CN103183610B - A kind of method from low-purity methyl acetate high-purity methyl acetate - Google Patents
A kind of method from low-purity methyl acetate high-purity methyl acetate Download PDFInfo
- Publication number
- CN103183610B CN103183610B CN201110446251.9A CN201110446251A CN103183610B CN 103183610 B CN103183610 B CN 103183610B CN 201110446251 A CN201110446251 A CN 201110446251A CN 103183610 B CN103183610 B CN 103183610B
- Authority
- CN
- China
- Prior art keywords
- methyl acetate
- low
- extraction
- tower
- purity
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention provides a kind of method by low alcohol low-purity methyl acetate high-purity methyl acetate, the method comprises the steps such as liquid-liquid extraction, azeotropic distillation and extracting rectifying, and be wherein the extraction agent of methyl acetate/methanol with water, acetic acid is the extraction agent of water.Further, for high alcohol low-purity methyl acetate, such as from the waste liquid (or waste gas) etc. that polyvinyl alcohol is produced, can after rough segmentation rectifying, aforesaid method be first adopted to purify again.The inventive method has the high and advantages such as steady quality of technical process is simple and direct, facility investment is few, stable operation is easily controlled, energy consumption is low, produce methyl acetate product purity.
Description
Technical field
The present invention relates to a kind of methyl acetate and reclaim the method for purifying or refining, more specifically, relate to a kind of method of high-purity methyl acetate from the mixture containing methyl acetate, first alcohol and water and other impurity of trace.
Background technology
Thick methyl acetate (purity about 75%, methyl alcohol about 25%) be mainly used in organic solvent required in resin, coating, ink, paint, Adhesive Manufacturing Process, or as oil extraction agent, be used in leatheroid manufacture view, but because in thick methyl esters, methanol content is high, its use field is restricted.
High purity methyl acetate has higher solvability and the feature of environmental protection, and partly or entirely can substitute the industrial solvent such as acetone, ethyl acetate in the industrial application such as process hides, solvent and thinner, its Application Areas is constantly expanded.Because the U.S. limits acetone solvent, Yi Shi Man released ritalin alternatively product in 2005, and market is day by day vigorous to the demand of methyl acetate.Methyl acetate can be obtained by esterification process, methyl alcohol hydroxylation method and the method such as acid anhydrides and methyl alcohol reaction.
Containing a large amount of methyl acetates in the waste liquid produced in polyvinyl alcohol production process.In general, the methyl acetate that 1 ton of polyvinyl alcohol will produce about 1.5 tons is often produced.Usually adopt the method for component distillation to be separated containing methyl acetate with methyl alcohol by methyl acetate with the alcohol liquid waste solution of methyl alcohol in polyvinyl alcohol production industry, azeotropic distillation column tower reactor methyl alcohol adopts traditional rectificating method by recycling after refining methanol; Component distillation column overhead methyl alcohol and methyl acetate azeotrope use water extracting rectifying further, extracting rectifying column overhead obtains containing the methyl acetate of a small amount of methyl alcohol and the azeotrope of water, be acetic acid and methyl alcohol with cation exchange resin as catalyst by methyl acetate hydrolysis, smart acetic acid and refined methanol is obtained again, recycling by after hydrolysate separating-purifying; Extractive distillation column tower reactor methanol aqueous solution adopts traditional rectificating method to be utilized by refining methanol Posterior circle.This process long flow path, high to the requirement of equipment, because methyl acetate hydrolysis rate is low, energy consumption is very big, the steam consumption about 5 tons that methyl acetate per ton reclaims and is hydrolyzed.And being acetic acid and the methyl alcohol of low value by the methyl acetate hydrolysis with higher commercial value, is also a kind of huge wasting of resources.
Because methyl acetate and methyl alcohol, water can form azeotrope, for this kind of containing methyl acetate, the liquid of first alcohol and water or gas, be difficult to be isolated with common rectifying or extracting process.In addition, produce in the process of methyl acetate at acetic acid and methanol esterification, same exist because methyl acetate and methyl alcohol are difficult to be separated the problem causing product purity on the low side.
The people such as Tsing-Hua University Chen Jian pass through component distillation, adsorptive distillation, the process such as condensing reflux and desorption and regeneration is from containing high purity methyl acetate (see CN1680267A) obtained the waste liquid of methyl acetate or gas, or by adopting extracting rectifying, liquid phase adsorption, alternating temperature purges, the processes such as desorption and regeneration obtain high purity methyl acetate (see CN1687002A), the method overcome the deficiency being difficult to be obtained by waste liquid or gas high purity methyl acetate with common rectifying or extracting process, but this method needs to use fixed bed or simulation moving-bed, there is complicated operation, investment is large, the problems such as the methyl acetate quality stability difference produced.
Nanjing Normal University turns round and look at the people such as positive osmanthus and makes extraction agent with the mixed solution of polyvalent alcohol (such as glycerine, ethylene glycol) and water, high purity methyl acetate (see CN101955427A, CN101898963A) is obtained from containing the waste liquid of methyl acetate by taking the method for multistage cross flow liquid-liquid extraction separating acetic acid methyl esters and methanol aqueous solution, but it is large to there is extraction agent recovery difficult in this method, and complex process, energy consumption are high, high in cost of production shortcoming.
Therefore be necessary to provide a kind of technical process is simple and direct, facility investment is few, stable operation is easily controlled, energy consumption is low, produce methyl acetate product purity high and the method for purification of stay-in-grade high purity methyl acetate.
Summary of the invention
The invention provides a kind of method from low-purity methyl acetate high-purity methyl acetate, the method comprises the steps:
(a) liquid-liquid extraction: low-purity methyl acetate is added by extraction tower bottom, from top overflow, with top-down extraction agent water counter current contact, top overflow obtains the raffinate (i.e. methyl acetate phase) of methyl acetate;
(b) azeotropic distillation: the raffinate of methyl acetate is delivered to azeotropy rectification column and carries out azeotropic distillation, tower top distillates dealcoholysis low-purity methyl acetate;
(c) extracting rectifying: azeotropy rectification column dealcoholysis low-purity methyl acetate is out sent to extractive distillation column, and add extraction agent from tower top, described extraction agent is acetic acid; Overhead extraction high purity methyl acetate, the mixed solution of tower reactor extraction agent and water carries out recovery and is extracted agent;
Wherein, described low-purity methyl acetate charging is low alcohol low-purity methyl acetate, and wherein methyl acetate massfraction is 70% ~ 98%, and methanol quality mark is 0.05% ~ 5%, and surplus is water and other impurity.
In the inventive method, in the charging of described low alcohol low-purity methyl acetate, methyl acetate massfraction can be 70% ~ 98%, preferably 87% ~ 98%, most preferably 90% ~ 98%; Methanol quality mark can be 0.05% ~ 5%, preferably 0.05% ~ 3%.
In the inventive method, the processing parameter of above-mentioned steps (a) liquid-liquid extraction is: the add-on of described extraction agent water and the volume ratio of low-purity methyl acetate inlet amount are (0.3 ~ 3.0): 1, preferably (0.5 ~ 2.5): 1; Extraction temperature is 5 ~ 50 DEG C, preferably 8 ~ 40 DEG C; Described extraction agent water is process water or deionized water, and described process water is decationizing water, and positively charged ion is calcium, magnesium ion mainly, preferred deionized water.
Impurity in above-mentioned low-purity methyl acetate charging is generally acetaldehyde, acetone, ethyl acetate, benzene, and its massfraction, generally lower than 0.015%, in above-mentioned steps (a), can remove partial impurities, removes acetaldehyde and acetone preferably.
In above-mentioned steps (a), tower reactor can adopt ordinary method to process containing the extraction liquid of methyl acetate and methyl alcohol, such as carries out rectification and purification respectively to methyl acetate and methyl alcohol.
The processing parameter of above-mentioned steps (b) azeotropic distillation is: backflow volume is than being (0.5 ~ 5.0): 1, preferably (0.6 ~ 3.5): 1; Bottom temperature is 57 ~ 135 DEG C, preferably 60 ~ 110 DEG C; Tower pressure (gauge pressure) is 0.001 ~ 0.22MPa, preferably 0.005 ~ 0.1MPa.
In above-mentioned steps (b), tower reactor waste water is outer row usually, or send sewage farm to process.
The processing parameter of above-mentioned steps (c) extracting rectifying is: backflow volume is than being (0.5 ~ 10.0): 1, preferably (0.6 ~ 5.0): 1; Described extraction agent and dealcoholysis low-purity methyl acetate feeding quantity volume ratio are (0.2 ~ 5.0): 1, preferably (0.5 ~ 3.0): 1; Bottom temperature is 90 ~ 160 DEG C, preferably 100 ~ 140 DEG C; Tower pressure (gauge pressure) is 0.001 ~ 0.2MPa, preferably 0.005 ~ 0.15MPa.
In above-mentioned steps (c), the mixed solution of tower reactor extraction agent and water adopts various ordinary method to reclaim and is extracted agent, carries out component distillation as added entrainer.
The inventive method is the mode by liquid-liquid extraction, azeotropic distillation and extracting rectifying, high-purity methyl acetate from the low alcohol low-purity methyl acetate mixture containing methyl acetate, first alcohol and water.Methyl acetate massfraction >=99.0% in the high purity produced, preferably >=99.8%, most preferably >=99.9%.
In a preferred embodiment, aforesaid method is also included in step (a ') the rectifying rough segmentation of the front increase of step (a): low-purity methyl acetate charging is first sent into methyl acetate rough segmentation tower, the extraction agent water added with tower top and the extraction liquid from step (a) carry out extracting rectifying; The low alcohol low-purity methyl acetate of overhead extraction is sent to the extraction tower process of step (a), and tower reactor does not reclaim further containing the methanol aqueous solution of methyl acetate and obtains methyl alcohol;
Wherein, described low-purity methyl acetate charging is high alcohol low-purity methyl acetate, and wherein methyl acetate massfraction is 5% ~ 98%, and methanol quality mark is 5% ~ 80%, and surplus is water and other impurity.
In this embodiment, the methyl acetate massfraction of described high alcohol low-purity methyl acetate can be 5% ~ 98%, preferably 10% ~ 80%, more preferably 10% ~ 50%, most preferably 15% ~ 35%; Methanol quality mark can be 5% ~ 80%, preferably 10% ~ 80%, more preferably 50% ~ 80%, most preferably 55% ~ 75%.
Produce waste liquid or waste gas for from polyvinyl alcohol, its each component composition is generally: methyl acetate massfraction 15% ~ 35%, methanol quality mark 55% ~ 75%, and all the other are water and other impurity, are especially applicable to adopting present method to carry out purification processes.
Described in above-mentioned steps (a ') rectifying rough segmentation, the add-on of extraction agent water and the volume ratio of low-purity methyl acetate inlet amount are (0.1 ~ 5.0): 1, preferably (0.5 ~ 3.0): 1; Backflow volume is than being (0.1 ~ 3.0): 1, and preferably (0.2 ~ 2.5): 1, described extraction agent water is process water or deionized water, preferred deionized water.
In this preferred method, by the mode of rectifying rough segmentation, liquid-liquid extraction, azeotropic distillation and extracting rectifying, high-purity methyl acetate from the high alcohol low-purity methyl acetate mixture containing methyl acetate, first alcohol and water.Methyl acetate massfraction >=99.00% in the high purity produced, preferably >=99.80%, most preferably >=99.90%.
The present invention, compared with existing extraction fractional distillation purifying acetic acid methyl esters, has the following advantages:
(1) adopt the liquid-liquid extraction agent using water as methyl acetate/methanol, overcome because methyl acetate is difficult to the difficulty that is separated with methanol azeotropic, high to methyl alcohol clearance, extraction agent is cheap and easy to get, and this process energy consumption is low.Compared with current extraction fractional distillation, adopt and use water as the extraction agent advantage that to have that technical process is simple and direct, facility investment is few, extraction agent high efficiency low cost, process consume energy low.
(2) adopt acetic acid to make the extraction agent of water, overcome the difficulty being difficult to because of methyl acetate and water azeotropic be separated, compared with the method making extraction agent purifying acetic acid methyl esters with spent glycol etc. known at present, in dehydration, there is the advantages such as efficient economy.
(3) extraction liquid containing methyl acetate and methyl alcohol that liquid-liquid extraction produces is delivered in methyl acetate rough segmentation tower and is made extraction agent, does not have the subsequent processes such as the recovery of extraction liquid.In existing extraction fractional distillation, after liquid-liquid extraction, extraction liquid needs the recycle of rectification process ability, this method needs high-temperature steam and energy consumption is high, extractant regeneration column overhead methanol purity is out only 95%, need be purified to 99.0% further even more than 99.8% just has actual industrial application value, and methanol purification process energy consumption is high.
CN1680267A report by processes such as component distillation, adsorptive distillation, condensing reflux and desorption and regenerations from containing high purity methyl acetate obtained the waste liquid of methyl acetate or gas, wherein in azeotropic process with the steam of methyl acetate/methanol or methyl acetate/methanol/water for charging, tower top azeotropic vaporization is directly sent to adsorptive distillation operation, and this object makes the material of charging form gaseous mixture.And the object of azeotropic distillation is remove portion water in the present invention.CN1687002A report obtains high purity methyl acetate by processes such as extracting rectifying, liquid phase adsorption, alternating temperature purging, desorption and regenerations, wherein makes extraction agent with the mixed solution of methyl acetate and process water in extracting rectifying process, its objective is except methyl alcohol.And extraction agent made by extracting rectifying process acetic acid in the present invention, this object dewaters.(make extraction agent with the mixed solution of methyl acetate and process water with existing extraction fractional distillation, see CN1687002A; CN101898963A is seen as extraction agent with the mixed solution of water and glycerine or ethylene glycol) to compare, the inventive method has the high and advantages such as steady quality of technical process is simple and direct, facility investment is few, stable operation is easily controlled, energy consumption is low, produce methyl acetate product purity.
Processing method provided by the invention be particularly useful for from polyvinyl alcohol production process produce containing the methyl acetate simply producing purity >=99.80% of high value the mixture of methyl acetate, first alcohol and water efficiently, be also applicable to the product purification of acetic acid and methanol esterification explained hereafter methyl acetate.
Accompanying drawing explanation
The simple process figure realizing a kind of preferred three-step approach high-purity methyl acetate of the present invention shown in Fig. 1.
The simple process figure realizing another preferred four step rule high-purity methyl acetate of the present invention shown in Fig. 2.
The implication identified in figure: A-liquid-liquid extraction tower, B-azeotropy rectification column, C-extractive distillation column; The low alcohol low-purity methyl acetate of 1-, 2-extraction agent deionized water, 3-contains the extraction liquid of methyl acetate and methyl alcohol, the raffinate of 4-methyl acetate, 5-dealcoholysis low-purity methyl acetate, 6-waste water, 7-extraction agent acetic acid, 8-high purity methyl acetate, the mixed solution of 9-extraction agent acetic acid and water; A '-methyl acetate rough segmentation tower, 1 '-Gao alcohol low-purity methyl acetate, 2 '-extraction agent deionized water, 3 '-methanol aqueous solution.
Embodiment
Below in conjunction with accompanying drawing 1, with the low alcohol low-purity methyl acetate liquid containing methyl acetate, first alcohol and water for charging, high-purity methyl acetate is described in detail.By method provided by the invention, through step (a) ~ step (c), high-purity methyl acetate.
This processing method comprises the steps:
A () is with reference to technical process shown in Fig. 1, low alcohol low-purity methyl acetate 1 is added from liquid-liquid extraction tower A bottom, extraction agent deionized water 2 adds by the middle part of extraction tower A, counter current contact is carried out with low alcohol low-purity methyl acetate 1, liquid-liquid extraction tower A top obtains the raffinate 4 of methyl acetate, and tower reactor is the extraction liquid 3 containing methyl acetate and methyl alcohol.The each controling parameters of liquid-liquid extraction: the volume ratio of extraction agent deionized water 2 add-on and low alcohol low-purity methyl acetate 1 is (0.3 ~ 3.0): 1, and extraction temperature is 5 ~ 50 DEG C.
B the raffinate 4 of methyl acetate is delivered to azeotropy rectification column B and is carried out azeotropic distillation by (), tower top distillates dealcoholysis low-purity methyl acetate 5 (i.e. the azeotrope of methyl acetate and water).The each controling parameters of azeotropic distillation: reflux ratio (volume ratio) is (0.5 ~ 5.0): 1; Bottom temperature is 57 ~ 135 DEG C; Tower pressure (gauge pressure) is 0.001 ~ 0.22MPa.The outer row of tower reactor waste water 6.
C the dealcoholysis low-purity methyl acetate 5 of azeotropy rectification column B top extraction adds by () in the middle part of extractive distillation column C, tower top adds extraction agent acetic acid 7 and carries out extracting rectifying, top of tower extraction high purity methyl acetate 8.The each processing parameter of extracting rectifying: reflux ratio (volume ratio) is (0.6 ~ 5.0): 1; Extraction agent acetic acid 7 and dealcoholysis low-purity methyl acetate 5 feeding quantity volume ratio are (0.5 ~ 3.0): 1; Bottom temperature is 90 ~ 160 DEG C, and tower pressure (gauge pressure) is 0.001 ~ 0.2MPa.The mixed solution 9 of tower reactor extraction extraction agent acetic acid and water, send extraction agent recovery tower to reclaim extraction agent acetic acid usually.
Below in conjunction with accompanying drawing 2, with the high alcohol low-purity methyl acetate liquid containing methyl acetate, first alcohol and water for charging, high-purity methyl acetate is described in detail.By method provided by the invention, through step (a ') and step (a) ~ step (c), high-purity methyl acetate.
But the high alcohol low-purity methyl acetate gas that the present invention is equally applicable to containing methyl acetate, first alcohol and water is charging.Namely in step (a '), improve the water yield that methyl acetate rough segmentation tower top adds, or by containing methyl acetate, first alcohol and water waste gas condensation or absorb with water, after changing the liquid containing methyl acetate, first alcohol and water into, by method provided by the invention, through step (a ') and step (a) ~ step (c), high-purity methyl acetate.
This processing method comprises the steps:
(a ') with reference to technical process shown in Fig. 2, high alcohol low-purity methyl acetate 1 ' is added from methyl acetate rough segmentation tower A ' middle part, tower top adds extraction agent deionized water 2 ' and the extraction liquid 3 containing methyl acetate and methyl alcohol from step (a), the low alcohol low-purity methyl acetate 1 of overhead extraction, the i.e. azeotrope of methyl acetate and water and a small amount of methyl alcohol.The each controling parameters of rectifying rough segmentation: extraction agent deionized water 2 ' add-on and high alcohol low-purity methyl acetate 1 ' feeding quantity volume ratio are (0.3 ~ 3.0): 1; Reflux ratio (volume ratio) is (0.2 ~ 2.0): 1.
A the low alcohol low-purity methyl acetate 1 of methyl acetate rough segmentation tower A ' top extraction adds from liquid-liquid extraction tower A bottom by (), extraction agent deionized water 2 adds by the middle part of extraction tower A, carry out counter current contact with low alcohol low-purity methyl acetate 1, liquid-liquid extraction tower A top obtains the raffinate 4 of methyl acetate; Tower reactor is the extraction liquid 3 containing methyl acetate and methyl alcohol, delivers in the methyl acetate rough segmentation tower A ' of step (a ') and makes extraction agent.The each controling parameters of liquid-liquid extraction: the volume ratio of extraction agent deionized water 2 add-on and low alcohol low-purity methyl acetate 1 is (0.3 ~ 3.0): 1, and extraction temperature is 5 ~ 50 DEG C.
B the raffinate 4 of methyl acetate is delivered to azeotropy rectification column B and is carried out azeotropic distillation by (), tower top distillates dealcoholysis low-purity methyl acetate 5 (i.e. the azeotrope of methyl acetate and water).The each controling parameters of azeotropic distillation: reflux ratio (volume ratio) is (0.5 ~ 5.0): 1; Bottom temperature is 57 ~ 135 DEG C; Tower pressure (gauge pressure) is 0.001 ~ 0.22MPa.The outer row of tower reactor waste water 6.
C the dealcoholysis low-purity methyl acetate 5 of azeotropy rectification column B top extraction adds by () in the middle part of extractive distillation column C, tower top adds extraction agent acetic acid 7 and carries out extracting rectifying, top of tower extraction high purity methyl acetate 8.The each processing parameter of extracting rectifying: reflux ratio (volume ratio) is (0.6 ~ 5.0): 1; Extraction agent acetic acid 7 and dealcoholysis low-purity methyl acetate 5 feeding quantity volume ratio are (0.5 ~ 3.0): 1; Bottom temperature is 100 ~ 140 DEG C, and tower pressure (gauge pressure) is 0.005 ~ 0.15MPa.The mixed solution 9 of tower reactor extraction extraction agent acetic acid and water, send extraction agent recovery tower to reclaim extraction agent acetic acid usually.
Describe in detail with the low alcohol low-purity methyl acetate liquid containing methyl acetate, first alcohol and water as charging three-step approach high-purity methyl acetate below by embodiment 1 ~ 6.
Described in detail with the high alcohol low-purity methyl acetate liquid containing methyl acetate, first alcohol and water as charging four step rule high-purity methyl acetate by embodiment 7 ~ 12.
embodiment 1
A () is with reference to technical process shown in Fig. 1, low alcohol low-purity methyl acetate 1 (wherein methyl acetate massfraction is 91.3%, methyl alcohol is 0.9%, all the other be water and other impurity) is added from extraction tower A bottom, deionized water 2 adds by the middle part of extraction tower A, counter-current extraction is carried out with low alcohol low-purity methyl acetate 1, extraction tower A top obtains the raffinate 4 of methyl acetate, and its constituent mass mark is methyl acetate 93.0%, methyl alcohol 0.053%.Tower reactor carries out rectification and purification recovery methyl acetate and methyl alcohol containing the extraction liquid 3 of methyl acetate and methyl alcohol.The each controling parameters of liquid-liquid extraction: the volume ratio of deionized water 2 add-on and low alcohol low-purity methyl acetate is 0.9: 1, and extraction temperature is 5 DEG C.
B the raffinate 4 of methyl acetate is delivered to azeotropy rectification column B and is carried out azeotropic distillation by (), tower top distillates dealcoholysis low-purity methyl acetate 5.The each controling parameters of azeotropic distillation: reflux ratio (volume ratio) is 0.5: 1; Bottom temperature is 63 DEG C; Tower pressure (gauge pressure) is 0.001MPa.The outer row of tower reactor waste water 6.
C the dealcoholysis low-purity methyl acetate 5 of azeotropy rectification column B top extraction adds by () in the middle part of extractive distillation column C, tower top adds extraction agent acetic acid 7 and carries out extracting rectifying, top of tower extraction high purity methyl acetate 8, wherein each constituent mass mark is: methyl acetate 99.91%, methyl alcohol 0.055%, water 0.022%, other impurity 0.013%.The each processing parameter of extracting rectifying: reflux ratio (volume ratio) is 0.6: 1; Acetic acid 7 and dealcoholysis low-purity methyl acetate 5 feeding quantity volume ratio are 1: 1; Bottom temperature is 95 DEG C, and tower pressure (gauge pressure) is 0.005MPa.The mixed solution 9 of tower reactor extraction acetic acid and water, send extraction agent recovery tower to reclaim acetic acid.
embodiment 2
A () is with reference to technical process shown in Fig. 1, low alcohol low-purity methyl acetate 1 (wherein methyl acetate massfraction is 87.5%, methyl alcohol is 1.95%, all the other be water and other impurity) is added from extraction tower A bottom, deionized water 2 adds by the middle part of extraction tower A, counter-current extraction is carried out with low alcohol low-purity methyl acetate 1, extraction tower A top obtains the raffinate 4 of methyl acetate, and its constituent mass mark is methyl acetate 92.5%, methyl alcohol 0.055%.Tower reactor carries out rectification and purification recovery methyl acetate and methyl alcohol containing the extraction liquid 3 of methyl acetate and methyl alcohol.The each controling parameters of liquid-liquid extraction: the volume ratio of deionized water 2 add-on and low alcohol low-purity methyl acetate is 1.7: 1, and extraction temperature is 10 DEG C.
B the raffinate 4 of methyl acetate is delivered to azeotropy rectification column B and is carried out azeotropic distillation by (), tower top distillates dealcoholysis low-purity methyl acetate 5.The each controling parameters of azeotropic distillation: reflux ratio (volume ratio) is 1: 1; Bottom temperature is 70 DEG C; Tower pressure (gauge pressure) is 0.022MPa.The outer row of tower reactor waste water 6.
C the dealcoholysis low-purity methyl acetate 5 of azeotropy rectification column B top extraction adds by () in the middle part of extractive distillation column C, tower top adds extraction agent acetic acid 7 and carries out extracting rectifying, top of tower extraction high purity methyl acetate 8, wherein each constituent mass mark is: methyl acetate 99.15%, methyl alcohol 0.065%, water 0.773%, other impurity 0.012%.The each processing parameter of extracting rectifying: reflux ratio (volume ratio) is 1.8: 1; Acetic acid and dealcoholysis low-purity methyl acetate feeding quantity volume ratio are 0.8: 1; Bottom temperature is 119 DEG C, and tower pressure (gauge pressure) is 0.035MPa.The mixed solution 9 of tower reactor extraction acetic acid and water, send extraction agent recovery tower to reclaim acetic acid.
embodiment 3
A () is with reference to technical process shown in Fig. 1, low alcohol low-purity methyl acetate 1 (wherein methyl acetate massfraction is 72.8%, methyl alcohol is 4.95%, all the other be water and other impurity) is added from extraction tower A bottom, deionized water 2 adds by the middle part of extraction tower A, counter-current extraction is carried out with low alcohol low-purity methyl acetate 1, extraction tower A top obtains the raffinate 4 of methyl acetate, and its constituent mass mark is methyl acetate 91.5%, methyl alcohol 0.14%.Tower reactor carries out rectification and purification recovery methyl acetate and methyl alcohol containing the extraction liquid 3 of methyl acetate and methyl alcohol.The each controling parameters of liquid-liquid extraction: the volume ratio of deionized water 2 add-on and low alcohol low-purity methyl acetate is 2.5: 1, and extraction temperature is 25 DEG C.
B the raffinate 4 of methyl acetate is delivered to azeotropy rectification column B and is carried out azeotropic distillation by (), tower top distillates dealcoholysis low-purity methyl acetate 5.The each controling parameters of azeotropic distillation: reflux ratio (volume ratio) is 3.0: 1; Bottom temperature is 112 DEG C; Tower pressure (gauge pressure) is 0.070MPa.The outer row of tower reactor waste water 6.
C the dealcoholysis low-purity methyl acetate 5 of azeotropy rectification column B top extraction adds by () in the middle part of extractive distillation column C, tower top adds extraction agent acetic acid 7 and carries out extracting rectifying, top of tower extraction high purity methyl acetate 8, wherein each constituent mass mark is: methyl acetate 99.71%, methyl alcohol 0.155%, water 0.127%, other impurity 0.008%.The each processing parameter of extracting rectifying: reflux ratio (volume ratio) is 1: 1; Extraction agent acetic acid 7 and dealcoholysis low-purity methyl acetate 5 feeding quantity volume ratio are 0.7: 1; Bottom temperature is 102 DEG C, and tower pressure (gauge pressure) is 0.006MPa.The mixed solution 9 of tower reactor extraction acetic acid and water, send extraction agent recovery tower to reclaim acetic acid.
embodiment 4
A () is with reference to technical process shown in Fig. 1, low alcohol low-purity methyl acetate 1 (wherein methyl acetate massfraction is 93.5%, methyl alcohol is 0.055%, all the other be water and other impurity) is added from extraction tower A bottom, deionized water 2 adds by the middle part of extraction tower A, counter-current extraction is carried out with low alcohol low-purity methyl acetate 1, extraction tower A top obtains the raffinate 4 of methyl acetate, and its constituent mass mark is methyl acetate 89.4%, methyl alcohol 0.025%.Tower reactor carries out rectification and purification recovery methyl acetate and methyl alcohol containing the extraction liquid 3 of methyl acetate and methyl alcohol.The each controling parameters of liquid-liquid extraction: the volume ratio of deionization 2 add-on and low alcohol low-purity methyl acetate is 0.4: 1, and extraction temperature is 35 DEG C.
B the raffinate 4 of methyl acetate is delivered to azeotropy rectification column B and is carried out azeotropic distillation by (), tower top distillates dealcoholysis low-purity methyl acetate 5.The each controling parameters of azeotropic distillation: reflux ratio (volume ratio) is 4: 1; Bottom temperature is 118 DEG C; Tower pressure (gauge pressure) is 0.080MPa.The outer row of tower reactor waste water 6.
C the dealcoholysis low-purity methyl acetate 5 of azeotropy rectification column B top extraction adds by () in the middle part of extractive distillation column C, tower top adds extraction agent acetic acid 7 and carries out extracting rectifying, top of tower extraction high purity methyl acetate 8, wherein each constituent mass mark is: methyl acetate 99.95%, methyl alcohol 0.028%, water 0.012%, other impurity 0.01%.The each processing parameter of extracting rectifying: reflux ratio (volume ratio) is 4.5: 1; Acetic acid 7 and dealcoholysis low-purity methyl acetate 5 feeding quantity volume ratio are 2.9: 1; Bottom temperature is 117 DEG C, and tower pressure (gauge pressure) is 0.020MPa.The mixed solution 9 of tower reactor extraction acetic acid and water, send extraction agent recovery tower to reclaim acetic acid.
embodiment 5
A () is with reference to technical process shown in Fig. 1, low alcohol low-purity methyl acetate 1 (wherein methyl acetate massfraction is 97.8%, methyl alcohol is 0.098%, all the other be water and other impurity) is added from extraction tower A bottom, deionized water 2 adds by the middle part of extraction tower A, counter-current extraction is carried out with low alcohol low-purity methyl acetate 1, extraction tower A top obtains the raffinate 4 of methyl acetate, and its constituent mass mark is methyl acetate 91.8%, methyl alcohol 0.018%.Tower reactor carries out rectification and purification recovery methyl acetate and methyl alcohol containing the extraction liquid 3 of methyl acetate and methyl alcohol.The each controling parameters of liquid-liquid extraction: the volume ratio of deionized water 2 add-on and low alcohol low-purity methyl acetate is 0.7: 1, and extraction temperature is 26 DEG C
B the raffinate 4 of methyl acetate is delivered to azeotropy rectification column B and is carried out azeotropic distillation by (), tower top distillates dealcoholysis low-purity methyl acetate 5.The each controling parameters of azeotropic distillation: reflux ratio (volume ratio) is 5: 1; Bottom temperature is 130 DEG C; Tower pressure (gauge pressure) is 0.180MPa.The outer row of tower reactor waste water 6.
C the dealcoholysis low-purity methyl acetate 5 of azeotropy rectification column B top extraction adds by () in the middle part of extractive distillation column C, tower top adds extraction agent acetic acid 7 and carries out extracting rectifying, top of tower extraction high purity methyl acetate 8, wherein each constituent mass mark is: methyl acetate 99.82%, methyl alcohol 0.02%, water 0.149%, other impurity 0.011%.The each processing parameter of extracting rectifying: reflux ratio (volume ratio) is 1.2: 1; Acetic acid 7 and dealcoholysis low-purity methyl acetate 5 feeding quantity volume ratio are 3: 1; Bottom temperature is 145 DEG C, and tower pressure (gauge pressure) is 0.130MPa.The mixed solution 9 of tower reactor extraction acetic acid and water, send extraction agent recovery tower to reclaim acetic acid.
embodiment 6
A () is with reference to technical process shown in Fig. 1, low alcohol low-purity methyl acetate 1 (wherein methyl acetate massfraction is 92.5%, methyl alcohol is 0.55%, all the other be water and other impurity) is added from extraction tower A bottom, deionized water 2 adds by the middle part of extraction tower A, counter-current extraction is carried out with low alcohol low-purity methyl acetate 1, extraction tower A top obtains the raffinate 4 of methyl acetate, and its constituent mass mark is methyl acetate 93.5%, methyl alcohol 0.06%.Tower reactor carries out rectification and purification recovery methyl acetate and methyl alcohol containing the extraction liquid 3 of methyl acetate and methyl alcohol.The each controling parameters of liquid-liquid extraction: the volume ratio of deionized water 2 add-on and low alcohol low-purity methyl acetate is 0.8: 1, and extraction temperature is 10 DEG C.
B the raffinate 4 of methyl acetate is delivered to azeotropy rectification column B and is carried out azeotropic distillation by (), tower top distillates dealcoholysis low-purity methyl acetate 5.The each controling parameters of azeotropic distillation: reflux ratio (volume ratio) is 2.0: 1; Bottom temperature is 82 DEG C; Tower pressure (gauge pressure) is 0.053MPa.The outer row of tower reactor waste water 6.
C the dealcoholysis low-purity methyl acetate 5 of azeotropy rectification column B top extraction adds by () in the middle part of extractive distillation column C, tower top adds acetic acid 7 and carries out extracting rectifying, top of tower extraction high purity methyl acetate 8, wherein each constituent mass mark is: methyl acetate 99.81%, methyl alcohol 0.065%, water 0.115%, other impurity 0.01%.The each processing parameter of extracting rectifying: reflux ratio (volume ratio) is 0.7: 1; Acetic acid and dealcoholysis low-purity methyl acetate feeding quantity volume ratio are 0.9: 1; Bottom temperature is 115 DEG C, and tower pressure (gauge pressure) is 0.015MPa.The mixed solution 9 of tower reactor extraction acetic acid and water, send extraction agent recovery tower to reclaim acetic acid.
Table 1 gathers the concrete technology parameter and product purity that give embodiment 1 ~ 6.
embodiment 7
(a ') with reference to technical process shown in Fig. 2, raw material is that 1000 kilograms high alcohol low-purity methyl acetate 1 ' (wherein the massfraction of main ingredient is: methyl acetate 13.2%, methyl alcohol 72.3%) add from methyl acetate rough segmentation tower A ' middle part, tower top adds deionized water 2 ' and the extraction liquid 3 from step (a), the low alcohol low-purity methyl acetate 1 of overhead extraction, wherein the massfraction of each component is: methyl acetate 92.3%, methyl alcohol 0.53%, all the other are water and other impurity.The each controling parameters of rectifying rough segmentation: deionized water 2 ' add-on and high alcohol low-purity methyl acetate 1 ' feeding quantity volume ratio are 2.9: 1; Reflux ratio (volume ratio) is 0.5: 1.
A the low alcohol low-purity methyl acetate 1 of methyl acetate rough segmentation tower A ' top extraction adds from extraction tower A bottom by (), deionized water 2 adds by the middle part of extraction tower A, counter-current extraction is carried out with low alcohol low-purity methyl acetate 1, extraction tower A top obtains the raffinate 4 of methyl acetate, and its constituent mass mark is methyl acetate 92.8%, methyl alcohol 0.04%.Tower reactor is delivered in the methyl acetate rough segmentation tower A ' of step (a ') containing the extraction liquid 3 of methyl acetate and methyl alcohol and is made extraction agent.The each controling parameters of liquid-liquid extraction: the volume ratio of deionized water 2 add-on and low alcohol low-purity methyl acetate 1 is 0.7: 1, and extraction temperature is 10 DEG C.
B the raffinate 4 of methyl acetate is delivered to azeotropy rectification column B and is carried out azeotropic distillation by (), tower top distillates dealcoholysis low-purity methyl acetate 5, and its constituent mass mark is: methyl acetate 96.6%, methyl alcohol 0.042%.The each controling parameters of azeotropic distillation: reflux ratio (volume ratio) is 0.9: 1; Bottom temperature is 75 DEG C; Tower pressure (gauge pressure) is 0.025MPa.The outer row of tower reactor waste water 6.
C the dealcoholysis low-purity methyl acetate 5 of azeotropy rectification column B top extraction adds by () in the middle part of extractive distillation column C, tower top adds extraction agent acetic acid 7 and carries out extracting rectifying, top of tower extraction high purity methyl acetate 8, wherein the massfraction of methyl acetate is 99.81%, methyl alcohol 0.045%, water 0.137%, other impurity 0.008%.The each processing parameter of extracting rectifying: reflux ratio (volume ratio) is 0.8: 1; Acetic acid 7 and dealcoholysis low-purity methyl acetate 5 feeding quantity volume ratio are 0.5: 1; Bottom temperature is 115 DEG C, and tower pressure (gauge pressure) is 0.035MPa.The mixed solution 9 of tower reactor extraction acetic acid and water, send extraction agent recovery tower to reclaim acetic acid.
embodiment 8
(a ') with reference to technical process shown in Fig. 2, raw material is that 1000 kilograms high alcohol low-purity methyl acetate 1 ' (produce waste liquid from polyvinyl alcohol, wherein the massfraction of main ingredient is: methyl acetate 18.7%, methyl alcohol 68.4%) add from methyl acetate rough segmentation tower A ' middle part, tower top adds deionized water 2 ' and the extraction liquid 3 from step (a), the low alcohol low-purity methyl acetate 1 of overhead extraction, wherein the massfraction of each component is: methyl acetate 91.4%, methyl alcohol 0.058%, all the other are water and other impurity.The each controling parameters of rectifying rough segmentation: deionized water 2 ' add-on and high alcohol low-purity methyl acetate 1 ' feeding quantity volume ratio are 1.8: 1; Reflux ratio (volume ratio) is 1: 1.
A the low alcohol low-purity methyl acetate 1 of methyl acetate rough segmentation tower A ' top extraction adds from extraction tower A bottom by (), deionized water 2 adds by the middle part of extraction tower A, counter-current extraction is carried out with low alcohol low-purity methyl acetate 1, extraction tower A top obtains the raffinate 4 of methyl acetate, and its constituent mass mark is methyl acetate 92.4%, methyl alcohol 0.022%.Tower reactor is delivered in the methyl acetate rough segmentation tower A ' of step (a ') containing the extraction liquid 3 of methyl acetate and methyl alcohol and is made extraction agent.The each controling parameters of liquid-liquid extraction: the volume ratio of deionized water 2 add-on and low alcohol low-purity methyl acetate 1 is 0.4: 1, and extraction temperature is 15 DEG C.
B the raffinate 4 of methyl acetate is delivered to azeotropy rectification column B and is carried out azeotropic distillation by (), tower top distillates dealcoholysis low-purity methyl acetate 5, and its constituent mass mark is: methyl acetate 95.3%, methyl alcohol 0.023%.The each controling parameters of azeotropic distillation: reflux ratio (volume ratio) is 2: 1; Bottom temperature is 90 DEG C; Tower pressure (gauge pressure) is 0.048MPa.The outer row of tower reactor waste water 6.
C the dealcoholysis low-purity methyl acetate 5 of azeotropy rectification column B top extraction adds by () in the middle part of extractive distillation column C, tower top adds extraction agent acetic acid 7 and carries out extracting rectifying, top of tower extraction high purity methyl acetate 8, wherein the massfraction of methyl acetate be 99.90%, methyl alcohol 0.024%, water 0.066%, other impurity 0.01%.The each processing parameter of extracting rectifying: reflux ratio (volume ratio) is 1.5: 1; Acetic acid 7 and dealcoholysis low-purity methyl acetate 5 feeding quantity volume ratio are 1: 1; Bottom temperature is 119 DEG C, and tower pressure (gauge pressure) is 0.055MPa.The mixed solution 9 of tower reactor extraction acetic acid and water, send extraction agent recovery tower to reclaim acetic acid.
embodiment 9
(a ') with reference to technical process shown in Fig. 2, raw material is that 1000 kilograms high alcohol low-purity methyl acetate 1 ' (produce waste liquid from polyvinyl alcohol, wherein the massfraction of main ingredient is: methyl acetate 33.4%, methyl alcohol 55.2%) add from methyl acetate rough segmentation tower A ' middle part, tower top adds deionized water 2 ' and the extraction liquid 3 from step (a), the low alcohol low-purity methyl acetate 1 of overhead extraction, wherein the massfraction of each component is: methyl acetate 85.5%, methyl alcohol 1.87%, all the other are water and other impurity.The each controling parameters of rectifying rough segmentation: deionized water 2 ' add-on and high alcohol low-purity methyl acetate 1 ' feeding quantity volume ratio are 2.0: 1; Reflux ratio (volume ratio) is 1.5: 1.
A the low alcohol low-purity methyl acetate 1 of methyl acetate rough segmentation tower A ' top extraction adds from extraction tower A bottom by (), deionized water 2 adds by the middle part of extraction tower A, counter-current extraction is carried out with low alcohol low-purity methyl acetate 1, extraction tower A top obtains the raffinate 4 of methyl acetate, and its constituent mass mark is methyl acetate 92.2%, methyl alcohol 0.047%.Tower reactor is delivered in the methyl acetate rough segmentation tower A ' of step (a ') containing the extraction liquid 3 of methyl acetate and methyl alcohol and is made extraction agent.The each controling parameters of liquid-liquid extraction: the volume ratio of deionized water 2 add-on and low alcohol low-purity methyl acetate 1 is 1.9: 1, and extraction temperature is 20 DEG C.
B the raffinate 4 of methyl acetate is delivered to azeotropy rectification column B and is carried out azeotropic distillation by (), tower top distillates dealcoholysis low-purity methyl acetate 5, and its constituent mass mark is: methyl acetate 96.4%, methyl alcohol 0.048%.The each controling parameters of azeotropic distillation: reflux ratio (volume ratio) is 2.5: 1; Bottom temperature is 105 DEG C; Tower pressure (gauge pressure) is 0.065MPa.The outer row of tower reactor waste water 6.
C the dealcoholysis low-purity methyl acetate 5 of azeotropy rectification column B top extraction adds by () in the middle part of extractive distillation column C, tower top adds extraction agent acetic acid 7 and carries out extracting rectifying, top of tower extraction high purity methyl acetate 8, wherein the massfraction of methyl acetate be 99.39%, methyl alcohol 0.05%, water 0.55%, other impurity 0.01%.The each processing parameter of extracting rectifying: reflux ratio (volume ratio) is 2: 1; Acetic acid 7 and dealcoholysis low-purity methyl acetate 5 feeding quantity volume ratio are 1.5: 1; Bottom temperature is 122 DEG C, and tower pressure (gauge pressure) is 0.068MPa.Tower reactor extraction acetic acid 9, send extraction agent recovery tower to reclaim acetic acid.
embodiment 10
(a ') with reference to technical process shown in Fig. 2, raw material is that 1000 kilograms high alcohol low-purity methyl acetate 1 ' (wherein the massfraction of main ingredient is: methyl acetate 52.3%, methyl alcohol 35.2%) add from methyl acetate rough segmentation tower A ' middle part, tower top adds deionized water 2 ' and the extraction liquid 3 from step (a), the low alcohol low-purity methyl acetate 1 of overhead extraction, wherein the massfraction of each component is: methyl acetate 70.8%, methyl alcohol 4.75%, all the other are water and other impurity.The each controling parameters of rectifying rough segmentation: deionized water 2 ' add-on and high alcohol low-purity methyl acetate 1 ' feeding quantity volume ratio are 0.7: 1; Reflux ratio (volume ratio) is 1.3: 1.
A the low alcohol low-purity methyl acetate 1 of methyl acetate rough segmentation tower A ' top extraction adds from extraction tower A bottom by (), deionized water 2 adds by the middle part of extraction tower A, counter-current extraction is carried out with low alcohol low-purity methyl acetate 1, extraction tower A top obtains the raffinate 4 of methyl acetate, and its constituent mass mark is methyl acetate 92.0%, methyl alcohol 0.042%.Tower reactor is delivered in the methyl acetate rough segmentation tower A ' of step (a ') containing the extraction liquid 3 of methyl acetate and methyl alcohol and is made extraction agent.The each controling parameters of liquid-liquid extraction: the volume ratio of deionized water 2 add-on and low alcohol low-purity methyl acetate 1 is 2.2: 1, and extraction temperature is 30 DEG C.
B the raffinate 4 of methyl acetate is delivered to azeotropy rectification column B and is carried out azeotropic distillation by (), tower top distillates dealcoholysis low-purity methyl acetate 5, and its constituent mass mark is: methyl acetate 96.7%, methyl alcohol 0.043%.The each controling parameters of azeotropic distillation: reflux ratio (volume ratio) is 3: 1; Bottom temperature is 108 DEG C; Tower pressure (gauge pressure) is 0.078MPa.The outer row of tower reactor waste water 6.
C the dealcoholysis low-purity methyl acetate 5 of azeotropy rectification column B top extraction adds by () in the middle part of extractive distillation column C, tower top adds extraction agent acetic acid 7 and carries out extracting rectifying, top of tower extraction high purity methyl acetate 8, wherein the massfraction of methyl acetate be 99.73%, methyl alcohol 0.050%, water 0.209%, other impurity 0.011%.The each processing parameter of extracting rectifying: reflux ratio (volume ratio) is 3.5: 1; Acetic acid 7 and dealcoholysis low-purity methyl acetate 5 feeding quantity volume ratio are 1.8: 1; Bottom temperature is 125 DEG C, and tower pressure (gauge pressure) is 0.082MPa.The mixed solution 9 of tower reactor extraction acetic acid and water, send extraction agent recovery tower to reclaim acetic acid.
embodiment 11
(a ') with reference to technical process shown in Fig. 2, raw material is that 1000 kilograms high alcohol low-purity methyl acetate 1 ' (produce waste liquid from polyvinyl alcohol, wherein the massfraction of main ingredient is: methyl acetate 20.1%, methyl alcohol 65.6%) add from methyl acetate rough segmentation tower A ' middle part, tower top adds deionized water 2 ' and the extraction liquid 3 from step (a), the low alcohol low-purity methyl acetate 1 of overhead extraction, wherein the massfraction of each component is: methyl acetate 92.2%, methyl alcohol 0.094%, all the other are water and other impurity.The each controling parameters of rectifying rough segmentation: deionized water 2 ' add-on and high alcohol low-purity methyl acetate 1 ' feeding quantity volume ratio are 2.5: 1; Reflux ratio (volume ratio) is 2: 1.
A the low alcohol low-purity methyl acetate 1 of methyl acetate rough segmentation tower A ' top extraction adds from extraction tower A bottom by (), deionized water 2 adds by the middle part of extraction tower A, counter-current extraction is carried out with low alcohol low-purity methyl acetate 1, extraction tower A top obtains the raffinate 4 of methyl acetate, and its constituent mass mark is methyl acetate 91.4%, methyl alcohol 0.045%.Tower reactor is delivered in the methyl acetate rough segmentation tower A ' of step (a ') containing the extraction liquid 3 of methyl acetate and methyl alcohol and is made extraction agent.The each controling parameters of liquid-liquid extraction: the volume ratio of deionized water 2 add-on and low alcohol low-purity methyl acetate 1 is 0.5: 1, and extraction temperature is 35 DEG C
B the raffinate 4 of methyl acetate is delivered to azeotropy rectification column B and is carried out azeotropic distillation by (), tower top distillates dealcoholysis low-purity methyl acetate 5, and its constituent mass mark is: methyl acetate 96.5%, methyl alcohol 0.05%.The each controling parameters of azeotropic distillation: reflux ratio (volume ratio) is 3.5: 1; Bottom temperature is 115 DEG C; Tower pressure (gauge pressure) is 0.085MPa.The outer row of tower reactor waste water 6.
C the dealcoholysis low-purity methyl acetate 5 of azeotropy rectification column B top extraction adds by () in the middle part of extractive distillation column C, tower top adds extraction agent acetic acid 7 and carries out extracting rectifying, top of tower extraction high purity methyl acetate 8, wherein the massfraction of methyl acetate be 99.92%, methyl alcohol 0.052%, water 0.016%, other impurity 0.012%.The each processing parameter of extracting rectifying: reflux ratio (volume ratio) is 4: 1; Acetic acid 7 and dealcoholysis low-purity methyl acetate 5 feeding quantity volume ratio are 2: 1; Bottom temperature is 138 DEG C, and tower pressure (gauge pressure) is 0.106MPa.The mixed solution 9 of tower reactor extraction acetic acid and water, send extraction agent recovery tower to reclaim acetic acid.
embodiment 12
(a ') with reference to technical process shown in Fig. 2, raw material is that 1000 kilograms high alcohol low-purity methyl acetate 1 ' (wherein the massfraction of main ingredient is: methyl acetate 75.1%, methyl alcohol 12.8%) add from methyl acetate rough segmentation tower A ' middle part, tower top adds deionized water 2 ' and the extraction liquid 3 from step (a), the low alcohol low-purity methyl acetate 1 of overhead extraction, wherein the massfraction of each component is: methyl acetate 76.4%, methyl alcohol 4.87%, all the other are water and other impurity.The each controling parameters of rectifying rough segmentation: deionized water 2 ' add-on and high alcohol low-purity methyl acetate 1 ' feeding quantity volume ratio are 0.3: 1; Reflux ratio (volume ratio) is 1.1: 1.
A the low alcohol low-purity methyl acetate 1 of methyl acetate rough segmentation tower A ' top extraction adds from extraction tower A bottom by (), deionized water 2 adds by the middle part of extraction tower A, counter-current extraction is carried out with low alcohol low-purity methyl acetate 1, extraction tower A top obtains the raffinate 4 of methyl acetate, and its constituent mass mark is methyl acetate 92.1%, methyl alcohol 0.128%.Tower reactor is delivered in the methyl acetate rough segmentation tower A ' of step (a ') containing the extraction liquid 3 of methyl acetate and methyl alcohol and is made extraction agent.The each controling parameters of liquid-liquid extraction: the volume ratio of deionized water 2 add-on and low alcohol low-purity methyl acetate 1 is 1: 1, and extraction temperature is 17 DEG C.
B the raffinate 4 of methyl acetate is delivered to azeotropy rectification column B and is carried out azeotropic distillation by (), tower top distillates dealcoholysis low-purity methyl acetate 5, and its constituent mass mark is: methyl acetate 96.3%, methyl alcohol 0.134%.The each controling parameters of azeotropic distillation: reflux ratio (volume ratio) is 2.2: 1; Bottom temperature is 95 DEG C; Tower pressure (gauge pressure) is 0.050MPa.The outer row of tower reactor waste water 6.
C the dealcoholysis low-purity methyl acetate 5 of azeotropy rectification column B top extraction adds by () in the middle part of extractive distillation column C, tower top adds extraction agent acetic acid 7 and carries out extracting rectifying, top of tower extraction high purity methyl acetate 8, wherein the massfraction of methyl acetate be 99.82%, methyl alcohol 0.135%, water 0.034%, other impurity 0.011%.The each processing parameter of extracting rectifying: reflux ratio (volume ratio) is 1.7: 1; Acetic acid 7 and dealcoholysis low-purity methyl acetate 5 feeding quantity volume ratio are 1.1: 1; Bottom temperature is 119 DEG C, and tower pressure (gauge pressure) is 0.058MPa.The mixed solution 9 of tower reactor extraction acetic acid and water, send extraction agent recovery tower to reclaim acetic acid.
Table 2 gathers the concrete technology parameter and product purity that give embodiment 7 ~ 12.
Three-step approach high-purity methyl acetate under table 1 different technical parameters
Four step rule high-purity methyl acetate under table 2 different technical parameters
Claims (14)
1. from a method for low-purity methyl acetate high-purity methyl acetate, it is characterized in that, the method comprises the steps:
(a) liquid-liquid extraction: low-purity methyl acetate charging is added by extraction tower bottom, from top overflow, with top-down extraction agent water counter current contact, top overflow obtains the raffinate of methyl acetate;
(b) azeotropic distillation: the raffinate of methyl acetate is delivered to azeotropy rectification column and carries out azeotropic distillation, tower top distillates dealcoholysis low-purity methyl acetate;
(c) extracting rectifying: azeotropy rectification column dealcoholysis low-purity methyl acetate is out sent to extractive distillation column, and add extraction agent from tower top, described extraction agent is acetic acid; Overhead extraction high purity methyl acetate, the mixed solution of tower reactor extraction agent and water carries out recovery and is extracted agent;
Wherein, described low-purity methyl acetate charging is low alcohol low-purity methyl acetate, and wherein methyl acetate massfraction is 70% ~ 98%, and methanol quality mark is 0.05% ~ 5%, and surplus is water and other impurity;
Described method is also included in step (a ') the rectifying rough segmentation of the front increase of step (a): low-purity methyl acetate charging is first sent into methyl acetate rough segmentation tower, the extraction agent water added with tower top and the extraction liquid from step (a) carry out extracting rectifying; The low alcohol low-purity methyl acetate of overhead extraction is sent to the extraction tower process of step (a), and tower reactor does not reclaim further containing the methanol aqueous solution of methyl acetate and obtains methyl alcohol;
Wherein, described low-purity methyl acetate charging is high alcohol low-purity methyl acetate, and wherein methyl acetate massfraction is 5% ~ 98%, and methanol quality mark is 5% ~ 80%, and surplus is water and other impurity.
2. method according to claim 1, it is characterized in that, the add-on of extraction agent water described in step (a) liquid-liquid extraction and the volume ratio of low-purity methyl acetate inlet amount are (0.3 ~ 3.0): 1, extraction temperature is 5 ~ 50 DEG C, and described extraction agent water is process water or deionized water.
3. method according to claim 2, it is characterized in that, the add-on of extraction agent water described in step (a) liquid-liquid extraction and the volume ratio of low-purity methyl acetate inlet amount are (0.5 ~ 2.5): 1, extraction temperature is 8 ~ 40 DEG C, and described extraction agent water is deionized water.
4. method according to claim 1, is characterized in that, in step (b) azeotropic distillation, backflow volume is than being (0.5 ~ 5.0): 1, and bottom temperature is 57 ~ 135 DEG C, and tower pressure gauge pressure is 0.001 ~ 0.22MPa.
5. method according to claim 4, is characterized in that, in step (b) azeotropic distillation, backflow volume is than being (0.6 ~ 3.5): 1, and bottom temperature is 60 ~ 110 DEG C, and tower pressure gauge pressure is 0.005 ~ 0.1MPa.
6. method according to claim 1, it is characterized in that, in step (c) extracting rectifying, backflow volume is than being (0.5 ~ 10.0): 1, described extraction agent and dealcoholysis low-purity methyl acetate feeding quantity volume ratio are (0.2 ~ 5.0): 1, bottom temperature is 90 ~ 160 DEG C, and tower pressure gauge pressure is 0.001 ~ 0.2MPa.
7. method according to claim 6, it is characterized in that, in step (c) extracting rectifying, backflow volume is than being (0.6 ~ 5.0): 1, described extraction agent and dealcoholysis low-purity methyl acetate feeding quantity volume ratio are (0.5 ~ 3.0): 1, bottom temperature is 100 ~ 140 DEG C, and tower pressure gauge pressure is 0.005 ~ 0.15MPa.
8. method according to claim 1, is characterized in that, in described low alcohol low-purity methyl acetate, methyl acetate massfraction is 87% ~ 98%, and methanol quality mark is 0.05% ~ 3%.
9. method according to claim 1, it is characterized in that, described in step (a ') rectifying rough segmentation, the add-on of extraction agent water and the volume ratio of low-purity methyl acetate inlet amount are (0.1 ~ 5.0): 1, backflow volume is than being (0.1 ~ 3.0): 1, and described extraction agent water is process water or deionized water.
10. method according to claim 9, it is characterized in that, described in step (a '), the add-on of extraction agent water and the volume ratio of low-purity methyl acetate inlet amount are (0.5 ~ 3.0): 1, backflow volume is than being (0.2 ~ 2.5): 1, and described extraction agent water is deionized water.
11. methods according to claim 1, is characterized in that, in described high alcohol low-purity methyl acetate, methyl acetate massfraction is 15% ~ 35%, methanol quality mark is 55% ~ 75%, and surplus is water and other impurity.
12. methods according to claim 1, is characterized in that, described high alcohol low-purity methyl acetate produces waste liquid or waste gas from polyvinyl alcohol.
13. methods according to any one of claim 1 ~ 12, is characterized in that, methyl acetate massfraction >=99.80% in described high purity methyl acetate.
14. methods according to any one of claim 1 ~ 12, is characterized in that, methyl acetate massfraction >=99.90% in described high purity methyl acetate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110446251.9A CN103183610B (en) | 2011-12-28 | 2011-12-28 | A kind of method from low-purity methyl acetate high-purity methyl acetate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110446251.9A CN103183610B (en) | 2011-12-28 | 2011-12-28 | A kind of method from low-purity methyl acetate high-purity methyl acetate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103183610A CN103183610A (en) | 2013-07-03 |
| CN103183610B true CN103183610B (en) | 2015-08-12 |
Family
ID=48675089
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201110446251.9A Active CN103183610B (en) | 2011-12-28 | 2011-12-28 | A kind of method from low-purity methyl acetate high-purity methyl acetate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103183610B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR3077994B1 (en) * | 2018-02-22 | 2020-02-28 | IFP Energies Nouvelles | SELECTIVE SEPARATION OF IMPURITIES PRESENT IN A HYDROALCOHOLIC SECTION BY RECYCLING IN A LIQUID-LIQUID EXTRACTION COLUMN |
| CN117756632A (en) * | 2023-12-18 | 2024-03-26 | 珠海谦信新材料有限公司 | Purification method for synthesizing methyl acetate by esterification reaction |
-
2011
- 2011-12-28 CN CN201110446251.9A patent/CN103183610B/en active Active
Non-Patent Citations (2)
| Title |
|---|
| 副产品中萃取精馏制备高纯度醋酸甲酯探索;李俊岭 等;《化工生产与技术》;20111025;第18卷(第5期);第34-36页 * |
| 醋酸甲酯-甲醇-水的复合盐萃取分离研究;杨东杰 等;《高校化学工程学报》;20070415;第21卷(第2期);第239-244页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103183610A (en) | 2013-07-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101811965B (en) | Process for separating and recovering butyl acetate and butyl alcohol in wastewater by using azeotropic rectification | |
| CN106220532B (en) | A kind of method of separation of extractive distillation acetonitrile and triethylamine | |
| CN107032966B (en) | Method for separating propylene glycol methyl ether and water by liquid-liquid extraction-extractive distillation | |
| CN103435445A (en) | Method for separating mixture of ethanol alcohol and water | |
| CN103664522B (en) | There is the method for the integrated separating ethylene glycol of heat and 1,2-butyleneglycol | |
| CN103827072A (en) | Method for recovering acetic acid | |
| CN105503522A (en) | Recycling and refining device for methylbenzene-methyl alcohol/ethyl alcohol and separating method | |
| CN106588828B (en) | A kind of THF rectifying waste liquid process for separation and purification | |
| CN103012332B (en) | Use the method for packing tower distillation separation of tetrahydrofuran-methanol-water solvent slop | |
| CN107137949B (en) | Extraction and rectification partition plate tower device and method for dehydrating low-concentration isopropanol solution | |
| CN108689812B (en) | Method for simultaneously removing methanol and water by ionic liquid extractive distillation | |
| CN101830788A (en) | Method for separating azeotropic mixture of ethyl methyl ketone and water through variable-pressure rectification | |
| CN109534998B (en) | Energy-saving process for separating ethyl acetate-ethanol by pressure swing distillation with side extraction | |
| CN104803870A (en) | Method for extracting and recovering amide from aqueous solution | |
| CN105001055B (en) | Based on mixed solvent as extractant isopropanol acetonitrile azeotropic mixture distillation and separation method | |
| CN103183610B (en) | A kind of method from low-purity methyl acetate high-purity methyl acetate | |
| CN103772185B (en) | Device and method for removing moisture and heteroacids in acetic acid | |
| CN113651693A (en) | Equipment and method for producing ethyl acetate by using ionic liquid dehydration technology | |
| CN105669445B (en) | The production technology of ethyl acetate | |
| CN103833537B (en) | Absorption and refining method for high-purity methylacrolein | |
| CN210134039U (en) | Battery grade dimethyl carbonate refining plant | |
| CN209778702U (en) | Device for separating n-butyl alcohol and n-butyl ether by extraction and rectification processes | |
| CN104418734B (en) | From the industrial by-product of terephthalic acid (TPA), directly extract the method for high-purity methyl acetate | |
| CN202336224U (en) | Azeotropic distillation system for mixture of carbinol and tetrahydrofuran | |
| CN102219689A (en) | Method for producing dimethyl terephthalate (DMT) |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |