JPS6163637A - Production of lactic acid ester - Google Patents
Production of lactic acid esterInfo
- Publication number
- JPS6163637A JPS6163637A JP59182831A JP18283184A JPS6163637A JP S6163637 A JPS6163637 A JP S6163637A JP 59182831 A JP59182831 A JP 59182831A JP 18283184 A JP18283184 A JP 18283184A JP S6163637 A JPS6163637 A JP S6163637A
- Authority
- JP
- Japan
- Prior art keywords
- lactic acid
- exchange resin
- alcohol
- reaction
- ion
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
Description
【発明の詳細な説明】 ［産業上の利用分野］ 本発明は乳酸エステルの製造方法に関するものである。[Detailed description of the invention] [Industrial application field] The present invention relates to a method for producing lactic acid ester.
［従来の技術］
乳酸は良好な酸味を有し、かつ殺菌性が右することから
食品工業に広く使用されているが、近年医薬、葭薬等の
中間体としての用途が増大し無水状態の乳酸が必凹とさ
れるようになってきた。[Prior art] Lactic acid has a good sour taste and has good bactericidal properties, so it is widely used in the food industry.However, in recent years, its use as an intermediate for pharmaceuticals, medicinal products, etc. has increased, and lactic acid has been used in an anhydrous state. Lactic acid has come to be considered essential.
（こで無水状態の乳酸を１！７る方法として種々の方法
があるが、その一方法として乳酸をエステル化りる方法
がある。この方法は乳酸とアルコールとを硫酸の存在下
でｈＩ］熟りる方法である（ □ ｒｇａｎｉｃＳｙｎ
ｔｈｅｓｅｓ Ｃｏ１１ｅｃｔｉｖｅ第２巻第３６５
ページ）。(There are various methods for converting lactic acid in an anhydrous state to 1!7, and one method is to esterify lactic acid. This method involves converting lactic acid and alcohol into hI in the presence of sulfuric acid.) It is a method of ripening ( □ rganicSyn
theses Colective Volume 2 No. 365
page).
［発明が解決しようとしている問題点］この１ｊ法は、
相応の’ｊａｒ 里を上げているが、触媒として使用し
た硫酸が反応中に濃縮されて、濃硫酸にｈるトに反応後
、ｂＱ Ｍを中和し、塩として反応７１４合物中から除
去しなｉノればならないと言う問題がある。この除去操
作は、生成する硫酸塩が微細結晶となる場合が多いので
、繁雑となり、副反応も併発する。硫酸を中和しないで
そのまま７Ｌ酸エステルを蒸留精製する方法も考えられ
るが、蒸留系内でｌｌｌ１ｌＩＳ！が濃縮され、系の材
質を腐食させる。[Problem to be solved by the invention] This 1j method is
However, the sulfuric acid used as a catalyst was concentrated during the reaction, and after the reaction with concentrated sulfuric acid, bQ M was neutralized and removed as a salt from the reaction compound 714. There is a problem that you have to do it. This removal operation is complicated because the generated sulfate often becomes fine crystals, and side reactions also occur. It is also possible to directly purify the 7L acid ester by distillation without neutralizing the sulfuric acid, but lllllIS! in the distillation system! Concentrates and corrodes the material of the system.
また光学活性な乳酸を取扱う場合、その乳ｌｌ）がうＬ
ミ化する恐れがある等の問題がある。更にニスＪ゛ル化
反応系に食塩、塩化／Ｊルシウム等のハロゲン塩が共存
する場合には塩交換反応が進行し、ＩＩｉ！ｉ酸が触媒
として有効に機能しない上に、揮発性ｌ１プが光ルし、
反応系を複雑に１６゜従って、本発明の目的は上記問題
点の解潤されたマｌ、 ｆｊ！２エステルの製造５７人
の提供にある。In addition, when handling optically active lactic acid, the milk
There are problems such as the possibility of miniaturization. Furthermore, when halogen salts such as common salt and chloride/J lucium coexist in the varnish formation reaction system, a salt exchange reaction proceeds, and IIi! In addition to the i-acid not functioning effectively as a catalyst, the volatile l-p is emitted,
Therefore, the object of the present invention is to solve the above-mentioned problems. 2 ester production provided by 57 people.
［問題点を解決するための手段］
本発明の上記目的は乳酸とアルコールとをイオン交換樹
脂の存在下で５０〜・１７０℃で加熱する丁段を採用す
ることによって達成される。この手段を採用することに
よって、高純度の乳酸を鳥取＄、’（ｊｎられる。１．
１に前記イオン交換樹脂として）」型強酸性陽イオン交
換樹脂を使用すると本発明の目的は２１］率的に達成可
能できる。以下発明の開成を詳細に説明する。[Means for Solving the Problems] The above objects of the present invention are achieved by employing a method of heating lactic acid and alcohol at 50 to 170°C in the presence of an ion exchange resin. By adopting this method, high purity lactic acid can be obtained.1.
The object of the present invention can be efficiently achieved by using a strongly acidic cation exchange resin of the type 1) as the ion exchange resin. The development of the invention will be explained in detail below.
原料となる乳酸は発酵法や合成法のいずれの方法で製造
されたものでもよい。乳酸は水分を随伴してもよい。随
伴する場合は、好ましくは５〜５０重量％である。The lactic acid used as a raw material may be produced by either fermentation or synthesis. Lactic acid may be accompanied by water. When accompanying, it is preferably 5 to 50% by weight.
副原を斗であるアルコール
Ｊ−タノール、ｎ−プロパツール、イソプロパツール、
ローブタンール、イソブタノール、ＳｅＣ−ブタノール
、Ｌ−ブタノール、ローペンタノール、ｒソベンタノー
ル、ＩＩ−／’＼１リノール等の１１゛１迫ま／．：
ｉ．Ｌ分枝状の脂肪へフルー１−ルｒ：好ましく（まメ
タノール、エタノール、１１−プロパツール、イソプ１
、、１パノール、（１−ブタノール、ｌｌＩ３よびイソ
ブタノールである。Alcohol J-tanol, n-propanol, isopropanol,
11゛1 /. :
i. For L-branched fats: Preferably (methanol, ethanol, 11-propanol, isopropyl)
, 1panol, (1-butanol, llI3 and isobutanol).
触媒としてのＨ型強酸性イオン交換樹脂は公知のものが
使用可能であるが、好ましくは、スルホンＩｉｌｔ Ｉ
Ｓを右するものが使用される。As the H-type strong acidic ion exchange resin as a catalyst, known ones can be used, but sulfone Iilt I is preferably used.
Those to the right of S are used.
前記樹脂の形状はビーズ状、短繊維状、編物状、織物状
等任意の形状で使用できる。The resin can be used in any desired shape, such as beads, short fibers, knitted fabrics, and woven fabrics.
反応方法は前記樹脂の存在下で乳酸とアルコールとを加
熱反応させればよいのであるが本発明法をより効果的に
実施するには、次の二つの手法を採用する。The reaction may be carried out by heating lactic acid and alcohol in the presence of the resin, but in order to carry out the method of the present invention more effectively, the following two methods are adopted.
その一つは乳酸、アルコール類およびｎＱ記イオン交換
樹脂を同時に仕込み、ディージ・スターク法（ Ｄ ｅ
ａｎ − Ｓ ｔａｒｋ）水分離器を使用して、生成号
ろ水を共沸蒸留により分離する、いわゆる共沸１１（す
水沫であり、他は前記樹脂を充填したカラムに連続的に
乳酸とアルコールを供給し、乳酸エステルを連続的に流
出させる、いわゆる反応蒸留法である。One method is to simultaneously charge lactic acid, alcohol, and nQ ion exchange resin, and use the Digi-Stark method (D e
The product filtrate is separated by azeotropic distillation using a water separator, so-called azeotropic distillation, and the other is a column filled with the resin, in which lactic acid and alcohol are continuously separated. This is a so-called reactive distillation method in which the lactic acid ester is supplied and the lactic acid ester is continuously flowed out.
反応は５０〜１７０、好ましくは７０〜１２０”Ｃ ｃ
行なわれる。反応温度を前記範囲に任意に調節するため
には反応系に共沸溶媒を存在さぼるか、減圧系にする方
法が採用される。。The reaction is 50-170, preferably 70-120"C c
It is done. In order to arbitrarily adjust the reaction temperature within the above range, a method is employed in which an azeotropic solvent is omitted from the reaction system or a pressure reduction system is used. .
反応＋１．’１間は反応温度、イオン交換樹脂の使用量
によって異るが、実質的に反応が終了するまでで、それ
は通常２〜１５時間である。 前記原料に対ゴる前記副
原料の使用端は、等モルでよいが、反応速度を高めるた
めに、１〜１０、好ましくは、２〜４当吊とする。イオ
ン交Ｉ！樹脂の使用量は乳酸に対して、０．０１〜１当
ｍ、好ましくは、０。Reaction +1. Although the time period varies depending on the reaction temperature and the amount of ion exchange resin used, it is the time until the reaction is substantially completed, which is usually 2 to 15 hours. The amount of the auxiliary raw material used relative to the raw material may be equimolar, but in order to increase the reaction rate, it is 1 to 10, preferably 2 to 4 molar. Ion exchange I! The amount of resin to be used is 0.01 to 1 equivalent m, preferably 0, based on lactic acid.
０５〜０．３当ｍの範囲である。な４ｊ、当量はイオン
交換樹脂の苛ｖ１ソーダ交換容吊から求められる。It is in the range of 0.05 to 0.3 equim. 4j, the equivalent weight is determined from the v1 soda exchange capacity of the ion exchange resin.
反応はアルコール自体を溶媒として実施できるか、ノフ
ルー〕ールＬス外の溶媒を使用して実施してもよい。）
多者の溶媒としては省エネルギー、原料、０１原イ：１
の使用量の低減、反応時間の短縮、転化率の向上等の立
場から共沸組成を形成しかつエステルおよび溶媒と水と
の分離が可能な溶媒例えばベンゼン、トルエン、キシレ
ン、等の万香族炭化水素類やシクロヘギサン等の脂肪族
炭化水素類を使用η゛る。The reaction can be carried out using the alcohol itself as a solvent, or it may be carried out using a solvent other than the alcohol. )
As a solvent for many people, energy saving, raw materials, 01 originals: 1
Solvents that form an azeotropic composition and can separate water from esters and solvents, such as benzene, toluene, xylene, etc., are used to reduce the amount used, shorten reaction time, and improve conversion rate. Hydrocarbons and aliphatic hydrocarbons such as cyclohexane are used.
反応が終了した後、反応混合物から乳＠−Ｌニスチルを
（）ＩＪるには、陽イオン交換樹脂を反応混合ｄ々ど分
離し、次いで残った反応混合物を蒸留すればよい。更に
場合によっては反応混合物をイのまま蒸留してもよい。After the reaction is completed, the cation exchange resin can be separated from the reaction mixture and the remaining reaction mixture can then be distilled in order to extract Nistyl from the reaction mixture. Furthermore, depending on the case, the reaction mixture may be distilled as it is.
次に本発明の実施例を述べる。Next, examples of the present invention will be described.
［実施例］
実施）？＋ １
ツイーン・スターク水分離器を装着した１リットルのナ
ス型フラスコに９０％ Ｌ−乳酸１００９リ （Ｌ−乳
酸として１モル）、イソプロパツール １８０（］（３
３モル、ベンゼン ２００ｍｌＪｊよひ陽イオン交換樹
脂ｒ）Ｋ２２０（三菱化成製１１望陽イオン交換樹脂）
５０ｍｌを仕込み、分離番に水が分離してこなくなるま
で約６時間加熱）！流さμた。[Example] Implementation)? + 1 In a 1 liter eggplant-shaped flask fitted with a Tween-Stark water separator, add 90% L-lactic acid 1009 liters (1 mole as L-lactic acid), isopropanol 180 (] (3
3 mol, benzene 200ml
Pour 50ml and heat for about 6 hours until water no longer separates)! It was washed away.
反応終了（を、陽イオン交換樹脂を濾別した後常圧足留
し、イソプロパツールとベンゼンを回収した。讃縮液を
減圧蒸留し、ｂ、０．７５℃／３５ｍｍＨ（Ｊの溜升と
して１１６．２ｇのし一乳酸イソプロビルエステルをｔ
Ｆ７た。収率は８７．９％であっ／Ｓ （［α］Ｄ
９．２３”（Ｃ−４，Ｅｔ ０Ｈ））。また回収した
陽イオン交ｊ襲樹＃はそのまま再度使用できるものであ
った。After the reaction was completed, the cation exchange resin was filtered off and distilled under normal pressure to recover isopropanol and benzene. 116.2 g of monolactate isoprobyl ester as t
F7. The yield was 87.9%/S ([α]D
9.23" (C-4, Et 0H)). The recovered cation exchanger # could be used again as is.
実施例２
実施例１と同様の反応器を用いて、８５％ Ｄ−乳酸水
溶液 １０６．８ｇ （Ｄ−乳酸として１モル）、食塩
５．８ｇ （０，１モル）、イソブタノール２２２ｇ
（３七ル）、ベンゼン３００ｎ＋ｌおよび編物状陽イオ
ン交換樹＃（スルホン酸基を有する強酸性陽イオン交換
樹脂、１」型）４０ｇを仕込み、水分が分離してこなく
なるまで約８時間加熱還流した。Example 2 Using the same reactor as in Example 1, 106.8 g of 85% D-lactic acid aqueous solution (1 mol as D-lactic acid), 5.8 g of common salt (0.1 mol), and 222 g of isobutanol.
(37 L), 300 n+l of benzene, and 40 g of knitted cation exchange resin # (strongly acidic cation exchange resin with sulfonic acid group, type 1) were charged, and heated under reflux for about 8 hours until water no longer separated. .
反応終了後、ｌＧｌ物状陽イオン交換樹脂の共存下で常
圧蒸留し、イソブタノールとベンゼンを回収１、／、二
１．引続き濃縮液を減圧蒸留し、ｂ、０．９２−・・−
）、′３°Ｃ／２７ｍｍＨ（Ｊの溜升しとして塩化水先
（１２，＋右イ４ンとして検出ンをほとんど含まないＤ
−乳酸イソブチルエステル１２Ｌ８ｑを得た。After the reaction is completed, isobutanol and benzene are recovered by distillation under normal pressure in the presence of a lGl physical cation exchange resin. Subsequently, the concentrated liquid was distilled under reduced pressure to obtain b, 0.92-...-
), '3°C/27mmH (as a reservoir of J, a chloride water tip (12, + right side) containing almost no detection
-Lactic acid isobutyl ester 12L8q was obtained.
収率は８３．０％であった（［α］Ｄ ＋１２．８８＠
（ｃ ＝４．Ｅｔ ０）−１） 、ＣＩ含有ｆｆｉ
１０ １１１１ｍ以下）。The yield was 83.0% ([α]D +12.88@
(c = 4.Et 0)-1), CI-containing ffi
10 1111m or less).
実施ｐＡ３
ジムロー１・を装着した１リツトルのナス型フラスコに
ＤＬ−２−クロルプロピオン酸１０８．５リ （１七ル
）、水酸化す１ヘリウム６０ｇ （１，５［−ル）水
、５００ｍ Ｉ ＠仕込み、３ ｖＦｆｌｉｐ加熱還流
しく’、ＤＬ−乳酸を合成した。Implementation pA3 In a 1 liter eggplant-shaped flask equipped with Zimrow 1, add 108.5 liters of DL-2-chloropropionic acid (17 liters), 60 g of helium hydroxide (1,5 liters) water, 500 m I DL-lactic acid was synthesized by heating and refluxing for 3 vFlip.
反応終了１に内容物を３００ ｇになるまで濃縮した（
な、氷水中で濃硫酸２７ｇ加えて３０ ｆ＞ １７ｉ］
攪拌し！、−６
この反応混合物にイソプロパツール ２４ｏ９（４トル
）加えて攪拌した後、濾過して無機塩を除去した。濾液
に、トルエン ４００ｍ ｌおよびμＦ１′Ａ゛ン交換
樹脂５Ｋ１Ｂ（三菱化成製Ｈ型間イオン交換樹脂＞４０
ｇを仕込み、水分が分離してこなくなるまで約６時間加
熱還流させた。At the end of the reaction 1, the contents were concentrated to 300 g (
Add 27 g of concentrated sulfuric acid to 30 f > 17i in ice water.
Stir! ,-6 Isopropatol 24o9 (4 torr) was added to the reaction mixture, stirred, and then filtered to remove inorganic salts. To the filtrate, add 400 ml of toluene and μF1'A ion exchange resin 5K1B (Mitsubishi Kasei H type ion exchange resin > 40
The mixture was heated under reflux for about 6 hours until water no longer separated.
反応終了後、実施例２と同様の迅理をし、ｂ。After the reaction is completed, carry out the same procedure as in Example 2, and b.
ｐ、８９℃／６４ｍｍＨａの溜升しとしてＤ−乳酸イソ
プロビルエステル１１０．２ｇを得た。収率は８３．５
％であった（Ｃ１含有吊 ２０ ｐｐｍ以下）。110.2 g of D-lactic acid isoprobyl ester was obtained as a distillate at 89° C./64 mm Ha. Yield is 83.5
% (C1 content 20 ppm or less).
比較例
ディーン・スターク水分離器を装着した１リツトルのナ
ス型フラスコにＤＬ−乳酸１００．９（１（試薬１扱
８５．０〜９２．０％乳酸含有水溶液〉、イソブタノー
ル ２００１１１１ 、ベンゼン３００ｍ ｌおよび５
０％硫酸５１１を仕込み、分離器に水が分離してこなく
なるまで約３時間加熱還流させた。Comparative Example DL-lactic acid 100.9 (1
85.0-92.0% lactic acid containing aqueous solution>, isobutanol 2001111, benzene 300ml and 5
0% sulfuric acid 511 was charged and heated under reflux for about 3 hours until no water separated into the separator.
次いで内容液が２００ｍ１になるまで寸圧濃縮した後、
常温まで冷加した。炭酸カルシウム１０９をｈＯえて硫
酸を中和した後止成した硫酸カルシ・り１１と過剰の炭
酸カルシウムを濾別した。濾液を減圧蒸留して、ｂ、０
．８２〜ｂ
９の溜升しとして１０５．２ｇのＤ［−乳酸イソプロピ
ルエステルを得た。収率は約７２％であった。Then, after concentrating the content under pressure until the content became 200ml,
Cooled to room temperature. After neutralizing the sulfuric acid by adding 109 h of calcium carbonate, the stagnant calcium sulfate 11 and excess calcium carbonate were separated by filtration. The filtrate was distilled under reduced pressure to give b, 0
．． 105.2 g of D[-lactic acid isopropyl ester was obtained as a distillate of 82-b9. The yield was about 72%.
［発明の効果］
本発明法によれば高純度の乳酸エステルが高収率ＣＩ？
７られる。特に乳酸の中にハロゲン塩等の揮発↑１１酸
のＱが存在すると６でも高い純度の乳酸エステルが得ら
れる。[Effect of the invention] According to the method of the present invention, high purity lactic acid ester can be produced with high yield of CI?
7. In particular, if Q of a volatile ↑11 acid such as a halogen salt is present in lactic acid, a highly pure lactic acid ester can be obtained even with 6.
さらに光学活性な乳酸エステルを使用してもそれが反応
器でうＵミ化１１ることなく得られる。Furthermore, even if an optically active lactic acid ester is used, it can be obtained in a reactor without U-milization.
Claims (2)
５０〜１７０℃で加熱することを特徴とする乳酸エステ
ルの製造方法。(1) A method for producing a lactic acid ester, which comprises heating lactic acid and alcohol at 50 to 170°C in the presence of an ion exchange resin.
ある特許請求の範囲第１項記載の乳酸エステルの製造方
法。(2) The method for producing a lactic acid ester according to claim 1, wherein the ion exchange resin is an H-type strongly acidic cation exchange resin.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59182831A JPS6163637A (en) | 1984-09-03 | 1984-09-03 | Production of lactic acid ester |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59182831A JPS6163637A (en) | 1984-09-03 | 1984-09-03 | Production of lactic acid ester |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6163637A true JPS6163637A (en) | 1986-04-01 |
| JPH0577662B2 JPH0577662B2 (en) | 1993-10-27 |
Family
ID=16125227
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP59182831A Granted JPS6163637A (en) | 1984-09-03 | 1984-09-03 | Production of lactic acid ester |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6163637A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1300387A1 (en) * | 2001-10-05 | 2003-04-09 | Haltermann GmbH | Process for the preparation of hydroxy carboxylic acid esters |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1294371A (en) * | 1969-03-13 | 1972-10-25 | Basf Ag | PRODUCTION OF alpha-HYDROXYCARBOXYLIC ESTERS |
| JPS5636434A (en) * | 1979-09-01 | 1981-04-09 | Tokuyama Soda Co Ltd | Preparation of tartaric acid or epoxysuccinic acid diester |
-
1984
- 1984-09-03 JP JP59182831A patent/JPS6163637A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1294371A (en) * | 1969-03-13 | 1972-10-25 | Basf Ag | PRODUCTION OF alpha-HYDROXYCARBOXYLIC ESTERS |
| JPS5636434A (en) * | 1979-09-01 | 1981-04-09 | Tokuyama Soda Co Ltd | Preparation of tartaric acid or epoxysuccinic acid diester |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1300387A1 (en) * | 2001-10-05 | 2003-04-09 | Haltermann GmbH | Process for the preparation of hydroxy carboxylic acid esters |
| WO2003031386A1 (en) * | 2001-10-05 | 2003-04-17 | Haltermann Gmbh | Method for producing a hydroxyacid esters |
| CN1305833C (en) * | 2001-10-05 | 2007-03-21 | 海尔特曼公司 | Method for producing a hydroxyacid esters |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0577662B2 (en) | 1993-10-27 |
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