CN109180504A - A kind of recovery and treatment method of 4,4`- diaminodiphenyl ether distillation residue - Google Patents
A kind of recovery and treatment method of 4,4`- diaminodiphenyl ether distillation residue Download PDFInfo
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- CN109180504A CN109180504A CN201810949797.8A CN201810949797A CN109180504A CN 109180504 A CN109180504 A CN 109180504A CN 201810949797 A CN201810949797 A CN 201810949797A CN 109180504 A CN109180504 A CN 109180504A
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- diaminodiphenyl ether
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- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- 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
- C07C213/10—Separation; Purification; Stabilisation; Use of additives
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Abstract
The present invention relates to the recovery technology fields of fine chemistry industry organic material, the especially recovery and treatment method of one kind 4,4'- diaminodiphenyl ether distillation residue.One kind 4 of the invention, the recovery and treatment method of 4'- diaminodiphenyl ether distillation residue, 4, the 4'- diaminodiphenyl ether in 4,4'- diaminodiphenyl ether distillation residue that script is handled directly as dangerous waste recycles herein, the rate of recovery is up to 95.625%, it recycles obtained 4,4'- diaminodiphenyl ether purity and is up to 99.78%, not only saved resource, it realizes that resource reclaim recycles, and effectively reduces the processing cost of dangerous waste.
Description
Technical field
The present invention relates to the recovery technology fields of fine chemistry industry organic material, especially one kind 4,4'- diaminodiphenyl ether
The recovery and treatment method of distillation residue.
Background technique
4,4'- diaminodiphenyl ethers (being commonly called as diamines) are a kind of fine chemical product of high added value, abbreviation ODA, molecule
Amount 200.24, white or Light yellow crystals, it is tasteless, 189~191 DEG C of fusing point, 218 DEG C of flash-point.4,4'- diaminodiphenyl ether is main
It is used to prepare heat-resistant plastic such as polyimide resin, polymaleimide resins, polyamide-imide resin, polyesterimide
Resin, epoxy resin, polyurethane etc., also serve as crosslinking agent.Curing agent as epoxy resin, solidfied material heat distortion temperature is high,
Thermostabilization is good, and chemical resistance and water resistance are excellent.It is also heat-resisting plastic polyamide imide resin, polyester acyl
The raw material of imide resin, polyimide resin, polymaleimide resins etc..
The production process of 4,4'- diaminodiphenyl ether is as follows: 1,4,4'- dinitro diphenyl ether and solvent put into hydrogenation reaction
In kettle, under 60 DEG C or more, palladium-carbon catalyst effect, hydrogenation reaction generates 4,4'- diaminodiphenyl ether, by crystallizing, filtering
Etc. processes, obtain thick 4,4'- diaminodiphenyl ether, since thick 4,4'- diaminodiphenyl ether impurity is more, can not directly as at
Product use, it is necessary to which after sublimation purification, product appearance purity can be only achieved Eligibility requirements, and distillation operation needs 200 DEG C or more
Temperature, due to factors such as oxidations, distillation bottom can generate 10% or so black residue, these residues are made in the prior art
It is handled for dangerous waste, but due to 4, the 4'- diaminodiphenyl ether in residue ingredient containing 40% or so, directly as dangerous waste processing
When result in waste of resources, annual resulting economic loss is huge.
Summary of the invention
The purpose of the present invention is to provide the recovery and treatment methods of one kind 4,4'- diaminodiphenyl ether distillation residue, overcome
Residue after aforementioned distillation in the prior art causes the deficiency of the wasting of resources and economic loss directly as dangerous waste processing, proposes
The high efficiency extraction recovering means of 4,4'- diaminodiphenyl ether in residue, and reduce the processing cost of dangerous waste.
The technical scheme adopted by the invention to solve the technical problem is that: a kind of 4,4'- diaminodiphenyl ether distillation residue
Recovery and treatment method, include the following steps:
(1) residue that the bottom of reaction kettle after the distillation of thick 4,4'- diaminodiphenyl ether generates is broken into granularity and is less than the broken of 5cm
Block；
(2) in 2 cubes of reaction kettle, n,N-dimethylacetamide is put into, stirring is opened, is put into while stirring into reaction kettle
The broken obtained residue fragment of step (1), the n,N-dimethylacetamide of investment and the weight ratio of residue fragment are 5:1-3, are risen
For temperature to 60 DEG C, reaction kettle rushes nitrogen protection, continues stirring 1-3 hours, and residue dissolves, and 4,4'- diaminodiphenyl ethers all dissolve；
(3) liquid in the reaction kettle of step (2) is pumped into filter press and is filtered, filter cake enters another as dangerous waste processing, filtrate
Tap water is added into reaction kettle according to the ratio of 1:1 in one reaction kettle, filtrate mixed with water after when temperature drops to 25 DEG C,
Mixed liquor is put into centrifuge and carries out centrifugal treating, the filtrate after centrifugation recycles n,N-dimethylacetamide into destilling tower, obtains
Filter cake be recycle 4,4 '-diaminodiphenyl ethers；
(4) 4, the 4 '-diaminodiphenyl ether filter cakes recycled in step (3) are placed in vacuum drier, drying machine collet is passed through
The steam of 0.1-0.2Mpa, hermetically drying machine vacuumize, vacuum degree≤- 0.08Mpa, dry 1-3 hours, obtain dried thick
Product；
(5) crude product dried in step (4) is placed in sublimation purification in distillation kettle again, distillation kettle temperature degree control is in 205-220
DEG C, vacuum degree control distils 3-8 hours in≤- 0.09Mpa to get after the recovery 4,4 '-diaminodiphenyl ethers.
Preferably, in the step (2), the n,N-dimethylacetamide of investment and the weight ratio of residue fragment are 5:2.
Preferably, 60 DEG C are warming up in the step (2), reaction kettle rushes nitrogen protection, continues stirring 2 hours.
Preferably, in the step (3), destilling tower vacuum degree≤- 0.08Mpa, bottom temperature is 110-130 DEG C, tower top
Temperature is 65-70 DEG C.
Preferably, 2 hours dry in vacuum drier in the step (4).
Preferably, it in the step (4), distils 5 hours in distillation kettle.
The beneficial effects of the present invention are: compared with prior art, one kind 4,4'- diaminodiphenyl ether distillation of the invention is residual
The recovery and treatment method of slag, 4, the 4'- bis- in 4,4'- diaminodiphenyl ether distillation residue that script is handled directly as dangerous waste
Amino-diphenylethers recycles herein, and the rate of recovery is up to 95.625%, and 4, the 4'- diaminodiphenyl ether purity recycled is up to
99.78%, resource has not only been saved, has realized that resource reclaim recycles, and effectively reduce the processing cost of dangerous waste.
Specific embodiment
Embodiment 1
The recovery and treatment method of one kind 4,4'- diaminodiphenyl ether distillation residue, includes the following steps:
(1) residue that the bottom of reaction kettle after the distillation of thick 4,4'- diaminodiphenyl ether generates is broken into granularity and is less than the broken of 5cm
Block；
(2) in 2 cubes of reaction kettle, 1000 kilograms of n,N-dimethylacetamide are put into, stirring are opened, while stirring to reaction
Step (1) broken 400 kilograms of residue fragment obtained are put into kettle, are warming up to 60 DEG C, reaction kettle rushes nitrogen protection, continues to stir
2 hours, residue dissolved, and 4,4'- diaminodiphenyl ethers all dissolve；
(3) liquid in the reaction kettle of step (2) is pumped into filter press and is filtered, filter cake enters another as dangerous waste processing, filtrate
Tap water is added into reaction kettle according to the ratio of 1:1 in one reaction kettle, filtrate mixed with water after when temperature drops to 25 DEG C,
Mixed liquor is put into centrifuge and carries out centrifugal treating, the filtrate after centrifugation recycles n,N-dimethylacetamide, distillation into destilling tower
Tower vacuum degree≤- 0.08Mpa, bottom temperature are 110-130 DEG C, and tower top temperature is 65-70 DEG C, and obtained filter cake is to recycle
4,4 '-diaminodiphenyl ethers；
(4) 4, the 4 '-diaminodiphenyl ether filter cakes recycled in step (3) are placed in vacuum drier, drying machine collet is passed through
The steam of 0.1-0.2Mpa, hermetically drying machine vacuumize, vacuum degree≤- 0.08Mpa, dry 2 hours, obtain dried thick
Product；
(5) crude product dried in step (4) is placed in sublimation purification in distillation kettle again, distillation kettle temperature degree control is in 205-220
DEG C, vacuum degree control distils 5 hours in≤- 0.09Mpa to get after the recovery 4,4 '-diaminodiphenyl ethers.
Embodiment 2
The recovery and treatment method of one kind 4,4'- diaminodiphenyl ether distillation residue, includes the following steps:
(1) residue that the bottom of reaction kettle after the distillation of thick 4,4'- diaminodiphenyl ether generates is broken into granularity and is less than the broken of 5cm
Block；
(2) in 2 cubes of reaction kettle, 1000 kilograms of n,N-dimethylacetamide are put into, stirring are opened, while stirring to reaction
Step (1) broken 400 kilograms of residue fragment obtained are put into kettle, are warming up to 60 DEG C, reaction kettle rushes nitrogen protection, continues to stir
1.5 hours, residue dissolved, and 4,4'- diaminodiphenyl ethers all dissolve；
(3) liquid in the reaction kettle of step (2) is pumped into filter press and is filtered, filter cake enters another as dangerous waste processing, filtrate
Tap water is added into reaction kettle according to the ratio of 1:1 in one reaction kettle, filtrate mixed with water after when temperature drops to 25 DEG C,
Mixed liquor is put into centrifuge and carries out centrifugal treating, the filtrate after centrifugation recycles n,N-dimethylacetamide, distillation into destilling tower
Tower vacuum degree≤- 0.08Mpa, bottom temperature are 110-130 DEG C, and tower top temperature is 65-70 DEG C, and obtained filter cake is to recycle
4,4 '-diaminodiphenyl ethers；
(4) 4, the 4 '-diaminodiphenyl ether filter cakes recycled in step (3) are placed in vacuum drier, drying machine collet is passed through
The steam of 0.1-0.2Mpa, hermetically drying machine vacuumize, vacuum degree≤- 0.08Mpa, dry 1 hour, obtain dried thick
Product；
(5) crude product dried in step (4) is placed in sublimation purification in distillation kettle again, distillation kettle temperature degree control is in 205-220
DEG C, vacuum degree control distils 3 hours in≤- 0.09Mpa to get after the recovery 4,4 '-diaminodiphenyl ethers.
Embodiment 3
The recovery and treatment method of one kind 4,4'- diaminodiphenyl ether distillation residue, includes the following steps:
(1) residue that the bottom of reaction kettle after the distillation of thick 4,4'- diaminodiphenyl ether generates is broken into granularity and is less than the broken of 5cm
Block；
(2) in 2 cubes of reaction kettle, 1000 kilograms of n,N-dimethylacetamide are put into, stirring are opened, while stirring to reaction
Step (1) broken 400 kilograms of residue fragment obtained are put into kettle, are warming up to 60 DEG C, reaction kettle rushes nitrogen protection, continues to stir
3 hours, residue dissolved, and 4,4'- diaminodiphenyl ethers all dissolve；
(3) liquid in the reaction kettle of step (2) is pumped into filter press and is filtered, filter cake enters another as dangerous waste processing, filtrate
Tap water is added into reaction kettle according to the ratio of 1:1 in one reaction kettle, filtrate mixed with water after when temperature drops to 25 DEG C,
Mixed liquor is put into centrifuge and carries out centrifugal treating, the filtrate after centrifugation recycles n,N-dimethylacetamide, distillation into destilling tower
Tower vacuum degree≤- 0.08Mpa, bottom temperature are 110-130 DEG C, and tower top temperature is 65-70 DEG C, and obtained filter cake is to recycle
4,4 '-diaminodiphenyl ethers；
(4) 4, the 4 '-diaminodiphenyl ether filter cakes recycled in step (3) are placed in vacuum drier, drying machine collet is passed through
The steam of 0.1-0.2Mpa, hermetically drying machine vacuumize, vacuum degree≤- 0.08Mpa, dry 3 hours, obtain dried thick
Product；
(5) crude product dried in step (4) is placed in sublimation purification in distillation kettle again, distillation kettle temperature degree control is in 205-220
DEG C, vacuum degree control distils 4 hours in≤- 0.09Mpa to get after the recovery 4,4 '-diaminodiphenyl ethers.
Experimental example 1
4,4'- diaminodiphenyl ether content is 40% in distillation residue in embodiment 1-3, and step (3) recycles in embodiment 1-3
4,4'- diaminodiphenyl ether with gas chromatography detect purity, be denoted as N1；Step (5) after the recovery 4 in embodiment 1-3,
4 '-diaminodiphenyl ethers detect purity with gas chromatography, are denoted as N2；The crude product that step (4) recycles in embodiment 1-3 claims
Weight, is denoted as M1；4, the 4 '-diaminodiphenyl ethers that step (5) recycles in embodiment 1-3 are weighed, and M2 is denoted as.Specific test result
It is as shown in table 1:
Table 1
| Group | N1(%) | N2(%) | M1(kg) | M2(kg) | The rate of recovery (%) |
| Embodiment 1 | 99.23 | 99.78 | 170 | 153 | 95.625 |
| Embodiment 2 | 99.08 | 99.59 | 160 | 145 | 90.625 |
| Embodiment 3 | 99.12 | 99.63 | 164 | 147 | 91.875 |
There is table 1 as can be seen that using the recovery and treatment method of one kind 4,4'- diaminodiphenyl ether distillation residue of the invention, energy
Enough 4,4'- diaminodiphenyl ethers by 10% or so the black residue that bottom can generate that distils effectively recycle, rate of recovery >
90%, in particular by the recovery and treatment method of 4, the 4'- diaminodiphenyl ether distillation residue in embodiment 1, make 4,4'- diamino
The yl diphenyl ether rate of recovery is up to 95.294%, and 4, the 4'- diaminodiphenyl ether purity recycled is up to 99.78%, this effect table
A kind of recovery and treatment method of bright 4,4'- diaminodiphenyl ether distillation residue of the invention can in high efficiente callback residue 4,
4'- diaminodiphenyl ether, and reduce the processing cost of dangerous waste.
Above-mentioned specific embodiment is only specific case of the invention, and scope of patent protection of the invention includes but is not limited to
The product form and style of above-mentioned specific embodiment, any claims of the present invention and any technical field of meeting
The appropriate changes or modifications that those of ordinary skill does it, all shall fall within the protection scope of the present invention.
Claims (6)
1. one kind 4, the recovery and treatment method of 4'- diaminodiphenyl ether distillation residue, characterized by the following steps:
The residue that the bottom of reaction kettle after the distillation of thick 4,4'- diaminodiphenyl ether generates is broken into the fragment that granularity is less than 5cm；
In 2 cubes of reaction kettle, n,N-dimethylacetamide is put into, opens stirring, puts into step into reaction kettle while stirring
Suddenly (1) broken obtained residue fragment, the n,N-dimethylacetamide of investment and the weight ratio of residue fragment are 5:1-3, heating
To 60 DEG C, reaction kettle rushes nitrogen protection, continues stirring 1-3 hours, and residue dissolves, and 4,4'- diaminodiphenyl ethers all dissolve；
Liquid in the reaction kettle of step (2) is pumped into filter press and is filtered, as dangerous waste processing, filtrate enters another anti-filter cake
Answer kettle, be added tap water into reaction kettle according to the ratio of 1:1, filtrate mixed with water after when temperature drops to 25 DEG C, will mix
It closes liquid and is put into centrifuge progress centrifugal treating, the filtrate after centrifugation recycles n,N-dimethylacetamide, obtained filter into destilling tower
Cake is the 4,4 '-diaminodiphenyl ethers recycled；
4, the 4 '-diaminodiphenyl ether filter cakes recycled in step (3) are placed in vacuum drier, drying machine collet is passed through 0.1-
The steam of 0.2Mpa, hermetically drying machine vacuumize, vacuum degree≤- 0.08Mpa, 1-3 hours dry, obtain dried crude product；
Crude product dried in step (4) is placed in sublimation purification in distillation kettle again, distillation kettle temperature degree is controlled at 205-220 DEG C,
Vacuum degree control distils 3-8 hours in≤- 0.09Mpa to get after the recovery 4,4 '-diaminodiphenyl ethers.
2. the recovery and treatment method of one kind 4,4'- diaminodiphenyl ether distillation residue as described in claim 1, feature exist
In: in the step (2), the n,N-dimethylacetamide of investment and the weight ratio of residue fragment are 5:2.
3. the recovery and treatment method of one kind 4,4'- diaminodiphenyl ether distillation residue as described in claim 1, feature exist
In: 60 DEG C are warming up in the step (2), reaction kettle rushes nitrogen protection, continues stirring 2 hours.
4. the recovery and treatment method of one kind 4,4'- diaminodiphenyl ether distillation residue as described in claim 1, feature exist
In: in the step (3), destilling tower vacuum degree≤- 0.08Mpa, bottom temperature is 110-130 DEG C, tower top temperature 65-70
℃。
5. the recovery and treatment method of one kind 4,4'- diaminodiphenyl ether distillation residue as described in claim 1, feature exist
In: it is 2 hours dry in vacuum drier in the step (4).
6. the recovery and treatment method of one kind 4,4'- diaminodiphenyl ether distillation residue as described in claim 1, feature exist
In: in the step (4), distil 5 hours in distillation kettle.
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Cited By (2)
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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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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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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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