CN1163467C - Method for preparing dihydric alcohol ester by using reactive distillation process - Google Patents
Method for preparing dihydric alcohol ester by using reactive distillation process Download PDFInfo
- Publication number
- CN1163467C CN1163467C CNB001037471A CN00103747A CN1163467C CN 1163467 C CN1163467 C CN 1163467C CN B001037471 A CNB001037471 A CN B001037471A CN 00103747 A CN00103747 A CN 00103747A CN 1163467 C CN1163467 C CN 1163467C
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- Prior art keywords
- glycol ether
- distillation tower
- carboxylic acid
- alcohol esters
- reaction
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/24—Preparation of carboxylic acid esters by reacting carboxylic acids or derivatives thereof with a carbon-to-oxygen ether bond, e.g. acetal, tetrahydrofuran
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/10—Process efficiency
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/582—Recycling of unreacted starting or intermediate materials
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
Disclosed is a process for the preparation of glycol esters from glycol ethers and carboxylic acids in the presence of a strong acid cation exchange resin. The catalytic reaction is carried out in a first reactive distillation column at a pressure of 10 to 700 mbar, the temperature being maintained at 50 to 150 ℃. The reaction in the reactive distillation column separates the glycol ester and unreacted reactants. The glycol esters are withdrawn through the lower portion of the distillation column, and the unreacted reactants are directed to a second distillation column from which they are reused as a feedstock. The use of a solid catalyst does not require a procedure to separate the catalyst from the reaction. The use of a reactive distillation column to separate the product increases the conversion of glycol ether without being limited by the equilibrium in the first distillation column, greatly improving the productivity of glycol esters.
Description
Putting it briefly the present invention relates to utilize the reactive distillation process to prepare the method for binary alcohol esters (glycol ester), more particularly the present invention relates to prepare binary alcohol esters with strong-acid cation-exchange resin by glycol ether (glycol ether) and carboxylic acid.
Usually, glycol ether has very wide range of application as a kind of solvent.At paint, printing ink, tackiness agent, there are many application in aspects such as clean-out system.This useful solvent obtains by making glycol ether and carboxylic acid reaction and purified product.Extensive studies has been carried out in this reaction and purifying.
In U.S. Patent No. 2,618, in 973, glycol ether and carboxylic acid carry out addition reaction and obtain binary alcohol esters under the condition that Phenylsulfonic acid exists, and this binary alcohol esters is purified by a kind of azeotropic solvent hexanaphthene then.Because need product and used catalyst separating, and this azeotropic solvent of will purifying, so this method is very complicated.
U.S. Patent No. 5,202,463 have disclosed a kind of application of azeotropic solvent in purifying glycol ether and the resulting product of carboxylic acid reaction that is defined as methyl iso-butyl ketone (MIBK) (MIBK).
As mentioned above, use catalyzer (such as Phenylsulfonic acid) and azeotropic solvent to come to prepare the last handling process of binary alcohol esters requirement such as separating catalyst and azeotropic solvent from glycol ether and carboxylic acid.In addition, their use makes reaction process be difficult to operation, and can make reactant (glycol ether and carboxylic acid) and product (binary alcohol esters) loss.
The inventor has carried out research extensively and profoundly repeatedly to the preparation of binary alcohol esters, purpose is to use and a kind ofly is easy to handle and industrial favourable solid acid improves the turnover ratio of glycol ether, the strong acid cation resin that discovery has a polystyrene skeleton has very catalytic activity for the reaction between glycol ether and the carboxylic acid, and is easy to separate from reactive system.Reaction that also find to use reactive distillation tower that this catalyzer is housed can order about consumingly between glycol ether and the carboxylic acid is in addition carried out towards positive dirction, has greatly improved the productivity of binary alcohol esters.
Therefore, an object of the present invention is to overcome the problem that prior art runs into, and provide a kind of reactive distillation process of utilizing to prepare the method for binary alcohol esters by glycol ether and carboxylic acid, this method not only has high yield but also very simple.
The method for preparing binary alcohol esters by glycol ether and carboxylic acid according to the present invention can be finished above-mentioned purpose, this method comprises the steps: glycol ether and carboxylic acid mixed flow are added to first distillation tower that is filled with strong acid cation resin, glycol ether and carboxylic acid carry out reactive distillation and produce binary alcohol esters in this first distillation tower, never isolate binary alcohol esters in reactant that reacts and the water that is produced, this binary alcohol esters is discharged from the bottom of first distillation tower, and unreacted reactant and the water that the produced top by first distillation tower passes to second column; Make unreacted reactant separated from one another with the water that is produced in second column, water is removed, and unreacted reactant is reused to mixed flow.
Fig. 1 is the process flow sheet for preparing the binary alcohol esters method by the reactive distillation process according to of the present invention.
Fig. 2 is another process flow sheet for preparing the binary alcohol esters method by fixed-bed reactor and reactive distillation process according to of the present invention.
Below in conjunction with accompanying drawing the present invention is made more detailed description.
The invention is characterized in and use the reactive distillation tower that catalyzer is housed, prepare binary alcohol esters from glycol ether and carboxylic acid.Also can randomly before raw material is added to distillation tower, in fixed-bed reactor, make reactant glycol ether and carboxylic acid carry out pre-reaction, make its part be converted into binary alcohol esters, to improve reaction efficiency.
Referring to Fig. 1, this is according to the process flow sheet of the present invention by the preparation binary alcohol esters method of glycol ether and carboxylic acid.
Shown in this schema, the mixed flow of starting material glycol ether 1 and carboxylic acid 2 is directed into the reactive distillation tower C1 that the strong acid cation resin catalyzer is housed.In the product of the catalyzed reaction of tower C1, binary alcohol esters 4 is separated and guide to the bottom of tower by reactive distillation, and the residue of being made up of unreacted compound (glycol ether or carboxylic acid) and the water that is produced 5 is directed to the top of tower and passes to distillation tower C2, in distillation tower C2, unreacted compound 6 and water sepn also are recovered in the raw-material mixed flow, and 7 of moisture content are removed.
Referring to Fig. 2, this is another process flow sheet for preparing binary alcohol esters from glycol ether and carboxylic acid according to of the present invention.
Shown in this schema, the mixed flow of starting material glycol ether 1 and carboxylic acid 2 is directed into fixed-bed reactor R1, comprises a kind of strong-acid cation-exchange resin as catalyzer among these fixed-bed reactor R1.The reaction product 3 of coming out from these fixed-bed reactor R1 feeds to the reactive distillation tower C1 that same strong-acid cation-exchange resin catalyst is housed.In the catalytic reaction products of tower C1, binary alcohol esters 4 is separated and guide to the bottom of tower by reactive distillation, and the residue of being made up of unreacted compound (glycol ether or carboxylic acid) and the water that is produced 5 is directed to the top of tower and passes to distillation tower C2, in distillation tower C2, unreacted compound 6 and water sepn also are recovered in the raw-material mixed flow, and 7 of moisture content are removed.
As described, in reactive distillation column C1, randomly in fixed-bed reactor R1, under the catalyzer condition, pass through pre-treatment glycol ether 1, under the condition that strong-acid cation-exchange resin catalyst exists, be converted into binary alcohol esters.When this conversion part when implementing in fixed-bed reactor R1, can reduce the theoretical plate number in the reaction zone of reactive distillation tower C1, this is favourable economically.In addition, utilize reactive distillation tower C1 to come product separation, can improve the turnover ratio of glycol ether, make it not limited by the equilibrated among the fixed-bed reactor R1.
When strong-acid cation-exchange resin catalyst is packed distillation tower into, place it in the bag that makes with glass fibre, go down to avoid pressure decline and catalyzer slippage in the tower.This packed catalyzer is positioned in the middle part of distillation tower.The theoretical plate number in distillation column reaction district can change in the scope of 1-30 piece, depends on the kind of product and reactant.
The reaction pressure of distillation tower better is to remain on the 10-700 millibar.For example, when reaction pressure during less than 10 millibars, the turnover ratio of glycol ether can reduce.On the other hand, the reaction pressure in the distillation tower can cause the temperature in the reaction zone to raise when surpassing 700 millibars, and activity of such catalysts reduces.For the weight hourly space velocity in the distillation tower (WHSV) better is to be about 0.5-10 hour
-1For example, the weight hourly space velocity in distillation tower was less than 0.5 hour
-1The time can cause catalyzer too much with respect to handled reaction mass.On the other hand, when the weight hourly space velocity of reactant flow greater than 10 hours
-1The time. can obtain relatively poor glycol ether turnover ratio.
In fixed-bed reactor, the better condition of implementing reaction is: weight hourly space velocity is 1-10 hour
-1, temperature range is 50-150 ℃, pressure range is 10-300 pound/time
2(gauge pressure).
Be used for glycol ether of the present invention, be preferably propylene glycol monomethyl ether (propylene glycol methyl ether), but this do not limit the scope of the invention.Be used for carboxylic acid of the present invention and be preferably and be selected from acetate, but also be not limited to this compound.
As mentioned above, being used for catalyzer of the present invention is a kind of strong-acid cation-exchange resin with polystyrene skeleton.Usefully can be from Rohm ﹠amp; Haas obtains, commodity are called Amberlyst 16, Amberlyst 15, Ambeerlyst 35, and Amberlyst 150, Amberlyst XN-1005, Amberlyst XN-1010, and can obtain from DowChemical, commodity Dowex M-31 by name and Dowex M-32, but the present invention is not limited to these examples.
When the turnover ratio of the time limit of service of considering catalyzer and glycol ether, temperature of reaction better is to maintain 50-150 ℃, is more preferably 70-130 ℃.When temperature of reaction is lower than 50 ℃, can cause the reduction of glycol ether turnover ratio, and when temperature of reaction surpassed 150 ℃, activity of such catalysts can reduce.
When being directed into fixed-bed reactor R1 or reactive distillation tower C1, reactant is to be in admixture.In this mixture, when considering the turnover ratio of reactant, glycol ether is preferably 1 the mol ratio of carboxylic acid: 1-10 to 1-10: 1, and take into account when considering product separation and turnover ratio, be more preferably at 1: 1 to 1: 10.
The present invention may be better understood with reference to following embodiment, and these embodiment are in order to illustrate rather than in order to limit the present invention.
Embodiment 1:
With mol ratio is that 1: 2 propylene glycol monomethyl ether and acetate mix.This mixture is directed in as shown in Figure 2 the fixed-bed reactor, in these fixed-bed reactor, has 60% propylene glycol monomethyl ether to be converted into acetate propylene glycol monomethyl ether ester.The reaction of these fixed-bed reactor is 6 hours in weight hourly space velocity then
-1Carry out under the condition, arrive distillation tower again, 300 grams are equipped with at its middle part can be from Rohm; Amberlyst 16. these distillation towers that Haas buys are at following conditional operation: its upper pressure maintains 400 millibars, and the temperature maintenance of its bottom is at 110 ℃.The reflux ratio on top is 6.
Gas chromatographic analysis shows that it is acetate propylene glycol monomethyl ether ester that 99.5% propylene glycol monomethyl ether feedstock conversion is arranged.
Embodiment 2:
With mol ratio is that 1: 2 propylene glycol monomethyl ether and acetate mix.This mixture is directed in the fixed-bed reactor, in these fixed-bed reactor, has 60% propylene glycol monomethyl ether to be converted into acetate propylene glycol monomethyl ether ester.The reaction of these fixed-bed reactor is 3 hours in weight hourly space velocity then
-1Carry out under the condition, arrive distillation tower again, 200 gram Amberlyst 16. these distillation towers are equipped with at following conditional operation in its middle part: its upper pressure maintains 400 millibars, and the reflux ratio on top is 8, and the temperature maintenance of its bottom is at 110 ℃.
Gas chromatographic analysis shows has 99% propylene glycol monomethyl ether to be converted into acetate propylene glycol monomethyl ether ester.
Comparative Examples 1:
200 gram Amberlyst 16 are seated in as in the same fixed-bed reactor of embodiment 1, are 4 o'clock with weight hourly space velocity
-1Be that 1: 8 the propylene glycol monomethyl ether and the mixture of acetate input in these fixed-bed reactor with mol ratio under the condition.During reaction, fixed-bed reactor 100 pounds/time
2Under the pressure of (gauge pressure), its temperature maintenance is at 110 ℃.
Gas chromatographic analysis shows only has 75% raw material propylene glycol monomethyl ether to be converted into acetate propylene glycol monomethyl ether ester.
Owing to can reach balance between reaction of in closed system, being carried out and the backward reaction, use fixed-bed reactor will cause low-conversion like this separately.In addition, because a large amount of unreacted reactants of low-conversion need further to separate, make the process complexity and reduced productivity.
Can obviously see by the foregoing description: according to method of the present invention can use glycol ether and acetate with 99% or higher productive rate prepare binary alcohol esters.This productive rate even better than the resulting productive rate of following traditional method.In this traditional method, only use fixed-bed reactor, and be designed so that the mol ratio of reactant is so big, so that molecular balance tends to positive dirction.
The present invention narrates in the mode of explanation, should be appreciated that used term is for the present invention being described rather than being used to limit the present invention.Can do many improvement and variation to the present invention according to above-mentioned announcement.Therefore, should be appreciated that, can use the mode different to implement the present invention within the scope of the appended claims with the concrete mode of narrating.
Claims (6)
1. one kind prepares the method for binary alcohol esters by glycol ether and carboxylic acid, and this method comprises the steps:
Glycol ether and carboxylic acid mixed flow are inputed in first distillation tower that is filled with strong-acid cation-exchange resin, described first distillation tower has following reaction conditions: temperature of reaction is 50-150 ℃, weight hourly space velocity is 0.5-10 hour-1, and reaction pressure is the 10-700 millibar;
Make described glycol ether and described carboxylic acid in described first distillation tower, carry out reactive distillation, produce binary alcohol esters;
From unreacted reactant and the water that produced, isolate described binary alcohol esters, described binary alcohol esters takes out by the bottom of described first distillation tower, and described unreacted reactant and the water that is produced then enter second column by the top of described first distillation tower;
With described unreacted reactant and the water sepn that is produced, after water was removed, described unreacted reactant returns in the described mixed flow to be reused in second column.
2. the method for claim 1, its feature is that also described glycol ether is a methyl proxitol.
3. the method for claim 1, its feature is that also described carboxylic acid is an acetate.
4. the method for claim 1, its feature is that also the theoretical plate number of described first distillation tower is the 1-30 piece.
5. the method for claim 1, its feature are that also the mol ratio of glycol ether and carboxylic acid is 1 in the described mixed flow: 1-10 to 1-10: 1.
6. the method for claim 1, its feature is that also it comprised the steps: before described raw material input step, allowed described mixed flow be converted into binary alcohol esters to a certain extent in fixed-bed reactor in being filled with the fixed-bed reactor of strong-acid cation-exchange resin.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR998051 | 1999-03-11 | ||
| KR1019990008051A KR100286571B1 (en) | 1999-03-11 | 1999-03-11 | Method for preparing glycol ester using reactive distillation |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1268505A CN1268505A (en) | 2000-10-04 |
| CN1163467C true CN1163467C (en) | 2004-08-25 |
Family
ID=19576199
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB001037471A Expired - Lifetime CN1163467C (en) | 1999-03-11 | 2000-03-07 | Method for preparing dihydric alcohol ester by using reactive distillation process |
Country Status (4)
| Country | Link |
|---|---|
| JP (1) | JP2000264857A (en) |
| KR (1) | KR100286571B1 (en) |
| CN (1) | CN1163467C (en) |
| TW (1) | TW539668B (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100779521B1 (en) * | 2005-07-15 | 2007-11-28 | 주식회사 엘지화학 | Combined method of carboxylic acid and ester compound |
| CN102206153A (en) * | 2010-03-31 | 2011-10-05 | 东莞市同舟化工有限公司 | Method for continuously synthesizing propylene glycol methyl ether acetate |
| KR101134659B1 (en) | 2010-09-06 | 2012-04-09 | 이수화학 주식회사 | Preparation method of Propylene glycol monomethyl ether acetate |
| ES2636982T3 (en) * | 2013-05-03 | 2017-10-10 | Dow Global Technologies Llc | Procedure for reactions limited by equilibrium |
| KR101349106B1 (en) * | 2013-08-20 | 2014-01-08 | 에스케이종합화학 주식회사 | Method for preparing glycol ester using reactive distillation |
| CN104845735A (en) * | 2015-04-29 | 2015-08-19 | 四川银帆生物科技有限公司 | Two-time esterification technology in process of preparing fragrant liquid from liquor-making byproduct percolated yellow fermenting liquor |
| CN106187754B (en) * | 2015-05-06 | 2019-05-14 | 中国科学院大连化学物理研究所 | A kind of method of catalytic distillation production aromatic esters |
| WO2021172898A1 (en) * | 2020-02-26 | 2021-09-02 | 영남대학교 산학협력단 | Apparatus and method for manufacturing propylene glycol methyl ether acetate |
| KR102528573B1 (en) * | 2020-12-08 | 2023-05-04 | 주식회사 켐트로닉스 | Method for Producing Propylene Glycol Methyl Ether Acetate |
| KR102399263B1 (en) * | 2021-08-09 | 2022-05-17 | 에스케이머티리얼즈퍼포먼스 주식회사 | Process for the preparation of propylene glycol monomethyl ether acetate |
| KR102498772B1 (en) * | 2021-11-29 | 2023-02-10 | 주식회사 켐트로닉스 | Manufacturing method of ultra-high purity PGMEA |
-
1999
- 1999-03-11 KR KR1019990008051A patent/KR100286571B1/en not_active IP Right Cessation
-
2000
- 2000-03-07 CN CNB001037471A patent/CN1163467C/en not_active Expired - Lifetime
- 2000-03-07 JP JP2000062203A patent/JP2000264857A/en active Pending
- 2000-03-09 TW TW089104297A patent/TW539668B/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| JP2000264857A (en) | 2000-09-26 |
| KR100286571B1 (en) | 2001-03-15 |
| CN1268505A (en) | 2000-10-04 |
| TW539668B (en) | 2003-07-01 |
| KR20000060027A (en) | 2000-10-16 |
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