CN102690197A - Method for preparing acetic acid mixed butyl ester by continuous reaction and rectification - Google Patents

Method for preparing acetic acid mixed butyl ester by continuous reaction and rectification Download PDF

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Publication number
CN102690197A
CN102690197A CN2012101696745A CN201210169674A CN102690197A CN 102690197 A CN102690197 A CN 102690197A CN 2012101696745 A CN2012101696745 A CN 2012101696745A CN 201210169674 A CN201210169674 A CN 201210169674A CN 102690197 A CN102690197 A CN 102690197A
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acetic acid
butyl ester
tower
esterification
rectifying
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CN2012101696745A
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Inventor
赵楚榜
于冬娥
朱宏文
何文晖
吴长彩
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JIANGMEN HANDSOME CHEMICAL DEVELOPMENT Co Ltd
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JIANGMEN HANDSOME CHEMICAL DEVELOPMENT Co Ltd
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Abstract

The invention relates to a method for preparing acetic acid mixed butyl ester by continuous reaction and rectification. The method includes: acetic acid and mixed butanol are mixed and preheated according to molar ratio of 1:1, and temperatures of the mixed and preheated acetic acid and mixed butanol are increased after entering an esterification reactor and are reacted under catalysis of acid catalyst, a reaction product is performed initial gross separation in an esterification column in azeotrope form after being heated, a part of aqueous phase is performed reflux to the esterification column after a distillate at the top of the esterification column is performed condensation and phase separation, another part of the aqueous phase is discharged to a recovery column, a part of oil phase is performed reflux, and another part of the oil phase enters a rectification column as rough product to be further refined; and the rough product enters the rectification column from the middle of the same after being heated, a part of water and light components are removed by a membrane separator after a distillate at the top of the rectification column is condensed, a large part of the material reflows to the rectification column, a small part of the material is extracted to be reacted in the esterification reactor, and high-purity acetic acid mixed butyl ester is obtained at the bottom of the rectification column. Continuous production is achieved, and processes of neutralization, sedimentation and dehydration are omitted.

Description

A kind of successive reaction rectifying prepares the working method that acetic acid mixes butyl ester
Technical field
The present invention relates to a kind of successive reaction rectifying and prepare the working method that acetic acid mixes butyl ester, specifically is to be raw material to mix butanols and acetic acid, and successive reaction rectifying prepares acetic acid and mixes butyl ester under an acidic catalyst catalysis.
Background technology
It is a kind of colourless, inflammable, organic solvent commonly used of having the fruital flavor that acetic acid mixes butyl ester.Its main application is following: spices is made in (1); (2) make solvent; Acetic acid mixes butyl ester many materials is had good solubility; It can be used as the solvent of making Nitrocellulose, acrylic paint, polyurethane paint etc. in the industry; These lacquer classes can be used as aircraft wing coating, imitation leather coating, car paint etc., and acetic acid mixes the manufacturing that butyl ester also can be used for zylonite goods, art paper, coat of paint etc.; (3) useful as drug absorbs and promotes component; (4) make the reaction medium component; (5) make the metal cleaner component, remove the coating of metallic surface.
The raw materials for production that acetic acid mixes butyl ester are acetic acid and mixed butanols, wide material sources.Central mixed butanols is a kind of alcohol mixture, and have propyl carbinol, isopropylcarbinol, 2-butanols, propyl alcohol, amylalcohol and 3-methyl-2-butanols general the composition.Under the effect of acid catalyst, starting ester is combined to, and obtains mixing the butyl ester product with the acetic acid of fruital smell.Because the reaction raw materials complicated component, side reaction is more, and in order to ensure the quality that acetic acid mixes butyl ester, selection of catalysts is crucial.
At present, domestic production producer mostly adopts the rhythmic reaction production technique, generally comprises esterification, neutralization, sedimentation, dehydration, the multinomial operation of rectifying, uses the vitriol oil as catalysts usually.There is following subject matter in this conventional production methods:
1) producing is periodical operation, and device capbility is little; PT is long, and it is more that reaction generates by product, and yield is not high;
2) the catalyzer vitriol oil is serious to equipment corrosion, causes the ME cost higher;
3) the thick ester that reflects need neutralize with buck, produces great amount of wastewater, causes problems such as the higher and catalyst loss of acetic acid unit consumption simultaneously to a certain extent;
4) sediment such as catalyzer and acetate causes pipeline and filler to stop up easily, is unfavorable for producing.。
Generally speaking, there are problems such as tangible yield is on the low side, equipment corrosion is serious, wastewater flow rate is big, the material consumption energy consumption is higher in traditional esterification technique working method at intermittence, has restricted the popularization production of the mixed butyl ester of acetic acid greatly, has also influenced the market efficiency that acetic acid mixes butyl ester.
Summary of the invention
The present invention aims to provide a kind of successive reaction rectifying and prepares the working method that acetic acid mixes butyl ester, this method can avoid traditional batch production technique problems the problem includes: yield is low, seriously corroded, wastewater flow rate are big etc. problem, the production of realization clean environment firendly.
The present invention solves the defective that prior art exists and the technical scheme that adopts is: a kind of successive reaction rectifying prepares the working method that acetic acid mixes butyl ester; This working method may further comprise the steps: continue to heat up with getting into reaction kettle of the esterification after raw material acetic acid and the mixed butanols 1:1 mixing in molar ratio preheating; Reaction under an acidic catalyst catalysis, reaction product get into esterification column through heating with the azeotrope form and carry out initial gross separation, after the overhead product condensation phase-splitting of esterification column; Part aqueous-phase reflux is to esterification column; Another water drains into regenerating column, and a part of oil phase is back to esterification column, and it is further refining that another part oil phase gets into rectifying tower as thick product; Thick product gets into rectifying tower by the tower centre of rectifying tower after heating; The overhead product condensation of rectifying tower is after after membrane separation apparatus removes portion water and light constituent; Most of feed back is to rectifying tower; The esterifying kettle reaction is got back in few partial material extraction, obtains high purity acetic acid at the bottom of the tower of rectifying tower and mixes the butyl ester product.
Further, described mixed butanols is a kind of alcohol mixture, and this alcohol mixture contains 60% above propyl carbinol, 20% amylalcohol, 10% isopropylcarbinol, remains to be propyl alcohol, 2-butanols, 3-methyl-2-butanols.
Further, described catalysts is more than one in methylsulfonic acid, tosic acid and the sulfuric acid, and this catalysts accounts for the 0.5-5w% of total material.The catalysts of selecting for use among the present invention requires comprehensive selection property good, can effectively reduce the generation of side reaction.
Further, the still liquid still acid content in the described reaction kettle of the esterification is 20-50w%, and the reaction kettle of the esterification temperature is 100-130 ℃.
Further, the tower still temperature of described esterification column is that 110-130 ℃, tower medium temperature are that 100-120 ℃, tower top temperature are 85-95 ℃, and the oil phase material reflux ratio in the esterification column is 1-5, and the water reflux ratio is 1-3.
Use membrane sepn workshop section to remove the moisture more than 90% and few part light constituent in the rectifying tower top overhead product, to guarantee the trouble-free operation of successive reaction preparation in the inventive method.
The inventive method has realized that acetic acid mixes the continuous production of butyl ester, compares with batch production technology to have the following advantages:
1) saves neutralization, sedimentation, the dehydration procedure of batch technology, effectively reduced equipment investment cost;
2) catalysts has effectively been controlled the generation of side reaction, improves product yield; Simultaneously effectively improve the equipment corrosion problem, reduced equipment maintenance cost;
3) cancelled in and operation, saved neutralizing agent, reduce the loss of raw material acetic acid, reduce the waste water generation, realize cleaner production, reduce production costs;
4) technological operation is simple and convenient, and continuous production efficient is high, promotes the product economy benefit.
Description of drawings
Fig. 1 is that acetic acid of the present invention mixes butyl ester continuous production processes schematic flow sheet.
Wherein: 1-reboiler; 2-reaction kettle of the esterification; 3-esterification column; 4-esterification condensing surface; 5-esterification phase splitter; 6-rectifying tower; 7-rectifying condensing surface; 8-membrane sepn.
Embodiment
Embodiment 1
Raw material mixes butanols and acetic acid 1:1 entering in molar ratio reboiler 1, and inlet amount is 1500L/h, after the mixing preheating; Get into reaction kettle of the esterification 2; Under Catalyzed by p-Toluenesulfonic Acid agent catalysis, do further temperature reaction, the still temperature control is at 110-115 ℃, and reaction product gets into esterification column 3 with the azeotrope form.93 ℃, cat head are 90 ℃ in 113 ℃ of esterification Tata stills, the tower, and overhead product gets into phase splitter 5 after condensing surface 4 condensations cooling, and lower floor's water is back to esterification column by reflux ratio 1.1, and residue is sent to recovery system; The upper oil phase material is back to the esterification cat head by reflux ratio 2.5, and it is further refining that all the other send into rectifying tower 6 as the mixed butyl ester of thick acetic acid.At this moment, the content of the mixed butyl ester of thick acetic acid is about 85%.The rectifying tower top overhead product gets into membrane sepn 8 to remove 90% above moisture and part light constituent after condensing surface 7 coolings, major part is back to rectifying tower afterwards, and all the other deliver to the reaction kettle of the esterification reaction as an ester.Final 98.76% the mixed butyl ester of product acetic acid that at the bottom of the rectifying Tata, obtains.
Embodiment 2
Raw material mixes butanols and acetic acid 1:1 entering in molar ratio reboiler 1; Inlet amount is 1000L/h; After mixing preheating, get into reaction kettle of the esterification 2, under tosic acid and the catalysis of methylsulphonic acid mixed catalyst, do further temperature reaction; The still temperature control is at 105-115 ℃, and the reaction after product gets into esterification column 3 with the azeotrope form.95 ℃, cat head are 91 ℃ in 114 ℃ of esterification Tata stills, the tower, and overhead product gets into phase splitter 5 after condensing surface 4 condensations cooling, and lower floor's water is back to esterification column by reflux ratio 1.2, and residue is sent to recovery system; The upper oil phase material is back to the esterification cat head by reflux ratio 2.0, and it is further refining that all the other send into rectifying tower 6 as the mixed butyl ester of thick acetic acid.At this moment, the content of the mixed butyl ester of thick acetic acid is about 88%.The rectifying tower top overhead product gets into membrane sepn 8 to remove 90% above moisture and part light constituent after condensing surface 7 coolings, major part is back to rectifying tower afterwards, and all the other deliver to the reaction kettle of the esterification reaction as an ester.Final 99.0% the mixed butyl ester of product acetic acid that at the bottom of the rectifying Tata, obtains.

Claims (7)

1. a successive reaction rectifying prepares the working method that acetic acid mixes butyl ester; It is characterized in that: this working method may further comprise the steps: continue to heat up with getting into reaction kettle of the esterification after raw material acetic acid and the mixed butanols 1:1 mixing in molar ratio preheating; Reaction under an acidic catalyst catalysis, reaction product get into esterification column through heating with the azeotrope form and carry out initial gross separation, after the overhead product condensation phase-splitting of esterification column; Part aqueous-phase reflux is to esterification column; Another water drains into regenerating column, and a part of oil phase is back to esterification column, and it is further refining that another part oil phase gets into rectifying tower as thick product; Thick product gets into rectifying tower by the tower centre of rectifying tower after heating; The overhead product condensation of rectifying tower is after after membrane separation apparatus removes portion water and light constituent; Most of feed back is to rectifying tower; The esterifying kettle reaction is got back in few partial material extraction, obtains high purity acetic acid at the bottom of the tower of rectifying tower and mixes the butyl ester product.
2. prepare the working method that acetic acid mixes butyl ester according to the successive reaction rectifying described in the claim 1; It is characterized in that: described mixed butanols is a kind of alcohol mixture; This alcohol mixture contains 60% above propyl carbinol, 20% amylalcohol, 10% isopropylcarbinol, remains to be propyl alcohol, 2-butanols, 3-methyl-2-butanols.
3. prepare the working method that acetic acid mixes butyl ester according to the successive reaction rectifying described in the claim 1, it is characterized in that: described catalysts is more than one in methylsulfonic acid, tosic acid and the sulfuric acid, and this catalysts accounts for the 0.5-5w% of total material.
4. prepare the working method that acetic acid mixes butyl ester according to the successive reaction rectifying described in the claim 1, it is characterized in that: the still liquid still acid content in the described reaction kettle of the esterification is 20-50w%, and the reaction kettle of the esterification temperature is 100-130 ℃.
5. prepare the working method that acetic acid mixes butyl ester according to the successive reaction rectifying described in claim 1 or 4; It is characterized in that: the tower still temperature of described esterification column is that 110-130 ℃, tower medium temperature are that 100-120 ℃, tower top temperature are 85-95 ℃; Oil phase material reflux ratio in the esterification column is 1-5, and the water reflux ratio is 1-3.
6. any described successive reaction rectifying prepares the working method that acetic acid mixes butyl ester according to claim 1-4, it is characterized in that: described membrane separation apparatus can effectively separate the moisture more than 90% and few part light constituent in the overhead product.
7. any described successive reaction rectifying prepares the working method that acetic acid mixes butyl ester according to claim 1-4; It is characterized in that: the tower still temperature of said rectifying tower is that 120-140 ℃, tower medium temperature are 100-120 ℃; Tower top temperature is 85-95 ℃, and the tower still of rectifying tower can obtain the acetic acid of purity more than 98.5% and mix the butyl ester product.
CN2012101696745A 2012-05-29 2012-05-29 Method for preparing acetic acid mixed butyl ester by continuous reaction and rectification Pending CN102690197A (en)

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Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103058860A (en) * 2013-01-04 2013-04-24 宜兴市恒兴精细化工有限公司 System for producing ethyl butyrate continuously
CN103254067A (en) * 2013-04-28 2013-08-21 江门谦信化工发展有限公司 Esterification production method of isopropyl acetate
CN103739486A (en) * 2013-11-26 2014-04-23 泰兴金江化学工业有限公司 Production method for ethyl acetate crude product
CN104513157A (en) * 2014-11-28 2015-04-15 江门谦信化工发展有限公司 Propyl acetate efficient environmentally friendly production method
CN106008208A (en) * 2016-07-21 2016-10-12 江门谦信化工发展有限公司 Method for reducing light components in production process of acetic acid mixed butyl ester
CN106146303A (en) * 2016-07-26 2016-11-23 江门谦信化工发展有限公司 A kind of acetic acid mixes continuous process system and the method for butyl ester
CN107840808A (en) * 2017-10-30 2018-03-27 烟台国邦化工机械科技有限公司 Continuous reaction rectification production cyanoacetate compound, malonate compound device and its production technology
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
CN110066267A (en) * 2018-12-21 2019-07-30 江门谦信化工发展有限公司 One kind 2,2- dimethyl -4- methylol -1,3-dioxolane continuous production technology
CN111320549A (en) * 2018-12-13 2020-06-23 山东润博生物科技有限公司 Continuous production method and device for propanil
CN112409172A (en) * 2020-11-19 2021-02-26 江门谦信化工发展有限公司 Method and system for producing ethyl acetate
CN113620804A (en) * 2021-09-13 2021-11-09 盐城市春竹香料有限公司 Continuous esterification process and device for ethyl 2-methylbutyrate
CN114163320A (en) * 2021-12-17 2022-03-11 福建南平龙晟香精香料有限公司 Preparation method and device of ambrotone intermediate
CN114195815A (en) * 2021-12-31 2022-03-18 烟台国邦化工机械科技有限公司 Continuous esterification production process of trimethyl borate
CN116283554A (en) * 2023-05-18 2023-06-23 北京弗莱明科技有限公司 Industrial separation and purification method of trans-2-butenoic acid

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CN1326923A (en) * 2000-06-02 2001-12-19 唐山市冀东溶剂厂 Method for continuously producing butyl acetate
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Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103058860A (en) * 2013-01-04 2013-04-24 宜兴市恒兴精细化工有限公司 System for producing ethyl butyrate continuously
CN103254067A (en) * 2013-04-28 2013-08-21 江门谦信化工发展有限公司 Esterification production method of isopropyl acetate
CN103739486A (en) * 2013-11-26 2014-04-23 泰兴金江化学工业有限公司 Production method for ethyl acetate crude product
CN104513157A (en) * 2014-11-28 2015-04-15 江门谦信化工发展有限公司 Propyl acetate efficient environmentally friendly production method
CN104513157B (en) * 2014-11-28 2016-08-17 江门谦信化工发展有限公司 A kind of production method of propyl acetate high-efficiency environment friendly
CN106008208A (en) * 2016-07-21 2016-10-12 江门谦信化工发展有限公司 Method for reducing light components in production process of acetic acid mixed butyl ester
CN106008208B (en) * 2016-07-21 2019-02-19 江门谦信化工发展有限公司 A method of it reducing acetic acid and mixes light component in butyl ester production process
CN106146303A (en) * 2016-07-26 2016-11-23 江门谦信化工发展有限公司 A kind of acetic acid mixes continuous process system and the method for butyl ester
CN107840808A (en) * 2017-10-30 2018-03-27 烟台国邦化工机械科技有限公司 Continuous reaction rectification production cyanoacetate compound, malonate compound device and its production technology
CN111320549A (en) * 2018-12-13 2020-06-23 山东润博生物科技有限公司 Continuous production method and device for propanil
CN110066267A (en) * 2018-12-21 2019-07-30 江门谦信化工发展有限公司 One kind 2,2- dimethyl -4- methylol -1,3-dioxolane continuous production technology
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
CN110066267B (en) * 2018-12-21 2021-10-08 珠海谦信新材料有限公司 Continuous production process of 2, 2-dimethyl-4-hydroxymethyl-1, 3-dioxolane
CN112409172A (en) * 2020-11-19 2021-02-26 江门谦信化工发展有限公司 Method and system for producing ethyl acetate
CN112409172B (en) * 2020-11-19 2023-04-07 江门谦信化工发展有限公司 Method and system for producing ethyl acetate
CN113620804A (en) * 2021-09-13 2021-11-09 盐城市春竹香料有限公司 Continuous esterification process and device for ethyl 2-methylbutyrate
CN114163320A (en) * 2021-12-17 2022-03-11 福建南平龙晟香精香料有限公司 Preparation method and device of ambrotone intermediate
CN114163320B (en) * 2021-12-17 2023-12-12 福建南平龙晟香精香料有限公司 Preparation method and device of ambroxol intermediate
CN114195815A (en) * 2021-12-31 2022-03-18 烟台国邦化工机械科技有限公司 Continuous esterification production process of trimethyl borate
CN116283554A (en) * 2023-05-18 2023-06-23 北京弗莱明科技有限公司 Industrial separation and purification method of trans-2-butenoic acid
CN116283554B (en) * 2023-05-18 2023-07-25 北京弗莱明科技有限公司 Industrial separation and purification method of trans-2-butenoic acid

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Application publication date: 20120926