CN109180504B - Recovery treatment method of 4,4' -diaminodiphenyl ether sublimation residue - Google Patents
Recovery treatment method of 4,4' -diaminodiphenyl ether sublimation residue Download PDFInfo
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- CN109180504B CN109180504B CN201810949797.8A CN201810949797A CN109180504B CN 109180504 B CN109180504 B CN 109180504B CN 201810949797 A CN201810949797 A CN 201810949797A CN 109180504 B CN109180504 B CN 109180504B
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- C07C213/00—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton
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Abstract
The invention relates to the technical field of recovery of fine chemical organic materials, in particular to a recovery treatment method of 4,4' -diaminodiphenyl ether sublimation residues. According to the method for recycling the 4,4 '-diaminodiphenyl ether sublimation residue, 4' -diaminodiphenyl ether in the 4,4 '-diaminodiphenyl ether sublimation residue which is directly treated as hazardous waste originally is recycled, the recovery rate is up to 95.625%, the purity of the recycled 4,4' -diaminodiphenyl ether is up to 99.78%, resources are saved, resource recycling is realized, and the treatment cost of the hazardous waste is effectively reduced.
Description
Technical Field
The invention relates to the technical field of recovery of fine chemical organic materials, in particular to a recovery treatment method of 4,4' -diaminodiphenyl ether sublimation residues.
Background
4,4' -diaminodiphenyl ether (commonly called diamine) is a fine chemical product with high added value, namely ODA for short, with molecular weight of 200.24, white or light yellow crystal, tasteless, melting point of 189-191 ℃ and flash point of 218 ℃. 4,4' -diaminodiphenyl ether is mainly used for the preparation of heat-resistant plastics such as polyimide resins, polymaleimide resins, polyamideimide resins, polyesterimide resins, epoxy resins, polyurethanes, etc., and also as a crosslinking agent. The epoxy resin curing agent has high thermal deformation temperature of cured product, good thermal stability, and excellent chemical resistance and water resistance. And is also a raw material for heat-resistant plastic polyamideimide resins, polyesterimide resins, polyimide resins, polymaleimide resins, and the like.
The production process of 4,4' -diaminodiphenyl ether is as follows: 1. 4,4' -dinitrodiphenyl ether and solvent are put into a hydrogenation reaction kettle, hydrogenation reaction is carried out at the temperature of more than 60 ℃ under the action of palladium-carbon catalyst to generate 4,4' -diaminodiphenyl ether, crude 4,4' -diaminodiphenyl ether is obtained through the working procedures of crystallization, filtration and the like, because the crude 4,4 '-diaminodiphenyl ether has more impurities and can not be directly used as a finished product, the crude 4,4' -diaminodiphenyl ether must be purified by sublimation, the product appearance purity can meet the qualified requirement, the temperature of sublimation operation needs more than 200 ℃, due to factors such as oxidation and the like, about 10 percent of black residue is generated at the bottom of the sublimation kettle, in the prior art, the residues are treated as hazardous wastes, but because the residue contains about 40 percent of 4,4' -diaminodiphenyl ether, the residues directly serve as the hazardous wastes to cause resource waste, and the economic loss generated by the resources is huge every year.
Disclosure of Invention
The invention aims to provide a method for recovering and treating 4,4 '-diaminodiphenyl ether sublimation residues, which overcomes the defects of resource waste and economic loss caused by directly treating the residues after sublimation as hazardous wastes in the prior art, provides a high-efficiency extraction and recovery method of 4,4' -diaminodiphenyl ether in the residues, and reduces the treatment cost of the hazardous wastes.
The technical scheme adopted by the invention for solving the technical problems is as follows: a method for recovering and treating 4,4' -diaminodiphenyl ether sublimation residue comprises the following steps:
(1) crushing residues generated at the bottom of a reaction kettle after sublimation of crude 4,4' -diaminodiphenyl ether into fragments with the granularity of less than 5 cm;
(2) adding N, N-dimethylacetamide into a 2-cubic reaction kettle, starting stirring, adding the crushed residue obtained in the step (1) into the reaction kettle while stirring, heating to 60 ℃, introducing nitrogen for protection, continuously stirring for 1-3 hours until the residue is dissolved, and completely dissolving 4,4' -diaminodiphenyl ether, wherein the weight ratio of the added N, N-dimethylacetamide to the crushed residue is 5: 1-3;
(3) pumping the liquid in the reaction kettle in the step (2) into a filter press for filtering, treating filter cakes as hazardous wastes, feeding the filtrate into another reaction kettle, adding tap water into the reaction kettle according to the proportion of 1:1, mixing the filtrate with water, placing the mixed solution into a centrifuge for centrifugal treatment when the temperature is reduced to 25 ℃, feeding the centrifuged filtrate into a distillation tower for recovering N, N-dimethylacetamide, and obtaining the filter cakes, namely the recovered 4,4' -diaminodiphenyl ether;
(4) putting the 4,4' -diaminodiphenyl ether filter cake recovered in the step (3) into a vacuum drier, introducing steam of 0.1-0.2Mpa into a drier jacket, sealing the drier, vacuumizing to a vacuum degree of less than or equal to-0.08 Mpa, and drying for 1-3 hours to obtain a dried crude product;
(5) and (4) placing the dried crude product in the step (4) into a sublimation kettle for sublimation and purification, controlling the temperature of the sublimation kettle at 205-220 ℃, controlling the vacuum degree at-0.09 Mpa or less, and sublimating for 3-8 hours to obtain the recovered 4,4' -diaminodiphenyl ether.
Preferably, in the step (2), the weight ratio of the N, N-dimethylacetamide to the residue pieces is 5: 2.
Preferably, in the step (2), the temperature is raised to 60 ℃, the reaction kettle is flushed with nitrogen for protection, and stirring is continued for 2 hours.
Preferably, in the step (3), the vacuum degree of the distillation tower is less than or equal to-0.08 Mpa, the temperature of the tower bottom is 110-.
Preferably, in the step (4), the drying is performed in a vacuum dryer for 2 hours.
Preferably, in the step (4), the mixture is sublimated in a sublimation kettle for 5 hours.
The invention has the beneficial effects that: compared with the prior art, the method for recovering and treating 4,4 '-diaminodiphenyl ether sublimation residues recycles 4,4' -diaminodiphenyl ether in the 4,4 '-diaminodiphenyl ether sublimation residues which are directly treated as hazardous wastes originally, the recovery rate is up to 95.625%, the purity of the recovered 4,4' -diaminodiphenyl ether is up to 99.78%, resources are saved, the resources are recycled, and the treatment cost of the hazardous wastes is effectively reduced.
Detailed Description
Example 1
A method for recovering and treating 4,4' -diaminodiphenyl ether sublimation residue comprises the following steps:
(1) crushing residues generated at the bottom of a reaction kettle after sublimation of crude 4,4' -diaminodiphenyl ether into fragments with the granularity of less than 5 cm;
(2) putting 1000 kg of N, N-dimethylacetamide into a 2-cubic reaction kettle, starting stirring, putting 400 kg of residue fragments obtained by crushing in the step (1) into the reaction kettle while stirring, heating to 60 ℃, introducing nitrogen into the reaction kettle for protection, continuously stirring for 2 hours, dissolving the residues, and completely dissolving the 4,4' -diaminodiphenyl ether;
(3) pumping the liquid in the reaction kettle in the step (2) into a filter press for filtering, treating a filter cake as hazardous waste, feeding the filtrate into another reaction kettle, adding tap water into the reaction kettle according to the proportion of 1:1, mixing the filtrate with water, placing the mixed solution into a centrifuge for centrifugal treatment when the temperature is reduced to 25 ℃, feeding the centrifuged filtrate into a distillation tower for recovering N, N-dimethylacetamide, wherein the vacuum degree of the distillation tower is less than or equal to-0.08 MPa, the temperature of the tower kettle is 110 and 130 ℃, the temperature of the tower top is 65-70 ℃, and the obtained filter cake is the recovered 4,4' -diaminodiphenyl ether;
(4) putting the 4,4' -diaminodiphenyl ether filter cake recovered in the step (3) into a vacuum drier, introducing steam of 0.1-0.2Mpa into a drier jacket, sealing the drier, vacuumizing, and drying for 2 hours to obtain a dried crude product, wherein the vacuum degree is less than or equal to-0.08 Mpa;
(5) and (4) placing the dried crude product in the step (4) into a sublimation kettle for sublimation and purification, controlling the temperature of the sublimation kettle at 205-220 ℃, controlling the vacuum degree at-0.09 Mpa or less, and sublimating for 5 hours to obtain the recovered 4,4' -diaminodiphenyl ether.
Example 2
A method for recovering and treating 4,4' -diaminodiphenyl ether sublimation residue comprises the following steps:
(1) crushing residues generated at the bottom of a reaction kettle after sublimation of crude 4,4' -diaminodiphenyl ether into fragments with the granularity of less than 5 cm;
(2) putting 1000 kg of N, N-dimethylacetamide into a 2-cubic reaction kettle, starting stirring, putting 400 kg of residue fragments obtained by crushing in the step (1) into the reaction kettle while stirring, heating to 60 ℃, introducing nitrogen into the reaction kettle for protection, continuously stirring for 1.5 hours until the residues are dissolved, and completely dissolving the 4,4' -diaminodiphenyl ether;
(3) pumping the liquid in the reaction kettle in the step (2) into a filter press for filtering, treating a filter cake as hazardous waste, feeding the filtrate into another reaction kettle, adding tap water into the reaction kettle according to the proportion of 1:1, mixing the filtrate with water, placing the mixed solution into a centrifuge for centrifugal treatment when the temperature is reduced to 25 ℃, feeding the centrifuged filtrate into a distillation tower for recovering N, N-dimethylacetamide, wherein the vacuum degree of the distillation tower is less than or equal to-0.08 MPa, the temperature of the tower kettle is 110 and 130 ℃, the temperature of the tower top is 65-70 ℃, and the obtained filter cake is the recovered 4,4' -diaminodiphenyl ether;
(4) putting the 4,4' -diaminodiphenyl ether filter cake recovered in the step (3) into a vacuum drier, introducing steam of 0.1-0.2Mpa into a drier jacket, sealing the drier, vacuumizing, and drying for 1 hour to obtain a dried crude product, wherein the vacuum degree is less than or equal to-0.08 Mpa;
(5) and (4) placing the dried crude product in the step (4) into a sublimation kettle for sublimation and purification, controlling the temperature of the sublimation kettle at 205-220 ℃, controlling the vacuum degree at-0.09 Mpa or less, and sublimating for 3 hours to obtain the recovered 4,4' -diaminodiphenyl ether.
Example 3
A method for recovering and treating 4,4' -diaminodiphenyl ether sublimation residue comprises the following steps:
(1) crushing residues generated at the bottom of a reaction kettle after sublimation of crude 4,4' -diaminodiphenyl ether into fragments with the granularity of less than 5 cm;
(2) putting 1000 kg of N, N-dimethylacetamide into a 2-cubic reaction kettle, starting stirring, putting 400 kg of residue fragments obtained by crushing in the step (1) into the reaction kettle while stirring, heating to 60 ℃, introducing nitrogen into the reaction kettle for protection, continuously stirring for 3 hours, dissolving the residues, and completely dissolving the 4,4' -diaminodiphenyl ether;
(3) pumping the liquid in the reaction kettle in the step (2) into a filter press for filtering, treating a filter cake as hazardous waste, feeding the filtrate into another reaction kettle, adding tap water into the reaction kettle according to the proportion of 1:1, mixing the filtrate with water, placing the mixed solution into a centrifuge for centrifugal treatment when the temperature is reduced to 25 ℃, feeding the centrifuged filtrate into a distillation tower for recovering N, N-dimethylacetamide, wherein the vacuum degree of the distillation tower is less than or equal to-0.08 MPa, the temperature of the tower kettle is 110 and 130 ℃, the temperature of the tower top is 65-70 ℃, and the obtained filter cake is the recovered 4,4' -diaminodiphenyl ether;
(4) putting the 4,4' -diaminodiphenyl ether filter cake recovered in the step (3) into a vacuum drier, introducing steam of 0.1-0.2Mpa into a drier jacket, sealing the drier, vacuumizing, and drying for 3 hours to obtain a dried crude product, wherein the vacuum degree is less than or equal to-0.08 Mpa;
(5) and (4) placing the dried crude product in the step (4) into a sublimation kettle for sublimation and purification, controlling the temperature of the sublimation kettle at 205-220 ℃, controlling the vacuum degree at-0.09 Mpa or less, and sublimating for 4 hours to obtain the recovered 4,4' -diaminodiphenyl ether.
Examples of the experiments
The contents of 4,4 '-diaminodiphenyl ether in the sublimation residue in examples 1 to 3 were all 40%, and the purity of 4,4' -diaminodiphenyl ether recovered in step (3) in examples 1 to 3 was determined by gas chromatography and was designated as N1; the purity of the 4,4' -diaminodiphenyl ether recovered in the step (5) in the examples 1 to 3 is detected by gas chromatography and is marked as N2; the crude products recovered in step (4) of examples 1-3 were weighed and recorded as M1; the 4,4' -diaminodiphenyl ether recovered in step (5) in examples 1-3 was weighed and reported as M2. The specific test results are shown in table 1:
TABLE 1
| Group of | N1（%） | N2（%） | M1（kg） | M2（kg） | Recovery (%) |
| Example 1 | 99.23 | 99.78 | 170 | 153 | 95.625 |
| Example 2 | 99.08 | 99.59 | 160 | 145 | 90.625 |
| Example 3 | 99.12 | 99.63 | 164 | 147 | 91.875 |
It can be seen from table 1 that, by using the method for recovering and treating 4,4' -diaminodiphenyl ether sublimation residue of the present invention, 4' -diaminodiphenyl ether in about 10% of black residue generated at the bottom of a sublimation kettle can be effectively recovered, with a recovery rate of > 90%, and particularly, by using the method for recovering and treating 4,4' -diaminodiphenyl ether sublimation residue of example 1, the recovery rate of 4,4' -diaminodiphenyl ether can be as high as 95.294%, and the purity of the recovered 4,4' -diaminodiphenyl ether can be as high as 99.78%.
The above embodiments are only specific examples of the present invention, and the protection scope of the present invention includes but is not limited to the product forms and styles of the above embodiments, and any suitable changes or modifications made by those skilled in the art according to the claims of the present invention shall fall within the protection scope of the present invention.
Claims (6)
1. A method for recovering and treating 4,4' -diaminodiphenyl ether sublimation residue is characterized by comprising the following steps: the method comprises the following steps:
(1) crushing residues generated at the bottom of a reaction kettle after the crude 4,4' -diaminodiphenyl ether is sublimated into fragments with the granularity of less than 5 cm;
(2) adding N, N-dimethylacetamide into a 2-cubic reaction kettle, starting stirring, adding the crushed residue obtained by crushing in the step (1) into the reaction kettle while stirring, heating to 60 ℃, introducing nitrogen for protection, continuously stirring for 1-3 hours until the residue is dissolved, and completely dissolving 4,4' -diaminodiphenyl ether, wherein the weight ratio of the added N, N-dimethylacetamide to the crushed residue is 5: 1-3;
(3) pumping the liquid in the reaction kettle in the step (2) into a filter press for filtering, treating filter cakes as hazardous wastes, feeding the filtrate into another reaction kettle, adding tap water into the reaction kettle according to the proportion of 1:1, mixing the filtrate with water, placing the mixed solution into a centrifuge for centrifugal treatment when the temperature is reduced to 25 ℃, feeding the centrifuged filtrate into a distillation tower for recovering N, N-dimethylacetamide, and obtaining the filter cakes, namely the recovered 4,4' -diaminodiphenyl ether;
(4) putting the 4,4' -diaminodiphenyl ether filter cake recovered in the step (3) into a vacuum drier, introducing steam of 0.1-0.2Mpa into a drier jacket, sealing the drier, vacuumizing to the vacuum degree of less than or equal to-0.08 Mpa, and drying for 1-3 hours to obtain a dried crude product;
(5) and (4) placing the dried crude product in the step (4) into a sublimation kettle for sublimation purification, controlling the temperature of the sublimation kettle at 205-220 ℃, controlling the vacuum degree at less than or equal to-0.09 Mpa, and sublimating for 3-8 hours to obtain the recovered 4,4' -diaminodiphenyl ether.
2. The method for recycling and treating 4,4' -diaminodiphenyl ether sublimation residue as claimed in claim 1, characterized in that: in the step (2), the weight ratio of the N, N-dimethylacetamide to the residue fragments is 5: 2.
3. The method for recycling and treating 4,4' -diaminodiphenyl ether sublimation residue as claimed in claim 1, characterized in that: and (3) heating to 60 ℃ in the step (2), introducing nitrogen into the reaction kettle for protection, and continuing stirring for 2 hours.
4. The method for recycling and treating 4,4' -diaminodiphenyl ether sublimation residue as claimed in claim 1, characterized in that: in the step (3), the vacuum degree of the distillation tower is less than or equal to-0.08 Mpa, the temperature of the tower bottom is 110-.
5. The method for recycling and treating 4,4' -diaminodiphenyl ether sublimation residue as claimed in claim 1, characterized in that: in the step (4), drying is carried out in a vacuum dryer for 2 hours.
6. The method for recycling and treating 4,4' -diaminodiphenyl ether sublimation residue as claimed in claim 1, characterized in that: in the step (5), the mixture is sublimated in a sublimation kettle for 5 hours.
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| CN110015965A (en) * | 2019-04-26 | 2019-07-16 | 山东欧亚化工有限公司 | A method of 4,4 '-diaminodiphenyl ether secondary crystallizations of production |
| CN110041211A (en) * | 2019-04-26 | 2019-07-23 | 山东欧亚化工有限公司 | A kind of recovery and treatment method of 4,4 '-diaminodiphenyl ether rectifying still bottom residues |
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