KR800001084B1 - Method for the preparation of terephthalic acid of high purity - Google Patents
Method for the preparation of terephthalic acid of high purity Download PDFInfo
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Abstract
Description
본 발명은 고순도 테레프탈산의 제조방법에 관한 것이다. 더 구체적으로는, 종래의 파라 디알킬벤젠의 액상 산화법을 개량하여 테레프탈산으로의 산화 반응이 실질적으로 종료된 후, 산화반응에 의해서 수득된 테레프탈산 슬러리에 다시 산소함유 가스를 주입해서 산화처리하여 고순도화시킴에 적합한 조건으로 액상 반응을 행함으로써, 직접 중합용 고순도 테레프탈산을 제조하는 방법에 관한 것이다.The present invention relates to a method for producing high purity terephthalic acid. More specifically, after the conventional liquid phase oxidation of paradialkylbenzene is substantially completed and the oxidation reaction to terephthalic acid is substantially terminated, oxygen-containing gas is injected into the terephthalic acid slurry obtained by the oxidation reaction and subjected to oxidation treatment for high purity. The present invention relates to a method for producing a high purity terephthalic acid for direct polymerization by performing a liquid phase reaction under conditions suitable for the application.
폴리에틸렌테레프탈레이트를 제조하는 방법으로서 테레프탈산 디알킬에스테르를 경유하는 방법에 대신해서 테레프탈산과 글리콜류를 직접 종합하는 방법이 주목되어 오고 있지만, 이것에 수반하여 테레프탈산이 고순도의 것 즉 예를들면 불순물인 4-카르복시벤즈알데히드(이하, 이것을 “4CBA”라고 약칭함)가 500ppm 이하인 것이 요구되고 있다.As a method for producing polyethylene terephthalate, a method of directly synthesizing terephthalic acid and glycols has been noted instead of a method of passing through terephthalic acid dialkyl esters, but with this, terephthalic acid has a high purity, that is, an impurity 4 -Carboxybenzaldehyde (hereinafter, abbreviated as "4CBA") is required to be 500 ppm or less.
그리하여, 공지의 파라디알킬벤젠의 액상 산화에 의해 수득되는 테레프탈산은 불순물로서 4CBA, 파라톨루일산 등의 반응 중간체, 혹은 구조 불명의 부반응 생성물을 다량으로 함유하고 있다. 파라디알킬벤젠의 테레프탈산으로의 액상 산화 반응이 실질적으로 종료된 후 수득되는 테레프탈산 현탁액을 그대로 또한 분자상 산소로 산화처리하는 방법이 알려져 있다(영국특허 제983,677호 참조).Thus, terephthalic acid obtained by liquid phase oxidation of known paradialkylbenzene contains a large amount of reaction intermediates such as 4CBA, paratoluic acid, or side reaction products of unknown structure as impurities. A method is known in which the terephthalic acid suspension obtained after the liquid phase oxidation of paradialkylbenzene to terephthalic acid is substantially terminated as it is and is also oxidized with molecular oxygen (see British Patent No. 983,677).
이 산화처리는 테레프탈산 슬러리의 모액중에 함유된 미량의 불순물, 특히 착색 원인 물질을 제거하는 것이며, 이 처리에 의해서 테레프탈산의 순도는 상당히 향상된다(이 산화처리를 이후 “후산화(after-oxidation)”라고 한다). 그러나, 이 방법만으로서는, 아직 충분히 만족할 만한 결과는 얻어지지 않는다.This oxidation treatment removes traces of impurities in the mother liquor of the terephthalic acid slurry, in particular the coloring agent, which greatly improves the purity of the terephthalic acid (this oxidation treatment is subsequently referred to as "after-oxidation". Is called). However, with this method alone, no satisfactory results are yet obtained.
본 발명자 등은 상기의 산화 및 후산화에 의해서 정제를 행하는 방법에 대해 여러가지로 검토한 결과, 후산화의 효과가 액상 산화시에 얻어지는 테레프탈산 현탁액의 모액중에 함유된 4CBA의 농도에 크게 좌우된다는 사실, 그리하여 이 모액중의 4CBA의 농도를 특정의 값 이하가 되도록 산화조건을 선택하여, 이 테레프탈산 현탁액에 대해서 후산화처리를 행하면 직접 중합용의 고순도, 즉 4 CBA 함량이 500ppm 이하인 테레프탈산이 용이하게 수득된다는 사실을 발견하고 본 발명에 도달하였다.As a result of various studies on the method of purifying by the above oxidation and post-oxidation, the present inventors and the like show that the effect of post-oxidation largely depends on the concentration of 4CBA contained in the mother liquor of the terephthalic acid suspension obtained at the time of liquid phase oxidation. When the oxidation conditions were selected so that the concentration of 4CBA in this mother liquor was lower than a specific value, and the post-oxidation treatment was performed on this terephthalic acid suspension, high purity for direct polymerization, that is, terephthalic acid having a content of 4 CBA of 500 ppm or less was easily obtained. And found the present invention.
즉, 본 발명은 저급 지방족 카르본산 용매 중에서 중금속을 함유하는 촉매의 존재하에, 산소 또는 산소함유 가스에 의해 파라디알킬벤젠 및 (또는) 그 산화 중간체를 액상산화하여 테레프탈산 현탁액을 얻는 제1공정 및 이 제1공정에서 얻어지는 테레프탈산 현탁액을 역시 산소 또는 산소 함유 가스에 의해 후산화 처리하는 제2공정을 포함하는 고순도 테레프탈산의 제조 방법에 있어서, 상기 제1공정의 액상산화를, 테레프탈산 현탁액의 모액중의 4CBA 농도를 약 800ppm 이하로 유지하면서 행하는 것을 특징으로 하는 고순도 테레프탈산의 제조방법에 관한 것이다.That is, the present invention provides a first step of obtaining a terephthalic acid suspension by liquid phase oxidation of paradialkylbenzene and / or its oxidizing intermediate with oxygen or an oxygen-containing gas in the presence of a catalyst containing a heavy metal in a lower aliphatic carboxylic acid solvent. In the method for producing high-purity terephthalic acid, which comprises a second step of post-oxidizing the terephthalic acid suspension obtained in the first step with oxygen or an oxygen-containing gas, the liquid oxidation of the first step is performed by 4CBA in the mother liquor of the terephthalic acid suspension. A method for producing high purity terephthalic acid, which is carried out while maintaining the concentration at about 800 ppm or less.
이하 본 발명에 대해서 더욱 상세히 설명한다. 본 발명 방법에 있어서는, 우선 제1공정에서 파라디알벤젠 및 (또는) 그 산화중간체는 저급 지방족 모노카르본산 용매중, 중금속을 함유하는 촉매의 존재하에 산소 또는 산소 함유 가스에 의해 액상화된다. 이 액상산화는 주지되어 있으며, 후술하는 요건을 만족하는 한 그 실시의 형태 및 조건의 여하는 문제가 되지 않는다.Hereinafter, the present invention will be described in more detail. In the method of the present invention, first, in the first step, the paradialbenzene and / or its intermediate oxide are liquefied with oxygen or an oxygen-containing gas in the presence of a catalyst containing heavy metal in a lower aliphatic monocarboxylic acid solvent. This liquid oxidation is well known, and as long as the requirements to be described later are satisfied, the embodiments and conditions thereof are not a problem.
원료로서 사용되는 파라디알킬벤젠에는, 가장 일반적으로 파라크실렌이 채용된다. 산화 중간체로서는, 예를들면 파라톨루일산 등을 들수 있다.As paradialkyl benzene used as a raw material, paraxylene is most commonly employed. As an oxidation intermediate, paratoluic acid etc. are mentioned, for example.
반응용매인 지방족 모노카르본산으로서는 공업적으로는 초산이 바람직하게 사용된다. 용매는 단독 또는 혼합물이어도 좋고, 소량의 물을 함유한 것이어도 좋다. 또, 이들의 용매에 대해서 알데히드류, 케톤류, 알코올류, 파라알데히드 중에시 선택된 유기 화합물의 1종 또는 2종 이상을 혼합하여 사용할 수도 있다. 용매는 통상 피산화물 1부에 대해 0.5∼20부, 바람직하기로는 1∼10부의 범위로 사용된다.As the aliphatic monocarboxylic acid as the reaction solvent, acetic acid is preferably used industrially. The solvent may be single or a mixture, or may contain a small amount of water. Moreover, 1 type (s) or 2 or more types of the organic compound selected from aldehydes, ketones, alcohols, and paraaldehyde can also be mixed with these solvents. The solvent is usually used in the range of 0.5 to 20 parts, preferably 1 to 10 parts with respect to 1 part of the blood oxide.
산화반응에 사용되는 중금속을 함유한 촉매로서는 주지의 촉매, 예를들면 코발트, 망간 등의 중금속 촉매를 들수가 있다. 이들의 중금속 촉매 이외에 취소화합물 혹은 알데히드류, 케톤류 등의 유기촉진제를 병용한 촉매를 사용할 수 있다. 이 중금속 화합물 촉매의 첨가량은 보통 용매에 대해서 0.001∼10중량%의 범위이다.As a catalyst containing a heavy metal used for an oxidation reaction, well-known catalysts, such as heavy metal catalysts, such as cobalt and manganese, are mentioned. In addition to these heavy metal catalysts, a catalyst using a combination of an organic accelerator such as a canceling compound or aldehydes or ketones can be used. The addition amount of this heavy metal compound catalyst is the range of 0.001 to 10 weight% normally with respect to a solvent.
산소 함유 가스로서는 산소 함유량 5∼100용량%의 것, 예를들면 공기를 사용할 수 있다. 반응계내에 공급되는 전산소량은 피산화물에 따라 달라지지만, 보통 피산화물1몰당 1∼100몰, 바람직하기로는 3∼100몰의 범위이다.As the oxygen-containing gas, an oxygen content of 5 to 100% by volume, for example, air can be used. The amount of total oxygen supplied into the reaction system varies depending on the pioxide, but is usually in the range of 1 to 100 mol, preferably 3 to 100 mol, per mol of the pioxide.
액상 산화 온도는 일반적으로 100∼250℃의 범위이고, 반응압력은 상압∼200기압, 특히 상압∼100 기압의 범위로부터 선택되지만, 어느 것이든지 반응계가 액상으로 유지되는 것이 필요하다.The liquid phase oxidation temperature is generally in the range of 100 to 250 ° C., and the reaction pressure is selected from the range of normal pressure to 200 atmospheres, in particular the normal pressure to 100 atmospheres, but in any case, the reaction system needs to be maintained in the liquid phase.
본 발명을 실시함에는 연속법 또는 반연속법이 적합하며, 생성되는 테레프탈산 현탁액의 모액의 4CBA 함량이 800ppm 이하인 것이 필요하다. 모액중의 4CBA 함량이 800ppm보다 많은 경우는 석출되는 테레프탈산 중에 혼입되는 불순물의 양이 많아지게 되고, 전술한 바와같이 후산화를 행하드라도 직접 중합용에 적합한 고순도 테레프탈산을 얻을 수 없다. 이 사실은 후술하는 실시예 1,2 및 비교예 1,2로 부터도 명백하다.In carrying out the present invention, a continuous method or a semi-continuous method is suitable, and it is necessary that the 4CBA content of the mother liquor of the resulting terephthalic acid suspension is 800 ppm or less. When the content of 4CBA in the mother liquor is more than 800 ppm, the amount of impurities mixed in the precipitated terephthalic acid increases, and as described above, even after post-oxidation, high purity terephthalic acid suitable for direct polymerization cannot be obtained. This fact is also apparent from Examples 1 and 2 and Comparative Examples 1 and 2 described later.
실시예 1,2는 액상 산화 현탁액 모액중의 4 CBA의 농도를 800ppm 이하로 억제하도록 산화반응을 행한 것이다. 그후, 후산화를 행하면 후산화 반응시간을 다소 단축해도(실시예 2)수득된 테레프탈산 중의 4CBA의 농도는 500ppm 이하로 억제할 수 있었다.Examples 1 and 2 were oxidized to suppress the concentration of 4 CBA in the liquid oxidizing suspension mother liquor to 800 ppm or less. Subsequently, if post-oxidation was performed, the concentration of 4CBA in the obtained terephthalic acid could be suppressed to 500 ppm or less even if the post-oxidation reaction time was shortened somewhat (Example 2).
또, 비교예 1에서는 액상 반응기에서의 체류 시간을 단축시킨 결과, 모액중의 4 CBA의 농도가 1,000ppm으로 높아지게 된다. 그리하여, 그후 후산화를 행해도 순도가 좋은 테레프탈산은 얻어지지 않는다.Moreover, in the comparative example 1, as a result of shortening the residence time in a liquid phase reactor, the density | concentration of 4 CBA in a mother liquid becomes high to 1,000 ppm. Thus, even after post-oxidation, terephthalic acid with high purity is not obtained.
비교예 2는 비교에 1과 동일한 반응조건으로, 후산화 시간만을 연장시킨 결과이다. 이것에 의하면, 냉각결정 석출후의 모액의 성상은 개선되었지만, 테레프탈산의 성상에는 전혀 변화가 보이지 않는다.Comparative Example 2 is the result of extending only the post-oxidation time under the same reaction conditions as those in the comparison. According to this, although the property of the mother liquid after cooling crystal precipitation improved, the property of terephthalic acid shows no change at all.
그 이유는 다음과 같이 설명할 수 있다. 즉, 후산화 반응의 온도는 전단계의 액상 산화 온도보다 낮게 설정되어 있기 때문에, 생성된 테레프탈산은 후산화 반응기 중에서 대부분이 석출된다. 그때 결정중에 함유된 4CBA는 후산화에 의해서도 산화되기 어렵고, 모액중에 남은 4CBA만이 산화되어 있기 때문이다.The reason can be explained as follows. That is, since the temperature of the post-oxidation reaction is set lower than the liquid phase oxidation temperature of the previous stage, most of the produced terephthalic acid precipitates in the post-oxidation reactor. This is because 4CBA contained in the crystal is hardly oxidized by post-oxidation, and only 4CBA remaining in the mother liquid is oxidized.
상기의 사실로부터, 고순도의 테레프탈산을 얻기 위하여는 액상산화에 의해 얻어지는 테레프탈산 현탁액의 모액중의 4 CBA의 농도는 800ppm을 넘지 않는 정도로 억제하지 않으면 안된다는 사실을 알 수있다.From the above facts, it can be seen that in order to obtain high purity terephthalic acid, the concentration of 4 CBA in the mother liquor of the terephthalic acid suspension obtained by liquid oxidation must be suppressed to a level not exceeding 800 ppm.
액상산화의 반응조건을 이와같이 설정하는 구체적인 방법으로서는 하기에 표시한 것을 들수가 있고, 이들을 또한 조합시킴으로써 공업적으로 유리한 조건을 설정할 수 있다.Specific methods for setting the reaction conditions for liquid phase oxidation in this manner include those shown below, and by combining them further, industrially advantageous conditions can be set.
(1) 연속방식의 경우에는, 그 체류시간을 길게한다. 이 경우, 체류시간은 극단으로 길게할 필요는 없고 예를들면 피산화물에 대한 용매량의 비가 3의 경우에는 체류시간은 2.5시간 정도로 충분하다.(1) In the case of continuous mode, the residence time is lengthened. In this case, the residence time does not have to be made extremely long. For example, when the ratio of the solvent amount to the oxide is 3, the residence time is sufficient as about 2.5 hours.
(2) 피산화물에 대한 용매량을 증가시킨다. 이것도 극단으로 많이 할 필요는 없고, 예를들면 연속방식의 경우는, 체류시간을 1시간으로 할때, 피산화물에 대한 용매량의 비는 6이면 충분하다.(2) Increase the amount of solvent for the pioxide. This does not have to be extremely extreme, for example, in the case of the continuous system, when the residence time is 1 hour, the ratio of the solvent amount to the oxidation target is 6 is sufficient.
물론, 상기의 (1),(2)에 기재한 수치는 기재한 것 이외의 조건에 의해서도 변화하는 것이다.Of course, the numerical value described in said (1), (2) changes also by conditions other than what was described.
(3) 산화반응액 중의 수분농도를 저지시킨다.(3) The concentration of water in the oxidation reaction solution is prevented.
(4) 반응기 중의 산소분압을 높인다.(4) Increase the oxygen partial pressure in the reactor.
(5) 반응액 중에서의 파라디알킬벤젠 및 산소 함유 가스의 분산을 향상시킨다.(5) Dispersion of paradialkylbenzene and oxygen-containing gas in the reaction solution is improved.
또, 본 발명에 있어서 테레프탈산 현탁액의 모액중의 4CBA의 농도는, 반응기로부터 테레프탈산 현탁액을 발출하여 고액(固液)을 분리한 후, 그 모액을 에스테르화하고, 이것을 가스크로마토그라피에 의해 측정한 것이다.In the present invention, the concentration of 4CBA in the mother liquor of the terephthalic acid suspension is obtained by extracting the terephthalic acid suspension from the reactor, separating the solid solution, and esterifying the mother liquor, which is measured by gas chromatography. .
이와 같이하여 얻어진 테레프탈산 현탁액은 계속하여 후산화 처리된다.The terephthalic acid suspension thus obtained is subsequently post-oxidized.
후산화의 방법은 연속방식의 경우와 반연속 방식과는 다르지만, 연속방식의 경우는 반응기로부터 취한 현탁액을 냉각결정 석출하기 전에, 또는 냉각결정 석출하는 단계에서 후산화조 혹은 결정 석출조중에서 반응이 행해진다. 반연속방의 경우에서는 반응종료 후 산화 반응기 중에서 그대를 실시할 수 있다.The post-oxidation method is different from the continuous method and the semi-continuous method, but in the continuous method, the reaction is carried out in the post-oxidation tank or the crystal precipitation tank before the cold crystal precipitation of the suspension taken from the reactor or during the cold crystal precipitation step. All. In the case of semi-continuous, it can be carried out in the oxidation reactor after the reaction is finished.
후산화에 사용하는 산소 함유 가스는 후산화를 충분히 행하기 위해 테레프탈산 현탁액 중의 반응 중간체를 더욱 산화시키는데 필요한 양보다 많이 하는 것이 바람직하다. 그러나, 너무 과잉으로 공급하면 용매 및 물이 증발하여, 후산화 온도가 저하되기 때문에 가열이 필요하게 되어 공업적으로 불리하다. 그리하여, 산소 가스의 유량을 적당히 선택하면 테레프탈산 현탁액을 다시 가열하지 않고 그대로 후산화시킬 수가 있다.The oxygen-containing gas used for the post-oxidation is preferably higher than the amount necessary to further oxidize the reaction intermediate in the terephthalic acid suspension in order to sufficiently perform the post-oxidation. However, when excessively supplied, solvent and water will evaporate and post-oxidation temperature will fall, and heating is required and it is industrially disadvantageous. Thus, if the flow rate of the oxygen gas is appropriately selected, the terephthalic acid suspension can be post-oxidized as it is without being heated again.
후산화에 공급되는 산소 함유 가스는 전단계의 산화반응에서 사용되는 산소에 대해, 피산화물의 양이 적으므로 1/1,000∼1/10로 적게한다. 전단계의 산화반응의 폐가스 중의 산소농도가 높은 경우에는, 그 폐가스의 일부를 후산화용의 가스로서 이용할 수도 있으며, 또, 그 폐가스를 새로이 산소 함유 가스와 혼합하여 이용할 수도 있다.The oxygen-containing gas supplied to the post-oxidation is reduced to 1 / 1,000 to 1/10 because of the small amount of the oxide to be used for the oxygen used in the previous stage of the oxidation reaction. When the oxygen concentration in the waste gas of the previous stage of oxidation reaction is high, a part of the waste gas may be used as the gas for post-oxidation, and the waste gas may be newly mixed with the oxygen-containing gas.
후산화 반응의 온도는 전단계의 애상 산화 온도보다 낮은 온도가 바람직하며, 실제로는 반응온도로 부터 30℃까지의 범위가 바람직하다. 물론, 반응온도 이상에서도 좋지만 다시 가열을 필요로 하므로 공업적으로 불리하다.The temperature of the post-oxidation reaction is preferably lower than the frost-oxidation temperature of the previous stage, and in practice, the range of the reaction temperature from 30 ° C is preferred. Of course, the reaction temperature is good, but it is industrially disadvantageous because it requires heating again.
또, 촉매는 후산화의 단계에서 새로이 첨가할 수도 있으며, 추가하지 않아도 좋다.In addition, the catalyst may be newly added in the post-oxidation step, and may not be added.
다음에 본 발명의 실시예를 나타낸다.Next, the Example of this invention is shown.
[실시예 1]Example 1
환류 냉각장치, 교반장치, 가열장치, 원료 및 촉매를 함유하는 용매의 송입구, 가스 도입구 및 반응 현탁액 발출구를 갖춘 티탄합금제의 내압 애상 산화 반응기, 환류 냉각 장치, 교반장치, 가스 도입구 및 테레프탈산 현탁액의 송입구와 발출구를 갖춘 티탄합금제 내압후산화 반응장치 및 냉각결정 석출기를 사용해서 연속 애상 산화를 실시했다.Pressure-resistant frost oxidation reactor of titanium alloy, reflux cooling device, stirring device, gas inlet with reflux condenser, stirring device, heating device, feed inlet of raw material and catalyst, gas inlet and reaction suspension outlet And continuous phase defrost oxidation using a titanium alloy internal pressure after-oxidation reactor equipped with an inlet and an outlet of the terephthalic acid suspension and a cooling crystal precipitater.
애상 산화 반응기에, 판라크실렌 1중량부, 초산 2.85부, 초산 코발트(4 수화물) 0.004부, 초산망간(4수화물) 0.0008부, 취화나트륨 0.0036부 및 물 0.15부의 비율로 각 원료를 연속적으로 공급하고, 애상 산화 반응기에서의 체류시간이 175분이 되도록 산화반응을 행했다. 산화 가스로서는 공기를 사용하고, 반응기 폐가스 중의 산소 농도가 4용량%가 되도록 반응기 중에 공급했다. 산화 반응온도는 210℃, 압력은 25kg/㎤, 로 유지했다.Each raw material was continuously supplied to the oxidized oxidation reactor at a ratio of 1 part by weight of panlaxylene, 2.85 parts of acetic acid, 0.004 parts of cobalt acetate (tetrahydrate), 0.0008 parts of manganese acetate (tetrahydrate), 0.0036 parts of sodium embrittlement, and 0.15 parts of water. The oxidation reaction was carried out such that the residence time in the oxidized oxidation reactor was 175 minutes. Air was used as the oxidizing gas, and the gas was fed into the reactor so that the oxygen concentration in the reactor waste gas was 4% by volume. The oxidation reaction temperature was maintained at 210 ° C. and the pressure at 25 kg / cm 3.
수득된 테레프탈산 현탁액은 후산화 반응기에 공급하여, 온도 190℃, 압력 17.5kg/㎤, 체류시간 85분의 조건으로 후산화를 행했다. 그때의 산화용 가스는 전단계의 산화 반응 폐가스와 공기와를 혼합하여 산소 농도 10용량%로 한 것을 사용하고, 후산화 폐가스중의 산소농도가 4용량%가 되도록 공급했다.The obtained terephthalic acid suspension was fed to a post-oxidation reactor, and post-oxidation was performed on conditions of the temperature of 190 degreeC, the pressure of 17.5 kg / cm <3>, and a residence time of 85 minutes. The oxidizing gas at that time was made to mix the oxidation reaction waste gas of the previous stage with air, and to make the oxygen concentration 10 volume%, and it supplied so that the oxygen concentration in the post-oxidation waste gas might be 4 volume%.
후산화 처리시킨 테레프탈산 현탁액은 다음에 100℃의 결정 석출기에 이송하고, 결정석출 후 고액 분리했다.The post-oxidation terephthalic acid suspension was then transferred to a crystallizer at 100 ° C., and solid-liquid separation was carried out after crystallization.
수득된 테레프탈산은 4중량배의 초산중에서 교반하에 80℃에서 20분간 현탁세척시키고, 다시 고액분리한후 건조했다.The obtained terephthalic acid was suspended and washed for 20 minutes at 80 ° C. under stirring in 4 wt. Times of acetic acid, and then solid-liquid separated and dried.
얻어진 테레프탈산의 성상은 제1표와 같았다.The properties of the obtained terephthalic acid were the same as in the first table.
또, 산화반응 기중의 현탁액의 모액의 성상 및 냉각결정 석출후의 모액의 성상은 각각 제2표 및 제3표와 같았다.In addition, the properties of the mother liquid of the suspension in the oxidation reaction group and the properties of the mother liquid after cooling crystal precipitation were the same as those in Tables 2 and 3, respectively.
[실시예 2]Example 2
산화 반응기에서의 체류시간을 80분, 후산화 반응기에서의 체류시간을 45분, 온도를 190℃, 압력을 16kg/㎤로 한 것 이외에는, 실시예 1과 동일한 조건으로 테레프탈산의 제조를 행했다.Terephthalic acid was produced on the same conditions as in Example 1 except that the residence time in the oxidation reactor was 80 minutes, the residence time in the post oxidation reactor was 45 minutes, the temperature was 190 ° C, and the pressure was 16 kg / cm 3.
수득된 테레프탈산의 성상, 산화반응기 중의 현탁액의 모액의 성상 및 냉각 결정석출 후의 모액의 성상은 각각 제1표, 제2표 및 제3표와 같았다.The properties of the obtained terephthalic acid, the properties of the mother liquor of the suspension in the oxidation reactor, and the properties of the mother liquor after cooling crystallization were as in Tables 1, 2, and 3, respectively.
[실시예 3]Example 3
파라크실렌 1부에 대해서 촉매를 함유하는 초산 수용액의 사용량을 6부로 하고, 산화 반응기에서의 체류시간을 109분, 후산화 반응기에서의 체류시간 53분, 온도 195℃, 압력 17.5kg/㎤로 한 것 이외에는 실시예 1과 동일한 조건으로 테레프탈산의 제조를 행했다.For 1 part of paraxylene, the amount of acetic acid solution containing catalyst was 6 parts, and the residence time in the oxidation reactor was 109 minutes, the residence time 53 minutes in the post oxidation reactor, the temperature was 195 ° C, and the pressure was 17.5 kg / cm 3. Except for the above, terephthalic acid was produced under the same conditions as in Example 1.
수득된 테레프탈산의 성상, 산화 반응기 중의 현탁액의 모액의 성상 및 냉각 결정석출 후의 모액의 성상은 각각 제1표, 제2표 및 제3표와 같았다.The properties of the obtained terephthalic acid, the properties of the mother liquor of the suspension in the oxidation reactor, and the properties of the mother liquor after cooling crystallization were the same as those in Tables 1, 2, and 3, respectively.
[비교예 1]Comparative Example 1
산화 반응기에서의 체류시간을 57분으로 한 것 이외는 실시예 1과 동일한 조건으로 테레프탈산의 제조를 행했다.Terephthalic acid was manufactured on the conditions similar to Example 1 except having set the residence time in the oxidation reactor to 57 minutes.
[비교예 2]Comparative Example 2
비교예 1의 테레프탈산 제조시에 후산화 반응기에서의 체류시간을 85분으로부터 180분으로 변경했다.In the preparation of terephthalic acid of Comparative Example 1, the residence time in the post-oxidation reactor was changed from 85 minutes to 180 minutes.
비교예 1,2에서 수득된 테레프탈산의 성상, 산화 반응기중의 현탁액의 모액의 성상, 냉각결정 석출후의 모액의 성상은 각각 제1표, 제2표 및 제3표와 같았다.The properties of the terephthalic acid obtained in Comparative Examples 1 and 2, the properties of the mother liquid of the suspension in the oxidation reactor, and the properties of the mother liquid after cooling crystal precipitation were the same as in the first, second and third tables, respectively.
[비교예 3]Comparative Example 3
후산화를 생략한 것 이외에는 실시예 1과 동일한 조건으로 테레프탈산의 제조를 행했다.Terephthalic acid was produced on the same conditions as in Example 1 except that post-oxidation was omitted.
수득된 테레프탈산의 성상은 제1표와 같았다.The properties of the obtained terephthalic acid were the same as in the first table.
[제1표][Table 1]
주) 1) 및 2)의 투과율은 테레프탈산 15부를 100부의 2 수산화칼륨에 융해하여 광로장(光路長) 1cm의 석영 셀로 측정한 것이다.Note) The transmittances of 1) and 2) were measured by quartz cell having a light path length of 1 cm by melting 15 parts of terephthalic acid into 100 parts of potassium hydroxide.
[제2표][Table 2]
[제3표][Table 3]
[참고예][Reference Example]
실시예 및 비교예에서 수득된 테레프탈산을 주지의 방법에 따라서 에틸렌글리콜과 직접 중합하여 폴리머를 제조했다. 수득된 폴리머의 색상을 아래표에 나타냈다.The terephthalic acid obtained in Examples and Comparative Examples was directly polymerized with ethylene glycol according to a known method to prepare a polymer. The color of the obtained polymer is shown in the table below.
* 조제(粗製) 테레프탈산을 고온, 고압하에서 물에 용해하고, 팔라듐 촉매로 처리하여 정제한 고순도 테레프탈산.* High purity terephthalic acid which was prepared by dissolving the prepared terephthalic acid in water under high temperature and high pressure and treating it with a palladium catalyst.
Claims (1)
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8783574A JPS5614101B2 (en) | 1974-07-31 | 1974-07-31 |
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| KR800001084B1 true KR800001084B1 (en) | 1980-10-06 |
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| KR7501539A KR800001084B1 (en) | 1974-07-31 | 1975-07-15 | Method for the preparation of terephthalic acid of high purity |
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| Country | Link |
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| JP (1) | JPS5614101B2 (en) |
| KR (1) | KR800001084B1 (en) |
| BR (1) | BR7504901A (en) |
| DE (1) | DE2534161C2 (en) |
| FR (1) | FR2280626A1 (en) |
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| IT (1) | IT1041434B (en) |
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| DE3063298D1 (en) | 1979-07-02 | 1983-07-07 | Ici Plc | Process for the preparation of terephthalic acid |
| JPH0213652U (en) * | 1988-07-11 | 1990-01-29 | ||
| US7485747B2 (en) | 2001-06-04 | 2009-02-03 | Eastman Chemical Company | Two stage oxidation process for the production of aromatic dicarboxylic acids |
| US7196215B2 (en) | 2001-06-04 | 2007-03-27 | Eastman Chemical Company | Process for the production of purified terephthalic acid |
| US20040215036A1 (en) | 2003-04-25 | 2004-10-28 | Robert Lin | Method for heating a crude carboxylic acid slurry in a post oxidation zone by the addition of steam |
| US7326808B2 (en) | 2006-03-01 | 2008-02-05 | Eastman Chemical Company | Polycarboxylic acid production system employing cooled mother liquor from oxidative digestion as feed to impurity purge system |
| US7420082B2 (en) | 2006-03-01 | 2008-09-02 | Eastman Chemical Company | Polycarboxylic acid production system employing hot liquor removal downstream of oxidative digestion |
| US7326807B2 (en) | 2006-03-01 | 2008-02-05 | Eastman Chemical Company | Polycarboxylic acid production system with enhanced heating for oxidative digestion |
| US20070208194A1 (en) | 2006-03-01 | 2007-09-06 | Woodruff Thomas E | Oxidation system with sidedraw secondary reactor |
| US7393973B2 (en) * | 2006-03-01 | 2008-07-01 | Eastman Chemical Company | Polycarboxylic acid production system with enhanced residence time distribution for oxidative digestion |
| US7501537B2 (en) | 2006-03-01 | 2009-03-10 | Eastman Chemical Company | Polycarboxylic acid production system employing oxidative digestion with reduced or eliminated upstream liquor exchange |
| US7816556B2 (en) | 2006-03-01 | 2010-10-19 | Eastman Chemical Company | Polycarboxylic acid production system employing enhanced multistage oxidative digestion |
| US7772424B2 (en) | 2006-03-01 | 2010-08-10 | Eastman Chemical Company | Polycarboxylic acid production system employing enhanced evaporative concentration downstream of oxidative digestion |
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| GB983677A (en) * | 1962-04-27 | 1965-02-17 | Mitsui Petrochemical Ind | A process for the preparation of terephthalic acid having extremely high purity |
| CA793870A (en) * | 1964-12-14 | 1968-09-03 | Berthoux Jean | Procede d'oxydation d'hydrocarbures aromatiques |
| FR2113424A5 (en) * | 1970-11-01 | 1972-06-23 | Maruzen Oil Co Ltd |
-
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- 1974-07-31 JP JP8783574A patent/JPS5614101B2/ja not_active Expired
-
1975
- 1975-07-15 KR KR7501539A patent/KR800001084B1/en active
- 1975-07-30 IT IT68980/75A patent/IT1041434B/en active
- 1975-07-30 FR FR7523829A patent/FR2280626A1/en active Granted
- 1975-07-31 BR BR7504901A patent/BR7504901A/en unknown
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| Publication number | Publication date |
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| JPS5614101B2 (en) | 1981-04-02 |
| JPS5116630A (en) | 1976-02-10 |
| DE2534161A1 (en) | 1976-02-12 |
| GB1454478A (en) | 1976-11-03 |
| DE2534161C2 (en) | 1983-08-18 |
| IT1041434B (en) | 1980-01-10 |
| FR2280626A1 (en) | 1976-02-27 |
| FR2280626B1 (en) | 1980-04-18 |
| BR7504901A (en) | 1977-03-01 |
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