JPH07101906A - Production of dimethyl 2,6-naphthalenedicarboxylate - Google Patents
Production of dimethyl 2,6-naphthalenedicarboxylateInfo
- Publication number
- JPH07101906A JPH07101906A JP5249522A JP24952293A JPH07101906A JP H07101906 A JPH07101906 A JP H07101906A JP 5249522 A JP5249522 A JP 5249522A JP 24952293 A JP24952293 A JP 24952293A JP H07101906 A JPH07101906 A JP H07101906A
- Authority
- JP
- Japan
- Prior art keywords
- naphthalenedicarboxylic acid
- manganese
- dimethyl
- cobalt
- 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.)
- Granted
Links
Classifications
-
- Y—GENERAL 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
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts
Landscapes
- Catalysts (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
Description
【0001】[0001]
【産業上の利用分野】本発明は、高機能性ポリエステル
原料として有用な2,6−ナフタレンジカルボン酸ジメ
チルを製造する方法に関する。FIELD OF THE INVENTION The present invention relates to a method for producing dimethyl 2,6-naphthalenedicarboxylate which is useful as a raw material for highly functional polyesters.
【0002】[0002]
【従来の技術】2,6−ナフタレンジカルボン酸ジメチ
ルの原料となる2,6−ナフタレンジカルボン酸は、一
般に2−アシル−6−アルキルナフタレン、2,6−ジ
アルキルナフタレン又は2,6−ジアシルナフタレン
を、コバルト、マンガンおよび臭素化合物触媒の存在
下、酢酸溶媒中において分子状酸素で酸化して製造する
方法が知られている。 次に、2,6−ナフタレンジカ
ルボン酸ジメチルは、上記の如き2,6−ナフタレンジ
カルボン酸をメタノールでエステル化する方法で製造さ
れるが、2,6−ナフタレンジカルボン酸はメタノール
に難溶でありエステル化反応速度は極めて遅く、そのた
めエステル化触媒を用いて反応を速める種々の方法が提
案されている。例えば、特公昭49-174号には硫酸等の鉱
酸を用いる方法、特公昭55-33704号には銅、マンガン、
レニウム、銅の酸化物、クロムの酸化物などを用いる方
法、特公昭58-1099 号には硫酸ベリリウム、硫酸ビスマ
ス、硫酸バナジル、チタン酸テトラーnーブチル、チタ
ン酸テトラーisoープロピルなどを用いる方法、特開
昭50-83360号には硫酸第二鉄、硫酸水銀、硫酸インジウ
ム、硫酸亜鉛などを用いる方法、特開昭50-83361号、特
開昭50-84553号および特開昭50-88058号にはモリブデン
の酸化物、硫化物、シアン化物、チオシアン化物、モリ
ブデン酸、リンモリブデン酸などのモリブデン化合物な
どを用いる方法、特開昭51ー 48641 号には塩基性酢酸ア
ルミニウム、塩化第一錫、二酸化テルル、タングストケ
イ酸などを用いる方法が提案されている。2. Description of the Related Art 2,6-Naphthalenedicarboxylic acid, which is a raw material for dimethyl 2,6-naphthalenedicarboxylic acid, generally comprises 2-acyl-6-alkylnaphthalene, 2,6-dialkylnaphthalene or 2,6-diacylnaphthalene. There is known a method for producing by oxidizing with molecular oxygen in an acetic acid solvent in the presence of a cobalt, manganese, and bromine compound catalyst. Next, dimethyl 2,6-naphthalenedicarboxylic acid is produced by a method of esterifying 2,6-naphthalenedicarboxylic acid with methanol as described above, but 2,6-naphthalenedicarboxylic acid is hardly soluble in methanol. Since the esterification reaction rate is extremely slow, various methods for accelerating the reaction using an esterification catalyst have been proposed. For example, Japanese Patent Publication No. 49-174, a method using a mineral acid such as sulfuric acid, Japanese Patent Publication No. 55-33704, copper, manganese,
Methods using rhenium, copper oxides, chromium oxides, etc., JP-B-58-1099 include methods using beryllium sulfate, bismuth sulfate, vanadyl sulfate, tetra-n-butyl titanate, tetra-iso-propyl titanate, etc. In Japanese Patent Laid-Open No. 50-83360, methods using ferric sulfate, mercury sulfate, indium sulfate, zinc sulfate, etc. are disclosed in JP-A-50-83361, JP-A-50-84553 and JP-A-50-88058. Is a method using a molybdenum compound such as molybdenum oxide, sulfide, cyanide, thiocyanide, molybdic acid, and phosphomolybdic acid. JP-A-51-48641 discloses basic aluminum acetate, stannous chloride, and dioxide. A method using tellurium, tungstosilicic acid, etc. has been proposed.
【0003】[0003]
【発明が解決しようとする問題点】しかしながらこれら
の公知の方法は、工業的な装置及び操作の観点からは必
ずしも満足されるものではなく、種々の問題点を有して
いる。例えば、硫酸等の鉱酸を用いる方法では、反応装
置の耐腐食性が要求されるため設備費が嵩み、その上、
ジメチルエーテルの副生を伴うためメタノールの損失も
大きい。 また、前述した各種金属や金属化合物を触媒
として用いる方法ではある程度エステル化反応は促進さ
れるが、先に述べた如き2,6−ナフタレンジカルボン
酸を原料とする場合には、工業的には満足される反応速
度、反応収率は得られない。 また、これらの金属化合
物触媒のうちチタン酸テトラーisoープロピル、チタ
ン酸テトラーnーブチル、リンモリブデン酸触媒は比較
的エステル化反応に有効なことが知られているが、本発
明者らの検討によれば、先に述べた如き2,6−ナフタ
レンジカルボン酸を原料とする場合には、やはり満足な
反応速度は得られず、その上反応器の内壁に不溶性の固
形物が付着し反応器を閉塞することなど、工業的な製造
方法としては不適当であることが判明した。However, these known methods are not always satisfactory from the industrial equipment and operation point of view, and have various problems. For example, in the method using a mineral acid such as sulfuric acid, the equipment cost is increased because the corrosion resistance of the reactor is required, and moreover,
The loss of methanol is large because it is accompanied by dimethyl ether as a byproduct. Further, although the esterification reaction is promoted to some extent by the method using the above-mentioned various metals or metal compounds as a catalyst, when the above-mentioned 2,6-naphthalenedicarboxylic acid is used as a raw material, it is industrially satisfactory. The obtained reaction rate and reaction yield cannot be obtained. Further, among these metal compound catalysts, tetra-iso-propyl titanate, tetra-n-butyl titanate, and phosphomolybdic acid catalyst are known to be relatively effective in the esterification reaction, but according to the studies by the present inventors. For example, when the above-mentioned 2,6-naphthalenedicarboxylic acid is used as a raw material, a satisfactory reaction rate cannot be obtained, and in addition, an insoluble solid substance adheres to the inner wall of the reactor to block the reactor. It was found that this is not suitable as an industrial manufacturing method.
【0004】[0004]
【問題を解決するための手段】そこで本発明者らは、エ
ステル化触媒を使用した場合について、実用化可能な方
法を開発すべく種々検討したところ、原料として使用す
る2,6−ナフタレンジカルボン酸の品質によって触媒
の活性及び閉塞物の量が大きく変化することを見いだし
た。 この原因について鋭意検討した結果、2,6−ナ
フタレンジカルボン酸中に含まれるコバルトやマンガン
がエステル化触媒の活性及び閉塞物の生成に大きく影響
していること、またこの閉塞物は2,6−ナフタレンジ
カルボン酸のコバルト塩及びマンガン塩であることが判
り、コバルト、マンガン含有量を制御した2,6−ナフ
タレンジカルボン酸を原料として使用することによりエ
ステル化触媒は有効に働くこと、および閉塞物の生成量
も著しく減少できること、その結果、高収率で2,6−
ナフタレンジカルボン酸ジメチルが得られることなどが
判明し、本発明を完成させるに至った。即ち本発明は、
2,6−ナフタレンジカルボン酸とメタノールを反応さ
せて2,6− ナフタレンジカルボン酸ジメチルを製造
するに際して、原料としてコバルト含有量が200pp
m以下およびマンガン含有量が200ppm以下の2,
6−ナフタレンジカルボン酸を使用することを特徴とす
る2,6−ナフタレンジカルボン酸ジメチルの製造方法
を提供するものである。[Means for Solving the Problem] Then, the inventors of the present invention have conducted various studies to develop a method that can be put to practical use in the case of using an esterification catalyst, and found that 2,6-naphthalenedicarboxylic acid used as a raw material. It was found that the activity of the catalyst and the amount of clogging vary greatly depending on the quality of the. As a result of diligent examination of the cause, it was found that cobalt and manganese contained in 2,6-naphthalenedicarboxylic acid had a great influence on the activity of the esterification catalyst and the formation of clogging substances, and the clogging substances were 2,6- It was found to be a cobalt salt and a manganese salt of naphthalenedicarboxylic acid, and the esterification catalyst worked effectively by using 2,6-naphthalenedicarboxylic acid whose cobalt and manganese contents were controlled as a raw material, and The production amount can be remarkably reduced, resulting in high yield of 2,6-
It was found that dimethyl naphthalenedicarboxylate was obtained, and the present invention was completed. That is, the present invention is
When 2,6-naphthalenedicarboxylic acid and methanol are reacted to produce dimethyl 2,6-naphthalenedicarboxylic acid, the content of cobalt is 200 pp as a raw material.
m or less and manganese content of 200 ppm or less 2,
The present invention provides a method for producing dimethyl 2,6-naphthalenedicarboxylic acid, which comprises using 6-naphthalenedicarboxylic acid.
【0005】本発明において原料に用いる2,6−ナフ
タレンジカルボン酸は、コバルト、マンガンの含有量が
それぞれ200ppm以下であれば如何なる方法により
製造または精製されたものでもよい。前述の如く、コバ
ルト、マンガン触媒を使用し、2−アシル−6−アルキ
ルナフタレン、2,6−ジアルキルナフタレンあるいは
2,6−ジアシルナフタレンを液相酸化することにより
製造される2,6−ナフタレンジカルボン酸の場合に
は、通常数千ppmのコバルト、マンガンを含有してい
る。 そのままの状態で原料として用いた場合には、エ
ステル化触媒の活性を損なうのみならず、反応器内に不
溶性の固形物が多く生成し、工業的な2,6−ナフタレ
ンジカルボン酸ジメチルの製造にはならないことは既に
述べた通りである。本発明方法では、コバルト、マンガ
ンがそれぞれ200ppm以下の2,6−ナフタレンジ
カルボン酸を原料とすることが必須要件となる。本発明
の要件を満たすためには、通常の方法で製造され分離回
収された2,6−ナフタレンジカルボン酸を、水、酢
酸、メタノールあるいはこれらの混合溶媒で更に洗浄す
ることが有効であり、特に水で洗浄するのが洗浄効果の
点、安全性および経済性の面からより有利である。The 2,6-naphthalenedicarboxylic acid used as a raw material in the present invention may be produced or purified by any method as long as the contents of cobalt and manganese are each 200 ppm or less. As described above, 2,6-naphthalenedicarboxylic acid produced by liquid phase oxidation of 2-acyl-6-alkylnaphthalene, 2,6-dialkylnaphthalene or 2,6-diacylnaphthalene using a cobalt or manganese catalyst. In the case of acid, it usually contains several thousands ppm of cobalt and manganese. When used as a raw material as it is, it not only impairs the activity of the esterification catalyst, but also produces a large amount of insoluble solids in the reactor, which is suitable for industrial production of dimethyl 2,6-naphthalenedicarboxylate. That is not the case as already mentioned. In the method of the present invention, it is an essential requirement to use 2,6-naphthalenedicarboxylic acid containing cobalt and manganese of 200 ppm or less as raw materials. In order to meet the requirements of the present invention, it is effective to further wash the 2,6-naphthalenedicarboxylic acid produced and separated and recovered by a usual method with water, acetic acid, methanol or a mixed solvent thereof, and particularly, Washing with water is more advantageous in terms of washing effect, safety and economy.
【0006】本発明において、エステル化触媒は公知の
触媒が使用できるが、特にチタン酸テトラーnーブチ
ル、チタン酸テトラーisoープロピルあるいはリンモ
リブデン酸などを用いる際に本発明の効果が顕著に表れ
る。これらエステル化触媒の使用量は、2,6−ナフタ
レンジカルボン酸に対して0.01〜5重量%、好まし
くは0.03〜2重量%である。 0.01重量%より
も少ないとエステル化反応速度は小さく好ましくない。
また、5重量%より多くしても反応速度や反応収率は
あまり向上しないので経済的ではない。In the present invention, a known catalyst can be used as the esterification catalyst, and the effect of the present invention is particularly remarkable when tetra-n-butyl titanate, tetra-iso-propyl titanate or phosphomolybdic acid is used. The amount of these esterification catalysts used is 0.01 to 5% by weight, preferably 0.03 to 2% by weight, based on 2,6-naphthalenedicarboxylic acid. If the amount is less than 0.01% by weight, the esterification reaction rate will be low, which is not preferable.
Further, even if it exceeds 5% by weight, the reaction rate and the reaction yield are not improved so much, so that it is not economical.
【0007】エステル化反応に使用するメタノールの量
は、2,6−ナフタレンジカルボン酸に対する重量比で
1〜10倍、好ましくは4〜6倍である。 メタノール
の使用量が少なすぎるとエステル化反応は小さくなるた
め好ましくない。 また、必要以上に多くしても反応速
度や反応収率はあまり向上しなく、また未反応メタノ−
ルの回収量が多くなり経済的に不利である。エステル化
温度は、通常200℃〜350℃、好ましくは220〜
280℃である。 200℃以下の温度ではエステル化
の速度は小さくなり好ましくない。また350℃より高
い温度では重合物やジメチルエーテルの副生が多くなり
収率が低下し好ましくない。反応時間は、触媒量や反応
温度によって変化するが、通常10分から5時間程度で
ある。 反応の方式は、回分式、半回分式、連続式い
ずれでもよい。The amount of methanol used in the esterification reaction is 1 to 10 times, preferably 4 to 6 times the weight ratio of 2,6-naphthalenedicarboxylic acid. If the amount of methanol used is too small, the esterification reaction becomes small, which is not preferable. In addition, the reaction rate and the reaction yield are not significantly improved even if the amount is increased more than necessary, and the unreacted methano-
It is economically disadvantageous because of the large amount of waste collected. The esterification temperature is usually 200 ° C to 350 ° C, preferably 220 ° C.
280 ° C. At a temperature of 200 ° C. or lower, the rate of esterification becomes low, which is not preferable. Further, at a temperature higher than 350 ° C., the amount of polymer and dimethyl ether by-produced increases and the yield decreases, which is not preferable. The reaction time varies depending on the amount of catalyst and the reaction temperature, but is usually about 10 minutes to 5 hours. The reaction system may be a batch system, a semi-batch system, or a continuous system.
【0008】[0008]
【発明の効果】本発明によれば、エステル化の困難な
2,6−ナフタレンジカルボン酸をメタノールと反応さ
せて2,6−ナフタレンジカルボン酸ジメチルを製造す
るに当たり、原料としてコバルト、マンガン含有量の少
ない2,6−ナフタレンジカルボン酸を用いることによ
って、高い反応速度と収率が達成できるものであり、そ
の工業的意義は極めて大きい。According to the present invention, when 2,6-naphthalenedicarboxylic acid, which is difficult to be esterified, is reacted with methanol to produce dimethyl 2,6-naphthalenedicarboxylic acid, the raw materials containing cobalt and manganese are used. By using a small amount of 2,6-naphthalenedicarboxylic acid, a high reaction rate and a high yield can be achieved, and its industrial significance is extremely large.
【0009】[0009]
【実施例】次に、本発明について実施例及び比較例によ
り更に具体的に説明するが、本発明はこれらの実施例に
より制限されるものではない。比較例1 内容100mlのsus−316製反応器に、コバルトを
2530ppm 及びマンガンを3810ppm を含有する原
料2,6−ナフタレンジカルボン酸6.0g、メタノー
ル36.0g、チタン酸テトラーiso−プロピル触媒
を2,6−ナフタレンジカルボン酸に対して0.5重量
%を仕込み、反応温度230℃で1時間振盪しながら反
応を行った。反応終了後の反応器の内壁には多量の固形
物が付着していた。 反応器より内容物をジメチルホル
ムアミド中に取り出し溶解した後、ガスクロマトグラフ
により分析を行った。 その結果、2,6−ナフタレン
ジカルボン酸ジメチルの収率は21.5モル%であっ
た。EXAMPLES Next, the present invention will be explained more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. Comparative Example 1 In a 100 ml reactor made of sus-316, raw material 2,6-naphthalenedicarboxylic acid 6.0 g, methanol 36.0 g, and tetra-iso-propyl titanate catalyst 2 containing 2,530 ppm of cobalt and 3,810 ppm of manganese were used. 0.5% by weight relative to 6,6-naphthalenedicarboxylic acid was charged, and the reaction was carried out at a reaction temperature of 230 ° C. for 1 hour while shaking. After the reaction was completed, a large amount of solid matter was attached to the inner wall of the reactor. The content was taken out from the reactor into dimethylformamide, dissolved and then analyzed by gas chromatography. As a result, the yield of dimethyl 2,6-naphthalenedicarboxylate was 21.5 mol%.
【0010】比較例2 コバルト480ppm およびマンガン2500ppm を含有
する原料2,6−ナフタレンジカルボン酸を使用した以
外は、比較例1と同様に反応を行った。その結果、比較
例1と同様反応器の内壁に多くの固形物の付着が認めら
れ、また2,6−ナフタレンジカルボン酸ジメチルの収
率は27.1モル%であった。 Comparative Example 2 The reaction was carried out in the same manner as in Comparative Example 1 except that the starting material 2,6-naphthalenedicarboxylic acid containing 480 ppm of cobalt and 2500 ppm of manganese was used. As a result, as in Comparative Example 1, a large amount of solid matter was observed to be attached to the inner wall of the reactor, and the yield of dimethyl 2,6-naphthalenedicarboxylate was 27.1 mol%.
【0011】比較例3 触媒としてチタン酸テトラーn−ブチルを2,6−ナフ
タレンジカルボン酸に対して1.0重量%を使用した以
外は、比較例1と同様に反応を行った。その結果、比較
例1と同様反応器の内壁に多くの固形物の付着が認めら
れ、また2,6−ナフタレンジカルボン酸ジメチルの収
率は33.2モル%であった。 Comparative Example 3 The reaction was carried out in the same manner as in Comparative Example 1 except that tetra-n-butyl titanate was used as the catalyst in an amount of 1.0% by weight based on 2,6-naphthalenedicarboxylic acid. As a result, as in Comparative Example 1, a lot of solids were found to be attached to the inner wall of the reactor, and the yield of dimethyl 2,6-naphthalenedicarboxylate was 33.2 mol%.
【0012】比較例4 触媒としてリンモリブデン酸を2,6−ナフタレンジカ
ルボン酸に対して0.1重量%を使用し、反応時間を3
0分とした以外は、比較例1と同様に反応を行った。
その結果、比較例1と同様反応器の内壁に多くの固形物
の付着が認められ、また2,6−ナフ タレンジカルボ
ン酸ジメチルの収率は83.5モル%であった。 Comparative Example 4 Phosphomolybdic acid was used as a catalyst in an amount of 0.1% by weight based on 2,6-naphthalenedicarboxylic acid, and the reaction time was 3 times.
The reaction was performed in the same manner as in Comparative Example 1 except that the time was 0 minutes.
As a result, as in Comparative Example 1, a large amount of solid matter was observed to be attached to the inner wall of the reactor, and the yield of dimethyl 2,6-naphthalenedicarboxylate was 83.5 mol%.
【0013】実施例1 比較例1で用いたと同じ2,6−ナフタレンジカルボン
酸を10倍量の水で1時間撹拌下にて洗浄した後、これ
を濾過し乾燥した。 得られた2,6−ナフタレンジカ
ルボン酸中のコバルト含有量は126ppm 、マンガン含
有量は148ppm となった。このコバルト、マンガン含
有量の少ない2,6−ナフタレンジカルボン酸を原料と
して比較例1と同様に反応を行った。その結果、反応器
の内壁には固形物の付着は認められず、2,6−ナフタ
レンジカルボン酸ジメチルの収率は95.1モル%であ
った。 Example 1 The same 2,6-naphthalenedicarboxylic acid used in Comparative Example 1 was washed with 10 times the amount of water for 1 hour under stirring, then filtered and dried. In the obtained 2,6-naphthalenedicarboxylic acid, the cobalt content was 126 ppm and the manganese content was 148 ppm. A reaction was carried out in the same manner as in Comparative Example 1 using 2,6-naphthalenedicarboxylic acid having a small content of cobalt and manganese as a raw material. As a result, no solid matter was observed on the inner wall of the reactor, and the yield of dimethyl 2,6-naphthalenedicarboxylate was 95.1 mol%.
【0014】実施例2 実施例1で使用したコバルト、マンガン含有量の少ない
2,6−ナフタレンジカルボン酸を使用した以外は、比
較例3と同様に反応を行った。その結果、反応器の内壁
には固形物の付着は認められず、2,6−ナフタレンジ
カルボン酸ジメチルの収率は94.8モル%であった。 Example 2 A reaction was carried out in the same manner as in Comparative Example 3 except that the 2,6-naphthalenedicarboxylic acid having a low cobalt and manganese content used in Example 1 was used. As a result, no solid matter was found on the inner wall of the reactor, and the yield of dimethyl 2,6-naphthalenedicarboxylate was 94.8 mol%.
【0015】実施例3 実施例1で使用したコバルト、マンガン含有量の少ない
2,6−ナフタレンジカルボン酸を使用した以外は、比
較例4と同様に反応を行った。その結果、反応器の内壁
には固 形物の付着は認められず、2,6−ナフタレン
ジカルボン酸ジメチルの収率は95.0モル%であっ
た。 Example 3 A reaction was carried out in the same manner as in Comparative Example 4 except that 2,6-naphthalenedicarboxylic acid having a small content of cobalt and manganese used in Example 1 was used. As a result, solid matter was not attached to the inner wall of the reactor, and the yield of dimethyl 2,6-naphthalenedicarboxylate was 95.0 mol%.
【0016】実施例4 比較例1で使用したコバルト2530ppm及びマンガ
ン3810ppmを含有する2,6−ナフタレンジカル
ボン酸を10倍量の重量比で1:1の水と酢酸の混合溶
媒で1時間撹拌下洗浄した後、これを濾過し乾燥した。
得られた2,6−ナフタレンジカルボン酸中のコバルト
含有量は155ppm 、マンガン含有量は173ppm とな
った。このコバルト、マンガン含有量の少ない2,6−
ナフタレンジカルボン酸を原料として実施例1と同様に
反応を行った。その結果、反応器の内壁には固形物の付
着は認められず、2,6−ナフタレンジカルボン酸ジメ
チルの収率は94.7モル%であった。 Example 4 2,6-naphthalenedicarboxylic acid containing 2530 ppm of cobalt and 3810 ppm of manganese used in Comparative Example 1 was stirred under a weight ratio of 10 times with a mixed solvent of water and acetic acid of 1: 1 for 1 hour. After washing, it was filtered and dried.
The cobalt content in the obtained 2,6-naphthalenedicarboxylic acid was 155 ppm and the manganese content was 173 ppm. 2,6-Low content of cobalt and manganese
A reaction was carried out in the same manner as in Example 1 using naphthalenedicarboxylic acid as a raw material. As a result, no solid matter was observed on the inner wall of the reactor, and the yield of dimethyl 2,6-naphthalenedicarboxylate was 94.7 mol%.
Claims (3)
ールを反応させて2,6−ナフタレンジカルボン酸ジメ
チルを製造するに際し、原料としてコバルト含有量が2
00ppm以下及びマンガン含有量が200ppm以下
の2,6−ナフタレンジカルボン酸を使用することを特
徴とする2,6−ナフタレンジカルボン酸ジメチルの製
造方法。1. When a dimethyl 2,6-naphthalenedicarboxylic acid is produced by reacting 2,6-naphthalenedicarboxylic acid with methanol, a cobalt content of 2 is used as a raw material.
A method for producing dimethyl 2,6-naphthalenedicarboxylic acid, which comprises using 2,6-naphthalenedicarboxylic acid having a content of 00 ppm or less and a manganese content of 200 ppm or less.
ル、チタン酸テトラーisoープロピル、及びリンモリ
ブデン酸から選ばれた一種以上を使用する請求項1項記
載の方法。2. The method according to claim 1, wherein at least one selected from tetra-n-butyl titanate, tetra-iso-propyl titanate, and phosphomolybdic acid is used as the catalyst.
で行う請求項1項記載の方法。3. The method according to claim 1, wherein the esterification reaction is carried out at a temperature of 200 to 350 ° C.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP5249522A JP3024459B2 (en) | 1993-10-05 | 1993-10-05 | Process for producing dimethyl 2,6-naphthalenedicarboxylate |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP5249522A JP3024459B2 (en) | 1993-10-05 | 1993-10-05 | Process for producing dimethyl 2,6-naphthalenedicarboxylate |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH07101906A true JPH07101906A (en) | 1995-04-18 |
JP3024459B2 JP3024459B2 (en) | 2000-03-21 |
Family
ID=17194233
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP5249522A Expired - Lifetime JP3024459B2 (en) | 1993-10-05 | 1993-10-05 | Process for producing dimethyl 2,6-naphthalenedicarboxylate |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP3024459B2 (en) |
-
1993
- 1993-10-05 JP JP5249522A patent/JP3024459B2/en not_active Expired - Lifetime
Also Published As
Publication number | Publication date |
---|---|
JP3024459B2 (en) | 2000-03-21 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP0267556B1 (en) | Process for production of methacrolein and methacrylic acid | |
US5081290A (en) | Process for making aromatic polycarboxylic acids and oxidation catalyst system | |
US4346232A (en) | Process for producing aromatic polycarboxylic acid | |
JP2719998B2 (en) | A novel catalyst system and its application to oxydehydrogenation of saturated carboxylic acids and oxidation of aldehydes to acids | |
US5208371A (en) | Process for production of methacrolein and methacrylic acid | |
EP0450621A2 (en) | Process for the preparation of high-purity 2,6 naphthalenedicarboxylic acid esters | |
JP4182237B2 (en) | Catalyst for gas-phase catalytic oxidation reaction of isobutane and method for producing alkene and / or oxygen-containing compound using the same | |
JP4788022B2 (en) | Process for producing aromatic polycarboxylic acid | |
JPH07101906A (en) | Production of dimethyl 2,6-naphthalenedicarboxylate | |
JPH0567132B2 (en) | ||
JP3039599B2 (en) | Process for producing dimethyl 4,4'-biphenyldicarboxylate | |
JP2894415B2 (en) | Process for producing dimethyl 2,6-naphthalenedicarboxylate | |
JP3027162B2 (en) | Method for producing biphenylcarboxylic acid | |
JPS5949214B2 (en) | Process for producing unsaturated carboxylic acids or their esters | |
US20020133043A1 (en) | Method for production of oxygen-containing aromatic compound | |
JP2985921B2 (en) | Process for producing dimethyl 2,6-naphthalenedicarboxylate | |
EP0041778B2 (en) | Oxidation of meta- or para-xylene to iso- or tere-phthalic acid | |
JPH06211744A (en) | Production of high-purity dimethyl 4,4'-biphenyldicarboxylate | |
JP3859397B2 (en) | Catalyst for production of methacrolein and methacrylic acid | |
JP4352191B2 (en) | Production of pyromellitic acid | |
JP3726312B2 (en) | Method for producing methacrolein and / or methacrylic acid | |
JP2001122808A (en) | Method for producing aromatic compound | |
EP1205462A1 (en) | Method for production of oxygen-containing aromatic compound | |
DE2804156C2 (en) | Process for the production of terephthalic acid | |
JP2001131135A (en) | Method for producing acrylonitrile |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080121 Year of fee payment: 8 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090121 Year of fee payment: 9 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100121 Year of fee payment: 10 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100121 Year of fee payment: 10 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110121 Year of fee payment: 11 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120121 Year of fee payment: 12 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120121 Year of fee payment: 12 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130121 Year of fee payment: 13 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20140121 Year of fee payment: 14 |
|
EXPY | Cancellation because of completion of term |