JPH03271249A - Production of 2,6-naphthalenedicarboxylic acid - Google Patents

Production of 2,6-naphthalenedicarboxylic acid

Info

Publication number
JPH03271249A
JPH03271249A JP2068322A JP6832290A JPH03271249A JP H03271249 A JPH03271249 A JP H03271249A JP 2068322 A JP2068322 A JP 2068322A JP 6832290 A JP6832290 A JP 6832290A JP H03271249 A JPH03271249 A JP H03271249A
Authority
JP
Japan
Prior art keywords
solvent
oxidation
bromine
diethylnaphthalene
reaction
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.)
Pending
Application number
JP2068322A
Other languages
Japanese (ja)
Inventor
Mitsuru Yoshimizu
吉水 満
Haruki Takeuchi
竹内 玄樹
Takeshi Kamei
亀井 武志
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nippon Steel Chemical and Materials Co Ltd
Original Assignee
Nippon Steel Chemical Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Nippon Steel Chemical Co Ltd filed Critical Nippon Steel Chemical Co Ltd
Priority to JP2068322A priority Critical patent/JPH03271249A/en
Publication of JPH03271249A publication Critical patent/JPH03271249A/en
Pending legal-status Critical Current

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Classifications

    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00Technologies relating to chemical industry
    • Y02P20/50Improvements relating to the production of bulk chemicals
    • Y02P20/52Improvements 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

PURPOSE:To obtain the subject compound in high yield at a low cost by using a specific transition metal as a catalyst and optimizing the oxidation condition in the oxidation of 2,6-diethylnaphthalene with molecular oxygen in a specific solvent using a transition metal and bromine as a catalyst. CONSTITUTION:The subject compound useful as a polymeric material, dye intermediate, etc., is produced by oxidizing 2,6-diethylnaphthalene and/or its oxidation intermediate with a gas containing molecular oxygen in a solvent containing >=50wt.% of a <=3C aliphatic monocarboxylic acid using a transition metal and bromine as a catalyst. In the above process, the oxidation is carried out by using >=3 times weight of the solvent based on the raw material and the objective compound in the presence of >=0.1wt.% (based on the solvent) of Co and/or Mn and Ni and/or Ce and >=0.1wt.% (based on the solvent) of bromine at 120-250 deg.C under an oxygen partial pressure of 0.1-20kg/cm<2>.G. The objective compound can be produced in high purity and yield from the above raw material at a low cost.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は2,6〜ナフタレンジカルボン酸を製造する方
法に関するものである。
DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing 2,6-naphthalene dicarboxylic acid.

〔従来の方法〕[Conventional method]

2.6−ナフタレンジカルボン酸は、高分子材料、染料
中間体等として有用な物質である。特に2,6ナフタレ
ンジカルボン酸を構成成分とするポリエステルはポリエ
チレンテレフタレートよりも耐熱性、破断強さ等に優れ
ており、フィルム、食品包装材料等の素材として注目さ
れている。
2.6-Naphthalene dicarboxylic acid is a substance useful as a polymer material, a dye intermediate, and the like. In particular, polyester containing 2,6-naphthalene dicarboxylic acid as a constituent has better heat resistance and breaking strength than polyethylene terephthalate, and is attracting attention as a material for films, food packaging materials, and the like.

従来知られている2、6−ナフタレンジカルボン酸の製
造方法としては、■ナフタレンをメチル化し、その反応
生成物から2,6−シメチルナフタレンを分離して、得
られた2、6−シメチルナフタレンをコバルト、マンガ
ン及び臭素等を触媒に用いて液相酸化する方法、■ナフ
タレンをイソプロピル化し、その反応生成物から2,6
−ジイツプロピルナフタレンを分離して、得られた2、
6−ジイツプロビルナフタレンをコバルト、マンガン及
び臭素等を触媒に用いて液相酸化する方法等がある。
Conventionally known methods for producing 2,6-naphthalene dicarboxylic acid include: (1) methylating naphthalene and separating 2,6-dimethylnaphthalene from the reaction product; A method of liquid phase oxidation of naphthalene using cobalt, manganese, bromine, etc. as a catalyst.
- 2 obtained by separating diitupropylnaphthalene,
There is a method of oxidizing 6-diituprobylnaphthalene in a liquid phase using cobalt, manganese, bromine, etc. as a catalyst.

しかしながら、■の方法では、2,6−ジメチルナフタ
レンの液相酸化は比較的容易に進行するものの、メチル
化反応生成物からの2,6−シメチルナフタレンの分離
が困難であり、逆に、■の方法では、2.6−ジイツプ
ロビルナフタレンの製造は比較的容易であるのに対し、
2,6−ジイツプロビルナフタレンの液相酸化工程で大
量の触媒が必要である、重量収率が悪い等の問題があっ
た。
However, in method (2), although the liquid phase oxidation of 2,6-dimethylnaphthalene proceeds relatively easily, it is difficult to separate 2,6-dimethylnaphthalene from the methylation reaction product; In method (2), 2,6-diituprobylnaphthalene is relatively easy to produce;
In the liquid phase oxidation process of 2,6-diituprobylnaphthalene, there were problems such as a large amount of catalyst being required and a poor weight yield.

一方、ナフタレンをエチル化し、その反応生成物から2
,6−ジエチルナフタレンを分離して、得られた2、6
−ジエチルナフタレンをコバルト、マンガン及び臭素等
を触媒に用いて液相酸化する方法は■、■の方法の持つ
欠点を克服できる可能性があり、有利な方法である。し
かしながら、2,6−ジエチルナフタレンをコバルト、
マンガン等の触媒により液相酸化し、2,6−ナフタレ
ンジカルボン酸を製造する工程における公知の反応例(
特開昭51−6゜953号公報)ではモル収率が77.
3%と低い結果であり、収率の改善が望まれていた。
On the other hand, naphthalene is ethylated and the reaction product is 2
, 6-diethylnaphthalene and the obtained 2,6
- The method of liquid phase oxidation of diethylnaphthalene using cobalt, manganese, bromine, etc. as a catalyst is an advantageous method as it has the possibility of overcoming the drawbacks of methods (1) and (2). However, 2,6-diethylnaphthalene is cobalt,
Known reaction examples (
JP-A No. 51-6゜953), the molar yield was 77.
The result was as low as 3%, and an improvement in the yield was desired.

〔発明が解決しようとする課題〕[Problem to be solved by the invention]

本発明はかかる状況に鑑み、その目的とする所は、ナフ
タレンのエチル化を経由する、より安価な2,6−ナフ
タレンジカルボン酸の製造法を確立するために、2,6
−ジエチルナフタレンから2,6−ナフタレンジカルボ
ン酸を有利に製造する方法を提供することにある。
In view of this situation, the purpose of the present invention is to establish a cheaper method for producing 2,6-naphthalene dicarboxylic acid via ethylation of naphthalene.
An object of the present invention is to provide a method for advantageously producing 2,6-naphthalene dicarboxylic acid from diethylnaphthalene.

〔課題を解決するための手段〕[Means to solve the problem]

本発明者らは、上記方法を確立するために研究を行い、
遷移金属及び臭素等を触媒に用いた液相酸化反応におい
て、遷移金属としてコバルト、マンガン、ニッケル、セ
リウムより選ばれた1種または2種以上の混合物を触媒
に用いれば、2,6−ナフタレンジカルボン酸の収率が
向上することを見出すと共に、その他の酸化条件を最適
化し、本発明を完成した。
The present inventors conducted research to establish the above method,
In a liquid phase oxidation reaction using a transition metal, bromine, etc. as a catalyst, if one or a mixture of two or more selected from cobalt, manganese, nickel, and cerium is used as a catalyst, 2,6-naphthalenedicarbone can be produced. The present invention was completed by discovering that the yield of acid was improved and by optimizing other oxidation conditions.

すなわち、本発明は、2,6−ジエチルナフタレン及び
/又はその酸化中間体を、炭素数が3以下の脂肪族モノ
カルボン酸を少なくとも50重量%含有する溶媒中、遷
移金属及び臭素を触媒として分子状酸素含有ガスにより
酸化するに当たり、2,6−ジエチルナフタレン、その
酸化中間体及び2,6−ナフタレンジカルボン酸に対し
て少なくとも3倍重量の溶媒を使用し、溶媒当たり0.
1重量%以上のコバルト及び/又はマンガンからなる遷
移金属と、ニッケル及びセリウムより選ばれた1種又は
2種の遷移金属並びに溶媒当たり0.1重量%以上の臭
素を存在させ、反応温度120〜250℃、酸素分圧0
.1〜20kg/cd−Gの反応条件で酸化することを
特徴とする2、6−ナフタレンジカルボン酸の製造方法
である。
That is, the present invention provides a method for preparing 2,6-diethylnaphthalene and/or its oxidized intermediate in a solvent containing at least 50% by weight of an aliphatic monocarboxylic acid having 3 or less carbon atoms, using a transition metal and bromine as a catalyst. For oxidation with oxygen-containing gas, at least 3 times the weight of the solvent is used for 2,6-diethylnaphthalene, its oxidized intermediate, and 2,6-naphthalene dicarboxylic acid, and 0.
1% by weight or more of a transition metal consisting of cobalt and/or manganese, one or two transition metals selected from nickel and cerium, and 0.1% by weight or more of bromine per solvent are present, and the reaction temperature is 120~ 250℃, oxygen partial pressure 0
.. This is a method for producing 2,6-naphthalene dicarboxylic acid, characterized in that oxidation is carried out under reaction conditions of 1 to 20 kg/cd-G.

以下、本発明の詳細な説明する。The present invention will be explained in detail below.

本発明で酸化原料として用いる2、6−ジエチルナフタ
レンは、通常、ナフタレンをフリーデルクラフッ触媒を
用いてエチレン、エチルクロライド、ポリエチルベンゼ
ン等のエチル化剤によりエチル化又はトランスエチル化
し、得られたエチル化生成物を蒸留、冷却晶析、圧力晶
析、アダクツ分離、吸着等の分離手段を用いて単離する
ことにより得ることができる。このほかにも、エチル化
されたテトラリンの脱水素、ベンセン環を出発原料とす
る環化等により合成された2、6−ジエチルナフタレン
を酸化原料に用いても良い。これら2,6−ジエチルナ
フタレンは高純度のものが好ましいか、酸化反応終了後
生成物を各種方法で精製した際、除去できる程度であれ
ば、2,6−ジエチルナフタレンおよびその酸化中間体
以外の他の成分、例えば2,7ジエチルナフタレン等を
含んでいても差支えない。
2,6-diethylnaphthalene used as an oxidation raw material in the present invention is usually obtained by ethylating or transethylating naphthalene with an ethylating agent such as ethylene, ethyl chloride, or polyethylbenzene using a Friedel Krach catalyst. It can be obtained by isolating the ethylated product using separation means such as distillation, cooling crystallization, pressure crystallization, adduct separation, and adsorption. In addition, 2,6-diethylnaphthalene synthesized by dehydrogenation of ethylated tetralin, cyclization using a benzene ring as a starting material, etc. may be used as the oxidation raw material. These 2,6-diethylnaphthalenes are preferably of high purity, or if they can be removed by purifying the product after the oxidation reaction by various methods, other than 2,6-diethylnaphthalene and its oxidized intermediates can be used. It may also contain other components such as 2,7 diethylnaphthalene.

また、酸化原料としては少なくとも2,6−ジエチルナ
フタレンを含む原料を用いるが、2,6−ジエチルナフ
タレンのエチル基がホルミル基まで酸化されたものやエ
チル基の一方のみがカルボキシル基まで酸化されたもの
等の酸化中間体をこれに混合してもよい。
In addition, a raw material containing at least 2,6-diethylnaphthalene is used as the oxidation raw material, but 2,6-diethylnaphthalene in which the ethyl group has been oxidized to a formyl group or only one of the ethyl groups has been oxidized to a carboxyl group is used. Oxidized intermediates such as oxidation intermediates may be mixed therein.

本発明で溶媒として使用する炭素数が3以下の脂肪族モ
ノカルボン酸としては、蟻酸、酢酸、プロピオン酸、ブ
ロモ酢酸等を挙げることができるが、酢酸、プロピオン
酸又はそれらの混合物が好ましい。そして、本発明で用
いる溶媒は、これら炭素数が3以下の脂肪族モノカルボ
ン酸を少なくとも50重量以上%、好ましくは70重量
%以上含む。また、溶媒中に多量の水分が存在する場合
は酸化反応を阻害するが、少量であればむしろ良い結果
をもたらす場合もある。その様な溶媒中の水分濃度とし
ては、0〜20重量%、好ましくは0〜10重量%であ
る。
Examples of the aliphatic monocarboxylic acid having 3 or less carbon atoms used as a solvent in the present invention include formic acid, acetic acid, propionic acid, bromoacetic acid, etc., but acetic acid, propionic acid, or a mixture thereof is preferable. The solvent used in the present invention contains at least 50% by weight or more, preferably 70% by weight or more of these aliphatic monocarboxylic acids having 3 or less carbon atoms. Further, if a large amount of water is present in the solvent, the oxidation reaction will be inhibited, but a small amount may actually bring about better results. The water concentration in such a solvent is 0 to 20% by weight, preferably 0 to 10% by weight.

本発明で使用する触媒はコバルト及び/又はマンガンか
らなる遷移金属と、ニッケル、セリウムより選ばれた1
種又は2種の遷移金属並びに臭素である。これらの遷移
金属を反応系内に存在させるには、溶媒に可溶な化合物
として添加すれば良く、その様な化合物としては、遷移
金属の酢酸塩、プロピオン酸塩、ナフテン酸塩、水酸化
物、炭酸塩、臭化物等を挙げることができるが、好まし
くは酢酸塩、プロピオン酸塩、臭化物である。また、臭
素も溶媒に可溶な物質であれば良く、その様な化合物と
しては、分子状臭素、臭化水素、金属臭化物、臭化アル
キル等を挙げることができるが、好ましくは臭化コバル
ト、臭化マンガン、臭化ニッケル、臭化セリウム等の遷
移金属臭化物、臭化カリウム、臭化ナトリウム、臭化リ
チウム等のアルカリ金属臭化物であり、特に好ましくは
、臭化カリウム、臭化ナトリウム、臭化リチウムである
The catalyst used in the present invention is a transition metal consisting of cobalt and/or manganese, and one selected from nickel and cerium.
one or more transition metals and bromine. In order for these transition metals to exist in the reaction system, they can be added as compounds soluble in the solvent, such as transition metal acetates, propionates, naphthenates, and hydroxides. , carbonates, bromides, etc., but acetates, propionates, and bromides are preferred. Further, bromine may be any substance as long as it is soluble in the solvent, and examples of such compounds include molecular bromine, hydrogen bromide, metal bromides, alkyl bromides, etc., but preferably cobalt bromide, cobalt bromide, Transition metal bromides such as manganese bromide, nickel bromide, and cerium bromide; alkali metal bromides such as potassium bromide, sodium bromide, and lithium bromide; particularly preferred are potassium bromide, sodium bromide, and lithium bromide. It is lithium.

これらの触媒の内、コバルト及び/又はマンガンからな
る遷移金属触媒の使用量はその合計濃度が溶媒に対して
0.1重量%以上、好ましくは0゜2重量%以上である
。ニッケル及び/又はセリウムの使用量はその合計濃度
が溶媒に対して0.02重量%以上、好ましくは0.2
重量%以上がよい。臭素の使用量は臭素濃度が溶媒に対
して0゜1重量%以上、好ましくは0.2重量%以上で
ある。ここで、濃度は金属又は臭素に換算した濃度を意
味し、反応系内で金属又は臭素として存在することを意
味するものではない。
Among these catalysts, the total concentration of transition metal catalysts consisting of cobalt and/or manganese is 0.1% by weight or more, preferably 0.2% by weight or more, based on the solvent. The amount of nickel and/or cerium used is such that the total concentration is 0.02% by weight or more, preferably 0.2% by weight based on the solvent.
Weight % or more is preferable. The amount of bromine used is such that the bromine concentration is 0.1% by weight or more, preferably 0.2% by weight or more, based on the solvent. Here, the concentration means the concentration in terms of metal or bromine, and does not mean that it exists as metal or bromine in the reaction system.

そして、これらの触媒が溶媒に溶けた触媒溶液を2,6
−ジエチルナフタレンに対し、3重量倍以上、好ましく
は5重量倍以上用いる。触媒量が不足すると2,6−ナ
フタレンジカルボン酸の収率が低下する。
Then, a catalyst solution in which these catalysts were dissolved in a solvent was mixed with 2,6
- It is used at least 3 times, preferably at least 5 times the weight of diethylnaphthalene. If the amount of catalyst is insufficient, the yield of 2,6-naphthalene dicarboxylic acid will decrease.

反応温度は、120°C〜250℃、好ましくは150
°C〜200°Cの範囲である。反応温度が低いと反応
速度の低下に伴い2,6−ナフタレンジカルボン酸の収
率が低下し、反対に高い場合には副反応生成物が増加し
て、得られる2、6−ナフタレンジカルボン酸の純度が
低下する。
The reaction temperature is 120°C to 250°C, preferably 150°C.
It is in the range of °C to 200 °C. When the reaction temperature is low, the yield of 2,6-naphthalene dicarboxylic acid decreases due to a decrease in the reaction rate; on the other hand, when the reaction temperature is high, side reaction products increase and the yield of 2,6-naphthalene dicarboxylic acid is reduced. Purity decreases.

本発明で使用する分子状酸素含有ガスとしては、酸素ガ
ス、不活性ガスで希釈された分子状酸素等であり、その
酸素濃度はlO〜100体積%、好ましくは15〜10
0体積%である。工業的には空気を使用するのが有利で
ある。また、酸素分圧は、0.1〜20kg/Cr1−
Gの範囲、好ましくは0.1〜10kg/Cr1−G、
更に好ましくは0.5〜5kg/cTl−Gである。反
応圧力は、反応温度において溶媒が液相に保持される様
に設定するが、通常10〜30kg/Cr1−G程度が
適当である。
The molecular oxygen-containing gas used in the present invention is oxygen gas, molecular oxygen diluted with an inert gas, etc., and the oxygen concentration is 10 to 100% by volume, preferably 15 to 10% by volume.
It is 0% by volume. Industrially it is advantageous to use air. In addition, the oxygen partial pressure is 0.1 to 20 kg/Cr1-
G range, preferably 0.1 to 10 kg/Cr1-G,
More preferably, it is 0.5 to 5 kg/cTl-G. The reaction pressure is set so that the solvent is maintained in a liquid phase at the reaction temperature, and is usually about 10 to 30 kg/Cr1-G.

本発明の反応形式では、酸化原料である2、6−ジエチ
ルナフタレン又は2,6−ジエチルナフタレンとその酸
化中間体を連続的に反応系に装入することが有利である
。。この様な反応形式としては、(1)触媒溶液、酸化
原料及び分子状酸素含有ガスを連続的に反応系に装入し
、生成した2、6−ナフタレンジカルボン酸を含むスラ
リー溶液を連続的に抜き出す完全連続方式 (2)触媒溶液は反応前に予め反応系に装入し、反応中
は酸化原料及び分子状酸素含有ガスを連続的に反応系に
装入して反応した後、反応後にまとめて生成した2、6
−ナフタレンジカルボン酸を含むスラリー溶液を抜き出
す半連続方式 がある。これらの方法に対し、反応前に触媒溶液、酸化
原料を予め反応系に装入し、反応中は分子状酸素含有ガ
スのみを連続的に反応系に装入して反応した場合は、昇
温過程及び反応中に2,6−ジエチルナフタレンあるい
はその酸化中間体の濃度が高くなりすぎるため、酸化反
応以外の重合等の副反応の割合が増加し、得られる2、
6−ナフタレンジカルボン酸の純度、収率は低いものと
なる。
In the reaction format of the present invention, it is advantageous to continuously charge the oxidation raw material 2,6-diethylnaphthalene or 2,6-diethylnaphthalene and its oxidized intermediate into the reaction system. . Such a reaction format is as follows: (1) A catalyst solution, an oxidizing raw material, and a molecular oxygen-containing gas are continuously charged into the reaction system, and the generated slurry solution containing 2,6-naphthalene dicarboxylic acid is continuously charged. Completely continuous extraction method (2) The catalyst solution is charged into the reaction system in advance before the reaction, and during the reaction, the oxidation raw material and molecular oxygen-containing gas are continuously charged into the reaction system, reacted, and then collected after the reaction. 2 and 6 generated by
- There is a semi-continuous method for extracting a slurry solution containing naphthalene dicarboxylic acid. In contrast to these methods, if the catalyst solution and oxidation raw material are charged into the reaction system in advance and only molecular oxygen-containing gas is continuously charged into the reaction system during the reaction, the temperature will not increase. Because the concentration of 2,6-diethylnaphthalene or its oxidized intermediate becomes too high during the process and reaction, the proportion of side reactions such as polymerization other than oxidation reactions increases, resulting in
The purity and yield of 6-naphthalene dicarboxylic acid will be low.

酸化反応によって生成した2、6−ナフタレンジカルボ
ン酸は、反応生成物を固液分離することにより固相側に
得ることができる。固液分離によって得られた粗2,6
−ナフタレンジカルボン酸は、酢酸等による洗浄、水洗
浄を行うことにより、付着触媒溶液、酸化反応中間体及
びトリメリット酸触媒金属錯体を除去することができ、
純度アップか可能である。さらに必要な場合は、公知の
方法として知られている通常の2,6−ナフタレンジカ
ルボン酸精製法を用いれば、極めて高純度の2,6−ナ
フタレンジカルボン酸を得ることができる。
The 2,6-naphthalene dicarboxylic acid produced by the oxidation reaction can be obtained on the solid phase side by separating the reaction product into solid and liquid. Crude 2,6 obtained by solid-liquid separation
- By washing naphthalene dicarboxylic acid with acetic acid or the like and washing with water, the attached catalyst solution, oxidation reaction intermediate, and trimellitic acid catalyst metal complex can be removed,
It is possible to improve the purity. Furthermore, if necessary, extremely high purity 2,6-naphthalene dicarboxylic acid can be obtained by using a conventional 2,6-naphthalene dicarboxylic acid purification method known as a known method.

〔実施例〕〔Example〕

以下、実施例に基づいて、本発明を具体的に説明する。 Hereinafter, the present invention will be specifically explained based on Examples.

なお、実施例における部及び%はそれぞれ重量部及び重
量%を示す。
In addition, parts and % in Examples indicate parts by weight and % by weight, respectively.

実施例1〜5 電磁攪拌機付きチタン製加圧容器に第1表に示す触媒溶
液250部を予め装入し、第2表に示す反応温度、反応
圧に保持しながら、純度99%の2.6−ジエチルナフ
タレン及び圧縮空気を連続的に反応器に供給し、酸化反
応を行った。2,6−ジエチルナフタレンは毎時13部
の割合で2時間供給し、2.6−ジエチルナフタレン供
給終了後も、反応器の温度と圧を保持したまま圧縮空気
を15分間供給した。反応終了後は冷却してからスラリ
ー状の反応生成物を濾過して分離し、得られた結晶を酢
酸洗浄、水洗浄後乾燥し、2,6−シエチルナフタレン
を得た。結果を第2表に示す。
Examples 1 to 5 250 parts of the catalyst solution shown in Table 1 was charged in advance into a titanium pressurized container equipped with an electromagnetic stirrer, and while maintaining the reaction temperature and reaction pressure shown in Table 2, 2. 6-Diethylnaphthalene and compressed air were continuously supplied to the reactor to carry out the oxidation reaction. 2,6-diethylnaphthalene was supplied at a rate of 13 parts per hour for 2 hours, and even after the supply of 2,6-diethylnaphthalene was completed, compressed air was supplied for 15 minutes while maintaining the temperature and pressure of the reactor. After the reaction was completed, the slurry-like reaction product was cooled and separated by filtration, and the obtained crystals were washed with acetic acid, washed with water, and then dried to obtain 2,6-ethylnaphthalene. The results are shown in Table 2.

比較例1 電磁攪拌機付きチタン製加圧容器に第1表に示す触媒溶
液190部及び純度99%の2,6−ジエチルナフタレ
ン20部を予め装入し、第2表に示す反応温度、反応圧
に保持しながら、圧縮空気のみを連続的に反応器に供給
し、酸化反応を行った。
Comparative Example 1 190 parts of the catalyst solution shown in Table 1 and 20 parts of 2,6-diethylnaphthalene with a purity of 99% were charged in advance into a titanium pressurized container equipped with an electromagnetic stirrer, and the reaction temperature and reaction pressure shown in Table 2 were charged. The oxidation reaction was carried out by continuously supplying only compressed air to the reactor while maintaining the temperature.

なお、反応時間は2時間である。反応終了後は冷却して
からスラリー状の反応生成物を濾過して分離し、得られ
た結晶を酢酸洗浄、水洗浄後乾燥し、2.6−ジエチル
ナフタレンを得た。結果を第2表に示す。
Note that the reaction time was 2 hours. After the reaction was completed, the slurry-like reaction product was cooled and separated by filtration, and the obtained crystals were washed with acetic acid, washed with water, and then dried to obtain 2,6-diethylnaphthalene. The results are shown in Table 2.

第1表 〔発明の効果〕 本発明の方法によれば、2,6−ジエチルナフタレンか
ら高純度、高収率で2,6−ナフタレンジカルボン酸を
得ることができ、安価な2,6−ナフタレンジカルボン
酸製造方法として、工業的意義は極めて高い。
Table 1 [Effects of the Invention] According to the method of the present invention, 2,6-naphthalenedicarboxylic acid can be obtained from 2,6-diethylnaphthalene with high purity and high yield, and 2,6-naphthalene is inexpensive. It has extremely high industrial significance as a method for producing dicarboxylic acids.

第2表Table 2

Claims (1)

【特許請求の範囲】[Claims] (1)2,6−ジエチルナフタレン及び/又はその酸化
中間体を、炭素数が3以下の脂肪族モノカルボン酸を少
なくとも50重量%含有する溶媒中、遷移金属及び臭素
を触媒として分子状酸素含有ガスにより酸化するに当た
り、2,6−ジエチルナフタレン、その酸化中間体及び
2,6−ナフタレンジカルボン酸に対して少なくとも3
倍重量の溶媒を使用し、溶媒当たり0.1重量%以上の
コバルト及び/又はマンガンからなる遷移金属と、ニッ
ケル及びセリウムより選ばれた1種又は2種の遷移金属
並びに溶媒当たり0.1重量%以上の臭素を存在させ、
反応温度120〜250℃、酸素分圧0.1〜20kg
/cm^2・Gの反応条件で酸化することを特徴とする
2,6−ナフタレンジカルボン酸の製造方法。
(1) 2,6-diethylnaphthalene and/or its oxidized intermediate is mixed with molecular oxygen using a transition metal and bromine as a catalyst in a solvent containing at least 50% by weight of an aliphatic monocarboxylic acid having 3 or less carbon atoms. When oxidizing with gas, at least 3
Using twice the weight of the solvent, 0.1% by weight or more of a transition metal consisting of cobalt and/or manganese per solvent, one or two transition metals selected from nickel and cerium, and 0.1% by weight per solvent. % or more of bromine is present,
Reaction temperature 120-250℃, oxygen partial pressure 0.1-20kg
1. A method for producing 2,6-naphthalene dicarboxylic acid, which comprises oxidizing it under reaction conditions of /cm^2·G.
JP2068322A 1990-03-20 1990-03-20 Production of 2,6-naphthalenedicarboxylic acid Pending JPH03271249A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2068322A JPH03271249A (en) 1990-03-20 1990-03-20 Production of 2,6-naphthalenedicarboxylic acid

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2068322A JPH03271249A (en) 1990-03-20 1990-03-20 Production of 2,6-naphthalenedicarboxylic acid

Publications (1)

Publication Number Publication Date
JPH03271249A true JPH03271249A (en) 1991-12-03

Family

ID=13370475

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2068322A Pending JPH03271249A (en) 1990-03-20 1990-03-20 Production of 2,6-naphthalenedicarboxylic acid

Country Status (1)

Country Link
JP (1) JPH03271249A (en)

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