CN108675932A - A kind of purification process of ethyl acetate - Google Patents
A kind of purification process of ethyl acetate Download PDFInfo
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- CN108675932A CN108675932A CN201810908125.2A CN201810908125A CN108675932A CN 108675932 A CN108675932 A CN 108675932A CN 201810908125 A CN201810908125 A CN 201810908125A CN 108675932 A CN108675932 A CN 108675932A
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- ethyl acetate
- purification process
- ion exchange
- exchange resin
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/48—Separation; Purification; Stabilisation; Use of additives
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/48—Separation; Purification; Stabilisation; Use of additives
- C07C67/52—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation
- C07C67/54—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation by distillation
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/48—Separation; Purification; Stabilisation; Use of additives
- C07C67/56—Separation; Purification; Stabilisation; Use of additives by solid-liquid treatment; by chemisorption
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- Crystallography & Structural Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The invention discloses a kind of purification process of ethyl acetate.It is adsorbed, is then dried by 13X molecular sieves to go to remove water using strong-acid ion exchange resin successively first in the purification process of the purification process present invention；Then, it is respectively 1 using by mass ratio：0.4~0.8：The extracting rectifying that 0.6~1.2 isopropanol, THF, propylene glycol are formed separates ethyl acetate from the ternary azeotropic objects system of ethyl acetate water-ethanol, and micro-filtration has filtered the inorganic agent used mixed in first three step.This purification process is easy to operate, and the product of purifying has preferable purity and high income.
Description
Technical field
The present invention relates to the technical field of ethyl acetate purification more particularly to a kind of purification process of ethyl acetate.
Background technology
Ethyl acetate is colourless transparent liquid, there is fruit perfume, volatile, to air-sensitive, can absorb water and divide, moisture can make
It slowly decomposes and is in acidity.Can be miscible with chloroform, ethyl alcohol, acetone and ether, it is dissolved in water (lOml/ml).Certain gold can be dissolved
Belong to salt (such as chlorination file, Cobalt Chloride, zinc chloride, iron chloride).Relative density is 0. 902, and fusing point is -83 DEG C, and boiling point is
77 DEG C, index of refraction is 1. 3719, and flash-point is 7. 2 DEG C (opening cup).Inflammable, steam can form explosive mixture with air.
It is irritant, median lethal dose (rat, oral) 11. 3ml/kg.As extractant, many chemical combination can be extracted from aqueous solution
Object (phosphorus, tungsten, arsenic, brill).It can be used as the standard substance of correction thermometer when detaching carbohydrate.Examine and determine tin, gold, iron, mercury, oxidant and
Platinum.Measure tin, boron, gold, iron, aluminium, platinum, potassium and shop.For Biochemical Research, protein sequencing, pesticide residue analysis.With
In organic synthesis, fragrance manufacture, white spirit mixing fragrance, artificial essence, ethyl cellulose, nitrocellulose, match fine jade can be done
Fine jade, varnish, coating, artificial leather, malthoid, staple fibre, printing ink etc..Also it can make the binder of olivet, drug and have
The extractant of machine acid and the raw material of fruity perfume.
Since major impurity is the gas chromatographies such as water, acetic acid, alcohol in industrial goods ethyl acetate.It usually carries in the prior art
Pure method is to obtain the ethyl acetate of purifying after being first dehydrated with dead plaster using air-distillation.Due to contained by ethyl acetate
Impurity be easy to ethyl acetate formed binary or ternary azeotrope, thus using air-distillation be difficult to by binary or ternary perseverance
Isolated ethyl acetate in object is boiled, causes product purity high.Chinese patent CN 1803757A disclose a kind of ethyl acetate
Method of purification, this method by temperature be 85~90 DEG C and containing water, acetic acid, ethyl alcohol thick acetic acid second extremely in the middle part of the rectifying column into
Enter in tower, forms ethyl alcohol, water and ethyl ester ternary azeotrope；It obtains containing ethyl alcohol, water and lacks in tower top after ternary azeotrope rectifying
The hair oil of ethyl acetate is measured, bottom of tower obtains the Liquid Residue containing acetic acid, ethyl acetate is obtained in tower；Liquid Residue is arranged from bottom of tower
Go out;Hair oil is extracted out from tower top, after condensation, split-phase processing is carried out, obtains water and oil phase, water is discharged, oil phase reflux in part is returned
Stream is than being 6~11:1, the recycling of remaining oil phase；The ethyl acetate obtained in tower is cooled down, partial reflux, reflux ratio is 1~5:
1, remaining ethyl acetate is the final finished product obtained.Although this method is more obtained by the above method, purity is higher, and operation is more multiple
Miscellaneous, product purity and yield are difficult to reach the high requirement of such as scientific research rank.
Invention content
In view of this, the present invention provides a kind of purification process of ethyl acetate easy to operate, obtained through the purification process
Purified product purity is higher and yield is larger.
A kind of purification process of ethyl acetate, includes the following steps：
（1）Pending thick ethyl acetate is set to pass through strong-acid ion exchange resin；
（2）It will be through step（1）Ethyl acetate pass through 13X molecular sieves；
（3）It will be through step（2）Ethyl acetate and extractant merging extracting rectifying device in carry out the processing of extracting rectifying, it is described
It is respectively 1 that extractant, which is by mass ratio,：0.4~0.8：The mixed liquor that 0.6~1.2 isopropanol, THF, propylene glycol are formed；
（4）It will be through step（3）Ethyl acetate carry out ultrafiltration.
In this purification process, it can be used by the form of strong-acid ion exchange resin and exchanged filled with strong acidic ion
The ion exchange column of resin material can directly buy the product sold.It is of course possible to by strong-acid ion exchange resin material
It is paved on adsorbent bed with one or more layers.
Strong-acid ion exchange resin is to provide hydrionic resin.Strong-acid ion exchange resin is preferred but is not limited to
Sulphur acid-exchange resin, if without the requirement for exchanging effect, it is also possible to other strong-acid ion exchange resins such as sulfuric acid
Type ion exchange resin substitutes.It can be used as the regeneration to above-mentioned strong-acid ion exchange resin well known in the art
Method.Flow velocity by strong-acid ion exchange resin is preferably 50~100mL/min.Effect shadow of the speed of flow velocity to absorption
Sound is not notable.
13X molecular sieves refer to also being sodium X-type molecular sieve, are alkali metal aluminosilicates, have certain alkalinity, belong to a kind of
Solid base, chemical formula Na2O· A12O3·2.45SiO2·6.0H2O, for adsorbing water impurity in the solution of the present invention,
Reach the purpose of drying.Adsorbent bed may be used by way of 13X molecular sieves, i.e., it is 13X is molecular sieve filled in adsorbent bed,
Material to be operated is set to flow through adsorbent bed.In the case where equipment does not allow, also directly 13X molecular sieves can be impregnated in pending
Material in, and simultaneously by stirring complete this by process, finally filter out 13X molecular sieve solids.In this kind of mode
Under basis, the dosage of 13X molecular sieves is generally 0.03~0.06（On the basis of the quality of thick ethyl acetate is 1）It is advisable.
Compared with the conventional distillation for being not added with extractant, extracting rectifying complex method of the present invention can significantly improve the effect of rectifying
Fruit.In addition in extracting rectifying device（Extractive distillation column）Outside the extractant that conditional circulates, other operations of extracting rectifying
Process is substantially identical as common conventional distillation.The composition of extractive distillation column is in addition to including the portion for adding or recycling for extractant
Exceptionally, other to be same as general rectifying column.Extractive distillation column disclosed in the prior art is commercially available suitable for this hair
It is bright.The mode of extracting rectifying preferably but not limited to hereinafter, i.e. extractant from the top of extractive distillation column be added, rectifying to be extracted
Ethyl acetate raw material from bottom of tower be added, then can 85~90 DEG C according to reflux ratio be 10:After 5~8 1~2h of reflux, go
Except front-end volatiles, rectifying is continued with the flow velocity of 20~30mL/min.
Extractant is 1：0.4~0.8：The mixed liquor that 0.6~1.2 isopropanol, THF, propylene glycol are formed.The extractant
With lower ethyl alcohol to the relative volatility of ethyl acetate.Ethyl alcohol is to weigh ethyl alcohol from second to the relative volatility of ethyl acetate
The measurement separated in acetoacetic ester, it is however generally that, value is lower, illustrates that ethyl alcohol is easier from ethyl acetate and alcohol mixture
Separation.
Ultrafiltration filter can remove the above-mentioned particle mixed after strong-acid ion exchange resin and the processing of 13X molecular sieves.It is micro-
Filter is carried out using commercially available ultrafiltration membrane.Microfiltration membranes are preferred but are not limited to be not more than using aperture 0.05 μm of Hollow Fiber Ultrafiltration
Film.It is many in view of the manufacturer and model of commercially available supermembrane, no longer enumerated here.
Term " thick ethyl acetate " refers to the ethyl acetate suitable for raw material of industry purity, to be purified employed in the present invention
Ethyl acetate be purity be about 98wt%.
As used herein, above-mentioned term：
"one", "an" and " described " be used interchangeably and refer to one or more.
"and/or" is used to indicate that one of illustrated situation or both may to occur, for example, A and/or B includes (A
And B) and (A or B).
In addition, the range stated herein by endpoint includes all numerical value for being included within the scope of this（For example, 1 to 10 packet
Include 1.4,1.9,2.33,5.75,9.98 etc.）.
In addition, the statement of "at least one" herein includes one or more all numbers（For example, at least two, at least
4, at least six, at least eight, at least ten, at least 25, at least 50, at least 100 etc.）.
It is adsorbed successively using strong-acid ion exchange resin first in the purification process of the present invention, then passes through 13X molecules
Sieve is dried to go to remove water；Then, it is respectively 1 using by mass ratio：0.4~0.8：0.6~1.2 isopropanol, THF, third
The extracting rectifying that glycol is formed separates ethyl acetate from the ternary azeotropic objects system of ethyl acetate-water-ethanol, micro-
The inorganic agent used mixed in first three step is filtered.This purification process is easy to operate, and the product of purifying has preferably
Purity and high income.
Specific implementation mode
The technical solution further illustrated the present invention with reference to embodiment.
Embodiment 1
By 1000 g industry level ethyl acetates（Purity 98%）With the flow velocity of 50mL/min by being equipped with sulfonic acid type ion exchange column.
Then, to by sulfonic acid type ion exchange column liquid in input quality be 40 g 13X molecular sieves to be adsorbed, then filter
Go out liquid.Then this is filtered out into liquid and 600g extractants（It is respectively 1 by mass ratio：0.5：1.2 isopropanol, THF, the third two
Alcohol is formed）Be placed in extractive distillation column in, 90 DEG C according to reflux ratio be 10:After 5 reflux 1h, front-end volatiles are removed, with 20mL/
The flow velocity of min continues rectifying.It finally uses hollow fiber ultrafiltration membrane of the aperture more than 0.5 micron to carry out micro-filtration, obtains purifying second
Acetoacetic ester.The yield of this example ethyl acetate is 94.1%, and purity is 99.91% after tested.
Embodiment 2
By 1000 g industry level ethyl acetates（Purity 98%）With the flow velocity of 100mL/min by being equipped with sulfonic acid type ion exchange column.
Then, to by sulfonic acid type ion exchange column liquid in input quality be 80 g 13X molecular sieves to be adsorbed, then filter
Go out liquid.Then this is filtered out into liquid and 3000g extractants（It is respectively 1 by mass ratio：0.4：0.6 isopropanol, THF, third
Glycol is formed）Be placed in extractive distillation column in, 85 DEG C according to reflux ratio be 10:After 8 reflux 2h, front-end volatiles are removed, with 30mL/
The flow velocity of min continues rectifying.It finally uses hollow fiber ultrafiltration membrane of the aperture more than 0.5 micron to carry out micro-filtration, obtains purifying second
Acetoacetic ester.The yield that this example is collected into ethyl acetate is 94.8%, and purity is 99.93% after tested.
Embodiment 3
By 1000 g industry level ethyl acetates（Purity 98%）With the flow velocity of 75mL/min by being equipped with sulfonic acid type ion exchange column.
Then, to by sulfonic acid type ion exchange column liquid in input quality be 60 g 13X molecular sieves to be adsorbed, then filter
Go out liquid.Then this is filtered out into liquid and 1800g extractants（It is respectively 1 by mass ratio： 0.8：1.2 isopropanol, THF,
Propylene glycol is formed）Be placed in extractive distillation column in, 87 DEG C according to reflux ratio be 10:After 8 reflux 1.5h, front-end volatiles are removed, with
The flow velocity of 25mL/min continues rectifying.It finally uses hollow fiber ultrafiltration membrane of the aperture more than 0.5 micron to carry out micro-filtration, obtains pure
Change ethyl acetate.The yield that this example is collected into ethyl acetate is 94.9%, and purity is 99.94% after tested.
Embodiment 4
By 1000 g industry level ethyl acetates（Purity 98%）With the flow velocity of 75mL/min by being equipped with sulfonic acid type ion exchange column.
Then, to by sulfonic acid type ion exchange column liquid in input quality be 60 g 13X molecular sieves to be adsorbed, then filter
Go out liquid.Then this is filtered out into liquid and 3000g extractants（It is respectively 1 by mass ratio：0.55：0.95 isopropanol, THF,
Propylene glycol is formed）Be placed in extractive distillation column in, 87 DEG C according to reflux ratio be 10:After 8 reflux 1.5h, front-end volatiles are removed, with
The flow velocity of 30mL/min continues rectifying.It finally uses hollow fiber ultrafiltration membrane of the aperture more than 0.5 micron to carry out micro-filtration, obtains pure
Change ethyl acetate.This example is collected into 9330 g of ethyl acetate, and yield 93.3%, purity is 99.96% after tested.
Embodiment 5
By 1000 g industry level ethyl acetates（Purity 98%）With the flow velocity of 100mL/min by being equipped with sulfonic acid type ion exchange column.
Then, to by sulfonic acid type ion exchange column liquid in input quality be 80 g 13X molecular sieves to be adsorbed, then filter
Go out liquid.Then this is filtered out into liquid and 1800g extractants（It is respectively 1 by mass ratio：0.55：0.95 isopropanol, THF,
Propylene glycol is formed）Be placed in extractive distillation column in, 85 DEG C according to reflux ratio be 10:After 8 reflux 2h, front-end volatiles are removed, with
The flow velocity of 30mL/min continues rectifying.It finally uses hollow fiber ultrafiltration membrane of the aperture more than 0.5 micron to carry out micro-filtration, obtains pure
Change ethyl acetate.The yield that this example is collected into ethyl acetate is 95.2%, and purity is 99.98% after tested.
Comparative example
In this example, extractant 1：1：1 glycerine, DMSO, propylene glycol are formed, the other the same as in Example 5.This example is collected into second
The yield of acetoacetic ester is 92.8%, and purity is 99.28% after tested.
Since the numberical range of each technological parameter involved in the present invention can not possibly all embody in the above-described embodiments,
As long as but those skilled in the art's envisioned any numerical value fallen into the above-mentioned numberical range completely can implement this
Invention also includes the arbitrary combination of occurrence in several numberical ranges certainly.Herein, for length the considerations of, be omitted to
Go out the embodiment of occurrence in certain one or more numberical range, this disclosure for being not to be construed as technical scheme of the present invention is not filled
Point.
Applicant states that the present invention illustrates detailed process equipment and the technological process of the present invention by above-described embodiment,
But the invention is not limited in above-mentioned detailed process equipment and technological processes, that is, it is above-mentioned detailed not mean that the present invention has to rely on
Process equipment and technological process could be implemented.Person of ordinary skill in the field it will be clearly understood that any improvement in the present invention,
The addition of equivalence replacement and auxiliary element to each raw material of product of the present invention, the selection etc. of concrete mode all fall within the present invention's
Within protection domain and the open scope.
Claims (7)
1. a kind of purification process of ethyl acetate, which is characterized in that include the following steps：
（1）Pending thick ethyl acetate is set to pass through strong-acid ion exchange resin；
（2）It will be through step（1）Ethyl acetate pass through 13X molecular sieves；
（3）It will be through step（2）Ethyl acetate and extractant merging extracting rectifying device in carry out the processing of extracting rectifying, it is described
It is respectively 1 that extractant, which is by mass ratio,：0.4~0.8：The mixed liquor that 0.6~1.2 isopropanol, THF, propylene glycol are formed；
（4）It will be through step（3）Ethyl acetate carry out ultrafiltration.
2. purification process according to claim 1, which is characterized in that the flow velocity by strong-acid ion exchange resin
For 50~100mL/min.
3. purification process according to claim 1, which is characterized in that the strong-acid ion exchange resin be sulfonic acid from
Sub-exchange resin.
4. purification process according to claim 1, which is characterized in that by the quality of thick ethyl acetate be the 13X point in terms of 1
The dosage of son sieve is 0.03~0.06.
5. purification process according to claim 1, which is characterized in that by the quality of thick ethyl acetate be 1 in terms of the extraction
The dosage of agent is 0.6~3.
6. purification process according to claim 1, which is characterized in that the extracting rectifying specifically, rectifying to be extracted
Ethyl acetate 85~90 DEG C according to reflux ratio be 10:After 5~8 1~2h of reflux, front-end volatiles are removed, with 20~30mL/min
Flow velocity continue rectifying.
7. purification process according to claim 1, which is characterized in that the ultrafiltration is not more than using aperture in 0.05 μm
Fibre ultrafiltration film.
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| CN201810908125.2A CN108675932A (en) | 2018-08-10 | 2018-08-10 | A kind of purification process of ethyl acetate |
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| CN201810908125.2A CN108675932A (en) | 2018-08-10 | 2018-08-10 | A kind of purification process of ethyl acetate |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109704959A (en) * | 2018-12-21 | 2019-05-03 | 江门谦信化工发展有限公司 | A kind of industrialized preparing process of electronic grade acetic acid ester solvent |
| CN112299999A (en) * | 2020-11-13 | 2021-02-02 | 南京化学试剂股份有限公司 | Refining method of high-purity ethyl acetate |
| CN115108910A (en) * | 2022-08-09 | 2022-09-27 | 珠海谦信新材料有限公司 | Synthesis and heat coupling process of ethyl acetate |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2000044696A1 (en) * | 1999-01-28 | 2000-08-03 | Izak Nieuwoudt | Separation of ethanol and ethyl acetate from mixtures thereof by extractive distillation |
| CN104693028A (en) * | 2015-03-31 | 2015-06-10 | 太仓沪试试剂有限公司 | Purification method of ethyl acetate |
-
2018
- 2018-08-10 CN CN201810908125.2A patent/CN108675932A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2000044696A1 (en) * | 1999-01-28 | 2000-08-03 | Izak Nieuwoudt | Separation of ethanol and ethyl acetate from mixtures thereof by extractive distillation |
| CN104693028A (en) * | 2015-03-31 | 2015-06-10 | 太仓沪试试剂有限公司 | Purification method of ethyl acetate |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109704959A (en) * | 2018-12-21 | 2019-05-03 | 江门谦信化工发展有限公司 | A kind of industrialized preparing process of electronic grade acetic acid ester solvent |
| CN112299999A (en) * | 2020-11-13 | 2021-02-02 | 南京化学试剂股份有限公司 | Refining method of high-purity ethyl acetate |
| CN112299999B (en) * | 2020-11-13 | 2021-07-13 | 南京化学试剂股份有限公司 | Refining method of high-purity ethyl acetate |
| CN115108910A (en) * | 2022-08-09 | 2022-09-27 | 珠海谦信新材料有限公司 | Synthesis and heat coupling process of ethyl acetate |
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Application publication date: 20181019 |