CN111269095A - Method and system for refining ethylene glycol tert-butyl ether - Google Patents
Method and system for refining ethylene glycol tert-butyl ether Download PDFInfo
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Abstract
The invention provides a refining method of ethylene glycol tert-butyl ether, which comprises the steps of pumping a material obtained by reacting ethylene glycol with isobutene or mixed C4 out of a reactor, sending the material into a flash distillation tower, sending a material at the bottom of the tower subjected to flash distillation separation into a reduced pressure distillation tower, sending a product mixture distilled from the top of the reduced pressure distillation tower into an azeotropic distillation tower, adding entrainer water, carrying out azeotropic distillation to obtain a product ethylene glycol tert-butyl ether at the bottom of the tower, sending a byproduct mixture of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether and C8 hydrocarbon obtained at the top of the tower into a water washing tower, carrying out water washing to obtain a mixture of ethylene glycol di-tert-butyl ether and C8 hydrocarbon at the top of the tower, and returning the mixture of the ethylene glycol mono. The method greatly reduces the loss of the ethylene glycol mono-tert-butyl ether, and the yield of the main product ethylene glycol mono-tert-butyl ether is higher and reaches more than 99 percent. The method has the advantages of short separation process, low equipment investment and greatly reduced energy consumption.
Description
Technical Field
The invention relates to a method and a system for refining ethylene glycol tert-butyl ether.
Background
The ethylene glycol tert-butyl Ether (ETB) is an isomer of ethylene glycol n-butyl ether, has the physical properties similar to those of ethylene glycol butyl ether, but has the advantages of slightly low boiling point, slightly high evaporation speed, good water solubility, uniform aqueous solution, good storage stability as solvent coating and ink, small skin irritation, and environmental friendliness. The coating is widely applied to water dispersible coatings, and the demand and market rate can be greatly improved.
The glycol ethers are generally prepared by the following methods: 1. reacting sodium ethylene glycol with organic halide, and reacting sodium ethylene glycol with tert-butyl chloride; 2. ethylene oxide and tertiary butyl alcohol are subjected to etherification reaction to obtain corresponding ethylene glycol mono-tertiary butyl ether, a small amount of diethylene glycol ether and triethylene glycol ether; 3. glycol and tert-butyl alcohol generate glycol ethers under the condition that inorganic acid is used as a catalyst, the method has poor selectivity to glycol mono-tert-butyl ether, and simultaneously generates part of water to form waste acid with the catalyst, thereby increasing the problem of environmental protection treatment; 4. the alkene alcohol method adopts saturated alcohol and alkene as raw materials, the alcohol and the alkene are fully contacted under the action of a catalyst, a certain temperature and pressure are kept, and the alcohol and the alkene are subjected to addition reaction to generate corresponding ether. The method belongs to atomic chemistry, is green and environment-friendly, and has low cost, but the method has large equipment investment, high selectivity to reactant alcohols, and large difference of reaction conversion rates of alcohols with different activities and alkenes, and is successfully applied to the production of methyl tert-butyl ether so far.
Chinese patent CN103402958B discloses a process for preparing a glycol mono-t-butyl ether compound, which comprises a catalytic reaction step of reacting a glycol compound with a C4 hydrocarbon mixture containing isobutylene in the presence of an acidic catalyst at a reaction temperature of 30 to 90 ℃ to prepare a glycol mono-t-butyl ether compound and a glycol di-t-butyl ether compound as a by-product; recycling a portion of the reaction mixture of said catalytic reaction step and feeding it to the recycling step of said catalytic reaction step, wherein the amount of recycled reaction mixture is 1-20 times the amount of reaction mixture that is not recycled; a byproduct extraction step of separating the glycol mono-t-butyl ether compound and the glycol di-t-butyl ether compound obtained in the catalytic reaction step using a hydrophilic extractant and a lipophilic extractant; a hydrophilic extractant removing step of separating the hydrophilic extractant from the glycol mono-t-butyl ether compound and recycling the hydrophilic extractant to the byproduct extracting step; separating unreacted C4 hydrocarbon mixture and the lipophilic extractant from the glycol di-tert-butyl ether compound and recycling the unreacted C4 hydrocarbon mixture and the lipophilic extractant to the lipophilic extractant and unreacted C4 hydrocarbon mixture removal step of the byproduct extraction step; and a byproduct decomposition and recycling step of decomposing the separated glycol di-t-butyl ether compound into a glycol compound and isobutylene and recycling them to the catalytic reaction step.
In the invention, a hydrophilic extractant and a lipophilic extractant are introduced in the separation process, the energy consumption in the separation process is high, and simultaneously, the separation process is long.
Chinese patent application CN106397137A discloses a method for preparing dihydric alcohol mono-tertiary butyl ether, wherein gaseous isobutene and liquid dihydric alcohol are respectively introduced into a reaction rectifying tower from the lower part and the upper part of a catalyst bed layer to carry out countercurrent heterogeneous reaction, a gas-phase product enters a rectifying section at the upper part of a reactor, the dihydric alcohol mono-tertiary butyl ether is extracted from the top and the side line of the tower, unreacted isobutene is extracted from the top of the tower in a gas form for recycling, and unreacted dihydric alcohol is extracted from the bottom of the tower for recycling. The invention adopts catalytic distillation reaction, and the catalytic distillation technology has the problems of large investment, complex catalyst replacement and the like.
Production and utilization of foreign ethylene glycol t-butyl ether, Shenjing, Fine petrochemical, 1996, 9 (5): 45-50 discloses a preparation process of Nippon Bolus company, wherein ethylene glycol and isobutene in a naphtha cracking byproduct C4 fraction (mixed C4) are reacted under the action of a strong acid ion exchange resin catalyst, the retention time of reactants is 1h, the feeding temperature of a reactor is 90 ℃, the pressure is 2.0MPa, and the molar ratio of Ethylene Glycol (EG) to Isobutene (IB) is 2.7: 1. The outlet temperature of the reaction product gas is 119 ℃, the pressure is 1.7MPa, some reaction products are recycled to the reactor to inhibit the generation of byproduct ethylene glycol di-tert-butyl ether (DBE), and the recycling amount is set to ensure that the molar ratio of ETB to IB in the raw materials is 1: 1 and the molar ratio of DBE to IB is 0.5: 1. The IB conversion rate is 81 percent, and the ETB selectivity can reach 83 percent.
The separation process is completed by adopting 4 towers, the product after the reaction firstly enters a C4 stripping tower, mixed C4 is separated from the top of the tower, and the material at the bottom of the tower enters an azeotropic tower; in the azeotropic tower, using water as an entrainer, a mixture of ethylene glycol di-tert-butyl ether (DBE) and ethylene glycol mono-tert-butyl Ether (ETB) separated from the top of the azeotropic tower is sent to a DBE tower, and a mixture of ethylene glycol mono-tert-butyl Ether (ETB) and Ethylene Glycol (EG) separated from the bottom of the azeotropic tower is sent to an ETB tower; separating out a mixture of ethylene glycol di-tert-butyl ether (DBE) and ethylene glycol mono-tert-butyl Ether (ETB) at the top of the DBE tower, returning the mixture to the azeotropic tower for re-separation, and separating out ethylene glycol di-tert-butyl ether (DBE) with higher purity at the bottom of the tower, returning the ethylene glycol di-tert-butyl ether (DBE) to the inlet of the reactor as a reaction material; and (3) separating ethylene glycol tert-butyl Ether (ETB) from the top of the ETB tower, and separating Ethylene Glycol (EG) from the bottom of the ETB tower to be recycled to the inlet of the reactor as a reaction material.
However, the process has the problems of large DBE circulation ratio, low selectivity of ethylene glycol mono-tert-butyl ether, more carbon-eight (diisobutylene) by-product generation and high energy consumption.
In addition, the research on the development of the synthesis process of ethylene glycol tert-butyl ether, thanks to kukou, luvingqi, zhu jiu, zhu hui, zhang hui, fine petrochemical, 1997, 5 (3): 19-22, a 150t/a pilot plant is established, mixed C4, ethylene glycol and strong-acid ion exchange resin are used for synthesizing the ETB, the reaction temperature is 40-50 ℃, the reaction pressure is 1.0MPa, the reaction space velocity is 1.6-2.0, the conversion per pass of isobutene reaches 95%, and the selectivity of the ETB is 83-85%.
The technological process is basically the same as that of Nippon Wanshan Co, the first 3 towers in the separation process are a C4 removing tower, an azeotropic tower and an ETB refining tower in sequence, and a mixed C4 is separated from a reaction product in a C4 removing tower; separating out the mixture of DBE with ETB and diisobutylene as a byproduct at the top of the azeotropic tower, and feeding the mixture of ETB and glycol at the bottom of the azeotropic tower into an ETB refining tower; separating out an ETB pure product at the tower top, and feeding the ethylene glycol separated out at the tower bottom into an ethylene glycol single distillation tower; impurities in the recycle ethylene glycol feed (presumably polymer of ethylene glycol) were separated at the bottom and the overhead ethylene glycol was recycled to the reactor inlet as reaction feed.
The process has the problems of low ETB selectivity (83-85%), more byproducts (15-30%) such as DBE (diethylene glycol) and carbon eight (diisobutylene), high energy consumption for refining glycol and low ETB yield.
Chinese patent application CN107434762A discloses a method for preparing and refining ethylene glycol mono-tert-butyl ether, which comprises the steps of adopting ethylene glycol and mixed C4 as initial reaction materials in the presence of an acid catalyst, adding tert-butyl alcohol, mixing, carrying out etherification reaction in a reactor, and then separating and refining to obtain the ethylene glycol mono-tert-butyl ether. The reaction conditions are as follows: the temperature is 10-60 ℃, the pressure is 0.2-1.5 MPa, and the airspeed is 0.1-10.0 h-1. Finally, the ethylene glycol mono-tertiary butyl ether is obtained by separation and refining. The process for separating and refining the ethylene glycol mono-tert-butyl ether comprises the following steps of respectively refining reaction products through 4 rectifying towers T1, T2, T3 and T4: a) at column T1, unreacted mixed C4 is separated overhead and the bottoms feed is fed to column T2; b) in column T2, unreacted ethylene glycol is separated at the bottom, and the overhead material of column T2 enters column T3; c) refined ethylene glycol mono-tert-butyl ether is obtained at the bottom of the tower T3, tert-butyl alcohol and by-products separated from the top of the tower enter a tower T4; d) in column T4, tert-butanol is separated off at the top and mixed ethers are separated off at the bottom.
In the invention, a four-tower separation technology is adopted, but the by-product ethylene glycol tert-butyl ether can not be separated, and the tert-butyl alcohol is added in the reaction, so that the ethylene glycol tert-butyl ether is required to be recycled after separation.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a method for refining ethylene glycol mono-tert-butyl ether, which has low energy consumption, can separate ethylene glycol mono-tert-butyl ether and ethylene glycol di-tert-butyl ether with higher purity, and has shorter separation process and lower equipment investment.
Accordingly, the present invention provides a method for refining ethylene glycol t-butyl ether, comprising: (1) pumping the material obtained after the reaction of ethylene glycol and isobutene or mixed C4 from the reactor, sending the material into a flash tower, carrying out flash separation, evaporating unreacted isobutene or mixed C4 from the top of the tower, and returning the unreacted isobutene or mixed C4 to the reactor (the reactor obtained by the reaction of ethylene glycol and isobutene or mixed C4) for recycling, wherein the mixed material of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether, C8 hydrocarbon (a mixture of C8 hydrocarbon alkane and alkene, mainly alkene), C12 hydrocarbon (a mixture of C12 hydrocarbon alkane and alkene, mainly alkene) and ethylene glycol falls into the bottom of the tower;
(2) feeding the mixed material from the bottom of the flash tower into a vacuum rectification tower, pumping out the mixture of ethylene glycol and C12 hydrocarbon after falling into the bottom of the tower, returning the mixture to the reactor for recycling, and evaporating a product mixture of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether and C8 hydrocarbon from the top of the tower;
(3) feeding the product mixture distilled from the top of the reduced pressure distillation tower into an azeotropic distillation tower, adding entrainer water, performing azeotropic distillation to obtain a product ethylene glycol mono-tert-butyl ether at the bottom of the tower, and obtaining a byproduct mixture of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether and C8 hydrocarbon at the top of the tower;
(4) and (3) feeding the byproduct mixture obtained from the top of the azeotropic distillation tower into a water washing tower, and washing to obtain a mixture of ethylene glycol di-tert-butyl ether and C8 hydrocarbon at the top of the tower, preferably, obtaining a mixture of ethylene glycol mono-tert-butyl ether and water at the bottom of the tower and returning the mixture to the azeotropic distillation tower for recycling.
In the invention, the reaction is carried out by adopting ethylene glycol to react with isobutene or mixed C4, and the mixture after the reaction comprises isobutene or mixed C4, ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether, C8 hydrocarbon, C12 hydrocarbon and ethylene glycol.
Because the reaction can not be completely carried out and the unreacted isobutene and the mixed C4 need to be separated, a flash tower is arranged to separate the unreacted light component (isobutene or mixed C4), and the isobutene or the mixed C4 obtained after separation can be continuously returned to the reaction for recycling and can also be conveyed to a downstream device through a pipeline. The top temperature of the flash tower is 35-70 ℃, preferably 38-65 ℃, more preferably 40-60 ℃, more preferably 40-55 ℃, and further preferably 40-50 ℃; the overhead pressure is 0.3 to 0.6MPa, preferably 0.35 to 0.55MPa, more preferably 0.38 to 0.52MPa, and further preferably 0.40 to 0.50 MPa; the reflux ratio is 1-10: 1, preferably 2 to 8: 1, more preferably 2 to 6: 1, more preferably 2 to 5: 1, more preferably 2 to 4: 1.
in the present invention, the reaction of ethylene glycol cannot be completed because of its excess during the reaction, and a large amount of ethylene glycol still remains in the reaction mixture and needs to be separated. In the invention, the decompression rectifying tower is arranged behind the flash tower to separate the unreacted glycol, and the components are separated in the early stage, thereby avoiding the large energy consumption of the glycol in the subsequent separation step. And returning the separated glycol to the reactor for recycling. In the invention, the top temperature of the vacuum rectification tower is 40-50 ℃, preferably 41-49 ℃, more preferably 42-48 ℃, more preferably 43-47 ℃, and further preferably 44-46 ℃; the pressure at the top of the column is-0.101 MPa to-0.089 MPa, preferably-0.1 MPa to-0.09 MPa, more preferably-0.099 MPa to-0.091 MPa, more preferably-0.098 MPa to-0.092 MPa, more preferably-0.097 MPa to-0.093 MPa, and further preferably-0.096 MPa to-0.094 MPa; the reflux ratio is 1-10: 1, preferably 2 to 9: 1, more preferably 2 to 8: 1, more preferably 2 to 7: 1, more preferably 2 to 6: 1, more preferably 2 to 5: 1, more preferably 2 to 4: 1, more preferably 2 to 3: 1.
in the invention, the reacted mixture is separated by a flash tower and a reduced pressure rectifying tower to obtain a product mixture of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether and C8 hydrocarbon, wherein the boiling point of the ethylene glycol mono-tert-butyl ether is 152 ℃, the boiling point of the ethylene glycol di-tert-butyl ether is 170 ℃, the ordinary rectification is adopted, the boiling points of the ethylene glycol mono-tert-butyl ether and the ethylene glycol di-tert-butyl ether are high, the energy consumption is high, meanwhile, the azeotropic boiling point of the ethylene glycol mono-tert-butyl ether and the ethylene glycol di-tert-butyl ether is. Therefore, the two components cannot be effectively separated by ordinary rectification, and other separation methods are necessary. Experiments show that the two components can be effectively separated by adopting water-adding azeotropic distillation, the azeotropic point is lower, the steam can be saved to a great extent, and the energy consumption is reduced. Experiments show that the ternary azeotropic temperature of water, ethylene glycol mono-tert-butyl ether and ethylene glycol di-tert-butyl ether is 99.4 ℃, and the azeotropic temperature of water and ethylene glycol mono-tert-butyl ether is 100.6 ℃. The ternary azeotropic composition of water, ethylene glycol mono-tert-butyl ether and ethylene glycol di-tert-butyl ether is as follows: 54.45 percent of water, 14.75 percent of ethylene glycol mono-tert-butyl ether and 30.80 percent of ethylene glycol di-tert-butyl ether. The binary azeotropic composition of water and ethylene glycol mono-tert-butyl ether comprises 64.12% of water and 35.88% of ethylene glycol mono-tert-butyl ether. In the present invention, water and C8 olefins can also form azeotropes whose average mass composition of the azeotrope: the azeotropic temperature of water (15%) and C8 olefin (85%) is 75.3-81.4 ℃. Therefore, in the invention, after water is added for azeotropy in the azeotropic distillation tower, water, C8 hydrocarbon and ethylene glycol di-tert-butyl ether are all distilled to the tower top, part of ethylene glycol mono-tert-butyl ether is also distilled to the tower top, most of the ethylene glycol mono-tert-butyl ether falls to the tower bottom, and the ethylene glycol mono-tert-butyl ether is extracted through a discharge pipeline at the tower bottom to obtain the product ethylene glycol mono-tert-butyl ether. The overhead temperature of the azeotropic distillation tower is 95-105 ℃, preferably 96-104 ℃, more preferably 97-103 ℃, more preferably 98-102 ℃, more preferably 99-101 ℃, and further preferably 99-100 ℃, the overhead pressure is normal pressure, and the reflux ratio is 1-10: 1, preferably 2 to 9: 1, more preferably 2 to 8: 1, more preferably 2 to 7: 1, more preferably 2 to 6: 1, more preferably 2 to 5: 1, more preferably 2 to 4: 1, more preferably 2 to 3: 1.
in the invention, in order to ensure that the ethylene glycol di-tert-butyl ether in the product mixture material distilled from the top of the reduced pressure distillation tower can be completely distilled from the top of the azeotropic steam tower, the amount of the entrainer water added into the azeotropic distillation tower is 2-5 times, preferably 2-4 times, more preferably 2-3 times, and further preferably 2.5-3 times of the amount of the ethylene glycol di-tert-butyl ether contained in the product mixture distilled from the top of the reduced pressure distillation tower. According to calculation, the mass ratio of the added water to the product mixture fed into the azeotropic distillation tower is 10: 100-30: 100, preferably 10: 100-22: 100, more preferably 10: 100-16: 100, more preferably 14: 100-16: 100. the amount of the entrainer water added into the azeotropic distillation column can include or not include a mixture of ethylene glycol tert-butyl ether recycled from the water washing column and water, and preferably, the water washing water at the bottom of the water washing column can be returned to the azeotropic distillation column for recycling according to the principles of protecting the environment and saving resources.
In the invention, the mixture of ethylene glycol mono-tert-butyl ether, C8 hydrocarbon and ethylene glycol di-tert-butyl ether obtained from the top of the tower after azeotropic separation is a technical problem to be solved how to recover the ethylene glycol mono-tert-butyl ether in the mixture. In the invention, through experiments, the ethylene glycol di-tert-butyl ether and the C8 hydrocarbon are insoluble in water, and the ethylene glycol mono-tert-butyl ether is miscible with water, so that the ethylene glycol mono-tert-butyl ether can be effectively separated from the ethylene glycol di-tert-butyl ether and the C8 hydrocarbon through water washing. In the invention, a water scrubber is arranged behind an azeotropic distillation column to separate mixed ether obtained from the top of the distillation column, and the mass flow ratio of water in the water scrubber to a byproduct mixture obtained from the top of the azeotropic distillation column is 1-10: 1, preferably 2 to 8: 1, more preferably 2 to 6: 1, more preferably 2 to 5: 1. through water washing, the mixture of the ethylene glycol tert-butyl ether and water is obtained at the bottom of the tower and is recycled to the azeotropic distillation tower through a pipeline, so that the recovery of the ethylene glycol tert-butyl ether is realized, the yield of the ethylene glycol tert-butyl ether is greatly improved, and the yield of the ethylene glycol tert-butyl ether reaches more than 99 percent. The mixture of C8 hydrocarbon and glycol di-tert-butyl ether with water is obtained at the top of the water washing tower, and is subjected to standing and layering in a liquid separation tank, the mixture of glycol di-tert-butyl ether and C8 hydrocarbon is obtained at the upper layer, and water is obtained at the lower layer and can be recycled in the water washing tower through pipeline circulation. The purity of the ethylene glycol di-tert-butyl ether obtained after separation reaches more than 99 percent.
The present invention also provides a system for ethylene glycol t-butyl ether refining, the system comprising: a flash distillation tower and a decompression rectification tower, the device comprises an azeotropic rectifying tower and a water washing tower, wherein the flash tower is provided with a material feeding pipeline after the reaction of ethylene glycol and isobutene or mixed C4, the outlet at the top of the flash tower is connected with an unreacted isobutene or mixed C4 output pipeline, the outlet at the bottom of the flash tower is connected with the inlet of the reduced pressure rectifying tower through a pipeline, the outlet at the bottom of the reduced pressure rectifying tower is connected with a discharging pipeline of a mixed material of ethylene glycol and C12 hydrocarbon, the outlet at the top of the reduced pressure rectifying tower is connected with the inlet of the azeotropic rectifying tower, the outlet at the bottom of the azeotropic rectifying tower is connected with an ethylene glycol tert-butyl ether product output pipeline, the top outlet of the azeotropic rectifying tower is connected with the inlet at the lower part of the water washing tower, the inlet at the upper part of the water washing tower is connected with a desalted water feeding pipeline, the top of the water washing tower is.
Wherein, flash column, decompression rectifying column, azeotropic distillation tower respectively include top of the tower condenser and reflux drum and bottom of the tower reboiler, and the scrubbing tower contains the top of the tower branch liquid jar.
The unreacted isobutene or mixed C4 output line connected to the top outlet of the flash column was connected to the feed line of the reactor in which ethylene glycol was reacted with isobutene or mixed C4.
The outlet of the decompression rectification tower is connected with a mixed material discharging pipeline of the ethylene glycol and the C12 hydrocarbon, and the mixed material discharging pipeline is connected with the feeding pipeline of the reactor.
And a discharge pipeline of a mixture of the ethylene glycol mono-tert-butyl ether and water connected to the bottom of the water washing tower is connected with a water reflux inlet of the azeotropic distillation tower.
According to the invention, the high-purity ethylene glycol mono-tert-butyl ether and ethylene glycol di-tert-butyl ether can be effectively separated by the method, the purity of the separated ethylene glycol mono-tert-butyl ether is more than 99.5%, and the purity of the separated ethylene glycol di-tert-butyl ether is more than 99%. Meanwhile, the method greatly reduces the loss of the ethylene glycol mono-tert-butyl ether, and the yield of the main product ethylene glycol mono-tert-butyl ether is higher and reaches more than 99 percent. The method separates a large amount of unreacted glycol in the reaction material in the second step, avoids the material from entering a subsequent separation step to consume a large amount of energy consumption, greatly reduces the energy consumption, has short separation flow and low equipment investment, and is more favorable for industrialized production and technical popularization.
Drawings
FIG. 1 is a schematic view of the apparatus of the present invention.
Detailed Description
The invention is further illustrated by the following examples. However, the present invention is not limited to the following examples, and various changes may be made to the present invention within a range not departing from the gist of the present invention, and these changes are still included in the scope of the present invention.
As shown in fig. 1, the system for refining ethylene glycol t-butyl ether comprises: a flash tower 7, a vacuum rectification tower 14, an azeotropic rectification tower 21 and a water washing tower 27, wherein the flash tower is provided with a material feeding pipeline 6 after ethylene glycol and isobutene or mixed C4 react from a reactor 5, the outlet at the top of the flash tower is connected with an unreacted isobutene or mixed C4 output pipeline 11, the outlet at the bottom of the flash tower is connected with the inlet of the vacuum rectification tower 14 through a pipeline 13, the outlet at the bottom of the vacuum rectification tower 14 is connected with a discharge pipeline 20 of a mixed material of ethylene glycol and C12 hydrocarbon, the outlet at the top of the vacuum rectification tower 14 is connected with the inlet of the azeotropic rectification tower 21 through a pipeline 18, the outlet at the bottom of the azeotropic rectification tower 21 is connected with an ethylene glycol tert-butyl ether product output pipeline 27, the outlet at the top of the azeotropic rectification tower 21 is connected with the inlet at the lower part of the water washing tower 36 through a pipeline 25, the inlet at the upper part of the water washing tower is connected with a desalted water feeding pipeline 35, the bottom of the tower is connected with a discharge line 32 of the mixture of ethylene glycol mono-tert-butyl ether and water,
wherein the flash tower 7, the vacuum rectification tower 14 and the azeotropic rectification tower 21 respectively comprise a tower top condenser (8, 15, 22), a reflux tank (9, 16, 23) and a tower bottom reboiler (12, 19, 26), the reflux tanks 9, 16, 23 are respectively provided with reflux pipelines 10, 17, 24 returning to the flash tower 7, the vacuum rectification tower 14 and the azeotropic rectification tower 21, the upper part of the azeotropic rectification tower 21 is also connected with a desalted water feed 33,
the water washing tower 36 comprises a tower top liquid separating tank 29, the upper part of the liquid separating tank 29 is connected with a discharging pipeline 31 of ethylene glycol di-tert-butyl ether and C8 hydrocarbon olefin, and a discharging pipeline 30 connected with water at the bottom of the liquid separating tank 29 is directly connected to an upper inlet of the water washing tower 36 or connected to a desalted water feeding pipeline 35 connected to an upper inlet of the water washing tower.
The unreacted isobutene or mixed C4 outlet line connected to the top outlet of the flash column 2 is connected to the isobutene or mixed C4 feed line 2 upstream of the mixer 3 of the reactor 5 for the reaction of ethylene glycol with isobutene or mixed C4.
The outlet of the vacuum distillation tower 9 is connected with the outlet of the mixed material of ethylene glycol and C12 hydrocarbon, and is connected with the feed line 1 for ethylene glycol before the mixer 3, and the mixer 3 is connected with the inlet of the reactor 5 for reacting ethylene glycol with isobutene or mixed C4 through the feed pipe 4.
The discharging pipeline 32 of the mixture of the ethylene glycol mono-tert-butyl ether and the water connected to the bottom of the water washing tower 36 is connected to the desalted water feeding pipeline 33 of the azeotropic distillation tower 21.
Example 1
Extracting the material obtained after the reaction of ethylene glycol and isobutene from the reactor, and feeding the material into a flash tower, wherein the temperature at the top of the flash tower is 35 ℃, the pressure at the top of the flash tower is 0.3MPa, and the reflux ratio is 1: 1. after flash separation, unreacted isobutene is evaporated from the top of the tower, condensed by a condenser at the top of the tower and then enters a reflux tank at the top of the tower, part of materials are refluxed, and part of materials are pumped out from the reflux tank at the top of the tower and then returned to the reactor for cyclic utilization. The mixed material of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether, C8 hydrocarbon, C12 hydrocarbon and ethylene glycol falls into the bottom of the tower, and is sent into a reduced pressure rectifying tower after being cooled by a tower bottom cooler, wherein the tower top temperature of the reduced pressure rectifying tower is 40 ℃, the tower top pressure is-0.101 MPa, and the reflux ratio is 1: 1. the method comprises the following steps of (1) enabling a mixture of ethylene glycol and C12 hydrocarbon to fall into the bottom of a tower, cooling the mixture by a tower bottom cooler, returning the cooled mixture to a reactor for cyclic utilization, evaporating a product mixture of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether and C8 hydrocarbon from the top of the tower, condensing the product mixture by a tower top condenser, feeding the condensed product mixture into a tower top reflux tank, refluxing a part of materials, feeding a part of materials into an azeotropic distillation tower, controlling the tower top temperature of the azeotropic distillation tower to be 95 ℃, the: 1. adding entrainer water, wherein the amount of the added entrainer water is 2 times of the amount of ethylene glycol double tert-butyl ether contained in a product mixture distilled from the top of a vacuum distillation tower, performing azeotropic distillation to obtain a product ethylene glycol mono tert-butyl ether at the bottom of the tower, cooling the product ethylene glycol mono tert-butyl ether by a cooler at the bottom of the tower, sending the product ethylene glycol mono tert-butyl ether into a product tank, obtaining a mixture of ethylene glycol mono tert-butyl ether, ethylene glycol double tert-butyl ether, C8 hydrocarbon and water at the top of the tower, condensing the mixture by a condenser at the top of the tower, sending the mixture into a reflux tank at the top of the tower, layering the upper-layer material, sending the upper-layer material into a water: 1. and washing with water to obtain a mixture of ethylene glycol di-tert-butyl ether and C8 hydrocarbon at the tower top, and returning the mixture of ethylene glycol mono-tert-butyl ether and water obtained at the tower bottom to the azeotropic distillation tower for recycling.
The material at the bottom of the azeotropic distillation tower and the material at the top of the water washing tower are taken for analysis, the purity of the ethylene glycol mono-tert-butyl ether product at the bottom of the azeotropic distillation tower is 99.58 percent, the purity of the ethylene glycol di-tert-butyl ether product at the top of the water washing tower is 99.40 percent, and the yield of the ethylene glycol mono-tert-butyl ether is 99.42 percent after calculation.
Example 2
Extracting the material obtained after the reaction of ethylene glycol and isobutene from the reactor, and feeding the material into a flash tower, wherein the temperature at the top of the flash tower is 38 ℃, the pressure at the top of the flash tower is 0.32MPa, and the reflux ratio is 2: 1. after flash separation, unreacted isobutene is evaporated from the top of the tower, condensed by a condenser at the top of the tower and then enters a reflux tank at the top of the tower, part of materials are refluxed, and part of materials are pumped out from the reflux tank at the top of the tower and then returned to the reactor for cyclic utilization. The mixed material of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether, C8 hydrocarbon, C12 hydrocarbon and ethylene glycol falls into the bottom of the tower, and is sent into a reduced pressure rectifying tower after being cooled by a tower bottom cooler, wherein the tower top temperature of the reduced pressure rectifying tower is 41 ℃, the tower top pressure is-0.1 MPa, and the reflux ratio is 2: 1. the mixture of ethylene glycol and C12 hydrocarbon falls into the bottom of the tower and then is cooled by a tower bottom cooler and then returns to the reactor for cyclic utilization, the product mixture of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether and C8 hydrocarbon is steamed from the top of the tower and then is condensed by a tower top condenser and then enters a tower top reflux tank, part of the material is refluxed, part of the material is sent into an azeotropic distillation tower, the tower top temperature of the azeotropic distillation tower is 96 ℃, the tower top pressure is normal pressure, and the reflux ratio is 2: 1. adding entrainer water, wherein the amount of the added entrainer water is 2.5 times of the amount of ethylene glycol double tert-butyl ether contained in a product mixture distilled from the top of a reduced-pressure distillation tower, performing azeotropic distillation to obtain a product ethylene glycol mono tert-butyl ether at the bottom of the tower, cooling the product ethylene glycol mono tert-butyl ether by a tower bottom cooler, sending the product ethylene glycol mono tert-butyl ether into a product tank, obtaining an ethylene glycol mono tert-butyl ether, the ethylene glycol double tert-butyl ether, a C8 hydrocarbon and water mixture at the top of the tower, condensing the mixture by a tower top condenser, sending the mixture into a tower top reflux tank, layering, sending an upper-layer material into a water washing tower, and controlling the mass flow rate of water in the water washing: 1. and washing with water to obtain a mixture of ethylene glycol di-tert-butyl ether and C8 hydrocarbon at the tower top, and returning the mixture of ethylene glycol mono-tert-butyl ether and water obtained at the tower bottom to the azeotropic distillation tower for recycling.
The material at the bottom of the azeotropic distillation tower and the material at the top of the water washing tower are taken for analysis, the purity of the ethylene glycol mono-tert-butyl ether product at the bottom of the azeotropic distillation tower is 99.65 percent, the purity of the ethylene glycol di-tert-butyl ether product at the top of the water washing tower is 99.42 percent, and the yield of the ethylene glycol mono-tert-butyl ether is 99.4 percent after calculation.
Example 3
Extracting the material obtained after the reaction of ethylene glycol and isobutene from the reactor, and feeding the material into a flash tower, wherein the temperature at the top of the flash tower is 40 ℃, the pressure at the top of the flash tower is 0.35MPa, and the reflux ratio is 3: 1. after flash separation, unreacted isobutene is evaporated from the top of the tower, condensed by a condenser at the top of the tower and then enters a reflux tank at the top of the tower, part of materials are refluxed, and part of materials are pumped out from the reflux tank at the top of the tower and then returned to the reactor for cyclic utilization. The mixed material of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether, C8 hydrocarbon, C12 hydrocarbon and ethylene glycol falls into the bottom of the tower, and is sent into a reduced pressure rectifying tower after being cooled by a tower bottom cooler, wherein the tower top temperature of the reduced pressure rectifying tower is 42 ℃, the tower top pressure is-0.099 MPa, and the reflux ratio is 3: 1. the mixture of ethylene glycol and C12 hydrocarbon falls into the bottom of the tower and then is cooled by a tower bottom cooler and then returns to the reactor for cyclic utilization, the product mixture of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether and C8 hydrocarbon is steamed from the top of the tower and then is condensed by a tower top condenser and then enters a tower top reflux tank, part of the material is refluxed, part of the material is sent into an azeotropic distillation tower, the tower top temperature of the azeotropic distillation tower is 97 ℃, the tower top pressure is normal pressure, and the reflux ratio is 3: 1. adding entrainer water, wherein the amount of the added entrainer water is 2.8 times of the amount of ethylene glycol double tert-butyl ether contained in a product mixture distilled from the top of a reduced-pressure distillation tower, performing azeotropic distillation to obtain a product ethylene glycol mono tert-butyl ether at the bottom of the tower, cooling the product ethylene glycol mono tert-butyl ether by a tower bottom cooler, sending the product ethylene glycol mono tert-butyl ether into a product tank, obtaining an ethylene glycol mono tert-butyl ether, the ethylene glycol double tert-butyl ether, a C8 hydrocarbon and water mixture at the top of the tower, condensing the mixture by a tower top condenser, sending the mixture into a tower top reflux tank, layering, sending an upper-layer material into a water washing tower, and controlling the mass flow rate of water in the water washing: 1. and washing with water to obtain a mixture of ethylene glycol di-tert-butyl ether and C8 hydrocarbon at the tower top, and returning the mixture of ethylene glycol mono-tert-butyl ether and water obtained at the tower bottom to the azeotropic distillation tower for recycling.
The material at the bottom of the azeotropic distillation tower and the material at the top of the water washing tower are taken for analysis, the purity of the ethylene glycol mono-tert-butyl ether product at the bottom of the azeotropic distillation tower is 99.66 percent, the purity of the ethylene glycol di-tert-butyl ether product at the top of the water washing tower is 99.45 percent, and the yield of the ethylene glycol mono-tert-butyl ether is 99.42 percent after calculation.
Example 4
Extracting the material obtained after the reaction of ethylene glycol and isobutene from the reactor, and feeding the material into a flash tower, wherein the temperature at the top of the flash tower is 42 ℃, the pressure at the top of the flash tower is 0.38MPa, and the reflux ratio is 4: 1. after flash separation, unreacted isobutene is evaporated from the top of the tower, condensed by a condenser at the top of the tower and then enters a reflux tank at the top of the tower, part of materials are refluxed, and part of materials are pumped out from the reflux tank at the top of the tower and then returned to the reactor for cyclic utilization. The mixed material of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether, C8 hydrocarbon, C12 hydrocarbon and ethylene glycol falls into the bottom of the tower, and is sent into a reduced pressure rectifying tower after being cooled by a tower bottom cooler, wherein the tower top temperature of the reduced pressure rectifying tower is 44 ℃, the tower top pressure is-0.098 MPa, and the reflux ratio is 4: 1. the mixture of ethylene glycol and C12 hydrocarbon falls into the bottom of the tower and then is cooled by a tower bottom cooler and then returns to the reactor for cyclic utilization, the product mixture of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether and C8 hydrocarbon is steamed from the top of the tower and then is condensed by a tower top condenser and then enters a tower top reflux tank, part of the material is refluxed, part of the material is sent into an azeotropic distillation tower, the tower top temperature of the azeotropic distillation tower is 98 ℃, the tower top pressure is normal pressure, and the reflux ratio is 4: 1. adding entrainer water, wherein the amount of the added entrainer water is 3 times of the amount of ethylene glycol double tert-butyl ether contained in a product mixture distilled from the top of a vacuum rectification tower, performing azeotropic rectification to obtain a product ethylene glycol mono tert-butyl ether at the bottom of the tower, cooling the product ethylene glycol mono tert-butyl ether by a cooler at the bottom of the tower, sending the product ethylene glycol mono-tert-butyl ether into a product tank, obtaining a mixture of ethylene glycol mono-tert-butyl ether, ethylene glycol double tert-butyl ether, C8 hydrocarbon and water at the top of the tower, condensing the mixture by a condenser at the top of the tower, sending the upper-layer material into a water washing tower after layering, and controlling the mass flow rate of the water in the water washing tower: 1. and washing with water to obtain a mixture of ethylene glycol di-tert-butyl ether and C8 hydrocarbon at the tower top, and returning the mixture of ethylene glycol mono-tert-butyl ether and water obtained at the tower bottom to the azeotropic distillation tower for recycling.
And (3) analyzing the materials at the bottom of the azeotropic distillation tower and the materials at the top of the water washing tower, wherein the purity of the ethylene glycol mono-tert-butyl ether product of the materials at the bottom of the azeotropic distillation tower is 99.68 percent, the purity of the ethylene glycol di-tert-butyl ether product of the materials at the top of the water washing tower is 99.48 percent, and the yield of the ethylene glycol mono-tert-butyl ether is 99.45 percent after calculation.
Example 5
Extracting the material obtained after the reaction of ethylene glycol and isobutene from the reactor, and feeding the material into a flash tower, wherein the temperature at the top of the flash tower is 45 ℃, the pressure at the top of the flash tower is 0.4MPa, and the reflux ratio is 5: 1. after flash separation, unreacted isobutene is evaporated from the top of the tower, condensed by a condenser at the top of the tower and then enters a reflux tank at the top of the tower, part of materials are refluxed, and part of materials are pumped out from the reflux tank at the top of the tower and then returned to the reactor for cyclic utilization. The mixed material of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether, C8 hydrocarbon, C12 hydrocarbon and ethylene glycol falls into the bottom of the tower, and is sent into a reduced pressure rectifying tower after being cooled by a tower bottom cooler, wherein the tower top temperature of the reduced pressure rectifying tower is 45 ℃, the tower top pressure is-0.096 MPa, and the reflux ratio is 5: 1. the mixture of ethylene glycol and C12 hydrocarbon falls into the bottom of the tower and is cooled by a tower bottom cooler and then returns to the reactor for cyclic utilization, the product mixture of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether and C8 hydrocarbon is steamed from the top of the tower and then is condensed by a tower top condenser and then enters a tower top reflux tank, part of the material is refluxed, part of the material is sent into an azeotropic distillation tower, the tower top temperature of the azeotropic distillation tower is 99 ℃, the tower top pressure is normal pressure, and the reflux ratio is 5: 1. adding entrainer water, wherein the amount of the added entrainer water is 3.5 times of the amount of ethylene glycol double tert-butyl ether contained in a product mixture distilled from the top of a reduced-pressure distillation tower, performing azeotropic distillation to obtain a product ethylene glycol mono tert-butyl ether at the bottom of the tower, cooling the product ethylene glycol mono tert-butyl ether by a tower bottom cooler, sending the product ethylene glycol mono tert-butyl ether into a product tank, obtaining an ethylene glycol mono tert-butyl ether, the ethylene glycol double tert-butyl ether, a C8 hydrocarbon and water mixture at the top of the tower, condensing the mixture by a tower top condenser, sending the mixture into a tower top reflux tank, layering, sending an upper-layer material into a water washing tower, and controlling the mass flow rate of water in the water washing: 1. and washing with water to obtain a mixture of ethylene glycol di-tert-butyl ether and C8 hydrocarbon at the tower top, and returning the mixture of ethylene glycol mono-tert-butyl ether and water obtained at the tower bottom to the azeotropic distillation tower for recycling.
And (3) analyzing the materials at the bottom of the azeotropic distillation tower and the materials at the top of the water washing tower, wherein the purity of the ethylene glycol mono-tert-butyl ether product of the materials at the bottom of the azeotropic distillation tower is 99.7 percent, the purity of the ethylene glycol di-tert-butyl ether product of the materials at the top of the water washing tower is 99.5 percent, and the yield of the ethylene glycol mono-tert-butyl ether is 99.5 percent after calculation.
Example 6
Extracting the material obtained after the reaction of ethylene glycol and isobutene from the reactor, and feeding the material into a flash tower, wherein the temperature at the top of the flash tower is 50 ℃, the pressure at the top of the flash tower is 0.45MPa, and the reflux ratio is 6: 1. after flash separation, unreacted isobutene is evaporated from the top of the tower, condensed by a condenser at the top of the tower and then enters a reflux tank at the top of the tower, part of materials are refluxed, and part of materials are pumped out from the reflux tank at the top of the tower and then returned to the reactor for cyclic utilization. The mixed material of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether, C8 hydrocarbon, C12 hydrocarbon and ethylene glycol falls into the bottom of the tower, and is sent into a reduced pressure rectifying tower after being cooled by a tower bottom cooler, wherein the tower top temperature of the reduced pressure rectifying tower is 46 ℃, the tower top pressure is-0.095 MPa, and the reflux ratio is 6: 1. the mixture of ethylene glycol and C12 hydrocarbon falls into the bottom of the tower and then is cooled by a tower bottom cooler and then returns to the reactor for cyclic utilization, the product mixture of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether and C8 hydrocarbon is steamed from the top of the tower and then is condensed by a tower top condenser and then enters a tower top reflux tank, part of the material is refluxed, part of the material is sent into an azeotropic distillation tower, the tower top temperature of the azeotropic distillation tower is 100 ℃, the tower top pressure is normal pressure, and the reflux ratio is 6: 1. adding entrainer water, wherein the amount of the added entrainer water is 3.8 times of the amount of ethylene glycol double tert-butyl ether contained in a product mixture distilled from the top of a reduced-pressure distillation tower, performing azeotropic distillation to obtain a product ethylene glycol mono tert-butyl ether at the bottom of the tower, cooling the product ethylene glycol mono tert-butyl ether by a tower bottom cooler, sending the product ethylene glycol mono tert-butyl ether into a product tank, obtaining an ethylene glycol mono tert-butyl ether, the ethylene glycol double tert-butyl ether, a C8 hydrocarbon and water mixture at the top of the tower, condensing the mixture by a tower top condenser, sending the mixture into a tower top reflux tank, layering, sending an upper-layer material into a water washing tower, and controlling the mass flow rate of water in the water washing: 1. and washing with water to obtain a mixture of ethylene glycol di-tert-butyl ether and C8 hydrocarbon at the tower top, and returning the mixture of ethylene glycol mono-tert-butyl ether and water obtained at the tower bottom to the azeotropic distillation tower for recycling.
Analyzing the materials at the bottom of the azeotropic distillation tower and the materials at the top of the water washing tower, wherein the purity of the ethylene glycol mono-tert-butyl ether product at the bottom of the azeotropic distillation tower is 99.72%, the purity of the ethylene glycol di-tert-butyl ether product at the top of the water washing tower is 99.52%, and the yield of the ethylene glycol mono-tert-butyl ether is 99.55% after calculation.
Example 7
Extracting the material obtained after the reaction of ethylene glycol and isobutene from the reactor, and feeding the material into a flash tower, wherein the temperature at the top of the flash tower is 55 ℃, the pressure at the top of the flash tower is 0.5MPa, and the reflux ratio is 7: 1. after flash separation, unreacted isobutene is evaporated from the top of the tower, condensed by a condenser at the top of the tower and then enters a reflux tank at the top of the tower, part of materials are refluxed, and part of materials are pumped out from the reflux tank at the top of the tower and then returned to the reactor for cyclic utilization. The mixed material of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether, C8 hydrocarbon, C12 hydrocarbon and ethylene glycol falls into the bottom of the tower, and is sent into a reduced pressure rectifying tower after being cooled by a tower bottom cooler, wherein the tower top temperature of the reduced pressure rectifying tower is 47 ℃, the tower top pressure is-0.094 MPa, and the reflux ratio is 7: 1. the mixture of ethylene glycol and C12 hydrocarbon falls into the bottom of the tower and then is cooled by a tower bottom cooler and then returns to the reactor for cyclic utilization, the product mixture of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether and C8 hydrocarbon is steamed from the top of the tower and then is condensed by a tower top condenser and then enters a tower top reflux tank, part of the material is refluxed, part of the material is sent into an azeotropic distillation tower, the tower top temperature of the azeotropic distillation tower is 101 ℃, the tower top pressure is normal pressure, and the reflux ratio is 7: 1. adding entrainer water, wherein the amount of the added entrainer water is 4 times of the amount of ethylene glycol double tert-butyl ether contained in a product mixture distilled from the top of a reduced-pressure distillation tower, performing azeotropic distillation to obtain a product ethylene glycol mono tert-butyl ether at the bottom of the tower, cooling the product ethylene glycol mono tert-butyl ether by a tower bottom cooler, sending the product ethylene glycol mono tert-butyl ether into a product tank, obtaining a mixture of ethylene glycol mono tert-butyl ether, ethylene glycol double tert-butyl ether, C8 hydrocarbon and water at the top of the tower, condensing the mixture by a tower top condenser, sending the mixture into a tower top reflux tank, layering, sending an upper-layer material into a water washing tower, and controlling the mass flow rate of water in the water washing tower: 1. and washing with water to obtain a mixture of ethylene glycol di-tert-butyl ether and C8 hydrocarbon at the tower top, and returning the mixture of ethylene glycol mono-tert-butyl ether and water obtained at the tower bottom to the azeotropic distillation tower for recycling.
The material at the bottom of the azeotropic distillation tower and the material at the top of the water washing tower are taken for analysis, the purity of the ethylene glycol mono-tert-butyl ether product at the bottom of the azeotropic distillation tower is 99.75 percent, the purity of the ethylene glycol di-tert-butyl ether product at the top of the water washing tower is 99.55 percent, and the yield of the ethylene glycol mono-tert-butyl ether is 99.6 percent after calculation.
Example 8
Extracting the material obtained after the reaction of ethylene glycol and isobutene from the reactor and sending the material into a flash tower, wherein the temperature at the top of the flash tower is 60 ℃, the pressure at the top of the flash tower is 0.52MPa, and the reflux ratio is 8: 1. after flash separation, unreacted isobutene is evaporated from the top of the tower, condensed by a condenser at the top of the tower and then enters a reflux tank at the top of the tower, part of materials are refluxed, and part of materials are pumped out from the reflux tank at the top of the tower and then returned to the reactor for cyclic utilization. The mixed material of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether, C8 hydrocarbon, C12 hydrocarbon and ethylene glycol falls into the bottom of the tower, and is sent into a reduced pressure rectifying tower after being cooled by a tower bottom cooler, wherein the tower top temperature of the reduced pressure rectifying tower is 48 ℃, the tower top pressure is-0.092 MPa, and the reflux ratio is 8: 1. the mixture of ethylene glycol and C12 hydrocarbon falls into the bottom of the tower and is cooled by a tower bottom cooler and then returns to the reactor for cyclic utilization, the product mixture of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether and C8 hydrocarbon is steamed from the top of the tower and then is condensed by a tower top condenser and then enters a tower top reflux tank, part of the material is refluxed, part of the material is sent into an azeotropic distillation tower, the tower top temperature of the azeotropic distillation tower is 102 ℃, the tower top pressure is normal pressure, and the reflux ratio is 8: 1. adding entrainer water, wherein the amount of the added entrainer water is 4.5 times of the amount of ethylene glycol double tert-butyl ether contained in a product mixture distilled from the top of a reduced-pressure distillation tower, performing azeotropic distillation to obtain a product ethylene glycol mono tert-butyl ether at the bottom of the tower, cooling the product ethylene glycol mono tert-butyl ether by a tower bottom cooler, sending the product ethylene glycol mono tert-butyl ether into a product tank, obtaining an ethylene glycol mono tert-butyl ether, the ethylene glycol double tert-butyl ether, a C8 hydrocarbon and water mixture at the top of the tower, condensing the mixture by a tower top condenser, sending the mixture into a tower top reflux tank, layering, sending an upper-layer material into a water washing tower, and controlling the mass flow rate of water in the water washing: 1. and washing with water to obtain a mixture of ethylene glycol di-tert-butyl ether and C8 hydrocarbon at the tower top, and returning the mixture of ethylene glycol mono-tert-butyl ether and water obtained at the tower bottom to the azeotropic distillation tower for recycling.
The material at the bottom of the azeotropic distillation tower and the material at the top of the water washing tower are taken for analysis, the purity of the ethylene glycol mono-tert-butyl ether product at the bottom of the azeotropic distillation tower is 99.78 percent, the purity of the ethylene glycol di-tert-butyl ether product at the top of the water washing tower is 99.58 percent, and the yield of the ethylene glycol mono-tert-butyl ether is 99.62 percent after calculation.
Example 9
Extracting the material obtained after the reaction of ethylene glycol and isobutene from the reactor, and feeding the material into a flash tower, wherein the temperature at the top of the flash tower is 65 ℃, the pressure at the top of the flash tower is 0.55MPa, and the reflux ratio is 9: 1. after flash separation, unreacted isobutene is evaporated from the top of the tower, condensed by a condenser at the top of the tower and then enters a reflux tank at the top of the tower, part of materials are refluxed, and part of materials are pumped out from the reflux tank at the top of the tower and then returned to the reactor for cyclic utilization. The mixed material of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether, C8 hydrocarbon, C12 hydrocarbon and ethylene glycol falls into the bottom of the tower, and is sent into a reduced pressure rectifying tower after being cooled by a tower bottom cooler, wherein the tower top temperature of the reduced pressure rectifying tower is 49 ℃, the tower top pressure is-0.09 MPa, and the reflux ratio is 9: 1. the mixture of ethylene glycol and C12 hydrocarbon falls into the bottom of the tower and is cooled by a tower bottom cooler and then returns to the reactor for cyclic utilization, the product mixture of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether and C8 hydrocarbon is steamed from the top of the tower and then is condensed by a tower top condenser and then enters a tower top reflux tank, part of the material is refluxed, part of the material is sent into an azeotropic distillation tower, the tower top temperature of the azeotropic distillation tower is 103 ℃, the tower top pressure is normal pressure, and the reflux ratio is 9: 1. adding entrainer water, wherein the amount of the added entrainer water is 4.8 times of the amount of ethylene glycol double tert-butyl ether contained in a product mixture distilled from the top of a reduced-pressure distillation tower, performing azeotropic distillation to obtain a product ethylene glycol mono tert-butyl ether at the bottom of the tower, cooling the product ethylene glycol mono tert-butyl ether by a tower bottom cooler, sending the product ethylene glycol mono tert-butyl ether into a product tank, obtaining an ethylene glycol mono tert-butyl ether, the ethylene glycol double tert-butyl ether, a C8 hydrocarbon and water mixture at the top of the tower, condensing the mixture by a tower top condenser, sending the mixture into a tower top reflux tank, layering, sending an upper-layer material into a water washing tower, and controlling the mass flow rate of water in the water washing: 1. and washing with water to obtain a mixture of ethylene glycol di-tert-butyl ether and C8 hydrocarbon at the tower top, and returning the mixture of ethylene glycol mono-tert-butyl ether and water obtained at the tower bottom to the azeotropic distillation tower for recycling.
The material at the bottom of the azeotropic distillation tower and the material at the top of the water washing tower are taken for analysis, the purity of the ethylene glycol mono-tert-butyl ether product at the bottom of the azeotropic distillation tower is 99.80 percent, the purity of the ethylene glycol di-tert-butyl ether product at the top of the water washing tower is 99.60 percent, and the yield of the ethylene glycol mono-tert-butyl ether is 99.65 percent after calculation.
Example 10
Extracting the material obtained after the reaction of ethylene glycol and isobutene from the reactor, and feeding the material into a flash tower, wherein the temperature at the top of the flash tower is 70 ℃, the pressure at the top of the flash tower is 0.6MPa, and the reflux ratio is 10: 1. after flash separation, unreacted isobutene is evaporated from the top of the tower, condensed by a condenser at the top of the tower and then enters a reflux tank at the top of the tower, part of materials are refluxed, and part of materials are pumped out from the reflux tank at the top of the tower and then returned to the reactor for cyclic utilization. The mixed material of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether, C8 hydrocarbon, C12 hydrocarbon and ethylene glycol falls into the bottom of the tower, and is sent into a reduced pressure rectifying tower after being cooled by a tower bottom cooler, wherein the tower top temperature of the reduced pressure rectifying tower is 50 ℃, the tower top pressure is-0.089 MPa, and the reflux ratio is 10: 1. the mixture of ethylene glycol and C12 hydrocarbon falls into the bottom of the tower and is cooled by a tower bottom cooler and then returns to the reactor for cyclic utilization, the product mixture of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether and C8 hydrocarbon is steamed from the top of the tower and then is condensed by a tower top condenser and then enters a tower top reflux tank, part of the material is refluxed, part of the material is sent into an azeotropic distillation tower, the tower top temperature of the azeotropic distillation tower is 105 ℃, the tower top pressure is normal pressure, and the reflux ratio is 10: 1. adding entrainer water, wherein the amount of the added entrainer water is 5 times of the amount of ethylene glycol double tert-butyl ether contained in a product mixture distilled from the top of a vacuum distillation tower, performing azeotropic distillation to obtain a product ethylene glycol mono tert-butyl ether at the bottom of the tower, cooling the product ethylene glycol mono tert-butyl ether by a cooler at the bottom of the tower, sending the product ethylene glycol mono tert-butyl ether into a product tank, obtaining a mixture of ethylene glycol mono tert-butyl ether, ethylene glycol double tert-butyl ether, C8 hydrocarbon and water at the top of the tower, condensing the mixture by a condenser at the top of the tower, sending the mixture into a reflux tank at the top of the tower, layering the upper-layer material, sending the upper-layer material into a water: 1. and washing with water to obtain a mixture of ethylene glycol di-tert-butyl ether and C8 hydrocarbon at the tower top, and returning the mixture of ethylene glycol mono-tert-butyl ether and water obtained at the tower bottom to the azeotropic distillation tower for recycling.
And (3) analyzing the materials at the bottom of the azeotropic distillation tower and the materials at the top of the water washing tower, wherein the purity of the ethylene glycol mono-tert-butyl ether product of the materials at the bottom of the azeotropic distillation tower is 99.85 percent, the purity of the ethylene glycol di-tert-butyl ether product of the materials at the top of the water washing tower is 99.65 percent, and the yield of the ethylene glycol mono-tert-butyl ether is 99.7 percent after calculation.
Claims (10)
1. A method for refining ethylene glycol tert-butyl ether comprises (1) pumping the material obtained by reacting ethylene glycol with isobutene or mixed C4 out of a reactor, feeding into a flash tower, separating by flash evaporation, evaporating unreacted isobutene or mixed C4 from the top of the tower, and returning to the reactor for recycling, wherein the mixed material of ethylene glycol tert-butyl ether, ethylene glycol di-tert-butyl ether, C8 hydrocarbon, C12 hydrocarbon and ethylene glycol falls into the bottom of the tower;
(2) feeding the mixed material from the bottom of the flash tower into a vacuum rectification tower, pumping out the mixture of ethylene glycol and C12 hydrocarbon after falling into the bottom of the tower, returning the mixture to the reactor for recycling, and evaporating a product mixture of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether and C8 hydrocarbon from the top of the tower;
(3) feeding the product mixture distilled from the top of the reduced pressure distillation tower into an azeotropic distillation tower, adding entrainer water, performing azeotropic distillation to obtain a product ethylene glycol mono-tert-butyl ether at the bottom of the tower, and obtaining a byproduct mixture of ethylene glycol mono-tert-butyl ether, ethylene glycol di-tert-butyl ether and C8 hydrocarbon at the top of the tower;
(4) and (3) feeding the byproduct mixture obtained from the top of the azeotropic distillation tower into a water washing tower, and washing to obtain a mixture of ethylene glycol di-tert-butyl ether and C8 hydrocarbon at the top of the tower, preferably, obtaining a mixture of ethylene glycol mono-tert-butyl ether and water at the bottom of the tower and returning the mixture to the azeotropic distillation tower for recycling.
2. The method of claim 1, wherein the overhead temperature of the flash column is 35 to 70 ℃, the overhead pressure is 0.3 to 0.6MPa, and the reflux ratio is 1 to 10: 1.
3. the method according to claim 1 or 2, wherein the top temperature of the vacuum distillation tower is 40-50 ℃, the top pressure is-0.101 MPa to-0.089 MPa, and the reflux ratio is 1-10: 1, preferably 2 to 5: 1.
4. the process according to claim 1 or 2, wherein the overhead temperature of the azeotropic distillation column is 95 to 105 ℃, preferably 98 to 102 ℃, the overhead pressure is atmospheric pressure, and the reflux ratio is 1 to 10: 1, preferably 2 to 5: 1.
5. the method as claimed in claim 1 or 2, wherein the mass flow rate of the water in the water washing tower and the mass flow rate of the byproduct mixture obtained from the top of the azeotropic distillation tower are in a ratio of 1-10: 1, preferably 2 to 8: 1, more preferably 2 to 6: 1, more preferably 2 to 5: 1.
6. the method according to claim 1, wherein the amount of the azeotropic agent water added to the azeotropic distillation tower is 2 to 5 times, preferably 2 to 4 times, more preferably 2 to 3 times, and still more preferably 2.5 to 3 times the amount of the ethylene glycol di-t-butyl ether contained in the product mixture distilled out at the top of the vacuum distillation tower.
7. A system for ethylene glycol tert-butyl ether refining, the system comprising: a flash distillation tower and a decompression rectification tower, the device comprises an azeotropic rectifying tower and a water washing tower, wherein the flash tower is provided with a material feeding pipeline after the reaction of ethylene glycol and isobutene or mixed C4, the outlet at the top of the flash tower is connected with an unreacted isobutene or mixed C4 output pipeline, the outlet at the bottom of the flash tower is connected with the inlet of the reduced pressure rectifying tower through a pipeline, the outlet at the bottom of the reduced pressure rectifying tower is connected with a discharging pipeline of a mixed material of ethylene glycol and C12 hydrocarbon, the outlet at the top of the reduced pressure rectifying tower is connected with the inlet of the azeotropic rectifying tower, the outlet at the bottom of the azeotropic rectifying tower is connected with an ethylene glycol tert-butyl ether product output pipeline, the top outlet of the azeotropic rectifying tower is connected with the inlet at the lower part of the water washing tower, the inlet at the upper part of the water washing tower is connected with a desalted water feeding pipeline, the top of the water washing tower is;
wherein, flash column, decompression rectifying column, azeotropic distillation tower respectively include top of the tower condenser and reflux drum and bottom of the tower reboiler, and the scrubbing tower contains the top of the tower branch liquid jar.
8. The process according to claim 7, wherein the unreacted isobutylene or mixed C4 outlet line connected to the top outlet of the flash column is connected to the feed line of the reactor.
9. The process according to claim 7 or 8, characterized in that the outlet of the vacuum distillation column from the bottom of the column is connected to the feed line of the reactor to which the outlet of the mixture of ethylene glycol and C12 hydrocarbons is connected.
10. The method according to claim 7 or 8, wherein a discharge pipeline of a mixture of the ethylene glycol mono-tert-butyl ether and water connected to the bottom of the water washing tower is connected with a water reflux inlet of the azeotropic distillation tower.
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0035075A1 (en) * | 1980-02-29 | 1981-09-09 | Maruzen Petrochemical Co., Ltd. | Process for producing ethylene glycol mono-t-butyl ether |
| CN1065655A (en) * | 1991-04-09 | 1992-10-28 | 中国石油化工总公司扬子石油化工公司 | Making with extra care of diglycol monotertiary butyl ether |
| US6264800B1 (en) * | 2000-07-19 | 2001-07-24 | Arco Chemical Technology, L.P. | Purification process |
| US20110306803A1 (en) * | 2010-06-14 | 2011-12-15 | Daelim Industrial Co., Ltd. | Separation of glycol mono-tertiary-butyl ether and glycol di-tertiary-butyl ether |
| CN205974325U (en) * | 2016-08-18 | 2017-02-22 | 天津海成能源工程技术有限公司 | Energy-saving device for separating ethylene glycol mono-tert-butyl ether and ethylene glycol di-tert-butyl ether |
| CN106748668A (en) * | 2016-11-15 | 2017-05-31 | 潍坊康顺化工有限公司 | Ethylene glycol tertbutyl ether and its production technology |
| CN107434762A (en) * | 2017-03-10 | 2017-12-05 | 孙广 | A kind of preparation of ethylene glycol mono-tert-butyl ether and process for purification |
| CN107739300A (en) * | 2017-10-23 | 2018-02-27 | 黄河三角洲京博化工研究院有限公司 | A kind of process for producing high-purity isobutene and ethylene glycol mono-tert-butyl ether |
| CN207552209U (en) * | 2017-10-23 | 2018-06-29 | 黄河三角洲京博化工研究院有限公司 | A kind of process unit for producing ethylene glycol mono-tert-butyl ether |
-
2018
- 2018-12-04 CN CN201811470510.XA patent/CN111269095B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0035075A1 (en) * | 1980-02-29 | 1981-09-09 | Maruzen Petrochemical Co., Ltd. | Process for producing ethylene glycol mono-t-butyl ether |
| CN1065655A (en) * | 1991-04-09 | 1992-10-28 | 中国石油化工总公司扬子石油化工公司 | Making with extra care of diglycol monotertiary butyl ether |
| US6264800B1 (en) * | 2000-07-19 | 2001-07-24 | Arco Chemical Technology, L.P. | Purification process |
| US20110306803A1 (en) * | 2010-06-14 | 2011-12-15 | Daelim Industrial Co., Ltd. | Separation of glycol mono-tertiary-butyl ether and glycol di-tertiary-butyl ether |
| CN205974325U (en) * | 2016-08-18 | 2017-02-22 | 天津海成能源工程技术有限公司 | Energy-saving device for separating ethylene glycol mono-tert-butyl ether and ethylene glycol di-tert-butyl ether |
| CN106748668A (en) * | 2016-11-15 | 2017-05-31 | 潍坊康顺化工有限公司 | Ethylene glycol tertbutyl ether and its production technology |
| CN107434762A (en) * | 2017-03-10 | 2017-12-05 | 孙广 | A kind of preparation of ethylene glycol mono-tert-butyl ether and process for purification |
| CN107739300A (en) * | 2017-10-23 | 2018-02-27 | 黄河三角洲京博化工研究院有限公司 | A kind of process for producing high-purity isobutene and ethylene glycol mono-tert-butyl ether |
| CN207552209U (en) * | 2017-10-23 | 2018-06-29 | 黄河三角洲京博化工研究院有限公司 | A kind of process unit for producing ethylene glycol mono-tert-butyl ether |
Non-Patent Citations (1)
| Title |
|---|
| 沈景余: ""国外乙二醇叔丁基醚的生产和利用"", 《精细石油化工》 * |
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