CN105481713A - Method and apparatus for recovering N-t-butyl acrylamide - Google Patents
Method and apparatus for recovering N-t-butyl acrylamide Download PDFInfo
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- CN105481713A CN105481713A CN201410472828.7A CN201410472828A CN105481713A CN 105481713 A CN105481713 A CN 105481713A CN 201410472828 A CN201410472828 A CN 201410472828A CN 105481713 A CN105481713 A CN 105481713A
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- butyl acrylamide
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- waste residue
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Abstract
The present invention relates to a method for recovering N-t-butyl acrylamide. The method comprises: mixing waste residue obtained after 2-acrylamide-2-methylpropanesulfonic acid production, a solvent and an adsorbent, filtering, carrying out vacuum heating on the filtrate, continuously heating the remaining solid after evaporating the solvent so as to sublime the remaining solid, and recovering the sublimed product to obtain the N-t-butyl acrylamide, wherein the vacuum heating is performed at a temperature of 40-120 DEG C under a pressure of 1-50k Pa, and the purity of the recovered N-t-butyl acrylamide is more than or equal to 99.5%. The present invention further provides a recovery apparatus for the method, wherein the recovery apparatus comprises a heatable separation container for heating the waste residue obtained after the 2-acrylamide-2-methylpropanesulfonic acid production, a temperature-adjustable collection container for collecting the sublimed N-t-butyl acrylamide, and a vacuum system.
Description
Technical field
The present invention relates to a kind of method reclaiming N tert butyl acrylamide from the waste residue of production tert-butyl acrylamide sulfonate, and corresponding retrieving arrangement.
Background technology
N tert butyl acrylamide (molecular formula C
7h
13nO, English name N-tert-Butylacrylamide) be a kind of hydrophobic monomer with amide group, may be used for the synthesis of hydrophobic associated water-soluble polymer.Hydrophobic associated water-soluble polymer to refer on Water-soluble Polymer Molecules chain with a small amount of hydrophobic grouping, makes SOLUTION PROPERTIES show unique rheological property, because it has hydrophilic segment and hydrophobic grouping concurrently, can regard a polymeric surfactant as.The microcell that hydrophobic grouping is formed can regard the micella that tensio-active agent is formed as, so there is micelle-forming concentration at certain polymer concentration range, during higher than this concentration, the hydrophobic microcell that hydrophobic grouping is formed facilitates the molecular chain aggregate of a super large, there is dynamic physical cross-linked network structure, increase the hydrodynamic volume of polymkeric substance, thus significantly improve soltion viscosity.Owing to being physical cross-linked network structure, so hydrophobic microcell is destroyed under high shear forces, soltion viscosity declines, after shearing action is eliminated, hydrophobic microcell is formed again, viscosity recovery, and general high molecular polymer irreversible mechano-degradation at high shear rates does not occur.Owing to there being the rheological property of this uniqueness, hydrophobic comprehensive polymkeric substance is used widely in a lot of fields, as in pharmacy, and solar energy converting, makeup, coating, water treatment, tertiary oil recovery, flow improver and flocculation agent etc.
Tert-butyl acrylamide sulfonate (molecular formula C
7h
13nO
4s, hereinafter referred to as AMPS) be a kind of multifunctional water-soluble anionic monomer, due to molecular structure, there is carbon-carbon double bond and to the insensitive sulfonic group of salt, be therefore easy to polymerization.And its homopolymerization and multipolymer have much special character, have broad application prospects, the fields such as oilfield chemistry, water conditioner, chemical fibre, plastics, printing and dyeing, coating, tensio-active agent, static inhibitor, pottery, photograph, washing auxiliary detergent, ion exchange resin, gas separation membrane, electronic industry can be widely used in.
The technique of current most typical production AMPS is with vinyl cyanide, oleum and iso-butylene for raw material, carries out reaction preparation AMPS under relatively mild condition.US Patent No. 3544597 first reported this method preparing amidosulfonic acid compounds, and obtains the higher monomer of purity, but reaction conditions is comparatively harsh.Dong chemical company of Japan (DE2904444A1, DE2904465A1) improves aforesaid method, and proposes the technical scheme obtaining more high purity AMPS.Method described in this patent is that excessive vinyl cyanide is doubled as reaction solvent, in inert gas atmosphere, add oleum under low temperature, under agitation passes into iso-butylene and makes it react.Product A MPS separates out from mixed solution, obtains muddy product.Then add acetic acid to heat up, steam excessive propene nitrile, then add certain water gaging, be warming up to more than 90 DEG C and make it dissolve, then put into cold water and make product crystallization.And clean with acetic acid, more namely obtain high-purity monomer by 60 DEG C of warm air dryings.Existing technique, through improving, after obtaining muddy product, is filtered, and then is carried out vacuum-drying, then uses aqueous acetic acid to carry out recrystallization purification thick product, obtains high purity product.
In existing AMPS production technique, the filtrate that thick product filters, after reclaiming, can produce the by product containing N tert butyl acrylamide.Also contain in mother liquor in addition after recrystallization process filters in a large number based on the by product of the first sulfonic acid of N-tertiary butyl propylene.In the prior art, main employing two kinds of methods process, and one is first use alkaline matter to neutralize, and then send into biochemistry pool and carry out biochemistry, to reach emission request; Second method adopts the method for burning to process.These two kinds of methods not only do not produce economic benefit, and can increase production cost.
Summary of the invention
Prior art is producing in AMPS process the waste residue that can produce in a large number containing by product N-tertiary butyl acryloyl, and an object of the present invention is to provide a kind of method reclaiming N tert butyl acrylamide from the waste residue producing AMPS.
Another object of the present invention is to provide aforesaid method retrieving arrangement used.
Method of the present invention comprises: filter after the mixing of the waste residue of production tert-butyl acrylamide sulfonate, solvent and sorbent material, heating under vacuum filtrate, after solvent evaporation, continue heating remaining solid makes it distil, and reclaims flores and obtains N tert butyl acrylamide.
According to the present invention, the waste residue of described production tert-butyl acrylamide sulfonate is mainly derived from two portions: one is thick product filtrate, and in usual filtrate, solid masses percentage composition is at 3%-15%; Two is the mother liquors after recrystallization filters, and wherein solid masses percentage composition is at 5%-30%.Carry out distillation to described thick product filtrate and mother liquor and can obtain waste residue, in waste residue, the mass percentage of N tert butyl acrylamide is about 4% ~ 95%.Two kinds of waste residues can mix rear employing the solution of the present invention and reclaim, and also can reclaim respectively.
Further illustrate as follows to the mother liquor after thick product filtrate and recrystallization filter: in existing AMPS production technique, first with iso-butylene, sulfuric acid and excessive vinyl cyanide for the thick product of Material synthesis AMPS.Pulpous state solidliquid mixture is obtained, containing the thick product of AMPS, byproduct of reaction containing N tert butyl acrylamide and excessive vinyl cyanide in described mixture after synthesis procedure completes.Filtered and obtained the thick product of AMPS and thick product filtrate, then use acetic acid and water to carry out recrystallization operation as recrystallization solvent to the thick product of AMPS.All containing the byproduct of reaction based on N tert butyl acrylamide in mother liquor after thick product filtrate and recrystallization are filtered.
According to the present invention, the device that removal process uses comprises a heatable separation vessel, for heating the waste residue of production tert-butyl acrylamide sulfonate; The collection container of temperature-adjustable, for collecting the N tert butyl acrylamide distilling and obtain; And vacuum system, for providing low pressure for recovery and product drying process.The pipeline band having heaters of preferred connection separation vessel and collection container, prevents flores from separating out on pipeline.
According to the present invention, sorbent material can use gac or molecular sieve, for the organic impurity adsorbing in waste residue and produce in heat-processed.
According to the present invention, solvent should be selected to be had deliquescent to N tert butyl acrylamide or AMPS, as water, acetone, ethanol, methyl alcohol etc., also two or more solvent can be used.Solvent is used to be to ensure that waste residue to mix with sorbent material and to conduct heat even.Can the methods such as stirring be selected in mixing process, fully contact with waste residue to make solvent.
According to the present invention, adsorbent amount should be more than 2% of slag quality, and the consumption for solvent is not particularly limited.
According to the present invention, filter after solvent, sorbent material and waste residue fully mix, the filtrate of acquisition is joined in separation vessel.Then open heating, make temperature in separation vessel reach 40 ~ 120 DEG C, preferred temperature is 60 ~ 100 DEG C.Lower temperature can make removal process cost a lot of money the time, and higher temperature likely causes waste residue to decompose.
The applicant finds under study for action, and N tert butyl acrylamide at ambient pressure about 128 DEG C fusings also distils simultaneously, and the higher rate of sublimation of temperature is faster, but distillation can cause product colour to change and purity decline at such a temperature.Found by research and analysis, N tert butyl acrylamide at high temperature can decomposite the material containing N-H, O-H, C=O group, and operation can realize distillation at a lower temperature at reduced pressure conditions.Such as, be under the working pressure of 0.005MPa at pressure, 35 DEG C just start distillation, just can find significantly distillation and crystallization at 45 DEG C.Under the working pressure of 0.01MPa, 50gN-N-tert-butyl acrylamide just can realize at 70 DEG C the crystallization recovery that distils in 4h.Therefore decompression operation can reduce the decomposition of N-butylacrylamide in sublimation process, is conducive to preventing waste residue from decomposing and being polymerized.But the too low meeting of separating pressure causes the requirement of vacuum system too high.According to the present invention, separating pressure should control at 1 ~ 50kPa, is preferably 5 ~ 30kPa.
According to the present invention, the temperature of collection container controls below 30 DEG C, and object is that flores is deposited in collection container more.
According to the present invention, the recovery of N tert butyl acrylamide in waste residue can be realized, but due to reclaim flores in there is solvent, need to carry out drying to it.Drying process can be normal operation, if drying temperature can be 50-130 DEG C.Vacuum-drying is better than constant pressure and dry, and preferred drying pressure is less than 30kPa.
In a most preferred embodiment of the present invention, filter after the mixing of the waste residue of production tert-butyl acrylamide sulfonate, solvent and sorbent material, by filtrate heating under vacuum under the condition of 70 ~ 90 DEG C and 10 ~ 15kPa, after solvent evaporation, continue heating remaining solid makes it distil, then flores is reclaimed in the collection container controlled below 30 DEG C in temperature, vacuum-drying, obtains the N tert butyl acrylamide of purity more than 99.5%.
If do not use solvent and sorbent material, reclaim the N tert butyl acrylamide obtained and can present light yellow or light brown, its purity is also lower than 99.5%.Its purity can be brought up to more than 99.5% by method of the present invention, outward appearance is also obviously improved, and can apply having product the field of requirements at the higher level, the product price of this grade can exceed more than 20% than common product price.
Embodiment
Below by embodiment, method of the present invention is described further.
To be compared the main composition and purity of determining product with standard specimen by liquid chromatography (LC).The analysis condition of liquid chromatography is: ZorbaxSAX chromatographic column, and moving phase is 0.1mol/LKH
2pO
4solution, flow velocity is 1.0mL/min, UV-detector.
Embodiment 1
50gAMPS factory mixed sludge is reclaimed according to method of the present invention.In waste residue, the mass percentage of AMPS is 7%, N tert butyl acrylamide mass percentage be 86%, also containing a small amount of other impurity.Waste residue is joined in there-necked flask, then adds 100g water and 5g gac, filter after stirring 5min.Filtrate joined in glass matrass, the water-bath of matrass bottom is heated, and top and underpressure distillation pipeline make electricity consumption silk heat, and opens stirring.Then the temperature in glass matrass is made to remain on 90 DEG C.Temperature in receiving flask is set as 15 DEG C simultaneously.Open vacuum system, make the pressure in retrieving arrangement remain on 10kPa.Removal process continues 2h altogether.Then the material in receiving flask is carried out vacuum-drying.Vacuum drying temperature is 100 DEG C, and drying pressure is 5kPa.Obtain product 39g altogether, main component is N tert butyl acrylamide, is 99.9% by liquid-phase chromatographic analysis purity.
Embodiment 2
Use the recovery method similar to embodiment 1, difference is that matrass and line temperature are set to 70 DEG C, and removal process continues 4h altogether, and vacuum system pressure is 10kPa.The product that obtains in receiving flask after dry materials is total to 37g, and main component is N tert butyl acrylamide, is 99.7% by liquid-phase chromatographic analysis purity.
Embodiment 3
Use the recovery method similar to embodiment 1, difference is that removal process continues 5h altogether, and vacuum system pressure is 15kPa.The product that obtains in receiving flask after dry materials is total to 37.5g, and main component is N tert butyl acrylamide, is 99.6% by liquid-phase chromatographic analysis purity.
Embodiment 4
Use the recovery method similar to embodiment 1, difference is to use acetone as solvent.Removal process continues 2h altogether.In receiving flask, the dried product that obtains is total to 40g, and main component is N tert butyl acrylamide, is 99.7% by liquid-phase chromatographic analysis purity.
Comparative example 1
Use the recovery method similar to embodiment 1, difference is that pressure is normal pressure, and removal process continues 2h altogether.Obtain product 1g in receiving flask after dry materials, most of N tert butyl acrylamide can not be separated from solvent.Be 99.5% by the purity of liquid-phase chromatographic analysis N tert butyl acrylamide.
Comparative example 2
Use the recovery method similar to embodiment 1, difference is not use any sorbent material, and removal process continues 2h.The product that obtains in receiving flask after dry materials is total to 40g, and main component is N tert butyl acrylamide, is 98.3% by liquid-phase chromatographic analysis purity.
Comparative example 3
Use the recovery method similar to embodiment 1, difference is that matrass and line temperature are set to 150 DEG C, and pressure is normal pressure, and removal process continues 3h.The product that obtains in receiving flask after dry materials is total to 37g, and main component is N tert butyl acrylamide, is 97.7% by liquid-phase chromatographic analysis purity.
As can be seen from the result of above-described embodiment and comparative example, normal reclaimer operation cannot be carried out at ambient pressure; After recovered temperature is higher than 60 ~ 100 DEG C of application claims, the purity of the N tert butyl acrylamide of recovery obviously reduces; The purity of the N tert butyl acrylamide not using the comparative example of sorbent material to obtain is lower than employing method of the present invention.Therefore, must carry out under the use of the temperature of application claims, pressure and sorbent material for reclaiming N tert butyl acrylamide in the waste residue from production tert-butyl acrylamide sulfonate.
It should be noted that above-described embodiment only for explaining the present invention, not forming any limitation of the invention.By referring to exemplary embodiments, invention has been described, but to should be understood to word wherein used be descriptive and explanatory vocabulary, instead of limited vocabulary.Can modify the present invention by the scope being defined in the claims in the present invention, and the present invention be revised not deviating from scope and spirit of the present invention.Although the present invention wherein described relates to specific method, material and embodiment, and do not mean that the present invention is limited to particular case disclosed in it, on the contrary, easily extensible of the present invention is to other all methods and applications with identical function.
Claims (10)
1. one kind is reclaimed the method for N tert butyl acrylamide, comprise: filter after the mixing of the waste residue of production tert-butyl acrylamide sulfonate, solvent and sorbent material, heating under vacuum filtrate, after solvent evaporation, continue heating remaining solid makes it distil, and reclaims flores and obtains N tert butyl acrylamide; Described heating under vacuum is carried out under the condition of 40 ~ 120 DEG C and 1 ~ 50kPa.
2. method according to claim 1, is characterized in that, described heating under vacuum is carried out under the condition of 60 ~ 100 DEG C and 5 ~ 30kPa.
3. method according to claim 2, is characterized in that, described heating under vacuum is carried out under the condition of 70 ~ 90 DEG C and 10 ~ 15kPa.
4. method according to claim 1, is characterized in that, the waste residue of described production tert-butyl acrylamide sulfonate derives from tert-butyl acrylamide sulfonate thick product filtrate and the mother liquor after being filtered by thick product recrystallization.
5. method according to claim 1, is characterized in that, described sorbent material is gac and/or molecular sieve.
6. method according to claim 1, is characterized in that, described solvent enables dissolution N tert butyl acrylamide or tert-butyl acrylamide sulfonate.
7. method according to claim 6, is characterized in that, described solvent is selected from least one in water, acetone, ethanol and methyl alcohol.
8. method according to claim 1, is characterized in that, for collecting the vessel temp of flores below 30 DEG C.
9. the method according to any one of claim 1 to 8, is characterized in that, in the flores of recovery, N tert butyl acrylamide purity is more than 99.5%.
10. for the retrieving arrangement of method described in any one of claim 1 to 8, comprise a heatable separation vessel, for heating the waste residue of production tert-butyl acrylamide sulfonate; The collection container of temperature-adjustable, for collecting the N tert butyl acrylamide distilling and obtain; And vacuum system; The pipeline band having heaters of preferred connection separation vessel and collection container.
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| CN201410472828.7A CN105481713A (en) | 2014-09-16 | 2014-09-16 | Method and apparatus for recovering N-t-butyl acrylamide |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112047855A (en) * | 2020-09-19 | 2020-12-08 | 寿光市荣晟新材料有限公司 | N-tert-butyl acrylamide extraction method |
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| CN102952043A (en) * | 2011-08-30 | 2013-03-06 | 中国石油化工股份有限公司 | Synthesis method of tert-butyl acrylamide sulfonate |
| CN103449977A (en) * | 2013-08-19 | 2013-12-18 | 竹山县天新医药化工有限责任公司 | Pyrogallic acid production method |
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| JPH03145455A (en) * | 1989-10-31 | 1991-06-20 | Toagosei Chem Ind Co Ltd | Production of 2-acrylamide-2-methylpropanesulfonic acid |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112047855A (en) * | 2020-09-19 | 2020-12-08 | 寿光市荣晟新材料有限公司 | N-tert-butyl acrylamide extraction method |
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