CN111620842A - Method for separating tetrahydrofuran-ethanol-water ternary azeotropic system by reactive distillation and extractive distillation - Google Patents
Method for separating tetrahydrofuran-ethanol-water ternary azeotropic system by reactive distillation and extractive distillation Download PDFInfo
- Publication number
- CN111620842A CN111620842A CN201911069550.8A CN201911069550A CN111620842A CN 111620842 A CN111620842 A CN 111620842A CN 201911069550 A CN201911069550 A CN 201911069550A CN 111620842 A CN111620842 A CN 111620842A
- Authority
- CN
- China
- Prior art keywords
- ethanol
- tetrahydrofuran
- tower
- water
- extractive distillation
- 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.)
- Pending
Links
- 238000000895 extractive distillation Methods 0.000 title claims abstract description 38
- 238000000066 reactive distillation Methods 0.000 title claims abstract description 25
- 238000000034 method Methods 0.000 title claims abstract description 23
- NNCLVCFOZHJMDL-UHFFFAOYSA-N 2-(oxolan-2-yl)ethanol;hydrate Chemical compound O.OCCC1CCCO1 NNCLVCFOZHJMDL-UHFFFAOYSA-N 0.000 title description 5
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 170
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 claims abstract description 152
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 claims abstract description 76
- IAZDPXIOMUYVGZ-UHFFFAOYSA-N Dimethylsulphoxide Chemical compound CS(C)=O IAZDPXIOMUYVGZ-UHFFFAOYSA-N 0.000 claims abstract description 72
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 39
- 239000011259 mixed solution Substances 0.000 claims abstract description 30
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 claims abstract description 23
- 238000011084 recovery Methods 0.000 claims abstract description 22
- 239000002904 solvent Substances 0.000 claims abstract description 22
- 239000000376 reactant Substances 0.000 claims abstract description 16
- 238000000605 extraction Methods 0.000 claims abstract description 15
- IAYPIBMASNFSPL-UHFFFAOYSA-N Ethylene oxide Chemical compound C1CO1 IAYPIBMASNFSPL-UHFFFAOYSA-N 0.000 claims abstract description 8
- 239000000203 mixture Substances 0.000 claims abstract description 7
- 239000006227 byproduct Substances 0.000 claims abstract description 5
- 238000006243 chemical reaction Methods 0.000 claims description 33
- 238000010992 reflux Methods 0.000 claims description 27
- 239000007788 liquid Substances 0.000 claims description 22
- 239000003795 chemical substances by application Substances 0.000 claims description 10
- 238000009833 condensation Methods 0.000 claims description 2
- 230000005494 condensation Effects 0.000 claims description 2
- 239000000047 product Substances 0.000 abstract description 10
- 238000000926 separation method Methods 0.000 abstract description 7
- 238000005265 energy consumption Methods 0.000 abstract description 5
- 238000001816 cooling Methods 0.000 abstract 1
- 238000002156 mixing Methods 0.000 abstract 1
- 238000004064 recycling Methods 0.000 abstract 1
- 239000011555 saturated liquid Substances 0.000 description 9
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 6
- 239000000126 substance Substances 0.000 description 6
- 239000000243 solution Substances 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- HEDRZPFGACZZDS-UHFFFAOYSA-N Chloroform Chemical compound ClC(Cl)Cl HEDRZPFGACZZDS-UHFFFAOYSA-N 0.000 description 2
- 229910002092 carbon dioxide Inorganic materials 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 238000000746 purification Methods 0.000 description 2
- 238000012271 agricultural production Methods 0.000 description 1
- 230000003444 anaesthetic effect Effects 0.000 description 1
- 239000000010 aprotic solvent Substances 0.000 description 1
- 235000013361 beverage Nutrition 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 235000009508 confectionery Nutrition 0.000 description 1
- 150000004292 cyclic ethers Chemical class 0.000 description 1
- 230000007123 defense Effects 0.000 description 1
- 239000000645 desinfectant Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 239000002360 explosive Substances 0.000 description 1
- 235000013305 food Nutrition 0.000 description 1
- 239000003205 fragrance Substances 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 230000007794 irritation Effects 0.000 description 1
- 231100000053 low toxicity Toxicity 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 239000002243 precursor Substances 0.000 description 1
- 235000019633 pungent taste Nutrition 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 235000019654 spicy taste Nutrition 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D307/00—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom
- C07D307/02—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings
- C07D307/04—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having no double bonds between ring members or between ring members and non-ring members
- C07D307/06—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having no double bonds between ring members or between ring members and non-ring members with only hydrogen atoms or radicals containing only hydrogen and carbon atoms, directly attached to ring carbon atoms
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/74—Separation; Purification; Use of additives, e.g. for stabilisation
- C07C29/76—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment
- C07C29/80—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment by distillation
- C07C29/84—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment by distillation by extractive distillation
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/10—Process efficiency
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)
Abstract
The invention discloses a method for separating tetrahydrofuran, ethanol and water of a ternary azeotropic system by combining reactive distillation and extractive distillation, which comprises the steps of adopting ethylene oxide as a reactant and water in a ternary azeotropic mixture to react in a reactive distillation tower C1 to generate a byproduct of ethylene glycol, adopting DMSO as an extractant in a residual tetrahydrofuran and ethanol binary azeotropic system to perform extraction in an extractive distillation tower C2, obtaining a high-purity tetrahydrofuran product at the top of the tower, sending a mixed solution of ethanol and DMSO at the bottom of the tower into the middle part of a solvent recovery tower C3, obtaining a high-purity ethanol product at the top of the solvent recovery tower, obtaining a high-purity extractant DMSO at the bottom of the tower, cooling the high-purity extractant DMSO by a condenser, mixing the high-purity extractant DMSO with a supplemented extractant DMSO, and sending the mixture into the upper part of the extractive distillation tower for recycling, and reducing the dosage. The invention is realized byThe method of rectification combined with extractive rectification solves the separation problem of the ternary multi-azeotropic system of tetrahydrofuran, ethanol and water, thereby effectively solving the problems of high energy consumption and CO consumption of the traditional pressure swing rectification2Row enlargement and the like.
Description
Technical Field
The invention relates to a method for separating a tetrahydrofuran-ethanol-water ternary azeotropic system by combining reaction and rectification with extractive rectification, belonging to the field of rectification and purification.
Background
Tetrahydrofuran and ethanol are both important chemical raw materials. Tetrahydrofuran is a colorless, water-miscible, organic liquid that is less viscous at normal temperature and pressure. The chemical formula of such cyclic ethers can be written as (CH)2)4And O. It is a commonly used medium polarity aprotic solvent due to its long liquid range. Its main use is as a precursor of high molecular polymerAnd (3) a body. Although tetrahydrofuran has a smell and chemical properties similar to diethyl ether, the anesthetic effect is poor. The ethanol is a flammable and volatile colorless transparent liquid at normal temperature and normal pressure, has low toxicity, and can not be directly drunk as a pure liquid; has special fragrance and slight irritation; slightly sweet and accompanied by pungent and spicy taste. Inflammable, its vapor can form explosive mixture with air, and it can be dissolved in water in any ratio. Can be mixed with chloroform, diethyl ether, methanol, acetone and other organic solvents, and has a relative density of 0.816. The ethanol has wide application range, and can be used for preparing acetic acid, beverages, essence, dye, fuel and the like. In medical treatment, ethanol with the volume fraction of 70-75% is also commonly used as a disinfectant and the like, and has wide application in national defense chemical industry, medical treatment and health, food industry, industrial and agricultural production.
In the actual production process of chemical industry and pharmaceutical industry, a mixed solution of tetrahydrofuran, ethanol and water is often formed. In order to reduce production cost and environmental pollution, it is necessary to recycle it. Under normal pressure, tetrahydrofuran, ethanol and water can form a plurality of azeotropes, and the tetrahydrofuran, the ethanol and the water cannot be separated by adopting common rectification and are difficult to separate. And the traditional rectification has high energy consumption, low energy utilization rate and large carbon dioxide emission, so special rectification is required. How to separate the mixed solution of tetrahydrofuran, ethanol and water becomes a problem which needs to be solved urgently.
Disclosure of Invention
In order to solve the technical problems, the invention aims to provide a method for separating a tetrahydrofuran-ethanol-water ternary azeotropic system by combining reaction rectification and extractive rectification, which has the advantages of low energy consumption, high product purity and high environmental protection.
In order to achieve the first object, the technical scheme of the invention is as follows: a method for separating a tetrahydrofuran-ethanol-water ternary azeotropic system by combining reactive distillation and extractive distillation is characterized by comprising the following steps: the water component in the ternary mixture is firstly added with ethylene oxide and water to react in a reaction rectifying tower C1 to remove water, a byproduct ethylene glycol generated after the reaction is extracted from the bottom of the reaction rectifying tower C1, tetrahydrofuran and ethanol steam at the tower top enters a tetrahydrofuran and ethanol condenser to be condensed and then enters a tetrahydrofuran and ethanol reflux tank, one part of the tetrahydrofuran and ethanol steam flows back to the upper part in the reaction rectifying tower C1, and the other part of the tetrahydrofuran and ethanol steam is directly extracted;
taking dimethyl sulfoxide as an extractant, extracting a mixed solution of tetrahydrofuran and ethanol to be separated from the upper part of a reactive distillation column C1, introducing the mixed solution into the middle-lower part of an extractive distillation column C2, and performing countercurrent contact with the extractant introduced from an upper extractant inlet to perform extraction;
extracting tetrahydrofuran from the top of the extractive distillation column C2, condensing the tetrahydrofuran by a tetrahydrofuran condenser, then feeding the tetrahydrofuran into a tetrahydrofuran reflux tank, refluxing part of tetrahydrofuran from the upper part of the extractive distillation column C2 into the extractive distillation column C2 to form gas-liquid mass transfer and heat transfer, and extracting the other part of tetrahydrofuran;
the mixed solution of ethanol and dimethyl sulfoxide extracted from a liquid extraction outlet at the bottom of the extractive distillation column C2 enters the middle part of a solvent recovery column C3, the ethanol and the dimethyl sulfoxide are separated and purified in the solvent recovery column C3, ethanol vapor enters an ethanol condenser for condensation and then enters an ethanol reflux tank, part of ethanol reflows to the upper part of the solvent recovery column C3 to form gas-liquid mass transfer and heat transfer, and the other part of ethanol is extracted;
according to the invention, the water component in the ternary azeotropic mixture is removed by utilizing the efficient reaction of ethylene oxide and water, the azeotropic characteristic can be broken by adding a certain amount of dimethyl sulfoxide (DMSO), which is an extracting agent, to different molecular acting forces of tetrahydrofuran and water, and the separation and purification of a complex ternary azeotropic system are realized by adopting reactive distillation and extractive distillation. The method can effectively reduce the heat load, ensure the product quality, and reduce the production cost and the emission of CO 2. The purity of the separated tetrahydrofuran product is more than 99.5 percent, the purity of the ethanol is more than 99.5 percent, the purity of the by-product glycol is more than 99.9 percent, and the purity of the circulating extractant DMSO is more than 99.99 percent.
In the scheme, the method comprises the following steps: the feeding molar ratio of the reactant to the mixed liquid of tetrahydrofuran, ethanol and water is 1.1-1; the feeding molar ratio of the extracting agent to the mixed liquid of tetrahydrofuran, ethanol and water is 1.1-1.
As a preferable aspect of the above-described aspect: the theoretical plate number of the reaction rectifying tower C1 is 27, the reactant inlet is positioned at 4-6 plates, the inlet of the mixed solution of tetrahydrofuran, ethanol and water is positioned at 8-12 plates, the upper part of the reaction section is positioned at 2-3 plates, the lower part of the reaction section is positioned at 14-16 plates, the tower top temperature is 67-68 ℃, the tower bottom temperature is 201-. The theoretical plate of the extraction rectifying tower C2 is 28, the inlet of the mixed liquid of tetrahydrofuran and ethanol is positioned at 13-15 tower plates, the inlet of the extracting agent is positioned at 3-5 tower plates, the temperature of the tower top is 65-66 ℃, and the temperature of the tower bottom is 125-126 ℃. The theoretical plate of the solvent recovery tower C3 is 25, the inlet of the mixed solution of ethanol and DMSO is positioned at 8-12 tower plates, the temperature of the top of the tower is 77-79 ℃, and the temperature of the bottom of the tower is 196-197 ℃.
In the scheme, the method comprises the following steps: the feeding temperature of the mixed solution of tetrahydrofuran, ethanol and water is 40-60 ℃; the feed temperature of the reactant ethylene oxide is 30-35 ℃.
In the scheme, the method comprises the following steps: the feed flow of the extractant is 60-70 kmol/h.
In the scheme, the method comprises the following steps: the reactant feeding flow of the reactive distillation column C1 is 30-50 kmol/h; the feeding flow of the mixed liquid of tetrahydrofuran, ethanol and water is 90-110 kmol/h.
In the scheme, the method comprises the following steps: the operating pressure of the rectification columns C1, C2 and C3 is normal pressure.
The reflux ratio of the reactive distillation column C1 is 0.7-1.2, the reflux ratio of the extractive distillation column C2 is 0.2-0.8, and the reflux ratio of the solvent recovery column C3 is 0.1-0.5.
Advantageous effects
Compared with the prior art, the invention mainly has the following gain effects:
(1) the separation method of the invention has reasonable operation, strong practicability and extremely high industrial popularization. The reaction rectifying tower and the extraction rectifying tower related by the invention can effectively reduce the separation difficulty, and the obtained product has high purity.
(2) The energy consumption of the separation process is reduced. Compared with the three-tower pressure swing rectification, the reactive rectification combined extraction rectification device related by the invention can reduce the energy consumption cost by 60-80%.
(3) The process can effectively reduce CO2Thereby realizing sustainable green developmentAnd (5) a concept.
Drawings
FIG. 1 is a process flow diagram of the present invention.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
The invention is further illustrated by the following examples:
the foregoing is a more detailed description of the invention, taken in conjunction with specific preferred embodiments thereof.
As shown in fig. 1
The reaction rectifying tower C1 comprises a rectifying section, a reaction section and a stripping section from top to bottom in sequence, the theoretical plate number of the reaction rectifying tower C1 is 27, a reactant inlet a is positioned at 4-6 tower plates, a mixed liquid inlet b is positioned at 8-12 tower plates, the upper part C of the reaction section is positioned at 2-3 tower plates, and the lower part d of the reaction section is positioned at 14-16 tower plates; the mixed solution of tetrahydrofuran and ethanol extracted from the top of the reactive distillation column C1 is sent to the middle lower part of the extractive distillation column C2, the inlet f of the mixed solution of tetrahydrofuran and ethanol is positioned at 12-16 tower plates, and the inlet e of the extractant is positioned at 3-5 tower plates; the mixed solution of ethanol and DMSO extracted from the bottom of the extraction and rectification tower C2 is sent to the middle part of a solvent recovery tower C3, and an inlet g of the mixed solution of ethanol and DMSO is positioned at 8-12 tower plates.
Example 1
The mixed solution of a certain chemical pharmaceutical enterprise comprises the following components after separation: 30% tetrahydrofuran, 30% ethanol, and 40% water.
The operating parameters of the reactive distillation column C1 are as follows: the operation pressure is normal pressure, the number of theoretical plates is 27, a reactant inlet a is positioned at the 5 th tower plate, a mixed liquid inlet b of tetrahydrofuran, ethanol and water is positioned at the 10 th tower plate, the upper part c of the reaction section is positioned at the 2 nd tower plate, the lower part d of the reaction section is positioned at the 15 th tower plate, the reflux ratio is 0.821, and the liquid holdup of the tower plates between the reaction sections c and d is 0.09m3The temperature at the top of the column was 67.7 ℃, the temperature at the bottom of the column was 201.4 ℃, the temperature of the mixture of tetrahydrofuran, ethanol and water was 50 ℃, the flow rate was 100kmol/h, the pressure was 1.2bar (absolute), the temperature of the reactant ethylene oxide was 35 ℃ and the flow rate was 34 kmol/h.
Tetrahydrofuran and ethanol are extracted from the top of the reactive distillation column C1, condensed by a condenser 1 and then enter a reflux tank 2, part of the tetrahydrofuran and ethanol reflux from the upper part of the reactive distillation column C1, and the other part of the tetrahydrofuran and ethanol are extracted.
The operating parameters of the extractive distillation column C2 are as follows: the operation pressure is normal pressure, the number of theoretical plates is 28, the inlet f of the mixed solution of tetrahydrofuran and ethanol is positioned on the 14 th tower plate, the inlet e of the extracting agent is positioned on the 4 th tower plate, the reflux ratio is 0.441, the feeding dimension of the extracting agent is 50 ℃, the flow rate is 66.6mol/h, the temperature of the top of the tower is 65.6 ℃, and the temperature of the bottom of the tower is 125.0 ℃.
The mixed solution of ethanol and DMSO is extracted from the bottom of the extractive distillation column C2, tetrahydrofuran is extracted from the top of the extractive distillation column C2, condensed by a condenser 3 and then enters a reflux tank 4, part of tetrahydrofuran is refluxed from the upper part of the extractive distillation column C2, and the other part of tetrahydrofuran is extracted as a product.
The operating parameters of the solvent recovery column C3 are as follows: the operation pressure is normal pressure, the number of theoretical plates is 25, the inlet g of the mixed solution of ethanol and DMSO is positioned at the 10 th tower plate, the reflux ratio is 0.228, the temperature at the top of the tower is 77.9 ℃, and the temperature at the bottom of the tower is 196.4 ℃.
Ethanol is extracted from the top of the solvent recovery column C3, condensed by a condenser 5 and then enters a reflux tank 6, part of ethanol is refluxed from the upper part of the solvent recovery column C3, and the other part of ethanol is extracted as a product.
And a by-product ethylene glycol saturated liquid extracted from the lower part of the reactive rectification tower C1 flows into the reboiler 7, after being heated by the reboiler 7, one part of the ethylene glycol saturated liquid flows back to the bottom of the reactive rectification tower C1, and the other part of the ethylene glycol saturated liquid is extracted as a product.
The saturated liquid of the mixed solution of ethanol and DMSO extracted from the lower portion of the extractive distillation column C2 flows into the reboiler 8, and after being heated by the reboiler 8, a part of the saturated liquid flows back to the bottom of the extractive distillation column C2, and the other part of the saturated liquid flows to the middle portion of the solvent recovery column C3.
And the DMSO saturated liquid extracted from the lower part of the solvent recovery tower C3 flows into a reboiler 9, after being heated by the reboiler 9, one part of the DMSO saturated liquid flows back to the bottom of the solvent recovery tower C3, and the other part of the DMSO saturated liquid is sent to the condenser 10, condensed, mixed with the added extractant DMSO and sent to the upper part of the extractive distillation tower C2.
The purity of the ethylene glycol product obtained after separation is more than 99.9%, the purity of tetrahydrofuran is more than 99.5%, the purity of ethanol is more than 99.5%, and the purity of DMSO is more than 99.99%.
Example 2
The rest is the same as in example 1, except that:
the mixed solution of a certain petrochemical enterprise comprises the following components: 35% tetrahydrofuran, 35% ethanol and 30% water.
The temperature of the mixed solution of tetrahydrofuran, ethanol and water is 50 ℃, the flow rate is 100kmol/h, the pressure is 1.2bar (absolute pressure), the temperature of the reactant is 30 ℃, the flow rate is 30kmol/h, the temperature of the extracting agent DMSO is 50 ℃, and the flow rate is 72 kmol/h.
The operating parameters of the reactive distillation column C1 are as follows: theoretical plate number is 30, reactant inlet a is located at 7 th column plate, mixed liquor inlet b is located at 17 th column plate, reaction section upper part c is located at 3 rd column plate, reaction section lower part d is located at 15 th column plate, reflux ratio is 0.905, column plate liquid holdup between reaction sections c-d is 0.10m3The temperature at the top of the column was 67.9 ℃, the temperature at the bottom of the column was 201.2 ℃, the temperature of the reactant ethylene oxide was 30 ℃ and the flow rate was 30 kmol/h.
The operating parameters of the extractive distillation column C2 are as follows: the theoretical plate number is 30, the inlet f of the mixed solution of tetrahydrofuran and ethanol is positioned on the 18 th plate, the inlet e of the extracting agent is positioned on the 5 th plate, the reflux ratio is 0.589, the temperature of the top of the extraction rectifying tower is 73.2 ℃, and the temperature of the bottom of the extraction rectifying tower C1 is 147.1 ℃.
The operating parameters of the solvent recovery column C3 are as follows: the theoretical plate number is 24, the inlet g of ethanol and DMSO is positioned at the 8 th plate, the reflux ratio is 0.368, the temperature at the top of the tower is 78.0 ℃, and the temperature at the bottom of the tower is 196.5 ℃.
Example 3:
the rest is the same as in example 1, except that:
the mixed solution of a certain petrochemical enterprise comprises the following components: 25% tetrahydrofuran, 25% ethanol and 50% water.
The temperature of the mixed solution of tetrahydrofuran, ethanol and water is 50 ℃, the flow rate is 100kmol/h, the pressure is 1.2bar (absolute pressure), the inlet temperature of the reactant is 33 ℃, the flow rate is 50kmol/h, the feeding temperature of the extracting agent DMSO is 50 ℃, and the flow rate is 50 kmol/h.
The operating parameters of the reactive distillation column C1 are as follows: theoretical plate number is 26, reactant inlet a is located at the 4 th tray, mixed liquor inlet b is located at the 16 th tray, upper part c of reaction section is located at the 4 th tray, lower part d of reaction section is located at the 18 th tray, reflux ratio is 1.105, tray liquid holdup between reaction sections c-d is 0.12m3The temperature at the top of the column was 68.0 ℃, the temperature at the bottom of the column was 201.5 ℃, the temperature of the reactant ethylene oxide was 33 ℃ and the flow rate was 50 kmol/h.
The operating parameters of the extractive distillation column C2 are as follows: the theoretical plate number is 27, the inlet f of the mixed solution of tetrahydrofuran and ethanol is positioned on the 15 th plate, the inlet e of the extracting agent is positioned on the 3 rd plate, the reflux ratio is 0.612, the temperature of the top of the extraction rectifying tower is 73.3 ℃, and the temperature of the bottom of the extraction rectifying tower C1 is 147.5 ℃.
The operating parameters of the solvent recovery column C3 are as follows: the theoretical plate number is 27, the inlet g of ethanol and DMSO is positioned at the 9 th plate, the reflux ratio is 0.405, the temperature at the top of the tower is 78.1 ℃, and the temperature at the bottom of the tower is 196.6 ℃.
Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those skilled in the art; the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; these modifications and substitutions do not cause the essence of the corresponding technical solution to depart from the scope of the technical solution of the embodiments of the present invention, and are intended to be covered by the claims and the specification of the present invention.
Claims (8)
1. A method for separating tetrahydrofuran, ethanol and water ternary azeotropic system by combining reactive distillation and extractive distillation is characterized in that: a rectifying section, a reaction section and a stripping section are arranged in the reactive rectifying tower C1 from top to bottom; the extractive distillation column C2 is internally provided with a rectifying section, an extracting section and a stripping section from top to bottom in sequence:
the water component in the ternary mixture is firstly added with ethylene oxide and water to react in a reaction rectifying tower C1 to remove water, a byproduct ethylene glycol generated after the reaction is extracted from the bottom of the reaction rectifying tower C1, tetrahydrofuran and ethanol steam at the tower top enters a tetrahydrofuran and ethanol condenser to be condensed and then enters a tetrahydrofuran and ethanol reflux tank, one part of the tetrahydrofuran and ethanol steam flows back to the upper part in the reaction rectifying tower C1, and the other part of the tetrahydrofuran and ethanol steam is directly extracted;
taking dimethyl sulfoxide as an extractant, extracting a mixed solution of tetrahydrofuran and ethanol to be separated from the upper part of a reactive distillation column C1, introducing the mixed solution into the middle-lower part of an extractive distillation column C2, and performing countercurrent contact with the extractant introduced from an upper extractant inlet to perform extraction;
extracting tetrahydrofuran from the top of the extractive distillation column C2, condensing the tetrahydrofuran by a tetrahydrofuran condenser, then feeding the tetrahydrofuran into a tetrahydrofuran reflux tank, refluxing part of tetrahydrofuran from the upper part of the extractive distillation column C2 into the extractive distillation column C2 to form gas-liquid mass transfer and heat transfer, and extracting the other part of tetrahydrofuran;
the mixed liquid of ethanol and dimethyl sulfoxide extracted from a liquid extraction outlet at the bottom of the extractive distillation column C2 enters the middle part of a solvent recovery column C3, the ethanol and the dimethyl sulfoxide are separated and purified in the solvent recovery column C3, ethanol vapor enters an ethanol condenser for condensation and then enters an ethanol reflux tank, a part of ethanol reflows to the upper part of the solvent recovery column C3 to form gas-liquid mass transfer and heat transfer, and the other part of ethanol is extracted.
2. The method for separating the ternary azeotropic system of tetrahydrofuran, ethanol and water by combining reactive distillation and extractive distillation according to claim 1, which is characterized in that: the feeding molar ratio of reactants to tetrahydrofuran, ethanol and water is 0.3-0.5, and the feeding temperature is 30-35 ℃; the feeding molar ratio of the extracting agent to the mixed solution of tetrahydrofuran and ethanol is 1.2-0.8, and the feeding temperature is 50 ℃.
3. The method for separating the ternary azeotropic system of tetrahydrofuran, ethanol and water by combining reactive distillation and extractive distillation according to claim 1, which is characterized in that: the theoretical plate number of the reaction rectifying tower C1 is 25-30, and the reactant inlet positionAt 3-6 tower plates, mixed liquid inlet at 8-12 tower plates, and liquid holdup between reaction sections of 0.08-0.12m3The tower top temperature is 77-79 ℃, and the tower bottom temperature is 196-197 ℃.
4. The method for separating the ternary azeotropic system of tetrahydrofuran, ethanol and water by combining reactive distillation and extractive distillation according to claim 1, which is characterized in that: the feeding temperature of the mixed solution of tetrahydrofuran, ethanol and water is 40-60 ℃.
5. The method for separating the ternary azeotropic system of tetrahydrofuran, ethanol and water by combining reactive distillation and extractive distillation according to claim 1, which is characterized in that: the number of theoretical plates of the extraction rectifying tower C2 is 25-30, an extractant feeding port is positioned at the 3 rd-6 th tower plate, a tetrahydrofuran and ethanol mixed solution inlet is positioned at the 8 th-12 th tower plate, the feeding temperature of an extractant DMSO is 40-60 ℃, and the flow rate is 50-80 kmol/h.
6. The method for separating the ternary azeotropic system of tetrahydrofuran, ethanol and water by combining reactive distillation and extractive distillation according to claim 1, which is characterized in that: the theoretical plate number of the solvent recovery tower C3 is 23-27, and the inlet of the mixed solution of ethanol and DMSO is positioned at the 7 th-12 th plate.
7. The method for separating the ternary azeotropic system of tetrahydrofuran, ethanol and water by combining reactive distillation and extractive distillation according to claim 1, which is characterized in that: the operating pressure of the reaction rectifying tower C1, the extraction rectifying tower C2 and the solvent recovery tower C3 is normal pressure.
8. The method for separating the ternary azeotropic system of tetrahydrofuran, ethanol and water by combining reactive distillation and extractive distillation according to claim 1, which is characterized in that: the reflux ratio of the reactive distillation column C1 is 0.7-1.2, the reflux ratio of the extractive distillation column C2 is 0.2-0.8, and the reflux ratio of the solvent recovery column C3 is 0.1-0.5.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911069550.8A CN111620842A (en) | 2019-10-28 | 2019-10-28 | Method for separating tetrahydrofuran-ethanol-water ternary azeotropic system by reactive distillation and extractive distillation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911069550.8A CN111620842A (en) | 2019-10-28 | 2019-10-28 | Method for separating tetrahydrofuran-ethanol-water ternary azeotropic system by reactive distillation and extractive distillation |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111620842A true CN111620842A (en) | 2020-09-04 |
Family
ID=72269348
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911069550.8A Pending CN111620842A (en) | 2019-10-28 | 2019-10-28 | Method for separating tetrahydrofuran-ethanol-water ternary azeotropic system by reactive distillation and extractive distillation |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111620842A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111517920A (en) * | 2020-04-21 | 2020-08-11 | 青岛科技大学 | Process for separating tetrahydrofuran-methanol-water by three-tower batch rectification |
| CN113457193A (en) * | 2021-06-25 | 2021-10-01 | 济南大学 | Device and method for separating methanol-methylal-methyl formate mixture |
| CN113975845A (en) * | 2021-11-05 | 2022-01-28 | 南京工业大学 | Extractive distillation device for dehydrating low-concentration acetonitrile solution and control method |
| CN114702368A (en) * | 2022-04-18 | 2022-07-05 | 重庆科技学院 | Method for separating tertiary butanol-ethanol-water ternary azeotropic system by double-tower reactive extraction side-stream rectification process |
| CN114797146A (en) * | 2022-05-12 | 2022-07-29 | 重庆科技学院 | Double-partition extraction rectifying tower |
| CN114939283A (en) * | 2022-05-12 | 2022-08-26 | 重庆科技学院 | Method for separating and purifying ethyl acetate-methanol-water ternary azeotropic mixture |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102875327A (en) * | 2012-10-30 | 2013-01-16 | 中国海洋大学 | Technique for preparing absolute ethanol from near-azeotropic-concentration ethanol-water mixture |
| CN106928164A (en) * | 2017-03-03 | 2017-07-07 | 南京师范大学 | A kind of separation method of tetrahydrofuran ethanol water toluene mixed solution |
| CN106967017A (en) * | 2017-04-10 | 2017-07-21 | 青岛科技大学 | A kind of method of mixed extractant separation of tetrahydrofuran ethanol water mixture |
| CN109678820A (en) * | 2019-01-22 | 2019-04-26 | 青岛科技大学 | A kind of method of complete thermal coupling abstraction distillation separation of tetrahydrofuran-ethyl alcohol-aqueous mixtures |
| CN109734685A (en) * | 2018-12-29 | 2019-05-10 | 青岛科技大学 | A kind of method of part thermal coupling abstraction distillation separation of tetrahydrofuran-ethyl alcohol-aqueous mixtures |
-
2019
- 2019-10-28 CN CN201911069550.8A patent/CN111620842A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102875327A (en) * | 2012-10-30 | 2013-01-16 | 中国海洋大学 | Technique for preparing absolute ethanol from near-azeotropic-concentration ethanol-water mixture |
| CN106928164A (en) * | 2017-03-03 | 2017-07-07 | 南京师范大学 | A kind of separation method of tetrahydrofuran ethanol water toluene mixed solution |
| CN106967017A (en) * | 2017-04-10 | 2017-07-21 | 青岛科技大学 | A kind of method of mixed extractant separation of tetrahydrofuran ethanol water mixture |
| CN109734685A (en) * | 2018-12-29 | 2019-05-10 | 青岛科技大学 | A kind of method of part thermal coupling abstraction distillation separation of tetrahydrofuran-ethyl alcohol-aqueous mixtures |
| CN109678820A (en) * | 2019-01-22 | 2019-04-26 | 青岛科技大学 | A kind of method of complete thermal coupling abstraction distillation separation of tetrahydrofuran-ethyl alcohol-aqueous mixtures |
Non-Patent Citations (2)
| Title |
|---|
| YADOLLAH TAVAN: "Feasibility and parametric study of tetrahydrofuran dehydration using reactive distillation with low energy requirement" * |
| 王金桃，等: "萃取精馏分离四氢呋喃-乙醇共沸物的过程模拟研究" * |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111517920A (en) * | 2020-04-21 | 2020-08-11 | 青岛科技大学 | Process for separating tetrahydrofuran-methanol-water by three-tower batch rectification |
| CN111517920B (en) * | 2020-04-21 | 2022-04-12 | 青岛科技大学 | Process for separating tetrahydrofuran-methanol-water by three-tower batch rectification |
| CN113457193A (en) * | 2021-06-25 | 2021-10-01 | 济南大学 | Device and method for separating methanol-methylal-methyl formate mixture |
| CN113457193B (en) * | 2021-06-25 | 2023-01-17 | 济南大学 | Device and method for separating methanol-methylal-methyl formate mixture |
| CN113975845A (en) * | 2021-11-05 | 2022-01-28 | 南京工业大学 | Extractive distillation device for dehydrating low-concentration acetonitrile solution and control method |
| CN114702368A (en) * | 2022-04-18 | 2022-07-05 | 重庆科技学院 | Method for separating tertiary butanol-ethanol-water ternary azeotropic system by double-tower reactive extraction side-stream rectification process |
| CN114797146A (en) * | 2022-05-12 | 2022-07-29 | 重庆科技学院 | Double-partition extraction rectifying tower |
| CN114939283A (en) * | 2022-05-12 | 2022-08-26 | 重庆科技学院 | Method for separating and purifying ethyl acetate-methanol-water ternary azeotropic mixture |
| CN114797146B (en) * | 2022-05-12 | 2023-07-25 | 重庆科技学院 | Double-baffle extraction rectifying tower for separating ethyl acetate-methanol-water ternary azeotrope |
| CN114939283B (en) * | 2022-05-12 | 2023-11-28 | 重庆科技学院 | Method for separating and purifying ethyl acetate-methanol-water ternary azeotropic mixture |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111620842A (en) | Method for separating tetrahydrofuran-ethanol-water ternary azeotropic system by reactive distillation and extractive distillation | |
| CN106431812B (en) | A kind of method and device of separation of extractive distillation toluene-methanol-water azeotropic mixture | |
| CN101284762B (en) | Method for the production of very pure 1,4-butanediol | |
| CN113214039B (en) | Extractive distillation process for separating ternary complex azeotropic mixture cyclohexane/normal propyl alcohol/water | |
| CN110885283A (en) | Energy-saving process for separating ethyl acetate-ethanol by heat integration extraction rectification with side extraction | |
| CN105111079A (en) | Method and device for separating acetic acid sec-butyl ester and sec-butyl alcohol | |
| CN111100004B (en) | Method and integrated device for refining dimethyl carbonate | |
| CN111072481A (en) | Device and method for producing high-concentration dimethyl carbonate | |
| WO2020015321A1 (en) | Method and device for separating isopropanol | |
| CN111620843A (en) | Method for separating tetrahydrofuran-ethanol-water ternary azeotropic system by combining reactive distillation with side line extractive distillation | |
| CN112010755B (en) | System for purifying crude dimethyl carbonate by pressure-variable double-effect rectification | |
| CN208182888U (en) | Reactive distillation-film device coupling production ethyl acetate in high purity device | |
| CN111170823B (en) | Method for simultaneously extracting phenol and naphthalene from tar | |
| CN105732319B (en) | A kind of method for being thermally integrated transformation batch fractionating separation methanol-acetonitrile azeotropic mixture | |
| CN111377801B (en) | Method and system for refining low carbon alcohol | |
| CN114702368A (en) | Method for separating tertiary butanol-ethanol-water ternary azeotropic system by double-tower reactive extraction side-stream rectification process | |
| CN217187959U (en) | Tetrahydrofuran recycling and refining device | |
| CN116410068A (en) | Method for separating methyl tertiary butyl ether-ethanol-water mixture by extractive distillation | |
| CN114939283A (en) | Method for separating and purifying ethyl acetate-methanol-water ternary azeotropic mixture | |
| CN106187717B (en) | The method for being thermally integrated variable-pressure rectification separation methyl tertiary butyl ether(MTBE) and methanol azeotrope | |
| CN115282913A (en) | Reaction system and method for preparing methyl propionate | |
| CN106966867A (en) | A kind of three tower is thermally integrated variable-pressure rectification separation methanol, ethanol, the energy saving technique of benzene | |
| CN110963892A (en) | Method for separating n-propanol and water by using efficient ionic liquid extraction and rectification | |
| CN111646900A (en) | Separation system and separation method for dimethyl carbonate and methanol | |
| CN111072495A (en) | Method for purifying 2-methyl-1, 2-propane diamine |
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 | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200904 |
|
| RJ01 | Rejection of invention patent application after publication |