CN112321468A - Method for separating dimethyl sulfoxide from wastewater generated in synthesis process of ether azole drugs - Google Patents
Method for separating dimethyl sulfoxide from wastewater generated in synthesis process of ether azole drugs Download PDFInfo
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- CN112321468A CN112321468A CN202011108552.6A CN202011108552A CN112321468A CN 112321468 A CN112321468 A CN 112321468A CN 202011108552 A CN202011108552 A CN 202011108552A CN 112321468 A CN112321468 A CN 112321468A
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- CN
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- Prior art keywords
- dimethyl sulfoxide
- synthesis process
- entrainer
- wastewater
- azole drugs
- Prior art date
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- IAZDPXIOMUYVGZ-UHFFFAOYSA-N Dimethylsulphoxide Chemical compound CS(C)=O IAZDPXIOMUYVGZ-UHFFFAOYSA-N 0.000 title claims abstract description 138
- 238000000034 method Methods 0.000 title claims abstract description 51
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 title claims abstract description 36
- KAESVJOAVNADME-UHFFFAOYSA-N Pyrrole Chemical compound C=1C=CNC=1 KAESVJOAVNADME-UHFFFAOYSA-N 0.000 title claims abstract description 36
- 239000002351 wastewater Substances 0.000 title claims abstract description 30
- 239000003814 drug Substances 0.000 title claims abstract description 19
- 229940079593 drug Drugs 0.000 title claims abstract description 16
- 230000015572 biosynthetic process Effects 0.000 title claims abstract description 13
- 238000003786 synthesis reaction Methods 0.000 title claims abstract description 13
- 238000004821 distillation Methods 0.000 claims abstract description 15
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Natural products CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 claims description 16
- 239000012074 organic phase Substances 0.000 claims description 5
- 239000012071 phase Substances 0.000 claims description 3
- 230000002194 synthesizing effect Effects 0.000 claims description 2
- 125000003944 tolyl group Chemical group 0.000 claims description 2
- 230000008901 benefit Effects 0.000 abstract description 7
- 238000004519 manufacturing process Methods 0.000 abstract description 7
- 230000007613 environmental effect Effects 0.000 abstract description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 19
- 238000000926 separation method Methods 0.000 description 12
- 239000007788 liquid Substances 0.000 description 10
- 238000010533 azeotropic distillation Methods 0.000 description 6
- 238000010438 heat treatment Methods 0.000 description 5
- 238000001704 evaporation Methods 0.000 description 4
- 238000004817 gas chromatography Methods 0.000 description 4
- 238000000746 purification Methods 0.000 description 4
- 238000005070 sampling Methods 0.000 description 4
- 229910001220 stainless steel Inorganic materials 0.000 description 4
- 239000010935 stainless steel Substances 0.000 description 4
- 238000003756 stirring Methods 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- 239000003795 chemical substances by application Substances 0.000 description 3
- 239000007791 liquid phase Substances 0.000 description 3
- 239000002904 solvent Substances 0.000 description 3
- 239000012808 vapor phase Substances 0.000 description 3
- 238000004458 analytical method Methods 0.000 description 2
- 239000003153 chemical reaction reagent Substances 0.000 description 2
- 239000012043 crude product Substances 0.000 description 2
- 238000002425 crystallisation Methods 0.000 description 2
- 230000008025 crystallization Effects 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000008020 evaporation Effects 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000010924 continuous production Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000003869 coulometry Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000006837 decompression Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000004043 dyeing Methods 0.000 description 1
- -1 electronics Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002309 gasification Methods 0.000 description 1
- 239000002808 molecular sieve Substances 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 239000002798 polar solvent Substances 0.000 description 1
- 238000007639 printing Methods 0.000 description 1
- 239000012264 purified product Substances 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- URGAHOPLAPQHLN-UHFFFAOYSA-N sodium aluminosilicate Chemical compound [Na+].[Al+3].[O-][Si]([O-])=O.[O-][Si]([O-])=O URGAHOPLAPQHLN-UHFFFAOYSA-N 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 239000012209 synthetic fiber Substances 0.000 description 1
- 229920002994 synthetic fiber Polymers 0.000 description 1
- 238000005292 vacuum distillation Methods 0.000 description 1
Classifications
-
- 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
Abstract
The invention discloses a method for separating dimethyl sulfoxide from wastewater in the synthesis process of ether azole drugs, which comprises the step of carrying out reduced pressure distillation on the wastewater containing the dimethyl sulfoxide and an entrainer to obtain overhead fraction and recovered dimethyl sulfoxide. The invention has the advantages of simple process, convenient operation, low production cost, safety and environmental protection.
Description
Technical Field
The invention relates to the technical field of ether azole medicaments, in particular to a method for separating dimethyl sulfoxide from wastewater in the synthesis process of ether azole medicaments.
Background
Dimethyl sulfoxide (DMSO) is a very important aprotic polar solvent that is soluble in both water and organic solvents. It is called "universal solvent" because of its special solvent effect on chemical reactions and its solubility characteristics for many substances. At present, the method has wide application in many chemical fields such as petroleum, chemical industry, medicine, electronics, synthetic fiber, plastics, printing and dyeing and the like. At present, dimethyl sulfoxide (DMSO) used as a solvent in the synthetic process of an ether azole drug is generally removed by washing, but a large amount of wastewater is generated in the washing process, about one ton of wastewater is generated in the synthetic process of one ton of ether azole drug, 40-50% of dimethyl sulfoxide is contained in the wastewater, the COD content is high, and the dimethyl sulfoxide cannot be treated as conventional wastewater. Therefore, the dimethyl sulfoxide recovery has economic benefit and environmental protection benefit.
Currently, an industrial separation method for recycling DMSO from wastewater containing DMSO is to realize separation of dimethyl sulfoxide and water by simple vacuum distillation. However, the separation method cannot reduce the water content in the DMSO to less than 0.1%, further water removal is required by molecular sieve drying, and the separation method has high distillation temperature, and the DMSO contains a hydrogen-sulfur double bond structure, so that decomposition reaction is easy to occur, the production cost is high, and effective separation cannot be realized. In some high-precision technology fields (such as aerospace field, medical biotechnology field, etc.), the reagent purity has a large influence on the process, so that a reagent with higher purity is generally required. Therefore, there is a need to develop a new method for purifying DMSO efficiently
For example, CN106674066A discloses a method for purifying dimethyl sulfoxide. The purification method comprises the following steps: (1) deacidifying and dewatering; (2) carrying out reduced pressure distillation; (3) carrying out first melting crystallization; (4) and (4) carrying out second melting crystallization. The purification method has low requirements on production equipment and is easy to industrialize; compared with the conventional method, the dimethyl sulfoxide purified product obtained by the purification method has high purity (more than or equal to 99.99 percent) and yield of about 70 percent. Has the disadvantages of complex process, multiple steps, complex operation and high cost.
CN104119256A discloses a method for purifying dimethyl sulfoxide, which comprises feeding raw material containing dimethyl sulfoxide into a first evaporator, heating, partially evaporating, separating vapor and liquid, and feeding the obtained vapor into a rectifying tower; inputting the obtained liquid phase into a second evaporator for heating, performing vapor-liquid separation after partial evaporation, inputting the obtained vapor phase into a rectifying tower, and inputting the obtained liquid phase into a wiped film evaporator; collecting a dimethyl sulfoxide crude product at the tower bottom of the rectifying tower, inputting the dimethyl sulfoxide crude product into a third evaporator for heating, carrying out vapor-liquid separation after partial evaporation, inputting the obtained liquid phase into a wiped film evaporator, and returning the obtained vapor phase to the rectifying tower as a feed; and heating the third evaporator, partially evaporating, separating vapor from liquid, and returning the vapor phase obtained by vapor-liquid separation to the first evaporator as a heating medium, and condensing to obtain purified dimethyl sulfoxide. The disadvantages of the method are that the purification is realized by specific equipment, the equipment investment is large, the cost is high, and the popularization and the application of the method are limited to a certain extent.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides the method for separating the dimethyl sulfoxide from the wastewater in the synthesis process of the ether azole drugs, which has the advantages of simple process, convenient operation, low production cost, safety and environmental protection.
In order to solve the technical problems, the invention adopts the technical scheme that: a method for separating dimethyl sulfoxide from waste water in the process of synthesizing ether azole drugs is characterized in that waste water containing dimethyl sulfoxide and an entrainer are subjected to reduced pressure distillation to obtain a tower top fraction and recovered dimethyl sulfoxide.
In a preferred embodiment of the present invention, the temperature of the reduced pressure distillation is 80 to 120 ℃ and the pressure is
In a preferred embodiment of the present invention, the mass ratio of the azeotropic agent to the wastewater containing dimethyl sulfoxide is 1:5 to 20.
As a preferred embodiment of the present invention, the entrainer is toluene.
In a preferred embodiment of the present invention, the content of dimethyl sulfoxide in the wastewater containing dimethyl sulfoxide is 40 to 50 wt% (wt%, mass percentage content).
In a preferred embodiment of the present invention, the overhead fraction is separated into an upper organic phase and a lower inorganic phase, the upper organic phase is an azeotropic agent and the lower inorganic phase is water, and the upper organic phase can be recycled.
According to the method for separating dimethyl sulfoxide from wastewater in the synthesis process of the ether azole drugs, the entrainer is added for azeotropic distillation, water is entrained by the entrainer through azeotropy of the water and the entrainer, the entrainer is low in price and can be recycled, and the cost is saved; the whole operation process is simple, safe and stable, the content of dimethyl sulfoxide (DMSO) obtained by decompression separation is more than 98.0 wt%, and the water content can be reduced to be less than 0.1 wt%. The separation method has the advantages of simple process, good separation effect, easily obtained raw materials, low cost, safety, environmental protection and the like.
The method for separating dimethyl sulfoxide from wastewater in the synthesis process of ether azole drugs can be operated by adopting a conventional azeotropic distillation tower in the field, and can adopt a continuous or intermittent production mode according to the actual production situation. If a continuous production mode is adopted, the entrainer obtained by layering can flow back to the azeotropic distillation tower.
Compared with the prior art, the invention has the following advantages:
1. the method has the advantages that the process is simple, the cost is low, the entrainer is added for azeotropic distillation, water is entrained by the azeotropic agent and water, the process is obviously simplified, the conventional azeotropic distillation tower in the field can be adopted for operation, the entrainer is cheap and can be recycled, and the production cost is effectively reduced;
2. the method is economic and environment-friendly, the dimethyl sulfoxide is recycled by adding the entrainer for azeotropic distillation, waste is turned into wealth, the entrainer can be recycled, the three-waste emission is obviously reduced, the atom economy is realized, and the requirement of environmental protection is met;
3. the efficiency is high, the purity of the dimethyl sulfoxide (DMSO) obtained after separation is more than 98.5 wt%, the water content can be reduced to be less than 0.1 wt%, and the dimethyl sulfoxide (DMSO) can be recycled and used in the synthesis process of the ether azole drugs.
Detailed Description
The present invention will be described in further detail with reference to examples, but the present invention is not limited to the examples.
The chromatographic operating conditions in the examples were:
analysis was performed by GC2014 type gas chromatograph equipped with FID detector, 60m by 0.32mm by 1 μm SPB-5 quartz capillary column, temperature programmed/deg.c,
detector temperature: 300 ℃, gasification chamber temperature: 260 ℃, sample size: 0.2. mu.L
The liquid substance water content analysis adopts a national standard determination method of Karl Fischer coulometry.
Example 1
165kg of wastewater containing 40 wt% of dimethyl sulfoxide (DMSO) and 8.3kg of entrainer toluene are added into a 300L stainless steel rectifying tower with a rectifying tower section, a delayer, a stirrer and a thermometer, the rectifying tower is sealed, the stirring is started, the rotating speed is 500rpm, the temperature is increased to 85 ℃, the pressure of a system is adjusted to be-0.03 MPa for reduced pressure distillation, the extracted fractions are layered in the delayer, the entrainer obtained at the upper layer can be recycled, the water obtained at the lower layer is separately treated, the reduced pressure distillation is finished after 2 hours, 61.8kg of colorless transparent liquid is obtained at the tower bottom, and the sampling gas chromatography detects that the content of the dimethyl sulfoxide (DMSO) is 98.5%, the moisture content is 0.09%, and the yield is 93.6.0%.
Example 2
165kg of wastewater containing 45 wt% of dimethyl sulfoxide (DMSO) and 16.5kg of entrainer toluene are added into a 300L stainless steel rectifying tower with a rectifying tower section, a delayer, a stirrer and a thermometer, the rectifying tower is sealed, the stirring is started, the rotating speed is 600rpm, the temperature is raised to 95 ℃, the pressure of a system is adjusted to be-0.05 MPa for reduced pressure distillation, the extracted fractions are layered in the delayer, the entrainer obtained at the upper layer can be recycled, the water obtained at the lower layer is separately treated, the reduced pressure distillation is finished after 1.8 hours, 66.0kg of colorless transparent liquid is obtained at the tower bottom, and the sampling gas chromatography detects that the content of the dimethyl sulfoxide (DMSO) is 98.5%, the water content is 0.08% and the yield is 88.9%.
Example 3
165kg of wastewater containing 47 wt% of dimethyl sulfoxide (DMSO) and 24.8kg of entrainer toluene were added to a 300L stainless steel rectifying tower provided with a rectifying tower section, a delayer, a stirrer and a thermometer, and the rectifying tower was sealed. Stirring is started, the rotating speed is 800rpm, the temperature is increased to 105 ℃, the pressure of a system is adjusted to be-0.07 MPa, reduced pressure distillation is carried out, the extracted fraction is layered in a delayer, the entrainer obtained at the upper layer can be recycled, the water obtained at the lower layer is separately treated, the reduced pressure distillation is finished after 1.5 hours, 71.7kg of colorless transparent liquid is obtained at the bottom of the tower, and the content of dimethyl sulfoxide (DMSO) is 98.5 percent, the content of water is 0.07 percent and the yield is 92.5 percent through sampling gas chromatography detection.
Example 4
165kg of wastewater containing 50 wt% of dimethyl sulfoxide (DMSO) and 33.0kg of entrainer toluene were added to a 300L stainless steel rectifying tower provided with a rectifying tower section, a delayer, a stirrer and a thermometer, and the rectifying tower was sealed. Stirring is started, the rotating speed is 300rpm, the temperature is increased to 120 ℃, the pressure of a system is adjusted to-0.09 MPa for reduced pressure distillation, the extracted fraction is layered in a delayer, the entrainer obtained at the upper layer can be recycled, the water obtained at the lower layer is separately treated, the reduced pressure distillation is finished after 1 hour, 78.8kg of colorless transparent liquid is obtained at the bottom of the tower, and the content of dimethyl sulfoxide (DMSO) is 98.5 percent, the content of water is 0.07 percent and the yield is 95.5 percent through the detection of a sampling gas chromatography.
Claims (6)
1. A method for separating dimethyl sulfoxide from waste water in the process of synthesizing ether azole drugs is characterized in that the waste water containing dimethyl sulfoxide and an entrainer are subjected to reduced pressure distillation to obtain overhead fraction and recovered dimethyl sulfoxide.
2. The method for separating dimethyl sulfoxide from wastewater generated in the synthesis process of ether azole drugs according to claim 1, wherein the temperature of reduced pressure distillation is 80-120 ℃, and the pressure is
3. The method for separating dimethyl sulfoxide from wastewater generated in the synthesis process of ether azole drugs according to claim 1, wherein the mass ratio of the entrainer to the wastewater containing dimethyl sulfoxide is 1: 5-20.
4. The method for separating dimethyl sulfoxide from wastewater generated in the synthesis process of ether azole drugs according to claim 1, wherein the entrainer is toluene.
5. The method for separating dimethyl sulfoxide from wastewater generated in the synthesis process of ether azole drugs according to claim 1, wherein the mass percentage of dimethyl sulfoxide in the wastewater containing dimethyl sulfoxide is 40-50%.
6. The method for separating dimethyl sulfoxide from wastewater generated in the synthesis process of ether azole drugs according to claim 1, wherein the overhead fraction is subjected to layering to obtain an upper organic phase and a lower inorganic phase, and the upper organic phase is recycled.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011108552.6A CN112321468A (en) | 2020-10-16 | 2020-10-16 | Method for separating dimethyl sulfoxide from wastewater generated in synthesis process of ether azole drugs |
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| CN202011108552.6A CN112321468A (en) | 2020-10-16 | 2020-10-16 | Method for separating dimethyl sulfoxide from wastewater generated in synthesis process of ether azole drugs |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113607869A (en) * | 2021-07-14 | 2021-11-05 | 北京赛升药业股份有限公司 | Method for detecting residual solvent in antipeger peptide by using gas chromatography and application |
| CN116332813A (en) * | 2022-06-25 | 2023-06-27 | 四川熔增环保科技有限公司 | Recycling method of dimethyl sulfoxide waste solvent |
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| JPH0912534A (en) * | 1995-06-23 | 1997-01-14 | Toray Fine Chem Co Ltd | Recovery of dmso |
| US6414194B1 (en) * | 1999-04-23 | 2002-07-02 | Gaylord Chemical Corporation | Process and apparatus for making ultra-pure DMSO |
| CN103864598A (en) * | 2014-03-20 | 2014-06-18 | 盐城师范学院 | Method for recovering acetic acid and dimethyl sulfoxide from dithianon producing mother liquid |
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| US20160083340A1 (en) * | 2013-04-30 | 2016-03-24 | Toray Fine Chemicals Co., Ltd. | Method of purifying dimethyl sulfoxide |
| CN108129317A (en) * | 2018-01-29 | 2018-06-08 | 淄博高新技术产业开发区精细化工和高分子材料研究院 | A kind of method for continuously recycling PGMEA from PGMEA/ aqueous solutions using azeotropic distillation |
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-
2020
- 2020-10-16 CN CN202011108552.6A patent/CN112321468A/en active Pending
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113607869A (en) * | 2021-07-14 | 2021-11-05 | 北京赛升药业股份有限公司 | Method for detecting residual solvent in antipeger peptide by using gas chromatography and application |
| CN116332813A (en) * | 2022-06-25 | 2023-06-27 | 四川熔增环保科技有限公司 | Recycling method of dimethyl sulfoxide waste solvent |
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