CN111960973A - Process for extracting diphenyl sulfone from benzene sulfonyl chloride tailings - Google Patents
Process for extracting diphenyl sulfone from benzene sulfonyl chloride tailings Download PDFInfo
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- CN111960973A CN111960973A CN202010902259.0A CN202010902259A CN111960973A CN 111960973 A CN111960973 A CN 111960973A CN 202010902259 A CN202010902259 A CN 202010902259A CN 111960973 A CN111960973 A CN 111960973A
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- diphenyl
- sulfonyl chloride
- benzene sulfonyl
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C315/00—Preparation of sulfones; Preparation of sulfoxides
- C07C315/06—Separation; Purification; Stabilisation; Use of additives
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C315/00—Preparation of sulfones; Preparation of sulfoxides
- C07C315/02—Preparation of sulfones; Preparation of sulfoxides by formation of sulfone or sulfoxide groups by oxidation of sulfides, or by formation of sulfone groups by oxidation of sulfoxides
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Abstract
The invention discloses a process for extracting diphenyl sulfone from benzene sulfonyl chloride tailings, which comprises the following steps: 1) primary separation: first taking benzene sulfonyl chloride tailing, filtering the solution containing the diphenyl sulfoxide through filter paper, and 2) evaporating: adding the solution after the primary separation into a vacuum machine for evaporation, turning on a heater to control the temperature to be 19-22 ℃, evaporating the solution containing the diphenyl sulfoxide, and collecting the steam containing the diphenyl sulfoxide by external collection equipment; 3) and (3) rectification: gradually cooling and decompressing the collected diphenyl sulfoxide steam, separating and collecting diphenyl sulfoxide liquid; 4) and (3) oxidation: adding the collected diphenyl sulfoxide after rectification into water, stirring by a stirrer, adding a hydrogen peroxide solution to adjust the pH value to 5-6, heating to 140-150 ℃, stirring for 1.5-3h, extracting diphenyl sulfone from benzene sulfonyl chloride tailings by a diphenyl sulfone tailing extraction process, and finally preparing the diphenyl sulfone, wherein the procurement cost is low and the processing efficiency is high.
Description
Technical Field
The invention relates to the technical field of diphenyl sulfone extraction, in particular to a process for extracting diphenyl sulfone from benzene sulfonyl chloride tailings.
Background
The benzene sulfonyl chloride is colorless transparent oily liquid, is mainly used for organic synthesis, preparation of sulfonamide and identification of various amines, is unstable, is placed in the air when being opened, can absorb a large amount of water in the air when being placed in the air, and is gradually hydrolyzed to reduce the pH value. The volatilized hydrogen chloride can form white smoke and has strong irritation, the synthesis of industrial benzene sulfonyl chloride can use benzene sulfonic acid as a raw material to prepare benzene sulfonate through reaction, the benzene sulfonate is obtained through purification, the benzene sulfonyl chloride is prepared through reaction with a chlorination reagent in a solvent, and the solvent often contains toluene, diphenyl sulfoxide, N-diphenylformamide and the like, so the tailing of the benzene sulfonyl chloride processing often contains unreacted diphenyl sulfoxide;
diphenyl sulfone, as an organic sulfide, has the ability to enhance insulin production in the human body, plays a role in promoting the metabolism of saccharides, is also a necessary substance for the synthesis of collagen of the human body, can also promote wound healing, can also play a role in the synthesis and activation of vitamin B, vitamin C and biotin required by metabolism and nerve health, and is called as a 'natural beautifying carbon substance';
at present, the domestic industrial production method of diphenyl sulfone is mainly obtained by oxidizing diphenyl sulfoxide by nitric acid, and the conventional procurement of diphenyl sulfoxide has higher processing cost.
Disclosure of Invention
The technical problem to be solved by the invention is to overcome the defects in the prior art, provide a process for extracting diphenyl sulfone from benzene sulfonyl chloride tailings, extract diphenyl sulfoxide from the benzene sulfonyl chloride tailings to finally prepare diphenyl sulfone, have low purchase cost and high processing efficiency, and can effectively solve the problems in the background art.
In order to achieve the purpose, the invention provides the following technical scheme: the process for extracting diphenyl sulfone from benzene sulfonyl chloride tailings comprises the following steps:
1) primary separation: firstly taking benzene sulfonyl chloride tailing, filtering the solution containing the diphenyl sulfoxide through filter paper,
2) and (3) evaporation: adding the solution after the primary separation into a vacuum machine for evaporation, turning on a heater to control the temperature to be 19-22 ℃, evaporating the solution containing the diphenyl sulfoxide, and collecting the steam containing the diphenyl sulfoxide by external collection equipment;
3) and (3) rectification: gradually cooling and decompressing the collected diphenyl sulfoxide steam, separating and collecting diphenyl sulfoxide liquid;
4) and (3) oxidation: adding the collected diphenyl sulfoxide after rectification into water, stirring by a stirrer, adding a hydrogen peroxide solution to adjust the pH value to 5-6, heating to 140-;
5) and (3) crystallization: feeding the diphenyl sulfone generated after oxidation into a rinsing kettle for rinsing, and feeding the rinsed material into a reduced pressure distillation kettle; distilling in a distillation kettle, controlling the vacuum degree to be more than or equal to 0.096MPa, the distillation temperature to be 160-.
Furthermore, the vacuum degree in the evaporation process is more than or equal to 0.094 MPa.
Further, in the rectification process, the lower layer of the water-washed standing solution is placed into a rectification kettle, and is subjected to vacuum rectification at the temperature of 230-240 ℃, and the fraction at 150 ℃/-0.098MPa is collected.
Further, in the oxidation process, the solute mass fraction of the hydrogen peroxide solution is 50%, the reaction temperature is controlled at 130-140 ℃, and the reaction retention time is 13-16 min.
Further, during the oxidation process, the speed of the stirrer is controlled at 280-300r/min, and the temperature is controlled by a water bath during stirring, so that the temperature is 20-25 ℃.
Further, in the oxidation process, the solution of mixed water of diphenyl sulfoxide and hydrogen peroxide solution can be placed into a microchannel reactor for processing.
Further, in the oxidation process, the diphenyl sulfoxide is mixed with water in a dropwise adding mode, the dropwise adding speed is firstly slow and then fast, the dropwise adding amount is 50-200kg per hour, the reaction temperature is controlled to be less than 50 ℃, the hydrolysis and dilution time is 3.5 hours, and then the materials are kept stand.
Furthermore, the temperature is controlled between 16 ℃ and 18 ℃ in the crystallization process, and the vacuum degree is more than or equal to 0.096 MPa.
Compared with the prior art, the invention has the beneficial effects that: the process for extracting diphenyl sulfone from benzene sulfonyl chloride tailings has the following advantages:
in the preparation process of the benzenesulfonyl chloride, a reaction solvent of the benzenesulfonyl chloride often contains toluene, diphenyl sulfoxide, N-diphenylformamide and the like, the diphenyl sulfoxide is separated and collected to finally prepare the diphenyl sulfone, the high-purity diphenyl sulfoxide does not need to be purchased, the purchase cost is reduced, and the finally extracted diphenyl sulfone has high purity and good quality.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention provides the following technical scheme:
the first embodiment is as follows:
the process for extracting diphenyl sulfone from benzene sulfonyl chloride tailings comprises the following steps:
1) primary separation: firstly taking benzene sulfonyl chloride tailing, filtering the solution containing the diphenyl sulfoxide through filter paper,
2) and (3) evaporation: adding the solution after the primary separation into a vacuum machine for evaporation, turning on a heater to control the temperature to be 19 ℃, evaporating the solution containing the diphenyl sulfoxide, and collecting the steam containing the diphenyl sulfoxide by external collection equipment;
the vacuum degree is more than or equal to 0.094MPa in the evaporation process;
3) and (3) rectification: gradually cooling and decompressing the collected diphenyl sulfoxide steam, separating and collecting diphenyl sulfoxide liquid;
in the rectification process, the lower layer of the water-washed standing solution is placed in a rectification kettle, and is rectified under reduced pressure at the temperature of 230 ℃, and the fraction at the temperature of 150 +/-0.098 MPa is collected;
4) and (3) oxidation: adding the collected diphenyl sulfoxide after rectification into water, stirring by a stirrer, adding a hydrogen peroxide solution to adjust the pH to 5, heating to 140 ℃, and stirring for 1.5 hours to generate diphenyl sulfone;
in the oxidation process, the solute mass fraction of the hydrogen peroxide solution is 50%, the reaction temperature is controlled at 130 ℃, and the reaction retention time is 13 min;
in the oxidation process, the speed of the stirrer is controlled at 280r/min, and the temperature is controlled by water bath during stirring to be 20 ℃;
in the oxidation process, the solution after the mixed water of the diphenyl sulfoxide and the hydrogen peroxide solution can be placed into a microchannel reactor for processing;
in the oxidation process, the diphenyl sulfoxide is mixed with water in a dropwise adding mode, the dropwise adding speed is slow firstly and then 50kg of the diphenyl sulfoxide is added per hour quickly, the reaction temperature is controlled to be less than 50 ℃, the hydrolysis and dilution time is 3.5 hours, and then the materials are kept stand;
5) and (3) crystallization: feeding the diphenyl sulfone generated after oxidation into a rinsing kettle for rinsing, and feeding the rinsed material into a reduced pressure distillation kettle; distilling with a distillation still, controlling the vacuum degree to be more than or equal to 0.096MPa, the distillation temperature to be 160 ℃, controlling the time to be 3h, finally crystallizing to obtain white crystals, and collecting;
the temperature is controlled at 16 ℃ in the crystallization process, and the vacuum degree is more than or equal to 0.096 MPa.
Example two:
the process for extracting diphenyl sulfone from benzene sulfonyl chloride tailings comprises the following steps:
1) primary separation: firstly taking benzene sulfonyl chloride tailing, filtering the solution containing the diphenyl sulfoxide through filter paper,
2) and (3) evaporation: adding the solution after the primary separation into a vacuum machine for evaporation, turning on a heater to control the temperature to be 20 ℃, evaporating the solution containing the diphenyl sulfoxide, and collecting the steam containing the diphenyl sulfoxide by external collection equipment;
the vacuum degree is more than or equal to 0.094MPa in the evaporation process;
3) and (3) rectification: gradually cooling and decompressing the collected diphenyl sulfoxide steam, separating and collecting diphenyl sulfoxide liquid;
in the rectification process, the lower layer of the water-washed standing solution is placed in a rectification kettle, rectification is carried out under reduced pressure at the temperature of 234 ℃, and the fraction at 150 +/-0.098 MPa is collected;
4) and (3) oxidation: adding the collected diphenyl sulfoxide after rectification into water, stirring by a stirrer, adding a hydrogen peroxide solution to adjust the pH to 5.4, heating to 145 ℃, and stirring for 1.8h to generate diphenyl sulfone;
in the oxidation process, the solute mass fraction of the hydrogen peroxide solution is 50%, the reaction temperature is controlled at 132 ℃, and the reaction retention time is 14 min;
in the oxidation process, the speed of the stirrer is controlled at 290r/min, and the temperature is controlled by water bath during stirring to be 21 ℃;
in the oxidation process, the solution after the mixed water of the diphenyl sulfoxide and the hydrogen peroxide solution can be placed into a microchannel reactor for processing;
in the oxidation process, the diphenyl sulfoxide is mixed with water in a dropwise adding mode, the dropwise adding speed is slow firstly, then the dropwise adding amount is 60kg per hour, the reaction temperature is controlled to be less than 50 ℃, the hydrolysis and dilution time is 3.5 hours, and then the materials are kept stand;
5) and (3) crystallization: feeding the diphenyl sulfone generated after oxidation into a rinsing kettle for rinsing, and feeding the rinsed material into a reduced pressure distillation kettle; distilling with a distillation still, controlling the vacuum degree to be more than or equal to 0.096MPa, the distillation temperature to be 168 ℃, controlling the time to be 3.2h, finally crystallizing to obtain white crystals, and collecting;
the temperature is controlled at 16-18 ℃ in the crystallization process, and the vacuum degree is more than or equal to 0.096 MPa.
Example three:
the process for extracting diphenyl sulfone from benzene sulfonyl chloride tailings comprises the following steps:
1) primary separation: firstly taking benzene sulfonyl chloride tailing, filtering the solution containing the diphenyl sulfoxide through filter paper,
2) and (3) evaporation: adding the solution after the primary separation into a vacuum machine for evaporation, turning on a heater to control the temperature to be 21 ℃, evaporating the solution containing the diphenyl sulfoxide, and collecting the steam containing the diphenyl sulfoxide by external collection equipment;
the vacuum degree is more than or equal to 0.094MPa in the evaporation process;
3) and (3) rectification: gradually cooling and decompressing the collected diphenyl sulfoxide steam, separating and collecting diphenyl sulfoxide liquid;
in the rectification process, the lower layer of the water-washed standing solution is placed in a rectification kettle, rectification is carried out under reduced pressure at the temperature of 236 ℃, and the fraction with the temperature of 150 +/-0.098 MPa is collected;
4) and (3) oxidation: adding the collected diphenyl sulfoxide after rectification into water, stirring by a stirrer, adding a hydrogen peroxide solution to adjust the pH to 5.8, heating to 148 ℃, and stirring for 2 hours to generate diphenyl sulfone;
in the oxidation process, the solute mass fraction of the hydrogen peroxide solution is 50%, the reaction temperature is controlled at 137 ℃, and the reaction retention time is 15 min;
in the oxidation process, the speed of the stirrer is controlled at 280-300r/min, and the temperature is controlled by water bath during stirring to be 23 ℃;
in the oxidation process, the solution after the mixed water of the diphenyl sulfoxide and the hydrogen peroxide solution can be placed into a microchannel reactor for processing;
in the oxidation process, the diphenyl sulfoxide is mixed with water in a dropwise adding mode, the dropwise adding speed is slow firstly and then is high, the dropwise adding amount is 150kg per hour, the reaction temperature is controlled to be less than 50 ℃, the hydrolysis and dilution time is 3.5 hours, and then the materials are kept stand;
5) and (3) crystallization: feeding the diphenyl sulfone generated after oxidation into a rinsing kettle for rinsing, and feeding the rinsed material into a reduced pressure distillation kettle; distilling with a distillation still, controlling the vacuum degree to be more than or equal to 0.096MPa, the distillation temperature to be 174 ℃, controlling the time to be 3.7h, finally crystallizing to obtain white crystals, and collecting;
the temperature is controlled at 17.5 ℃ in the crystallization process, and the vacuum degree is more than or equal to 0.096 MPa.
Example four:
the process for extracting diphenyl sulfone from benzene sulfonyl chloride tailings comprises the following steps:
1) primary separation: firstly taking benzene sulfonyl chloride tailing, filtering the solution containing the diphenyl sulfoxide through filter paper,
2) and (3) evaporation: adding the solution after the primary separation into a vacuum machine for evaporation, turning on a heater to control the temperature to be 22 ℃, evaporating the solution containing the diphenyl sulfoxide, and collecting the steam containing the diphenyl sulfoxide by external collection equipment;
the vacuum degree is more than or equal to 0.094MPa in the evaporation process;
3) and (3) rectification: gradually cooling and decompressing the collected diphenyl sulfoxide steam, separating and collecting diphenyl sulfoxide liquid;
in the rectification process, the lower layer of the water-washed standing solution is placed in a rectification kettle, and is rectified under reduced pressure at the temperature of 240 ℃, and the fraction at 150 ℃ under +/-0.098 MPa is collected;
4) and (3) oxidation: adding the collected diphenyl sulfoxide after rectification into water, stirring by a stirrer, adding a hydrogen peroxide solution to adjust the pH to 6, heating to 150 ℃, and stirring for 3 hours to generate diphenyl sulfone;
in the oxidation process, the solute mass fraction of the hydrogen peroxide solution is 50%, the reaction temperature is controlled at 140 ℃, and the reaction retention time is 16 min;
in the oxidation process, the speed of the stirrer is controlled at 280-300r/min, and the temperature is controlled through water bath during stirring to be 25 ℃;
in the oxidation process, the solution after the mixed water of the diphenyl sulfoxide and the hydrogen peroxide solution can be placed into a microchannel reactor for processing;
in the oxidation process, the diphenyl sulfoxide is mixed with water in a dropwise adding mode, the dropwise adding speed is slow firstly and then 200kg of the diphenyl sulfoxide is added per hour quickly, the reaction temperature is controlled to be less than 50 ℃, the hydrolysis and dilution time is 3.5 hours, and then the materials are kept stand;
5) and (3) crystallization: feeding the diphenyl sulfone generated after oxidation into a rinsing kettle for rinsing, and feeding the rinsed material into a reduced pressure distillation kettle; distilling with a distillation still, controlling the vacuum degree to be more than or equal to 0.096MPa, the distillation temperature to be 180 ℃, controlling the time to be 4h, finally crystallizing to obtain white crystals, and collecting;
the temperature is controlled at 18 ℃ in the crystallization process, and the vacuum degree is more than or equal to 0.096 MPa.
It is noted that diphenyl sulfone is diphenyl sulfone.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (8)
1. The process for extracting diphenyl sulfone from benzene sulfonyl chloride tailings is characterized by comprising the following steps of:
1) primary separation: firstly taking benzene sulfonyl chloride tailing, filtering the solution containing the diphenyl sulfoxide through filter paper,
2) and (3) evaporation: adding the solution after the primary separation into a vacuum machine for evaporation, turning on a heater to control the temperature to be 19-22 ℃, evaporating the solution containing the diphenyl sulfoxide, and collecting the steam containing the diphenyl sulfoxide by external collection equipment;
3) and (3) rectification: gradually cooling and decompressing the collected diphenyl sulfoxide steam, separating and collecting diphenyl sulfoxide liquid;
4) and (3) oxidation: adding the collected diphenyl sulfoxide after rectification into water, stirring by a stirrer, adding a hydrogen peroxide solution to adjust the pH value to 5-6, heating to 140-;
5) and (3) crystallization: feeding the diphenyl sulfone generated after oxidation into a rinsing kettle for rinsing, and feeding the rinsed material into a reduced pressure distillation kettle; distilling in a distillation kettle, controlling the vacuum degree to be more than or equal to 0.096MPa, the distillation temperature to be 160-.
2. The process for extracting diphenyl sulfone from benzene sulfonyl chloride tailings as claimed in claim 1, wherein: the vacuum degree in the evaporation process is more than or equal to 0.094 MPa.
3. The process for extracting diphenyl sulfone from benzene sulfonyl chloride tailings as claimed in claim 1, wherein: in the rectification process, the lower layer of the water-washed standing solution is placed in a rectification kettle, and is subjected to vacuum rectification at the temperature of 230-240 ℃, and the fraction at 150 ℃/-0.098MPa is collected.
4. The process for extracting diphenyl sulfone from benzene sulfonyl chloride tailings as claimed in claim 1, wherein: in the oxidation process, the solute mass fraction of the hydrogen peroxide solution is 50%, the reaction temperature is controlled at 130-140 ℃, and the reaction residence time is 13-16 min.
5. The process for extracting diphenyl sulfone from benzene sulfonyl chloride tailings as claimed in claim 1, wherein: in the oxidation process, the speed of the stirrer is controlled at 280-300r/min, and the temperature is controlled by a water bath during stirring to be 20-25 ℃.
6. The process for extracting diphenyl sulfone from benzene sulfonyl chloride tailings as claimed in claim 1, wherein: in the oxidation process, the solution of mixed diphenyl sulfoxide and water and the hydrogen peroxide solution can be placed into a microchannel reactor for processing.
7. The process for extracting diphenyl sulfone from benzene sulfonyl chloride tailings as claimed in claim 1, wherein: in the oxidation process, the diphenyl sulfoxide is mixed with water in a dropping mode, the dropping speed is slow firstly, then the dropping amount is 50-200kg per hour quickly, the reaction temperature is controlled to be less than 50 ℃, the hydrolysis dilution time is 3.5 hours, and then the materials are kept stand.
8. The process for extracting diphenyl sulfone from benzene sulfonyl chloride tailings as claimed in claim 1, wherein: the temperature is controlled at 16-18 ℃ in the crystallization process, and the vacuum degree is more than or equal to 0.096 MPa.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB717725A (en) * | 1951-07-25 | 1954-11-03 | Universal Oil Prod Co | Improvements in or relating to the separation of mixtures of organic compounds |
| CN101195595A (en) * | 2007-12-12 | 2008-06-11 | 湖北兴发化工集团股份有限公司 | Method for recycling dimethyl sulfone and sodium nitrate from dimethyl sulfoxide waste slag |
| CN104592067A (en) * | 2015-01-30 | 2015-05-06 | 湖北大学 | Method for recycling dimethyl sulfoxide waste residue through multi-stage extraction |
| JP2018177666A (en) * | 2017-04-07 | 2018-11-15 | 東レ・ファインケミカル株式会社 | Method of recovering dimethyl sulfoxide |
-
2020
- 2020-09-01 CN CN202010902259.0A patent/CN111960973B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB717725A (en) * | 1951-07-25 | 1954-11-03 | Universal Oil Prod Co | Improvements in or relating to the separation of mixtures of organic compounds |
| CN101195595A (en) * | 2007-12-12 | 2008-06-11 | 湖北兴发化工集团股份有限公司 | Method for recycling dimethyl sulfone and sodium nitrate from dimethyl sulfoxide waste slag |
| CN104592067A (en) * | 2015-01-30 | 2015-05-06 | 湖北大学 | Method for recycling dimethyl sulfoxide waste residue through multi-stage extraction |
| JP2018177666A (en) * | 2017-04-07 | 2018-11-15 | 東レ・ファインケミカル株式会社 | Method of recovering dimethyl sulfoxide |
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