CN118146092A - Refined methyl acetate and production process and production system thereof - Google Patents
Refined methyl acetate and production process and production system thereof Download PDFInfo
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- XBDQKXXYIPTUBI-UHFFFAOYSA-M Propionate Chemical compound CCC([O-])=O XBDQKXXYIPTUBI-UHFFFAOYSA-M 0.000 title claims abstract description 109
- KXKVLQRXCPHEJC-UHFFFAOYSA-N acetic acid trimethyl ester Natural products COC(C)=O KXKVLQRXCPHEJC-UHFFFAOYSA-N 0.000 title claims abstract description 109
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 27
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 claims abstract description 77
- 239000007788 liquid Substances 0.000 claims abstract description 19
- 239000004372 Polyvinyl alcohol Substances 0.000 claims abstract description 9
- 239000006227 byproduct Substances 0.000 claims abstract description 9
- 229920002451 polyvinyl alcohol Polymers 0.000 claims abstract description 9
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims description 72
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 claims description 60
- IKHGUXGNUITLKF-UHFFFAOYSA-N Acetaldehyde Chemical compound CC=O IKHGUXGNUITLKF-UHFFFAOYSA-N 0.000 claims description 28
- 239000000203 mixture Substances 0.000 claims description 17
- 238000007670 refining Methods 0.000 claims description 17
- 238000004821 distillation Methods 0.000 claims description 16
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 claims description 13
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims description 12
- 238000010992 reflux Methods 0.000 claims description 9
- 238000000034 method Methods 0.000 claims description 8
- IKHGUXGNUITLKF-XPULMUKRSA-N acetaldehyde Chemical compound [14CH]([14CH3])=O IKHGUXGNUITLKF-XPULMUKRSA-N 0.000 claims description 7
- XTXRWKRVRITETP-UHFFFAOYSA-N Vinyl acetate Chemical compound CC(=O)OC=C XTXRWKRVRITETP-UHFFFAOYSA-N 0.000 claims description 3
- 238000001704 evaporation Methods 0.000 claims description 3
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- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 description 6
- 125000003827 glycol group Chemical group 0.000 description 4
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- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 description 2
- DKPFZGUDAPQIHT-UHFFFAOYSA-N Butyl acetate Natural products CCCCOC(C)=O DKPFZGUDAPQIHT-UHFFFAOYSA-N 0.000 description 2
- RGSFGYAAUTVSQA-UHFFFAOYSA-N Cyclopentane Chemical compound C1CCCC1 RGSFGYAAUTVSQA-UHFFFAOYSA-N 0.000 description 2
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- FUZZWVXGSFPDMH-UHFFFAOYSA-N hexanoic acid Chemical compound CCCCCC(O)=O FUZZWVXGSFPDMH-UHFFFAOYSA-N 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 150000004702 methyl esters Chemical class 0.000 description 2
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- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N 2-Propenoic acid Natural products OC(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- KXGFMDJXCMQABM-UHFFFAOYSA-N 2-methoxy-6-methylphenol Chemical compound [CH]OC1=CC=CC([CH])=C1O KXGFMDJXCMQABM-UHFFFAOYSA-N 0.000 description 1
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- FJWGYAHXMCUOOM-QHOUIDNNSA-N [(2s,3r,4s,5r,6r)-2-[(2r,3r,4s,5r,6s)-4,5-dinitrooxy-2-(nitrooxymethyl)-6-[(2r,3r,4s,5r,6s)-4,5,6-trinitrooxy-2-(nitrooxymethyl)oxan-3-yl]oxyoxan-3-yl]oxy-3,5-dinitrooxy-6-(nitrooxymethyl)oxan-4-yl] nitrate Chemical compound O([C@@H]1O[C@@H]([C@H]([C@H](O[N+]([O-])=O)[C@H]1O[N+]([O-])=O)O[C@H]1[C@@H]([C@@H](O[N+]([O-])=O)[C@H](O[N+]([O-])=O)[C@@H](CO[N+]([O-])=O)O1)O[N+]([O-])=O)CO[N+](=O)[O-])[C@@H]1[C@@H](CO[N+]([O-])=O)O[C@@H](O[N+]([O-])=O)[C@H](O[N+]([O-])=O)[C@H]1O[N+]([O-])=O FJWGYAHXMCUOOM-QHOUIDNNSA-N 0.000 description 1
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- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses refined methyl acetate which comprises ethylene glycol which is less than or equal to 0.0010 percent and methyl acetate which is more than or equal to 99.98 percent, wherein the methyl acetate is a byproduct in the production of polyvinyl alcohol. According to the invention, crude methyl acetate recovered from alcoholysis waste liquid is used as a raw material, ethylene glycol is used as an extractant, and a multi-tower rectification mode is adopted, so that refined methyl acetate with purity of more than 99.98% is obtained, and the loss rate of methyl acetate is reduced; the invention can recycle the ethylene glycol for a long time, can continuously purify the ethylene glycol, and ensures the effect of extracting the methyl acetate from the recycled ethylene glycol.
Description
Technical Field
The invention relates to refined methyl acetate, in particular to refined methyl acetate serving as a byproduct in the production of polyvinyl alcohol, and a production process and a production system thereof.
Background
Methyl acetate is used as a colorless transparent quick-drying solvent with a low boiling point, and the volatilization speed of the quick-drying solvent is very similar to that of acetone and slightly faster than that of ethyl acetate and butyl acetate. Meanwhile, the methyl acetate has higher flash point and anti-whitening performance (the whitening condition of the adhesive surface after quick drying is less), and in the process formula of the volatile organic solvent with a low boiling point, the methyl acetate can partially replace ethyl acetate, butyl acetate, cyclopentane, acetone, butanone and the like. The methyl acetate does not belong to the emission of organic pollutants for limiting use, and can reach the new environmental protection standard of paint, printing ink, resin and adhesive factories. Has wide dissolving power, and can dissolve acrylic acid, vinyl, nitrocellulose, epoxy, polyurethane, polyester, phenolic resin, etc. Therefore, the methyl acetate can be widely applied to the fields of producing paint cleaning agents, fuel system cleaning agents and assistants, polymer solvents, foaming agents, fine chemical engineering, medical intermediates and the like.
At present, methyl acetate is produced by two processes, namely methanol and acetic acid are used as raw materials, and unreacted residual monomers are separated by rectification through esterification reaction; secondly, by-products in the polyvinyl alcohol production process are used as raw materials, methanol, acetaldehyde, acetone, water and the like are separated through rectification, and methyl acetate is obtained, and the latter takes the dominant place. The invention adopts the second production process to produce the methyl acetate.
Chinese patent document CN205035300U discloses a production system of high purity methyl acetate, comprising: the device comprises a first rectifying tower (1), a second rectifying tower (2) and a third rectifying tower (3), wherein the first rectifying tower (1) is respectively connected with the second rectifying tower (2) and the third rectifying tower (3). According to the utility model, crude methyl acetate recovered from alcoholysis waste liquid is used as a raw material, ethylene glycol is used as an extractant, and a three-tower rectification mode is adopted to obtain methyl acetate with purity of over 99.90%, so that the problem that light component impurities such as acetaldehyde, acetone and the like with about 0.1% in the traditional process cannot be removed is solved.
This prior art has the following disadvantages: the loss of methyl acetate is severe, and the purity of methyl acetate is not high enough.
Disclosure of Invention
In one aspect, the invention provides refined methyl acetate which reduces the loss rate of methyl acetate and improves the purity of refined methyl acetate, wherein ethylene glycol is less than or equal to 0.0010%, methyl acetate is more than or equal to 99.98%, and the methyl acetate is a byproduct in the production of polyvinyl alcohol.
Further, the methanol is less than or equal to 0.0046 percent, the acetone is less than or equal to 0.0033 percent, and the acetaldehyde is less than or equal to 0.0063 percent.
Further, the moisture is less than or equal to 0.0076%; the acidity is less than or equal to 0.001 percent, calculated by acetic acid; vinyl acetate < 0.0001%.
In a second aspect, the invention provides a byproduct refined methyl acetate production system in PVA production, which comprises a first rectifying tower for extracting and rectifying crude methyl acetate, a second rectifying tower for separating extractant and a third rectifying tower for refining methyl acetate; the device also comprises a fourth rectifying tower for refining the methyl acetate, a fifth rectifying tower for evaporating and purifying the extractant, a sixth rectifying tower for rectifying the crude methyl acetate and an extractant middle tank for storing transition; the third rectifying tower is connected with a sixth rectifying tower, and the sixth rectifying tower is connected with a fourth rectifying tower.
Further, the mixed liquor distillate outlet of the third rectifying tower is respectively connected with the feed inlet of the first rectifying tower and the feed inlet of the sixth rectifying tower.
Further, the mixed liquor distillate outlet of the third rectifying tower is positioned at the top of the third rectifying tower.
Further, the mixed liquor distillation port of the sixth rectifying tower is respectively connected with the reflux port of the sixth rectifying tower and the feed port of the fourth rectifying tower, and the mixed liquor distillation port of the sixth rectifying tower is positioned at the top of the sixth rectifying tower.
Further, a methyl acetate outlet of the sixth rectifying tower is connected with a distillation notch of the third rectifying tower; and a methyl acetate outlet of the sixth rectifying tower is positioned at the bottom of the sixth rectifying tower.
In a third aspect, the invention provides a production process for refining methyl acetate by a byproduct in PVA production, wherein a part of mixed liquid of methanol, acetaldehyde, acetone and methyl acetate with the concentration of more than 98.3% distilled from a mixed liquid distillate outlet at the top of a third rectifying tower flows back into a first rectifying tower, and a part of mixed liquid flows into a sixth rectifying tower for rectification;
After rectifying in a sixth rectifying tower, the obtained methyl acetate flows back into a third rectifying tower from the bottom of the tower; feeding the mixture of methyl acetate, acetaldehyde and acetone into a fourth rectifying tower for rectification;
rectifying in a fourth rectifying tower to obtain light component with acetaldehyde content over 90%; methyl acetate flows back into the sixth rectifying tower from the bottom.
Further, the methyl acetate rectified by the sixth rectifying tower flows back into the third rectifying tower from a methyl acetate outlet of a tank at the bottom of the tower through a distillate notch at the upper part of the third rectifying tower.
The invention has the following beneficial effects:
According to the invention, crude methyl acetate recovered from alcoholysis waste liquid is used as a raw material, ethylene glycol is used as an extractant, and a multi-tower rectification mode is adopted, so that refined methyl acetate with purity of more than 99.98% is obtained, and the loss rate of methyl acetate is reduced.
The invention reduces the content of methyl ester in light component impurities such as acetaldehyde, acetone and the like, reduces the processing capacity of a subsequent light component system, and improves the yield of refined methyl ester.
The invention can recycle the ethylene glycol for a long time, can continuously purify the ethylene glycol, and ensures the effect of extracting the methyl acetate from the recycled ethylene glycol.
The process of the invention is mature and has realized industrialized production.
Drawings
FIG. 1 is a schematic representation of methyl acetate example 1 of the present invention.
FIG. 2 is a schematic representation of comparative example 1 of methyl acetate according to the present invention.
Detailed Description
The examples are presented for better illustration of the present invention, but are not intended to limit the scope of the present invention to the examples. Those skilled in the art will appreciate that various modifications and adaptations of the embodiments described above are possible in light of the above teachings and are intended to be within the scope of the invention.
1. Definition of the definition
1) The extractant comprises: chemical agents capable of forming an organic phase-soluble extract with the extracted material.
2. Detection method
Routine chemical analysis and chromatographic detection
Example 1
A device for purifying a refined methyl acetate extractant comprises a first rectifying tower 1 for extracting and rectifying crude methyl acetate, a second rectifying tower 2 for separating the extractant and a third rectifying tower 3 for refining methyl acetate; the device also comprises a fourth rectifying tower 4 for rectifying the crude methyl acetate, a fifth rectifying tower 5 for evaporating and purifying the extractant, a sixth rectifying tower 6 for refining the methyl acetate and an extractant intermediate tank 7 for storing transition; the third rectifying tower 3 is connected with a sixth rectifying tower 6, and the sixth rectifying tower 6 is connected with a fourth rectifying tower 4; the first rectifying tower 1 is respectively connected with the second rectifying tower 2, the third rectifying tower 3 and the extractant intermediate tank 7; the extractant intermediate tank 7 is respectively connected with the first rectifying tower 1, the second rectifying tower 2 and the fifth rectifying tower 5; the second rectifying tower 2 is connected with the fifth rectifying tower 5; the third rectifying tower 3 is respectively connected with the first rectifying tower 1 and the sixth rectifying tower 6, the sixth rectifying tower 6 is positioned between the third rectifying tower 3 and the fourth rectifying tower 4, the third rectifying tower is positioned between the first rectifying tower 1 and the sixth rectifying tower 6, the second rectifying tower 2 is positioned below the first rectifying tower 1, the left side of the fifth rectifying tower 5 and the lower part of the extractant middle groove.
The third rectifying tower 3 is connected with a sixth rectifying tower 6, and the sixth rectifying tower 6 is connected with a fourth rectifying tower 4; the mixed liquid distillate outlet at the top of the third rectifying tower 3 is respectively connected with a feed inlet at the middle lower part of the first rectifying tower 1 and a feed inlet at the middle part of the sixth rectifying tower 6;
The mixed liquid distillate outlet at the top of the sixth rectifying tower 6 is respectively connected with a reflux outlet at the upper part of the sixth rectifying tower 6 and a feed inlet at the middle part of the fourth rectifying tower 4; the outlet of the methyl acetate tank at the bottom of the sixth rectifying tower 6 is connected with a distillate notch at the upper part of the third rectifying tower 3; the light fractionation outlet at the top of the fourth rectifying tower 4 is connected with a reflux port at the upper part of the fourth rectifying tower 4; the sixth rectifying tower 6 is placed between the third rectifying tower 3 and the fourth rectifying tower.
The mixed liquid distillate outlet at the top of the sixth rectifying tower 6 is respectively connected with a reflux outlet at the upper part of the sixth rectifying tower 6 and a feed inlet at the middle part of the fourth rectifying tower 4; the outlet of the methyl acetate tank at the bottom of the sixth rectifying tower 6 is connected with a distillate notch at the upper part of the third rectifying tower 3; the light fractionation outlet at the top of the fourth rectifying tower 4 is connected with a reflux port at the upper part of the fourth rectifying tower 4; the sixth rectifying tower 6 is placed between the third rectifying tower 3 and the fourth rectifying tower 4.
The mixture port at the bottom of the first rectifying tower 1 is connected with the feeding port in the middle of the second rectifying tower 2;
Methyl acetate and methanol distilled from the top of the second rectifying tower 2 are fed into a raw liquid tank, and a glycol discharge port at the bottom of the raw liquid tank is respectively connected with a feed inlet at the upper part of one side of an extractant middle tank 7 and a feed inlet at the middle part of the fifth rectifying tower 5;
The fifth rectifying tower 5 is respectively connected with the second rectifying tower 2 and the extractant intermediate tank 7, and the second rectifying tower 2 is also connected with the extractant intermediate tank 7; the first rectifying tower 1 is respectively connected with the second rectifying tower 2 and the third rectifying tower 3. The solid-liquid mixture of the fifth rectifying tower 5 is barreled into a waste liquid from the bottom of the tower, and the glycol inlet at the top of the fifth rectifying tower 5 is respectively connected with the glycol reflux inlet at the upper part of the fifth rectifying tower 5 and the feeding inlet at the upper part of one side of the extractant middle tank 7.
A discharge port at the lower part of the other side of the extractant middle tank 7 is connected with an ethylene glycol reflux port at the upper part of the first rectifying tower 1, and a mixture distillation port at the top of the first rectifying tower 1 is respectively connected with a mixture distillation port at the upper part of the first rectifying tower 1 and a feed port at the middle part of the third rectifying tower 3; wherein, the mixture distillation inlet of the first rectifying tower 1 is positioned above the glycol reflux port of the first rectifying tower 1.
And (3) a tower top tank of the third rectifying tower 3 is used for outputting a methyl acetate product.
Example 2
A production process of methyl acetate comprises the following steps:
The crude methyl acetate in the first rectifying tower 1 is extracted and rectified, byproducts (crude methyl acetate) in the production of polyvinyl alcohol are taken as raw materials, and enter the first rectifying tower 1, and glycol is added for extraction and distillation. A mixture of methanol, methyl acetate and ethylene glycol is discharged from a mixture port at the bottom of the tower and is sent to a second rectifying tower 2 from a feed port for recovery; the mixture of methanol, methyl acetate, acetaldehyde and acetone is distilled from the distillation port of the mixture at the top of the tower, and is sent to a third rectifying tower 3 from a feed port to remove light components, so as to refine the methyl acetate.
Separating the extractant by a second rectifying tower 2, distilling the mixture of methanol, methyl acetate and ethylene glycol from the bottom tank of the first rectifying tower, and feeding the methyl acetate and the methanol to a raw liquid tank from the top of the tower; the glycol part discharged from the tower bottom tank is sent into an extractant intermediate tank 7 to be used as a circulating extractant, and part of the glycol part is sent into a fifth rectifying tower 5 to be evaporated.
Refining methyl acetate in the third rectifying tower 3, refining the distillate mixed liquor of the first rectifying tower 1, and obtaining qualified refined methyl acetate product with purity of more than 99.98% in a tank; and (3) feeding a part of the mixed solution containing methanol, acetaldehyde and acetone to the first rectifying tower 1 for circulation, and feeding the other part of the mixed solution to the sixth rectifying tower 6 for removing light components to refine the methyl acetate, wherein the methyl acetate is more than 98.3% of methyl acetate obtained by distillation at the top of the tower.
The fourth rectifying tower 4 is used for refining methyl acetate, methanol, acetaldehyde and acetone which are distilled off by the sixth rectifying tower 6 are rectified, light components of methanol, acetaldehyde (90 percent) and acetone are removed, and the mixture is used as an acetaldehyde product to be sent to other working procedures at 20L/h; and the tank is sent out of the sixth rectifying tower 6 to be distilled out of the tank.
And the fifth rectifying tower 5 evaporates and purifies the extractant, the glycol and the methanol sent from the second rectifying tower 2 are evaporated, the glycol distilled from the top of the tower is sent into the middle extractant tank 7, and then the glycol is sent into the first rectifying tower 1 from the middle extractant tank 7 to be used as the extractant for recycling, and the solid-liquid mixture discharged from the tower bottom tank is discharged periodically.
And rectifying the crude methyl acetate in the sixth rectifying tower 6, rectifying the methyl acetate, the acetaldehyde, the acetone and the methanol which are fed by the third rectifying tower 3, feeding the methyl acetate, the methanol, the acetaldehyde (20%) and the acetone which are distilled out from the top of the tower into the fourth rectifying tower 4 for rectification again, and feeding the purified methyl acetate out of the tower bottom tank into a distillation tank of the third rectifying tower 3.
Comparative example 1
The crude methyl acetate in the first rectifying tower 1 is extracted and rectified, byproducts (crude methyl acetate) in the production of polyvinyl alcohol are taken as raw materials, and enter the first rectifying tower 1D-48001 of methyl acetate, and ethylene glycol is added for extraction and distillation. The mixture of methanol, methyl acetate and glycol is discharged from the tower bottom tank and is sent to a second rectifying tower 2 for recovery; methanol, methyl acetate, acetaldehyde, acetone and the like are distilled out from the top of the tower and sent to a third rectifying tower 3 to remove light components.
Separating the extractant by the second rectifying tower 2, distilling the mixture of methanol, methyl acetate and ethylene glycol from the bottom tank of the first rectifying tower 1, and feeding the methyl acetate and the methanol at the top of the tower into a raw liquid tank; the glycol part discharged from the tower bottom tank is sent into an extractant intermediate tank 7 to be used as a circulating extractant, and part of the glycol part is sent into a fifth rectifying tower 5 to be evaporated.
Refining methyl acetate in the third rectifying tower 3, refining the distillate mixed liquor of the first rectifying tower 1, and obtaining qualified refined methyl acetate product with purity of more than 99.93 percent in a tank; the methyl acetate with the distillate of more than 98.3 percent and the mixed solution containing methanol, acetaldehyde and acetone with the concentration of 1.5t/h are sent to other working procedures for treatment.
And the fifth rectifying tower 5 evaporates and purifies the extractant, the glycol and the methanol sent from the second rectifying tower 2 are evaporated, the glycol distilled from the top of the tower is sent into the middle extractant tank 7, and then the glycol is sent into the first rectifying tower 1 from the middle extractant tank 7 to be used as the extractant for recycling, and the solid-liquid mixture discharged from the tower bottom tank is discharged periodically.
| Detecting items | Test results |
| Moisture, percent | 0.0071 |
| Acidity (in acetic acid)%, percent | 0.001 |
| Acetaldehyde% | 0.0035 |
| Methanol,% | 0.0046 |
| Acetone,% | 0.0033 |
| Vinyl acetate% | ＜0.0001 |
| Ethylene glycol, percent | 0.0004 |
| Methyl acetate% | 99.98 |
Furthermore, it should be understood that although the present disclosure describes embodiments, not every embodiment is provided with a separate embodiment, and that this description is provided for clarity only, and that the disclosure is not limited to the embodiments described in detail below, and that the embodiments described in the examples may be combined as appropriate to form other embodiments that will be apparent to those skilled in the art.
Claims (9)
1. A purified methyl acetate, characterized in that: wherein the content of glycol is less than or equal to 0.0010 percent, and the content of methyl acetate is more than or equal to 99.98 percent, and the methyl acetate is a byproduct in the production of polyvinyl alcohol.
2. The refined methyl acetate of claim 1, wherein: wherein the content of methanol is less than or equal to 0.0046 percent, the content of acetone is less than or equal to 0.0033 percent, and the content of acetaldehyde is less than or equal to 0.0063 percent.
3. The purified methyl acetate according to claim 1 or 2, characterized in that: the water content is less than or equal to 0.0076%; the acidity is less than or equal to 0.001 percent, calculated by acetic acid; vinyl acetate < 0.0001%.
4. A production system for refining methyl acetate according to any one of claims 1 to 3, comprising a first rectifying column (1) for extractive rectification of crude methyl acetate, a second rectifying column (2) for separating extractant, and a third rectifying column (3) for refining methyl acetate; the method is characterized in that: the device also comprises a fourth rectifying tower (4) for refining the methyl acetate, a fifth rectifying tower (5) for evaporating and purifying the extractant, a sixth rectifying tower (6) for rectifying the crude methyl acetate and an extractant intermediate tank (7) for storing transition; the third rectifying tower (3) is connected with a sixth rectifying tower (6), and the sixth rectifying tower (4) is connected with a fourth rectifying tower (4).
5. The production system for refining methyl acetate according to claim 4, wherein: the mixed liquor distillation port of the third rectifying tower (3) is respectively connected with the feed port of the first rectifying tower (1) and the feed port of the sixth rectifying tower (6); the mixed liquor distillation port of the third rectifying tower (3) is positioned at the top of the third rectifying tower (3).
6. The production system for refining methyl acetate according to claim 4 or 5, wherein: the mixed liquid distillate outlet of the sixth rectifying tower (6) is respectively connected with the reflux outlet of the sixth rectifying tower (6) and the feed inlet of the fourth rectifying tower (4), and the mixed liquid distillate outlet of the sixth rectifying tower (6) is positioned at the top of the sixth rectifying tower (6).
7. The production system for refining methyl acetate according to claim 4, 5 or 6, wherein: the methyl acetate outlet of the sixth rectifying tower (6) is connected with the distillation notch of the third rectifying tower (3); the methyl acetate outlet of the sixth rectifying tower (6) is positioned at the bottom of the sixth rectifying tower (6).
8. A process for refining methyl acetate using the production system according to any one of claims 4 to 7, characterized in that: a part of the mixed liquor of methanol, acetaldehyde, acetone and methyl acetate which are distilled out from a mixed liquor distillation port at the top of the third rectifying tower (3) flows back into the first rectifying tower (1), and the other part flows into the sixth rectifying tower (6) for rectification;
After rectification in a sixth rectifying tower (6), the obtained methyl acetate flows back into a third rectifying tower (3) from the bottom of the tower; feeding the mixture of methyl acetate, acetaldehyde and acetone into a fourth rectifying tower (4) for rectification;
After being rectified by a fourth rectifying tower (4), the light component is separated from the top of the tower, wherein the acetaldehyde content is more than or equal to 90 percent; methyl acetate flows back into the sixth rectifying tower (6) from the bottom of the tower.
9. The production process according to claim 8, characterized in that: methyl acetate rectified by the sixth rectifying tower (6) flows back into the third rectifying tower (3) from a methyl acetate outlet of a tank at the bottom of the tower through a distillation notch at the upper part of the third rectifying tower (3).
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211552367.5A CN118146092A (en) | 2022-12-05 | 2022-12-05 | Refined methyl acetate and production process and production system thereof |
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| CN202211552367.5A CN118146092A (en) | 2022-12-05 | 2022-12-05 | Refined methyl acetate and production process and production system thereof |
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