CN1583703A - Crystal pelleting and purifying method of aromatic carboxylic acid products - Google Patents
Crystal pelleting and purifying method of aromatic carboxylic acid products Download PDFInfo
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- CN1583703A CN1583703A CN 200410019481 CN200410019481A CN1583703A CN 1583703 A CN1583703 A CN 1583703A CN 200410019481 CN200410019481 CN 200410019481 CN 200410019481 A CN200410019481 A CN 200410019481A CN 1583703 A CN1583703 A CN 1583703A
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- acid anhydride
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Abstract
The present invention relates to crystallization granulating and purifing method for aromatic carboxylic anhydride products. Said method is as following: Adding a low alphatic carboxylic acid anhydride or mixture solvents thereof, heating, adding on part aromatic anhydride and 0-50% part absorption bleaching agents with stir to absorb 0-10 hours, or boiling said aromatic anhydride under reflux temperature for 0-10 hours, then filtering under heat, concentrating the filtrate or not, coolin, filtering, drying to give final aromatic carboxylic anhydride granule crystallines. By using the method of the present invention to crystallization granulating and purifying aromatic carboxylic anhydride products, can solve the crystallizationg ranulating and dust pollution problems, and meanwhile increase the purity and property of the products.
Description
Technical field
The present invention relates to the manufacturing of aromatic tricarboxylic acid anhydride series products, particularly relate to crystallization granulation and the purification process and the technology of aromatic tricarboxylic acid anhydride series products.
Background technology
The present 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, usually mostly be powder-like product and contain plurality of impurities, need to satisfy higher application requiring through purification and crystallization granulation.Because aromatic carboxylic acid compound anhydride chemical property is active, easy and multiple material generation chemical reaction, in refining and crystallization granulation process, regular meeting reduces quality product with all kinds of side reactions.Therefore, crystallization granulation and purifying are the key issues of the high-quality aromatic tricarboxylic acid anhydride series products of preparation.
With the pyromellitic acid anhydride is example, and at present industrial many employing durols are raw material, make through a series of processes such as catalyzed oxidation, the hydrolysis of crude product pyromellitic acid anhydride, Pyromellitic Acid recrystallizing and refining, vacuum hydro-extraction, distillation, pulverizing.The numerous length of this operational path has processing wastewater to produce, sublimation process loss of material and seriously polluted, and product yield is low, and products obtained therefrom is powdery, and processing and use have serious dust pollution, and use properties is not good, and it is inconvenient to use.
In order to solve the refining problem of pyromellitic acid anhydride, Japan's publication clear 454050 has proposed with the recrystallizing and refining method of dioxane-aceticanhydride mixture as solvent, Japan's publication clear 5058024 has proposed the method with the mixed solvent washing, U.S. Pat P4370487 has proposed the clathrate separation method, up to now, still have nothing to do in the report of product crystallization granulation.
Summary of the invention
The purpose of this invention is to provide a kind of crystallization granulation and purification process of aromatic tricarboxylic acid anhydride series products, improved quality product and application performance, thereby effectively solved the problem that exists in the background technology.
Technical scheme of the present invention is: add the lower aliphatic carboxylic acid anhydride or contain the mixed solvent of lower aliphatic carboxylic acid anhydride in reactor, heating, under agitation add a kind of in many acid anhydrides of many acid anhydrides, heterocycle acid anhydrides or heterocycle acid anhydrides of many acid anhydrides, cycloaliphatic ring acid anhydrides or cycloaliphatic ring acid anhydrides of crude product aromatic tricarboxylic acid anhydride or aromatic tricarboxylic acid anhydride and be equivalent to the adsorption decolouriser of above-mentioned material umber 0～50%, adsorption 0～10 hour, heat filtering, filtrate concentrates or does not concentrate, cooling, filtration, drying, makes elaboration aromatic tricarboxylic acid anhydride granular crystal.
Technical scheme of the present invention can also be: add the lower aliphatic carboxylic acid anhydride or contain the mixed solvent of lower aliphatic carboxylic acid anhydride in reactor, stir a kind of in many acid anhydrides of many acid anhydrides, heterocycle acid anhydrides or heterocycle acid anhydrides of the many acid anhydrides, cycloaliphatic ring acid anhydrides or the cycloaliphatic ring acid anhydrides that add crude product aromatic tricarboxylic acid anhydride or aromatic tricarboxylic acid anhydride down, heating, make its part or all of dissolving, the heat effect of boiling 0～10 hour, material concentrates or does not concentrate, cooling, filtration, drying, makes elaboration aromatic tricarboxylic acid anhydride granular crystal.
The principle of technique scheme is: with the lower aliphatic carboxylic acid anhydride or contain the mixed solvent of lower aliphatic carboxylic acid anhydride; aromatic tricarboxylic acid anhydride class material is carried out recrystallization or heat is boiled processing; the lower aliphatic carboxylic acid anhydride can remove the activity impurity in the system; prevent side reactions such as aromatic tricarboxylic acid anhydride generation hydrolysis; utilize material that the character of crystalline particle or crystal formation conversion can take place in solvent, the aromatic carboxylic acid compound anhydride is carried out crystallization granulation and purifying products.
Many acid anhydrides of described aromatic tricarboxylic acid anhydride of the inventive method or aromatic tricarboxylic acid anhydride, many acid anhydrides of cycloaliphatic ring acid anhydrides or cycloaliphatic ring acid anhydrides, many acid anhydrides of heterocycle acid anhydrides or heterocycle acid anhydrides can be in the following material a kind of: pyromellitic acid anhydride, 1,2,3, the 4-pyromellitic dianhydride, 1 (or 2)-carboxyl phthalic anhydride, 1 (or 2)-mono chloro benzene acid anhydride, 1,4-dichloro phthalic anhydride, 2,3-dichloro phthalic anhydride, 1,2,3, the 4-tetrachlorophthalic anhydride, 1 (or 2)-fluorobenzene acid anhydride, 1,4-difluoro phthalic anhydride, 2,3-difluoro phthalic anhydride, 1,2,3,4-tetrafluoro phthalic anhydride, 1 (or 2)-cyano group phthalic anhydride, 1 (or 2)-nitro phthalic anhydride, 3,4,3 ', 4 '-bibenzene tetracarboxylic dianhydride, 2,3,2 ', 3 '-bibenzene tetracarboxylic dianhydride, 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-, 3,4,9, the 10-tetracarboxylic acid dianhydride, 1,2,3,4-encircles glutaric anhydride, 2,3,4,5-tetramethyleneimine dianhydride, 2,3,4, a kind of in the 5-thiophene dianhydride, particularly pyromellitic acid anhydride, 1,2,3, the 4-pyromellitic dianhydride, 3,4,3 ', 4 '-bibenzene tetracarboxylic dianhydride, 2,3,2 ', 3 '-bibenzene tetracarboxylic 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-, 3,4,9, the 10-tetracarboxylic acid dianhydride.
Described recrystallization or heat are boiled solvent can or contain the mixed solvent of lower aliphatic carboxylic acid anhydride for the lower aliphatic carboxylic acid anhydride; Lower aliphatic carboxylic acid anhydride in the described solvent can be a kind of in a kind of or its mixture in acetic anhydride, propionic anhydride, the Succinic anhydried; Other compositions in the described solvent can be a kind of in a kind of or its mixture in acetate, acetone, butanone, ethyl acetate, ether, benzene, toluene, the tetrahydrofuran (THF); The preferred range that recrystallization or heat are boiled the solvent for use consumption can be aromatic tricarboxylic acid anhydride: solvent is 1 part: 1～20 part, be preferably 1 part: 2～10 parts.
Boil in the used solvent at described recrystallization or heat, its composition can be the lower aliphatic carboxylic acid anhydride: other compositions are 0～100 part: the arbitrary proportion in 1 part.
Used sorbent material can be a kind of in a kind of or its mixture in gac, neutrality or acidic alumina, kaolin, the molecular sieve in the described recrystallization process, is preferably gac.The consumption of described sorbent material can be preferably 1～10% for 0～20% of aromatic tricarboxylic acid anhydride consumption.
Described recrystallization or heat are boiled the reflux temperature that the temperature of processing can be from normal temperature to system, are preferably reflux temperature or a little less than reflux temperature.
In order to improve product yield, to adjust grain size number, recrystallization heat filtering or heat are boiled the material that obtains after the processing, can carry out concentration under normal pressure or vacuum.
The treatment time of described recrystallization is to be 0～20 hour, and the adsorption bleaching time is preferably 0.1～3 hour.
The treatment time that described heat is boiled can be 0～20 hour, is preferably 0.1～5 hour.
Method of the present invention has effectively solved the numerous length of the operational path that exists in the background technology, the dioxane solvent toxicity is big, the processing wastewater that produces in the production process, distillation waste gas and dust pollution, the problems such as crystallization granulation that the product use properties is not good, use inconvenience and product.
Embodiment
Below in conjunction with specific embodiment the inventive method is specified.The inventive method should include but not limited to the disclosed technology contents of following examples.
Embodiment 1
In the 500mL four-hole bottle, add 100 parts of 100 parts of acetic acid and acetic anhydride, be mixed with acetic acid/acetic anhydride mixed solvent, stirred down in 10～30 minutes, be warming up to 60 ℃, add 50 parts of purity and be 98.35% crude product pyromellitic acid anhydride, stirred down, be warming up to 122～124 ℃ reflux temperature in 20～30 minutes, and under this temperature, reacted 1 hour, cooled to below 20 ℃ with water-bath with 1 hour approximately under stirring, filter, obtain the granular crystal solid, vacuum-drying, get 45 parts of white or faint yellow pyromellitic acid anhydride crystalline products, product yield 90%, purity 99.24%.
Embodiment 2
In the 500mL four-hole bottle, add 210 parts of 90 parts of acetic acid and acetic anhydride, be mixed with acetic acid/acetic anhydride mixed solvent, stir down and be warming up to 80 ℃ with 20～30 minutes, add 50 parts of purity and be 98.26% crude product pyromellitic acid anhydride and 3g gac, heating up under stirring makes its dissolving fully, and acts on 0.5 hour down, filtered while hot in reflux temperature, collect mother liquor, cooled to below 20 ℃ with water-bath with 30 minutes approximately under stirring, filter, obtain the granular crystal solid, vacuum-drying, get 41 parts of white or faint yellow pyromellitic acid anhydride crystalline products, product yield 82%, purity 99.34%.
Embodiment 3
In the 500mL four-hole bottle, add 125 parts of 125 parts in acetone and acetic anhydride, be mixed with acetone/acetic anhydride mixed solvent, stir down with being warming up to reflux temperature in 20～30 minutes, adding 50 parts of purity is 98.26% crude product pyromellitic acid anhydride and 5 parts of gacs, heating up under stirring makes its dissolving fully, and acts on 0.5 hour down, filtered while hot in reflux temperature, collect mother liquor, cool to below 15 ℃ with ice-water bath again with water-bath earlier under stirring, filter, obtain the granular crystal solid, vacuum-drying, get 39 parts of white pyromellitic acid anhydride crystalline products, product yield 78%, purity 99.53%.
Embodiment 4
In the 500mL four-hole bottle, add 200 parts of 100 parts of acetic acid and acetic anhydride, be mixed with acetic acid/acetic anhydride mixed solvent, be warming up to 80 ℃ under stirring, add 50 parts of purity and be crude product pyromellitic acid anhydride and 3 parts of gacs of 98.36%, stirring heats up down makes its dissolving fully, and in reflux temperature effect 0.5 hour down, filtered while hot, collect mother liquor, 200 parts of heating distilling off solvent, water-bath cooled to below 20 ℃ under the residue mother liquor stirred, filter, obtain the granular crystal solid, vacuum-drying gets 47 parts of faint yellow pyromellitic acid anhydride crystalline products, product yield 94%, purity 99.15%.
Embodiment 5
In the 500mL four-hole bottle, add 30 parts of 270 parts of acetic acid and acetic anhydride, be mixed with acetic acid/acetic anhydride mixed solvent, stirred down in 10～30 minutes, be warming up to 60 ℃, add 50 parts of purity and be 98.35% crude product pyromellitic acid anhydride, stirred down, be warming up to 122～124 ℃ reflux temperature in 20～30 minutes, and under this temperature, reacted 5 hours, cooled to below 20 ℃ with water-bath with 2 hours approximately under stirring, filter, obtain the granular crystal solid, vacuum-drying, get 48.5 parts of white or faint yellow pyromellitic acid anhydride crystalline products, product yield 97%, purity 99.02%.
Claims (10)
1. the crystallization granulation of an aromatic tricarboxylic acid anhydride series products and purification process, it is characterized in that described method is: in reactor, add the lower aliphatic carboxylic acid anhydride or contain the mixed solvent of lower aliphatic carboxylic acid anhydride, heating, the many acid anhydrides that in stirring, add crude product aromatic tricarboxylic acid anhydride or aromatic tricarboxylic acid anhydride, many acid anhydrides of cycloaliphatic ring acid anhydrides or cycloaliphatic ring acid anhydrides, a kind of and adsorption decolouriser that is equivalent to above-mentioned material umber 0～50% in many acid anhydrides of heterocycle acid anhydrides or heterocycle acid anhydrides, adsorption 0～10 hour, heat filtering, filtrate concentrates or does not concentrate, cooling, filter, drying makes elaboration aromatic tricarboxylic acid anhydride granular crystal.
2. the crystallization granulation of an aromatic tricarboxylic acid anhydride series products and purification process, it is characterized in that described method is: in reactor, add the lower aliphatic carboxylic acid anhydride or contain the mixed solvent of lower aliphatic carboxylic acid anhydride, stir a kind of in many acid anhydrides of many acid anhydrides, heterocycle acid anhydrides or heterocycle acid anhydrides of the many acid anhydrides, cycloaliphatic ring acid anhydrides or the cycloaliphatic ring acid anhydrides that add crude product aromatic tricarboxylic acid anhydride or aromatic tricarboxylic acid anhydride down, heating, make its part or all of dissolving, the heat effect of boiling 0～10 hour, material concentrates or does not concentrate, cooling, filtration, drying, makes elaboration aromatic tricarboxylic acid anhydride granular crystal.
3. the crystallization granulation of aromatic tricarboxylic acid anhydride series products according to claim 1 and 2 and purification process is characterized in that many acid anhydrides of described aromatic tricarboxylic acid anhydride or aromatic tricarboxylic acid anhydride, many acid anhydrides of cycloaliphatic ring acid anhydrides or cycloaliphatic ring acid anhydrides, many acid anhydrides of heterocycle acid anhydrides or heterocycle acid anhydrides can be in the following material a kind of: pyromellitic acid anhydride, 1,2,3, the 4-pyromellitic dianhydride, 1 (or 2)-carboxyl phthalic anhydride, 1 (or 2)-mono chloro benzene acid anhydride, 1,4-dichloro phthalic anhydride, 2,3-dichloro phthalic anhydride, 1,2,3, the 4-tetrachlorophthalic anhydride, 1 (or 2)-fluorobenzene acid anhydride, 1,4-difluoro phthalic anhydride, 2,3-difluoro phthalic anhydride, 1,2,3,4-tetrafluoro phthalic anhydride, 1 (or 2)-cyano group phthalic anhydride, 1 (or 2)-nitro phthalic anhydride, 3,4,3 ', 4 '-bibenzene tetracarboxylic dianhydride, 2,3,2 ', 3 '-bibenzene tetracarboxylic dianhydride, 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-, 3,4,9, the 10-tetracarboxylic acid dianhydride, 1,2,3,4-encircles glutaric anhydride, 2,3,4,5-tetramethyleneimine dianhydride, 2,3,4, a kind of in the 5-thiophene dianhydride, particularly pyromellitic acid anhydride, 1,2,3, the 4-pyromellitic dianhydride, 3,4,3 ', 4 '-bibenzene tetracarboxylic dianhydride, 2,3,2 ', 3 '-bibenzene tetracarboxylic 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-, 3,4,9, the 10-tetracarboxylic acid dianhydride.
4. the crystallization granulation of aromatic tricarboxylic acid anhydride series products according to claim 1 and 2 and purification process is characterized in that described recrystallization or heat boils solvent and can or contain the mixed solvent of lower aliphatic carboxylic acid anhydride for the lower aliphatic carboxylic acid anhydride; Lower aliphatic carboxylic acid anhydride in the described solvent can be a kind of in a kind of or its mixture in acetic anhydride, propionic anhydride, the Succinic anhydried; Other compositions in the described solvent can be a kind of in a kind of or its mixture in acetate, acetone, butanone, ethyl acetate, ether, benzene, toluene, the tetrahydrofuran (THF); The preferred range that recrystallization or heat are boiled the solvent for use consumption can be aromatic tricarboxylic acid anhydride: solvent is 1 part: 1～20 part, be preferably 1 part: 2～10 parts.
5. the crystallization granulation of aromatic tricarboxylic acid anhydride series products according to claim 1 and 2 and purification process, it is characterized in that consisting of the lower aliphatic carboxylic acid anhydride what described recrystallization or heat were boiled used solvent: other compositions are 0～100 part: 1 part arbitrary proportion.
6. the crystallization granulation of aromatic tricarboxylic acid anhydride series products according to claim 1 and purification process, it is characterized in that sorbent material used in the described recrystallization process can be a kind of in a kind of or its mixture in gac, neutrality or acidic alumina, kaolin, the molecular sieve, is preferably gac; The consumption of described sorbent material can be preferably 1～10% for 0～20% of aromatic tricarboxylic acid anhydride umber.
7. the crystallization granulation of aromatic tricarboxylic acid anhydride series products according to claim 1 and 2 and purification process is characterized in that described recrystallization or heat boils the reflux temperature that the temperature of processing can be from normal temperature to system, are preferably reflux temperature or a little less than reflux temperature.
8. the crystallization granulation of aromatic tricarboxylic acid anhydride series products according to claim 1 and 2 and purification process, it is characterized in that to described recrystallization heat filtering or heat boil obtain after the processing material, can under normal pressure or vacuum, carry out concentration.
9. the crystallization granulation of aromatic tricarboxylic acid anhydride series products according to claim 1 and purification process is characterized in that: the described recrystallization treatment time, the adsorption bleaching time was preferably 0.1～3 hour in order being 0～20 hour.
10. the crystallization granulation of aromatic tricarboxylic acid anhydride series products according to claim 2 and purification process is characterized in that: heat is boiled the treatment time and can be 0～20 hour, is preferably 0.1～5 hour.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103435628A (en) * | 2013-09-09 | 2013-12-11 | 黑龙江省科学院石油化学研究院 | Purification method of benzenetetracarboxylic anhydride |
| CN113527240A (en) * | 2021-07-19 | 2021-10-22 | 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 |
-
2004
- 2004-06-04 CN CNB2004100194817A patent/CN100506778C/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103435628A (en) * | 2013-09-09 | 2013-12-11 | 黑龙江省科学院石油化学研究院 | Purification method of benzenetetracarboxylic anhydride |
| CN113527240A (en) * | 2021-07-19 | 2021-10-22 | 绍兴华为化工有限公司 | Refining process of tetrachlorophthalic anhydride |
| 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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