CN110885305A - NMP side draw method - Google Patents
NMP side draw method Download PDFInfo
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- CN110885305A CN110885305A CN201910910432.9A CN201910910432A CN110885305A CN 110885305 A CN110885305 A CN 110885305A CN 201910910432 A CN201910910432 A CN 201910910432A CN 110885305 A CN110885305 A CN 110885305A
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- CN
- China
- Prior art keywords
- rectifying tower
- nmp
- reflux
- raw materials
- pipeline
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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- 238000000034 method Methods 0.000 title claims abstract description 24
- 239000002994 raw material Substances 0.000 claims abstract description 32
- 238000010992 reflux Methods 0.000 claims abstract description 29
- 238000000605 extraction Methods 0.000 claims abstract description 19
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 16
- 230000003472 neutralizing effect Effects 0.000 claims abstract description 12
- 239000012535 impurity Substances 0.000 claims abstract description 7
- 238000004821 distillation Methods 0.000 claims description 3
- HCSCWJCZRCSQFA-UHFFFAOYSA-N 1-methylpyrrolidin-2-one;hydrate Chemical compound O.CN1CCCC1=O HCSCWJCZRCSQFA-UHFFFAOYSA-N 0.000 abstract description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 3
- 239000000284 extract Substances 0.000 abstract 1
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 description 53
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 3
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 3
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 3
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 description 3
- 238000011084 recovery Methods 0.000 description 3
- HEDRZPFGACZZDS-UHFFFAOYSA-N Chloroform Chemical compound ClC(Cl)Cl HEDRZPFGACZZDS-UHFFFAOYSA-N 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 1
- 150000001412 amines Chemical class 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 239000012459 cleaning agent Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 150000002484 inorganic compounds Chemical class 0.000 description 1
- 229910010272 inorganic material Inorganic materials 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 229910052744 lithium Inorganic materials 0.000 description 1
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 239000000575 pesticide Substances 0.000 description 1
- 239000000049 pigment Substances 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D207/00—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom
- C07D207/02—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom
- C07D207/18—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having one double bond between ring members or between a ring member and a non-ring member
- C07D207/22—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having one double bond between ring members or between a ring member and a non-ring member with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D207/24—Oxygen or sulfur atoms
- C07D207/26—2-Pyrrolidones
- C07D207/263—2-Pyrrolidones with only hydrogen atoms or radicals containing only hydrogen and carbon atoms directly attached to other ring carbon atoms
- C07D207/267—2-Pyrrolidones with only hydrogen atoms or radicals containing only hydrogen and carbon atoms directly attached to other ring carbon atoms with only hydrogen atoms or radicals containing only hydrogen and carbon atoms directly attached to the ring nitrogen atom
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)
- Extraction Or Liquid Replacement (AREA)
Abstract
An NMP side draw method comprises the following steps: neutralizing, namely neutralizing the raw materials, and adjusting the pH value of the raw materials to 9; separating in a first rectifying tower, introducing the neutralized raw material into the first rectifying tower, and separating moisture, light components and impurities azeotropic with water in the first rectifying tower; separating by a second rectifying tower, introducing the raw material separated by the first rectifying tower into the second rectifying tower, wherein one side of the second rectifying tower is provided with a extraction pipeline, and one side of the extraction pipeline is connected with a condenser; a reflux pipeline is arranged at the top of the second rectifying tower; the raw materials are separated by a second rectifying tower, are totally refluxed by a top reflux pipeline, and are discontinuously extracted by an extraction pipeline and a condenser on one side; and obtaining an NMP product at the top of the second rectifying tower. The invention intermittently extracts a small amount of water, the production control is stable, the product quality can reach more than 99.8 percent of NMP content, and the recovered NMP water content is reduced to be less than 100 ppm.
Description
Technical Field
The invention belongs to the technical field of organic solvent recovery treatment, and particularly relates to an NMP side draw method.
Background
N-methylpyrrolidone, a chinese alias: NMP; 1-methyl-2-pyrrolidone; n-methyl-2-pyrrolidone. Colorless transparent oily liquid, slightly having amine odor. Low volatility, good thermal stability and chemical stability, and can be volatilized with water vapor. It has hygroscopic property. Is sensitive to light. It is easily soluble in water, ethanol, diethyl ether, acetone, ethyl acetate, chloroform and benzene, and can dissolve most organic and inorganic compounds, polar gas, natural and synthetic high molecular compounds. N-methyl pyrrolidone is widely applied to the industries of lithium batteries, medicines, pesticides, pigments, cleaning agents, insulating materials and the like.
In the prior art, usually, a rectification separation and technical method is adopted for recycling NMP, a raw material is neutralized firstly, so that the pH value is controlled to be about 9 weak alkaline, water, light components and impurities azeotropic with water are separated at the tower top of a rectification tower 1, non-volatile components and high-boiling point heavy components are separated at a tower bottom of a tower 2, and an NMP product is obtained at the tower top of the tower 2.
However, in the actual operation process, bubbles are generated in the tower after the raw materials are neutralized, so that the control of the components at the top of the tower is unstable, the quality of the product is affected, and high-quality products with the content of more than 99.8 percent and the moisture of less than 200ppm cannot be obtained.
Disclosure of Invention
Aiming at the problems, the invention discloses an NMP side draw method.
The specific technical scheme is as follows:
an NMP side draw method is characterized by comprising the following steps:
step (1): neutralizing, namely neutralizing the raw materials, and adjusting the pH value of the raw materials to 9;
step (2): separating in a first rectifying tower, introducing the neutralized raw material into the first rectifying tower, and separating moisture, light components and impurities azeotropic with water in the first rectifying tower;
and (3): separating by a second rectifying tower, introducing the raw material separated by the first rectifying tower into the second rectifying tower, wherein one side of the second rectifying tower is provided with a extraction pipeline, and one side of the extraction pipeline is connected with a condenser; a reflux pipeline is arranged at the top of the second rectifying tower; the raw materials are separated by a second rectifying tower, are totally refluxed by a top reflux pipeline, and are discontinuously extracted by an extraction pipeline and a condenser on one side; and obtaining an NMP product at the top of the second rectifying tower.
Further, the set pressure of the first rectifying tower is 10Kpa, the TOP temperature is 53 ℃, the BTM temperature is 130 ℃, the reflux ratio is 5.0, the reflux amount is not less than 1026.5kg/h, the Feed flow is 651.2kg/h, the BTM removal flow is 445.9kg/h, and the steam temperature is 155 ℃.
Further, the set pressure of the second rectifying tower is 6.7Kpa, the TOP temperature is 117 ℃, the BTM temperature is 130 ℃, the reflux quantity is not less than 976kg/h, the side stream flow rate is 438kg/h, the Feed flow rate is 445.9kg/h, the BTM extraction flow rate is 8kg/h, and the steam temperature is 155 ℃.
The invention has the beneficial effects that:
a side-draw process is specially designed on the second rectifying tower, and a return pipeline at the top of the second rectifying tower is matched to form total reflux, so that a small amount of water is intermittently drawn, the stable production control can be ensured, the product quality can reach more than 99.8 percent of NMP content, and the recovered NMP water content is reduced to less than 100 ppm. The method has the advantages of simple process steps, good use effect, good product yield and high quality, and can greatly improve the recovery efficiency of the NMP and improve the quality of the recovered product.
Detailed Description
In order to make the technical solution of the present invention clearer and more clear, the present invention is further described below, and any solution obtained by substituting technical features of the technical solution of the present invention with equivalents and performing conventional reasoning falls within the scope of the present invention.
In this embodiment, the parameters of the evaporator used in the rectifying tower are as follows: the set pressure was 10Kpa, the TOP temperature was 120 ℃, the BTM temperature was 130 ℃, the Feed flow was 723.5kg/h, and the BTM removal flow was 72.4 kg/h.
Example 1
An NMP side draw method is characterized by comprising the following steps:
step (1): neutralizing, namely neutralizing the raw materials, and adjusting the pH value of the raw materials to 9;
step (2): separating in a first rectifying tower, introducing the neutralized raw material into the first rectifying tower, and separating moisture, light components and impurities azeotropic with water in the first rectifying tower;
and (3): separating by a second rectifying tower, introducing the raw material separated by the first rectifying tower into the second rectifying tower, wherein one side of the second rectifying tower is provided with a extraction pipeline, and one side of the extraction pipeline is connected with a condenser; a reflux pipeline is arranged at the top of the second rectifying tower; the raw materials are separated by a second rectifying tower, are totally refluxed by a top reflux pipeline, and are discontinuously extracted by an extraction pipeline and a condenser on one side; and obtaining an NMP product at the top of the second rectifying tower.
Further, the set pressure of the first distillation column was 10Kpa, the TOP temperature was 53 ℃, the BTM temperature was 130 ℃, the reflux ratio was 5.0, the reflux amount was 1026.5kg/h, the Feed flow was 651.2kg/h, the BTM removal flow was 445.9kg/h, and the steam temperature was 155 ℃.
Further, the set pressure of the second rectifying tower was 6.7Kpa, the TOP temperature was 117 ℃, the BTM temperature was 130 ℃, the reflux rate was 976kg/h, the sidestream flow was 438kg/h, the Feed flow was 445.9kg/h, the BTM withdrawal flow was 8kg/h, and the steam temperature was 155 ℃.
In the embodiment, the quality of the obtained product can reach more than 99.8 percent of NMP content, and the water content of the recovered NMP is reduced to 100 ppm.
Example 2
An NMP side draw method is characterized by comprising the following steps:
step (1): neutralizing, namely neutralizing the raw materials, and adjusting the pH value of the raw materials to 9;
step (2): separating in a first rectifying tower, introducing the neutralized raw material into the first rectifying tower, and separating moisture, light components and impurities azeotropic with water in the first rectifying tower;
and (3): separating by a second rectifying tower, introducing the raw material separated by the first rectifying tower into the second rectifying tower, wherein one side of the second rectifying tower is provided with a extraction pipeline, and one side of the extraction pipeline is connected with a condenser; a reflux pipeline is arranged at the top of the second rectifying tower; the raw materials are separated by a second rectifying tower, are totally refluxed by a top reflux pipeline, and are discontinuously extracted by an extraction pipeline and a condenser on one side; and obtaining an NMP product at the top of the second rectifying tower.
Further, the set pressure of the first rectifying tower was 10Kpa, the TOP temperature was 53 ℃, the BTM temperature was 130 ℃, the reflux ratio was 5.0, the reflux amount was 1125kg/h, the Feed flow was 651.2kg/h, the BTM removal flow was 445.9kg/h, and the steam temperature was 155 ℃.
Further, the set pressure of the second rectifying tower is 6.7Kpa, the TOP temperature is 117 ℃, the BTM temperature is 130 ℃, the reflux quantity is 990kg/h, the side stream flow is 438kg/h, the Feed flow is 445.9kg/h, the BTM withdrawal flow is 8kg/h, and the steam temperature is 155 ℃.
In the embodiment, the quality of the obtained product can reach more than 99.85 percent of NMP content, and the water content of the recovered NMP is reduced to 90 ppm.
Example 3
An NMP side draw method is characterized by comprising the following steps:
step (1): neutralizing, namely neutralizing the raw materials, and adjusting the pH value of the raw materials to 9;
step (2): separating in a first rectifying tower, introducing the neutralized raw material into the first rectifying tower, and separating moisture, light components and impurities azeotropic with water in the first rectifying tower;
and (3): separating by a second rectifying tower, introducing the raw material separated by the first rectifying tower into the second rectifying tower, wherein one side of the second rectifying tower is provided with a extraction pipeline, and one side of the extraction pipeline is connected with a condenser; a reflux pipeline is arranged at the top of the second rectifying tower; the raw materials are separated by a second rectifying tower, are totally refluxed by a top reflux pipeline, and are discontinuously extracted by an extraction pipeline and a condenser on one side; and obtaining an NMP product at the top of the second rectifying tower.
Further, the set pressure of the first rectifying tower was 10Kpa, the TOP temperature was 53 ℃, the BTM temperature was 130 ℃, the reflux ratio was 5.0, the reflux amount was 1155.5kg/h, the Feed flow was 651.2kg/h, the BTM removal flow was 445.9kg/h, and the steam temperature was 155 ℃.
Further, the set pressure of the second rectifying tower is 6.7Kpa, the TOP temperature is 117 ℃, the BTM temperature is 130 ℃, the reflux quantity is 1025kg/h, the side stream flow rate is 438kg/h, the Feed flow rate is 445.9kg/h, the BTM withdrawal flow rate is 8kg/h, and the steam temperature is 155 ℃.
In the embodiment, the quality of the obtained product can reach more than 99.9 percent of NMP content, and the water content of the recovered NMP is reduced to 88 ppm.
The invention has the beneficial effects that:
a side-draw process is specially designed on the second rectifying tower, and a return pipeline at the top of the second rectifying tower is matched to form total reflux, so that a small amount of water is intermittently drawn, the stable production control can be ensured, the product quality can reach more than 99.8 of NMP content, and the recovered NMP water content is reduced to less than 100 ppm. The method has the advantages of simple process steps, good use effect, good product yield and high quality, and can greatly improve the recovery efficiency of the NMP and improve the quality of the recovered product.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (7)
1. An NMP side draw method is characterized by comprising the following steps:
step (1): neutralizing, namely neutralizing the raw materials, and adjusting the pH value of the raw materials to 9;
step (2): separating in a first rectifying tower, introducing the neutralized raw material into the first rectifying tower, and separating moisture, light components and impurities azeotropic with water in the first rectifying tower;
and (3): separating by a second rectifying tower, introducing the raw material separated by the first rectifying tower into the second rectifying tower, wherein one side of the second rectifying tower is provided with a extraction pipeline, and one side of the extraction pipeline is connected with a condenser; a reflux pipeline is arranged at the top of the second rectifying tower; the raw materials are separated by a second rectifying tower, are totally refluxed by a top reflux pipeline, and are discontinuously extracted by an extraction pipeline and a condenser on one side; and obtaining an NMP product at the top of the second rectifying tower.
2. The NMP sidedraw method of claim 1, wherein the first distillation column is set at a pressure of 10Kpa, TOP temperature of 53 ℃ and BTM temperature of 130 ℃.
3. The NMP sidedraw process of claim 1, wherein the Feed flow of the first rectification column is 651.2kg/h, the BTM withdrawal flow is 445.9kg/h, and the steam temperature is 155 ℃.
4. The NMP sidedraw method according to claim 1, wherein the reflux ratio of the first rectifying column is 5.0 and the reflux amount is not less than 1026.5 kg/h.
5. The NMP sidedraw process of claim 1, wherein the second distillation column is set at 6.7Kpa, TOP temperature 117 ℃, BTM temperature 130 ℃ and sidedraw flow 438 kg/h.
6. The NMP sidedraw process according to claim 1, wherein the Feed flow of the first rectification column is 445.9kg/h, the BTM withdrawal flow is 8kg/h and the steam temperature is 155 ℃.
7. The NMP sidedraw method according to claim 1, wherein the reflux amount of the second rectifying column is 976kg/h or more.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910910432.9A CN110885305A (en) | 2019-09-25 | 2019-09-25 | NMP side draw method |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910910432.9A CN110885305A (en) | 2019-09-25 | 2019-09-25 | NMP side draw method |
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| Publication Number | Publication Date |
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| CN110885305A true CN110885305A (en) | 2020-03-17 |
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| CN201910910432.9A Pending CN110885305A (en) | 2019-09-25 | 2019-09-25 | NMP side draw method |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113354567A (en) * | 2021-06-24 | 2021-09-07 | 索闻特环保科技(上海)有限公司 | Method for preparing anhydrous NMP by mixed solution of NMP and water |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101508667A (en) * | 2009-03-30 | 2009-08-19 | 濮阳迈奇科技有限公司 | Purification method of N-methyl pyrrolidone |
| JP2012188369A (en) * | 2011-03-09 | 2012-10-04 | Mitsubishi Chemical Engineering Corp | Distillation system for nmp |
| CN206204194U (en) * | 2016-08-31 | 2017-05-31 | 烟台国邦化工机械科技有限公司 | A kind of device that high-purity N methyl pyrrolidone is obtained by the de- amine of rectifying, dehydration |
| CN108658829A (en) * | 2018-07-17 | 2018-10-16 | 天津中福环保科技股份有限公司 | The refined method and apparatus of NMP recycling in a kind of production of lithium battery |
| CN109232352A (en) * | 2018-09-19 | 2019-01-18 | 江阴市大洋固废处置利用有限公司 | N-methyl pyrrolidone decompression purification system and purification method |
| CN209010423U (en) * | 2018-09-19 | 2019-06-21 | 江阴市大洋固废处置利用有限公司 | N-methyl pyrrolidone decompression purification system |
-
2019
- 2019-09-25 CN CN201910910432.9A patent/CN110885305A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101508667A (en) * | 2009-03-30 | 2009-08-19 | 濮阳迈奇科技有限公司 | Purification method of N-methyl pyrrolidone |
| JP2012188369A (en) * | 2011-03-09 | 2012-10-04 | Mitsubishi Chemical Engineering Corp | Distillation system for nmp |
| CN206204194U (en) * | 2016-08-31 | 2017-05-31 | 烟台国邦化工机械科技有限公司 | A kind of device that high-purity N methyl pyrrolidone is obtained by the de- amine of rectifying, dehydration |
| CN108658829A (en) * | 2018-07-17 | 2018-10-16 | 天津中福环保科技股份有限公司 | The refined method and apparatus of NMP recycling in a kind of production of lithium battery |
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| Title |
|---|
| 沈众 等: "锂电池回收液NMP精馏小试研究", 《环境科技》 * |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113354567A (en) * | 2021-06-24 | 2021-09-07 | 索闻特环保科技(上海)有限公司 | Method for preparing anhydrous NMP by mixed solution of NMP and water |
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Application publication date: 20200317 |
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