CN1241919C - Method for purifying compound of anhydrides aromatic carboxylic acid - Google Patents
Method for purifying compound of anhydrides aromatic carboxylic acid Download PDFInfo
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- CN1241919C CN1241919C CN 200410018803 CN200410018803A CN1241919C CN 1241919 C CN1241919 C CN 1241919C CN 200410018803 CN200410018803 CN 200410018803 CN 200410018803 A CN200410018803 A CN 200410018803A CN 1241919 C CN1241919 C CN 1241919C
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- acid anhydride
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Abstract
The present invention relates to a purification method and a technique for aromatic carboxylic acid anhydride class compounds, a complexing solvent is used for the complexing recrystallization of aromatic carboxylic acid anhydrides, and a mixed solvent is used for the crystal form reformation of complexing recrystallization products. The present invention has a main technique that the complexing solvent and carboxylic acid anhydrides of a low grade fatty group are added in a kettle and are heated and stirred, crude product fragrant carboxylic acid anhydrides are added and are heated until completely dissolved, and then adsorption decolorant is added so as to obtain fragrant carboxylic acid anhydride complex compounds. A solvent for reforming the crystal form and the complex compounds are added in the crystal form reformation kettle and are stirred at normal temperature or in heating until a crystalline and dry state. The present invention solves the problems of complicate techniques, poisonous processes, dry solvent, waste water, exhaust gas and dust generation in the processes, low product rate and poor service performance.
Description
Technical field
The present invention relates to the manufacturing of aromatic carboxylic acid compound anhydride, particularly relate to the method for purification and the technology of aromatic carboxylic acid compound anhydride.
Background technology
The industrial activity aromatic tricarboxylic acid anhydride that utilizes various reactions directly to make as products such as pyromellitic acid anhydride, phthalic anhydride, replacement phthalic anhydride, naphthalene acid anhydride, replacement naphthalene acid anhydrides, contains plurality of impurities usually at present, needs could satisfy higher application requiring through purifying.Because aromatic carboxylic acid compound anhydride chemical property is active, easy and multiple material generation chemical reaction, therefore, treating process regular meeting causes quality product to reduce or the impure problem of product with all kinds of side reactions (hydrolysis, acidylate, decarboxylation).This shows that in higher degree aromatic tricarboxylic acid anhydride production process, product separation is comparatively complicated, difficult and very crucial problem with making with extra care.
With the pyromellitic acid anhydride is example, at present industrial many employing durols or other alkylbenzenes are raw material, at first make the crude product pyromellitic acid anhydride through catalyzed oxidation, then the crude product pyromellitic acid anhydride is hydrolyzed into Pyromellitic Acid, and then Pyromellitic Acid carried out recrystallizing and refining, obtain the elaboration Pyromellitic Acid, the elaboration Pyromellitic Acid makes block pyromellitic acid anhydride product through vacuum hydro-extraction, distillation, can get powder-like product through pulverizing.There is the numerous length of operational path in this technology, and product yield is low, has a large amount of processing wastewaters to produce, the sublimation process contaminate environment, and the finished product crushing process produces dust, and the crystal formation of product and use properties are not good, and the user uses inconvenient problem.
In order to solve the refining problem of pyromellitic acid anhydride, Japan's publication clear 454050 has proposed the recrystallizing and refining method of Yong diox-aceticanhydride mixture as solvent, though this method operation is simpler, product yield and better quality, but since the diox solvent toxicity big, cost an arm and a leg and exist a large amount of acetic acid to handle problems, be not suitable for industrial applications; Japan's publication clear 5058024 has proposed the method with the mixed solvent washing, and this method can not be removed the insoluble impurities in the product, and has the solvent seasoning problem.U.S. Pat P4370487 utilizes pyromellitic acid anhydride optionally to form the character of complex compound with aromatic hydrocarbon, ether, the clathrate separation method has been proposed, this method can make the pyromellitic acid anhydride product of higher degree, but has difficult problems such as product crystallization not good (mostly being powdery) and solvent seasoning.
Summary of the invention
The objective of the invention is to provide a kind of method of purification and technology of aromatic carboxylic acid compound anhydride at the above-mentioned defective that exists in the prior art.
Technical scheme of the present invention is to utilize aromatic tricarboxylic acid anhydride optionally to form complex compound with aromatic hydrocarbon, aromatic oxide, benzylic ether, removes the moisture content that exists in system and the material, contains reactive hydrogen impurity and the hydrolysis of inhibition aromatic tricarboxylic acid anhydride with 0.01～25% acetic anhydride, propionic anhydride, Succinic anhydried or its mixture of complexing recrystallization solvent consumption; Aromatic tricarboxylic acid anhydride and complex compound thereof are through heating in mixed solvent or boil the character that changes product crystal formation and granularity, it with aromatic tricarboxylic acid anhydride/solvent 1: 1～20 complexing recrystallization solvent aryl ethers, methyl-phenoxide in benzylic ether and the alkyl benzene, phenyl ethyl ether, propyl phenyl ether, the phenyl tertbutyl ether, benzyl methyl ether, benzyl ethyl ether, the benzyl propyl ether, the benzyl tertbutyl ether, phenyl ether, dimethylbenzene, diethylbenzene, two propyl benzene, a kind of in a kind of or its mixture in the trimethylbenzene carries out the complexing recrystallization to aromatic tricarboxylic acid anhydride, with 0.5～10 times acetic anhydride of aromatic tricarboxylic acid anhydride or its complex compound, acetate, acetone, butanone, ethyl acetate, ether, benzene, toluene, a kind of solvent or a kind of solvent in its mixture in the tetrahydrofuran (THF) carry out the crystal formation transformation to its complexing recrystallized product; Its technological process is: in complexing recrystallizing and refining still, add above-mentioned complexing recrystallization solvent and acetic anhydride, propionic anhydride, Succinic anhydried or its mixture aliphatic carboxylic acid acid anhydride, the heating and stirred 0～10 hour, add the crude product aromatic tricarboxylic acid anhydride, reinforced finishing, under agitation heat temperature raising to aromatic tricarboxylic acid anhydride all dissolves, 0～50% the adsorption decolouriser that adds crude product aromatic tricarboxylic acid anhydride weight, maintenance effect 0～10 hour, filtered while hot, filtrate concentrate or do not concentrate, cooling, filter, obtain the aromatic tricarboxylic acid anhydride complex compound; Transform in the still at crystal formation, add a kind of solvent or a kind of solvent in its mixture and above-mentioned aromatic tricarboxylic acid anhydride complex compound in acetic anhydride, acetate, acetone, butanone, ethyl acetate, ether, benzene, toluene, the tetrahydrofuran (THF), stirring action under normal temperature or heated condition, crystalline state and granularity until aromatic tricarboxylic acid anhydride reach the product index requirement, through cooling, filter, drying makes elaboration aromatic tricarboxylic acid anhydride granular crystal.
This processing method is applicable to the pyromellitic acid anhydride in aromatic tricarboxylic acid anhydride and the many acid anhydrides, 1,2,3, the 4-pyromellitic dianhydride, 1-carboxyl phthalic anhydride, 2-carboxyl phthalic anhydride, the 1-chloride anhydride, the 2-chloride anhydride, 1,4-dichloro phthalic anhydride, 2,3-dichloro phthalic anhydride, 1,2,3, the 4-tetrachlorophthalic anhydride, 1-fluorobenzene acid anhydride, 2-fluorobenzene acid anhydride, 1,4-difluoro phthalic anhydride, 2,3-difluoro phthalic anhydride, 1,2,3,4-tetrafluoro phthalic anhydride, 1-cyano group phthalic anhydride, 2-cyano group phthalic anhydride, 1-nitro phthalic anhydride, 2-nitro phthalic anhydride, 1,2-naphthalene acid anhydride, 2,3-naphthalene acid anhydride, 2,3,6,7-naphthalenetetracarbacidic acidic dianhydride, 1,2,5,6-naphthalenetetracarbacidic acidic dianhydride, 2,3,9, the luxuriant and rich with fragrance tetracarboxylic acid dianhydride of 10-, 2,3,4, making with extra care of 5-thiophene dianhydride, purify and the product modification, be particularly useful for pyromellitic acid anhydride, 1,2,3, the 4-pyromellitic dianhydride, 2,3,6,7-naphthalenetetracarbacidic acidic dianhydride, 1,2,5,6-naphthalenetetracarbacidic acidic dianhydride, 2,3,9, the luxuriant and rich with fragrance tetracarboxylic acid dianhydride of 10-refining, purify and the product modification.
The used complexing recrystallization solvent of this processing method is aryl ethers, benzylic ether and alkyl benzene, comprise: a kind of in a kind of or its mixture in methyl-phenoxide, phenyl ethyl ether, propyl phenyl ether, phenyl tertbutyl ether, benzyl methyl ether, benzyl ethyl ether, benzyl propyl ether, benzyl tertbutyl ether, phenyl ether, dimethylbenzene, diethylbenzene, two propyl benzene, the trimethylbenzene, especially better with methyl-phenoxide, phenyl ethyl ether, dimethylbenzene; Complexing recrystallization solvent consumption preferred range is that aromatic tricarboxylic acid anhydride/solvent is 1: 1～20, and optimum range is 1: 3～10.
Complexing recrystallization process in this processing method adds above-mentioned aliphatic carboxylic acid acid anhydride and removes moisture in material and the system, contains reactive hydrogen impurity and suppress the hydrolytic side reactions of aromatic tricarboxylic acid anhydride.Above-mentioned aliphatic carboxylic acid acid anhydride is a kind of, especially better with acetic anhydride in a kind of or its mixture in acetic anhydride, propionic anhydride, the Succinic anhydried; The consumption of aliphatic carboxylic acid acid anhydride is 0.01～25% of a complexing recrystallization solvent consumption, with 0.1～5% the best.
The used sorbent material of complexing recrystallization process is a kind of, especially better with gac in a kind of or its mixture in gac, neutrality or acidic alumina, kaolin, the molecular sieve; The sorbent material consumption is 0.5～20% of an aromatic tricarboxylic acid anhydride consumption, with 2～10% the bests.
The complexing extraction temperature is the reflux temperature of normal temperature to system, adopts its higher temperature to help the purification with product of removing of impurity, helps improving product yield and equipment capacity.
In order to improve the complex compound yield, the mother liquor behind the refining heat filtering of complexing can require to carry out concentration according to raw materials quality and quality product.Concentration process can carry out under normal pressure or vacuum, and the solvent amount of steaming is to guarantee that system has good flowability and is as the criterion.
The crystal formation transformation solvent of aromatic tricarboxylic acid anhydride or its complex compound is a kind of solvent in acetic anhydride, acetate, acetone, butanone, ethyl acetate, ether, benzene, toluene, the tetrahydrofuran (THF) or a kind of solvent in its mixture, with a kind of preferred solvents in acetic anhydride, acetate, acetone, ether or its mixture; Crystal formation transformation solvent load is aromatic tricarboxylic acid anhydride or its complex compound 0.5～10 times, with 2～5 times of the bests.
Crystal formation transform temperature be normal temperature to the solvent refluxing temperature, its higher temperature helps finishing fast of crystal formation transformation.
In the treatment time that crystal formation is transformed, control flexibly according to product quality indicator requirement and definite operational condition, with 0.01～10 hour the best.
Beneficial effect of the present invention: the numerous long diox equal solvent toxicity of operational path that has solved the preceding method existence simultaneously is big, aromatic tricarboxylic acid anhydride generation side reaction, the solid insoluble impurities can't be removed, the solvent seasoning dehydration, produce processing wastewater, distillation waste gas and finished powder flour dust pollution in the production process, product yield is low, crystal formation and granularity is not good, use properties is poor, use problems such as inconvenience.
Example 1
In the 500mL four-hole bottle, add methyl-phenoxide 300mL, acetic anhydride 4mL, be warming up to 120 ℃ under stirring, slowly add 50g crude product pyromellitic acid anhydride, be warming up to 150 ℃ under stirring and make its dissolving fully, add the 5g gac, act on 1 hour down in reflux temperature, filtered while hot is collected mother liquor, cools to below 10 ℃ under stirring at a slow speed, filter, obtain glassy yellow crystalline solid filter cake.The mixed solvent that adds 110mL acetic anhydride/acetate=1: 1 in the above-mentioned filter cake, be warming up to backflow under slow the stirring, stirring action is 1.5 hours under reflux temperature, after crystal habit reaches requirement, is cooled to 20 ℃, filter, get the granular crystal solid, vacuum-drying gets white elaboration pyromellitic acid anhydride crystalline solid 37g, product yield 74%, purity 99.85%.
Example 2
In the 500mL four-hole bottle, add dimethylbenzene 300mL, acetic anhydride 2mL, be warming up to 120 ℃ under stirring, slowly add 15g crude product pyromellitic acid anhydride, be warming up to backflow under stirring it is dissolved fully, add the 2g gac, act on 1 hour down in reflux temperature, filtered while hot is collected mother liquor, cools to below 10 ℃ under stirring at a slow speed, filter, obtain little yellow crystal solid filter cake.In the above-mentioned filter cake, add the mixed solvent of 30mL acetic anhydride/acetate=1: 1, be warming up to backflow under slow the stirring, in reflux temperature effect 1 hour, after crystal habit reaches requirement, be cooled to 20 ℃, filter, get the granular crystal solid, vacuum-drying, get little yellow elaboration pyromellitic acid anhydride crystalline solid 10.8g, productive rate 72%, product purity 99.05%.
Example 3
In the 300L refining kettle, add methyl-phenoxide 200L, acetic anhydride 3L stirs down heat temperature raising to 120 ℃, the slow 30kg crude product pyromellitic acid anhydride that adds, finish, be warming up to and make its dissolving more than 150 ℃ fully, add the 1.5kg gac, the maintenance effect is 1 hour under reflux temperature, filtered while hot with 10L methyl-phenoxide washing filter residue, is collected filtrate, filtrate is stirred heating down, steam acetic anhydride and methyl-phenoxide 180L, leftover materials were with 1.5 hours, cool at a slow speed below 20 ℃, maintenance effect 30 minutes is filtered, and gets glassy yellow crystalline solid filter cake.In the above-mentioned filter cake, add the mixed solvent of 75L acetate/acetic anhydride=4: 1, stir and be warming up to backflow, maintenance effect 1.5 hours down slowly, after crystal habit meets the requirements, be cooled to slowly below 20 ℃, maintenance effect 1 hour is filtered, vacuum-drying, get elaboration pyromellitic acid anhydride white particulate crystalline solid 26.5kg, product yield 88.3%, product purity 99.75%.Parent solution solvents can partly directly be applied mechanically or be distilled and reclaim the back reuse.
Claims (8)
1, the method of purification of aromatic carboxylic acid compound anhydride and technology, it is characterized in that: utilize aromatic tricarboxylic acid anhydride optionally and aromatic hydrocarbon, aromatic oxide, benzylic ether forms complex compound, 0.01～25% acetic anhydride with complexing recrystallization solvent consumption, propionic anhydride, Succinic anhydried or its mixture remove the moisture content that exists in system and the material, contain reactive hydrogen impurity and suppress the aromatic tricarboxylic acid anhydride hydrolysis, aromatic tricarboxylic acid anhydride and complex compound thereof are through heating in mixed solvent or boil the character that changes product crystal formation and granularity, it with aromatic tricarboxylic acid anhydride/solvent 1: 1～20 complexing recrystallization solvent aryl ethers, methyl-phenoxide in benzylic ether and the alkyl benzene, phenyl ethyl ether, propyl phenyl ether, the phenyl tertbutyl ether, benzyl methyl ether, benzyl ethyl ether, the benzyl propyl ether, the benzyl tertbutyl ether, phenyl ether, dimethylbenzene, diethylbenzene, two propyl benzene, a kind of in a kind of or its mixture in the trimethylbenzene carries out the complexing recrystallization to aromatic tricarboxylic acid anhydride, with 0.5～10 times acetic anhydride of aromatic tricarboxylic acid anhydride or its complex compound, acetate, acetone, butanone, ethyl acetate, ether, benzene, toluene, a kind of solvent or a kind of solvent in its mixture in the tetrahydrofuran (THF) carry out the crystal formation transformation to its complexing recrystallized product; Its technological process is: in complexing recrystallizing and refining still, add above-mentioned complexing recrystallization solvent and acetic anhydride, propionic anhydride, Succinic anhydried or its mixture aliphatic carboxylic acid acid anhydride, the heating and stirred 0～10 hour, add the crude product aromatic tricarboxylic acid anhydride, reinforced finishing, under agitation heat temperature raising to aromatic tricarboxylic acid anhydride all dissolves, 0～50% the adsorption decolouriser that adds crude product aromatic tricarboxylic acid anhydride weight, maintenance effect 0～10 hour, filtered while hot, filtrate concentrate or do not concentrate, cooling, filter, obtain the aromatic tricarboxylic acid anhydride complex compound; Transform in the still at crystal formation, add a kind of solvent or a kind of solvent in its mixture and above-mentioned aromatic tricarboxylic acid anhydride complex compound in acetic anhydride, acetate, acetone, butanone, ethyl acetate, ether, benzene, toluene, the tetrahydrofuran (THF), stirring action under normal temperature or heated condition, crystalline state and granularity until aromatic tricarboxylic acid anhydride reach the product index requirement, through cooling, filter, drying makes elaboration aromatic tricarboxylic acid anhydride granular crystal.
2, the method of purification of aromatic carboxylic acid compound anhydride according to claim 1 and technology is characterized in that being applicable to the pyromellitic acid anhydride in aromatic tricarboxylic acid anhydride and the many acid anhydrides, 1,2,3, the 4-pyromellitic dianhydride, 1-carboxyl phthalic anhydride, 2-carboxyl phthalic anhydride, the 1-chloride anhydride, the 2-chloride anhydride, 1,4-dichloro phthalic anhydride, 2, the 3-chloride anhydride, 1,2,3, the 4-tetrachlorophthalic anhydride, 1-fluorobenzene acid anhydride, 2-fluorobenzene acid anhydride, 1,4-difluoro phthalic anhydride, 2,3-difluoro phthalic anhydride, 1,2,3,4-tetrafluoro phthalic anhydride, 1-cyano group phthalic anhydride, 2-cyano group phthalic anhydride, 1-nitro phthalic anhydride, 2-nitro phthalic anhydride, 1,2-naphthalene acid anhydride, 2,3-naphthalene acid anhydride, 2,3,6,7-naphthalenetetracarbacidic acidic dianhydride, 1,2,5,6-naphthalenetetracarbacidic acidic dianhydride, 2,3,9, the luxuriant and rich with fragrance tetracarboxylic acid dianhydride of 10-, 2,3,4,5-thiophene dianhydride refining, purify and the product modification.
3, the method for purification of aromatic carboxylic acid compound anhydride according to claim 1 and technology, it is characterized in that used adsorption decolouriser is gac, neutrality or acidic alumina, a kind of in a kind of or its mixture in kaolin, the molecular sieve, the sorbent material consumption is 0.5～20% of an aromatic tricarboxylic acid anhydride consumption.
4, the method for purification of aromatic carboxylic acid compound anhydride according to claim 1 and technology is characterized in that the complexing extraction temperature is the reflux temperature of normal temperature to system.
5, the method for purification of aromatic carboxylic acid compound anhydride according to claim 1 and technology is characterized in that the filtrate concentration process carries out under normal pressure or vacuum.
6, it is a kind of in a kind of or its mixture in acetic anhydride, acetate, acetone, butanone, ethyl acetate, ether, benzene, toluene, the tetrahydrofuran (THF) that the method for purification of aromatic carboxylic acid compound anhydride according to claim 1 and technology, the crystal formation that it is characterized in that aromatic tricarboxylic acid anhydride or its complex compound are transformed solvent.
7, the method for purification and the technology of the described aromatic carboxylic acid compound anhydride of claim 1 is characterized in that it is that normal temperature is to the solvent refluxing temperature that crystal formation is transformed temperature.
8, the method of purification of aromatic carboxylic acid compound anhydride according to claim 1 and technology is characterized in that: in the 300L refining kettle, add methyl-phenoxide 200L, acetic anhydride 3L, stir down heat temperature raising to 120 ℃, add 30kg crude product pyromellitic acid anhydride slowly, finish, be warming up to and make its dissolving more than 150 ℃ fully, add the 1.5kg gac, the maintenance effect is 1 hour under reflux temperature, filtered while hot, with 10L methyl-phenoxide washing filter residue, collect filtrate, filtrate is stirred heating down, steams acetic anhydride and methyl-phenoxide 180L, leftover materials, with 1.5 hours, cool to below 20 ℃ maintenance effect 30 minutes at a slow speed, filter, get glassy yellow crystalline solid filter cake.In the above-mentioned filter cake, add the mixed solvent of 75L acetate/acetic anhydride=4: 1, stir and be warming up to backflow, maintenance effect 1.5 hours down slowly, after crystal habit meets the requirements, be cooled to slowly below 20 ℃, maintenance effect 1 hour is filtered, vacuum-drying, get elaboration pyromellitic acid anhydride white particulate crystalline solid 26.5kg, product yield 88.3%, product purity 99.75%.
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| CN 200410018803 CN1241919C (en) | 2004-03-29 | 2004-03-29 | Method for purifying compound of anhydrides aromatic carboxylic acid |
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| CN 200410018803 CN1241919C (en) | 2004-03-29 | 2004-03-29 | Method for purifying compound of anhydrides aromatic carboxylic acid |
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| CN1241919C true CN1241919C (en) | 2006-02-15 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102079734A (en) * | 2009-11-26 | 2011-06-01 | 浙江启明药业有限公司 | Circulating economic comprehensive treatment method for industrial production of tetrachlorophthalic anhydride |
| CN104892621B (en) * | 2015-05-25 | 2017-04-26 | 常熟联邦化工股份有限公司 | Energy-saving emission-reduction process for producing pyromellitic dianhydride in solvent refining method |
| CN113527240B (en) * | 2021-07-19 | 2022-11-29 | 绍兴华为化工有限公司 | Refining process of tetrachlorophthalic anhydride |
| CN113583016A (en) * | 2021-09-01 | 2021-11-02 | 潍坊弘润新材料有限公司 | Method for improving purity of crude pyromellitic dianhydride, device and application thereof |
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