CN112341345A - Method and system for extracting 4,4' -diaminodiphenyl ether from DMAC (dimethylacetamide) medium - Google Patents
Method and system for extracting 4,4' -diaminodiphenyl ether from DMAC (dimethylacetamide) medium Download PDFInfo
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- CN112341345A CN112341345A CN202010838620.8A CN202010838620A CN112341345A CN 112341345 A CN112341345 A CN 112341345A CN 202010838620 A CN202010838620 A CN 202010838620A CN 112341345 A CN112341345 A CN 112341345A
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- HLBLWEWZXPIGSM-UHFFFAOYSA-N 4-Aminophenyl ether Chemical compound C1=CC(N)=CC=C1OC1=CC=C(N)C=C1 HLBLWEWZXPIGSM-UHFFFAOYSA-N 0.000 title claims abstract description 67
- 238000000034 method Methods 0.000 title claims abstract description 33
- FXHOOIRPVKKKFG-UHFFFAOYSA-N N,N-Dimethylacetamide Chemical compound CN(C)C(C)=O FXHOOIRPVKKKFG-UHFFFAOYSA-N 0.000 title abstract description 60
- 238000005984 hydrogenation reaction Methods 0.000 claims abstract description 107
- 238000001816 cooling Methods 0.000 claims abstract description 106
- 239000003054 catalyst Substances 0.000 claims abstract description 38
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 29
- 239000007788 liquid Substances 0.000 claims abstract description 28
- 239000002904 solvent Substances 0.000 claims abstract description 28
- 238000001914 filtration Methods 0.000 claims abstract description 22
- 239000002826 coolant Substances 0.000 claims abstract description 15
- 239000007787 solid Substances 0.000 claims abstract description 9
- 150000001298 alcohols Chemical class 0.000 claims abstract description 4
- 239000000463 material Substances 0.000 claims description 37
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 claims description 28
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 20
- MWAGUKZCDDRDCS-UHFFFAOYSA-N 1-nitro-4-(4-nitrophenoxy)benzene Chemical compound C1=CC([N+](=O)[O-])=CC=C1OC1=CC=C([N+]([O-])=O)C=C1 MWAGUKZCDDRDCS-UHFFFAOYSA-N 0.000 claims description 19
- 238000004519 manufacturing process Methods 0.000 claims description 12
- 238000003860 storage Methods 0.000 claims description 11
- 238000006243 chemical reaction Methods 0.000 claims description 10
- 230000008569 process Effects 0.000 claims description 10
- 239000002994 raw material Substances 0.000 claims description 10
- UKVIEHSSVKSQBA-UHFFFAOYSA-N methane;palladium Chemical compound C.[Pd] UKVIEHSSVKSQBA-UHFFFAOYSA-N 0.000 claims description 6
- 238000004321 preservation Methods 0.000 claims description 6
- 239000007810 chemical reaction solvent Substances 0.000 claims description 5
- 238000000605 extraction Methods 0.000 claims description 5
- RTZKZFJDLAIYFH-UHFFFAOYSA-N ether Substances CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 claims description 3
- 238000006555 catalytic reaction Methods 0.000 claims description 2
- MHABMANUFPZXEB-UHFFFAOYSA-N O-demethyl-aloesaponarin I Natural products O=C1C2=CC=CC(O)=C2C(=O)C2=C1C=C(O)C(C(O)=O)=C2C MHABMANUFPZXEB-UHFFFAOYSA-N 0.000 claims 12
- 239000000126 substance Substances 0.000 claims 1
- 239000000047 product Substances 0.000 description 20
- 238000002425 crystallisation Methods 0.000 description 9
- 230000008025 crystallization Effects 0.000 description 9
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 8
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 description 8
- 230000000694 effects Effects 0.000 description 7
- 239000012043 crude product Substances 0.000 description 6
- 229940113088 dimethylacetamide Drugs 0.000 description 6
- 239000000203 mixture Substances 0.000 description 6
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 5
- 238000002360 preparation method Methods 0.000 description 5
- 230000009467 reduction Effects 0.000 description 5
- 239000003507 refrigerant Substances 0.000 description 5
- 238000005265 energy consumption Methods 0.000 description 4
- 238000002844 melting Methods 0.000 description 4
- 230000008018 melting Effects 0.000 description 4
- 229910052757 nitrogen Inorganic materials 0.000 description 4
- 238000000926 separation method Methods 0.000 description 4
- 239000001257 hydrogen Substances 0.000 description 3
- 229910052739 hydrogen Inorganic materials 0.000 description 3
- 238000005086 pumping Methods 0.000 description 3
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 2
- 238000005119 centrifugation Methods 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000012452 mother liquor Substances 0.000 description 2
- 239000003960 organic solvent Substances 0.000 description 2
- 238000005057 refrigeration Methods 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 150000001408 amides Chemical class 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000012847 fine chemical Substances 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000006864 oxidative decomposition reaction Methods 0.000 description 1
- 238000011027 product recovery Methods 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- 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
- C07C213/02—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton by reactions involving the formation of amino groups from compounds containing hydroxy groups or etherified or esterified hydroxy groups
-
- C—CHEMISTRY; METALLURGY
- 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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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The disclosure relates to a method and a system for extracting 4,4 '-diaminodiphenyl ether from DMAC (dimethylacetamide) medium, wherein a hydrogenation solution containing solvents of DMAC, 4' -diaminodiphenyl ether and a hydrogenation catalyst is subjected to hot filtration to remove solids; then, carrying out primary cooling on the hydrogenated liquid, carrying out secondary cooling after the primary cooling, and finally separating to obtain 4,4' -diaminodiphenyl ether; wherein, the primary cooling adopts water as a cooling medium and is reduced to 38-45 ℃; the secondary cooling adopts alcohols as cooling medium, and the temperature is reduced from 38-45 ℃ to 10 ℃ or below. The invention separates 4,4 '-diaminodiphenyl ether in DMAC completely, which makes the yield of primary product reach more than 98%, solves the problem of low yield of extracting 4,4' -diaminodiphenyl ether from DMAC.
Description
Technical Field
The present disclosure relates to a method and system for extracting 4,4' -diaminodiphenyl ether from Dimethylacetamide (DMAC) media.
Background
The information in this background section is disclosed only to enhance an understanding of the general background of the disclosure and is not necessarily to be construed as an admission or any form of suggestion that this information forms the prior art that is already known to a person of ordinary skill in the art.
4,4' -diaminodiphenyl ether is a fine chemical intermediate with high added value. In the production process of 4,4' -diaminodiphenyl ether, the common method is as follows: 4,4' -dinitrodiphenyl ether and solvent DMAC are put into a hydrogenation kettle, hydrogenation reaction is carried out at the temperature of more than 60 ℃ under the action of a catalyst to generate 4,4' -diaminodiphenyl ether, and the crude product of the 4,4' -diaminodiphenyl ether is obtained through the working procedures of crystallization, extraction, filtration, concentration, centrifugation and the like. The main problems of the method are as follows: 4,4 '-diaminodiphenyl ether is easily dissolved in DMAC, the mother liquor still contains about 15 percent of 4,4' -diaminodiphenyl ether after the crystallization is carried out to normal temperature and the centrifugation, and the primary yield is less than 85 percent; when the DMAC is concentrated, the temperature reaches 130-135 ℃,4' -diaminodiphenyl ether in the solvent is easy to oxidize and decompose, the product recovery rate is low, the by-product generated by decomposition is polluted, and the energy consumption is higher.
Disclosure of Invention
In order to overcome the defects in the prior art, the disclosure provides a method and a corresponding system for extracting 4,4' -diaminodiphenyl ether from a DMAC medium, a heating and concentrating process is not adopted in the extraction process, the recovery rate of a primary product is improved to 98%, and the energy efficiency improvement, clean production and cyclic utilization of the traditional manufacturing industry can be realized.
Specifically, the following technical scheme is adopted in the disclosure:
in a first aspect of the disclosure, there is provided a method of extracting 4,4' -diaminodiphenyl ether from DMAC media, the method comprising the steps of:
carrying out hot filtration on hydrogenated liquid containing a solvent DMAC, 4' -diaminodiphenyl ether and a hydrogenation catalyst to remove solids; then, carrying out primary cooling on the hydrogenated liquid, carrying out secondary cooling after the primary cooling, and finally separating to obtain 4,4' -diaminodiphenyl ether;
wherein, the primary cooling adopts water as a cooling medium and is reduced to 38-45 ℃;
the secondary cooling adopts alcohols as cooling medium, and the temperature is reduced from 38-45 ℃ to 10 ℃ or below.
In a second aspect of the present disclosure, there is provided a method for producing 4,4 '-diaminodiphenyl ether, which comprises the method for extracting 4,4' -diaminodiphenyl ether from DMAC medium in the first aspect.
In a third aspect of the disclosure, there is provided a system for extracting 4,4' -diaminodiphenyl ether from DMAC media, comprising:
the hydrogenation kettle, the thermal filtering equipment, the primary cooling kettle and the secondary cooling kettle are sequentially communicated;
the primary cooling kettle comprises a first jacket, and a water inlet pipeline is arranged in the first jacket;
the secondary cooling kettle comprises a second jacket, and an alcohol inlet pipeline is arranged in the second jacket.
In a fourth aspect of the present disclosure, there is provided a system for producing 4,4 '-diaminodiphenyl ether, which comprises a system for extracting 4,4' -diaminodiphenyl ether from DMAC medium in the third aspect.
Compared with the related technology known by the inventor, one technical scheme of the present disclosure has the following beneficial effects:
the invention separates 4,4 '-diaminodiphenyl ether in DMAC completely, which makes the yield of primary product reach more than 98%, solves the problem of low yield of extracting 4,4' -diaminodiphenyl ether from DMAC. The traditional process is completed in one reaction kettle, the temperature rise and the temperature reduction are performed in one set of system for a long time, the damage to equipment is large, the temperature rise is not needed, the temperature reduction is completed in two different temperature reduction kettles, and the purpose of prolonging the service life of the reaction kettle is also achieved.
The method and the system for extracting 4,4' -diaminodiphenyl ether from the DMAC medium have the advantages of simple process, convenient operation, high productivity, low energy consumption, low cost, no introduction of other organic solvents in the extraction process, low pollution and suitability for large-scale industrial application.
The method has no high-temperature heating concentration process, avoids the high-temperature oxidative decomposition of materials, and in the traditional process, if the materials are not heated and concentrated, the materials (about 15 percent) contained in the centrifugate are not crystallized at normal temperature and cannot be separated.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate embodiments of the disclosure and, together with the description, serve to explain the disclosure and not to limit the disclosure.
FIG. 1 is a diagram of a production system for extracting 4,4' -diaminodiphenyl ether from DMAC media in example 2 of the present disclosure.
FIG. 2 is a diagram of a production system for extracting 4,4' -diaminodiphenyl ether from DMAC media in accordance with example 3 of the present disclosure.
FIG. 3 is a flow chart of a process for extracting 4,4' -diaminodiphenyl ether from DMAC media according to the present disclosure.
The device comprises a reaction solvent DMAC (dimethyl acetamide), a raw material 4,4' -dinitrodiphenyl ether feeding tank, a hydrogenation catalyst feeding tank, a material melting tank, a hydrogenation kettle, a thermal filtering device, a primary cooling kettle, a secondary cooling kettle, a vacuum buffer tank, a vacuum pump, a condenser, a condensate storage tank, a heat exchange device and a heat.
Detailed Description
It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of the stated features, steps, operations, and/or combinations thereof, unless the context clearly indicates otherwise.
As introduced in the background art, in the production process of 4,4 '-diaminodiphenyl ether in the traditional process, the centrifuged mother liquor still contains about 15 percent of 4,4' -diaminodiphenyl ether after hydrogenation is finished, and the primary yield is less than 85 percent; when the temperature reaches 130-. In order to solve the above technical problems, in a first exemplary embodiment of the present disclosure, there is provided a method for extracting 4,4' -diaminodiphenyl ether from DMAC medium, the method comprising the steps of:
carrying out hot filtration on hydrogenated liquid containing a solvent DMAC, 4' -diaminodiphenyl ether and a hydrogenation catalyst to remove solids; then, carrying out primary cooling on the hydrogenated liquid, carrying out secondary cooling after the primary cooling, and finally separating to obtain 4,4' -diaminodiphenyl ether;
wherein, the primary cooling adopts water as a cooling medium and is reduced to 38-45 ℃;
the secondary cooling adopts alcohols as cooling medium, and the temperature is reduced from 38-45 ℃ to 10 ℃ or below.
In one or some embodiments of the present disclosure, the hydrogenation solution containing the solvent DMAC, 4' -diaminodiphenyl ether, and the hydrogenation catalyst is prepared by a hydrogenation reaction;
the hydrogenation reaction refers to a reaction process of interaction between hydrogen and 4,4' -dinitrodiphenyl ether. DMAC is taken as a solvent, 4' -dinitrodiphenyl ether is taken as a raw material, and the DMAC is subjected to a reaction catalyzed by a hydrogenation catalyst.
In one or more embodiments of the present disclosure, the temperature of the hydrogenation liquid containing the solvent DMAC, 4' -diaminodiphenyl ether, and the hydrogenation catalyst is maintained at the hydrogenation reaction temperature.
In one or some embodiments of the disclosure, the solid in the hydrogenation reaction is separated by thermal filtration, so that the separation efficiency is high, and the primary yield of the subsequent target product is improved; furthermore, the solid comprises a hydrogenation catalyst and some solid impurities, and the hydrogenation catalyst is separated and then recovered for recycling.
In one or some embodiments of the present disclosure, the primary temperature reduction uses water as a temperature reduction medium, and the temperature is reduced from the reaction temperature to 38-45 ℃. The temperature of the water is 4-30 ℃; further, the temperature of the water is 28 ℃.
In one or some embodiments of the disclosure, the secondary cooling uses alcohol as a cooling medium, and the temperature of the alcohol is-2 to-12 ℃; further, the alcohol is at-10 ℃; further, the alcohol includes, but is not limited to, ethylene glycol. The method preferably adopts glycol or glycol solution, is more suitable for the subsequent cooling of the hydrogenated liquid, and has the advantages of good cooling effect, energy conservation and the like.
In industrial application, less time is consumed for cooling the hydrogenated liquid by using DMAC as a solvent to reach the required temperature of 38-45 ℃, the temperature difference is small, crystallization is uniform, cooling below 45 ℃ consumes too much time, and the load of a subsequent refrigerator higher than 45 ℃ is increased, so that energy consumption is high. In conclusion, the present disclosure reduces the temperature of the hydrogenation solution with DMAC as the solvent to 38-45 ℃ once. According to the method, the hydrogenation liquid at 38-45 ℃ is continuously cooled for the second time to 10 ℃ or below, so that the yield of the primary product can be improved to 98%, and tests prove that if the hydrogenation liquid is cooled to more than 10 ℃, the yield of the primary product cannot be ensured. In conclusion, the temperature of the hydrogenation solution of 38-45 ℃ is secondarily reduced to 10 ℃ or below.
The present disclosure adopts a twice cooling method to cool the hydrogenated liquid using DMAC as a solvent, and has the following advantages in industrial applications: (1) the primary cooling kettle adopts a reaction kettle jacket to introduce circulating water for cooling, the temperature of the hydrogenated liquid is reduced to 38-45 ℃ from the reaction temperature, the cost of cooling the circulating water is low, the temperature difference is small, and the crystallization is uniform. And (3) further physically cooling the secondary cooling kettle, wherein the temperature of the hydrogenation solution is reduced to 10 ℃ or below from 38-45 ℃. (2) If the temperature of the material is directly reduced to 10 ℃ or below by adopting the cooling kettle, the refrigeration cost is high, and the material is hung on the wall when the temperature difference is too large. (3) Through twice cooling, the obtained product has uniform crystallization, high product quality and good appearance effect.
In a second exemplary embodiment of the present disclosure, a method for preparing 4,4 '-diaminodiphenyl ether is provided, which includes the method for extracting 4,4' -diaminodiphenyl ether from DMAC medium in any of the above embodiments.
The preparation method comprises the following steps:
(1) DMAC is used as a reaction solvent, 4 '-dinitrodiphenyl ether is used as a raw material, and a hydrogenation liquid containing the DMAC, the 4,4' -diaminodiphenyl ether and a hydrogenation catalyst is prepared through a catalytic reaction of the hydrogenation catalyst;
(2) after the hydrogenation is finished, carrying out hot filtration on hydrogenated liquid containing solvent DMAC, 4' -diaminodiphenyl ether and hydrogenation catalyst to remove solids; then, carrying out primary cooling on the hydrogenated liquid, carrying out secondary cooling after the primary cooling, and finally separating to obtain 4,4' -diaminodiphenyl ether;
wherein, the primary cooling adopts water as a cooling medium and is reduced to 38-45 ℃;
the secondary cooling adopts alcohol as a cooling medium, and the temperature is reduced from 38-45 ℃ to 10 ℃ or below.
In one or more embodiments of the present disclosure, in the step (1), the reaction temperature is 100-.
In one or some embodiments of the present disclosure, in the step (1), the hydrogen gas supply pressure is 0.75MPa, the hydrogenation kettle pressure is 0.1-0.6MPa or 650 Nm 800 Nm/kettle3。
In one or some embodiments of the disclosure, in step (1), the feeding mass ratio of the solvent DMAC to 4,4' -dinitrodiphenyl ether in the hydrogenation reaction is 1-2: 1;
furthermore, the feeding mass ratio of the solvent DMAC to the 4,4' -dinitrodiphenyl ether is 23: 15.
In one or some embodiments of the present disclosure, in step (1), the hydrogenation catalyst includes, but is not limited to, palladium on carbon catalyst, and is used in an amount of 0.03 to 0.06% by mass of 4,4' -dinitrodiphenyl ether.
In one or some embodiments of the disclosure, for the completion of the hydrogenation reaction, the temperature is maintained for 1.5 to 2.5 hours after the hydrogenation reaction is completed; further, the heat preservation time is 2 hours.
In a third exemplary embodiment of the present disclosure, there is provided a system for extracting 4,4' -diaminodiphenyl ether from DMAC media, comprising:
the hydrogenation kettle, the thermal filtering equipment, the primary cooling kettle and the secondary cooling kettle are sequentially communicated;
the primary cooling kettle comprises a first jacket, and the first jacket is provided with a water inlet and outlet pipeline;
the secondary cooling kettle comprises a second jacket, and the second jacket is provided with an alcohol inlet and outlet pipeline.
In this one or some embodiments of the disclosure, adopt once cooling cauldron and secondary cooling cauldron to cool down, adopt the circulating water as the cooling medium during once cooling, what adopt during the secondary cooling is that the ethylene glycol does the cooling medium, in industry practical application, use two cauldron cooling mainly to avoid circulating water and ethylene glycol to intermix, otherwise can reduce refrigeration effect and production efficiency.
In one or some embodiments of the disclosure, the thermal filtering device is a precision filter, which separates out the hydrogenation catalyst with high separation efficiency.
In one or some embodiments of the present disclosure, the system further comprises a refrigerator for refrigerating the refrigerant medium entering the alcohol inlet line.
In a fourth exemplary embodiment of the present disclosure, a system for producing 4,4 '-diaminodiphenyl ether is provided, the system including one of the above-described embodiments for extracting 4,4' -diaminodiphenyl ether from DMAC media.
In one or some embodiments of the disclosure, the system further comprises: at least 1 material dissolving kettle communicated with the hydrogenation kettle can be used for containing a mixture of the solvent and the raw material 4,4 '-dinitrodiphenyl ether or a mixture of the solvent, the raw material 4,4' -dinitrodiphenyl ether and the hydrogenation catalyst.
Further, the system further comprises: 3 feeding tanks communicated with the material dissolving kettle are respectively used for containing a solvent, the raw material 4,4' -dinitrodiphenyl ether or a hydrogenation catalyst; or 2 feeding tanks communicated with the material dissolving kettle are respectively used for containing the solvent or the raw material 4,4' -dinitrodiphenyl ether, and 1 feeding tank communicated with the hydrogenation kettle is used for containing the hydrogenation catalyst.
In one or some embodiments of the present disclosure, the system further includes a vacuum material storage device, which includes a vacuum pump, a vacuum buffer tank, a condenser, a condensate storage tank, etc., the hydrogenation kettle, the condenser, the condensate storage tank, the vacuum buffer tank, and the vacuum pump are sequentially connected, the vacuum pump vacuumizes the hydrogenation kettle, the vacuum buffer tank prevents the liquid from being pumped into the vacuum pump, the condenser is used to cool the volatile DMAC extracted by vacuum, and the condensate storage tank is used to recover and store the condensed liquid DMAC.
Furthermore, 2 vacuum pumps can be used (one for one), 2 vacuum buffer tanks can be used, 2 condensers can be used, and the vacuum pipeline system is connected with each reaction kettle. Opening a vacuum valve of a hydrogenation kettle for vacuumizing, opening a bottom valve of a material melting kettle and an emptying valve when observing the vacuum degree of a pressure gauge to be-0.08 MPa, pumping the material into the hydrogenation kettle through a pipeline (pumping the mixed catalyst into the hydrogenation kettle through a catalyst feed port when transferring the material, constantly observing the material allowance in the middle kettle and the air inflow of the emptying valve, indicating that the material is completely transferred when the air inflow of the emptying valve is large, observing the middle kettle, closing the bottom valve of the middle kettle after confirming that the material is transferred to be empty, closing all valves on the hydrogenation kettle, opening the vacuum and pumping to-0.08 MPa.
In one or some embodiments of the present disclosure, the system further comprises a solid-liquid separation device, which may be connected to the secondary reduced temperature kettle, the solid-liquid separation device including, but not limited to, a centrifuge.
In order to make the technical solutions of the present disclosure more clearly understood by those skilled in the art, the technical solutions of the present disclosure will be described in detail below with reference to specific embodiments.
Example 1
A system for extracting 4,4' -diaminodiphenyl ether from DMAC media comprising:
the hydrogenation kettle, the thermal filtering equipment, the primary cooling kettle and the secondary cooling kettle are sequentially communicated; the primary cooling kettle comprises a first jacket, and a water inlet pipeline is arranged in the first jacket;
the secondary cooling kettle comprises a second jacket, and an alcohol inlet pipeline is arranged in the second jacket;
and 1 refrigerating machine for refrigerating the refrigerating medium in the alcohol inlet pipeline.
Example 2
A production system of 4,4' -diaminodiphenyl ether is shown in figure 1 and comprises:
the device comprises a material melting kettle 4, a hydrogenation kettle 5, a thermal filtering device 6, a primary cooling kettle 7 and a secondary cooling kettle 8 which are communicated in sequence, wherein the primary cooling kettle 6 is provided with a first jacket, and a water inlet pipeline is arranged in the first jacket; the secondary cooling kettle 7 is provided with a second jacket, and an alcohol inlet pipeline is arranged in the second jacket;
further comprising: 2 feeding tanks communicated with the material dissolving kettle 4 are respectively a feeding tank 1 containing a reaction solvent DMAC and a feeding tank 2 containing raw material 4,4' -dinitrodiphenyl ether;
further comprising: 1 feeding tank 3 which is communicated with the hydrogenation kettle 5 and is filled with hydrogenation catalyst;
further comprising: 1 centrifugal machine connected with the secondary cooling kettle 8;
and 1 refrigerating machine for refrigerating the refrigerating medium in the alcohol inlet pipeline.
Example 3
A production system of 4,4' -diaminodiphenyl ether, as shown in fig. 2, comprising:
the device comprises a material melting kettle 4, a hydrogenation kettle 5, a thermal filtering device 6, a primary cooling kettle 7 and a secondary cooling kettle 8 which are communicated in sequence, wherein the primary cooling kettle 6 is provided with a first jacket, and a water inlet pipeline is arranged in the first jacket; the secondary cooling kettle 7 is provided with a second jacket, and an alcohol inlet pipeline is arranged in the second jacket;
further comprising: 2 feeding tanks connected with the material dissolving kettle 4 are respectively a feeding tank 1 containing a reaction solvent DMAC and a feeding tank 2 containing raw material 4,4' -dinitrodiphenyl ether;
further comprising: 1 feeding tank 3 which is communicated with the hydrogenation kettle 5 and is filled with hydrogenation catalyst;
further comprising: 1 centrifugal machine connected with the secondary cooling kettle;
further comprising: real empty material equipment specifically includes: the system comprises a vacuum pump 9, a vacuum buffer tank 10, a condenser 11 and a condensation storage tank 12, wherein the hydrogenation kettle, the condenser, a condensate storage tank, the vacuum buffer tank and the vacuum pump are sequentially connected;
and 1 refrigerating machine for refrigerating the refrigerating medium in the alcohol inlet pipeline.
Example 4
A method of extracting 4,4' -diaminodiphenyl ether from DMAC media, using the system of example 1, comprising the steps of:
(1) carrying out heat preservation on 2700L-3000L of hydrogenation liquid containing DMAC (dimethylacetamide) solvent, 4' -diaminodiphenyl ether and hydrogenation catalyst after the hydrogenation reaction is finished for 2h, and carrying out heat filtration after the heat preservation to remove the hydrogenation catalyst;
(2) the temperature of the primary cooling kettle jacket is lowered to about 40 ℃ by feeding water, the temperature of circulating water is about 28 ℃, and the time for lowering the hydrogenation reaction temperature to 40 ℃ is about 1.5 h;
(3) transferring the material from the primary cooling kettle to a secondary cooling kettle for further cooling;
(4) cooling the jacket of the secondary cooling kettle by using a glycol refrigerant at the temperature of-10 ℃, wherein the time for cooling from 40 ℃ to 10 ℃ is 0.5h, and when the temperature of the kettle is reduced to below 10 ℃, centrifuging to obtain the crude 4,4' -diaminodiphenyl ether.
The yield of the 4,4' -diaminodiphenyl ether crude product in one time is 99.6%, and the obtained product has uniform crystallization, high product quality and good appearance effect.
Wherein the product yield (%) is equal to the mass of 4,4' -diaminodiphenyl ether in the crude 4,4' -diaminodiphenyl ether/the mass of 4,4' -diaminodiphenyl ether in the hydrogenation solution in step (1) × 100%.
Example 5
The preparation method of 4,4' -diaminodiphenyl ether can adopt the system in the embodiment 1, 2 or 3, and the flow chart is shown in figure 3, and comprises the following steps:
(1) adding 2300 kg of DMAC (dimethyl acetamide), 1500 kg of 4,4' -dinitrodiphenyl ether and 0.5 kg of palladium carbon catalyst into a material dissolving kettle, heating to 85 ℃, keeping the temperature for 30 minutes, and transferring the materials to a hydrogenation kettle in vacuum.
(2) The hydrogenation kettle is stirred and replaced by nitrogen for three times.
(3) After the replacement is finished, the hydrogenation reaction temperature is 108-110 ℃, the hydrogen gas supply pressure is 0.75MPa, the hydrogenation kettle pressure is 0.3MPa, and the dosage in each kettle is 700Nm3Left and right.
After about 2-3 hours of hydrogenation, obtaining hydrogenated liquid.
(4) After preserving the heat for 2 hours, hot filtering the mixture into a primary cooling kettle.
(5) The temperature of the primary cooling kettle jacket is lowered to about 40 ℃ by feeding water, the temperature of circulating water is about 28 ℃, and the time for lowering the hydrogenation reaction temperature to 40 ℃ is about 1.5 h.
(6) The material is shifted from the primary cooling kettle to the secondary cooling kettle to be continuously cooled.
(7) Cooling the jacket of the secondary cooling kettle by using a glycol refrigerant at the temperature of-10 ℃, wherein the time for cooling from 40 ℃ to 10 ℃ is 0.5h, and when the temperature of the kettle is reduced to 10 ℃, centrifuging to obtain the crude 4,4' -diaminodiphenyl ether.
The yield of the 4,4' -diaminodiphenyl ether crude product in one time is 99.6%, and the obtained product has uniform crystallization, high product quality and good appearance effect.
Example 6
The preparation process of 4,4' -diamino diphenyl ether may be adopted in the system of example 1, 2 or 3 and includes the following steps:
(1) adding 2500 kg of DMAC (dimethyl acetamide), 1700 kg of 4,4' -dinitrodiphenyl ether and 1 kg of palladium carbon catalyst into a material dissolving kettle, heating to 85 ℃, preserving heat for 30 minutes, and transferring materials to a hydrogenation kettle in vacuum.
(2) The hydrogenation kettle is stirred and replaced by nitrogen for three times.
(3) After the replacement is finished, the hydrogenation reaction temperature is 110-115 ℃, the hydrogenation pressure is 0.55MPa, and the usage amount of hydrogen is 795Nm3And after about 2 to 3 hours of hydrogenation, obtaining hydrogenated liquid.
(4) After preserving the heat for 2 hours, hot filtering the mixture into a primary cooling kettle.
(5) The temperature of the inlet water of the primary cooling kettle jacket is reduced to about 38 ℃, the temperature of the circulating water is about 28 ℃, and the time for reducing the hydrogenation reaction temperature to 38 ℃ is about 2 hours.
(6) The material is shifted from the primary cooling kettle to the secondary cooling kettle to be continuously cooled.
(7) Cooling the jacket of the secondary cooling kettle by using a glycol refrigerant at the temperature of-12 ℃, wherein the time for cooling from 38 ℃ to 10 ℃ is 0.5h, and when the temperature of the kettle is reduced to 10 ℃, centrifuging to obtain the crude 4,4' -diaminodiphenyl ether.
The yield of the 4,4' -diaminodiphenyl ether crude product in one time is 99.3%, and the obtained product has uniform crystallization, high product quality and good appearance effect.
Example 7
The preparation process of 4,4' -diamino diphenyl ether may be adopted in the system of example 1, 2 or 3 and includes the following steps:
(1) 2400 kg of DMAC solvent, 1600 kg of 4,4' -dinitrodiphenyl ether and 0.6 kg of palladium carbon catalyst are added into a material dissolving kettle, the temperature is raised to 88 ℃, the temperature is kept for 30 minutes, and the materials are transferred to a hydrogenation kettle in vacuum.
(2) The hydrogenation kettle is stirred and replaced by nitrogen for three times.
(3) After the replacement is finished, the hydrogenation reaction temperature is 108-112 ℃, and the usage amount of hydrogen is 750Nm3Or the hydrogenation pressure is 00.5MPa, and the hydrogenation is finished within about 2-3 hours to obtain hydrogenation liquid.
(4) After preserving the heat for 2 hours, hot filtering the mixture into a primary cooling kettle.
(5) The temperature of the inlet water of the primary cooling kettle jacket is reduced to about 42 ℃, the temperature of the circulating water is about 28 ℃, and the time for reducing the hydrogenation reaction temperature to 42 ℃ is about 0.8 h.
(6) The material is shifted from the primary cooling kettle to the secondary cooling kettle to be continuously cooled.
(7) Cooling the jacket of the secondary cooling kettle by using a glycol refrigerant at the temperature of-8 ℃, wherein the time for cooling from 42 ℃ to 10 ℃ is 0.5h, and when the temperature of the kettle is reduced to 8 ℃, centrifuging to obtain the crude 4,4' -diaminodiphenyl ether.
The yield of the 4,4' -diaminodiphenyl ether crude product in one time is 99.4%, and the obtained product has uniform crystallization, high product quality and good appearance effect.
Comparative example 1
As in example 3, the points of difference are:the test is a small-scale production test,DMAC is replaced by other amide solvents (such as DMF and NMP) or other organic solvents, and experiments prove that the obtained product has low primary yield, uneven product crystallinity and the like.
Comparative example 2
A preparation method of 4,4' -diaminodiphenyl ether comprises the following steps:
(1) adding 23 kg of solvent DMAC, 15 kg of 4,4' -dinitrodiphenyl ether and 0.005 kg of palladium carbon catalyst into a material dissolving kettle, heating to 85 ℃, preserving heat for 30 minutes, and transferring materials to a hydrogenation kettle in vacuum.
(2) The hydrogenation kettle is stirred and replaced by nitrogen for three times.
(3) After the replacement is finished, the hydrogenation is carried out at the temperature of 108-.
(4) After preserving the heat for 2 hours, hot filtering the mixture into a primary cooling kettle.
(5) The cooling kettle is jacketed with glycol to be cooled to about 10 ℃, and the temperature of the glycol is about-10 ℃.
When the temperature of the kettle is reduced to 10 ℃, centrifuging to obtain the crude product of the 4,4' -diaminodiphenyl ether.
The obtained product has the advantages of low one-time yield, uneven product crystallinity, serious wall hanging phenomenon of materials, high energy consumption and high cost.
The above embodiments are preferred embodiments of the present disclosure, but the embodiments of the present disclosure are not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present disclosure should be regarded as equivalent replacements within the scope of the present disclosure.
Claims (10)
1. A process for the extraction of 4,4' -diaminodiphenyl ether from DMAC media, characterized in that it comprises the following steps:
carrying out hot filtration on hydrogenated liquid containing a solvent DMAC, 4' -diaminodiphenyl ether and a hydrogenation catalyst to remove solids; then, carrying out primary cooling on the hydrogenated liquid, carrying out secondary cooling after the primary cooling, and finally separating to obtain 4,4' -diaminodiphenyl ether;
wherein, the primary cooling adopts water as a cooling medium and is reduced to 38-45 ℃;
the secondary cooling adopts alcohols as cooling medium, and the temperature is reduced from 38-45 ℃ to 10 ℃ or below.
2. The process of claim 1, wherein the hydrogenation solution comprising DMAC as solvent, 4' -diaminodiphenyl ether and a hydrogenation catalyst is prepared by hydrogenation.
3. The process of claim 1, wherein the hydrogenation solution comprising the solvent DMAC, 4' -diaminodiphenyl ether and the hydrogenation catalyst is maintained at the hydrogenation reaction temperature.
4. The method of claim 1, wherein the water is at a temperature of 4-30 ℃; further, the temperature of the water is 28 ℃.
5. The method of claim 1, wherein the alcohol is ethylene glycol;
further, the temperature of the alcohol substance is-2 to-12 ℃; further, the temperature of the alcohol is-10 ℃.
6. A method for producing 4,4 '-diaminodiphenyl ether, which is characterized by extracting 4,4' -diaminodiphenyl ether from DMAC medium according to any one of claims 1 to 5.
7. The method of claim 6, comprising the steps of:
(1) DMAC is used as a reaction solvent, 4 '-dinitrodiphenyl ether is used as a raw material, and a hydrogenation liquid containing the DMAC, the 4,4' -diaminodiphenyl ether and a hydrogenation catalyst is prepared through a catalytic reaction of the hydrogenation catalyst;
(2) after the hydrogenation is finished, carrying out hot filtration on hydrogenated liquid containing solvent DMAC, 4' -diaminodiphenyl ether and hydrogenation catalyst to remove solids; then, carrying out primary cooling on the hydrogenated liquid, carrying out secondary cooling after the primary cooling, and finally separating to obtain 4,4' -diaminodiphenyl ether;
wherein, the primary cooling adopts water as a cooling medium and is reduced to 38-45 ℃;
the secondary cooling adopts alcohol as a cooling medium, and the temperature is reduced from 38-45 ℃ to 10 ℃ or below;
further, in the step (1), the hydrogenation catalyst comprises a palladium-carbon catalyst, and the using amount of the palladium-carbon catalyst is 0.03-0.06% of the mass of the 4,4' -dinitrodiphenyl ether;
further, in the step (1), the reaction temperature of the hydrogenation reaction is 100-;
further, in the step (1), in the hydrogenation reaction, the feeding mass ratio of the solvent DMAC to the 4,4' -dinitrodiphenyl ether is 1-2: 1; furthermore, the feeding mass ratio of the solvent DMAC to the 4,4' -dinitrodiphenyl ether is 23: 15;
further, in the step (1), in the hydrogenation reaction, the hydrogenation time is 2-3h, and the pressure of a hydrogenation kettle is 0.1-0.6 MPa;
further, in the step (2), heat preservation is carried out after the hydrogenation is finished, and the heat preservation time is 1.5-2.5 h; furthermore, the heat preservation time is 2 hours.
8. A system for extracting 4,4' -diaminodiphenyl ether from DMAC media, comprising:
the hydrogenation kettle, the thermal filtering equipment, the primary cooling kettle and the secondary cooling kettle are sequentially communicated;
the primary cooling kettle comprises a first jacket, and a water inlet pipeline is arranged in the first jacket;
the secondary cooling kettle comprises a second jacket, and an alcohol inlet pipeline is arranged in the second jacket;
further, the hot filtering device is a precision filter;
furthermore, the system also comprises a refrigerating machine for refrigerating the refrigerating medium in the alcohol inlet pipeline.
9. A system for producing 4,4 '-diaminodiphenyl ether, characterized in that it comprises a DMAC medium extraction system of 4,4' -diaminodiphenyl ether according to claim 8.
10. The system of claim 9, wherein the system further comprises: at least 1 material dissolving kettle communicated with the hydrogenation kettle;
further, the system also comprises vacuum material storage equipment, wherein the vacuum material storage equipment comprises a vacuum pump, a vacuum buffer tank, a condenser and a condensate storage tank, and the hydrogenation kettle, the condenser, the condensate storage tank, the vacuum buffer tank and the vacuum pump are sequentially connected.
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