WO2010040251A1

WO2010040251A1 - Process and apparatus for preparing terephthalic acid by air oxidation of para-xylene

Info

Publication number: WO2010040251A1
Application number: PCT/CN2008/001764
Authority: WO
Inventors: 郭灿城; 罗伟平; 周然飞; 李国友; 龚天保; 刘强
Original assignee: 湖南大学; 北京华博致远化工电子研究所
Priority date: 2008-10-08
Filing date: 2008-10-20
Publication date: 2010-04-15
Also published as: CN101362687B; CN101362687A

Abstract

Disclosed are a process and an apparatus for preparing terephthalic acid by air oxidation of para-xylene. Said process is: in a reaction system with oxidation reactor and crystallizer connecting in series, para-xylene with dissolved metalloporphyrins or mixed catalyst of metalloporphyrins and metal salt, and air, oxygen-poor air, oxygen-rich air or carbon-dioxide-containing air are fed into the oxidation reactor which stay in the reactor for 70-180 minutes at 140-200 °C. The oxidation mixture crystallizes by flooding or being pumped into crystallizer. Para-xylene, para-toluic acid and para-methyl benzyl alcohol obtained by separation are fed into oxidation reactor, mixed with para-xylene containing metalloporphyrins catalyst for the second oxidation, and the crystals are purified to obtain purified terephthalic acid. In the present invention para-xylene is oxidized directly into terephthalic acid, the energy consumption is low, the production efficiency is high, and the conversion of para-xylene and the yield of terephthalic acid are above 95%.

Description

N2008/001764 空气氧化对二甲苯制备对苯二甲酸的方法和设备技术领域 N2008/001764 Method and apparatus for preparing terephthalic acid by air oxidation of p-xylene

本发明涉及一种对二甲苯空气氧化制备对苯二甲酸的方法和设备，尤其是涉及一种金属卟啉或者金属卟啉与金属盐为催化剂的对二甲苯空气氧化制备对苯二甲酸的方法和设备。 The invention relates to a method and a device for preparing terephthalic acid by air oxidation of p-xylene, in particular to a method for preparing terephthalic acid by air oxidation of p-xylene by using metal porphyrin or metal porphyrin and metal salt as catalyst And equipment.

技术背景 technical background

对苯二甲酸是聚酯工业的主要原料。目前，工业上主要由对二甲苯液相催化氧化生产对苯二甲酸。该方法是以醋酸为溶剂，醋酸钴、醋酸锰为催化剂，溴化物等为促进剂，在 180〜200°C、 14〜li5 MPa下，用空气氧化对二甲苯。对二甲苯的转化率和产物中对苯二甲酸含量都达到 95%以上。但该方法使用醋酸作溶剂，含量为 80%，对二甲苯的含量小于 20%，生产效率低，能耗大。另外，大量醋酸溶剂和溴化物的使用，设备腐蚀和环境污染严重。科学技术界一直在致力于对苯二甲酸制备新方法的研究。近年来，采用金属卟啉仿生催化空气氧化对二甲苯制备对苯二甲酸的技术已经报道。专利 CN1775725A公开了在醋酸为溶剂的钴 /锰 /溴体系中加入金属卟啉提高对二甲苯空气氧化速率的方法。该技术方案能在一定程度上降低能耗，提高生产效率，但作为溶剂的醋酸含量仍高达 80%，溴化物的量也没有减少，没有从根本上降低能耗和提高生产效率，也没有解决设备腐蚀和环境污染问题。专利 CN1333200公开了由金属卟啉或金属卟啉与金属盐催化空气氧化二甲苯的工该工艺不使用腐蚀性的醋酸溶剂和溴化物，避免了腐蚀和环境污染问题，但氧化产物为甲基苯甲醛、甲基苯甲醇和甲基苯甲酸而不是对苯二甲酸。专利 CN1453259公开了一种由金属卟啉或金属卟啉与金属盐催化芳香甲基苯被空气含二氧化碳空气直接氧化成为相应芳香羧酸的工艺。该工艺不使用腐蚀性的醋酸溶剂和溴化物，,可以避免腐蚀和环境污染问题，当原料为对二甲苯时，转化率可达到 85%，氧化产物中对苯二甲酸含量可达到 70%。但该专利公开的反应工艺只适合间隙反应过程，不适合连续化工业生产，且对二甲苯转化率和产物中对苯二甲酸含量不能满足工业生产要求。到目前为止，对于金属卟啉或金属卟啉与金属盐催化对二甲苯体系还没有通过连续反应过程直接从对二甲苯反应高产率得到对苯二甲酸的报道。 Terephthalic acid is the main raw material for the polyester industry. At present, industrially, terephthalic acid is mainly produced by liquid phase catalytic oxidation of p-xylene. In the method, acetic acid is used as a solvent, cobalt acetate, manganese acetate as a catalyst, bromide or the like as a promoter, and p-xylene is oxidized by air at 180 to 200 ° C and 14 to li 5 MPa. Both the conversion of p-xylene and the content of terephthalic acid in the product reached more than 95%. However, this method uses acetic acid as a solvent, the content is 80%, the content of p-xylene is less than 20%, the production efficiency is low, and the energy consumption is large. In addition, the use of a large amount of acetic acid solvent and bromide, equipment corrosion and environmental pollution is serious. The scientific and technological community has been working on new methods for the preparation of terephthalic acid. In recent years, techniques for the catalytic oxidation of p-xylene to terephthalic acid by metal porphyrin biocatalytic catalysis have been reported. Patent CN1775725A discloses a method for increasing the rate of air oxidation of p-xylene by adding a metal porphyrin to a cobalt/manganese/bromine system in which acetic acid is a solvent. The technical solution can reduce energy consumption and improve production efficiency to a certain extent, but the acetic acid content as a solvent is still as high as 80%, the amount of bromide is not reduced, the energy consumption is not fundamentally reduced, and the production efficiency is not solved. Equipment corrosion and environmental pollution problems. Patent CN1333200 discloses the catalytic oxidation of xylene by metal porphyrin or metalloporphyrin and metal salt. The process does not use corrosive acetic acid solvent and bromide to avoid corrosion and environmental pollution problems, but the oxidation product is methylbenzene. Formaldehyde, methyl benzyl alcohol and methyl benzoic acid instead of terephthalic acid. Patent CN1453259 discloses a process for the direct oxidation of aromatic methylbenzene to a corresponding aromatic carboxylic acid by air-containing carbon dioxide air catalyzed by a metal porphyrin or a metal porphyrin and a metal salt. This process does not use corrosive acetic acid solvents and bromide to avoid corrosion and ring In the case of environmental pollution, when the raw material is para-xylene, the conversion rate can reach 85%, and the content of terephthalic acid in the oxidation product can reach 70%. However, the reaction process disclosed in this patent is only suitable for the interstitial reaction process, and is not suitable for continuous industrial production, and the conversion of p-xylene and the content of terephthalic acid in the product cannot meet the requirements of industrial production. So far, there have been no reports on the high yield of terephthalic acid from the p-xylene reaction by the metal porphyrin or metal porphyrin and the metal salt catalyzed p-xylene system through a continuous reaction process.

发明内容 Summary of the invention

本发明的目的是提供一种以金属卟啉为催化剂，以空气、贫氧空气、富氧空气或者含二氧化碳的空气作氧化剂，对二甲苯通过连续氧化过程高转化率、高收率得到对苯二甲酸的方法和设备。 The object of the present invention is to provide a metal porphyrin as a catalyst, air, oxygen-poor air, oxygen-enriched air or carbon dioxide-containing air as an oxidant, and p-xylene can obtain benzene by high conversion rate and high yield through continuous oxidation process. Method and apparatus for dicarboxylic acid.

氧化反应分为对二甲苯初次氧化和初次氧化产物对甲基苯甲酸和对甲基苯甲醇混合物的二次氧化两个氧化过程。两次氧化在同一反应器循环完成并构成连续氧化过程。实现该制备过程的设备由氧化反应器和结晶分离器两部分组成，为了提高氧化效率，氧化反应器由 1个或多个搅拌反应釜构成，氧化反应釜之间或者氧化反应釜与结晶分离罐之间除了通过管道串联以外，还连接有固体泵。从氧化反应器出来的对苯二甲酸在结晶分离器中与对甲基苯甲酸和对甲基苯甲醇进行分离。经结晶分离过程，氧化产物混合液中的对苯二甲酸以结晶状态与对二甲苯、对甲基苯甲酸和对甲基苯甲醇分离。对二甲苯、对甲基苯甲酸和对甲基苯甲醇泵入氧化反应器，与含有金属卟啉催化剂的对二甲苯混合后进行二次氧化，结晶产物经纯化后得到寸苯二甲酸。 The oxidation reaction is divided into two oxidation processes: primary oxidation of p-xylene and secondary oxidation of the primary oxidation product p-methylbenzoic acid and p-methylbenzyl alcohol mixture. The two oxidations are completed in the same reactor cycle and constitute a continuous oxidation process. The apparatus for realizing the preparation process is composed of an oxidation reactor and a crystallization separator. In order to improve the oxidation efficiency, the oxidation reactor is composed of one or more stirred reactors, between the oxidation reactors or the oxidation reactor and the crystal separation tank. In addition to being connected in series by a pipe, a solid pump is connected. The terephthalic acid from the oxidation reactor is separated from p-methylbenzoic acid and p-methylbenzyl alcohol in a crystallizer. Through the crystallization separation process, terephthalic acid in the oxidation product mixture is separated from para-xylene, p-methylbenzoic acid and p-methylbenzyl alcohol in a crystalline state. Para-xylene, p-methylbenzoic acid and p-methylbenzyl alcohol are pumped into an oxidation reactor, mixed with p-xylene containing a metalloporphyrin catalyst, and then subjected to secondary oxidation, and the crystallized product is purified to obtain an indigophthalic acid.

本发明的技术方案是：在由 1 - 4个带有搅拌装置的反应釜串联组成的氧化反应器和结晶分离器串联的反应***中，向氧化反应器连续通入溶有卟啉催化剂的对二甲苯及 8 atm-20 atm的空气或者富氧或贫氧空气或者含二氧化碳的空卟啉与金属盐按浓度比 1 : 20- 100混合的催化剂，在温度 140°C- 200°C条件下，对二甲苯在氧化反应器中停留 70分钟- 180 分钟，氧化反应混合物经溢流或者泵入与氧化反应***温度和压力相同的结晶器，或者泵入 l atm和 120 °C-160 °C的结晶器中进行常压恒温结晶，经分离得到的对二甲苯、对甲基苯甲酸和对甲基苯甲醇通入氧化反应器与含有金属卟啉催化剂的对二甲苯混合进入二次氧化，结晶经纯化得到精对苯二甲酸。 According to the technical solution of the present invention, in a reaction system in which an oxidation reactor composed of 1-4 reactors with a stirring device and a crystallization reactor are connected in series, a pair of porphyrin catalysts are continuously introduced into the oxidation reactor. Xylene and 8 atm-20 atm air or oxygen-rich or oxygen-depleted air or carbon dioxide-containing air The porphyrin and the metal salt are mixed at a concentration ratio of 1:20-100, and the p-xylene is allowed to stand in the oxidation reactor for 70 minutes to 180 minutes at a temperature of 140 ° C to 200 ° C, and the oxidation reaction mixture is overflowed. Or pump the crystallizer with the same temperature and pressure as the oxidation reaction system, or pump it into the crystallizer of l atm and 120 °C-160 °C for constant temperature constant temperature crystallization, and the separated p-xylene and p-methylbenzene. Formic acid and p-methylbenzyl alcohol are fed into an oxidation reactor and mixed with p-xylene containing a metal porphyrin catalyst to undergo secondary oxidation, and the crystals are purified to obtain purified terephthalic acid.

通式（ I )的金属原子 M为过渡金属原子 Co或 Cu、 Ni、 Zn、 Ru;通式（ II ) 中的金属原子 M为 Fe或 Mn、 Cr; 通式（III ) 中的金属原子， 1^₂为？6或 Mn、 Cr_;通式（ II )中的配位基 X为乙酸或乙酰丙酮、卤素、酸根负离子；通式（ I ) 和（II ) '和（III) 中取代基 Ri，，为氢或烃基、烷氧基、羟基、卤素、胺基、氨基、硝基。 The metal atom M of the formula (I) is a transition metal atom Co or Cu, Ni, Zn, Ru; the metal atom M in the formula (II) is Fe or Mn, Cr; a metal atom in the formula (III), 1^ ₂ is? 6 or Mn, Cr _; the ligand X in the formula (II) is acetic acid or acetylacetone, halogen, acid anion; the substituents Ri, in the formula (I) and (II) ' and (III) are hydrogen Or a hydrocarbyl group, an alkoxy group, a hydroxyl group, a halogen, an amine group, an amino group, a nitro group.

( II ) (II)

上述技术方案中与金属卟啉构成复合催化剂的金属盐为过渡金属 Cu或 Zn、 Fe、 Co、 Mn、 Cr、 Ni的盐。 The metal salt constituting the composite catalyst with the metal porphyrin in the above technical solution is a transition metal Cu or a salt of Zn, Fe, Co, Mn, Cr or Ni.

本发明优选的技术方案为：氧化反应器连续通入溶有 5 PPM-10 PPM金属卟啉催化剂的对二甲苯及 10 atm- 12 atm的空气，在温度 170°C- 19CTC条件下，对二甲苯在氧化反应器中停留 100 分钟- 120 分钟，结晶分离器温度为 145°C -160°C , 压力为***压力或者结晶分离器温度为 130°C- 140°C，.压力为 1 atm。 A preferred technical solution of the present invention is: the oxidation reactor is continuously fed into a paraxylene solution of 5 PPM-10 PPM metal porphyrin catalyst and air of 10 atm-12 atm, at a temperature of 170 ° C - 19 CTC, The toluene is held in the oxidation reactor for 100 minutes - 120 minutes, the crystallization separator temperature is 145 ° C - 160 ° C, the pressure is the system pressure or the crystallization separator temperature is 130 ° C - 140 ° C, and the pressure is 1 atm.

丰发明的技术方案为也可优选为：氧化反应器连续通入溶有 3 PPM-8 PPM 金属卟啉与 60 PPM-200 PPM金属盐混合催化剂的对二甲苯及 10 atra-12 atm 的空气，在温度 160°C- 18CTC条件下，对二甲苯在氧化反应器中停留 100分钟 N2008/001764 The technical solution of the invention is also preferably: the oxidation reactor is continuously fed with p-xylene and 10 atra-12 atm air dissolved in a mixed catalyst of 3 PPM-8 PPM metal porphyrin and 60 PPM-200 PPM metal salt. P-xylene stays in the oxidation reactor for 100 minutes at a temperature of 160 ° C - 18 CTC N2008/001764

-120 分钟，结晶分离器温度为 145°C_16(TC，压力为***压力或者结晶分离器温度为 130 °C- 140 °C，压力为 1 atmc -120 minutes, crystallization separator temperature is 145 ° C_16 (TC, pressure is system pressure or crystallizer temperature is 130 °C - 140 °C, pressure is 1 atmc

本发明选用的氧化反应器包括氧化反应器和结晶分离器构成的***，其中氧化反应器***为串联的 1-4个带搅拌装置的反应釜，搅拌装置可以是机械搅拌，电动搅拌，磁力搅拌或者超重力搅拌，结晶分离器为带有恒温控制装置的液固分离罐，氧化反应釜之间或者氧化反应釜与结晶分离罐之间除了通过管道串联以外，还连接有固体泵。 The oxidation reactor selected by the invention comprises a system consisting of an oxidation reactor and a crystallizer, wherein the oxidation reactor system is a reaction kettle with 1-4 stirring devices in series, and the stirring device can be mechanical stirring, electric stirring, magnetic stirring. Or supergravity stirring, the crystallization separator is a liquid-solid separation tank with a constant temperature control device, and a solid pump is connected between the oxidation reaction kettles or between the oxidation reaction reactor and the crystallization separation tank, in addition to being connected in series through a pipeline.

本发明是根据金属卟啉能催化空气氧化对二甲苯成对甲基苯甲酸和对甲基苯甲醇，也能催化空气氧化对甲基苯甲酸和对甲基苯甲醇成对苯二甲酸的特点，设计在金属卟啉催化对二甲苯氧化期间引入结晶过程，氧化产物混合液中的对甲基苯甲酸和对甲基苯甲醇进入氧化反应器与含有金属卟啉催化剂的对二甲苯混合后二次反应，氧化产物对苯二甲酸在结晶分离器中结晶分离。该方法中对二甲苯转化率和对苯二甲酸收率都达到 95%以上。 The invention is characterized in that the metal porphyrin catalyzes the air oxidation of p-xylene-p-methylbenzoic acid and p-methylbenzyl alcohol, and also catalyzes the oxidation of p-methylbenzoic acid and p-methylbenzyl alcohol to terephthalic acid. Designed to introduce a crystallization process during the oxidation of p-xylene by a metal porphyrin catalyze, mixing p-methylbenzoic acid and p-methylbenzyl alcohol in the oxidation product mixture into an oxidation reactor and mixing p-xylene containing a metal porphyrin catalyst. In the secondary reaction, the oxidation product terephthalic acid is crystallized and separated in a crystallizer. In this method, the conversion of p-xylene and the yield of terephthalic acid all reached 95% or more.

具体实施方式 , detailed description ,

以下结合实施例对本发明作进一步说明，但不得解释为对本发明保护范围的限制。， The invention is further illustrated by the following examples, but is not to be construed as limiting the scope of the invention. ,

实施例 1 : Example 1

反应设备包括 1个带机械搅拌和空气分布器的反应釜和 1个结晶罐，氧化反应釜与结晶分离罐之间同时通过管道和固体泵连接。生产工艺流程为：在 180 °C下通入溶有 2 PPM结构式（ I ) 的金属卟啉， R₂= R H, M= CO 的对二甲苯，将 18 atm经气体分布器的空气通入搅拌反应釜的底部，控制对二甲苯流速使停留时间为 100分钟，控制空气流速使尾氧含量不超过 6%。搅拌反应釜上部的反应液溢流通入结晶分离罐，搅拌反应^下部的固体悬浮液经泵进入结晶分离罐。维持结晶分离罐 155°C和 1 atm。对二甲酸从反应混合物中结晶出来并与对甲基苯甲酸、对甲基苯甲醇和对二甲苯分离。对甲基苯甲酸、对甲基苯甲醇和对二甲苯与含有金属卟啉催化剂的对二甲苯混合后通入搅拌反应釜进行二次氧化。上述过程连续循环。对二甲苯转化率为 98%，对苯二甲酸收率为 95%。 The reaction apparatus comprises a reaction vessel with mechanical agitation and an air distributor and a crystallization tank, and the oxidation reactor and the crystallization separation tank are simultaneously connected by a pipe and a solid pump. The production process is as follows: a metal porphyrin dissolved in 2 PPM of formula (I), a paraxylene of R ₂ = RH, M=CO, and a gas of 18 atm passing through the gas distributor are introduced at 180 °C. At the bottom of the reactor, the paraxylene flow rate was controlled so that the residence time was 100 minutes, and the air flow rate was controlled so that the tail oxygen content did not exceed 6%. The reaction liquid in the upper part of the stirred reactor overflows into the crystallization separation tank, and the solid suspension in the lower part of the reaction is stirred and pumped into the crystallization point. Off the can. The crystallization separation tank was maintained at 155 ° C and 1 atm. The dicarboxylic acid was crystallized from the reaction mixture and separated from p-methylbenzoic acid, p-methylbenzyl alcohol and p-xylene. The p-methylbenzoic acid, p-methylbenzyl alcohol and p-xylene are mixed with p-xylene containing a metal porphyrin catalyst, and then passed through a stirred reaction vessel for secondary oxidation. The above process is continuously cycled. The p-xylene conversion was 98% and the terephthalic acid yield was 95%.

实施例 2: Example 2:

反应设备包括 2个带电动搅拌和空气分布器的反应釜和 1个结晶罐，氧化反应釜与结晶分离罐之间同时通过管道和固体泵连接。生产工艺流程为：在 185 °C下通入溶有 8 PPM结构式（II ) 的金属卟啉， R,= C¾， R₂= H, M= Fe，配位基 X为 CI的对二甲苯，将 16 atm含氧 18%的贫氧空气经气体分布器后通入搅拌反应釜 1的底部，搅拌反应釜 1上部的反应液通过溢流通入搅拌反应釜 2 , 搅拌反应釜 1下部的悬浮反应液通过泵泵入搅拌反应釜 2，在搅拌反应釜 2 中通入含氧 18%的贫氧空气。控制对二甲苯流速使停留时间为 120分钟。控制空气流速使尾氧含量不超过 6%。反应器 2上部和下部的反应液分别经溢流和泵进入结晶分离罐。维持结晶分离罐 14(TC和 1 atm。对苯二甲酸从反应混合物中结晶出来并与对甲基苯甲酸、对甲基苹甲醇和对二甲苯分离。对甲基苯甲酸、对甲基苯甲醇和对二甲苯与含有金属卟啉催化剂的对二甲苯混合后通入搅拌反应釜 1进行二次氧化。上述过程连续循环。对二甲苯转化率为 9%，对苯二甲酸收率为 97%。 , , The reaction apparatus comprises two reaction kettles with an electric stirring and an air distributor and a crystallizing tank, and the oxidation reactor and the crystal separation tank are simultaneously connected by a pipe and a solid pump. The production process is as follows: a metal porphyrin dissolved in 8 PPM of formula (II) is introduced at 185 ° C, R, = C3⁄4, R ₂ = H, M = Fe, and the ligand X is CI paraxylene. 16 atm of oxygen-containing 18% oxygen-lean air is passed through the gas distributor and then passed to the bottom of the stirred reactor 1, and the reaction liquid in the upper portion of the stirred tank 1 is stirred and passed through the overflow reactor 2, and the suspension reaction in the lower portion of the reactor 1 is stirred. The liquid was pumped into the stirred reactor 2 by means of a pump, and 18% of oxygen-poor air containing oxygen was introduced into the stirred reactor 2. The paraxylene flow rate was controlled so that the residence time was 120 minutes. The air flow rate is controlled so that the tail oxygen content does not exceed 6%. The reaction liquids at the upper and lower portions of the reactor 2 are respectively passed through an overflow and a pump into the crystallization separation tank. Maintain crystallization separation tank 14 (TC and 1 atm. Terephthalic acid crystallized from the reaction mixture and separated from p-methylbenzoic acid, p-methyl ethmethanol and p-xylene. p-methylbenzoic acid, p-toluene Methanol and p-xylene are mixed with p-xylene containing a metal porphyrin catalyst and then passed to a stirred reactor 1 for secondary oxidation. The above process is continuously cycled. The conversion of p-xylene is 9%, and the yield of terephthalic acid is 97. %. , ,

实施例 3: Example 3:

反应设备包括 3个带磁力搅拌和空气分布器的反应釜和 1个结晶罐，氧化反应釜与结晶分离罐之间同时通过管道和固体泵连接。生产工艺流程为：在 195 °C下通入溶有 50 PPM结构式 ( III ) 的金属卟啉， R 0C¾， R₂: R₃二 H， M〗： M₂= n的对二甲苯，将 20 atm含氧 23%的富氧空气经气体分布器后通入搅拌反应釜 1的底部，反应器 2上部和下部的反应液分别经溢流和泵进入搅拌反应釜 2的底部，向搅拌反应器 2通入含氧 23%的富氧空气，搅拌反应器 2上部和下部的反应液分别经溢流和泵进入搅拌反应釜 3的底部，向搅拌反应器 3通入含氧 23% 的富氧空气。控制对二甲苯流速使停留时间为 70分钟，控制空气流速使尾氧含量不超过 5%。反应器 3上部和下部的反应液分别经溢流和泵进入结晶分离罐。维持结晶分离罐 16CTC和 1 atm。对苯二甲酸从反应混合物中结晶出来并与对甲基苯甲酸、对甲基苯甲醇和对二甲苯分离。对甲基苯甲酸、对甲基苯甲醇和对二甲苯与含有金属卟啉催化剂的对二甲苯混合后通入搅拌反应釜 1进行二次氧化。上述过程连续循环。对二甲苯转化率为 97%，对苯二甲酸收率为 95%。 The reaction apparatus comprises three reaction vessels with a magnetic stirring and an air distributor and a crystallizing tank, and the oxidation reactor and the crystal separation tank are simultaneously connected by a pipe and a solid pump. The production process is as follows: a metal porphyrin dissolved in 50 PPM of formula (III) is introduced at 195 °C, R 0C3⁄4, R ₂ : R ₃ di H, M: M ₂ = n p-xylene, 20 Atm 23% oxygen-enriched air is passed through a gas distributor and passed into a stirred reactor. At the bottom of 1, the reaction liquid in the upper part and the lower part of the reactor 2 is respectively overflowed and pumped into the bottom of the stirred reaction tank 2, and 23% oxygen-enriched air containing oxygen is introduced into the stirred reactor 2, and the upper and lower portions of the reactor 2 are stirred. The reaction liquid enters the bottom of the stirred reaction tank 3 through an overflow and a pump, respectively, and an oxygen-enriched air containing 23% of oxygen is supplied to the stirred reactor 3. The paraxylene flow rate was controlled so that the residence time was 70 minutes, and the air flow rate was controlled so that the tail oxygen content did not exceed 5%. The reaction liquids at the upper and lower portions of the reactor 3 are respectively passed through an overflow and a pump into a crystallization separation tank. The crystallization separation tanks 16CTC and 1 atm were maintained. Terephthalic acid crystallizes from the reaction mixture and is separated from p-methylbenzoic acid, p-methylbenzyl alcohol and p-xylene. The p-methylbenzoic acid, p-methylbenzyl alcohol and p-xylene are mixed with p-xylene containing a metal porphyrin catalyst, and then passed through a stirred reaction vessel 1 for secondary oxidation. The above process is continuously cycled. The p-xylene conversion was 97% and the terephthalic acid yield was 95%.

实施例 4: Example 4:

反应设备包括 1个带重力搅拌和空气分布器的反应釜和 1个结晶罐，氧化反应釜与结晶分离罐之间同时通过管道和固体泵连接。生产工艺流程为：在 200 °C下通入溶有 15 PPM结构式 (III) 的金属卟啉， Ri- CI , H H， M! = M₂ = Fe 的对二甲苯，将 10 atm含 3% C0₂的空气经气体分布器后通入搅拌反应釜的底部，控制对二甲苯流速使停留时间为 150分钟，控制空气流速使尾氧含量不超过 5%。搅拌反应釜上部和下部的反应液分别经溢流和泵进入结晶分离罐。结晶分离罐的温度和压力与氧化反应体系相同。对苯二甲酸从反应混合物中结晶出来并与对甲基苯甲酸、对甲基苯甲醇和对二甲苯分离。对甲基苯甲酸、对甲基苯甲醇和对二甲苯与含有金属卟啉催化剂的对二甲苯混合后通入搅拌反应釜 1 进行二次氧化。上述过程连续循环。对二苯转化率为 99%，对苯二甲酸收率为 97%。 The reaction apparatus comprises a reaction vessel with a gravity agitation and an air distributor and a crystallization tank, and the oxidation reactor and the crystallization separation tank are simultaneously connected by a pipe and a solid pump. The production process is as follows: a metal porphyrin dissolved in 15 PPM of formula (III), Ri- CI, HH, M! = M ₂ = Fe in p-xylene at a temperature of 200 °C, and 10 atm containing 3% C0 The air of ₂ is passed through the gas distributor to the bottom of the stirred reactor, the paraxylene flow rate is controlled so that the residence time is 150 minutes, and the air flow rate is controlled so that the tail oxygen content does not exceed 5%. The reaction liquids in the upper and lower portions of the stirred reactor were respectively passed through an overflow and a pump into a crystallization separation tank. The temperature and pressure of the crystallization separation tank are the same as those of the oxidation reaction system. Terephthalic acid crystallizes from the reaction mixture and is separated from p-methylbenzoic acid, p-methylbenzyl alcohol and p-xylene. The p-methylbenzoic acid, p-methylbenzyl alcohol and p-xylene are mixed with p-xylene containing a metal porphyrin catalyst, and then passed to a stirred reactor 1 for secondary oxidation. The above process is continuously cycled. The conversion of p-diphenyl was 99%, and the yield of terephthalic acid was 97%.

实施例 5: Example 5

反应设备包括 3个带电动搅拌和空气分布器的反应釜和 1个结晶罐，氧化反应釜与结晶分离罐之间同时通过管道和固体泵连接。生产工艺流程为：在 170 °C下通入溶有 30 PPM结构式（Π ) 的金属卟啉， R₂= OH, R = H, M二 Mn，配位基为（¾( 00_ 以及 90 PPM Co (0A「）₂的对二甲苯，将 8 atm含氧 25%的富氧空气经气体分布器后通入搅拌反应釜 1的底部，反应器 2上部和下部的反应液分别经溢流和泵进入搅拌反应釜 2的底部，向搅拌反应器 2通入含氧 25%的富氧空气，搅拌反应器 2上部和下部的反应液分别经溢流和泵进入搅拌反应釜 3的底部，向搅拌反应器 3通入含氧 25%的富氧空气。控制对二甲苯流速使停留时间为 180分钟，控制空气流速使尾氧含量不超过 5%。反应器 3上部和下部的反应液分别经溢流和泵进入结晶分离罐。维持结晶分离罐温度和压力与氧化反应体系相同。对苯二甲酸从反应混合物中结晶出来并与对甲基苯甲酸、对甲基苯甲醇和对二甲苯分离。对甲基苯甲酸、对甲基苯甲醇和对二甲苯与含有金属卟啉催化剂的对二甲苯混合后通入搅拌反应釜 1进行二次氧化。上述过程连续循环。对二甲苯转化率为 96%，对苯二甲酸收率为 95%。 The reaction equipment consists of three reaction kettles with electric stirring and air distributor and a crystallizing tank, oxidizing The reaction vessel and the crystallization separation tank are simultaneously connected by a pipe and a solid pump. The production process is as follows: a metal porphyrin dissolved in 30 PPM structure (Π) is introduced at 170 °C, R ₂ = OH, R = H, M Mn, and the ligand is (3⁄4 ( 00_ and 90 PPM Co) (0A") ₂ of p-xylene, 8 atm oxygen-containing 25% oxygen-enriched air is passed through the gas distributor and then passed to the bottom of the stirred reactor 1, and the reaction liquids in the upper and lower portions of the reactor 2 are respectively overflowed and pumped. Entering the bottom of the stirred reactor 2, the oxygen-enriched air containing 25% of oxygen is introduced into the stirred reactor 2, and the reaction liquids in the upper and lower portions of the stirred reactor 2 are respectively overflowed and pumped into the bottom of the stirred reactor 3, stirring. The reactor 3 is supplied with oxygen-enriched air containing 25% oxygen. The p-xylene flow rate is controlled so that the residence time is 180 minutes, and the air flow rate is controlled so that the tail oxygen content does not exceed 5%. The reaction liquids in the upper and lower portions of the reactor 3 are respectively overflowed. The stream and pump enter the crystallization separation tank. The temperature and pressure of the crystallization tank are maintained the same as in the oxidation reaction system. Terephthalic acid is crystallized from the reaction mixture and separated from p-methylbenzoic acid, p-methylbenzyl alcohol and p-xylene. P-methylbenzoic acid, p-methylbenzyl alcohol and p-xylene Metalloporphyrin catalysts containing the mixed xylene into a stirred autoclave secondary oxidation. The above process continuous circulation. 96% conversion of p-xylene, 95% yield of terephthalic acid.

实施例 6: Example 6:

反应设备包括 2个带机械搅拌和空气分布器的反应釜和 1个结晶罐，氧化反应釜与结晶分离罐之间同时通过管道和固体泵连接。生产工艺流程为：在 185 °C下通入溶有 8 PPM结构式（ I ) 的金属卟啉， R产 N0₂， R₂= H, R Br， M= Cu 和 50 PPM异辛酸钴的对二甲苯，将 16 atm含 1% C0₂的空气经气体分布器后通入搅拌反应釜 1的底部，搅拌反应釜 1上部的反应液通过溢流通入搅拌反应釜 2, 搅拌反应釜 1下部的悬浮反应液通过泵泵入搅拌反应釜 2，在搅拌反应釜 2 中通入含 1% C02的空气。控制对二甲苯流速使停留时间为 130.分钟。控制空气流速使尾氧含量不超过 6%。反应器 2上部和下部的反应液分别经溢流和泵进入结晶分离罐。维持结晶分离罐 155°C和 l atm。对苯二甲酸从反应混合物中结晶出来并与对甲基苯甲酸、对甲基苯甲醇和对二甲苯分离。对甲基苯甲酸、对甲基苯甲醇和对二甲苯与含有金属卟啉催化剂的对二甲苯混合后通入搅拌反应釜The reaction apparatus comprises two reaction kettles with mechanical agitation and an air distributor and a crystallization tank, and the oxidation reaction kettle and the crystallization separation tank are simultaneously connected by a pipe and a solid pump. The production process is as follows: a metal porphyrin dissolved in 8 PPM of formula (I) is introduced at 185 °C, and R produces N0 ₂ , R ₂ = H, R Br, M = Cu and 50 PPM of cobalt octoate Toluene, 16 atm of air containing 1% C0 ₂ is passed through a gas distributor and then passed to the bottom of the stirred reaction vessel 1, and the reaction liquid in the upper portion of the stirred reactor 1 is passed through the overflow into the stirred reactor 2, and the suspension in the lower portion of the reactor 1 is stirred. The reaction liquid was pumped into the stirred reaction vessel 2 by a pump, and air containing 1% C02 was introduced into the stirred reaction vessel 2. The paraxylene flow rate was controlled so that the residence time was 130 minutes. The air flow rate is controlled so that the tail oxygen content does not exceed 6%. The reaction liquids at the upper and lower portions of the reactor 2 are respectively passed through an overflow and a pump into the crystallization separation tank. Maintain the crystallization separation tank at 155 ° C and l atm. Terephthalic acid crystallized from the reaction mixture Come out and separate from p-methylbenzoic acid, p-methylbenzyl alcohol and p-xylene. Mixing p-methylbenzoic acid, p-methylbenzyl alcohol and p-xylene with p-xylene containing metal porphyrin catalyst

1进行二次氧化。上述过程连续循环。对二甲苯转化率为 97%，对苯二甲酸收率为 95%。 1 Perform secondary oxidation. The above process is continuously cycled. The p-xylene conversion was 97% and the terephthalic acid yield was 95%.

实施例 7: Example 7

反应设备包括 1个带重力搅拌和空气分布器的反应釜和 1个结晶罐，氧化反应釜与结晶分离罐之间同时通过管道固体泵连接。生产工艺流程为：在 180 °C下通入溶有 2 PPM结构式结构式 ( II ) 的金属卟啉， R,= C3H7, R_;p H, R₂=N¾， M二 Cr，配位基 X为 Br的对二甲苯，将 10 atm含氧 19%的贫氧空气经气体分布器通入搅拌反应釜的底部，控制对二甲苯流速使停留时间为 110分钟，控制空气流速使尾氧含量不超过 5%。搅拌反应釜上部的反应液溢流通入结晶分离罐，搅拌反应釜下部的固体悬浮液经泵进入结分离罐。维持结晶分离罐 120°C和 1 atm。对苯二甲酸从反应混合物中结晶出来并与对甲基苯甲酸、对甲基苯甲醇和对二甲苯分离。对甲基苯甲酸、对甲基苯甲醇和对二甲苯与含有金属卟啉催化剂的对二甲苯混合后通入搅拌反应釜进行二次氧化。上述过程连续循环。对二甲苯转化率为 99%，对苯二甲酸收率为 95%。 The reaction apparatus comprises a reaction vessel with a gravity agitation and an air distributor and a crystallization tank, and the oxidation reactor and the crystallization separation tank are simultaneously connected by a pipeline solid pump. The production process is as follows: a metal porphyrin dissolved in 2 PPM of structural formula (II) is introduced at 180 °C, R, = C3H7, R _; p H, R ₂ = N3⁄4, M is Cr, and the ligand X is Br of p-xylene, 10 atm oxygen-containing 19% oxygen-lean air is passed through the gas distributor into the bottom of the stirred reactor, the paraxylene flow rate is controlled to make the residence time 110 minutes, and the air flow rate is controlled so that the tail oxygen content does not exceed 5%. The reaction liquid in the upper portion of the stirred reactor overflows into the crystallization separation tank, and the solid suspension in the lower portion of the stirred reactor is pumped into the knot separation tank. The crystal separation tank was maintained at 120 ° C and 1 atm. Terephthalic acid crystallizes from the reaction mixture and is separated from p-methylbenzoic acid, p-methylbenzyl alcohol and p-xylene. The p-methylbenzoic acid, p-methylbenzyl alcohol and p-xylene are mixed with p-xylene containing a metal porphyrin catalyst, and then passed through a stirred reaction vessel for secondary oxidation. The above process is continuously cycled. The p-xylene conversion was 99% and the terephthalic acid yield was 95%.

实施例 8: Example 8

反应设备包括 4个带电动搅拌和空气分布器的反应釜和 1个结晶罐，氧化反应釜与结晶分离罐之间同时通过管道和固体泵连接。生产工艺流程为：在 180 °C下通入溶有 5 PPM结构式（ I ) 的金属卟啉， R产 C₂ ， R₃= H， R₂二丽 e₂， M: Ni 和 300 PPM Cu₂Cl₂的对二甲苯，将 9 atm含 5% C0₂的空气经气体分布器通入反应釜 1的底部，反应器 2上部和下部的反应液分别经溢流和泵进入搅拌反应釜 2的底部，向搅拌反应器 2通入含 5% C0₂的空气，反应器 2的反应液依次进入反应器 3和 4和含 5% C0₂的空气混合。控制对二甲苯流速使停留时间为 140分钟，控制空气流速使尾氧含量不超过 5°/。。反应器 4上部和下部的反应液分别经溢流和泵进入结晶分离罐。维持结晶分离罐温度和压力与氧化反应体系相同。对苯； ί甲酸从反应混合物中结晶出来并与对甲基苯甲酸、对甲基苯甲醇和对二甲苯分离。对甲基苯甲酸、对甲基苯甲醇和对二甲苯与含有金属卟啉催化剂的对二甲苯混合后通入搅拌反应釜 1进行二次氧化。上述过程连续循环。对二甲苯转化率为 99%，对苯二甲酸收率为 98%。 The reaction apparatus comprises four reaction kettles with an electric stirring and an air distributor and a crystallizing tank, and the oxidation reactor and the crystal separation tank are simultaneously connected by a pipe and a solid pump. The production process is as follows: a metal porphyrin dissolved in 5 PPM of formula (I) is introduced at 180 °C, and R produces C ₂ , R ₃ = H, R ₂ liang e ₂ , M: Ni and 300 PPM Cu ₂ Cl ₂ of p-xylene, 9 atm of 5% C0 ₂ air is introduced into the bottom of the reaction vessel 1 through a gas distributor, and the reaction liquids in the upper and lower portions of the reactor 2 are respectively overflowed and pumped into the stirred reactor 2 At the bottom, the air containing 5% C0 ₂ is introduced into the stirred reactor 2, and the reaction liquid of the reactor 2 is sequentially introduced. Reactors 3 and 4 were mixed with 5% CO ₂ in air. The paraxylene flow rate was controlled so that the residence time was 140 minutes, and the air flow rate was controlled so that the tail oxygen content did not exceed 5 °/. . The reaction liquids in the upper and lower portions of the reactor 4 are respectively passed through an overflow and a pump into the crystallization separation tank. The temperature and pressure of the crystallization separation tank are maintained the same as in the oxidation reaction system. Benzene; methoxycarboxylic acid crystallized from the reaction mixture and separated from p-methylbenzoic acid, p-methylbenzyl alcohol and p-xylene. The p-methylbenzoic acid, p-methylbenzyl alcohol and p-xylene are mixed with p-xylene containing a metal porphyrin catalyst, and then passed through a stirred reaction vessel 1 for secondary oxidation. The above process is continuously cycled. The p-xylene conversion was 99%, and the terephthalic acid yield was 98%.

实施例 9: Example 9

反应设备包括 4个带电动搅拌和空气分布器的反应釜和 1个结晶罐，氧化反应釜与结晶分离罐之间同时通过管道和固体泵连接。生产工艺流程为：在 180 °C下通入溶有 5 PPM结构式 ( I ) 的金属卟啉， R = C H₅, R₃= H， R₂二丽 e₂， M= Zn 和 200 PPM Cu₂Cl₂的对二甲苯，将 11 atm含 5% C0₂的空气经气体分布器通入反应釜 1的底部，反应器 2上部和下部的反应液分别经溢流和泵进入搅拌反应釜 2的底部，向搅拌反应器 2通入含 5% (：0₂的空气，反应器 2的反应液依次进入反应器 3和 4和含 5% CO,的空气混合。控制对二甲苯流速使停留时间为 120分钟，控制空气流速使尾氧含量不超过 5%。反应器 4上部和下部的反应液分别经溢流和泵进入结晶分离罐。维持结晶分离罐温度为 155° ( ，压力与氧化反应体系相同。对苯二甲酸从反应混合物中结晶出来并与对甲基苯甲酸、对甲基苯甲醇和对二甲苯分离。对甲基苯甲酸、对甲基苯甲醇和对二甲苯与含有金属卟啉催化剂的对二甲苯混合后通入搅拌反应釜 1进行二次氧化。上述过程连续循环。对二甲苯转化率为 99%，对苯二甲酸收率 , 97%。 The reaction apparatus comprises four reaction kettles with an electric stirring and an air distributor and a crystallizing tank, and the oxidation reactor and the crystal separation tank are simultaneously connected by a pipe and a solid pump. The production process is as follows: a metal porphyrin dissolved in 5 PPM of formula (I) is introduced at 180 °C, R = CH ₅ , R ₃ = H, R ₂ liang e ₂ , M = Zn and 200 PPM Cu ₂ Cl ₂ of p-xylene, 11 atm of 5% C0 ₂ air is introduced into the bottom of the reactor 1 through a gas distributor, and the reaction liquids in the upper and lower portions of the reactor 2 are respectively overflowed and pumped into the stirred reactor 2 At the bottom, 5% (: 0 ₂ of air is introduced into the stirred reactor 2, and the reaction liquid of the reactor 2 is sequentially mixed into the reactors 3 and 4 and air containing 5% CO. The paraxylene flow rate is controlled to make the residence time. For 120 minutes, the air flow rate is controlled so that the tail oxygen content does not exceed 5%. The reaction liquids in the upper and lower portions of the reactor 4 are respectively passed through the overflow and pump into the crystallization separation tank. The temperature of the crystallization separation tank is maintained at 155 ° ( , pressure and oxidation reaction) The system is the same. Terephthalic acid crystallizes from the reaction mixture and is separated from p-methylbenzoic acid, p-methylbenzyl alcohol and p-xylene. p-Methylbenzoic acid, p-methylbenzyl alcohol and p-xylene with metal The p-xylene of the porphyrin catalyst is mixed and then introduced into the stirred reactor 1 for secondary oxygen. The above process was continuously cycled. The conversion of p-xylene was 99%, and the yield of terephthalic acid was 97%.

实施例 10: Example 10

反应设备包括 2个带电动搅拌和空气分布器的反应釜和 1个结晶罐，氧化反应釜与结晶分离罐之间同时通过管道和固体泵连接。生产工艺流程为：在 185 °C下通入溶有 8 PPM结构式（II ) 的金属卟啉，

H, M= Cr，配位基 X为 CI的对二甲苯，将 12 atm含氧 18%的贫氧空气经气体分布器后通入搅拌反应釜 1的底部，搅拌反应釜 1 h部的反应液通过溢流通入搅拌反应釜 2 , 搅拌反应釜 1下部的悬浮反应液通过泵泵入搅拌反应釜 2, 在搅拌反应釜 2 中通入含氧 18%的贫氧空气。控制对二甲苯流速使停留时间为 120分钟。控制空气流速使尾氧含量不超过 6%。反应器 ·2上部和下部的反应液分别经溢流和泵进入结晶分离罐。维持结晶分离罐温度为 155°C、压力为 l atm。对苯二甲酸从反应混合物中结晶出来并与对甲基苯甲酸、对甲基苯甲醇和对二甲苯分离。对甲基苯甲酸、对甲基苯甲醇和对二甲苯与含有金属卟啉催化剂的对二甲苯混合后通入搅拌反应釜 1进行二次氧化。上述过程连续循环。对二甲苯转化率为 99%，对苯二甲酸收率为 96%。 The reaction equipment consists of two reaction kettles with electric stirring and air distributor and a crystallizing tank, oxidizing The reaction vessel and the crystallization separation tank are simultaneously connected by a pipe and a solid pump. The production process is: introducing a metal porphyrin dissolved in 8 PPM of formula (II) at 185 °C.

H, M = Cr, the ligand X is CI paraxylene, 12 atm oxygen-containing 18% oxygen-depleted air is passed through the gas distributor and then passed to the bottom of the stirred reactor 1 to stir the reaction of the reactor 1 h The liquid was passed through the overflow into the stirred reactor 2, and the suspended reaction liquid in the lower portion of the stirred reactor 1 was pumped into the stirred reaction vessel 2, and 18% oxygen-depleted air was introduced into the stirred reactor 2. The paraxylene flow rate was controlled so that the residence time was 120 minutes. The air flow rate is controlled so that the tail oxygen content does not exceed 6%. The reaction liquids in the upper and lower portions of the reactor 2 were respectively passed through an overflow and a pump into a crystallization separation tank. The temperature of the crystallization separation tank was maintained at 155 ° C and the pressure was 1 atm. Terephthalic acid crystallizes from the reaction mixture and is separated from p-methylbenzoic acid, p-methylbenzyl alcohol and p-xylene. The p-methylbenzoic acid, p-methylbenzyl alcohol and p-xylene are mixed with p-xylene containing a metal porphyrin catalyst, and then passed through a stirred reaction vessel 1 for secondary oxidation. The above process is continuously cycled. The p-xylene conversion was 99% and the terephthalic acid yield was 96%.

Claims

权利要求 Rights request

1、一种空气氧化对二甲苯制备对苯二甲酸的方法，其特征在于，在由 1-4 个带有搅拌装置的反应釜串联组成的氧化反应器和结晶分离器串联的反应*** 中，向氧化反应器连续通入溶有卟啉催化剂的对二甲苯及 8 atm-20 atm的空气或者富氧或贫氧空气或者含二氧化碳的空气，上述卟啉催化剂为 1 PPM- 50 PPM 金属卟啉催化剂或者 1 PPM- 50 PPM金属卟啉与金属盐按浓度比 1 : 20-100混合的催化剂，在温度 140°C- 200°C条件下，对二甲苯在氧化反应器中停留 70分钟 180 分钟，氧化反应混合物经溢流或者泵 A与氧化反应***温度和压力相同的结晶器，或者泵入 1 atm和 120 °C-160 Ό的结晶器中进行常压恒温结晶，经分离得到的对二甲苯、对甲基苯甲酸和对甲基苯甲醇通入氧化反应器与含有金属卟啉催化剂的对二甲苯混合进入二次氧化，结晶经纯化得到精对苯二甲酸。 A method for preparing terephthalic acid by oxidizing p-xylene with air, characterized in that in a reaction system in which an oxidation reactor and a crystallizer are connected in series of 1-4 reactors with a stirring device, The oxidation reactor is continuously fed with p-xylene and 8 atm-20 atm dissolved in porphyrin catalyst or air rich in oxygen or oxygen-depleted air or carbon dioxide. The porphyrin catalyst is 1 PPM-50 PPM metal porphyrin. Catalyst or 1 PPM-50 PPM metal porphyrin and metal salt in a concentration ratio of 1: 20-100 mixed catalyst, at a temperature of 140 ° C - 200 ° C, p-xylene in the oxidation reactor for 70 minutes and 180 minutes The oxidation reaction mixture is subjected to overflow or pump A and the same temperature and pressure of the oxidation reaction system, or pumped into a crystallizer of 1 atm and 120 ° C - 160 Torr for constant temperature constant temperature crystallization, and the separated pair is obtained. Toluene, p-methylbenzoic acid and p-methylbenzyl alcohol are fed into an oxidation reactor and mixed with p-xylene containing a metal porphyrin catalyst to be subjected to secondary oxidation, and the crystals are purified to obtain purified terephthalic acid.

2、 .根据权利要求 1所述空气氧化对二甲苯制备对苯二甲酸的方 2. The method for preparing terephthalic acid by air oxidation of p-xylene according to claim 1.

( I ) (I)

( Π ) ( Π )

(III) (III)

法，其特征在于，金属卟啉催化剂具有通式（ I )或通式（11 )、通式（III) 的结构，通式（ I ) 的金属原子 M为过渡佘属原子 Co或 Cu、 Ni、 Zn、 Ru; 通式 ( II ).中的金属原子 M为 Fe或 Mn、 Cr; 通式（III) 中的金属原子， M₂为 Fe 或 Mn、 Cr; 通式（Π ) 中的配位基 X为乙酸或乙酰丙酮、卤素、酸根负离子；通式（ I ) 和（Π ) 和（III) 中取代基，，为氢或烃基、烷氧基、羟基、卤素、胺基、氨基、硝基。 The method is characterized in that the metal porphyrin catalyst has a structure of the general formula (I) or the general formula (11) and the general formula (III), and the metal atom M of the general formula (I) is a transition lanthanide atom Co or Cu, Ni , Zn, Ru; the metal atom M in the formula (II). is Fe or Mn, Cr; the metal atom in the formula (III), M ₂ is Fe or Mn, Cr; the formula in the formula (Π) The terminal group X is acetic acid or acetylacetone, a halogen, an acid anion; a substituent in the formula (I) and (Π) and (III), which is hydrogen or a hydrocarbon group, an alkoxy group, a hydroxyl group, a halogen group, an amine group, an amino group, Nitro.

3、根据权利要求 1所述空气氧化对二甲苯制备对苯二甲酸的方法，其特征在于，与金属卟啉构成复合催化剂的金属盐为过渡金属 Cu或 Zn、 Fe、 Co、 Mn、 Cr、 Ni的盐。 3. The method for preparing terephthalic acid by air oxidation of p-xylene according to claim 1, wherein the metal salt constituting the composite catalyst with the metal porphyrin is a transition metal Cu or Zn, Fe, Co, Mn, Cr, Ni salt.

4、 .根据权利要求 1所述空气氧化对二甲苯制备对苯二甲酸的方法，其特征在于，含二氧化碳的空气中二氧化碳的含量为 1%-5%。 4. A method of preparing terephthalic acid by air oxidation of p-xylene according to claim 1, characterized in that The carbon dioxide-containing air has a carbon dioxide content of 1% to 5%.

5、根据权利要求 1所述空气氧化对二甲苯制备对苯二甲酸的方法，其特征在于，氧化反应器连续通入溶有 5 PPM-10 PPM金属卟啉催化剂的对二甲苯及 lO atm- 12 atm的空气，在温度 170°C- 190°C条件下，对二甲苯在氧化反应器中停留 100分钟- 120 分钟，结晶分离器温度为 145°C- 160°C，压力为***压力或者结晶分离器温度为 130°C- 140°C，压力为 1 atm。 5. The method for preparing terephthalic acid by air oxidation of p-xylene according to claim 1, wherein the oxidation reactor is continuously introduced into p-xylene and lO atm-dissolved with 5 PPM-10 PPM metalloporphyrin catalyst. 12 atm air, at a temperature of 170 ° C - 190 ° C, p-xylene in the oxidation reactor for 100 minutes - 120 minutes, the crystallization separator temperature is 145 ° C - 160 ° C, the pressure is the system pressure or The crystallization separator temperature was 130 ° C - 140 ° C and the pressure was 1 atm.

6、根据权利要求 1所述空气氧化对二甲苯制备对苯二甲酸的方法，其特征在于，氧化反应器连续通入溶有 3 PPM-8 PPM金属卟啉与 60 PPM-200 PPM金属盐混合催化剂的对二甲苯及 10 atm-12 atm的空气，在温度 160°C 180°C条件下，对二甲苯在氧化反应器中停留 100分钟- 120 分钟，结晶分离器温度为 145 °C-160°C，压力为***压力或者结晶分离器温度为 130°C- 140°C，压力为 1 atm。 6. The method for preparing terephthalic acid by air oxidation of p-xylene according to claim 1, wherein the oxidation reactor is continuously mixed with a metal salt of 3 PPM-8 PPM and a metal salt of 60 PPM-200 PPM. Catalyst paraxylene and 10 atm-12 atm air, at a temperature of 160 ° C 180 ° C, p-xylene in the oxidation reactor for 100 minutes - 120 minutes, crystallization separator temperature of 145 ° C-160 °C, the pressure is the system pressure or the crystallization separator temperature is 130 ° C - 140 ° C, the pressure is 1 atm.

7、根据权利要求 1所述空气氧化对二甲苯制备对苯二甲酸的方法，其特征在于，所使用的设备包括串联的多级氧化反应器和结晶分离器构成的***，其中氧化反应器***为 1-4个串联的搅拌反应釜，结晶分离器为恒温高压结晶器或者恒温常压结晶器，氧化反应釜之间或者氧化反应釜与结晶分离罐之间除了通过管道串联以外，还连接有固体泵。 7. A method of producing terephthalic acid by air oxidation of p-xylene according to claim 1, wherein the apparatus used comprises a system comprising a multistage oxidation reactor and a crystallizer in series, wherein the oxidation reactor system 1-4 series stirred reactors, the crystallization separator is a constant temperature high pressure crystallizer or a constant temperature atmospheric pressure crystallizer, and between the oxidation reaction kettles or between the oxidation reaction reactor and the crystallization separation tank, in addition to being connected in series through a pipeline, Solid pump.

8、根据权利要求 7所述空气氧化对二甲苯制备对苯二甲酸的设备，其特征在于，所述的搅拌反应釜为机械搅拌反应釜或电动搅拌反应釜、磁力搅拌反应釜、超重力搅拌反应釜。 8. The apparatus for preparing terephthalic acid by air oxidation of p-xylene according to claim 7, wherein the stirred reaction kettle is a mechanically stirred reaction kettle or an electrically stirred reaction kettle, a magnetic stirring reaction kettle, and a super-gravity stirring. Reactor.