【発明の詳細な説明】本発明は、粗テレフタル酸の精製法に関するものであり
、詳しくはｐ−ジアルキルベンゼンの液相空気酸化によ
り得られた粗テレフタル酸の接触水添による高純度テレ
フタル酸の製造法の改良に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for purifying crude terephthalic acid, and more specifically to a method for purifying crude terephthalic acid by catalytic hydrogenation of crude terephthalic acid obtained by liquid phase air oxidation of p-dialkylbenzene. Concerning improvements in manufacturing methods.
テレフタル酸とジオールの重縮合によるポリエステルの
製造は、近年高純度テレフタル酸製造技術の発達に伴い
、ジメチルテレフタレートによるエステル交換法に代わ
つてテレフタノ１の直接重合法が主流を占めるようにな
つてきている。In recent years, with the development of high-purity terephthalic acid production technology, direct polymerization of terephthalic acid 1 has become mainstream, replacing the transesterification method using dimethyl terephthalate, in the production of polyesters through the polycondensation of terephthalic acid and diols. .
当然のことながら、繊維あるいはフィルム原料とするポ
リエステルの直接重合用テレフタル酸には高純度が要求
される。ｐ−ジアルキルベンゼンの液相空気酸化によつ
て得られる粗テレフタル酸には、ポリエステルに好まし
くない影響を及ぼす４−カルボキシベンズアルデヒド（
以下４ＣＢＡと略記する）および着色性有機物などの有
機不純物が含有されているので、このような粗テレフタ
ル酸を直接重合法に適する高純度テレフタル酸とするに
は精製を必要とする。Naturally, high purity is required for terephthalic acid for direct polymerization of polyester used as a raw material for fibers or films. Crude terephthalic acid obtained by liquid phase air oxidation of p-dialkylbenzene contains 4-carboxybenzaldehyde (4-carboxybenzaldehyde), which has an undesirable effect on polyester.
Since such crude terephthalic acid contains organic impurities such as 4CBA (hereinafter abbreviated as 4CBA) and colored organic substances, purification is required to convert such crude terephthalic acid into high-purity terephthalic acid suitable for direct polymerization.
このような粗テレフタノ者の精製法の一つとして、粗テ
レフタル酸水溶液を高温、高圧下に於いて水添触媒の存
在下に水素で処理し、かつ、処理された水溶液から固体
テレフタル酸を回収する方法が提案されている（特公昭
４１−１６８６０号公報参照）。しかしこの方法にした
がつて直接重合法に適した高純度テレフタル酸を製造し
ようとすれば、水添工程に於けるｐ−トルイル酸の生成
は不可避であり、このｐ−トルイル酸のテレフタル酸へ
の混入を防ぐために工業操作が複雑となり、上記方法は
必ずしも満足し得る方法とはいえない。本発明者らは、
上記方法のかかる欠陥を改良すべく水添精製方法につい
て鋭意研究を重ねた結果、上記の水添精製方法において
水添処理を前半と後半とに分けて行ない、かつ前半の水
添工程に於いて限られた量の水素の存在下に粗テレフタ
ル酸水溶液を水添処理し、次いで更に水素を追加して水
添処理することによつて、これらの水素を一度に使用し
て水添処理する場合よりも、実質的にｐ−トルイル酸が
減少すること、さらにかくして得られたテレフタル酸は
白色度のすぐれたポリエステルを与えることを見出し、
本発明に到達した。One method for purifying such crude terephthalic acid is to treat an aqueous solution of crude terephthalic acid with hydrogen in the presence of a hydrogenation catalyst at high temperature and pressure, and to recover solid terephthalic acid from the treated aqueous solution. A method has been proposed (see Japanese Patent Publication No. 41-16860). However, if one attempts to produce high-purity terephthalic acid suitable for direct polymerization using this method, the production of p-toluic acid in the hydrogenation process is unavoidable, and this p-toluic acid is converted into terephthalic acid. In order to prevent contamination, industrial operations become complicated, and the above method cannot necessarily be said to be a satisfactory method. The inventors
As a result of intensive research on hydrogenation purification methods to improve this defect in the above method, we have divided the hydrogenation treatment into the first half and the second half in the above hydrogenation purification method, and in the first half hydrogenation process. When a crude terephthalic acid aqueous solution is hydrogenated in the presence of a limited amount of hydrogen, and then further hydrogen is added and hydrogenated, these hydrogens are used all at once. found that p-toluic acid was substantially reduced, and that the terephthalic acid thus obtained gave a polyester with excellent whiteness,
We have arrived at the present invention.
すなわち、本発明の方法は、ｐージアルキルベンゼンの
液相空気酸化によつて得られた粗テレフタル酸水溶液を
高められた温度および圧力に於いて水素と共に第８族貴
金属触媒と接触させ、次いで冷却して固体テレフタル酸
を回収することより成るテレフタ匹酸精製法において水
添処理工程における全水素使用量を粗テレフタル酸水溶
液中に含まれる４−カルボキシベンズアルデヒドの２．
０〜２０倍モルとし、且つ水添処理工程の前半（全工程
の１／３〜２／３）を該４−カルボキシベンズアルデヒ
ドの０．３５〜１．９５倍モルの水素の存在下に行なう
ことを特徴とするテレフタ元酸の精製法である。次に本
発明の態様について詳細に説明する。That is, the process of the present invention involves contacting a crude aqueous terephthalic acid solution obtained by liquid phase air oxidation of p-dialkylbenzene with a Group 8 precious metal catalyst with hydrogen at elevated temperature and pressure, followed by cooling. In the terephthalic acid purification method, which consists of recovering solid terephthalic acid, the total amount of hydrogen used in the hydrogenation step is calculated as 2.0% of the total amount of hydrogen used in the hydrogenation process.
0 to 20 times the mole of hydrogen, and the first half of the hydrogenation process (1/3 to 2/3 of the entire process) is carried out in the presence of 0.35 to 1.95 times the mole of hydrogen of the 4-carboxybenzaldehyde. This is a method for purifying terephthalic acid, which is characterized by the following. Next, aspects of the present invention will be explained in detail.
本発明の方法は、ｐージアルキルベンゼンの液相空気酸
化によつて得られる粗テレフタル酸の精製に適用できる
。液相酸化によつて得られる粗テレフタル酸は４ＣＢＡ
および着色性有機物を含有しており、粗テレフタル酸の
品質は代表的な不純物である４ＣＢＡ含量で示され一般
に粗テレフタル酸は４ＣＢＡを５００〜５０００ｐｐｍ
程度含有している。かかる粗テレフタル酸を前記公知の
方法にしたがい直接重合用高純度テレフタル酸を製造し
ようとすれば、水添処理によるｐ−トルイル酸の生成を
避けることができない。すなわち白色度．にすぐれたポ
リエステルを与える高純度テレフタル酸にまで精製する
には通常水添処理に際し、粗テレフタル酸に含有される
４ＣＢＡ１モルに対して２モル以上の水素を必要とし、
かつ大部分の４ＣＢＡはｐ−トルイル酸に還元されるの
でｐ−トルイル酸の生成り粗テレフタル酸中の４ＣＢＡ
に比例して増加する。しかしながら、４ＣＢＡ１モルに
対して２モル以上の水素を使用しても、本発明の方法に
したがつて使用する水素を分割して水添処理を行なえば
、同じ量の水素で一度に水添処理する場合に比べｐ−ト
ルイル酸の生成をはるかに少く抑えることができるので
、実質的にｐ−トルイル酸含量の低い精製テレフタル酸
とすることができる。The method of the invention is applicable to the purification of crude terephthalic acid obtained by liquid phase air oxidation of p-dialkylbenzene. Crude terephthalic acid obtained by liquid phase oxidation is 4CBA
The quality of crude terephthalic acid is indicated by the content of 4CBA, which is a typical impurity. Generally, crude terephthalic acid contains 4CBA at a concentration of 500 to 5000 ppm.
Contains some degree. If it is attempted to produce high-purity terephthalic acid for direct polymerization from such crude terephthalic acid according to the above-mentioned known method, the production of p-toluic acid due to hydrogenation cannot be avoided. In other words, whiteness. In order to purify high-purity terephthalic acid that yields a polyester with excellent properties, 2 moles or more of hydrogen is usually required per mole of 4CBA contained in crude terephthalic acid during hydrogenation treatment.
Since most of 4CBA is reduced to p-toluic acid, p-toluic acid is produced and 4CBA in crude terephthalic acid is reduced to p-toluic acid.
increases in proportion to However, even if 2 moles or more of hydrogen is used per mole of 4CBA, if the hydrogen used is divided and hydrogenated according to the method of the present invention, the same amount of hydrogen can be used for hydrogenation at once. Since the production of p-toluic acid can be suppressed to a much lower level than in the case where p-toluic acid is produced, purified terephthalic acid having a substantially low p-toluic acid content can be obtained.
水添■程の前半で存在させる水素量は粗テレフタル酸に
含有される４ＣＢＡに対して０．３５〜１．９５倍モル
とすることが必要であり、特に０．４〜１．９倍モルの
範囲に調節するのが望ましい。上記の範囲未満に水素量
を減らしすぎると触媒活性の急速な低下を招き、触媒寿
命が短くなるために経済的にきわめて不利となる。加え
て、触媒活性の低下は精製テレフタル酸白度の劣化を来
たすので、この場合には得られるテレフタル酸の白度を
維持するために続く水添工程の水素量を増さねばならな
くなり、結果的にはｐ−トルイル酸は減少しなくなる。
また逆に水素量を増しすぎてもｐ−トルイル酸の生成が
ふえて本発明の効尿は認められなくなる。本発明の水添
処理工程における全水素使用量は、粗テレフタ側酸の品
質および触媒活性に応じて、粗テレフタル酸中の４ＣＢ
Ａに対して２．０〜２０倍モルの範囲で適当に選ぶこと
ができ、工程の前半で存在させた水素を除いた残部の水
素を更に反応系に追加供給して工程の後半を行なう。本
発明の方法は、連続法あるいは回分法の何れにも適用で
きるが、特に連続法に適する。さらに本発明の水添処理
は１基の反応器あるいは複数基の反応器に於いて実施し
得る。連続法で１基の反応器を用いて水添処理を行なう
場合には、触媒層を区分し、区分された触媒層の入口部
から前記の比率に応じた量の水素を供給すればよ（・。
反応器が１基あるいは複数基の何れにしても、充填する
触媒量の配分は前半の水添工程と次に続く後半の水添工
程に対する割合が１：２〜２：１の範囲に任意に選ぶこ
とができる。なお、ここで複数基とは２基とは限らず、
例えば後半の水添工程に２基を用い合計３基で水添を行
う場合も含まれる。各々の水添処理に於ける滞留時間は
１〜６０分間の範囲であれば良い。本発明の方法に於サ
る第８族貴金属触媒としては公知の水添触媒が使用でき
る。The amount of hydrogen present in the first half of the hydrogenation step (2) needs to be 0.35 to 1.95 times the mole of 4CBA contained in the crude terephthalic acid, particularly 0.4 to 1.9 times the mole of 4CBA contained in the crude terephthalic acid. It is desirable to adjust it within the range of . If the amount of hydrogen is reduced too much below the above range, the catalyst activity will drop rapidly and the catalyst life will be shortened, which is extremely disadvantageous economically. In addition, a decrease in catalytic activity causes a deterioration in the whiteness of purified terephthalic acid, so in this case it is necessary to increase the amount of hydrogen in the subsequent hydrogenation step in order to maintain the whiteness of the obtained terephthalic acid. Specifically, p-toluic acid no longer decreases.
Conversely, if the amount of hydrogen is increased too much, the production of p-toluic acid will increase and the urinary effect of the present invention will not be observed. The total amount of hydrogen used in the hydrogenation process of the present invention depends on the quality and catalyst activity of the crude terephthalic acid.
The amount of hydrogen can be appropriately selected in the range of 2.0 to 20 times mole relative to A, and the remaining hydrogen after removing the hydrogen present in the first half of the process is further supplied to the reaction system for the second half of the process. The method of the present invention can be applied to either a continuous method or a batch method, but is particularly suitable for a continuous method. Furthermore, the hydrogenation process of the present invention can be carried out in one reactor or in multiple reactors. When carrying out hydrogenation treatment using one reactor in a continuous method, the catalyst bed can be divided and hydrogen can be supplied in an amount according to the above ratio from the inlet of the divided catalyst bed.・.
Regardless of whether there is one reactor or multiple reactors, the amount of catalyst charged can be arbitrarily distributed within the range of 1:2 to 2:1 between the first half hydrogenation step and the subsequent second half hydrogenation step. You can choose. Note that the term "multiple units" here does not necessarily mean two units.
For example, this also includes a case where two units are used in the latter hydrogenation step and hydrogenation is performed with a total of three units. The residence time in each hydrogenation treatment may be in the range of 1 to 60 minutes. As the Group 8 noble metal catalyst used in the method of the present invention, known hydrogenation catalysts can be used.
例えば、ルテニウム、ロジウム パラジウム、オスミウ
ム、イソジウム、白金あるいはこれらの金属酸化物から
選ばれた水添触媒が好ましい。これらの金属もしくは金
属酸化物はそのまま使用することもできるが、活性炭の
ごとき担体に担持された触媒が特に有効である。水添処
理の際の温度は２００〜３００℃の範囲、特に２５０〜
２８５℃の範囲が好ましい。For example, a hydrogenation catalyst selected from ruthenium, rhodium, palladium, osmium, isodium, platinum, or metal oxides thereof is preferred. Although these metals or metal oxides can be used as they are, catalysts supported on a carrier such as activated carbon are particularly effective. The temperature during hydrogenation treatment is in the range of 200 to 300℃, especially 250 to 300℃.
A range of 285°C is preferred.
水添工程の温度は前、後半によつて変えても、同一であ
つてもよいが、同一温度の方が工業的操作は容易となる
。次に本発明について、実施例に基づき、さらに具体的
に説明する。The temperature in the hydrogenation step may be different in the first and second half, or may be the same, but industrial operations are easier if the temperature is the same. Next, the present invention will be described in more detail based on Examples.
なお比較例および実施例に示している、テレフタル酸の
アルカリ溶液吸光度（０Ｄ３４０と略して示す）とは、
２．００ｙのテレフタル酸を２Ｎ一ＫＯＨ水溶液２５ｍ
１に溶解し、この溶液を長さ５？のセルに入れて３４０
ｍμで測定した値である。The alkaline solution absorbance of terephthalic acid (abbreviated as 0D340) shown in the comparative examples and examples is as follows:
2.00y of terephthalic acid in 25m of 2N-KOH aqueous solution
1 and add this solution to a length of 5? Put it in the cell of 340
This is a value measured in mμ.
また、ポリマー白度は、ポリエステルチップを日本電色
株式会社製Ｎ−Ｄ−１０１Ｄ型測色色差計で測定した外
観色であり、ハンタスケールｂ値で示した値である。テ
レフタル酸の４ＣＢＡ量は、テレフタル酸をアンモニア
緩衝液に溶解してポーラログラフ法で測定した値であり
、またテレフタル酸中のｐ−トルイル酸量は、テレフタ
ル酸を塩酸触媒存在下メタノールによりエステル化して
ガスクロマトグラフにかけ、同時にエステル化されたｐ
−トルイル酸メチル量を測定することにより求めたもの
である〜重量部および容量部の単位は、それぞれ、Ｋ９およびＮ
ｌに対応する。Moreover, polymer whiteness is the external appearance color of a polyester chip measured with a colorimeter ND-101D manufactured by Nippon Denshoku Co., Ltd., and is a value expressed as a Hunter scale b value. The amount of 4CBA in terephthalic acid is the value measured by polarographic method after dissolving terephthalic acid in an ammonia buffer, and the amount of p-toluic acid in terephthalic acid is the value measured by dissolving terephthalic acid in an ammonia buffer and measuring the amount of p-toluic acid in terephthalic acid by esterifying terephthalic acid with methanol in the presence of a hydrochloric acid catalyst. Gas chromatographed and simultaneously esterified p
- It was determined by measuring the amount of methyl toluate - The units of parts by weight and parts by volume are K9 and N, respectively.
Corresponds to l.
実施例１ｐ−キシレンの液相空気酸化によつて得られた粗テレフ
タル酸（４ＣＢＡ１５００ｐｐｍ，．ｐ−トルイル酸２
００ｐｐｍ含有、０Ｄ３４０１．００）３重量部と純水
１７重量部の割合でテレフタル酸スラリーとし、チタン
製耐圧容器にパラジウムを０．５重量％粒状活性炭に担
持させた０．５％Ｐｄ−活性炭触媒０．２重量部をそれ
ぞれ充填した２基の反応塔Ａ，ＢをＡ，Ｂの順に直列に
つなぎ、あらかじめスラリーを加熱して溶解させたテレ
フタル酸水溶液を毎時５重量部の割合で温度２７５℃、
圧力７０ｋｇ／ＣｄＧで通液すると共に、反応塔入口部
に設けた水素供給管から反応塔ＡおよびＢに対してそれ
ぞれ水素０．３０および０．９０容量部供給した。Example 1 Crude terephthalic acid obtained by liquid phase air oxidation of p-xylene (4CBA 1500 ppm, p-toluic acid 2
A 0.5% Pd-activated carbon catalyst containing 0.5% by weight of palladium on granular activated carbon was made into a terephthalic acid slurry at a ratio of 3 parts by weight of 0D3401.00) and 17 parts by weight of pure water and placed in a titanium pressure vessel. Two reaction towers A and B each filled with 0.2 parts by weight are connected in series in the order of A and B, and a terephthalic acid aqueous solution, which has been dissolved by heating the slurry in advance, is heated at a rate of 5 parts by weight per hour at a temperature of 275°C. ,
While flowing at a pressure of 70 kg/CdG, 0.30 and 0.90 parts by volume of hydrogen were supplied to reaction towers A and B, respectively, from a hydrogen supply pipe provided at the inlet of the reaction tower.
Ａ塔中に供給した水素の対４ＣＢＡモル比は１．７９で
あつた。 ゛次ぃで反応塔Ｂから流出してくるテ
レフタル酸水溶液をＡ過器を通して沢過した後、２００
℃の晶析槽で、次いで１００℃の晶析槽で冷却してテレ
フタル酸を２段偕で晶析させ、その後１００℃で分離し
て乾燥した後、高純度テレフタル酸を得た。The molar ratio of hydrogen supplied to column A to 4CBA was 1.79. Next, after filtering the terephthalic acid aqueous solution flowing out from reaction tower B through filter A,
Terephthalic acid was crystallized in two stages by cooling in a crystallizer at 100°C and then in a crystallizer at 100°C, and then separated and dried at 100°C to obtain high purity terephthalic acid.
２００重量部のテレフタル酸が通液処理された時点で得
られた精製テレフタル酸の性状およびこれから得られた
ポリエステルの白度を第１表に示した。Table 1 shows the properties of the purified terephthalic acid obtained when 200 parts by weight of terephthalic acid was passed through the solution and the whiteness of the polyester obtained therefrom.
なお、この精製テレフタル酸の重縮合は次のごとく行な
つた。The polycondensation of this purified terephthalic acid was carried out as follows.
まず、精製テレフタル酸４００重量部、エチレングリコ
ール２７０部およびトリエチルアミン０．１２重量部を
ステンレス製オートクレーブに仕込み、窒素ガスで置換
後、圧力２．５ｋ９／ＣｄＧ一定に保ち、２３０℃で生
成する水を連続的に系外に除去しながらエステル化反応
を行なつた。このエステル化生成物を重縮合反応器に移
し、酢酸亜鉛２水塩０．０９０重量部、三酸化アンチモ
ン０．０５０重量部を添加した後、昇温しながら徐々に
減圧し２２５〜２５５℃、５１ｔ７１ｔＨｇで３０分間
初期重縮合し、次いで２７３℃、０．１ｍＴ！ＬＨｇで
５０分間後期重縮合を行なつた。以下の例で得られるテ
レフタル酸についても全く同様の操作によりポリエステ
ルチップを得、これの白度を測定した。実施例２実施例１の反応塔ＡおよびＢへの水素供給量をそれぞれ
毎時０．１８および２．８２容量部とした以外は実施例
１と全く同じ方法で同じ品質の粗テレフタル酸を精製し
た。First, 400 parts by weight of purified terephthalic acid, 270 parts of ethylene glycol, and 0.12 parts by weight of triethylamine were charged into a stainless steel autoclave, and after purging with nitrogen gas, the pressure was kept constant at 2.5k9/CdG, and the water generated at 230°C was The esterification reaction was carried out while continuously removing it from the system. This esterification product was transferred to a polycondensation reactor, and after adding 0.090 parts by weight of zinc acetate dihydrate and 0.050 parts by weight of antimony trioxide, the pressure was gradually reduced while increasing the temperature to 225-255°C. Initial polycondensation was carried out at 51t71tHg for 30 minutes, then at 273°C and 0.1mT! Late polycondensation was carried out at LHg for 50 minutes. For the terephthalic acid obtained in the following examples, polyester chips were obtained in exactly the same manner, and the whiteness of the chips was measured. Example 2 Crude terephthalic acid of the same quality was purified in exactly the same manner as in Example 1, except that the amount of hydrogen supplied to reaction towers A and B in Example 1 was 0.18 and 2.82 parts by volume per hour, respectively. .
最初の工程の水素の対４ＣＢＡモル比は１．０７であつ
た。テレフタル酸８００重量部処理時で第１表に示した
性状のテレフタル酸を得た。The molar ratio of hydrogen to 4CBA in the first step was 1.07. When treated with 800 parts by weight of terephthalic acid, terephthalic acid having the properties shown in Table 1 was obtained.
比較例１実施例１に示した同じ品質の粗テレフ！．ル酸を用い、
カリＡ，Ｂ二つの反応塔からなる同じ装置に於いて、実
施例１ではＡ，Ｂ二つの反応塔に分けた水素の合計量毎
時１．２容量部の水素を反Ｌ塔（４）から供給した以外
＆ζ実施例１と全く同じ方法で処理した。Comparative Example 1 Crude teref of the same quality as shown in Example 1! ．． using luic acid,
In Example 1, in the same apparatus consisting of two reaction towers A and B, the total amount of hydrogen divided into two reaction towers A and B was 1.2 parts by volume per hour from the anti-L tower (4). The process was carried out in exactly the same manner as in Example 1, except for supplying &ζ.
粗テレフタル酸２．００重量部処理した時点９結果を第
１表に示した。この場合水添工程の当初から多量の水素
が存在しているため、ｐ−トルイル酸の生成量も多く、
又ポリエステル白度も悪くなつている。Table 1 shows the results obtained at time 9 when 2.00 parts by weight of crude terephthalic acid was treated. In this case, since a large amount of hydrogen is present from the beginning of the hydrogenation process, a large amount of p-toluic acid is produced.
Also, the whiteness of polyester is getting worse.
比較例２反応塔ＡおよびＢに供給する水素量を、それぞれ、０．
０５容量部および１．１５容量部として、最初の水添工
程の水素を水添処理に用いる水素量の４％に変えた以外
は、実施例１と全く同じ方法で同じ素状の粗テレフタ四
陵を処理した。Comparative Example 2 The amount of hydrogen supplied to reaction towers A and B was set to 0.
05 parts by volume and 1.15 parts by volume, crude terephthalate in the same raw form was prepared in the same manner as in Example 1, except that the hydrogen in the first hydrogenation step was changed to 4% of the amount of hydrogen used in the hydrogenation treatment. Treated the mausoleum.
この場合、粗テレフタル酸２００重量部処理した時点の
結果を第１表に示した。なお、この場合ｐ−トルイル酸
の生成量は比較例１に比べ減少しているものの実施例１
、２に比べ著しく増加し、又ポリエステル白度は比較例
１よりも更に劣つている。In this case, the results obtained when 200 parts by weight of crude terephthalic acid were treated are shown in Table 1. In this case, although the amount of p-toluic acid produced was reduced compared to Comparative Example 1, Example 1
, 2, and the polyester whiteness was even worse than Comparative Example 1.
これは水添工程の前半を水素の少ない状態で行なうこと
の効果はある程度得られるものの、触媒の活性低下が著
しく、前半の水添が不充分な状態で後半の水素の多い状
態での水添工程に移る故であると考えられる。Although the effect of performing the first half of the hydrogenation process in a low hydrogen state can be obtained to some extent, the activity of the catalyst is significantly reduced, and hydrogenation in the second half with a high hydrogen content is insufficient. This is thought to be due to the shift to the process.
実施例３反応器内の触媒充填層を入口から１：２に分割する仕切
板を設け、かつ、入口部および仕切部に２本の水素供給
管を有する反応器に０．５％Ｐｄ−活性炭触媒０．３重
量部充填した反応塔に、ｐ−キシレンから得られた粗テ
レフタル酸（４ＣＢＡ３０２０ｐｐｍ，．ｐ−トルィノ
ｑ唆４０５ｐｐｍ１０Ｄ３４０１．５）１重量部、純水
４重量部からなるスラリーを加熱溶解した後毎時５重量
部の割合で通液すると共に、反応塔の入口部および仕切
部の水素供給管から、それぞれ、毎時０．３および１．
７容量部の割合で水素を供給した。Example 3 0.5% Pd-activated carbon was installed in a reactor that was equipped with a partition plate that divided the catalyst packed bed in the reactor 1:2 from the inlet and had two hydrogen supply pipes at the inlet and the partition. In a reaction tower filled with 0.3 parts by weight of catalyst, a slurry consisting of 1 part by weight of crude terephthalic acid obtained from p-xylene (4CBA3020ppm, .p-toluinoq 405ppm 10D3401.5) and 4 parts by weight of pure water was dissolved by heating. After that, hydrogen is passed at a rate of 5 parts by weight per hour, and 0.3 parts per hour and 1.0 parts per hour are supplied from the hydrogen supply pipes at the inlet and partition of the reaction tower, respectively.
Hydrogen was supplied at a rate of 7 parts by volume.
この場合の入口部の水素の対４ＣＢＡモル比は０．６７
であつた。また、温度および圧力は２８０℃および７３
ｋｇ／ＣｄＧであつた。この反応塔から流出したテレフ
タル酸水溶液を実施例１と同様に処理して高純度テレフ
タル酸を得た。In this case, the molar ratio of hydrogen to 4CBA at the inlet is 0.67
It was hot. Also, the temperature and pressure are 280℃ and 73℃.
kg/CdG. The aqueous terephthalic acid solution flowing out from this reaction tower was treated in the same manner as in Example 1 to obtain high purity terephthalic acid.
テレフタル酸処理量８００重量部における精製テレフタ
ル酸およびこれから得られたポリエステルの性状は次の
ごとくであつた。The properties of the purified terephthalic acid and the polyester obtained therefrom in a treated amount of 800 parts by weight of terephthalic acid were as follows.
４ＣＢＡ５ｐ，ｍｐ−イルイル酸 １８０ｐｐｍ０Ｄ
３４００．１６ポリエステルのｂ値 ２
゜５比較例３実施例３の反応塔を用い、入口部および仕
切部の水素供給管からそれぞれ、毎時１．０および１．
０容量部の割合で水素を供給した以外は、実施例３と全
く同様の精製処理を行ない、同じ粗テレフタル酸から処
理量８０００重量部の時点では、精製テレフタル酸の性
状は次のごとくであつた。4CBA5p,mp-yluyl acid 180ppm0D
3400.16 b value of polyester 2
゜5 Comparative Example 3 Using the reaction tower of Example 3, the hydrogen supply pipes at the inlet and the partition provided 1.0 and 1.0 ml per hour, respectively.
Except for supplying hydrogen at a rate of 0 parts by volume, the purification process was carried out in exactly the same manner as in Example 3, and when the amount of treated crude terephthalic acid was 8000 parts by weight, the properties of purified terephthalic acid were as follows. Ta.
４ＣＢＡ含量ｐ−トルイル酸含量０Ｄ３４０ポリエステルｂ値１５ｐｐｍ４５０ｐｐｍ０．１６３．４なお入口部での水素の対４ＣＢＡモル比は２．２３であ
つた。4CBA content p-toluic acid content 0D340 Polyester b value 15 ppm 45 0 ppm 0.16 3.4 The molar ratio of hydrogen to 4CBA at the inlet was 2.23.
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15664179AJPS5911573B2 (en) | 1979-12-03 | 1979-12-03 | Terephthalic acid purification method |
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15664179AJPS5911573B2 (en) | 1979-12-03 | 1979-12-03 | Terephthalic acid purification method |
| Publication Number | Publication Date |
|---|---|
| JPS5679635A JPS5679635A (en) | 1981-06-30 |
| JPS5911573B2true JPS5911573B2 (en) | 1984-03-16 |
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP15664179AExpiredJPS5911573B2 (en) | 1979-12-03 | 1979-12-03 | Terephthalic acid purification method |
| Country | Link |
|---|---|
| JP (1) | JPS5911573B2 (en) |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100398160B1 (en)* | 1999-09-07 | 2003-09-19 | 미쓰이 가가쿠 가부시키가이샤 | Process for producing aromatic carboxylic acid |
| Publication number | Publication date |
|---|---|
| JPS5679635A (en) | 1981-06-30 |
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