1359133 九、發明說明： 【發明所屬之技術領域】 本發明係關於一種用以製備純化對苯二甲酸的方法。 【先前技術】 純化對苯二曱酸（PTA)係一種具相當商業重要性的商 品化石油化學物。其作為用以製造不同種類聚合物的關鍵 原料物質。世界生產PTA的產能每年超過25百萬噸。聚合 ® 物或是純化對苯二甲酸係作為聚乙烯對苯二甲酸酯的起始 物質，聚乙烯對苯二曱酸酯則係主要用以製造聚酯纖維、 聚酯薄膜以及用以製造瓶罐與相似容器的樹脂。純化對苯 二甲酸係從相對純度較低、技術級或是粗製對苯二曱酸 (CTA)而製造販售。粗製對苯二曱酸可從通常含有相對大量 不同種類雜質的對二甲苯經氧化而獲得。此等雜質可包含 下列物種。出現CTA中的有機雜質包含部分氧化產物，像 φ 是對羥基苯曱醛（4-CBA)(〜3000 ppm)以及對羥基苯曱 醒1的氫化產物-對甲苯曱酸（〜500 ppm)。具顏色雜質可包 含乙醇酸、芴酮（f luorenone)或是蔥（Anthraquinone ) (〜30 ppm)。金屬雜質包含鐵以及其他金屬（〜85 ppm)。除 此之外，溼度（〜0.2%)以及灰份（〜100 ppm)可以雜質出 現。下列表一顯示粗製對苯二曱酸以及純化對苯二曱酸的 參數值。PTA的參數對於做為進行聚合反應的起始物質係 必須的。 6 1359133 表1 CTA以及PTA參數 特性 χ)Ό — 早兀 CTA PTA 純度 % 99.7 99.95 4-CBA ppm 2500 <25 對曱苯 曱酸 ppm 500 < 150 APHA Color HU 50 <10 DELTA-Y 30 <10 b-Value 9 〈2.5 灰份 ppm 100 <10 溼度 % 0.2 < 0.1 全體金屬 ppm 85 <10 可藉由在碳上所具鈀催化劑將中間粗製對苯二曱酸進 行催化性加氫反應，而製備出PTA。加氫反應係在280°C 的高溫以及80 bar的高壓下，於一水性溶液中進行。接著 進行結晶反應、熱過濾以及熱洗滌並且乾燥以獲得純度超 過 99, 95%的 PTA。 US 5,567,842揭露一種用以製備純化對苯二曱酸的 方法，其中加氫步驟係在連續固定床式反應器中實施，據 此始漿液轉送至複數個結晶器，其中該溫度係藉由壓力釋 1359133 ► 放冷卻而下降。 US 3,584,039揭露一種於一批次反應器中製備純化 對苯二曱酸的方法。再者，加氫反應器係藉由釋放壓力將 水自溶液中蒸發出並且冷卻該溶液，從而沉澱出對苯二曱 酸結晶物。所獲得對苯二曱酸結晶物於室溫過濾。 甚者，US 5, 767, 311揭露一種自一液態分散劑純化粗 製對苯二曱酸，其中此方法不包含一氫化步驟，但粗製對 苯二甲酸僅藉由結晶反應以及過濾步驟而純化。 已知用以製備純化對苯二甲酸的方法具有一些缺失， 大部分，CTA的催化性加氫反應係在一固定床内實施並且 需要低濃度的饋料。進一步，氫化反應以及結晶反應係經 常於不同反應器中分別進行者，並且數個階段結晶反應係 共同的。額外地，結晶反應係藉由水溶劑蒸發冷卻（減壓） 而進行，其建構在結晶反應反應器的器壁上。最後，同樣 亦個別經過熱過;慮以及熱洗蘇’並且在熱過滤·後措由再聚 化而獲得固態產物。因此，發生材料的損失並且徒增廢水 以及耗能。 【發明内容】 本發明的目的係提供一種用以製備純化對苯二曱酸的 方法，其用以克服習知技術的缺失。 本目的係藉由一種用以製備純化對苯二曱酸的方法 (PTA)而達成，包括下列步驟： i)在一反應器中將粗製對苯二曱酸（CTA)溶解一水溶性 1359133 介質中； ii) 在一溫度約260-320°C並且在一壓力約1100-1300 psig 下使用一加氫催化劑氫化對苯二曱酸； iii) 藉由降低該溶液的溫度至約160°C而無需進行蒸發冷 卻，於該反應器内進行對苯二甲酸結晶； iv) 將該反應器内容物轉移至一過濾單元； v) 在一溫度約140-160°C並且在一壓力約40-100psig下 過濾該内容物，較佳者係在壓力80-100psig下以獲得一過 滤·糕狀物， vi) 以溫度約140-160°C的水，在該過濾單元内洗滌所得之 該過溏糕狀物；以及 vii) 乾燥該過濾糕狀物。 較佳者，本方法係在一批次反應器中實施。 尤有較佳者，於步驟i)至步驟iii)中該反應器内容物 係利用轉速約250 - 400 rpm的一攪拌器進行混合。 在一實施例中，於該反應器内設置一含有該加氫催化 劑之催化劑筐。 較佳者催化劑筐係由鈦以及雙相不銹鋼兩者之一所製 成者。 更佳者係該加氫催化劑含有鉑族金屬，其係選自由 在巴、釕、鍵、锇、鈒以及鈾所組成的族群或是其氧化物。 較佳者係該加氫催化劑為一載體所支撐。 最佳者係該加氫催化劑係活性碳為載體上的鈀。 在一實施例中，該水溶性介質係水，較佳者係去礦物 91359133 IX. Description of the Invention: TECHNICAL FIELD OF THE INVENTION The present invention relates to a process for preparing purified terephthalic acid. [Prior Art] Purification of terephthalic acid (PTA) is a commercially valuable petrochemical of considerable commercial importance. It serves as a key raw material for the manufacture of different types of polymers. The world's production capacity of PTA exceeds 25 million tons per year. Polymerization® or purified terephthalic acid as the starting material for polyethylene terephthalate, polyethylene terephthalate is mainly used to make polyester fiber, polyester film and used in manufacturing Bottles and resins in similar containers. Purified terephthalic acid is sold from relatively low purity, technical grade or crude terephthalic acid (CTA). The crude terephthalic acid can be obtained by oxidation of p-xylene which usually contains a relatively large amount of different kinds of impurities. These impurities may include the following species. The organic impurities in the CTA appear to contain partial oxidation products, such as φ being p-hydroxybenzaldehyde (4-CBA) (~3000 ppm) and p-hydroxyphenyl hydrazine 1 hydrogenated product - p-toluic acid (~500 ppm). Color impurities can include glycolic acid, fluorenone (f luorenone) or onion (Anthraquinone) (~30 ppm). Metal impurities include iron as well as other metals (~85 ppm). In addition, humidity (~0.2%) and ash (~100 ppm) can be present as impurities. Table 1 below shows the values of crude terephthalic acid and purified terephthalic acid. The parameters of the PTA are necessary for the starting material for the polymerization. 6 1359133 Table 1 CTA and PTA parameters characteristics Ό) Ό — early CTA PTA purity% 99.7 99.95 4-CBA ppm 2500 <25 p-benzoquinone ppm 500 < 150 APHA Color HU 50 <10 DELTA-Y 30 <10 b-Value 9 <2.5 ash ppm 100 < 10 humidity % 0.2 < 0.1 total metal ppm 85 < 10 The intermediate crude terephthalic acid can be catalytically supported by a palladium catalyst on carbon The hydrogenation reaction is carried out to prepare PTA. The hydrogenation reaction was carried out in an aqueous solution at a high temperature of 280 ° C and a high pressure of 80 bar. Next, a crystallization reaction, hot filtration, and hot washing were carried out and dried to obtain PTA having a purity exceeding 99, 95%. No. 5,567,842 discloses a process for the preparation of purified terephthalic acid wherein the hydrogenation step is carried out in a continuous fixed bed reactor whereby the slurry is transferred to a plurality of crystallizers, wherein the temperature is released by pressure 1359133 ► Drop by cooling. No. 3,584,039 discloses a process for the preparation of purified terephthalic acid in a batch reactor. Further, the hydrogenation reactor evaporates water from the solution by releasing pressure and cools the solution, thereby precipitating the crystal of terephthalic acid. The obtained terephthalic acid crystals were filtered at room temperature. No. 5,767,311 discloses the purification of crude terephthalic acid from a liquid dispersant wherein the process does not comprise a hydrogenation step, but the crude terephthalic acid is purified only by the crystallization reaction and the filtration step. It is known that the process for preparing purified terephthalic acid has some drawbacks. Most of the catalytic hydrogenation of CTA is carried out in a fixed bed and requires a low concentration of feed. Further, the hydrogenation reaction and the crystallization reaction are carried out separately in different reactors, and the crystallization reaction is common to several stages. Additionally, the crystallization reaction is carried out by evaporation (depressurization) by evaporation of a water solvent, which is constructed on the wall of the crystallization reactor. Finally, the same is also done separately by heat; considering and hot washing, and re-polymerization after hot filtration to obtain a solid product. As a result, material losses occur and wastewater and energy consumption are increased. SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for preparing purified terephthalic acid which overcomes the deficiencies of the prior art. The object is achieved by a method for preparing purified terephthalic acid (PTA) comprising the following steps: i) dissolving crude terephthalic acid (CTA) in a reactor to dissolve a water-soluble 1359133 medium Ii) hydrogenating terephthalic acid at a temperature of about 260-320 ° C and at a pressure of about 1100-1300 psig using a hydrogenation catalyst; iii) by lowering the temperature of the solution to about 160 ° C Crystallization of terephthalic acid is carried out in the reactor without evaporative cooling; iv) transferring the contents of the reactor to a filtration unit; v) at a temperature of about 140-160 ° C and at a pressure of about 40-100 psig The contents are filtered down, preferably at a pressure of 80-100 psig to obtain a filter cake, vi) washed at a temperature of about 140-160 ° C in the filter unit. And vii) drying the filtered cake. Preferably, the process is carried out in a batch reactor. More preferably, the contents of the reactor in steps i) through iii) are mixed using a stirrer having a rotational speed of about 250 - 400 rpm. In one embodiment, a catalyst basket containing the hydrogenation catalyst is disposed in the reactor. Preferably, the catalyst basket is made of one of titanium and duplex stainless steel. More preferably, the hydrogenation catalyst contains a platinum group metal selected from the group consisting of Ba, bismuth, bond, ruthenium, osmium and uranium or an oxide thereof. Preferably, the hydrogenation catalyst is supported by a carrier. Most preferably, the hydrogenation catalyst-based activated carbon is palladium on a support. In one embodiment, the water soluble medium is water, preferably demineralized 9
⑧I 1359133 質水（demineralized water) ° 進一步言之，本方法的優點在於步驟ii)中進行氫化所 需時間係至少6小時，較佳者係至少7小時，最佳者係至 少8小時。 較佳者係於步驟ii)中係以約l°C/min速率降溫至溫 度約160°C。 最佳者，於步驟iii)中溫度達到約160〇C後’藉由蒸 發使該反應器減壓至壓力約100 psig。 尤有較佳者係該溫度在溫度到達約16 〇。C後即維持在 此溫度。 在一實施例中，於步驟iv)中的轉移係透過在溫度維 持在約180 -250°C的一轉移線而實施者。 其中於步驟vi)所使用的水係在該反應器中並在壓力 約100 psig下被加熱係有利的。 尤有較佳者，係於步驟Π)中所進行之降低溫度，係藉 •由將冷卻劑流通至設置於該反應器或設置於其中的冷卻^ 環迴圈而達成者。 較佳者，該冷卻劑係水，較佳者係溫度約1〇 — 的涼水。 最後，較佳者係於步驟〇中所含PTA係藉於約5 —的 重量百分，其係相對於PTA以及水溶性介質的總重。 則本發明 ’使對笨 出人意料，發現如果本方法利用下列步驟， 的方法之數個優點可被達成： ""、 、、勺 16 0 需蒸發冷卻 二甲酸於加氫反應器内結晶，以及 ' 轉移加氫反應器的内容物至能實施過濾以及洗、欠 .兀。進-步言之，相較於習知技術所使用的固定床私單 明有利於使用—連續攪拌加氫反應ϋ。 ’本發 透過反應溫度的降低並且非藉由減壓而使氯 4 _酸溶液冷卻’並非建構在加氫反應器的器壁上。進:二 5之’熱過濾以及熱洗務可於一過渡單元内進行而益步 #所獲得固態產物再襞化，因此可控制材料的損失。‘、、、需將 如以上所略述者，為進行結晶反應的冷卻僅藉由 該溫度而非因減壓被影響。然而在冷卻期間壓力自動低 至約250 - 300 psig。在冷卻溫度至約16〇〇c後，壓力可1 後藉由去壓至100psi而進一步較佳地降低。此可避免二= 的冷卻並且製備出的產物具有良好品質，顆粒具有良二， 型以及高純度的產物。此ΡΤΑ顆粒的分布集中並帶有^外 細微顆粒。此顆粒亦具有良好強度。進一步言之，〜數 #低溫度下的去壓過程具有其他優點，像是將結晶物攜^ 通風線（vent line)的情況可被避免，因此避免了 生= 工廠發生阻塞的共同問題。 —產 其=較佳地轉移線的溫度維持在高於結晶反應器以及 熱過遽單元的溫度。此可避免在轉移線内因為突然冷邱所 致的阻塞。 【實施方式】 其他優點以及特徵將針對一種用以製備純化對笨二甲8I 1359133 demineralized water ° Further, the method has the advantage that the time required for hydrogenation in step ii) is at least 6 hours, preferably at least 7 hours, and most preferably at least 8 hours. Preferably, in step ii), the temperature is lowered to a temperature of about 160 ° C at a rate of about 1 ° C/min. Most preferably, after the temperature in step iii) reaches about 160 ° C, the reactor is depressurized by evaporation to a pressure of about 100 psig. Particularly preferred is that the temperature reaches about 16 Torr at temperature. It is maintained at this temperature after C. In one embodiment, the transfer in step iv) is carried out by a transfer line maintained at a temperature of between about 180 and 250 °C. The water used in step vi) is advantageously heated in the reactor at a pressure of about 100 psig. More preferably, the temperature reduction performed in step Π) is achieved by circulating a coolant to a cooling loop provided in the reactor or disposed therein. Preferably, the coolant is water, preferably cold water having a temperature of about 1 Torr. Finally, it is preferred that the PTA contained in the step is based on a weight percentage of about 5 Å, which is relative to the total weight of the PTA and the water-soluble medium. The present invention is surprisingly surprising, and it has been found that several advantages of the method can be achieved if the method utilizes the following steps: "", ,, spoon 16 0 requires evaporation of the dicarboxylic acid to crystallize in the hydrogenation reactor, And 'transfer the contents of the hydrogenation reactor until it can be filtered and washed, owed. Further, it is advantageous to use the fixed bed private unit used in the prior art - continuous stirring of the hydrogenation reaction. The present invention is not constructed on the wall of the hydrogenation reactor by the reduction of the reaction temperature and the cooling of the chlorine-acid solution without decompression. In addition: the thermal filtration and hot washing can be carried out in a transition unit and the solid product obtained is re-deuterated, thus controlling the loss of material. ‘,,,, as will be described above, the cooling for the crystallization reaction is only affected by the temperature rather than by the reduced pressure. However, the pressure is automatically reduced to approximately 250 - 300 psig during cooling. After cooling to about 16 〇〇c, the pressure can be further preferably further reduced by depressurization to 100 psi. This avoids the cooling of two = and the prepared product has good quality, and the particles have a good quality, a high purity product. The distribution of the ruthenium particles is concentrated with fine particles. This granule also has good strength. Further, the decompression process at ~ low temperature has other advantages, such as the case where the crystallizer is carried over the vent line, thus avoiding the common problem of the occurrence of blockage in the factory. - Produce it = preferably the temperature of the transfer line is maintained above the temperature of the crystallization reactor and the thermal enthalpy unit. This avoids blockages in the transfer line due to sudden cold. [Embodiment] Other advantages and features will be directed to a method for preparing purified
11 1359133 酸的方法藉由下列例子詳細的描述以及圖式而被了解，其 中： 第一圖表不利用本發明的方法於不同氫化時間所得對 羥基苯曱醛内容物的比較； 第二圖係表示於本發明方法中之熱過濾後對曱苯曱酸 内容物的比較； 第三圖係表示於本發明方法中之熱洗滌後對曱苯曱酸 内容物的比較； 第四圖係表示於本發明方法中使用不同金屬内容物作 為催化劑催化劑筐的材料之比較；以及 第五圖藉由本發明方法所獲得純化對苯二甲酸所具有 的顏色特性之比較。 化學物質.使用於每一批用以將c TA轉換至p τA所使用 的化學物質之品質與來源如下述：使用！ 25 kg商品化㈣ 於一加虱反應器内進行一加氫反應並且將32公克鈀催化劑 於-碳支撐物（可購得自Sud_Chemie或是㈣他㈣。所使 用的氫氣純度達99%並且所使㈣去離子水之料度小於 準備饋料：用於加氫反應的饋料混合物係藉由首先〇 供給真空將水饋送進人該反應^製備者。接著使用則 手動添加I.25 kgCT场末至該反應^此混合物隨後在賴 ^2〇rpmT_以得到含有約135重量百分的對苯二甲越 ‘二反應器而使壓力達到5~哗並且及 匆胁54，以及隨後藉由打開〜氣閥釋放氣體 135913311 1359133 The method of acid is understood by the following detailed description of the examples and the drawings, wherein: the first chart does not utilize the method of the invention to compare the contents of p-hydroxybenzaldehyde obtained at different hydrogenation times; Comparison of the contents of indomethacin after hot filtration in the method of the present invention; the third figure shows the comparison of the content of indomethacin after hot washing in the method of the present invention; the fourth figure is shown in A comparison of materials using different metal contents as catalyst catalyst baskets in the inventive method; and a comparison of the color characteristics of purified terephthalic acid obtained by the method of the present invention. Chemicals. The quality and source of the chemicals used in each batch to convert c TA to p τA are as follows: Use! 25 kg commercialization (iv) A hydrogenation reaction is carried out in a one-twist reactor and 32 g of palladium catalyst is supported on a carbon support (commercially available from Sud_Chemie or (iv) he (four). The purity of the hydrogen used is 99% and The feedstock of (iv) deionized water is less than the feedstock to be fed: the feed mixture for the hydrogenation reaction is fed to the reactor by first supplying a vacuum to the reactor, and then manually adding an I.25 kg CT field. The reaction was then carried out at 〇 〇 T _ _ _ 以 以 以 以 含有 含有 含有 含有 含有 含有 含有 含有 含有 含有 含有 含有 含有 含有 含有 含有 含有 含有 含有 哗 哗 哗 哗 哗 哗 哗 哗 哗 哗 哗 哗 哗 哗 哗 哗 哗Open ~ air valve to release gas 1359133
Psig。於力π氫反應器 ，例如在該反應器内 將該反應器内的氮氣壓力維持在1〇 中，固定一含有加氫催化劑之催化劑 的一冷卻迴圈。 加氫反應：CTA的加氫反應以轉換主要雜質對羥基苯 曱醛（4-CBA)成為P-t〇luic aicd係在溫度285〇C下進行，並 且該反應器的壓力維持在12〇〇 psig，即超過水分壓以維持 在液相並且確保合適的氫氣供應。加氫反應係以不同時間 φ間隔進行者，在供應氫氣供應，當壓力降低並且達到水分 壓時用以維持在定壓。 結晶化：加氫反應結束後，將加氫反應器關掉並且將 該反應器的溫度藉由將溫度約10 - 15°C的涼水流通至設置 於該加氫反應器或設置於其中的冷卻循環迴圈而達成者。 —般而言，溫度的下降係以非常緩慢的速率即約l〇C/min速 率降溫。在結晶反應期間，攪拌器轉速維持在320 rpm。 當溫度達到160°C，再次打開加熱器以進一步避免該溫度的 φ 降低。在溫度達到160°C後，進行去壓過程以將該反應器 壓力達至約100 psi。在此溫度的去壓將不會導致明顯的 PTA產物損失，但是僅有添加用以建構壓力的氫氣將被釋 出。 熱過濾：用以自對苯二曱酸的水性漿液移除對曱苯曱 酸的熱過濾係使用一 Sparkler過濾單元進行者。氮氡首先經 過此過渡單元並且使該過濾單元壓力維持在約80 pSig。隨 後將該反應器内容物通過轉移線轉移至該過濾單元。將該 反應器内容物連續地饋送，然而該過濾單元内的壓力藉由Psig. In a π hydrogen reactor, for example, a nitrogen pressure in the reactor is maintained in the reactor to fix a cooling loop of a catalyst containing a hydrogenation catalyst. Hydrogenation reaction: hydrogenation of CTA to convert the main impurity p-hydroxybenzaldehyde (4-CBA) to Pt〇luic aicd system at a temperature of 285 ° C, and the pressure of the reactor is maintained at 12 〇〇 psig, That is, the water pressure is exceeded to maintain the liquid phase and a suitable hydrogen supply is ensured. The hydrogenation reaction is carried out at different time intervals of φ, supplied with a hydrogen supply, and maintained at a constant pressure when the pressure is lowered and the water pressure is reached. Crystallization: After the end of the hydrogenation reaction, the hydrogenation reactor is turned off and the temperature of the reactor is circulated to the cooling reactor disposed in the hydrogenation reactor or disposed therein by cooling water having a temperature of about 10 - 15 °C. Loop back to the circle. In general, the temperature drop is cooled at a very slow rate, i.e., about 1 〇 C/min. The stirrer speed was maintained at 320 rpm during the crystallization reaction. When the temperature reached 160 ° C, the heater was turned on again to further avoid a decrease in φ of the temperature. After the temperature reached 160 ° C, a depressurization process was performed to bring the reactor pressure to about 100 psi. Depressurization at this temperature will not result in significant PTA product loss, but only the hydrogen added to build the pressure will be released. Hot Filtration: A thermal filtration system for the removal of p-benzoic acid from an aqueous slurry of terephthalic acid using a Sparkler filtration unit. Nitrogen enthalpy first passes through this transition unit and maintains the filtration unit pressure at about 80 pSig. The reactor contents are then transferred to the filtration unit via a transfer line. The reactor contents are continuously fed, however the pressure within the filter unit is
13 1359133 . 缓慢地控制加氫反應益的排放閥（drajn vaive )以維持在8〇 psig。該過濾單元溫度維持在約14〇_16〇〇c並且轉移線溫 度維持在約180-200DC。 以及熱洗滌：於加氫反應器内將大約6公升去離子水加 熱至160°C。160°C以及壓力約1〇〇 psig的熱水饋送至含有 該過濾糕狀物之該過濾單元。熱水連續地饋送至該過濾單 元，然而過濾單元内的壓力藉由緩慢地控制反應器的排放 闕以維持在80 psig。同樣的在洗滌過程中，轉移線的溫度 春維持在約180 - 200°C。 在洗滌過程後，所獲得該過濾糕狀物可自該過濾單元 依需要以及/或是被乾燥而移除。 在下列描述中，將敘述最佳化主要製備步驟以製備具 說明書所稱PTA純度的可能性。 加氫反應條件的最佳化：出現於CTA中的主要雜質係 對羥基苯甲醛（4-CBA)。4-CBA因聚合過程之熱不穩定性 •導致聚合物產生所不欲的呈色結果。因此用以還原4-CBA 的參數已被研讀。 第一圖表示於本發明中所獲得五批次的對苯二甲酸結 果，其係藉由變化反應以將4-CBA的含量從2500 ppm (off-spec)降低至小於25 ppin(on_spee)。 於batch-1以及batch-2中的加氫反應分別係在溫度 285°C以及壓力12〇〇 psig下分別進行4小時以及6小時。此分 析顯示於此兩批的加氫反應進行不完全。於所得pTA内出 現4-CBA内容物個別係5〇〇 ppm以及約6〇ppm。Kbatch_2 14 .. ⑧ 1359133 中4-CBA内容物明顯減少並伴隨反應時間增加2小時，但是 此内容物仍然未達參數。batch-3中的加氫反應係在溫度 285°C以及壓力1200 psig下分別進行8小時。此分析顯示於 此批的加氫反應進行完全。於所得pTA内出現4-CBA内容 物僅係5 ppm。batch-4、batch-5以及batch-5a中的加氫反應 係在相似batch-3的條件進行以確認獲得最佳參數。此分析 分別顯示這些批次的4-CBA内容物為5.2，6.8以及5.1 ppm。進一步言之’其可能以額外實驗證明，在壓力11〇〇 psi下加氫反應進行的不完全，並且4_CBA内容物含量高於 25 ppm。相似的結果可在溫度在26〇_32〇。(：之外而獲得。 熱過濾條件的最佳化：進一步於CTA内的主要雜質係 對曱苯甲酸。對甲苯曱酸作為聚合反應終止劑並且減緩聚 合反應速率’以及減少聚合物的平均分子量。第二圖表示 熱過濾實驗的結果，其係利用上述本發明方法進行不同批 的製備。 於batch-6 ’所獲得pta無需熱過濾並且對甲苯曱酸含 罝大約2200 ppm。 batch-6内的轉移線並未被加熱。於 batch-7，藉由熱過渡獲得pta並且對甲苯甲酸含量大約。 於batch-7轉移線的溫度大約丨〇〇〇c。此分析表示熱過濾並不 成功並且部分對甲笨甲酸隨著PTA_同結晶。Batch_8以及 batch-9於相似的方法進行除了轉移線的溫度增加至 220°C。此分析顯示在熱過濾後對曱苯曱酸的含量分別降低 至160以及220 ppm。這些結果顯示修正的熱過濾係成功的 並且對甲苯曱酸的含量可大量降低。 1359133 « 熱洗滌條件的最佳化：與說明書中的PTA，對甲苯甲 酸的含量應該少於150 ppm。因此PTA糕狀物以熱水洗滌而 進一步減少對f苯曱酸含量。第三圖顯示熱過濾以及熱洗 滌實驗的結果於本發明方法中進行數批。在熱過濾以及熱 洗滌後於batch-8中之對甲苯甲酸含量分別係16〇 ppm以及 約97 ppm。相似的，於batch-9中之對甲苯甲酸含量在熱過 遽以及熱洗蘇後分別係200 ppm以及98 ppm。更多實驗同時 進行熱過瀘、以及熱洗滌，並且所得PTA分析顯示對曱苯甲 • 酸含量總是符合參數(<150 ppm)。 金屬雜質的移除：在純化對苯二甲酸的聚合反應期間 以銻為催化劑產生有毒金屬雜質。於純化對笨二甲酸中， 王體金屬各里應少於10 ppm。第四圖顯示於本發明方法 中使用不同金屬材料（稱為SS-316、Duplex-SS以及鈦）作 為催化劑筐所獲得數批次的金屬分析。所獲得pTA顯示非 常高總量金屬含量以及SS-316，SS_316並不合適作為實施 •粗製對苯二甲酸的純化方法之建構材料。總量金屬含量使 用鈦符合參數並且duplex-SS作為催化劑筐的材質。 有色雜質的移除：出現於CTA中的有色雜質降低聚酯 的炫點以及/或是導致聚酯的染色。事實上粗製對苯二 甲酸所内含的一些雜質係呈色前驅物。因此，可=驗根據 本發明批次過程所製備PTA上的已知以及潛在有色雜質。 二種光學特性，delta Y、b-value以及ApHA色值可被查 驗。一delta Y值大於10 ' b_vakie大於2 5以及ApHA色值: 於1〇(_指出樣品被嚴重污染並且無法為市場所接受。13 1359133. The discharge valve (drajn vaive) of the hydrogenation reaction is slowly controlled to maintain 8 psig. The filter unit temperature was maintained at about 14 〇 16 〇〇 c and the transfer line temperature was maintained at about 180-200 VDC. And hot wash: about 6 liters of deionized water was heated to 160 ° C in the hydrogenation reactor. Hot water at 160 ° C and a pressure of about 1 psig is fed to the filtration unit containing the filtered cake. Hot water was continuously fed to the filtration unit, however the pressure in the filtration unit was maintained at 80 psig by slowly controlling the discharge of the reactor. Similarly, during the washing process, the temperature of the transfer line is maintained at about 180 - 200 ° C. After the washing process, the filtered cake obtained can be removed from the filtration unit as needed and/or dried. In the following description, the main preparation steps will be described to optimize the possibility of preparing the purity of the PTA as described in the specification. Optimization of hydrogenation reaction conditions: The main impurity present in CTA is p-hydroxybenzaldehyde (4-CBA). The thermal instability of 4-CBA due to the polymerization process • Causes the polymer to produce unwanted coloration results. Therefore, the parameters used to restore 4-CBA have been studied. The first panel shows the five batches of terephthalic acid obtained in the present invention by varying the reaction to reduce the 4-CBA content from 2500 ppm (off-spec) to less than 25 ppin (on_spee). The hydrogenation reactions in batch-1 and batch-2 were carried out at a temperature of 285 ° C and a pressure of 12 psig for 4 hours and 6 hours, respectively. This analysis showed that the hydrogenation reactions in the two batches were incomplete. The 4-CBA content was found to be 5 〇〇 ppm and about 6 〇 ppm in the resulting pTA. The content of 4-CBA in Kbatch_2 14 .. 8 1359133 was significantly reduced and the reaction time was increased by 2 hours, but the contents were still below the parameters. The hydrogenation reaction in batch-3 was carried out for 8 hours at a temperature of 285 ° C and a pressure of 1200 psig, respectively. This analysis shows that the hydrogenation reaction in this batch is complete. The 4-CBA content appeared in the resulting pTA was only 5 ppm. The hydrogenation reactions in batch-4, batch-5, and batch-5a were carried out under conditions similar to batch-3 to confirm that the optimum parameters were obtained. This analysis shows that the 4-CBA content of these batches is 5.2, 6.8, and 5.1 ppm, respectively. Further, it may be demonstrated by additional experiments that the hydrogenation reaction is incomplete at a pressure of 11 psi and that the 4_CBA content is above 25 ppm. Similar results can be found at temperatures between 26 〇 and 32 〇. (: obtained externally. Optimization of hot filtration conditions: further major impurities in CTA are p-benzoic acid. p-Toluic acid as a polymerization terminator and slow down the polymerization rate' and reduce the average molecular weight of the polymer The second figure shows the results of the hot filtration experiment, which was prepared in different batches by the method of the present invention described above. The pta obtained in batch-6' does not require thermal filtration and contains about 2200 ppm of p-toluic acid. The transfer line was not heated. In batch-7, pta was obtained by thermal transition and the p-toluic acid content was approximately. The temperature of the batch-7 transfer line was approximately 丨〇〇〇c. This analysis indicates that the thermal filtration was not successful and Part of the p-formic acid with PTA_ is crystallized. Batch_8 and batch-9 were carried out in a similar manner except that the temperature of the transfer line was increased to 220 ° C. This analysis showed that the content of indomethacin decreased after hot filtration to 160 and 220 ppm. These results show that the modified hot filter system is successful and the content of toluene decanoic acid can be greatly reduced. 1359133 « Optimization of hot wash conditions: with instructions The PTA, p-toluic acid content should be less than 150 ppm. Therefore, the PTA cake is washed with hot water to further reduce the content of f-benzoic acid. The third figure shows the results of the thermal filtration and thermal washing experiments in the method of the present invention. Several batches were carried out. The content of p-toluic acid in batch-8 after hot filtration and hot washing was 16 〇ppm and about 97 ppm, respectively. Similarly, the p-toluic acid content in batch-9 was hot and hot. After washing, the cells were 200 ppm and 98 ppm respectively. More experiments were performed simultaneously with thermal enthalpy and thermal washing, and the resulting PTA analysis showed that the phthalic acid content always met the parameter (<150 ppm). Removal: toxic metal impurities are produced by using ruthenium as a catalyst during the polymerization of purified terephthalic acid. In the purification of p-dicarboxylic acid, the king metal should be less than 10 ppm. The fourth figure is shown in the method of the present invention. Several batches of metal analysis were obtained using different metal materials (referred to as SS-316, Duplex-SS, and titanium) as catalyst baskets. The obtained pTA showed very high total metal content and SS-316, SS_316 was not suitable Implementation material for the purification method of crude terephthalic acid. The total metal content is titanium using the parameters and duplex-SS is used as the material of the catalyst basket. Removal of colored impurities: Colored impurities appearing in CTA reduce the polyester Point and/or cause dyeing of the polyester. In fact, some of the impurities contained in the crude terephthalic acid are color precursors. Therefore, it is possible to test the known and potential on the PTA prepared according to the batch process of the present invention. Colored impurities. Two optical properties, delta Y, b-value and ApHA color values can be checked. A delta Y value greater than 10 'b_vakie is greater than 2 5 and ApHA color value: at 1〇 (_ indicates that the sample is heavily contaminated and cannot be accepted by the market.
16 1359133 第五圖顯示其光學特性的結果，其係使用不同材料作為催 化劑筐所獲得數批PTA之delta Y、b-value以及APHA色 值。準此，於加氫反應中所使用催化劑筐的合金為duplex。 催化劑筐的能力係大於加氫反應中所使用的催化劑量。因 此，在高壓以及攪拌下，催化劑丸（pellets)於催化劑筐 内移動並且一些被擠碎並且將顏色導入產物。因此，PTA 產物的顏色被影響。在duplex包裝籃中，一些惰性材質被 使用來填充催化劑筐内剩餘的空間以致於催化劑丸被固定 並且不可移動。 揭露於先前描述中、申請專利範圍的技術特徵以及/或 是配合圖式均分別或以任何組合型態，用以了解本發明不 同的實施態樣。 【圖式簡單說明】 第一圖係繪示利用本發明的方法於不同氫化時間所得 對羥基苯甲醛内容物的比較。 第二圖係繪示於本發明方法中之熱過濾後對甲苯甲酸 内容物的比較。 第三圖係繪示於本發明方法中之熱洗滌後對甲苯曱酸 内容物的比較。 第四圖係繪示於本發明方法中使用不同金屬内容物作 為催化劑催化劑筐的材料之比較。 第五圖係繪示藉由本發明方法所獲得純化對苯二甲酸 所具有的顏色特性之比較。 1359133 【主要元件符號說明】16 1359133 The fifth plot shows the results of its optical properties using different materials as the catalyst basket for the delta Y, b-value and APHA color values of several batches of PTA. Accordingly, the alloy of the catalyst basket used in the hydrogenation reaction is duplex. The capacity of the catalyst basket is greater than the amount of catalyst used in the hydrogenation reaction. Thus, under high pressure and agitation, the pellets move within the catalyst basket and some are crushed and the color is introduced into the product. Therefore, the color of the PTA product is affected. In a duplex basket, some inert material is used to fill the remaining space in the catalyst basket so that the catalyst pellets are fixed and immovable. The technical features disclosed in the foregoing description, the scope of the patent application, and/or the combination of the drawings are respectively used in the form of a combination or a combination thereof to understand the different embodiments of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS The first figure shows a comparison of the contents of p-hydroxybenzaldehyde obtained by the method of the present invention at different hydrogenation times. The second figure is a comparison of the contents of p-toluic acid after hot filtration in the process of the present invention. The third figure is a comparison of the contents of toluene decanoic acid after hot washing in the process of the present invention. The fourth figure is a comparison of the materials used in the process of the invention using different metal contents as catalyst catalyst baskets. The fifth figure shows a comparison of the color characteristics of purified terephthalic acid obtained by the process of the present invention. 1359133 [Description of main component symbols]