요되는 양의 1.1배)을가하고 동일 온도에서 20분간 재가열하여 반응시켰다. 반응 완료후 ninhydrin법으로 분석한 결과 글루타민산은 검출되지 않았다.78 ml of water was added to 100 g of glutamic acid, suspended, and put into a Erlenmeyer flask and heated at 140 ° C. for 6 hours in a pressure cooker. Then, 30 g of caustic soda (1.1 times the amount required for neutralization of PCA) was added and reacted by reheating at the same temperature for 20 minutes. After completion of the reaction, glutamic acid was not detected by ninhydrin analysis.
상기 반응액을 중화용 PCA수용액으로 pH 7.0으로 조절하여 순수한 Na-PCA 수용액 224g을 얻었다. 중화에는 PCA 수용액 18g이 소요되었다. 수율은 이론치의 98.9%에 달하였으며 수용액은 무색무취이고 분해산물은 전혀 함유되지 않았다.The reaction solution was adjusted to pH 7.0 with an aqueous PCA solution for neutralization to obtain 224 g of a pure Na-PCA aqueous solution. Neutralization took 18 g of aqueous PCA solution. The yield reached 98.9% of theory. The aqueous solution was colorless and odorless and contained no degradation products.
중화용 PCA 수용액 제조는 상기의 방법에 따라 만든 반응액에 30% 황산을 가하여 pH 1.9로 조절한 후 생성된 PCA 결정을 여과 분리하였다. 분리한 PCA 결정을 물에 현탁 후 70℃로 가열 용해하여 중화용 PCA 수용액으로 하였다.In the neutralization of PCA aqueous solution, 30% sulfuric acid was added to the reaction solution prepared according to the above method, adjusted to pH 1.9, and the resulting PCA crystals were separated by filtration. The separated PCA crystals were suspended in water and dissolved by heating at 70 ° C. to obtain an aqueous PCA solution for neutralization.
실시예 2Example 2
실시예 1과 동일한 방법으로 하여 가압솥에서 120℃에서 8시간 가열한 다음가성소다 41g (PCA 중화에 소요되는 양의 1.5배)을 가하고 동일 온도에서 30분간 재가열하여 반응시켰다. 이 반응액을 중화용 PCA 수용액으로 중화하여 Na-PCA 수용액 307g을 얻었다. 수율은 99.2%이었고 글루타민산이나 착색물질은 검출되지 않았다.In the same manner as in Example 1 was heated for 8 hours at 120 ℃ in a pressure cooker, 41g of caustic soda (1.5 times the amount required to neutralize the PCA) was added and reheated at the same temperature for 30 minutes to react. The reaction solution was neutralized with a neutralized PCA aqueous solution to obtain 307 g of an Na-PCA aqueous solution. The yield was 99.2% and no glutamic acid or colorant was detected.
실시예 3Example 3
실시예 1과 동일한 방법으로 하여 가압솥에서 160℃ 3시간 가열한 다음 가성소다 35g (PCA 중화에 소요되는 양의 1.3배)을 가하여 실시예 1과 동일하게 반응시켜 Na-PCA 수용액 261g을 얻었다. 수율은 99.0%이었고 불순물은 검출되지 않았다.In the same manner as in Example 1, the mixture was heated at 160 ° C. in a pressure cooker for 3 hours, and 35 g of caustic soda (1.3 times the amount of PCA neutralization) was added thereto to react in the same manner as in Example 1 to obtain 261 g of an aqueous Na-PCA solution. The yield was 99.0% and no impurities were detected.
실시예 4Example 4
글루타민산 50g과 글루타민산나트륨 50g을 물 98ml에 현탁하고 가성소다 19g(PCA 중화에 소요되는 량의 1.2배)을 가한 후 150℃에서 5시간 가열하여 반응시켰다. 반응액에 있는 과량의 가성소다를 PCA 수용액 35g으로 중화하여 Na-PCA 수용액 225g을 얻었다. 수율은 99.2%이었으며 글루타민산은 검출되지 않았다. 반응액을 HPLC (NH2컬럼사용)로 분석한 결과 Na-PCA 단일 Peak를 보였으며 글루타민산이나 다른물질은 나타나지 않았다.50 g of glutamic acid and 50 g of sodium glutamate were suspended in 98 ml of water, 19 g of caustic soda (1.2 times the amount of PCA neutralization) was added, and the mixture was heated and reacted at 150 ° C. for 5 hours. Excess caustic soda in the reaction solution was neutralized with 35 g of aqueous PCA solution to obtain 225 g of Na-PCA aqueous solution. The yield was 99.2% and no glutamic acid was detected. The reaction solution was analyzed by HPLC (using NH 2 column) and showed a single peak of Na-PCA, but no glutamic acid or other substances.
전술한 기제 내용으로부터 밝혀진 바와 같이 본 발명의 방법으로 제조한 Na-PCA 수용액은 가열에 의한 분해산물이나 착색물질이 생성되지 않기 때문에 이후의 정제공정이나 탈색공정이 필요없고 고 수율로 Na-PCA 수용액을 얻을 수 있다.As can be seen from the above description, the Na-PCA aqueous solution prepared by the method of the present invention does not generate decomposition products or coloring substances by heating, and thus does not require subsequent purification or decolorization, and thus, Na-PCA aqueous solution in high yield. Can be obtained.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JPS51110559A (en) * | 1975-03-24 | 1976-09-30 | Ajinomoto Kk | 22 piroridon 55 karubonsanarukarikinzokuensuiyoekinoseizoho |
| JPH01132559A (en) * | 1987-10-17 | 1989-05-25 | Degussa Ag | Production of alkali metal salt of 2-pyrrolidone-5-carboxylic acid |
| US5369122A (en) * | 1991-03-28 | 1994-11-29 | Amino Gmbh | Process for manufacturing a humectant |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JPS51110559A (en) * | 1975-03-24 | 1976-09-30 | Ajinomoto Kk | 22 piroridon 55 karubonsanarukarikinzokuensuiyoekinoseizoho |
| JPH01132559A (en) * | 1987-10-17 | 1989-05-25 | Degussa Ag | Production of alkali metal salt of 2-pyrrolidone-5-carboxylic acid |
| US5369122A (en) * | 1991-03-28 | 1994-11-29 | Amino Gmbh | Process for manufacturing a humectant |
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