CN111960973B - 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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- CN111960973B CN111960973B CN202010902259.0A CN202010902259A CN111960973B CN 111960973 B CN111960973 B CN 111960973B CN 202010902259 A CN202010902259 A CN 202010902259A CN 111960973 B CN111960973 B CN 111960973B
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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 a solution containing 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, 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 of enhancing insulin production in the human body, plays a role in promoting the metabolism of saccharides, is also a necessary substance for synthesizing human collagen, can promote wound healing, can also play a role in synthesizing and activating 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 a solution containing 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 to 5-6, heating to 140-150 ℃, and stirring for 1.5-3h to generate diphenyl sulfone;
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 160-180 ℃, controlling the time to be 3-4h, finally crystallizing to obtain white crystals, and collecting.
Furthermore, the vacuum degree in the evaporation process is more than or equal to 0.094MPa.
Further, in the rectification process, the lower layer of the water-washed standing solution is placed into a rectification kettle, and is rectified under reduced pressure at the temperature of 230-240 ℃, and the fraction at 150 ℃/-0.098MPa is collected.
Furthermore, 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 13-16min.
Further, in the oxidation process, the speed of a stirrer is controlled at 280-300r/min, and the temperature is controlled by a water bath during stirring to be 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 temperature is controlled to be less than 50 ℃, the diluting 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 0.096MPa.
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, diphenyl sulfoxide is separated and collected to finally prepare the diphenyl sulfone, high-purity diphenyl sulfoxide does not need to be purchased, the purchase cost is reduced, and 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 a solution containing 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 in the evaporation process is more than or equal to 0.094MPa;
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 of 150 ℃/-0.098MPa 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 13min;
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 of mixed diphenyl sulfoxide and 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 firstly slow, then the dropwise adding amount is 50kg per hour, the temperature is controlled to be less than 50 ℃, the diluting 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 0.096MPa.
The second embodiment:
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 a solution containing 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 fractions at 150 +/-0.098 MPa are 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 14min;
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 of mixed diphenyl sulfoxide and 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 firstly slow, then the dropwise adding amount is 60kg per hour, the temperature is controlled to be less than 50 ℃, the diluting time is 3.5 hours, and then the materials are kept stand;
5) And (3) crystallization: delivering the diphenyl sulfone generated after oxidation into a rinsing kettle for rinsing, and delivering 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 0.096MPa.
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 a solution containing 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 through 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 fractions at 150 ℃/-0.098MPa are 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 15min;
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 of mixed diphenyl sulfoxide and 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 150kg per hour quickly, the temperature is controlled to be less than 50 ℃, the 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 0.096MPa.
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 a solution containing 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 in the evaporation process is more than or equal to 0.094MPa;
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 value 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 16min;
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 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 temperature is controlled to be less than 50 ℃, the 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 0.096MPa.
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 various 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 (5)
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 a solution containing 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, placing the lower layer of the water-washed standing solution into a rectifying still in the rectifying process, decompressing and rectifying at 230-240 ℃, and collecting 150 ℃/-0.098MPa fraction;
4) And (3) oxidation: adding the collected diphenyl sulfoxide after rectification into water, stirring by a stirrer, controlling the speed of the stirrer at 280-300r/min, controlling the temperature by water bath during stirring to enable the temperature to be 20-25 ℃, adding a hydrogen peroxide solution after stirring to adjust the pH to 5-6, heating to 140-150 ℃, stirring for 1.5-3h, controlling the mass fraction of a solute of the hydrogen peroxide solution to be 50%, controlling the reaction temperature to be 130-140 ℃ after stirring, and keeping the reaction time to be 13-16min to generate diphenyl sulfone;
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 still, controlling the vacuum degree to be more than or equal to 0.096MPa, the distillation temperature to be 160-180 ℃ and the time to be 3-4h, finally crystallizing to obtain white crystals, and collecting.
2. The process for extracting diphenyl sulfone from benzene sulfonyl chloride tailings as claimed in claim 1, wherein the process comprises the following steps: the vacuum degree in the evaporation process is more than or equal to 0.094MPa.
3. The process for extracting diphenyl sulfone from benzene sulfonyl chloride tailings as claimed in claim 1, wherein the process comprises the following steps: in the oxidation process, the solution of mixed diphenyl sulfoxide and hydrogen peroxide solution can be placed into a microchannel reactor for processing.
4. 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 temperature is controlled to be less than 50 ℃, the dilution time is 3.5 hours, and then the materials are kept stand.
5. 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 0.096MPa.
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| GB717725A (en) * | 1951-07-25 | 1954-11-03 | Universal Oil Prod Co | Improvements in or relating to the separation of mixtures of organic compounds |
| CN101195595B (en) * | 2007-12-12 | 2012-02-01 | 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 |
| CN104592067B (en) * | 2015-01-30 | 2016-08-24 | 湖北大学 | A kind of method that multitple extraction dimethyl sulfoxide waste residue recycles |
| JP6795798B2 (en) * | 2017-04-07 | 2020-12-02 | 東レ・ファインケミカル株式会社 | How to recover dimethyl sulfoxide |
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