CN106478402A - The method that ethanol acid crystal is prepared by methyl glycollate - Google Patents
The method that ethanol acid crystal is prepared by methyl glycollate Download PDFInfo
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- CN106478402A CN106478402A CN201510541668.1A CN201510541668A CN106478402A CN 106478402 A CN106478402 A CN 106478402A CN 201510541668 A CN201510541668 A CN 201510541668A CN 106478402 A CN106478402 A CN 106478402A
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- Prior art keywords
- methyl glycollate
- acid crystal
- ethanol acid
- reactive distillation
- distillation column
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/09—Preparation of carboxylic acids or their salts, halides or anhydrides from carboxylic acid esters or lactones
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/42—Separation; Purification; Stabilisation; Use of additives
- C07C51/43—Separation; Purification; Stabilisation; Use of additives by change of the physical state, e.g. crystallisation
Abstract
The present invention relates to a kind of method that ethanol acid crystal is prepared by methyl glycollate, mainly solve that reaction present in prior art is discontinuous, complex process, be difficult commercial Application, high energy consumption, circulating load excessive the problems such as.The present invention, using a kind of new method being prepared glycolic-aqueous mixtures by methyl glycollate, comprises the steps of：A) by methyl glycollate and water in mass ratio 1:(0.5～10) deliver to reactive distillation column after mixing, under conditions of the weight space velocity that tower presses 5kPa～100kPa, methyl glycollate is no more than 5, tower reactor obtains aqueous 10%～50% glycolic-aqueous mixtures.B) above-mentioned glycolic-aqueous mixtures are sent into crystallisation by cooling module, crystallisation by cooling in -15～5 DEG C of temperature range, separate out ethanol acid crystal, remaining mother solution returns reactive distillation column simultaneously.This method preferably solves this problem, can be used for the commercial production that methyl glycollate prepares ethanol acid crystal.
Description
Technical field
The present invention relates to the method that glycolic-aqueous mixtures are prepared by methyl glycollate.
Background technology
Methyl glycollate, due to its unique molecular structure, has the chemical property of alcohol and ester, Neng Goufa concurrently
Raw oxonation, hydrolysis, oxidation reaction etc., become a kind of important industrial chemicals.Can be extensive
For the many such as chemical industry, medicine, pesticide, feedstuff, spice and fuel fields.
Glycolic, also known as hydroxyacetic acid, glycolic acid, is also a kind of important organic synthesis intermediate and change
Chemical product, is widely used in the industries such as organic synthesiss, cleaning, plating, weaving, leather, sterilizing.
In recent years, scientific research finds that the polymer of hydroxyacetic acid has biodegradability, solves tradition
The problem being difficult to degrade that plastic exists, can be widely used in medical science, packaging and other many
Field.
Methyl glycollate and glycolic because of its of many uses and good market prospect, both at home and abroad to this two
The synthesising process research planting product is very many, and mainly having that research is more at present is following several：
1. chloroactic acid method.The method is to mix monoxone with soda lye, stir evenly.In boiling water bath
Upper heating, is evaporated under reduced pressure, filters sodium chloride, heat to obtain paste liquid, afterwards in oil bath
Add methanol and concentrated sulphuric acid, flow back to obtain methyl glycollate, with sodium carbonate neutralization, stand overnight,
Vacuum fractionation obtains product methyl glycollate.
2. formaldehyde and hydrocyanic acid addition process.This method is obtained with formaldehyde and hydrocyanic acid for raw material under sulfuric acid catalysis
To hydroxyl second eyeball, then hydrolyze, esterification can get the methyl glycollate that gross production rate is 80%.
3. oxalate hydrogenating reduction method.This method is more in Italy's research eighties in 20th century, adopts
Ruthenium is catalyst, 180 DEG C of reaction temperature, Hydrogen Vapor Pressure 13.2MPa, and yield reaches 100%.
Improve catalyst structure afterwards again, make reaction condition become more gentle, yield also has 95%.
But this kind of catalyst is organic precious metal catalyst, complicated process of preparation, expensive
It is difficult to reclaim.Japan have developed carried copper silver catalyst, and oxalic acid ester conversion rate is about
90.2%, methyl glycollate yield is 68%, space-time yield 202.7g/ (L.h).
Apart from the above, also：Biformyl and methanol one-step synthesis, formaldehyde carbonylation -ester synthetic method,
Ester dimethoxym ethane and formic acid method, coupling method, dimethoxym ethane and Formaldehyde Radical addition process, enzyme oxidizing process
Glycolic can be prepared etc. method.
CN103508878 is related to a kind of method preparing high purity ethanol acid crystal by methyl glycollate,
The method comprises the following steps：(1) methyl glycollate and water is 1 in mass ratio: (1～20) mixes,
At 20～100 DEG C, under 80KPa～normal pressure, hydrolysis 0.5～4hr, obtain the water containing glycolic
Solution liquid；(2) hydrolyzed solution containing glycolic obtaining step (1) is at 30～90 DEG C, and pressure is 5～
80kPa carries out concentration process, obtains the ethanol acid mother liquor of high concentration；(3) to containing high concentration ethanol acid
Mother solution, at -10～15 DEG C, under normal pressure, carries out crystallisation by cooling, obtains purity and is more than the high-purity of 99.5wt%
Degree ethanol acid crystal.But there is the problems such as long flow path, high energy consumption in this method.
CN104177250A is related to a kind of side being prepared high purity ethanol acid crystal by methyl glycollate
Method, the method comprises reactive distillation, evaporation and concentration, decolouring, crystallization, drying and other steps can get second
Alcohol acid crystal.But wherein reactive distillation needs infinite reflux step therefore cannot realize the stable and continuous behaviour of tower
Make, and in tower reactor the time of staying long excessive impurity is produced to meeting, the program needs volume simultaneously
Outer evaporation-concentration step, increased the complexity of flow process.
Although the technique that can synthesize is more, a lot of techniques all have the shortcomings that larger, at present abroad
Main production line is the carbonylation route using formaldehyde for raw material, but equipment corrosion-resistant and high pressure resistant will
Ask higher, the disposable input of equipment larger it is impossible to large-scale production.Domestic methyl glycollate and second
The production of alkyd has always been continued to use the technique road of monoxone and soda lye hybrid reaction resterification
Line, it is raw material that chloroacetic production adopts acetic acid, and sulfur is catalyst, and chlorine method produces although process
Simply, seriously corroded but in production process, pollution are big, high cost is thus lead to this method can not advise greatly
Mould produces.And due to prepare glycolic polymer when, the purity requirement to glycolic acid monomers is higher,
This kind of production method cannot meet this requirement.And with oxalate for raw material preparation of ethanol by hydrogenating acid methyl ester and
The method of glycolic have environmental protection, can heavy industrialization and obtain high purity ethanol acid methyl ester and
The advantage of glycolic, so exploitation the method is significant.
When method in document above prepares glycolic for methyl glycollate, it is long all to there is technological process,
Pollution is big, be not easy to the problem of heavy industrialization application.
Content of the invention
The technical problem to be solved is that to react discontinuous, technique present in prior art multiple
Miscellaneous, be difficult commercial Application, high energy consumption, for the not strong problem of the adaptability of raw material, there is provided a kind of
The new method that glycolic-aqueous mixtures are prepared by methyl glycollate.The method is used for methyl glycollate system
During standby glycolic, have and react continuous, process is simple it is easy to commercial Application, energy consumption are low, for former
The adaptable advantage of material.
For solving above-mentioned technical problem, the technical scheme that the present invention takes is as follows：One kind is by glycolic first
Ester prepares the method for glycolic-aqueous mixtures it is characterised in that comprising the steps of：
A) by methyl glycollate and water in mass ratio 1:(0.5～10) deliver to reactive distillation column after mixing,
Under conditions of tower presses the weight space velocity of 5kPa～85kPa, methyl glycollate to be no more than 5, tower reactor obtains
Aqueous 10%～50% glycolic-aqueous mixtures.
B) above-mentioned glycolic-aqueous mixtures are sent into crystallisation by cooling module, in -15～5 DEG C of temperature range
Interior crystallisation by cooling, separates out ethanol acid crystal, and remaining mother solution returns reactive distillation column simultaneously.
It is preferable that using solid acid as urging in described reactive distillation column in technique scheme
Agent；
It is highly preferred that solid acid catalyst be resin, at least one in molecular sieve.
It is preferable that catalyst is at least seated in stripping section in technique scheme.
In technique scheme it is preferable that in described reactive distillation column temperature be 5～90 DEG C.
It is preferable that described reaction velocity is 0.5～3 in technique scheme.
It is preferable that methyl glycollate and water in mass ratio 1 in technique scheme:(0.5～5)；More excellent
Selection of land, methyl glycollate and water in mass ratio 1:(0.8～3)；
It is preferable that tower is pressed as 5kPa～80kPa in technique scheme；It is highly preferred that tower is pressed being
10kPa～50kPa；
It is preferable that tower reactor obtains aqueous 10%～35% glycolic-water mixing in technique scheme
Thing；It is highly preferred that tower reactor obtains aqueous 10%～30% glycolic-aqueous mixtures.
It is preferable that methyl glycollate and water in mass ratio 1 in technique scheme:(0.5～5), tower pressure
For, under 5kPa～80kPa, tower reactor obtains aqueous 10%～35% glycolic-aqueous mixtures；
In technique scheme, it is highly preferred that methyl glycollate and water in mass ratio 1:(0.8～3), tower
Press as, under 10kPa～50kPa, tower reactor obtains aqueous 10%～30% glycolic-aqueous mixtures.
In technique scheme it is preferable that in reactive distillation column temperature be 30～100 DEG C.
In technique scheme, it is highly preferred that temperature is 40～90 DEG C in reactive distillation column.
It is preferable that reaction velocity is 0.2～5 in technique scheme.
In technique scheme, it is highly preferred that reaction velocity is 0.5～3.
It is preferable that to it before glycolic-aqueous mixtures is sent into evaporative crystallization in technique scheme
Carry out desolventing technology.
It is preferable that the temperature range of crystallization is -10～5 DEG C in technique scheme.
In technique scheme, it is highly preferred that the temperature range of crystallization is -10～-3 DEG C.
In technique scheme, most preferably, the temperature range of crystallization is -10～-5 DEG C.
Percentage composition in technique scheme is all weight percentage, and air speed is weight space velocity.
It is balancing response that ethanol acid reaction is prepared in methyl glycollate hydrolysis, balancing response group under uniform temperature
Become to fix, therefore be difficult to obtain high conversion using conventional meanses.All can using non-reactive distillation mode
With the presence of unreacted methyl glycollate, in order to convert it completely, need to arrange multitower separation process,
And it is faced with the too high problem of bottom temperature.This method adopts under reactive distillation column form single column flow process
Methyl glycollate substantially completely can be converted, can get ethanol acid product in reactive distillation column, can basis
Downstream demand adjusts the concentration of glycolic.The inventive method is succinct, reaction condition is gentle, production process
In without non-toxic substance, environmentally friendly, the product that obtains is easy to transport, compared to existing technology
CN103508878, its products scheme is more flexible, and flow process is more succinct, reduced investment, and energy consumption is low.Phase
Have than CN104177250:Whole process continuous and stable operates without recovery catalyst；Stable state produces
During without infinite reflux；The advantages of air speed height is easy to engineering construction.
Brief description
Fig. 1 is the process flow diagram of the present invention.
In Fig. 1,1 is the logistics containing methyl glycollate and water, and 2 contain methanol for reactive distillation column overhead
With the logistics of water, 3 is reactive distillation column tower reactor methyl glycollate aqueous solution logistics, and 4 is following after crystallizing
Ring mother solution, 5 is the ethanol acid crystal separating out, and I is reactive distillation column, and II is crystallisation by cooling module.
Reactive distillation column tower is delivered in logistics 1 containing methyl glycollate and water and carries out reactive distillation, tower top
Obtain the logistics 2 containing methanol and water, reactive distillation column tower reactor obtains methyl glycollate aqueous solution logistics 3,
Ethanol acid crystal 5 is obtained, remaining mother liquor stream 4 returns reactive distillation column after logistics 3 is crystallized.
Below by embodiment, the invention will be further elaborated, but these embodiments are anyway
The scope of the present invention is not construed as limiting.
Specific embodiment
【Embodiment 1】
By methyl glycollate and water in mass ratio 1:Deliver to reactive distillation column after 10 mixing, press 5kPa in tower
Under, the Temperature Distribution of reactive distillation column overhead to tower reactor is 12～54 DEG C, and catalyst is resin catalyst,
Air speed is 1.5h-1, tower reactor obtains aqueous 10% glycolic-aqueous mixtures, is sent to crystallisation by cooling
Module, separates out ethanol acid crystal at a temperature of -10 DEG C, and remaining Recycling Mother Solution returns reactive distillation column,
Methyl glycollate conversion ratio 99.5%, selectivity 98%, the ethanol acid crystal response rate 95%.
【Embodiment 2】
By methyl glycollate and water in mass ratio 1:Deliver to reactive distillation column after 0.5 mixing, press 5kPa in tower
Under, the Temperature Distribution of reactive distillation column overhead to tower reactor is -13～54 DEG C, and catalyst is resin catalyst,
Air speed is 0.3h-1, tower reactor obtains aqueous 10% glycolic-aqueous mixtures, is sent to crystallisation by cooling
Module, separates out ethanol acid crystal at a temperature of 5 DEG C, and remaining Recycling Mother Solution returns reactive distillation column,
The conversion ratio of methyl glycollate is 99.8%, selectivity 95%, the selectivity ethanol acid crystal response rate
93%.
【Embodiment 3】
By methyl glycollate and water in mass ratio 1:Reactive distillation column is delivered to, in tower pressure after 10 mixing
Under 85kPa, the Temperature Distribution of reactive distillation column overhead to tower reactor is 82～99 DEG C, and catalyst is urged for resin
Agent, air speed is 10h-1, tower reactor obtains aqueous 50% glycolic-aqueous mixtures, is sent to cold
But crystallize module, separate out ethanol acid crystal at a temperature of -10 DEG C, remaining Recycling Mother Solution returns reaction essence
Evaporate tower, the conversion ratio of methyl glycollate is 95%, selectivity 85%, the ethanol acid crystal response rate 91%.
【Embodiment 4】
By methyl glycollate and water in mass ratio 1:Reactive distillation column is delivered to, in tower pressure after 0.5 mixing
Under 10kPa, the Temperature Distribution of reactive distillation column overhead to tower reactor is 6～66 DEG C, and catalyst is molecular sieve
Catalyst, air speed is 0.6h-1, tower reactor obtains aqueous 10% glycolic-aqueous mixtures, is sent to
Crystallisation by cooling module, separates out ethanol acid crystal at a temperature of -5 DEG C, and remaining Recycling Mother Solution returns reaction
Rectifying column, the conversion ratio of methyl glycollate is 98%, selectivity 97%, the ethanol acid crystal response rate 95%.
【Embodiment 5】
By methyl glycollate and water in mass ratio 1:Deliver to reactive distillation column after 3 mixing, press 50kPa in tower
Under, the Temperature Distribution of reactive distillation column overhead to tower reactor is 68～90 DEG C, and catalyst is resin catalyst,
Air speed is 2h-1, tower reactor obtains aqueous 35% glycolic-aqueous mixtures, is sent to crystallisation by cooling mould
Block, separates out ethanol acid crystal at a temperature of -10 DEG C, and remaining Recycling Mother Solution returns reactive distillation column, second
The conversion ratio of alkyd methyl ester is 99.5%, selectivity 95%, the ethanol acid crystal response rate 96%.
【Embodiment 6】
By methyl glycollate and water in mass ratio 1:Reactive distillation column is delivered to, in tower pressure after 0.8 mixing
Under 10kPa, the Temperature Distribution of reactive distillation column overhead to tower reactor is 43～60 DEG C, and catalyst is molecular sieve
Catalyst, air speed is 3h-1, tower reactor obtains aqueous 20% glycolic-aqueous mixtures, is sent to cold
But crystallize module, separate out ethanol acid crystal at a temperature of -3 DEG C, remaining Recycling Mother Solution returns reaction essence
Evaporate tower, the conversion ratio of methyl glycollate is 99%, selectivity 99%, the ethanol acid crystal response rate 95%.
【Embodiment 7】
By methyl glycollate and water in mass ratio 1:Deliver to reactive distillation column after 2 mixing, press 30kPa in tower
Under, the Temperature Distribution of reactive distillation column overhead to tower reactor is 63～79 DEG C, and catalyst is resin catalyst,
Air speed is 0.8h-1, tower reactor obtains aqueous 30% glycolic-aqueous mixtures, is sent to crystallisation by cooling
Module, separates out ethanol acid crystal at a temperature of -5 DEG C, and remaining Recycling Mother Solution returns reactive distillation column,
The conversion ratio of methyl glycollate is 99.9%, selectivity 99%, the ethanol acid crystal response rate 96%.
【Comparative example 1】
A kind of method is disclosed in CN104177250 embodiment 1：By methyl glycollate and water mole
Than for 1:10, catalyst adds tower reactor together, and catalyst is resinae catalyst, in 31.2W/kg
Heating load under, the pressure of the tower of 50kPa carry out reactive distillation, tower top obtains methanol, tower reactor obtains
Glycollic acid solution.Period need infinite reflux 20min after adjust again reflux ratio be 1 after continue reaction 4.5h,
Stop heating, the catalyst of tower reactor is reclaimed.
Can need for material and catalyst to inject tower reactor from said process, an operation cycle need to simultaneously
Will be through infinite reflux step it will be seen that said method be an intermittent process.And catalyst is located at
Tower reactor can increase tower reactor volume, can bring the long time of staying, and glycolic holds in such a situa-tion
Easily it is polymerized.
The present invention has following methods for similar raw material composition：By methyl glycollate with water in mass ratio
1:Deliver to reactive distillation column after 2 mixing, under tower pressure 20kPa, control reactive distillation column overhead to tower reactor
Temperature Distribution be 65～85 DEG C, catalyst be resin catalyst, be seated in the stripping section of rectifying column,
Reaction velocity is 2h-1, tower reactor obtains aqueous 20% glycolic-aqueous mixtures.Again by said mixture
Send into crystallization module and separate out ethanol acid crystal, Recycling Mother Solution returns reactive distillation column.
It can be found that through contrast：In the present invention it is achieved that continuous operation, permissible in a cycle
Stablize stable output product, need not move through infinite reflux step, may with more industrialization.Urge simultaneously
Agent is seated in stripping section and has great motility, realizes a broad space velocity range and is not subject to tower
The restriction that kettle amasss, mother solution continuously loops back in tower and reclaims glycolic further, improves the response rate.
Claims (10)
1. a kind of the method for ethanol acid crystal is prepared it is characterised in that comprising following step by methyl glycollate
Suddenly：
A) by methyl glycollate and water in mass ratio 1:(0.5～10) deliver to reactive distillation column after mixing,
Under conditions of tower presses the weight space velocity of 5kPa～85kPa, methyl glycollate to be no more than 5, tower reactor obtains
Aqueous 10%～50% glycolic-aqueous mixtures.
B) above-mentioned glycolic-aqueous mixtures are sent into crystallisation by cooling module, in -15～5 DEG C of temperature range
Interior crystallisation by cooling, separates out ethanol acid crystal, and remaining mother solution returns reactive distillation column simultaneously.
2. the method preparing ethanol acid crystal by methyl glycollate according to claim 1, it is special
Levy and be that reactive distillation column adopts solid acid catalyst.
3. the method preparing ethanol acid crystal by methyl glycollate according to claim 1, it is special
Levy and be that solid acid catalyst is at least one in resin and molecular sieve.
4. the method preparing ethanol acid crystal by methyl glycollate according to claim 1, it is special
Levy and be that catalyst is at least seated in stripping section.
5. the method preparing ethanol acid crystal by methyl glycollate according to claim 1, it is special
Levy and be that in reactive distillation column, temperature distribution range is 5～90 DEG C.
6. the method preparing ethanol acid crystal by methyl glycollate according to claim 1, it is special
Levy the glycolic-aqueous mixtures being that tower reactor obtains aqueous 10%～35%.
7. the method preparing ethanol acid crystal by methyl glycollate according to claim 1, it is special
Levy and be that in reactive distillation column, temperature is distributed as 40～90 DEG C.
8. the method preparing ethanol acid crystal by methyl glycollate according to claim 1, it is special
Levy and be that reaction velocity is 0.5～3.
9. the method preparing ethanol acid crystal by methyl glycollate according to claim 1, it is special
Levy and be that crystallization temperature is -10～5 DEG C.
10. the method that ethanol acid crystal is prepared by methyl glycollate according to claim 1, its
It is characterised by that crystallization temperature is -10～-3 DEG C.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201510541668.1A CN106478402A (en) | 2015-08-28 | 2015-08-28 | The method that ethanol acid crystal is prepared by methyl glycollate |
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| CN201510541668.1A CN106478402A (en) | 2015-08-28 | 2015-08-28 | The method that ethanol acid crystal is prepared by methyl glycollate |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109603907A (en) * | 2019-01-04 | 2019-04-12 | 丹东明珠特种树脂有限公司 | Cation resin catalyzing agent, preparation method and its catalytic applications that glycolic is prepared in methyl glycollate Hydrolyze method |
| CN109694318A (en) * | 2017-10-20 | 2019-04-30 | 中国石油化工股份有限公司 | The method for producing high purity ethanol acid |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104177250A (en) * | 2014-09-16 | 2014-12-03 | 上海华谊（集团）公司 | Process for producing glycollic acid from methyl glycolate |
| CN104829445A (en) * | 2015-05-04 | 2015-08-12 | 上海华谊（集团）公司 | Method for producing aqueous solution of glycolic acid |
-
2015
- 2015-08-28 CN CN201510541668.1A patent/CN106478402A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104177250A (en) * | 2014-09-16 | 2014-12-03 | 上海华谊（集团）公司 | Process for producing glycollic acid from methyl glycolate |
| CN104829445A (en) * | 2015-05-04 | 2015-08-12 | 上海华谊（集团）公司 | Method for producing aqueous solution of glycolic acid |
Non-Patent Citations (1)
| Title |
|---|
| 张超: "乙醇酸甲酯水解制乙醇酸工艺过程开发", 《中国优秀硕士学位论文全文数据库 工程科技I辑》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109694318A (en) * | 2017-10-20 | 2019-04-30 | 中国石油化工股份有限公司 | The method for producing high purity ethanol acid |
| CN109603907A (en) * | 2019-01-04 | 2019-04-12 | 丹东明珠特种树脂有限公司 | Cation resin catalyzing agent, preparation method and its catalytic applications that glycolic is prepared in methyl glycollate Hydrolyze method |
| CN109603907B (en) * | 2019-01-04 | 2024-03-26 | 丹东明珠特种树脂有限公司 | Preparation method of glycollic acid by catalytic hydrolysis of methyl glycolate |
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