JP2638764B2 - Method for recovering 2,6-diisopropylnaphthalene as an inclusion compound with β-cyclodextrin - Google Patents
Method for recovering 2,6-diisopropylnaphthalene as an inclusion compound with β-cyclodextrinInfo
- Publication number
- JP2638764B2 JP2638764B2 JP2512689A JP2512689A JP2638764B2 JP 2638764 B2 JP2638764 B2 JP 2638764B2 JP 2512689 A JP2512689 A JP 2512689A JP 2512689 A JP2512689 A JP 2512689A JP 2638764 B2 JP2638764 B2 JP 2638764B2
- Authority
- JP
- Japan
- Prior art keywords
- dipn
- diisopropylnaphthalene
- cyclodextrin
- inclusion compound
- naphthalene
- 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 - Lifetime
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C7/00—Purification; Separation; Use of additives
- C07C7/148—Purification; Separation; Use of additives by treatment giving rise to a chemical modification of at least one compound
- C07C7/152—Purification; Separation; Use of additives by treatment giving rise to a chemical modification of at least one compound by forming adducts or complexes
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Analytical Chemistry (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Water Supply & Treatment (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Description
【発明の詳細な説明】 ［産業上の利用分野］ 本発明は、2,6−２ジイソプロピルナフタレンを含む
混合物から、該化合物をβ−シクロデキストリンとの包
接化合物として回収する方法に関する。The present invention relates to a method for recovering a compound containing 2,6-diisopropylnaphthalene as an inclusion compound with β-cyclodextrin from a mixture containing 2,6-diisopropylnaphthalene.
［従来の技術］ 2,6−２ジイソプロピルナフタレン（以下2,6−DIPNと
呼ぶことがある）は最近、高度の弾性特性と共に優れた
引張強度と耐熱性を有するポリエチレンナフタレート繊
維や、フィルムの重要な原料である2,6−ナフタレンジ
カルボン酸の原料化合物として注目されている。[Prior art] 2,6-Diisopropylnaphthalene (hereinafter sometimes referred to as 2,6-DIPN) has recently been used in polyethylene naphthalate fibers and films having high elastic properties and excellent tensile strength and heat resistance. It is attracting attention as a starting compound for 2,6-naphthalenedicarboxylic acid, which is an important starting material.
2,6−DIPNは、AlCl3、BF3等のフリーデルクラフツ触
媒、H2SO4、HF等の酸触媒、シリカ−アルミナ、ゼオラ
イト等の固体酸触媒等の公知のアルキル化触媒の存在下
にナフタレン及び／又はモノイソプロピルナフタレンに
プロピレン及び／又はポリイソプロピルベンゼン類を反
応させるアルキル化反応またはトランスアルキル化反応
によって得られる。2,6-DIPN can be obtained in the presence of a known alkylation catalyst such as a Friedel Crafts catalyst such as AlCl 3 and BF 3 , an acid catalyst such as H 2 SO 4 and HF, and a solid acid catalyst such as silica-alumina and zeolite. Or a transalkylation reaction in which propylene and / or polyisopropylbenzenes are reacted with naphthalene and / or monoisopropyl naphthalene.
しかしこの反応生成物中には未反応ナフタレン、モノ
イソプロピルナフタレン、2,6体以外のジイソプロピル
ナフタレン、トリイソプロピルナフタレン等の不純物が
含有され、目的とする2,6−DIPNの含有率は通常20〜30w
t％である。このような不純物を多く含んだ反応生成物
から2,6−DIPNを分離する方法として、蒸留により2,6−
DIPNリッチな留分を回収し、冷却晶析等により融点の高
い2,6−DIPNを分離する方法（特公昭56−2532号公報）
が報告されている。しかしながら、この2,6−DIPNリッ
チ留分中には2,6−DIPNと沸点が近似した2,7−ジイソプ
ロピルナフタレン（以下2,7−DIPNと呼ぶことがある）
がほぼ1:1の割合で存在する。このため、留分中の2,6−
DIPN濃度は40〜50％程度が限界であり、この2,6−DIPN
リッチな留分を引き続いて冷却晶析や溶剤晶析工程にか
ける必要があるが晶析には−10℃程度の低温が必要であ
り、また、晶析を行なっても、濾液側に逃げる2,6−DIP
Nの量が多く、晶析による回収率は50〜60％と低い。そ
して濾液中の2,6−DIPNを更に回収しようとすれば、一
旦2,6−DIPN濃度を上げてから晶析工程にかけなければ
ならないが、2,7−DIPNを含有する濾液中の2,6−DIPN濃
度を高めるためには、異性化処理しなければならない。
濾液中の2,6−DIPNを回収する方法として、これをトリ
及びテトライソプロピルナフタレンを主とする高沸点留
分及びナフタレン及び／又はモノイソプロピルナフタレ
ンを加えてトランスアルキル化工程の原料として循環使
用する方法（特開昭62−226931号公報）も提案されてい
るが、この方法においては2,6−DIPN等を大量に循環さ
せるので、経済的に有利な方法ではない。However, this reaction product contains impurities such as unreacted naphthalene, monoisopropyl naphthalene, diisopropyl naphthalene other than 2,6 isomers, and triisopropyl naphthalene. 30w
t%. As a method for separating 2,6-DIPN from a reaction product containing a large amount of such impurities, 2,6-DIPN is separated by distillation.
A method of recovering a DIPN-rich fraction and separating 2,6-DIPN having a high melting point by cooling crystallization or the like (Japanese Patent Publication No. 56-2532)
Have been reported. However, in this 2,6-DIPN-rich fraction, 2,7-diisopropylnaphthalene having a boiling point close to that of 2,6-DIPN (hereinafter sometimes referred to as 2,7-DIPN)
Exist in a ratio of approximately 1: 1. For this reason, 2,6-
The limit of DIPN concentration is about 40-50%, and this 2,6-DIPN
The rich fraction must be subsequently subjected to a cooling crystallization or solvent crystallization step, but crystallization requires a low temperature of about −10 ° C., and even if crystallization is performed, it escapes to the filtrate side. , 6-DIP
The amount of N is large, and the recovery by crystallization is as low as 50-60%. Then, in order to further recover 2,6-DIPN in the filtrate, the 2,6-DIPN concentration must be increased once and then subjected to the crystallization step.However, the 2,6-DIPN in the filtrate containing 2,7-DIPN is required to be recovered. In order to increase the concentration of 6-DIPN, an isomerization treatment must be performed.
As a method for recovering 2,6-DIPN in the filtrate, a high-boiling fraction mainly composed of tri- and tetraisopropylnaphthalene and naphthalene and / or monoisopropylnaphthalene are added to be recycled and used as a raw material in a transalkylation step. Although a method (JP-A-62-226931) has also been proposed, this method is not economically advantageous because 2,6-DIPN and the like are circulated in large quantities.
［発明が解決しようとする課題］ 本発明は2,6−ジイソプロピルナフタレンを含む混合
物から、精密蒸留、冷却晶析のような従来の工業的精製
法よりも簡便な方法で、これまで分離が困難とされてい
た2,7−DIPNなどを効率的に除去して、2,6−DIPNを回収
する方法を提供することを目的とする。本発明により、
精密蒸留による2,6−DIPNリッチ油の回収や冷却晶析に
おける加熱溶解→冷却という煩わしい工程を省けると共
に回収率を向上できるものとなった。[Problems to be Solved by the Invention] The present invention is a simpler method than a conventional industrial purification method such as precision distillation and cooling crystallization, and has been difficult to separate from a mixture containing 2,6-diisopropylnaphthalene. It is an object of the present invention to provide a method for recovering 2,6-DIPN by efficiently removing 2,7-DIPN and the like. According to the present invention,
The recovery of 2,6-DIPN rich oil by precision distillation and the troublesome process of heat dissolution → cooling in cooling crystallization can be omitted and the recovery rate can be improved.
［課題を解決するための手段］ 本発明者らは、2,6−ジイソプロピルナフタレンを含
む混合物から該化合物を効率よく回収する方法について
鋭意研究を重ねた結果、β−シクロデキストリンが2,6
−DIPNと包接化合物を生成し、その生成定数が他の包接
錯体（特に2,7−DIPN錯体）のそれに比べて大きいこと
を見出し、この知見に基づいて本発明をなすに至った。Means for Solving the Problems The present inventors have conducted intensive studies on a method for efficiently recovering the compound from a mixture containing 2,6-diisopropylnaphthalene, and as a result, β-cyclodextrin was found to be 2,6.
An inclusion compound was formed with -DIPN, and the formation constant was found to be larger than that of other inclusion complexes (particularly, 2,7-DIPN complex), and the present invention was accomplished based on this finding.
すなわち、本発明は、2,6−ジイソプロピルナフタレ
ンを含む混合物とβ−シクロデキストリン溶液を接触さ
せて2,6−ジイソプロピルナフタレンとβ−シクロデキ
ストリンとの包接化合物を生成させ、これを分離するこ
とを特徴とする2,6−ジイソプロピルナフタレンをβ−
シクロデキストリンとの包接化合物として回収する方法
を提供するものである。That is, the present invention comprises contacting a mixture containing 2,6-diisopropylnaphthalene with a β-cyclodextrin solution to form an inclusion compound of 2,6-diisopropylnaphthalene and β-cyclodextrin, and separating the inclusion compound. 2,6-diisopropylnaphthalene characterized by β-
It is intended to provide a method for recovering as an inclusion compound with cyclodextrin.
本発明においては、β−シクロデキストリンを水に溶
解あるいは懸濁させ、この液に2,6−DIPNリッチ留分な
どの2,6−ジイソプロピルナフタレン含有原料を加え、
激しく撹拌する。β−シクロデキストリンの濃度は0.5
〜1.5％が適当である。β−シクロデキストリン水溶液
と2,6−DIPN含有原料の混合割合は、β−シクロデキス
トリンのモル数が2,6−DIPNのそれの0.5〜10倍になるよ
うにする。撹拌はできるだけ激しく行うことが好まし
く、数十分から数時間行う。なお、温度は常温でも良い
が反応速度の点からは、加温、例えば25〜45℃程度にす
るのがよい。混合液はシクロデキストリン包接化合物の
生成により白濁する。撹拌終了後、反応生成物をろ過
し、水にて洗浄後、アセトンで洗浄乾燥することによっ
て、白色固体の包接化合物を得る。この白色固体中に
は、2,6−DIPN以外の有機化合物の包接化合物も含まれ
ているので、これらをいったん60〜70℃以上の熱水中で
解離させた後、再び包接化を繰り返すことによって、2,
6−DIPNの純度を高めることもできる。In the present invention, β-cyclodextrin is dissolved or suspended in water, and a 2,6-diisopropylnaphthalene-containing raw material such as a 2,6-DIPN-rich fraction is added to the solution,
Stir vigorously. The concentration of β-cyclodextrin is 0.5
~ 1.5% is appropriate. The mixing ratio of the β-cyclodextrin aqueous solution and the 2,6-DIPN-containing raw material is such that the number of moles of β-cyclodextrin is 0.5 to 10 times that of 2,6-DIPN. The stirring is preferably performed as vigorously as possible, for several tens minutes to several hours. The temperature may be room temperature, but from the viewpoint of the reaction rate, it is preferable to heat, for example, to about 25 to 45 ° C. The mixture becomes cloudy due to the formation of the cyclodextrin inclusion compound. After completion of the stirring, the reaction product is filtered, washed with water, washed with acetone and dried to obtain an inclusion compound as a white solid. Since this white solid also includes inclusion compounds of organic compounds other than 2,6-DIPN, these are once dissociated in hot water at 60 to 70 ° C. or higher, and then clathrated again. By repeating, 2,
The purity of 6-DIPN can also be increased.
β−シクロデキストリン−2,6−DIPN包接化合物から
2,6−DIPNを得るには種々の方法を用いることができ
る。例えば、包接化合物を熱水に溶解させ、包接錯体を
解離させた後、解離した2,6−DIPNをジエチルエーテル
等の適当な有機溶媒を用いて抽出する方法や包接化合物
を水に懸濁させ、ジエチルエーテル等の適当な有機溶媒
を加えて振とうし、2,6−DIPNを有機層に抽出する方法
等がある。この有機層から有機溶媒を除去すると、2,6
−DIPNを得ることができる。なお、以上の全ての過程に
おいて、シクロデキストリン分子自体は分解することが
ないので、回収再利用が可能である。From β-cyclodextrin-2,6-DIPN inclusion compound
Various methods can be used to obtain 2,6-DIPN. For example, dissolving the clathrate compound in hot water to dissociate the clathrate complex, and then extracting the dissociated 2,6-DIPN using a suitable organic solvent such as diethyl ether or the clathrate compound in water There is a method of suspending, adding an appropriate organic solvent such as diethyl ether and shaking to extract 2,6-DIPN into the organic layer. When the organic solvent is removed from this organic layer, 2,6
-DIPN can be obtained. In all of the above steps, the cyclodextrin molecule itself does not decompose, so that it can be recovered and reused.
本発明において使用する2,6−DIPN含有原料として
は、アルキル化反応生成物をそのまま用いることもでき
るが、この場合ナフタレン、モノイソプロピルナフタレ
ンも包接化されるため、2,6−DIPNの選択率はあまり良
くない。また、精留により2,6−DIPN留分を得、これを
包接化工程の原料とすると、包接化の選択率は良いが、
蒸留にコストを要することとなる。一方、トリイソプロ
ピルナフタレン類等はβ−シクロデキストリンに殆んど
包接されないので、この現象を利用して、アルキル化反
応生成物から蒸留によりジ置換体よりも低沸点留分のみ
を留去したボトム油を使用すれば、蒸留に要するコスト
も低減できる利点をもつ上、包接化における選択率も高
く、最も有利な方法である。As the 2,6-DIPN-containing raw material used in the present invention, an alkylation reaction product can be used as it is, but in this case, naphthalene and monoisopropylnaphthalene are also included, so that 2,6-DIPN is selected. Rate is not very good. In addition, if a 2,6-DIPN fraction is obtained by rectification and this is used as a raw material for the clathration step, the selectivity for clathration is good,
The distillation would be costly. On the other hand, since triisopropylnaphthalenes and the like are hardly included in β-cyclodextrin, utilizing this phenomenon, only low-boiling fractions were distilled off from the alkylated reaction product by distillation from the di-substituted product. The use of bottom oil has the advantage that the cost required for distillation can be reduced, and also has a high selectivity in clathration, which is the most advantageous method.
また本発明は低濃度の2,6−DIPN含有原料からの2,6−
DIPNの濃縮ができるので、他の精製工程の中間で得られ
た成分、例えば冷却晶析工程の濾液中の2,6−DIPN濃度
を上げることもできるので、他の精製法と組み合わせて
使用することもできる。The present invention also relates to a 2,6-diphenyl compound having a low concentration of 2,6-DIPN.
Since DIPN can be concentrated, it is possible to increase the concentration of components obtained in the middle of other purification steps, for example, the 2,6-DIPN concentration in the filtrate of the cooling crystallization step, so that it is used in combination with another purification method. You can also.
［実施例］ 以下、実施例によって本発明をさらに具体的に説明す
る。[Examples] Hereinafter, the present invention will be described more specifically with reference to Examples.
実施例１ β−シクロデキストリンの１％水溶液50mlに、低沸点
留分および高沸点留分をカットした2,6−DIPNリッチ留
分0.25gを加え、40℃にて２時間激しく撹拌した。反応
生成物をメンブランフィルターでろ過し、水にて洗浄し
た後、アセトンにて洗浄・乾燥した。この包接化合物を
水に懸濁させ、ジエチルエーテルを加え、油水分離を行
った。Example 1 To 50 ml of a 1% aqueous solution of β-cyclodextrin, 0.25 g of a 2,6-DIPN-rich fraction from which a low-boiling fraction and a high-boiling fraction had been cut was added, followed by vigorous stirring at 40 ° C. for 2 hours. The reaction product was filtered with a membrane filter, washed with water, and then washed and dried with acetone. This clathrate was suspended in water, diethyl ether was added, and oil-water separation was performed.
本実施例における主な成分の組成を表−１に示す。こ
れは、ガスクロマトグラフ法で分析したもので、表中の
数字は各成分の面積百分率値である。Table 1 shows the composition of the main components in this example. This was analyzed by gas chromatography, and the numbers in the table are the area percentage values of each component.
表−１から明らかなように、包接化によって2,6−DIP
Nの濃縮が効率的に行なわれており、特に蒸留や晶析で
も分離が困難な2,7−DIPNがよく分離されている。 As is evident from Table 1, 2,6-DIP
The concentration of N is performed efficiently, and 2,7-DIPN, which is difficult to separate even by distillation or crystallization, is well separated.
実施例２ ナフタレンのプロピレンによるアルキル化反応生成物
を蒸留し、ナフタレン、モノイソプロピルナフタレン等
のジイソプロピルナフタレンよりも低沸点留分を留去
し、ボトム油を得た。このボトム油を原料として、実施
例−１と同様の包接化反応を行った。Example 2 An alkylation reaction product of naphthalene with propylene was distilled, and a distillate having a lower boiling point than diisopropylnaphthalene such as naphthalene or monoisopropylnaphthalene was distilled off to obtain a bottom oil. Using this bottom oil as a raw material, the same clathration reaction as in Example 1 was performed.
本実施例における主な成分の組成を表−２に示す。 Table 2 shows the composition of the main components in this example.
本実施例においては原料中にトリ体が多量に含有され
ているにも拘らず、2,6−DIPNの濃縮が支障なく行なわ
れている。 In this example, the 2,6-DIPN was concentrated without any problem, despite the fact that the raw material contained a large amount of the tri-form.
［発明の効果］ 本発明により精密蒸留、冷却晶析のような従来の工業
的精製法よりも簡便な方法で、2,6−ナフタレンジカル
ボン酸の原料として有用な高純度の2,6−DIPNをβ−シ
クロデキストリンとの包接化合物として回収することが
でき、特にこれまで分離が困難とされていて2,7−DIPN
を効率的に除去することが可能となった。[Effects of the Invention] According to the present invention, a high-purity 2,6-DIPN useful as a raw material for 2,6-naphthalenedicarboxylic acid by a simpler method than conventional industrial purification methods such as precision distillation and cooling crystallization. Can be recovered as an inclusion compound with β-cyclodextrin, and 2,7-DIPN
Can be efficiently removed.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 片岡 有信 茨城県鹿島郡鹿島町大字光３番地 住金 化工株式会社鹿島工場内 (56)参考文献 特開 昭63−88141（ＪＰ，Ａ) 特開 平２−76829（ＪＰ，Ａ) 特開 昭64−61438（ＪＰ，Ａ) 特開 昭52−42825（ＪＰ，Ａ) 特開 昭50−96530（ＪＰ，Ａ) 特開 平２−204419（ＪＰ，Ａ) Ｂｕｌｌｅｔｉｎ ｏｆ ｔｈｅ Ｃ ｈｅｍｉｃａｌ Ｓｏｃｉｅｔｙ ｏｆ Ｊａｐａｎ，Ｖｏｌ．61 Ｎｏ．４ Ｐ．1163−1167（1988) ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ashinobu Kataoka 3 Kashima-cho, Kashima-gun, Kashima-gun, Ibaraki Pref. Sumikin Chemical Co., Ltd. Kashima Plant (56) References JP-A 63-88141 JP-A-2-76829 (JP, A) JP-A-64-61438 (JP, A) JP-A-52-42825 (JP, A) JP-A-50-96530 (JP, A) JP-A-2-204419 (JP, A) , A) Bulletin of the Chemical Society of Japan, Vol. 61 No. 4P. 1163-1167 (1988)
Claims (2)
混合物とβ−シクロデキストリン溶液を接触させて2,6
−ジイソプロピルナフタレンとβ−シクロデキストリン
との包接化合物を生成させ、これを分離することを特徴
とする2,6−ジイソプロピルナフタレンをβ−シクロデ
キストリンとの包接化合物として回収する方法。A mixture containing 2,6-diisopropylnaphthalene and a β-cyclodextrin solution are brought into contact with each other for 2,6.
A method for producing 2,6-diisopropylnaphthalene as an inclusion compound with β-cyclodextrin, comprising forming an inclusion compound of diisopropylnaphthalene and β-cyclodextrin and separating the inclusion compound.
混合物が、ナフタレン及び／又はイソプロピルナフタレ
ン類にプロピレンを反応させて得られるアルキル化反応
生成物、及び／又はナフタレン及び／又はイソプロピル
ナフタレン類にイソプロピルナフタレン類及び／又はイ
ソプロピルベンゼン類を反応させて得られるトランスア
ルキル化反応生成物を蒸留し、ジイソプロピルナフタレ
ンより低沸点の留分を留去した蒸留残渣である請求項１
記載の方法。2. A mixture containing 2,6-2 diisopropylnaphthalene is an alkylation reaction product obtained by reacting propylene with naphthalene and / or isopropylnaphthalene, and / or an isopropylate with naphthalene and / or isopropylnaphthalene. A distillation residue obtained by distilling a transalkylation reaction product obtained by reacting naphthalenes and / or isopropylbenzenes, and distilling a distillate having a lower boiling point than diisopropylnaphthalene.
The described method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2512689A JP2638764B2 (en) | 1989-02-03 | 1989-02-03 | Method for recovering 2,6-diisopropylnaphthalene as an inclusion compound with β-cyclodextrin |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2512689A JP2638764B2 (en) | 1989-02-03 | 1989-02-03 | Method for recovering 2,6-diisopropylnaphthalene as an inclusion compound with β-cyclodextrin |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02209818A JPH02209818A (en) | 1990-08-21 |
| JP2638764B2 true JP2638764B2 (en) | 1997-08-06 |
Family
ID=12157254
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2512689A Expired - Lifetime JP2638764B2 (en) | 1989-02-03 | 1989-02-03 | Method for recovering 2,6-diisopropylnaphthalene as an inclusion compound with β-cyclodextrin |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2638764B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117185889B (en) * | 2023-08-25 | 2024-02-06 | 涉县津东经贸有限责任公司 | Industrial production process for preparing diisopropylnaphthalene |
-
1989
- 1989-02-03 JP JP2512689A patent/JP2638764B2/en not_active Expired - Lifetime
Non-Patent Citations (1)
| Title |
|---|
| Ｂｕｌｌｅｔｉｎ ｏｆ ｔｈｅ Ｃｈｅｍｉｃａｌ Ｓｏｃｉｅｔｙ ｏｆ Ｊａｐａｎ，Ｖｏｌ．６１ Ｎｏ．４ Ｐ．１１６３−１１６７（１９８８） |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH02209818A (en) | 1990-08-21 |
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| EXPY | Cancellation because of completion of term |