CN107141210B - Method for improving recovery rate of trifluoroacetone - Google Patents
Method for improving recovery rate of trifluoroacetone Download PDFInfo
- Publication number
- CN107141210B CN107141210B CN201610115486.2A CN201610115486A CN107141210B CN 107141210 B CN107141210 B CN 107141210B CN 201610115486 A CN201610115486 A CN 201610115486A CN 107141210 B CN107141210 B CN 107141210B
- Authority
- CN
- China
- Prior art keywords
- trifluoroacetone
- recovery rate
- kettle
- organic solvent
- tail gas
- Prior art date
- 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.)
- Active
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/78—Separation; Purification; Stabilisation; Use of additives
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/78—Separation; Purification; Stabilisation; Use of additives
- C07C45/81—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation
- C07C45/82—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation by distillation
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Crystallography & Structural Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention provides a method for improving the recovery rate of 1,1,1-trifluoroacetone, which comprises the steps of fully mixing 1,1,1-trifluoroacetone tail gas with an organic solvent, and then carrying out rectification operation to obtain the trifluoroacetone. The method provided by the invention can realize the high-efficiency separation of 1,1,1-trifluoroacetone from ethylene and carbon dioxide in tail gas, and has the characteristics of high recovery rate of 1,1,1-trifluoroacetone, low energy consumption and low equipment investment.
Description
Technical Field
The invention relates to a method for improving the recovery rate of 1,1,1-trifluoroacetone, in particular to a method for improving the recovery rate of 1,1,1-trifluoroacetone in industrial tail gas of 1,1, 1-trifluoroacetone.
Background
1,1,1-trifluoroacetone, the name of English 1,1,1-trifluoroacetone, molecular formula CF3COCH3The boiling point is 21.9 ℃, the melting point is-78 ℃, the liquid is colorless and extremely volatile flammable liquid, has the smell of chloroform, is insoluble in water, and is widely applied to the fields of pesticides, medicines and functional materials.
For the production of 1,1,1-trifluoroacetone, 4, 4-trifluoroacetylacetic acid ethyl ester is generally used as a raw material industrially, decarboxylation reaction is carried out under the catalysis of acid to produce 1,1,1-trifluoroacetone, and trifluoroacetone with the purity of more than or equal to 99.0 percent can be obtained after rectification. In the production process, because a large amount of byproducts of ethylene and carbon dioxide are produced, the extremely volatile trifluoroacetone can be taken out from the reaction system by the carbon dioxide and enters a tail gas system without being condensed in time, so that the reaction yield is reduced, and the tail gas emission does not reach the standard.
The recovery of 1,1,1-trifluoroacetone from 1,1,1-trifluoroacetone tail gas is generally carried out by adopting a secondary condensation method, and the temperature of a refrigerant is required to be reduced as much as possible, and the heat exchange area of a condenser is required to be enlarged as much as possible. The method not only improves the energy consumption and the equipment investment, but also has low recovery rate of the 1,1,1-trifluoroacetone, and about 10 percent of trifluoroacetone can not be completely condensed and recovered.
Therefore, further improvements in the process for increasing the recovery of 1,1,1-trifluoroacetone are expected.
Disclosure of Invention
The invention aims to provide a method for improving the recovery rate of 1,1,1-trifluoroacetone, which can realize the efficient separation of 1,1,1-trifluoroacetone from ethylene and carbon dioxide in tail gas and has the characteristics of high recovery rate of 1,1,1-trifluoroacetone, low energy consumption and less equipment investment.
The invention adopts the following technical scheme:
a process for increasing recovery of 1,1,1-trifluoroacetone comprising:
(1) fully mixing the 1,1,1-trifluoroacetone tail gas with an organic solvent, wherein the boiling point of the organic solvent is higher than that of 1,1, 1-trifluoroacetone;
(2) and (2) rectifying the material obtained in the step (1) at the temperature of 30-110 ℃ to obtain the 1,1, 1-trifluoroacetone.
The boiling point of the organic solvent used in the invention is higher than that of 1,1, 1-trifluoroacetone. Preferably, the organic solvent is at least one selected from the group consisting of formate, haloformate, acetate, haloacetate, propionate, halopropionate, benzene, and benzene substituted with halogen, alkyl, or haloalkyl. The haloformate is a formate substituted by fluorine, chlorine, bromine or iodine. The haloacetate is an acetate substituted by a group selected from fluorine, chlorine, bromine or iodine. The halopropionate is propionate substituted by a substituent selected from fluorine, chlorine, bromine or iodine. Benzene substituted by halogen, alkyl or haloalkyl, i.e. benzene substituted on the benzene ring by halogen, alkyl or haloalkyl, said halogen being selected from fluorine, chlorine, bromine or iodine, said haloalkyl being alkyl substituted by a group selected from fluorine, chlorine, bromine or iodine. It is further preferred that the organic solvent is selected from at least one of ethyl acetate, ethyl trifluoroacetate, toluene and fluorobenzene. Still more preferably, the organic solvent is preferably at least one selected from ethyl acetate and ethyl trifluoroacetate.
The dosage of the organic solvent used in the invention is related to the content of 1,1,1-trifluoroacetone in the tail gas. Preferably, the molar ratio of the amount of the organic solvent to the 1,1,1-trifluoroacetone is 5-25: 1. Further preferably, the preferable molar ratio of the amount of the organic solvent to the 1,1,1-trifluoroacetone is 10-15: 1.
In the method provided by the invention, when the 1,1,1-trifluoroacetone tail gas and the organic solvent in the step (1) are fully mixed, the preferable mixing temperature is-10-25 ℃. Further preferably, the mixing temperature is 0 to 10 ℃.
In the method provided by the invention, the rectification temperature is 30-110 ℃ during the rectification in the step (2). Preferably, the rectification temperature is 30-70 ℃.
In the method provided by the invention, the rectified kettle liquid can be reused for absorbing 1,1,1-trifluoroacetone after being cooled to room temperature.
Detailed Description
The present invention is further illustrated by the following examples, which are not intended to limit the invention to these embodiments. It will be appreciated by those skilled in the art that the present invention encompasses all alternatives, modifications and equivalents as may be included within the scope of the claims.
Example 1
The tail gas absorption kettle has the volume of 500L and is provided with a stirring device, a thermometer, a metering tank, an air inlet pipe, a condenser and a module scale. 300.0kg (2.1kmol) of ethyl trifluoroacetate is added into the absorption kettle through a metering tank, and the temperature is reduced to 0 ℃ after the addition. Introducing industrial tail gas of 1,1,1-trifluoroacetone into an absorption kettle. After the trifluoroacetone device stops, the air inlet pipe is closed, and the weight of the display system is increased by 35.2kg by the module.
The volume of the rectifying kettle is 500L, the height of the tower is 5m, the inner diameter of the tower is 100mm, and Y-shaped ceramic corrugated packing is adopted. And transferring the absorption liquid obtained in the absorption kettle to a rectifying kettle for normal pressure rectification. The kettle temperature is controlled at 30-60 ℃, frozen brine at-10 ℃ is used as a refrigerant, and the reflux ratio is controlled to be 5. When the content of the 1,1,1-trifluoroacetone in the fraction is more than or equal to 99.0 percent, collecting a finished product, and when the content of the trifluoroacetone in the fraction is less than 99.0 percent, stopping rectification. Finally, 32.6kg of 1,1,1-trifluoroacetone with the content of 99.3 percent is obtained, and the recovery rate of the trifluoroacetone is 92.6 percent.
And cooling the kettle liquid to room temperature to obtain the kettle liquid which can be reused for absorbing the 1,1, 1-trifluoroacetone.
Example 2
The tail gas absorption kettle has the volume of 500L and is provided with a stirring device, a thermometer, a metering tank, an air inlet pipe, a condenser and a module scale. 264.0kg (3.0kmol) of ethyl acetate is added into the absorption kettle through a metering tank, and the temperature is reduced to 5 ℃ after the addition. The same industrial off-gas of 1,1,1-trifluoroacetone as in example 1 was introduced into an absorption vessel. After the trifluoroacetone device stops, the air inlet pipe is closed, and the weight of the display system is increased by 23.7 kg.
The volume of the rectifying kettle is 500L, the height of the tower is 5m, the inner diameter of the tower is 100mm, and Y-shaped ceramic corrugated packing is adopted. And transferring the absorption liquid obtained in the absorption kettle to a rectifying kettle for normal pressure rectification. The kettle temperature is controlled at 30-80 ℃, frozen brine at-10 ℃ is used as a refrigerant, and the reflux ratio is controlled to be 6. And (3) collecting the finished product when the content of the 1,1,1-trifluoroacetone in the fraction is more than or equal to 99.0%, and stopping rectification when the content of the 1,1,1-trifluoroacetone in the fraction is less than 99.0%. Finally, 21.5kg of 1,1,1-trifluoroacetone with the content of 99.4 percent is obtained, and the recovery rate of the trifluoroacetone is 90.7 percent.
And cooling the kettle liquid to room temperature to obtain the kettle liquid which can be reused for absorbing the 1,1, 1-trifluoroacetone.
Example 3
The tail gas absorption kettle has the volume of 500L and is provided with a stirring device, a thermometer, a metering tank, an air inlet pipe, a condenser and a module scale. 286.5kg (3.1kmol) of toluene are added into the absorption kettle through a metering tank, and then the temperature is reduced to 10 ℃. Introducing industrial tail gas of the trifluoroacetone into an absorption kettle. After the trifluoroacetone device stops, the air inlet pipe is closed, and the weight of the display system is increased by 28.7kg by the module.
The volume of the rectifying kettle is 500L, the height of the tower is 5m, the inner diameter of the tower is 100mm, and Y-shaped ceramic corrugated packing is adopted. And transferring the absorption liquid obtained in the absorption kettle to a rectifying kettle for normal pressure rectification. The kettle temperature is controlled at 30-110 ℃, frozen brine at-10 ℃ is used as a refrigerant, and the reflux ratio is controlled to be 5. And when the content of the trifluoroacetone in the fraction is more than or equal to 99.0 percent, collecting a finished product, and when the content of the trifluoroacetone in the fraction is less than 99.0 percent, stopping rectification. 27.6kg of trifluoroacetone with the content of 99.2 percent is finally obtained, and the recovery rate of the trifluoroacetone is 96.2 percent.
And cooling the kettle liquid to room temperature to obtain the kettle liquid which can be reused for absorbing the 1,1, 1-trifluoroacetone.
Example 4
The tail gas absorption kettle has the volume of 500L and is provided with a stirring device, a thermometer, a metering tank, an air inlet pipe, a condenser and a module scale. 300.8kg (3.1kmol) of fluorobenzene is added into the absorption kettle through a metering tank, and the temperature is reduced to-5 ℃ after the addition is finished. Introducing industrial tail gas of the trifluoroacetone into an absorption kettle. After the trifluoroacetone device stops, the air inlet pipe is closed, and the weight of the display system is increased by 29.6kg by the module.
The volume of the rectifying kettle is 500L, the height of the tower is 5m, the inner diameter of the tower is 100mm, and Y-shaped ceramic corrugated packing is adopted. And transferring the absorption liquid obtained in the absorption kettle to a rectifying kettle for normal pressure rectification. The kettle temperature is controlled at 30-86 ℃, frozen brine at-10 ℃ is used as a refrigerant, and the reflux ratio is controlled to be 4. And when the content of the trifluoroacetone in the fraction is more than or equal to 99.0 percent, collecting a finished product, and when the content of the trifluoroacetone in the fraction is less than 99.0 percent, stopping rectification. 28.3kg of trifluoroacetone with a content of 99.5% is finally obtained. After the kettle liquid is cooled to room temperature, the obtained kettle liquid can be reused for absorbing the 1,1,1-trifluoroacetone, and the recovery rate of the trifluoroacetone is 95.6%.
Comparative example 1
Methanesulfonic acid (576kg, 6kmol) was added to a 1 cubic meter reactor equipped with an electric stirring device, a thermometer, a feed tank and a reflux condenser (the refrigerant was chilled brine at-10 ℃ to-5 ℃). The reactor was heated and ethyl 4,4, 4-trifluoroacetoacetate (552kg, 3kmol) was slowly added to the reaction as the addition of trifluoroacetone continued to occur and was condensed in a condenser when the temperature of methanesulfonic acid was 100 ℃. Finally, 300.5kg of trifluoroacetone with the content of 99.2 percent is collected in a product collecting tank, and the yield is 88.7 percent.
Claims (6)
1. A process for increasing the recovery of 1,1,1-trifluoroacetone, characterized in that the process comprises:
(1) fully mixing the 1,1,1-trifluoroacetone tail gas with an organic solvent, wherein the boiling point of the organic solvent is higher than that of the 1,1,1-trifluoroacetone, and the organic solvent is selected from at least one of ethyl acetate, ethyl trifluoroacetate, toluene and fluorobenzene;
(2) rectifying the material obtained in the step (1) at the temperature of 30-110 ℃ to obtain 1,1, 1-trifluoroacetone;
the molar ratio of the amount of the organic solvent to the 1,1,1-trifluoroacetone is 5-25: 1.
2. The method for increasing recovery of 1,1,1-trifluoroacetone according to claim 1, characterized in that the organic solvent is selected from at least one of ethyl acetate and ethyl trifluoroacetate.
3. The method for improving the recovery rate of 1,1,1-trifluoroacetone according to claim 1, characterized in that the preferred molar ratio of the amount of the organic solvent to 1,1,1-trifluoroacetone is 10-15: 1.
4. The method for improving the recovery rate of 1,1,1-trifluoroacetone according to claim 1, characterized in that the mixing temperature in the step (1) is-10 to 25 ℃.
5. The method for improving the recovery rate of 1,1,1-trifluoroacetone according to claim 4, characterized in that in the step (1), the preferred mixing temperature is 0-10 ℃.
6. The method for improving the recovery rate of 1,1,1-trifluoroacetone according to claim 1, characterized in that in the step (2), the preferred rectification temperature is 30-70 ℃.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610115486.2A CN107141210B (en) | 2016-03-01 | 2016-03-01 | Method for improving recovery rate of trifluoroacetone |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610115486.2A CN107141210B (en) | 2016-03-01 | 2016-03-01 | Method for improving recovery rate of trifluoroacetone |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107141210A CN107141210A (en) | 2017-09-08 |
| CN107141210B true CN107141210B (en) | 2021-02-23 |
Family
ID=59783108
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610115486.2A Active CN107141210B (en) | 2016-03-01 | 2016-03-01 | Method for improving recovery rate of trifluoroacetone |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107141210B (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5481029A (en) * | 1993-04-27 | 1996-01-02 | Solvay Fluor Und Derivate Gmbh | Process for preparation of ketones |
-
2016
- 2016-03-01 CN CN201610115486.2A patent/CN107141210B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5481029A (en) * | 1993-04-27 | 1996-01-02 | Solvay Fluor Und Derivate Gmbh | Process for preparation of ketones |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107141210A (en) | 2017-09-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| MY160862A (en) | Process for producing acetic acid | |
| CN113429267B (en) | Continuous process and device for preparing o-phenylphenol | |
| CN102557932B (en) | Method for producing isobutyl acetate | |
| AR075487A1 (en) | PROCESS FOR SEPARATING VINYL ACETATE FROM A GAS MIXTURE FORMED BY REACTION OF ETHYLENE WITH ACETIC ACID AND OXYGEN | |
| CN103012183A (en) | Preparation method of N,-N-diethyl-formamide | |
| CN103694119A (en) | Preparation method of ethyl 4,4,4-trifluoroacetoacetate | |
| CN113461614A (en) | Preparation method of caprolactam | |
| CN107141210B (en) | Method for improving recovery rate of trifluoroacetone | |
| CN102702122B (en) | Method for preparing tetrazine by oxidizing dihydro tetrazine | |
| CN103058984B (en) | Synthesis method of watermelon ketone | |
| CN101880230A (en) | Preparation method of 2,4-dibromo-butyricacid methyl ester | |
| CN101306980B (en) | Method for preparing perchloro cyclopentadiene | |
| CN114100551B (en) | Production device and production process of dimeric thiohexafluoroacetone | |
| CN104529698A (en) | Preparation method for bromopentafluorobenzene | |
| CN102211996A (en) | Preparation method of 2,5-dihydroxy terephthalic acid | |
| WO2022134489A1 (en) | Full continuous flow synthesis process of fluorine-containing aromatic hydrocarbon compound | |
| CN116239496A (en) | Method for continuously preparing heptafluoroisobutyronitrile | |
| US20180305288A1 (en) | Method of preparing (meth)acrylic acid | |
| CN106831405A (en) | The preparation method of 2,2 2 fluoracyl fluorides and its derivative | |
| CN106699610A (en) | Process and device for producing dimethyl sulfate with low methyl ether content | |
| CN107867992A (en) | A kind of method for synthesizing Phenoxiacetic acid derivatives | |
| CN113735712B (en) | Preparation method of o-nitrobenzaldehyde | |
| CN104292104A (en) | Method and device for preparing methyl fluoroacetate | |
| CN108929211A (en) | A kind of synthesizer and method of vitamin A intermediate 2-methyl-4-(2,6,6-trimethyl-1-cyclohexen-1-yl)-2-butenal | |
| US9115067B1 (en) | Process for the manufacture of acrolein |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |