JPS60239430A - Recovery of hydroxyacetophenone - Google Patents
Recovery of hydroxyacetophenoneInfo
- Publication number
- JPS60239430A JPS60239430A JP9457984A JP9457984A JPS60239430A JP S60239430 A JPS60239430 A JP S60239430A JP 9457984 A JP9457984 A JP 9457984A JP 9457984 A JP9457984 A JP 9457984A JP S60239430 A JPS60239430 A JP S60239430A
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- product
- hydroquinone
- oil
- organic solvent
- boiling point
- Prior art date
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- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
Description
【発明の詳細な説明】
本発明はジイソプロピルベンゼンジヒドロペルオキシド
類(DHPと略称する)の酸分解法によって二価フェノ
ールを製造する際に生ずる高沸点副生油からヒドロキシ
アセトフェノン類(HAと略称する)を効率良く回収す
る方法に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention deals with the production of hydroxyacetophenones (abbreviated as HA) from high-boiling by-product oil produced when dihydric phenols are produced by the acid decomposition method of diisopropylbenzene dihydroperoxides (abbreviated as DHP). The present invention relates to a method for efficiently collecting .
ジイソプロピルベンゼン類を分子状酸素により液相酸化
してDIPとなし、これを酸触媒の存在下で分解してヒ
ドロキノン、レゾルシンを製造することは古くから知ら
れている。上記液相酸化反応においてDHPのみを選択
的に生成させることは難しく、また酸化反応混合物から
高純度のDHPを分離する操作は、煩雑でしかも操作ロ
スを伴なうものであるから、酸分解に供する原料として
DHP以外に、種々の副生物や未反応原料、中間体など
を含む混合物を用いることが行われている。It has been known for a long time that diisopropylbenzenes are oxidized in a liquid phase with molecular oxygen to form DIP, and this is decomposed in the presence of an acid catalyst to produce hydroquinone and resorcinol. It is difficult to selectively generate only DHP in the above liquid phase oxidation reaction, and the operation to separate high-purity DHP from the oxidation reaction mixture is complicated and involves operational loss. In addition to DHP, a mixture containing various by-products, unreacted raw materials, intermediates, etc. is used as a raw material.
・ 従って酸分解によって得られる生成物中には、主生
成物であるヒドロキノン、レゾルシンオヨヒアセトンの
他に、種々の副生物、場合によっては、酸分解に用いら
れた溶媒が含まれている。これらの酸分解反応混合物か
ら、アセトンや該溶媒あるイハさらにイソプロピルフェ
ノール等の低沸点生成物を蒸留によって分離することは
可能である。- Therefore, in addition to the main products hydroquinone and resorcinol oyohyacetone, the products obtained by acid decomposition contain various by-products and, in some cases, the solvent used in acid decomposition. From these acid decomposition reaction mixtures, it is possible to separate low-boiling products such as acetone, the solvent, and isopropylphenol by distillation.
また、該反応混合物からタール分などを含む高沸点副生
物とヒドロキノン、レゾルシンを分離するには、該反応
物に芳香族炭化水素及び水を混合して、ヒドロキノン、
レゾルシン等を水層に溶解させ、一方主として副生物を
芳香族炭化水素層に抽出させて、油水分離により行うこ
とができる。この芳香族炭化水素及び水の添加は、アセ
トン、酸分解に用いられる溶媒あるいはさらに低沸点副
生′ 物を蒸留によって分離する前、蒸留時あるいは蒸
留後のいずれの時期でも行うことができる。In addition, in order to separate hydroquinone and resorcinol from high-boiling byproducts containing tar and the like from the reaction mixture, aromatic hydrocarbons and water are mixed with the reaction mixture, and hydroquinone, resorcinol,
This can be carried out by oil-water separation by dissolving resorcinol and the like in an aqueous layer, while mainly extracting by-products into an aromatic hydrocarbon layer. The aromatic hydrocarbon and water can be added at any time before, during, or after distillation to separate acetone, the solvent used for acid decomposition, or low-boiling byproducts.
また上記油水分離によって芳香族炭化水素層に抽出され
る物質としては、少量の残留ヒドロキノン、レゾルシン
と共にHAや他の副生物、例えばイソプロペニルクメン
(工Peru)
ジイソプロペニルベンゼン(D工PeB)イソプロビル
フェノール(工pp)
1 4ツブ°ピ′アセトフ1′ベニPA)インプロペニ
ルアセトフェノン(工PeA Jインフロベニルフェノ
ール(工per)さらに種々の高沸点縮合物(2量体、
6量体等)がある。In addition, the substances extracted into the aromatic hydrocarbon layer by the oil-water separation include small amounts of residual hydroquinone and resorcin, as well as HA and other by-products, such as isopropenylcumene (Peru), diisopropenylbenzene (D-PeB), isopropylene Vylphenol (pp.
hexamers, etc.).
これらの抽出物質を含む芳香族炭化水素層は蒸留にかけ
られ、留去される芳香族炭化水素は再使用されていたが
、塔底に残留する多くの副生物は、燃料に用いられただ
けであり、この高沸点副生前から特定の成分を回収する
ことは試みられていなし)。The aromatic hydrocarbon layer containing these extracted substances was subjected to distillation, and the aromatic hydrocarbons distilled off were reused, but many of the by-products remaining at the bottom of the column were only used as fuel. However, no attempt has been made to recover specific components from this high boiling point by-product).
本発明者らは、これら高沸点副生油からHAを効率良く
分離して回収する方法について検討した所、以下の事を
認知した。すなわち、p−ジイソプロピルベンゼン(p
−D工PBと略称する)を常法により液相酸化、酸分解
、さらに油水分離して得られる芳香族炭化水素層を蒸留
し、塔底に残留する高沸点副生油を更に減圧蒸留してp
−HAを分離回収する方法について調べた所、塔頂より
留出する高沸点副生油中には融点の高いヒドロキノンが
含まれており、このヒドロキノンが蒸留塔コンデンー中
に析出して、コンデンサーを閉塞するため、蒸留を続行
することができないことeiめた。このため本発明者ら
は、さらに検討した結果′以下の方法を採用すればコン
デンサー等の閉塞も起こらず、しかも連続してHA類を
効率よく回収できることを見出し、本発明に至った。The present inventors studied a method for efficiently separating and recovering HA from these high-boiling byproduct oils, and found the following. That is, p-diisopropylbenzene (p
The aromatic hydrocarbon layer obtained by liquid-phase oxidation, acid decomposition, and oil/water separation is distilled using conventional methods, and the high-boiling byproduct oil remaining at the bottom of the column is further distilled under reduced pressure. Tep
- When we investigated the method for separating and recovering HA, we found that the high-boiling by-product oil distilled from the top of the column contained hydroquinone with a high melting point, and this hydroquinone precipitated in the condensate of the distillation column, causing the condenser to drain. It was assumed that the distillation could not continue due to blockage. Therefore, as a result of further studies, the present inventors discovered that if the following method was adopted, condensers etc. would not be clogged and HAs could be continuously and efficiently recovered, leading to the present invention.
すなわち、DHPの酸分解法による二価のフェノールの
製法において副生ずる高沸点副生前を2Q tnrrに
おける沸点が約70ないし約160℃であって、二価フ
ェノールの良溶媒である非芳香族性の極性有機溶媒と共
に蒸留し、HAを該極性有機溶媒と共に塔頂留分として
取得した後、該HAを単離することを特徴とするHAの
回収方法に関する。That is, in the process of producing dihydric phenol using the acid decomposition method of DHP, a non-aromatic compound having a boiling point of about 70 to about 160°C at 2Q tnrr and which is a good solvent for dihydric phenol is used as a by-product. The present invention relates to a method for recovering HA, which comprises distilling the HA together with a polar organic solvent to obtain HA together with the polar organic solvent as an overhead fraction, and then isolating the HA.
本発明の方法が適用される高沸点副生油は、p−])H
Pおよび/またはm−DHPの酸分解によって得られる
酸分解生成物から蒸留、抽出等の方法でヒドロキノン、
レゾルシン、アセトン等を分離した後の残留物、あるい
はさらに酸分解に用いられた溶媒や低沸点副生物を留去
した後の塔底残留物であり、通常は少量のヒドロキノン
あるいはレゾルシンと共にp−HAあるいはm−HAを
含む。さらには前記した種々の副生物を含む主としてタ
ール状の高沸点副生油である。The high boiling point by-product oil to which the method of the present invention is applied is p-])H
Hydroquinone,
It is the residue after separating resorcinol, acetone, etc., or the bottom residue after distilling off the solvent used for acid decomposition and low-boiling byproducts, and usually contains p-HA along with a small amount of hydroquinone or resorcinol. Or it contains m-HA. Furthermore, it is a high-boiling by-product oil that is mainly tar-like and contains the various by-products mentioned above.
本発明において使用される非芳香族性の極性有機溶媒は
、圧力20torrにおける沸点が約70℃ないし約1
60℃、特に好ましくは約80°Cないし約110℃の
範囲にあり、かつヒドロキノンあるいはレゾルシンの良
溶媒となるものである。圧力2Qtorrにおける沸点
が、約70°Cより低い有機溶媒を用いると、有機溶媒
を蒸留により塔頂から回収する際に、コンデンサーでの
凝縮に冷却熱エネルギーを多量に必要とするため不利で
ある。また、圧力20torrにおける沸点が熱160
℃【越える有機溶媒を用いた場合には、高沸点副生油の
減圧蒸留によって分取されたHA、ヒドロキノンあるい
はレゾルシン、該有機溶媒からなる混合物を蒸留にかけ
、HA以外の成分を留去する際に、有機溶媒の分離が悪
くなる。また、塔頂から回収されるHA以外の成分を、
さらに蒸留にかけて塔底からヒドロキノンあるいはレゾ
ルシンを回収する際に有機溶媒の分離が悪くなる。The non-aromatic polar organic solvent used in the present invention has a boiling point of about 70°C to about 1°C at a pressure of 20 torr.
The temperature is 60°C, particularly preferably in the range of about 80°C to about 110°C, and is a good solvent for hydroquinone or resorcinol. The use of an organic solvent with a boiling point lower than about 70° C. at a pressure of 2 Q torr is disadvantageous because a large amount of cooling heat energy is required for condensation in the condenser when the organic solvent is recovered from the top of the column by distillation. In addition, the boiling point at a pressure of 20 torr is 160
When using an organic solvent that exceeds [℃], HA, hydroquinone or resorcinol separated by vacuum distillation of high-boiling point by-product oil, and a mixture consisting of the organic solvent are distilled to remove components other than HA. In addition, the separation of the organic solvent becomes worse. In addition, components other than HA recovered from the top of the tower are
Furthermore, when hydroquinone or resorcinol is recovered from the bottom of the column by distillation, separation of the organic solvent becomes poor.
以上のことから、有機溶媒はその沸点が、ヒドロキノン
あるいはレゾルシンの沸点より低いものが望ましい。さ
らに通常含まれて・い・るDIPeB等の低沸点副生物
の沸点より低いものを使用すると一回の蒸留操作で有機
溶媒の回収ができ、再使用が可能なため工業的に極めて
有利である。From the above, it is desirable that the organic solvent has a boiling point lower than that of hydroquinone or resorcinol. Furthermore, if a substance with a boiling point lower than that of the low-boiling by-products such as DIPeB that are normally contained is used, the organic solvent can be recovered in a single distillation operation and can be reused, which is extremely advantageous industrially. .
このような有機溶媒として、具体的にはホロン(沸点9
6℃、20torr)、イソホロン(沸点98℃、20
torr)のようなケトン類、エチレングリコール(沸
点106℃、20torr)、プロピレングリコール(
沸点115℃、20torr )、ジエチレングリコー
ル(沸点150℃、20torr )のような多価アル
コール類等が例示できる。Specifically, such organic solvents include holon (boiling point 9
6℃, 20torr), isophorone (boiling point 98℃, 20
torr), ethylene glycol (boiling point 106°C, 20 torr), propylene glycol (
Examples include polyhydric alcohols such as diethylene glycol (boiling point: 115°C, 20 torr) and diethylene glycol (boiling point: 150°C, 20 torr).
有機溶媒の使用割合は、熱エネルギーコスト上少ないこ
とが望ましいが、使用される有機媒体のヒドロキノンあ
るいはレゾルシン溶解度、あるいは高沸点副生油中のH
Aやヒドロキノン、レゾル1 シン等の割合に応じて適
宜その使用割合が調整される。通常は高沸点副生油1o
o重量部あたり約10重量部以上、特に好ましくは約2
0ないし約50重量部使用される。例えば、p−DIP
Bの高沸点副生前処理にイソホロンを使用する場合、副
生油中のヒドロキノンの重量に対して好ましくは2倍以
上、とくに好ましくは4ないし5倍量加えられる。It is desirable that the proportion of organic solvent used be small in terms of thermal energy costs, but the solubility of hydroquinone or resorcin in the organic medium used, or the H
The usage ratio is adjusted as appropriate depending on the ratio of A, hydroquinone, resorcinol, etc. Usually high boiling point by-product oil 1o
o About 10 parts by weight or more, particularly preferably about 2 parts by weight
0 to about 50 parts by weight are used. For example, p-DIP
When isophorone is used in the pretreatment of the high boiling point by-product B, it is preferably added in an amount of 2 times or more, particularly preferably 4 to 5 times the weight of hydroquinone in the by-product oil.
以下本発明を実施例によって更に説明する。The present invention will be further explained below with reference to Examples.
実施例I
P−DIPBの酸化反応生成物を酸分解して得られる酸
分解生成物からア七トンを除いた後、芳香族炭化水素と
水を添加し、ヒドロキノンを水層に溶解させ、高沸点副
生前その他を油層に抽出し、油水分離を行った。この油
層を減圧下で蒸留し、芳香族炭化水素等を留去すること
により、p−)iAと少量のヒドロキノンを含む高沸点
副生油を得た。Example I After removing a7ton from the acid decomposition product obtained by acid decomposition of the oxidation reaction product of P-DIPB, aromatic hydrocarbon and water were added, hydroquinone was dissolved in the aqueous layer, and high The boiling point by-product and other substances were extracted into an oil layer and oil-water separation was performed. This oil layer was distilled under reduced pressure to remove aromatic hydrocarbons and the like, thereby obtaining a high-boiling byproduct oil containing p-)iA and a small amount of hydroquinone.
高沸点副生前は、第1図に示すブaセスにより、各成分
に分離した。高沸点副生前を蒸留塔1に供給して減圧蒸
留によりインブaビルフェノール(IFF)を主成分と
する低沸点物を留去した。Before the high-boiling point by-product was produced, it was separated into each component by the process shown in FIG. The high boiling point by-product was supplied to the distillation column 1, and the low boiling point products mainly composed of inbu-a-virphenol (IFF) were distilled off under reduced pressure.
xpPを留去した後の塔底には下記の組成の副生油が残
留した。A by-product oil having the following composition remained at the bottom of the column after xpP was distilled off.
工pp +、0(wt%)
工PeA +、5(tt )
工PA 0.1(n )
工PeP O,5(〃 )
ヒドロキノン 10.0(/l )
P−HA 8.5(tt )
縮合物(2緻体等) 75.0C// )この副生油1
00重量部に対してイソホロンを40重量部の割合で添
加して、蒸留塔2に供給し塔底温度約230°C1塔頂
温度約160°C1塔頂圧力2Dtorrの条件で蒸留
することにより、塔頂から下記組成の留出物を連続的に
取り出すことができた。Engineering pp +, 0 (wt%) Engineering PeA +, 5 (tt) Engineering PA 0.1 (n) Engineering PePO O, 5 (〃 ) Hydroquinone 10.0 (/l) P-HA 8.5 (tt) Condensate (2 compacts, etc.) 75.0C//) This by-product oil 1
By adding isophorone at a ratio of 40 parts by weight to 00 parts by weight, supplying it to the distillation column 2 and distilling it under the conditions of a bottom temperature of about 230 ° C, a top temperature of about 160 ° C, and a top pressure of 2 Dtorr, A distillate having the following composition could be continuously taken out from the top of the column.
p−HA 9(wt%)
ヒドロキノン +2(//)
イソホロン 44(//)
低沸点副生油(工pp等)TO(〃 )縮合物 50C
I/)
この留出物は、蒸留塔5に供給され、塔底温度熱240
°C1塔頂温度約160℃、塔頂圧力的20torrの
条件で蒸留を行い、塔底側にp−HAを分離した。この
塔底側のp−HAは精製のためさらに蒸留塔4に供給し
、塔底温度約250’C、塔頂温度約200℃、塔頂圧
力50torrの条件で蒸留し、塔頂から温度約50%
のp−HAを収率約90%で回収した。p-HA 9 (wt%) Hydroquinone +2 (//) Isophorone 44 (//) Low boiling point by-product oil (PP, etc.) TO (〃) condensate 50C
I/) This distillate is fed to the distillation column 5 and has a bottom temperature of 240
Distillation was carried out under conditions of a tower top temperature of about 160° C. and a tower top pressure of 20 torr, and p-HA was separated at the bottom of the tower. The p-HA on the bottom side of the column is further supplied to the distillation column 4 for purification, and distilled under the conditions of a bottom temperature of about 250'C, a top temperature of about 200°C, and a top pressure of 50 torr. 50%
of p-HA was recovered with a yield of about 90%.
さらに、この留出液にトルエンを加えて晶析することに
より純度98%以上、融点108ないし109°Cを有
する、はとんど白色のp−HA結晶が得られた。Furthermore, by adding toluene to this distillate and crystallizing it, almost white p-HA crystals with a purity of 98% or more and a melting point of 108 to 109°C were obtained.
また蒸留塔6の塔頂から回収されたヒドロキノン、イソ
ホロン、あるいはDIPeB、工PP等の低沸点副生油
などを含む留出物を蒸留塔5に供給し、塔底温度約20
0”C,塔頂温度約125°c1塔頂圧力約50tor
rの条件で蒸留し、塔頂がら純度90%以上のイソホロ
ンを約98%回収した。また塔底がらはヒドロキノン、
低沸点副生油等が回収できた。Further, the distillate containing hydroquinone, isophorone, or low-boiling by-product oils such as DIPeB and polypropylene recovered from the top of the distillation column 6 is supplied to the distillation column 5, and the bottom temperature of the column is about 20.
0"C, tower top temperature approx. 125°C1 tower top pressure approx. 50 torr
Distillation was carried out under conditions of r, and about 98% of isophorone with a purity of 90% or more was recovered from the top of the column. In addition, the bottom of the tower contains hydroquinone,
Low boiling point by-product oil etc. were recovered.
実施例2
実施例1と同じ原料を使用し、第1図に示した蒸留塔2
への供給に際し、蒸留塔1の塔底液100重量部に対し
て20重量部の割合でジエチレングリコールを添加した
。その結果蒸留塔2の塔頂温度が約200°C1塔頂圧
力が約IQtor二、蒸留塔5の塔頂温度が約200℃
、塔頂圧力が約IQtorrとなった外は全く同様にp
−HAが回収できた。Example 2 The same raw materials as in Example 1 were used, and the distillation column 2 shown in FIG.
Upon supply to the distillation column 1, diethylene glycol was added at a ratio of 20 parts by weight to 100 parts by weight of the bottom liquid of the distillation column 1. As a result, the top temperature of distillation column 2 is about 200°C, the top pressure is about IQtor2, and the top temperature of distillation column 5 is about 200°C.
, p is exactly the same except that the top pressure is about IQtorr.
-HA could be recovered.
蒸留塔5の塔頂液は蒸留塔5に供給して蒸留を行った。The top liquid of the distillation column 5 was supplied to the distillation column 5 for distillation.
その結果、塔頂からジエチレングリコールが濃度78%
、回収率96%で回収できた。As a result, diethylene glycol was found at the top of the tower at a concentration of 78%.
, with a recovery rate of 96%.
比較例
実施例1と同じ原料を用いて溶媒を使用せず同様の蒸留
操作を行った。その結果、第1図に示した蒸留塔2にお
いてヒドロキノンの析出を防止するためコンデンサー温
度を140℃まで上昇させたが、それでもコンデンサー
の閉塞及び塔頂部に! おいてヒドロキノンの析出を防
ぐことかできず、運転を継続するこVS不可能であった
。Comparative Example The same distillation operation as in Example 1 was carried out using the same raw materials and without using a solvent. As a result, in order to prevent the precipitation of hydroquinone in the distillation column 2 shown in Fig. 1, the condenser temperature was raised to 140°C, but the condenser was still clogged and the top of the column remained! However, the precipitation of hydroquinone could not be prevented, and it was impossible to continue operation.
第1図に本発明の方法の一例を示す工程図を示した。図
中1から5はいずれも蒸留塔を示す。
a・・・高沸点副生油 b・・・イソホロン、C・・・
イソプロピルフェノール
d・・′・縮合物 e・・・p−HA
f・、・イソホロン g・−・ヒドロキノン出願人 三
井石油化学工業株式会社
代理人 山 口 和FIG. 1 shows a process diagram showing an example of the method of the present invention. In the figure, 1 to 5 all indicate distillation columns. a... High boiling point by-product oil b... Isophorone, C...
Isopropylphenol d...' condensate e...p-HA f...isophorone g...hydroquinone Applicant Mitsui Petrochemical Industries Co., Ltd. Agent Kazu Yamaguchi
Claims (1)
の酸分解法による二価フェノールの製法において副生ず
る高沸点副生油を、20 torrにおける沸点が70
ないし160°Cであって、二価フェノールの良溶媒で
ある非芳香族性の極性有機溶媒と共に蒸留し、該副生油
中に含まれるヒドロキシアセトフェノン類を該極性有機
溶媒と共に塔頂留分として取得した後、該ヒドロキシア
セトフェノン類を単離することを特徴とするヒドロキシ
アセトフェノン類の回収方法。(1) High-boiling by-product oil produced in the method of producing dihydric phenol by the acid decomposition method of diisopropylbenzene hydroperoxides is
to 160°C, distilled together with a non-aromatic polar organic solvent that is a good solvent for dihydric phenol, and hydroxyacetophenones contained in the by-product oil are distilled together with the polar organic solvent as an overhead fraction. A method for recovering hydroxyacetophenones, which comprises isolating the hydroxyacetophenones after the hydroxyacetophenones have been obtained.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP9457984A JPS60239430A (en) | 1984-05-14 | 1984-05-14 | Recovery of hydroxyacetophenone |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP9457984A JPS60239430A (en) | 1984-05-14 | 1984-05-14 | Recovery of hydroxyacetophenone |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS60239430A true JPS60239430A (en) | 1985-11-28 |
JPH0460097B2 JPH0460097B2 (en) | 1992-09-25 |
Family
ID=14114189
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP9457984A Granted JPS60239430A (en) | 1984-05-14 | 1984-05-14 | Recovery of hydroxyacetophenone |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS60239430A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2010110482A1 (en) * | 2009-03-25 | 2010-09-30 | 住友化学株式会社 | Method of purifying dihydroxybenzene |
-
1984
- 1984-05-14 JP JP9457984A patent/JPS60239430A/en active Granted
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2010110482A1 (en) * | 2009-03-25 | 2010-09-30 | 住友化学株式会社 | Method of purifying dihydroxybenzene |
JP2010248180A (en) * | 2009-03-25 | 2010-11-04 | Sumitomo Chemical Co Ltd | Process for purification of dihydroxybenzene |
CN102438973A (en) * | 2009-03-25 | 2012-05-02 | 住友化学株式会社 | Method of purifying dihydroxybenzene |
US8530705B2 (en) | 2009-03-25 | 2013-09-10 | Sumitomo Chemical Company, Limited | Purification method of dihydroxybenzene |
Also Published As
Publication number | Publication date |
---|---|
JPH0460097B2 (en) | 1992-09-25 |
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