JPH0137984B2 - - Google Patents
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- Publication number
- JPH0137984B2 JPH0137984B2 JP12776981A JP12776981A JPH0137984B2 JP H0137984 B2 JPH0137984 B2 JP H0137984B2 JP 12776981 A JP12776981 A JP 12776981A JP 12776981 A JP12776981 A JP 12776981A JP H0137984 B2 JPH0137984 B2 JP H0137984B2
- Authority
- JP
- Japan
- Prior art keywords
- aminophenyl
- oxyethylsulfone
- waste liquid
- acetylaminophenyl
- sulfone
- 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.)
- Expired
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- Removal Of Specific Substances (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Description
【発明の詳細な説明】
本発明は４−アセチルアミノフエニル−β−オ
キシエチルスルホンを塩酸又は硫酸を用いて加水
分解し、４−アミノフエニル−β−オキシエチル
スルホンを得る際に発生する水性廃液の処理方法
に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to hydrolysis of 4-acetylaminophenyl-β-oxyethylsulfone using hydrochloric acid or sulfuric acid to obtain 4-aminophenyl-β-oxyethylsulfone. Regarding the processing method.
更に詳しくは、４−アセチルアミノフエニル−
β−オキシエチルスルホンを水性媒体中、塩酸又
は硫酸を触媒して、加水分解反応を行い、酸を中
和したのち４−アミノフエニル−β−オキシエチ
ルスルホンを晶出分離した液などの４−アミノ
フエニル−β−オキシエチルスルホンを含む廃液
に、無水酢酸を添加して廃水中に溶解している４
−アミノフエニル−β−オキシエチルスルホンを
水に難溶性の４−アセチルアミノフエニル−β−
オキシエチルスルホン類に変換して晶出させ回収
するものである。 More specifically, 4-acetylaminophenyl-
4-Aminophenyl such as a liquid obtained by performing a hydrolysis reaction of β-oxyethylsulfone in an aqueous medium with hydrochloric acid or sulfuric acid as a catalyst, neutralizing the acid, and then crystallizing and separating 4-aminophenyl-β-oxyethylsulfone. -Acetic anhydride is added to wastewater containing β-oxyethylsulfone and dissolved in the wastewater 4
-aminophenyl-β-oxyethyl sulfone with poorly soluble 4-acetylaminophenyl-β-
It is converted into oxyethyl sulfones, crystallized and recovered.
４−アミノフエニル−β−オキシエチルスルホ
ンは、Ｃ、Ｉ、リアクテイブ・ブラツク、５など
の公知の反応性染料の重要な中間体である４−ア
ミノフエニル−β−サルフエートエチルスルホン
の原料であり、４−アミノフエニル−β−サルフ
エートエチルスルホンは通常は４−アセチルアミ
ノフエニル−β−オキシエチルスルホンを塩酸ま
たは希硫酸中で加水分解して一度４−アミノフエ
ニル−β−オキシエチルスルホンとして単離し、
これを乾燥したのち濃硫酸中で硫酸エステル化す
る方法で得られる。しかしこの方法において、生
成する４−アミノフエニル−β−オキシエチルス
ルホンの水溶性が大きくて単離が容易でないため
収率の低下をきたし、操作が煩雑になるという欠
点がある。 4-Aminophenyl-β-oxyethylsulfone is a raw material for 4-aminophenyl-β-sulfate ethylsulfone, which is an important intermediate for known reactive dyes such as C, I, reactive black, 5, etc. -Aminophenyl-β-sulfate ethyl sulfone is usually obtained by hydrolyzing 4-acetylaminophenyl-β-oxyethyl sulfone in hydrochloric acid or dilute sulfuric acid and then isolating it as 4-aminophenyl-β-oxyethyl sulfone.
It is obtained by drying this and then converting it into a sulfuric acid ester in concentrated sulfuric acid. However, this method has the disadvantage that the produced 4-aminophenyl-β-oxyethylsulfone has a high water solubility and is not easy to isolate, resulting in a decrease in yield and complicated operations.
４−アセチルアミノフエニル−β−オキシエチ
ルスルホンを希酸中で加水分解すれば反応率は90
〜95％（対理論）に達するが、４−アミノフエニ
ル−β−オキシエチルスルホンの単離収率はせい
ぜい70〜75％にとどまる。と同時にその分離工程
から排出される廃液は産業廃液として汚染性の問
題を生じる。 When 4-acetylaminophenyl-β-oxyethylsulfone is hydrolyzed in dilute acid, the reaction rate is 90
The isolated yield of 4-aminophenyl-β-oxyethylsulfone remains at most 70-75%, although ~95% (vs. theory) is reached. At the same time, the waste liquid discharged from the separation process poses a pollution problem as an industrial waste liquid.
４−アミノフエニル−β−オキシエチルスルホ
ンを含む廃液は、通常の有機物の処理に実施され
ている活性汚泥法などでは殆んど効果がなく、そ
の処理には困難を伴う。 Waste liquid containing 4-aminophenyl-β-oxyethylsulfone is difficult to treat, as activated sludge methods, which are commonly used to treat organic matter, have little effect.
通常、４−アセチルアミノフエニル−β−オキ
シエチルスルホンを加水分解して得られる４−ア
ミノフエニル−β−オキシエチルスルホンは中和
後冷却して析出させ過分離し、水洗して得られ
ているが、この液及び水洗廃液中には４−アミ
ノフエニル−β−オキシエチルスルホンが２〜３
％程度以下の濃度で溶解されている。また同時
に、中和時に生成した無機塩類も含まれていてこ
の廃液から４−アミノフエニル−β−オキシエチ
ルスルホンを回収するため、液及び水洗後の廃
液を濃縮して冷却晶出させて分離した場合、多量
の塩類も共に析出されてくるので回収４−アミノ
フエニル−β−オキシエチルスルホンの純度が低
下する。４−アミノフエニル−β−オキシエチル
スルホン中の塩は除去しないと次の硫酸エステル
化反応で悪影響を及ぼすので、回収物を再使用し
ようとすれば水洗浄による塩除去が必要であり、
ここでまた４−アミノフエニル−β−オキシエチ
ルスルホンは溶出し、結局は回収経費との関係で
４−アミノフエニル−β−オキシエチルスルホン
の充分な回収はなされていないのが現状である。
また有機溶媒による液の抽出分離する方法も考
えられているが、操作が煩雑になり工業的に有利
な方法とはいえない。 Usually, 4-aminophenyl-β-oxyethylsulfone obtained by hydrolyzing 4-acetylaminophenyl-β-oxyethylsulfone is obtained by cooling after neutralization, precipitating, overseparating, and washing with water. However, this liquid and the washing waste liquid contain 2 to 3 4-aminophenyl-β-oxyethyl sulfone.
% or less. At the same time, inorganic salts generated during neutralization are also included, and in order to recover 4-aminophenyl-β-oxyethylsulfone from this waste liquid, the liquid and the waste liquid after washing with water are concentrated and separated by cooling and crystallization. Since a large amount of salts are also precipitated, the purity of the recovered 4-aminophenyl-β-oxyethylsulfone decreases. If the salt in 4-aminophenyl-β-oxyethylsulfone is not removed, it will have an adverse effect on the next sulfuric acid esterification reaction, so if the recovered material is to be reused, it is necessary to remove the salt by washing with water.
Here again, 4-aminophenyl-β-oxyethylsulfone is eluted, and the current situation is that 4-aminophenyl-β-oxyethylsulfone cannot be sufficiently recovered due to the cost of recovery.
A method of extracting and separating the liquid using an organic solvent has also been considered, but this method requires complicated operations and cannot be said to be industrially advantageous.
本発明者らは、上記観点に立ち、４−アセチル
アミノフエニル−β−オキシエチルスルホンを加
水分解し、生成物を晶出分離水洗した後の、
液、水洗浄液に溶存している４−アミノフエニル
−β−オキシエチルスルホンの完全回収を計ると
同時に、４−アミノフエニル−β−オキシエチル
スルホン分離工程から排出される廃液中のCOD
値を低下させるべく、鋭意検討した結果本発明に
到達したものである。 In view of the above, the present inventors hydrolyzed 4-acetylaminophenyl-β-oxyethylsulfone, crystallized the product, separated it, and washed it with water.
At the same time, we aim to completely recover the 4-aminophenyl-β-oxyethylsulfone dissolved in the water washing solution, and at the same time, we aim to completely recover the COD in the waste liquid discharged from the 4-aminophenyl-β-oxyethylsulfone separation process.
The present invention was arrived at as a result of intensive studies aimed at lowering the value.
即ち本発明方法は４−アセチルアミノフエニル
−β−オキシエチルスルホンを加水分解して得ら
れた４−アミノフエニル−β−オキシエチルスル
ホンを含む晶出分離工程より排出される排液に無
水酢酸を等モル比以上添加して廃液中に溶存して
いる４−アミノフエニル−β−オキシエチルスル
ホンをアセチル化し、主に４−アセチルアミノフ
エニル−β−オキシエチルスルホンとして析出さ
せて、分離し、これを４−アセチルアミノフエニ
ル−β−オキシエチルスルホンの加水分解工程へ
回収することを特徴とする４−アミノフエニル−
β−オキシエチルスルホンの分離工程廃液の処理
方法である。 That is, the method of the present invention involves adding acetic anhydride to the waste liquid discharged from the crystallization separation step containing 4-aminophenyl-β-oxyethylsulfone obtained by hydrolyzing 4-acetylaminophenyl-β-oxyethylsulfone. The 4-aminophenyl-β-oxyethylsulfone added in an equimolar ratio or more and dissolved in the waste liquid is acetylated, precipitated mainly as 4-acetylaminophenyl-β-oxyethylsulfone, and separated. 4-aminophenyl-, which is recovered to the hydrolysis step of 4-acetylaminophenyl-β-oxyethylsulfone.
This is a method for treating waste liquid from the separation process of β-oxyethylsulfone.
本発明の方法は、化学変換反応を用い、その反
応生成物の物理的性質を利用したものであり、具
体的には、４−アミノフエニル−β−オキシエチ
ルスルホンの溶存している廃液中に無水酢酸を４
−アミノフエニル−β−オキシエチルスルホンに
対して等モル比以上滴下することにより、４−ア
ミノフエニル−β−オキシエチルスルホンは極め
て希薄水溶液の状態にもかゝわらず、その殆んど
全部が容易にアセチル化されて、廃液中の４−ア
ミノフエニル−β−オキシエチルスルホンは、水
難溶性である４−アセチルアミノフエニル−β−
オキシエチルスルホンやその誘導体であるジアセ
チル化物などに変換されることがわかりこの知見
にもとずくものである。 The method of the present invention uses a chemical conversion reaction and takes advantage of the physical properties of the reaction product. 4 acetic acid
By dropping 4-aminophenyl-β-oxyethylsulfone in an equimolar ratio or more to -aminophenyl-β-oxyethylsulfone, almost all of the 4-aminophenyl-β-oxyethylsulfone can be easily dissolved, even though it is in an extremely dilute aqueous solution state. Acetylated 4-aminophenyl-β-oxyethylsulfone in the waste liquid becomes 4-acetylaminophenyl-β-, which is poorly soluble in water.
This finding is based on the finding that it is converted to oxyethyl sulfone and its derivatives such as diacetylated products.
本発明方法は４−アセチルアミノフエニル−β
−オキシエチルスルホンを酸加水分解して得られ
た４−アミノフエニル−β−オキシエチルスルホ
ンを冷却晶出分離した液及び分離した粗結晶の
水洗浄廃液、あるいはこれらの廃液をさらに濃縮
して晶出分離した液及びその回収粗結晶の水洗
浄廃液のいずれにも適用できるが、本発明処理方
法では廃液中に溶存している４−アミノフエニル
−β−オキシエチルスルホンは殆んど完全に近い
状態で回収でき、また得られた回収物は水洗して
そのまゝ４−アセチルアミノフエニル−β−オキ
シエチルスルホンの加水分解工程に戻すことがで
きるので、４−アセチルアミノフエニル−β−オ
キシエチルスルホンの加水分解工程後の４−アミ
ノフエニル−β−オキシエチルスルホンの晶出、
洗浄の分離工程廃液処理に本発明方法を適用すれ
ば極めて有利である。 The method of the present invention uses 4-acetylaminophenyl-β
- 4-aminophenyl-β-oxyethyl sulfone obtained by acid hydrolysis of oxyethyl sulfone is crystallized by cooling, the separated liquid and the water washing waste liquid of the separated crude crystals, or these waste liquids are further concentrated and crystallized. Although it can be applied to both the separated liquid and the waste liquid from washing the recovered crude crystals with water, in the treatment method of the present invention, the 4-aminophenyl-β-oxyethylsulfone dissolved in the waste liquid is almost completely removed. 4-acetylaminophenyl-β-oxyethyl sulfone can be recovered, and the recovered material can be washed with water and returned to the hydrolysis process of 4-acetylaminophenyl-β-oxyethyl sulfone. Crystallization of 4-aminophenyl-β-oxyethyl sulfone after the sulfone hydrolysis step;
It is extremely advantageous to apply the method of the present invention to waste liquid treatment in the separation step of washing.
本発明方法により、廃液中に溶存している４−
アミノフエニル−β−オキシエチルスルホンは、
無水酢酸を添加することにより主として４−アセ
チルアミノフエニル−β−オキシエチルスルホン
となるが、他に少量の４−アミノフエニル−β−
アセトキシエチルスルホンや４−アセチルアミノ
フエニル−β−アセトキシエチルスルホンのジア
セチル化物も生成される。しかしこれらのアセチ
ル化物は加水分解工程へ戻した場合、高純度の４
−アミノフエニル−β−オキシエチルスルホンに
容易に転化されるので、廃液処理して分離回収し
たアセチル化物は混合物のまゝ加水分解工程へ戻
すことができる。 By the method of the present invention, 4-
Aminophenyl-β-oxyethylsulfone is
By adding acetic anhydride, 4-acetylaminophenyl-β-oxyethylsulfone is mainly produced, but a small amount of 4-aminophenyl-β-
Diacetylated products of acetoxyethyl sulfone and 4-acetylaminophenyl-β-acetoxyethyl sulfone are also produced. However, when these acetylated products are returned to the hydrolysis process, highly pure 4
Since it is easily converted to -aminophenyl-β-oxyethylsulfone, the acetylated product separated and recovered by waste liquid treatment can be returned to the hydrolysis step as a mixture.
本発明方法はこれらの廃液に、廃液中に溶解し
ている４−アミノフエニル−β−オキシエチルス
ルホンの量に対し、無水酢酸を1.0モル比以上好
ましくは２〜４モル比滴下して処理する。無水酢
酸添加量が２モル比以下でも反応は進むが、廃水
中の４−アミノフエニル−β−オキシエチルスル
ホンをより完全に除去回収するためには２モル比
以上の使用量がよい。また４モル比以上では反応
に関与しない無水酢酸から生ずる酢酸が廃水中に
残存し廃水処理上好ましくない。処理温度は10〜
35℃のいわゆる室温で充分であり、無水酢酸を添
加した後は、おだやかな撹拌をおこなうことが望
ましい。所望の無水酢酸を添加し撹拌を続けてい
ると、溶存４−アミノフエニル−β−オキシエチ
ルスルホンはアセチル化物として室温ででも析出
してくるので反応終了後これを分離すればよい。
アセチル化反応生成物は水に対する溶解度がきわ
めて小さいので容易に過、水洗して単離回収す
ることができる。水洗回収された４−アセチルア
ミノフエニル−β−オキシエチルスルホン類を分
離することなくそのまゝ塩酸または硫酸の加水分
解による４−アミノフエニル−β−オキシエチル
スルホンの製造工程へ循環使用でき、それによる
加水分解反応へは何ら悪い影響も与えない。 In the method of the present invention, these waste liquids are treated by adding acetic anhydride dropwise in a molar ratio of 1.0 or more, preferably 2 to 4 molar, based on the amount of 4-aminophenyl-β-oxyethylsulfone dissolved in the waste liquid. Although the reaction proceeds even if the amount of acetic anhydride added is less than 2 molar ratio, in order to more completely remove and recover 4-aminophenyl-β-oxyethylsulfone in wastewater, it is preferable to use an amount of acetic anhydride in a molar ratio of 2 or more. Moreover, if the molar ratio is more than 4, acetic acid generated from acetic anhydride that does not participate in the reaction will remain in the wastewater, which is not preferable in terms of wastewater treatment. Processing temperature is 10~
A so-called room temperature of 35°C is sufficient, and it is desirable to perform gentle stirring after adding acetic anhydride. When the desired acetic anhydride is added and stirring is continued, dissolved 4-aminophenyl-β-oxyethylsulfone precipitates out as an acetylated product even at room temperature, so it may be separated after the reaction is completed.
Since the acetylation reaction product has extremely low solubility in water, it can be easily isolated and recovered by filtering and washing with water. The 4-acetylaminophenyl-β-oxyethylsulfones recovered by washing with water can be recycled as they are to the production process of 4-aminophenyl-β-oxyethylsulfone by hydrolysis with hydrochloric acid or sulfuric acid without separation. does not have any adverse effect on the hydrolysis reaction.
以上のように本発明処理法により、廃水中の４
−アミノフエニル−β−オキシエチルスルホンは
殆んど完全に分離できるので、分離工程廃液中の
COD値は著しく低減され４−アミノフエニル−
β−オキシエチルスルホンを含む廃水処理は非常
に効率的な処理ができる。無水酢酸のアセチル化
により生じ廃水中に含有される酢酸は分子内にＳ
原子を有していないので４−アミノフエニル−β
−オキシエチルスルホンと較べて通常の活性汚泥
槽で容易に除去できる。 As described above, by the treatment method of the present invention, 4
-Aminophenyl-β-oxyethylsulfone can be almost completely separated, so
The COD value was significantly reduced and 4-aminophenyl-
Treatment of wastewater containing β-oxyethyl sulfone can be carried out very efficiently. Acetic acid produced by acetylation of acetic anhydride and contained in wastewater contains S in the molecule.
4-aminophenyl-β because it has no atoms
-Easy to remove in a normal activated sludge tank compared to oxyethyl sulfone.
次に本発明の方法を実施例によつて更に具体的
に説明する。例中の部は重量部をあらわす。 Next, the method of the present invention will be explained in more detail with reference to Examples. Parts in the examples represent parts by weight.
実施例
４−アセチルアミノフエニル−β−オキシエチ
ルスルホン（乾燥品）217部および希塩酸730部を
加熱撹拌して加水分解した。次いで20％苛性ソー
ダ水で中和（PH７）してから５℃に冷却して４−
アミノフエニル−β−オキシエチルスルホンを析
出させ、析出物を過し、少量の冷水で洗浄し
た。液、洗浄液を合わせて廃液980部
（COD31000ppm）を得た。Example 217 parts of 4-acetylaminophenyl-β-oxyethylsulfone (dry product) and 730 parts of dilute hydrochloric acid were heated and stirred for hydrolysis. Next, it was neutralized (PH7) with 20% caustic soda water, cooled to 5°C, and 4-
Aminophenyl-β-oxyethylsulfone was precipitated and the precipitate was filtered and washed with a small amount of cold water. A total of 980 parts of waste liquid (COD 31000 ppm) was obtained by combining the liquid and washing liquid.
廃液の一部をサンプリングして、ジアゾ価測定
により、廃水中の４−アミノフエニル−β−オキ
シエチルスルホンの含有率は2.41重量％の結果で
あつた。 A portion of the wastewater was sampled and the diazo value was measured, and the content of 4-aminophenyl-β-oxyethylsulfone in the wastewater was found to be 2.41% by weight.
この廃液980部（４−アミノフエニル−β−オ
キシエチルスルホン23.6部相当を含む）に無水酢
酸36部（3.0モル比）を１時間かけて滴下し、添
加後さらに３時間ゆつくりかきまぜた後、析出し
た結晶物を過分離して生成アセチル化物25.1部
（乾燥品換算）が得られ、液のCODは
11000ppmに低減した。また４−アミノフエニル
−β−オキシエチルスルホンの回収率は90％に相
当し、回収アセチル化物は水洗後加水分解工程に
戻して使用したら高純度の４−アミノフエニル−
β−オキシエチルスルホンが得られ、反応に影響
はなかつた。 36 parts of acetic anhydride (3.0 molar ratio) was added dropwise to 980 parts of this waste liquid (containing the equivalent of 23.6 parts of 4-aminophenyl-β-oxyethylsulfone) over 1 hour. By over-separating the crystalline product, 25.1 parts of the acetylated product (dry product equivalent) was obtained, and the COD of the liquid was
Reduced to 11000ppm. Furthermore, the recovery rate of 4-aminophenyl-β-oxyethylsulfone was equivalent to 90%, and if the recovered acetylated product was washed with water and returned to the hydrolysis process for use, highly pure 4-aminophenyl-
β-oxyethyl sulfone was obtained and the reaction was not affected.
Claims (1)
チルスルホンを加水分解して得られた４−アミノ
フエニル−β−オキシエチルスルホンを含む晶出
分離工程より排出される廃液に、無水酢酸を、廃
液中に含まれる４−アミノフエニル−β−オキシ
エチルスルホンに対し１モル比以上添加して、廃
液中に溶存している４−アミノフエニル−β−オ
キシエチルスルホンをアセチル化して分離回収す
ることを特徴とする４−アミノフエニル−β−オ
キシエチルスルホンの分離工程廃液の処理方法。 ２ 無水酢酸の添加量が廃液中の４−アミノフエ
ニル−β−オキシエチルスルホンに対し、２〜４
モル比である特許請求の範囲第１項記載の方法。[Scope of Claims] 1. The waste liquid discharged from the crystallization separation process containing 4-aminophenyl-β-oxyethylsulfone obtained by hydrolyzing 4-acetylaminophenyl-β-oxyethylsulfone is anhydrous. Add acetic acid at a molar ratio of 1 or more to 4-aminophenyl-β-oxyethylsulfone contained in the waste liquid to acetylate and separate and recover the 4-aminophenyl-β-oxyethyl sulfone dissolved in the waste liquid. A method for treating a waste liquid from a separation process of 4-aminophenyl-β-oxyethylsulfone, characterized in that: 2 The amount of acetic anhydride added is 2 to 4 to 4-aminophenyl-β-oxyethyl sulfone in the waste liquid.
A method according to claim 1, wherein the molar ratio is a molar ratio.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12776981A JPS5830388A (en) | 1981-08-17 | 1981-08-17 | Treatment of waste liquid of separating stage for 4-aminophenyl-beta-oxyethylsulfone |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12776981A JPS5830388A (en) | 1981-08-17 | 1981-08-17 | Treatment of waste liquid of separating stage for 4-aminophenyl-beta-oxyethylsulfone |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5830388A JPS5830388A (en) | 1983-02-22 |
| JPH0137984B2 true JPH0137984B2 (en) | 1989-08-10 |
Family
ID=14968233
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12776981A Granted JPS5830388A (en) | 1981-08-17 | 1981-08-17 | Treatment of waste liquid of separating stage for 4-aminophenyl-beta-oxyethylsulfone |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5830388A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103756359B (en) * | 2013-12-25 | 2016-03-02 | 浙江劲光实业股份有限公司 | A kind for the treatment of process of p-β hydroxyethyl sulfone Acetanilide mother liquor waste water |
-
1981
- 1981-08-17 JP JP12776981A patent/JPS5830388A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5830388A (en) | 1983-02-22 |
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