CN108569972A - A kind of preparation method of t-butylaminoethyl methacrylate - Google Patents
A kind of preparation method of t-butylaminoethyl methacrylate Download PDFInfo
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- CN108569972A CN108569972A CN201810571045.2A CN201810571045A CN108569972A CN 108569972 A CN108569972 A CN 108569972A CN 201810571045 A CN201810571045 A CN 201810571045A CN 108569972 A CN108569972 A CN 108569972A
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C213/00—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton
- C07C213/06—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton from hydroxy amines by reactions involving the etherification or esterification of hydroxy groups
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C213/00—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton
- C07C213/10—Separation; Purification; Stabilisation; Use of additives
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- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a kind of preparation methods of t-butylaminoethyl methacrylate, include the following steps：S1：Transesterification；S2：Centrifugal sedimentation；S3：TBAEMA rectifying；S4：Methanol Recovery.The present invention uses solid base catalyst, and after the completion of reaction, using the method for centrifugal sedimentation, catalyst is separately come out, and reuses, improves the yield of product, reduce the usage amount of catalyst, improve economic benefit, save resource, reduce discharge.
Description
Technical field
The present invention relates to chemical production technical field, specially a kind of preparation side of t-butylaminoethyl methacrylate
Method.
Background technology
T-butylaminoethyl methacrylate (TBAEMA) also known as methacrylic acid -2- t-butylaminoethyls, are used as
Polymer modification agent.By methacrylic acid cresols and t-butylaminoethyl carry out ester exchange reaction be made, also can be by first
Base acrylic acid directly carries out esterification and is made with t-butylaminoethyl, prepares the crosslinking agent of thermohardening lacquer, conspicuous mixture etc.
And lube oil additive and pigment colorant etc..
Methacrylic acid tertiary butyl is prepared using methyl methacrylate and tertiary butyl ethanol amine (R-OH) ester exchange reaction
The liquid catalysts such as amino ethyl ester generally use organotin, titanate esters gradually produce methanol and methyl in reaction process from tower top
The azeotropic mixture of methyl acrylate after the completion of reaction, carries out rectifying and recycles methyl methacrylate, and obtain product.Azeotropic mixture exists
Methyl methacrylate is recycled by azeotropic distillation, and obtains methanol.Reaction solution containing catalyst carries out rectifying, catalyst meeting
It stays in the heavy constituent of bottom of tower, heavy constituent causes the loss of product and catalyst, azeotropic mixture processing so usually by burning disposal
Process complexity and high energy consumption.How to improve product yield and reduce catalyst loss as those skilled in the art it is urgently to be resolved hurrily
Major issue.
Invention content
It is above-mentioned to solve the purpose of the present invention is to provide a kind of preparation method of t-butylaminoethyl methacrylate
The problem of being proposed in background technology.
To achieve the above object, the present invention provides the following technical solutions：A kind of t-butylaminoethyl methacrylate
Preparation method includes the following steps：
S1：Transesterification, is added methyl methacrylate into ten cubes of reaction kettles, tertiary butyl ethanol amine, polymerization inhibitor and solid
Body base catalyst, opens agitating device and heating device, and after 30~50min of infinite reflux, control tower top temperature is stablized 50~60
DEG C, partial reflux liquid produces the azeotropic mixture of methyl methacrylate and methanol, until ester exchange reaction is completed, bottom of tower extraction is containing solid
The TBAEMA mixed liquors of body base catalyst；
S2：TBAEMA mixed liquors in step 1 are transferred to tubular-bowl centrifuge, carry out centrifugal sedimentation by centrifugal sedimentation,
The rotating speed for controlling centrifuge is 10000~15000r/min, after persistently centrifuging 10~30min, after collecting bottom solid phase and drying
Solid base catalyst is obtained, the top liquid phase of sedimentation centrifuge is collected, obtains thick TBAEMA liquid；
S3：Thick TBAEMA liquid in step 2 is transferred in rectifying column by TBAEMA rectifying, and methyl is produced from rectifying tower top
Tbutylaminoethylacrylate obtains mixture impurity from rectifying column bottom and carries out innoxious burning processing；
S4：Methanol Recovery, by the azeotropic mixture of methyl methacrylate and methanol in step 2 be initially cooled to 60 DEG C hereinafter,
It is then transferred in extraction tower, desalted water is selected to obtain methanol solution and first in such a way that multistage inversely extracts as extractant
Base methyl acrylate, methanol solution carry out distillation operation by the way of methanol three-tower rectification, obtain light group of normal pressure column overhead
It is divided into methanol, the heavy constituent that atmospheric tower bottom of tower obtains is recycled.
Preferably, in step 1, the solid catalyst be alkali or alkaline earth metal oxide or hydroxide such as
Calcium oxide, lithium hydroxide etc., rare earth oxide lanthana, cerium oxide etc., the 4th main group oxide such as stannous oxide, lead oxide and
One or several kinds of mixtures of sulfate, disulfate, phosphate, hydrophosphate, the rhodanate of first, second main group etc..
Preferably, in step 1, the polymerization inhibitor includes hydroquinone, p-hydroxyanisole, 2,6 di-tert-butylphenol equipotentials
It is one such or a variety of to hinder phenols, azo piperidines free radical and its ester, phenthazine etc..
Preferably, in step 1, the mixing speed of the agitating device is controlled in 700~1000r/min.
Preferably, in step 1, the mark that ester exchange reaction is completed is that alcohol content in tower reactor is less than 50ppm.
Compared with prior art, the beneficial effects of the invention are as follows：
1. the present invention uses solid base catalyst, after the completion of reaction, using the method for centrifugal sedimentation, catalyst point is opened out
Coming, recycling improves the yield of product, reduces the usage amount of catalyst, improve economic benefit, save resource,
Reduce discharge；
2. the required equipment of the present invention is less, easy to operate, catalyst, which is applied mechanically, reduces discharge, improves product yield,
By carrying out innoxious burning processing to waste liquid, environmental protection is realized.
Specific implementation mode
Below in conjunction in the embodiment of the present invention, technical solution in the embodiment of the present invention is clearly and completely retouched
It states, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.Based on the present invention
In embodiment, every other implementation obtained by those of ordinary skill in the art without making creative efforts
Example, shall fall within the protection scope of the present invention.
Embodiment 1
The present invention provides a kind of technical solution：A kind of preparation method of t-butylaminoethyl methacrylate, including with
Lower step：
S1：Transesterification, is added methyl methacrylate into ten cubes of reaction kettles, tertiary butyl ethanol amine, polymerization inhibitor and solid
Body base catalyst, opens agitating device and heating device, and after infinite reflux 30min, control tower top temperature is stablized at 50 DEG C, and part is returned
Flow liquid produces the azeotropic mixture of methyl methacrylate and methanol, until ester exchange reaction is completed, bottom of tower extraction contains catalyzed by solid base
The TBAEMA mixed liquors of agent；
S2：TBAEMA mixed liquors in step 1 are transferred to tubular-bowl centrifuge, carry out centrifugal sedimentation by centrifugal sedimentation,
The rotating speed for controlling centrifuge is 12000r/min, after persistently centrifuging 10min, collects bottom solid phase and obtains solid base after drying and urge
Agent collects the top liquid phase of sedimentation centrifuge, obtains thick TBAEMA liquid；
S3：Thick TBAEMA liquid in step 2 is transferred in rectifying column by TBAEMA rectifying, and methyl is produced from rectifying tower top
Tbutylaminoethylacrylate obtains mixture impurity from rectifying column bottom and carries out innoxious burning processing；
S4：Methanol Recovery, by the azeotropic mixture of methyl methacrylate and methanol in step 2 be initially cooled to 60 DEG C hereinafter,
It is then transferred in extraction tower, desalted water is selected to obtain methanol solution and first in such a way that multistage inversely extracts as extractant
Base methyl acrylate, methanol solution carry out distillation operation by the way of methanol three-tower rectification, obtain light group of normal pressure column overhead
It is divided into methanol, the heavy constituent that atmospheric tower bottom of tower obtains is recycled.
Wherein, in step 1, solid catalyst be alkali or alkaline earth metal oxide or hydroxide such as calcium oxide,
Lithium hydroxide etc., rare earth oxide lanthana, cerium oxide etc., the 4th main group oxide such as stannous oxide, lead oxide and first,
One or several kinds of mixtures of sulfate, disulfate, phosphate, hydrophosphate, the rhodanate of two main groups etc.；Step 1
In, polymerization inhibitor includes hydroquinone, p-hydroxyanisole, 2, the hindered phenolics such as 6 di-tert-butylphenols, azo piperidines free radical and its
Ester, phenthazine etc. are one such or a variety of；In step 1, the mixing speed of agitating device is controlled in 700~1000r/min；
In step 1, the mark that ester exchange reaction is completed is that alcohol content in tower reactor is less than 50ppm.
Embodiment 2
The present invention provides a kind of technical solution：A kind of preparation method of t-butylaminoethyl methacrylate, including with
Lower step：
S1：Transesterification, is added methyl methacrylate into ten cubes of reaction kettles, tertiary butyl ethanol amine, polymerization inhibitor and solid
Body base catalyst, opens agitating device and heating device, and after infinite reflux 40min, control tower top temperature is stablized at 55 DEG C, and part is returned
Flow liquid produces the azeotropic mixture of methyl methacrylate and methanol, until ester exchange reaction is completed, bottom of tower extraction contains catalyzed by solid base
The TBAEMA mixed liquors of agent；
S2：TBAEMA mixed liquors in step 1 are transferred to tubular-bowl centrifuge, carry out centrifugal sedimentation by centrifugal sedimentation,
The rotating speed for controlling centrifuge is 15000r/min, after persistently centrifuging 20min, collects bottom solid phase and obtains solid base after drying and urge
Agent collects the top liquid phase of sedimentation centrifuge, obtains thick TBAEMA liquid；
S3：Thick TBAEMA liquid in step 2 is transferred in rectifying column by TBAEMA rectifying, and methyl is produced from rectifying tower top
Tbutylaminoethylacrylate obtains mixture impurity from rectifying column bottom and carries out innoxious burning processing；
S4：Methanol Recovery, by the azeotropic mixture of methyl methacrylate and methanol in step 2 be initially cooled to 60 DEG C hereinafter,
It is then transferred in extraction tower, desalted water is selected to obtain methanol solution and first in such a way that multistage inversely extracts as extractant
Base methyl acrylate, methanol solution carry out distillation operation by the way of methanol three-tower rectification, obtain light group of normal pressure column overhead
It is divided into methanol, the heavy constituent that atmospheric tower bottom of tower obtains is recycled.
Wherein, in step 1, solid catalyst be alkali or alkaline earth metal oxide or hydroxide such as calcium oxide,
Lithium hydroxide etc., rare earth oxide lanthana, cerium oxide etc., the 4th main group oxide such as stannous oxide, lead oxide and first,
One or several kinds of mixtures of sulfate, disulfate, phosphate, hydrophosphate, the rhodanate of two main groups etc.；Step 1
In, polymerization inhibitor includes hydroquinone, p-hydroxyanisole, 2, the hindered phenolics such as 6 di-tert-butylphenols, azo piperidines free radical and its
Ester, phenthazine etc. are one such or a variety of；In step 1, the mixing speed of agitating device is controlled in 700~1000r/min；
In step 1, the mark that ester exchange reaction is completed is that alcohol content in tower reactor is less than 50ppm.
Embodiment 3
The present invention provides a kind of technical solution：A kind of preparation method of t-butylaminoethyl methacrylate, including with
Lower step：
S1：Transesterification, is added methyl methacrylate into ten cubes of reaction kettles, tertiary butyl ethanol amine, polymerization inhibitor and solid
Body base catalyst, opens agitating device and heating device, and after infinite reflux 50min, control tower top temperature is stablized at 60 DEG C, and part is returned
Flow liquid produces the azeotropic mixture of methyl methacrylate and methanol, until ester exchange reaction is completed, bottom of tower extraction contains catalyzed by solid base
The TBAEMA mixed liquors of agent；
S2：TBAEMA mixed liquors in step 1 are transferred to tubular-bowl centrifuge, carry out centrifugal sedimentation by centrifugal sedimentation,
The rotating speed for controlling centrifuge is 15000r/min, after persistently centrifuging 30min, collects bottom solid phase and obtains solid base after drying and urge
Agent collects the top liquid phase of sedimentation centrifuge, obtains thick TBAEMA liquid；
S3：Thick TBAEMA liquid in step 2 is transferred in rectifying column by TBAEMA rectifying, and methyl is produced from rectifying tower top
Tbutylaminoethylacrylate obtains mixture impurity from rectifying column bottom and carries out innoxious burning processing；
S4：Methanol Recovery, by the azeotropic mixture of methyl methacrylate and methanol in step 2 be initially cooled to 60 DEG C hereinafter,
It is then transferred in extraction tower, desalted water is selected to obtain methanol solution and first in such a way that multistage inversely extracts as extractant
Base methyl acrylate, methanol solution carry out distillation operation by the way of methanol three-tower rectification, obtain light group of normal pressure column overhead
It is divided into methanol, the heavy constituent that atmospheric tower bottom of tower obtains is recycled.
Wherein, in step 1, solid catalyst be alkali or alkaline earth metal oxide or hydroxide such as calcium oxide,
Lithium hydroxide etc., rare earth oxide lanthana, cerium oxide etc., the 4th main group oxide such as stannous oxide, lead oxide and first,
One or several kinds of mixtures of sulfate, disulfate, phosphate, hydrophosphate, the rhodanate of two main groups etc.；Step 1
In, polymerization inhibitor includes hydroquinone, p-hydroxyanisole, 2, the hindered phenolics such as 6 di-tert-butylphenols, azo piperidines free radical and its
Ester, phenthazine etc. are one such or a variety of；In step 1, the mixing speed of agitating device is controlled in 700~1000r/min；
In step 1, the mark that ester exchange reaction is completed is that alcohol content in tower reactor is less than 50ppm.
Three above embodiment can prepare the t-butyl aminoethyl that content is 99.5%, yield is 99%
Ethyl ester, and after by-product is dehydrated by extracting rectifying, the methanol that content is 99.5%, wherein solid in embodiment three can be obtained
For base catalyst after centrifugal sedimentation, catalytic activity is most strong, and catalyst applies mechanically lower secondary response, obtained methacrylic acid uncle
Butylaminoethyl is consistent with methanol result, illustrates that tubular-bowl centrifuge rotating speed is faster, the sedimentation time is longer, catalyzed by solid base
The activity of agent is better.
It although an embodiment of the present invention has been shown and described, for the ordinary skill in the art, can be with
Understanding without departing from the principles and spirit of the present invention can carry out these embodiments a variety of variations, modification, replace
And modification, the scope of the present invention is defined by the appended.
Claims (5)
1. a kind of preparation method of t-butylaminoethyl methacrylate, it is characterised in that：Include the following steps：
S1：Methyl methacrylate, tertiary butyl ethanol amine, polymerization inhibitor and solid base are added into ten cubes of reaction kettles for transesterification
Catalyst, opens agitating device and heating device, and after 30~50min of infinite reflux, control tower top temperature is stablized at 50~60 DEG C, portion
Divide the azeotropic mixture of phegma extraction methyl methacrylate and methanol, until ester exchange reaction is completed, bottom of tower extraction is containing solid base
The TBAEMA mixed liquors of catalyst；
S2：TBAEMA mixed liquors in step 1 are transferred to tubular-bowl centrifuge by centrifugal sedimentation, carry out centrifugal sedimentation, control
The rotating speed of centrifuge is 10000~15000r/min, after persistently centrifuging 10~30min, collects bottom solid phase and is obtained after drying
Solid base catalyst collects the top liquid phase of sedimentation centrifuge, obtains thick TBAEMA liquid；
S3：Thick TBAEMA liquid in step 2 is transferred in rectifying column by TBAEMA rectifying, and metering system is produced from rectifying tower top
Sour t-butylaminoethyl obtains mixture impurity from rectifying column bottom and carries out innoxious burning processing；
S4：The azeotropic mixture of methyl methacrylate and methanol in step 2 is initially cooled to 60 DEG C, is then transferred to by Methanol Recovery
In extraction tower, desalted water is selected to obtain methanol solution and methacrylic acid in such a way that multistage inversely extracts as extractant
Methyl esters, methanol solution carry out distillation operation by the way of methanol three-tower rectification, and the light component that normal pressure column overhead obtains is methanol,
The heavy constituent that atmospheric tower bottom of tower obtains is recycled.
2. a kind of preparation method of t-butylaminoethyl methacrylate according to claim 1, it is characterised in that：Step
In rapid one, the solid catalyst is the oxide or hydroxide such as calcium oxide, lithium hydroxide etc. of alkali or alkaline earth metal,
Rare earth oxide lanthana, cerium oxide etc., the sulphur of the 4th main group oxide such as stannous oxide, lead oxide and the first, second main group
One or several kinds of mixtures of hydrochlorate, disulfate, phosphate, hydrophosphate, rhodanate etc..
3. a kind of preparation method of t-butylaminoethyl methacrylate according to claim 1, it is characterised in that：Step
In rapid one, the polymerization inhibitor includes hydroquinone, p-hydroxyanisole, 2, and the hindered phenolics such as 6 di-tert-butylphenols, azo piperidines are certainly
It is one such or a variety of by base and its ester, phenthazine etc..
4. a kind of preparation method of t-butylaminoethyl methacrylate according to claim 1, it is characterised in that：Step
In rapid one, the mixing speed of the agitating device is controlled in 700~1000r/min.
5. a kind of preparation method of t-butylaminoethyl methacrylate according to claim 1, it is characterised in that：Step
In rapid one, the mark that ester exchange reaction is completed is that alcohol content in tower reactor is less than 50ppm.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62175448A (en) * | 1986-01-28 | 1987-08-01 | Mitsui Toatsu Chem Inc | Production of alkylaminoalkyl acrylate or methacrylate |
| JPS62242652A (en) * | 1986-04-16 | 1987-10-23 | Mitsui Toatsu Chem Inc | Production of acrylic acid or methacrylic acid alkylaminoalkyl ester |
| CN102584605A (en) * | 2011-12-31 | 2012-07-18 | 武汉大学 | Synthetic method of imino-containing unsaturated monomer |
| WO2017032699A1 (en) * | 2015-08-21 | 2017-03-02 | Basf Se | Method for producing low-boiling (meth)acrylic acid esters |
| CN106588654A (en) * | 2016-03-25 | 2017-04-26 | 中国石油集团东北炼化工程有限公司吉林设计院 | Extraction method and system for methyl methacrylate preparation process |
-
2018
- 2018-06-05 CN CN201810571045.2A patent/CN108569972A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62175448A (en) * | 1986-01-28 | 1987-08-01 | Mitsui Toatsu Chem Inc | Production of alkylaminoalkyl acrylate or methacrylate |
| JPS62242652A (en) * | 1986-04-16 | 1987-10-23 | Mitsui Toatsu Chem Inc | Production of acrylic acid or methacrylic acid alkylaminoalkyl ester |
| CN102584605A (en) * | 2011-12-31 | 2012-07-18 | 武汉大学 | Synthetic method of imino-containing unsaturated monomer |
| WO2017032699A1 (en) * | 2015-08-21 | 2017-03-02 | Basf Se | Method for producing low-boiling (meth)acrylic acid esters |
| CN106588654A (en) * | 2016-03-25 | 2017-04-26 | 中国石油集团东北炼化工程有限公司吉林设计院 | Extraction method and system for methyl methacrylate preparation process |
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Application publication date: 20180925 |