JPH02268159A - Method for separating chloropyridines - Google Patents
Method for separating chloropyridinesInfo
- Publication number
- JPH02268159A JPH02268159A JP8868689A JP8868689A JPH02268159A JP H02268159 A JPH02268159 A JP H02268159A JP 8868689 A JP8868689 A JP 8868689A JP 8868689 A JP8868689 A JP 8868689A JP H02268159 A JPH02268159 A JP H02268159A
- Authority
- JP
- Japan
- Prior art keywords
- pyridine
- chloropyridine
- dichloropyridine
- organic solvent
- reaction mixture
- 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
- 238000000034 method Methods 0.000 title claims description 16
- 150000005753 chloropyridines Chemical class 0.000 title 1
- JUJWROOIHBZHMG-UHFFFAOYSA-N Pyridine Chemical compound C1=CC=NC=C1 JUJWROOIHBZHMG-UHFFFAOYSA-N 0.000 claims abstract description 84
- OKDGRDCXVWSXDC-UHFFFAOYSA-N 2-chloropyridine Chemical compound ClC1=CC=CC=N1 OKDGRDCXVWSXDC-UHFFFAOYSA-N 0.000 claims abstract description 45
- UMJSCPRVCHMLSP-UHFFFAOYSA-N pyridine Natural products COC1=CC=CN=C1 UMJSCPRVCHMLSP-UHFFFAOYSA-N 0.000 claims abstract description 42
- FILKGCRCWDMBKA-UHFFFAOYSA-N 2,6-dichloropyridine Chemical compound ClC1=CC=CC(Cl)=N1 FILKGCRCWDMBKA-UHFFFAOYSA-N 0.000 claims abstract description 26
- 239000011541 reaction mixture Substances 0.000 claims abstract description 18
- 239000003960 organic solvent Substances 0.000 claims abstract description 16
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 14
- 239000003085 diluting agent Substances 0.000 claims abstract description 13
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 claims abstract description 10
- 239000000460 chlorine Substances 0.000 claims abstract description 10
- 229910052801 chlorine Inorganic materials 0.000 claims abstract description 10
- 238000005660 chlorination reaction Methods 0.000 claims abstract description 9
- 238000000605 extraction Methods 0.000 claims abstract description 7
- 239000008346 aqueous phase Substances 0.000 claims abstract description 6
- MVPPADPHJFYWMZ-UHFFFAOYSA-N chlorobenzene Chemical compound ClC1=CC=CC=C1 MVPPADPHJFYWMZ-UHFFFAOYSA-N 0.000 claims description 20
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 claims description 9
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 claims description 6
- RELMFMZEBKVZJC-UHFFFAOYSA-N 1,2,3-trichlorobenzene Chemical compound ClC1=CC=CC(Cl)=C1Cl RELMFMZEBKVZJC-UHFFFAOYSA-N 0.000 claims description 3
- OCJBOOLMMGQPQU-UHFFFAOYSA-N 1,4-dichlorobenzene Chemical compound ClC1=CC=C(Cl)C=C1 OCJBOOLMMGQPQU-UHFFFAOYSA-N 0.000 claims description 3
- 229940117389 dichlorobenzene Drugs 0.000 claims description 3
- MAKFMOSBBNKPMS-UHFFFAOYSA-N 2,3-dichloropyridine Chemical compound ClC1=CC=CN=C1Cl MAKFMOSBBNKPMS-UHFFFAOYSA-N 0.000 claims description 2
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 claims description 2
- 239000008096 xylene Substances 0.000 claims description 2
- 150000004945 aromatic hydrocarbons Chemical group 0.000 claims 2
- 229910052500 inorganic mineral Inorganic materials 0.000 abstract description 13
- 239000011707 mineral Substances 0.000 abstract description 13
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 abstract description 12
- VZGDMQKNWNREIO-UHFFFAOYSA-N tetrachloromethane Chemical compound ClC(Cl)(Cl)Cl VZGDMQKNWNREIO-UHFFFAOYSA-N 0.000 abstract description 12
- 239000002253 acid Substances 0.000 abstract description 9
- YMWUJEATGCHHMB-UHFFFAOYSA-N Dichloromethane Chemical compound ClCCl YMWUJEATGCHHMB-UHFFFAOYSA-N 0.000 abstract description 6
- KWYUFKZDYYNOTN-UHFFFAOYSA-M potassium hydroxide Substances [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 abstract description 4
- 239000003905 agrochemical Substances 0.000 abstract description 2
- 239000003814 drug Substances 0.000 abstract description 2
- 230000001105 regulatory effect Effects 0.000 abstract 3
- 150000001875 compounds Chemical class 0.000 abstract 1
- 229940079593 drug Drugs 0.000 abstract 1
- 238000000926 separation method Methods 0.000 abstract 1
- 235000010755 mineral Nutrition 0.000 description 12
- 150000003839 salts Chemical class 0.000 description 10
- 239000000243 solution Substances 0.000 description 9
- 238000006243 chemical reaction Methods 0.000 description 7
- 238000004821 distillation Methods 0.000 description 5
- XSTXAVWGXDQKEL-UHFFFAOYSA-N Trichloroethylene Chemical group ClC=C(Cl)Cl XSTXAVWGXDQKEL-UHFFFAOYSA-N 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- 235000011121 sodium hydroxide Nutrition 0.000 description 3
- 239000002904 solvent Substances 0.000 description 3
- SLGOCMATMKJJCE-UHFFFAOYSA-N 1,1,1,2-tetrachloro-2,2-difluoroethane Chemical compound FC(F)(Cl)C(Cl)(Cl)Cl SLGOCMATMKJJCE-UHFFFAOYSA-N 0.000 description 2
- FNRMMDCDHWCQTH-UHFFFAOYSA-N 2-chloropyridine;3-chloropyridine;4-chloropyridine Chemical compound ClC1=CC=NC=C1.ClC1=CC=CN=C1.ClC1=CC=CC=N1 FNRMMDCDHWCQTH-UHFFFAOYSA-N 0.000 description 2
- HEDRZPFGACZZDS-UHFFFAOYSA-N Chloroform Chemical compound ClC(Cl)Cl HEDRZPFGACZZDS-UHFFFAOYSA-N 0.000 description 2
- CYTYCFOTNPOANT-UHFFFAOYSA-N Perchloroethylene Chemical group ClC(Cl)=C(Cl)Cl CYTYCFOTNPOANT-UHFFFAOYSA-N 0.000 description 2
- 239000003513 alkali Substances 0.000 description 2
- 239000006227 byproduct Substances 0.000 description 2
- 229910052736 halogen Inorganic materials 0.000 description 2
- 150000002367 halogens Chemical class 0.000 description 2
- 229930195733 hydrocarbon Natural products 0.000 description 2
- 150000002430 hydrocarbons Chemical class 0.000 description 2
- 239000011259 mixed solution Substances 0.000 description 2
- 239000012074 organic phase Substances 0.000 description 2
- 239000012071 phase Substances 0.000 description 2
- OENLEHTYJXMVBG-UHFFFAOYSA-N pyridine;hydrate Chemical compound [OH-].C1=CC=[NH+]C=C1 OENLEHTYJXMVBG-UHFFFAOYSA-N 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 229950011008 tetrachloroethylene Drugs 0.000 description 2
- 239000006200 vaporizer Substances 0.000 description 2
- 238000003809 water extraction Methods 0.000 description 2
- SCYULBFZEHDVBN-UHFFFAOYSA-N 1,1-Dichloroethane Chemical compound CC(Cl)Cl SCYULBFZEHDVBN-UHFFFAOYSA-N 0.000 description 1
- QCQCHGYLTSGIGX-GHXANHINSA-N 4-[[(3ar,5ar,5br,7ar,9s,11ar,11br,13as)-5a,5b,8,8,11a-pentamethyl-3a-[(5-methylpyridine-3-carbonyl)amino]-2-oxo-1-propan-2-yl-4,5,6,7,7a,9,10,11,11b,12,13,13a-dodecahydro-3h-cyclopenta[a]chrysen-9-yl]oxy]-2,2-dimethyl-4-oxobutanoic acid Chemical compound N([C@@]12CC[C@@]3(C)[C@]4(C)CC[C@H]5C(C)(C)[C@@H](OC(=O)CC(C)(C)C(O)=O)CC[C@]5(C)[C@H]4CC[C@@H]3C1=C(C(C2)=O)C(C)C)C(=O)C1=CN=CC(C)=C1 QCQCHGYLTSGIGX-GHXANHINSA-N 0.000 description 1
- XVMSFILGAMDHEY-UHFFFAOYSA-N 6-(4-aminophenyl)sulfonylpyridin-3-amine Chemical compound C1=CC(N)=CC=C1S(=O)(=O)C1=CC=C(N)C=N1 XVMSFILGAMDHEY-UHFFFAOYSA-N 0.000 description 1
- 206010007269 Carcinogenicity Diseases 0.000 description 1
- 150000008044 alkali metal hydroxides Chemical class 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 230000007670 carcinogenicity Effects 0.000 description 1
- 231100000260 carcinogenicity Toxicity 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- -1 etc. Chemical compound 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 239000000284 extract Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 150000008282 halocarbons Chemical class 0.000 description 1
- VHHHONWQHHHLTI-UHFFFAOYSA-N hexachloroethane Chemical compound ClC(Cl)(Cl)C(Cl)(Cl)Cl VHHHONWQHHHLTI-UHFFFAOYSA-N 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 239000000543 intermediate Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- BNIXVQGCZULYKV-UHFFFAOYSA-N pentachloroethane Chemical compound ClC(Cl)C(Cl)(Cl)Cl BNIXVQGCZULYKV-UHFFFAOYSA-N 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000001256 steam distillation Methods 0.000 description 1
- UBOXGVDOUJQMTN-UHFFFAOYSA-N trichloroethylene Natural products ClCC(Cl)Cl UBOXGVDOUJQMTN-UHFFFAOYSA-N 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Landscapes
- Pyridine Compounds (AREA)
- Extraction Or Liquid Replacement (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は、ピリジンの光塩素化に際し、水を希釈剤とし
て用い、得られた２−クロロピリジン。Detailed Description of the Invention (Industrial Application Field) The present invention provides 2-chloropyridine obtained by using water as a diluent during photochlorination of pyridine.
２．６−ジクロロピリジンおよび未反応のピリジンを含
む塩素化反応混合液から収率よ＜２，６−ジクロロピリ
ジン、２−クロロピリジンおよびピリジンを分離する方
法に関する。The present invention relates to a method for separating 2,6-dichloropyridine, 2-chloropyridine, and pyridine from a chlorination reaction mixture containing 2,6-dichloropyridine and unreacted pyridine with a lower yield.
２−クロロピリジンおよび２，６−ジクロロピリジンは
、医薬、農薬の中間体として非常に有用である。2-chloropyridine and 2,6-dichloropyridine are very useful as intermediates for pharmaceuticals and agricultural chemicals.
（従来の技術）
（発明が解決しようとする問題点）
２−クロロピリジンおよび２，６−ジクロロピリジンの
製造方法としては、ピリジンを紫外線照射下に塩素化し
て２−クロロピリジンを得る方法（特公昭５２−３９３
６ 、Ｕ Ｓ Ｐ ３２９７５５６号等）２−クロロピ
リジンを紫外線照射下に塩素化して、２．６−ジクロロ
ピリジンを得る方法（特公昭５６−４７４４）等が良く
知られている。(Prior art) (Problems to be solved by the invention) As a method for producing 2-chloropyridine and 2,6-dichloropyridine, there is a method for obtaining 2-chloropyridine by chlorinating pyridine under ultraviolet irradiation (particularly Kosho 52-393
A well-known method is to obtain 2,6-dichloropyridine by chlorinating 2-chloropyridine under ultraviolet irradiation (Japanese Patent Publication No. 56-4744).
上記光塩素化反応においては、タールの生成防止、原料
の燃焼あるいは爆発を防ぐため、四塩化炭素、トリクロ
ロエチレン、テトラクロロエチレンおよびテトラクロロ
ジフルオロエタン等を反応の希釈剤として用いることが
一般的に行われている。中でも四塩化炭素が好適に用い
られているが、この場合、四塩化炭素よりの生成物と思
われるヘキサクロロエタンが副生ずる。また、トリクロ
ロエチレンを希釈剤として用いた場合には、ペンタクロ
ロエタンが副生ずる。これらの高塩素化物を通常の蒸留
によって分離精製することは困難で、製品中に不純物と
して混入したり、蒸留塔の閉塞等好ましからぬ現象を引
き起こす。（特公昭６０−２０３８５ ＞同公報には、
反応液中に存在する２−クロロピリジンを鉱酸塩となし
、これを水抽出によって分離し、アルカリ中和後蒸留す
る２−クロロピリジンの精製法が開示されているが、高
純度の２−クロロピリジンを収率よ（回収するには満足
すべき方法とはいえない。In the above photochlorination reaction, carbon tetrachloride, trichlorethylene, tetrachlorethylene, tetrachlorodifluoroethane, etc. are generally used as reaction diluents in order to prevent the formation of tar and the combustion or explosion of raw materials. . Among these, carbon tetrachloride is preferably used, but in this case, hexachloroethane, which is thought to be a product from carbon tetrachloride, is produced as a by-product. Furthermore, when trichlorethylene is used as a diluent, pentachloroethane is produced as a by-product. It is difficult to separate and purify these highly chlorinated products by ordinary distillation, and they may be mixed into products as impurities or cause undesirable phenomena such as clogging of distillation columns. (Special Publication No. 60-20385 > The same bulletin states:
A method for purifying 2-chloropyridine has been disclosed in which 2-chloropyridine present in the reaction solution is converted into a mineral salt, separated by water extraction, neutralized with alkali, and then distilled. The yield of chloropyridine is not satisfactory.
さらには、上記の希釈剤として用いられる含ハロゲン炭
化水素は、近年発ガン性の問題等、安全衛生上その使用
が困難になりつつある。Furthermore, the use of halogen-containing hydrocarbons used as the diluent has recently become difficult due to safety and health concerns such as carcinogenicity.
（問題点を解決するための手段）
本発明者らは、これらの状況に鑑みて、２−クロロピリ
ジンおよび２，６−ジクロロピリジンの製造に際し、希
釈剤としてハロゲン化炭化水素を用いない方法について
鋭意検ｎを行った。(Means for Solving the Problems) In view of these circumstances, the present inventors have developed a method that does not use halogenated hydrocarbons as a diluent when producing 2-chloropyridine and 2,6-dichloropyridine. A thorough inspection was conducted.
その結果、ピリジンを塩素化して２−クロロピリジンお
よび２．６−ジクロロピリジンを製造するに際し、水を
希釈剤として用いた場合に好結果が得られ、本発明の端
緒を得た。As a result, good results were obtained when water was used as a diluent in producing 2-chloropyridine and 2,6-dichloropyridine by chlorinating pyridine, leading to the invention.
本発明は、塩素化に際し、水を希釈剤としてピリジンと
塩素とを光反応させ、得られた２−クロロピリジン、２
，６−ジクロロピリジンおよび未反応のピリジンを含む
塩素化反応混合液から収率よ＜、２．６−ジクロロピリ
ジン、２−クロロピリジンおよびピリジンを逐次回収す
る方法を提供するものである。In the present invention, 2-chloropyridine and 2-chloropyridine obtained by photoreacting pyridine and chlorine using water as a diluent during chlorination,
The present invention provides a method for successively recovering 2,6-dichloropyridine, 2-chloropyridine, and pyridine in high yield from a chlorination reaction mixture containing , 6-dichloropyridine, and unreacted pyridine.
また、本発明は、２−クロロピリジンと塩素とを光反応
させて得られる２、６−ジクロロピリジンおよび２−ク
ロロピリジンよりなる塩素化反応混合液から２，６−ジ
クロロピリジンおよび２−クロロピリジンを回収する場
合にも実施可能である。Further, the present invention provides 2,6-dichloropyridine and 2-chloropyridine from a chlorination reaction mixture consisting of 2,6-dichloropyridine and 2-chloropyridine obtained by photoreacting 2-chloropyridine and chlorine. It can also be carried out when collecting.
前述の特公昭６０−２０３８５号公報では、反応混合溶
液に鉱酸を添加することにより２−クロロピリジンを鉱
酸塩となし、これを水抽出によって分離し、アルカリ中
和後蒸留することにより２−クロロピリジンを匣収して
いる。In the above-mentioned Japanese Patent Publication No. 60-20385, 2-chloropyridine is converted into a mineral acid salt by adding a mineral acid to the reaction mixture solution, separated by water extraction, and distilled after neutralization with alkali to obtain 2-chloropyridine. -Contains chloropyridine.
しかし、この方法では、反応混合液中に多量のピリジン
が含有される場合、以下のことが知見として得られた。However, in this method, the following findings were obtained when a large amount of pyridine was contained in the reaction mixture.
（１）反応混合液中に鉱酸を添加後、水抽出するとピリ
ジンと２−クロロピリジンの双方が抽出されてしまう。(1) If a mineral acid is added to the reaction mixture and then extracted with water, both pyridine and 2-chloropyridine will be extracted.
（２） ピリジンと２−クロロピリジンを含む混合液
から両者の蒸留による分離は難しく、そのため高純度の
ピリジンおよび２−クロロピリジンの回収率が低下して
しまう。(2) It is difficult to separate pyridine and 2-chloropyridine from a mixed solution by distillation, resulting in a decrease in the recovery rate of high-purity pyridine and 2-chloropyridine.
本発明者らは、前記したピリジンと２−クロロピリジン
を含む混合液からピリジンと２−クロロピリジンを分離
する方法について更に検討の結果、両者の鉱酸塩にはそ
れぞれ、もはや鉱酸塩を形成し得ない特定のｐＨ範囲が
存在することを見出した。即ち前記した鉱酸添加後のピ
リジン、２−クロロピリジン両鉱酸塩を含む混合液を、
２−クロロピリジンが、もはや塩を形成し得す、水不溶
性となるｐＨ範囲まで中和し、遊離する２−クロロピリ
ジンを有機溶媒により抽出分離する。次いでピリジンが
塩を形成し得ないｐＨ範囲に保って、同様にピリジンを
抽出分離する。かくすることにより、両者を反応混合液
から別々に分離回収することが可能となった。As a result of further study on the method of separating pyridine and 2-chloropyridine from the above-mentioned mixed solution containing pyridine and 2-chloropyridine, the present inventors found that the mineral salts of the two no longer form mineral salts. It has been found that there are certain pH ranges in which it is not possible. That is, the mixture containing both pyridine and 2-chloropyridine mineral acid salts after addition of the mineral acid described above,
The 2-chloropyridine is neutralized to a pH range in which it is no longer soluble in water and can no longer form salts, and the liberated 2-chloropyridine is extracted and separated with an organic solvent. Next, pyridine is similarly extracted and separated while maintaining the pH within a range in which pyridine cannot form a salt. This made it possible to separate and recover both from the reaction mixture.
さらに２，６−ジクロロピリジン、２−クロロピリジン
、ピリジンの３成分を含む反応混合液からも、予め、鉱
酸塩を形成しない２，６−ジクロロピリジンのみを溶媒
により抽出分離した後、上記方法を用いれば、前記３成
分が別々に分離回収できることを見出し、本発明に到達
した。Further, from the reaction mixture containing the three components of 2,6-dichloropyridine, 2-chloropyridine, and pyridine, only 2,6-dichloropyridine that does not form a mineral acid salt is extracted and separated using a solvent, and then the above-mentioned method is used. It has been discovered that the three components can be separated and recovered separately by using this method, and the present invention has been achieved.
以下に本発明の実施態様を説明する。Embodiments of the present invention will be described below.
ピリジンと、希釈剤として用いた水および塩素よりなる
混合気を気相にて光反応させると一部固形物を含む、２
−クロロピリジン、２．６−ジクロロピリジンおよび未
反応ピリジンからなる塩素化反応混合液が得られる。When a mixture of pyridine, water used as a diluent, and chlorine is photoreacted in the gas phase, some solids are included.
A chlorination reaction mixture consisting of -chloropyridine, 2,6-dichloropyridine and unreacted pyridine is obtained.
該反応混合液に、鉱酸を添加してｐＨを１以下とすると
、含有される成分のうち、ピリジンおよび２−クロロピ
リジンは鉱酸塩を形成し、水溶性となっている。それに
対し、２，６−ジクロロピリジンは鉱酸塩を形成せず、
水不溶性となり析出してくる。反応混合液を有機溶媒で
抽出すると、先ず２．６−ジクロロピリジンのみが有機
溶媒相に抽出される。When a mineral acid is added to the reaction mixture to adjust the pH to 1 or less, pyridine and 2-chloropyridine among the contained components form mineral acid salts and are water-soluble. In contrast, 2,6-dichloropyridine does not form mineral salts;
It becomes water insoluble and precipitates out. When the reaction mixture is extracted with an organic solvent, first, only 2,6-dichloropyridine is extracted into the organic solvent phase.
次いで、２，６−ジクロロピリジン抽出後の水相を水酸
化ナトリウム、水酸化カリウム等アルカリ金属の水酸化
物によりｐ Ｈ２〜５に調整すると、塩酸塩を形成し、
溶解していたピリジンと２−クロロピリジンのうち２−
クロロピリジンは、もはや塩酸塩を形成し得ず、水不溶
性となり遊離する。Next, when the aqueous phase after 2,6-dichloropyridine extraction is adjusted to pH 2 to 5 with an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide, a hydrochloride is formed.
Of the dissolved pyridine and 2-chloropyridine, 2-
Chloropyridine can no longer form the hydrochloride salt and becomes water-insoluble and liberated.
これを有機溶媒で抽出すると２−クロロピリジンのみが
有機相に抽出されることとなる。When this is extracted with an organic solvent, only 2-chloropyridine will be extracted into the organic phase.
２−クロロピリジン抽出後の水相を更にｐＨ８〜１３と
すると、上述と同様にして有機溶媒でピリジンが有機相
に抽出される。When the aqueous phase after the 2-chloropyridine extraction is further adjusted to pH 8 to 13, pyridine is extracted into the organic phase with an organic solvent in the same manner as described above.
かくして塩素化反応混合液中のピリジン、２−クロロピ
リジン、２，６−ジクロロピリジンは、各々の有機溶媒
溶液として分離することができる。In this way, pyridine, 2-chloropyridine, and 2,6-dichloropyridine in the chlorination reaction mixture can be separated as respective organic solvent solutions.
有機溶媒溶液からピリジン、２−クロロピリジン、２，
６−ジクロロピリジンの回収は、蒸留により容易に行う
ことができる。また蒸留により抽出溶剤を留去した後、
水蒸気蒸留することによっても容易に回収可能である。Pyridine, 2-chloropyridine, 2, from organic solvent solution
6-dichloropyridine can be easily recovered by distillation. In addition, after removing the extraction solvent by distillation,
It can also be easily recovered by steam distillation.
上記した抽出に使用可能な有機溶媒としては、ピリジン
、２−゛クロロピリジンおよび２．６−ジクロロピリジ
ンは溶解するが、水には不溶な溶媒であれば何れも使用
できる。その−例を示すと、四塩化炭素、ジクロロメタ
ン、クロロホルム、ジクロロエタン、トリクロロエチレ
ン、ベンゼン、トルエン、キシレン、クロロベンゼン、
ジクロロベンゼン、トリクロロベンゼン等があげられる
が、前記した安全衛生上の理由によりトルエン、クロロ
ベンゼン、ジクロロベンゼン、トリクロロベンゼンなど
が好ましく用いられる。As organic solvents that can be used for the above extraction, pyridine, 2-chloropyridine and 2,6-dichloropyridine are soluble, but any solvent that is insoluble in water can be used. Examples include carbon tetrachloride, dichloromethane, chloroform, dichloroethane, trichloroethylene, benzene, toluene, xylene, chlorobenzene,
Examples include dichlorobenzene, trichlorobenzene, etc., and toluene, chlorobenzene, dichlorobenzene, trichlorobenzene, etc. are preferably used for the reasons of safety and health mentioned above.
以下に本発明を実施例により詳細に説明する。The present invention will be explained in detail below using examples.
（実施例）
塩素吹込管、ピリジン−水混合物気化器、温度計などを
備付けた容積１１の円筒形二重管式ガラス製反応器の中
央部に光源冷却管を置き、反応器のほぼ中心に光源ラン
プを固定した。別に反応器の直ぐ下部に冷却器を取り付
けた容積１１の四・っロフラスコを受器として置き、未
凝縮ガスはこの冷却器を通してアルカリ水溶液に吸収さ
せるようにした。(Example) A light source cooling tube was placed in the center of a cylindrical double-tube glass reactor with a capacity of 11 equipped with a chlorine blowing tube, a pyridine-water mixture vaporizer, a thermometer, etc. Fixed the light source lamp. Separately, an 11-volume four-neck flask equipped with a condenser was placed immediately below the reactor as a receiver, and uncondensed gas was absorbed into the alkaline aqueous solution through the condenser.
先ず反応器の二重管部に油を循環させ、別に用意しであ
る油浴によって反応器内の温度を１３０°Ｃに昇温させ
た。First, oil was circulated through the double tube section of the reactor, and the temperature inside the reactor was raised to 130°C using a separately prepared oil bath.
次いでピリジン−水混合物（モル比１：１０）を気化器
を経由して反応器に導入した後、光源ランプを点灯した
。続いて塩素を通気して反応させると器内の温度は１７
０℃まで上昇した。Then, a pyridine-water mixture (molar ratio 1:10) was introduced into the reactor via a vaporizer, and the light source lamp was turned on. Next, when chlorine is aerated and reacted, the temperature inside the vessel becomes 17
The temperature rose to 0°C.
反応には２時間を要し、この間に使用した原料はそれぞ
れピリジン８５ｇ、水１９３ｇ、塩素８１ｇであった。The reaction required 2 hours, and the raw materials used during this time were 85 g of pyridine, 193 g of water, and 81 g of chlorine.
生成した反応液は２層に分離しており、その下層部分に
は結晶が析出していた。The generated reaction solution was separated into two layers, and crystals were precipitated in the lower layer.
この両層を分析した結果、２，６−ジクロロピリジン４
０．Ｏｇ、２−クロロピリジン１１．７ｇおよび未反応
ピリジン５３．５ｇを含んでいた。As a result of analyzing both layers, 2,6-dichloropyridine 4
0. It contained 11.7 g of Og, 2-chloropyridine and 53.5 g of unreacted pyridine.
２０ｇの濃塩酸を添加し、反応液のｐＨを１以下にした
後、この反応液にクロロベンゼン５００ｍ１を加え９０
℃でよく撹拌後置液した。クロロベンゼン屑には２，６
−ジクロロピリジンが含まれていた。次いで水層に新た
にクロロベンゼン５００ｍ１を加えた後、４０％苛性ソ
ーダ水溶液でｐＨを３とし、よく撹拌後９０℃で分液し
た。クロロベンゼン層には２−クロロピリジンが含まれ
ていた。最後に水層を４０％苛性ソーダでｐＨ１０とし
た後、クロロベンゼン５００ｍ１で抽出するとピリジン
はクロロベンゼン層に抽出分離された。After adding 20 g of concentrated hydrochloric acid to bring the pH of the reaction solution to below 1, 500 ml of chlorobenzene was added to the reaction solution and the pH was adjusted to 90 g.
After stirring well at ℃, the solution was left standing. 2,6 for chlorobenzene waste
- Contains dichloropyridine. Next, 500 ml of chlorobenzene was newly added to the aqueous layer, the pH was adjusted to 3 with a 40% aqueous sodium hydroxide solution, and the layers were separated at 90° C. after thorough stirring. The chlorobenzene layer contained 2-chloropyridine. Finally, the aqueous layer was adjusted to pH 10 with 40% caustic soda, and extracted with 500 ml of chlorobenzene to extract and separate pyridine into a chlorobenzene layer.
各クロロベンゼン層を精留すると２．６−ジクロロピリ
ジン、２−クロロピリジンおよびピリジンが各々３５．
２ ｇ、 ８．５ ｇおよび４８．Ｉｇ得られた。When each chlorobenzene layer is rectified, 2.6-dichloropyridine, 2-chloropyridine, and pyridine are obtained at 35% each.
2 g, 8.5 g and 48. Ig was obtained.
回収率は各々８８．０％、７２．６％、８９．９％であ
った。The recovery rates were 88.0%, 72.6%, and 89.9%, respectively.
（発明の効果）
本発明は、ピリジンと塩素を水を希釈剤として光反応さ
せ、得られた２−クロロピリジン、２．６−ジクロロピ
リジンおよび未反応ピリジンを含む塩素化反応混合液か
ら２，６−ジクロロピリジン。(Effects of the Invention) The present invention photoreacts pyridine and chlorine using water as a diluent, and extracts 2, 6-dichloropyridine.
２−クロロピリジンおよびピリジンを逐次分離する方法
を提供するものである。A method for sequentially separating 2-chloropyridine and pyridine is provided.
本発明により、塩素化反応希釈剤として、四塩化炭素、
トリクロロエチレン、テトラクロロエチレン、テトラク
ロロジフルオロエタン等の安全衛生上、好ましくない含
ハロゲン炭化水素を使用しないで、水を希釈剤として用
いた反応混合液から容易に高純度の２．６−ジクロロピ
リジン、２−クロロピリジンおよびピリジンを効率よく
回収することができる。According to the present invention, carbon tetrachloride,
High purity 2,6-dichloropyridine, 2-chloro can be easily produced from a reaction mixture using water as a diluent without using halogen-containing hydrocarbons such as trichlorethylene, tetrachloroethylene, and tetrachlorodifluoroethane, which are undesirable for health and safety reasons. Pyridine and pyridine can be efficiently recovered.
Claims (3)
得られた２−クロロピリジン、２，６−ジクロロピリジ
ンおよびピリジンを含む塩素化反応混合液から２，６−
ジクロロピリジン、２−クロロピリジンおよびピリジン
を分離する方法において（ａ）塩素化反応混合液のｐＨ
を１以下にした後、有機溶媒で抽出することにより、 ２，６−ジクロロピリジンを分離し、 （ｂ）有機溶媒で抽出した残りの水相のｐＨを２〜５と
した後、有機溶媒で抽出するこ とにより、２−クロロピリジンを分離し、 （ｃ）残された水相のｐＨを７〜１３とした後、有機溶
媒で抽出することにより、ピリジ ンを分離する ことを特徴とする２，６−ジクロロピリジン、２−クロ
ロピリジンおよびピリジンの分離方法。(1) Photoreacting pyridine and chlorine using water as a diluent,
From the obtained chlorination reaction mixture containing 2-chloropyridine, 2,6-dichloropyridine and pyridine, 2,6-
In the method for separating dichloropyridine, 2-chloropyridine and pyridine, (a) the pH of the chlorination reaction mixture;
After reducing the pH to 1 or less, 2,6-dichloropyridine is separated by extraction with an organic solvent. (b) After adjusting the pH of the remaining aqueous phase extracted with an organic solvent to 2 to 5, 2-chloropyridine is separated by extraction; (c) pyridine is separated by adjusting the pH of the remaining aqueous phase to 7 to 13 and then extracting with an organic solvent; A method for separating 6-dichloropyridine, 2-chloropyridine and pyridine.
載の方法。(2) The method according to claim (1), wherein the organic solvent is an aromatic hydrocarbon.
ン、クロロベンゼン、ジクロロベンゼン、トリクロロベ
ンゼンからなる群より選ばれたものである請求項（２）
記載の方法。(3) Claim (2) wherein the aromatic hydrocarbon is selected from the group consisting of benzene, toluene, xylene, chlorobenzene, dichlorobenzene, and trichlorobenzene.
Method described.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8868689A JPH0717606B2 (en) | 1989-04-08 | 1989-04-08 | Method for separating chloropyridines |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8868689A JPH0717606B2 (en) | 1989-04-08 | 1989-04-08 | Method for separating chloropyridines |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02268159A true JPH02268159A (en) | 1990-11-01 |
| JPH0717606B2 JPH0717606B2 (en) | 1995-03-01 |
Family
ID=13949723
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8868689A Expired - Lifetime JPH0717606B2 (en) | 1989-04-08 | 1989-04-08 | Method for separating chloropyridines |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0717606B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5536376A (en) * | 1992-12-28 | 1996-07-16 | Sumitomo Seika Chemicals Co., Ltd. | Method for production of 2-chloropyridine and 2,6-dichloropyridine |
| CN110903160A (en) * | 2019-12-26 | 2020-03-24 | 山东埃森化学有限公司 | Separation and purification method of pyridine chloride and solvent |
| CN114874136A (en) * | 2022-04-30 | 2022-08-09 | 宜昌恒友化工股份有限公司 | Separation method of 2-chloropyridine and 2, 6-dichloropyridine |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108084086B (en) * | 2016-11-21 | 2019-08-02 | 利尔化学股份有限公司 | The post-processing approach of pyridine Light chlorimation mother liquor |
-
1989
- 1989-04-08 JP JP8868689A patent/JPH0717606B2/en not_active Expired - Lifetime
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5536376A (en) * | 1992-12-28 | 1996-07-16 | Sumitomo Seika Chemicals Co., Ltd. | Method for production of 2-chloropyridine and 2,6-dichloropyridine |
| CN110903160A (en) * | 2019-12-26 | 2020-03-24 | 山东埃森化学有限公司 | Separation and purification method of pyridine chloride and solvent |
| CN110903160B (en) * | 2019-12-26 | 2022-06-03 | 山东埃森化学有限公司 | Separation and purification method of pyridine chloride and solvent |
| CN114874136A (en) * | 2022-04-30 | 2022-08-09 | 宜昌恒友化工股份有限公司 | Separation method of 2-chloropyridine and 2, 6-dichloropyridine |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0717606B2 (en) | 1995-03-01 |
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