CN108623474A - It is a kind of to purify N, N, N, the method for N- tetramethyl-1,3-propane diamines using azeotropic distillation - Google Patents
It is a kind of to purify N, N, N, the method for N- tetramethyl-1,3-propane diamines using azeotropic distillation Download PDFInfo
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- CN108623474A CN108623474A CN201710155201.2A CN201710155201A CN108623474A CN 108623474 A CN108623474 A CN 108623474A CN 201710155201 A CN201710155201 A CN 201710155201A CN 108623474 A CN108623474 A CN 108623474A
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- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C209/00—Preparation of compounds containing amino groups bound to a carbon skeleton
- C07C209/82—Purification; Separation; Stabilisation; Use of additives
- C07C209/84—Purification
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Abstract
The invention discloses a kind of method of purification of organic chemical industry's additive, in particular to a kind of N, N, N, the methods of purification of 1,3 propane diamine of N tetramethyls.The present invention is by N, N, N, N tetramethyls 1, entrainer appropriate is added after distillation operation removes light component in the crude reaction of 3 propane diamine, which can form low temperature azeotropic with water, break water and N, N, N, N tetramethyl 1, the azeotropic of 3 propane diamine forms, and can water efficiently be taken out of crude reaction under cryogenic.Entrainer and water dissolving each other at normal temperatures are extremely low so that entrainer and water form two-phase, and water phase can easily be removed as waste water, and entrainer can be used as the Reusability that flows back in organic phase.The present invention is both suitble to intermittently operated, also is adapted for operating continuously.The present invention purifies efficient, entrainer can reuse repeatedly, and operation carry out at low temperature, both improve product quality, can also reduce the energy consumption of operation, be suitble to large-scale industrial production use.
Description
Technical field
The present invention relates to a kind of process for effectively purifying of fine organic additive, specific application is N, N, N, N- tetramethyls
The dehydration of base -1,3- propane diamine is refined.
Technical background
N, N, N, N- tetramethyl-1,3-propane diamine, abbreviation 4-methyl-diaminopropane are a kind of important organic amine additions
Agent is used primarily in the catalyst of polyurethane, the curing agent and catalyst of epoxy resin and the raw material of cationic surfactant,
Etc..4-methyl-diaminopropane is also widely used in dyestuff, medicine intermediate, and catalyst of organic synthesis etc. is a kind of high attached
Value added organic fine chemical products.At normal temperatures, 4-methyl-diaminopropane is that colourless a liquid and water dissolve each other, Er Qierong
It is readily dissolved in methanol, the Conventional solvents such as ethyl alcohol.The atmospheric boiling point of 4-methyl-diaminopropane at 145 DEG C, proportion in 0.782-0.785,
It is a typical tertiary amines organic compound.
There are many manufacturing methods of 4-methyl-diaminopropane, and CN101735068 discloses a kind of use 1,3-PD and two
The method that gas-solid phase reaction of the methylamine under hydro condition prepares 4-methyl-diaminopropane.The organic chemistry that the U.S. in 2002 publishes
Refer to prepare the side of 4-methyl-diaminopropane in reaction (Organic Reactions) using 1,3- propane diamine and formaldehyde reaction
Method.Russ P RUSS2290396 in 2006 is proposed prepares tetramethyl using 1,3- dichloropropanes and dimethylamine reaction
The method of propane diamine.Alternatively, it is also possible to use N, N- dimethyl -1,3- propane diamine does raw material, in high pressure hydrogen atmosphere and catalysis
Under the action of agent and 4-methyl-diaminopropane is obtained by the reaction in formaldehyde.The crude product of 4-methyl-diaminopropane is obtained by the reaction in these, then necessary
The pure 4-methyl-diaminopropane product that can be used as additive could be obtained by refined imurity-removal.
However, there are one common difficult points for the subtractive process for the 4-methyl-diaminopropane that the above method makes.Crude product contains greatly
The water of amount, highest can reach 50% or more, and refined process needs remove water.The water removal of 4-methyl-diaminopropane is very tired
It is difficult.On the one hand, 4-methyl-diaminopropane and water form azeotropic mixture under normal pressure, can not directly be obtained using traditional distillation operation
To pure 4-methyl-diaminopropane；On the other hand, 4-methyl-diaminopropane and water have very strong Hydrogenbond, even if breaking through azeotropic
After composition, the water in 4-methyl-diaminopropane is reduced to can be used as the requirement that additive uses also extremely difficult, needed to be used
There are many number of plates, and even if under very high reflux ratio (5: 1 or 10: 1), moisture can not remove completely.As addition
The 4-methyl-diaminopropane of agent requires water content to be less than 0.5%, preferably shorter than 0.3%, and purity is higher than 98% or more.This is just needed
A kind of efficient water-eliminating method can remove the water of 4-methyl-diaminopropane under conventional factory condition.In existing disclosure
There are no the reports of 4-methyl-diaminopropane efficient water-removing in document and patent report.
Invention content
The present invention proposes a kind of efficient water-eliminating method, and on the one hand can ensure can be with environment-friendly high-efficiency tetramethyl the third two
Water in amine is removed, and so that the water content in product is less than 0.1%, while can ensure the loss of product 4-methyl-diaminopropane most
It is small；On the other hand the energy consumption in separation process can be greatlyd save so that the process has good economy.
The implementation of the present invention is by the following technical programs：
A kind of efficient water-removing method of 4-methyl-diaminopropane, it is characterised in that including following steps：
(1) removing of light component.Herein, light component refers to the atmospheric boiling point substance lower than water.The removing of light component was both
Continuation mode may be used, it can also be by the way of interval.By taking andnon-continuous operation manner as an example, the reaction of 4-methyl-diaminopropane
Crude product pump is driven into rectifying tower reactor, is heated using conduction oil or steam in tower reactor, and the pressure of distillation process is controlled in -0.1-
5MPa, preferably pressure control are in -0.1-1MPa, and more preferable pressure control is in -0.1-0.5Mpa.Then reflux ratio is adjusted, is cut off
React the light component generated
(2) after the light component in reactant is removed, a certain amount of suitable entrainer is added in rectifier column reflux tank,
Rectifying column is squeezed into using reflux.It is preferable to use the solvents that low temperature azeotropic can be formed with water, including aliphatic or aromatic series for entrainer
Hydro carbons, ethers, esters etc. more preferably use the aliphatic or virtue of short chain, it is preferable to use aliphatic or aromatic hydro carbons
The hydro carbons of fragrant race, carbon atoms are in 5-12, the most preferably aliphatic containing 5-8 carbon atom or aromatic hydrocarbon
Class.Azeotropic temperature of the azeotropic temperature that these hydrocarbons and water are formed well below 4-methyl-diaminopropane and water so that entrainment
It is entrained away in the process almost without 4-methyl-diaminopropane product, significantly reduces product loss.This substance includes, but
It is not limited to, benzene, hexamethylene, hexahydrotoluene, normal heptane, n-hexane, toluene, dimethylbenzene, etc.
(3) after the aliphatic containing 5-8 carbon atom or aromatic series alkane are added, water and 4-methyl-diaminopropane have been broken
Azeotropic forms, and efficiently the moisture in 4-methyl-diaminopropane crude product can be removed by distillation operation.The pressure of operation can be with
Selection is in -0.1-5MPa, and preferably pressure control is in -0.1-1MPa, and highly preferred operating pressure is in -0.1-0.2MPa.In this way
Operating pressure water can either be effectively removed, and greatly reduce the temperature of operation, thus greatly reduce the energy of operation
Consumption.It can both be used using entrainer removing moisture and use continuous mode, it can also be by the way of interval.In continuous operation mode
In, 4-methyl-diaminopropane crude product is directly entered the middle part of continuous rectifying tower, moisture and entrainer from overhead extraction.In material split-phase
Afterwards, the organic phase containing entrainer flows back into rectifying column, and water phase directly produces, and no longer flows back into rectifying column.Moisture has taken off
The 4-methyl-diaminopropane removed and height boiling part are then produced from tower reactor.In andnon-continuous operation manner, water by entrainer tower top not
Disconnected extraction, water phase do not flow back, and the organic phase that only entrainer is formed can flow back into rectifying column
(4) fraction cut out from rectifying column top, after condenser, into return tank, because as preferred alkane
Extremely low with the solubility of water, and the difference of the density of alkane and water, phegma can be automatically separated into two-phase, the water phase of bottom and upper
The organic phase in portion.Preferred entrainer must assure that its solubility in water is extremely low, just can ensure that the high efficiency of operation in this way.
Preferred substance includes, but are not limited to, the aliphatic of 5-8 carbon atom or aromatic hydro carbons, such as benzene, hexamethylene, first
Butylcyclohexane, normal heptane, toluene, dimethylbenzene, etc.
(5) because of the addition of entrainer, the azeotropic composition of water and 4-methyl-diaminopropane has been broken so that water is preferentially entrained
Rectifying column is taken in agent out of.Because the solubility of entrainer and water is extremely low, almost immiscible so that entrainer can be with almost 100% quilt
Recycling.The additive amount of entrainer had both been reduced in this way so that process is more environmentally friendly, and entrainer can in return tank
With direct reuse, additional operation equipment is not needed
(5) it is entrained the moisture that agent is taken out of, is plucked out of in return tank, wastewater treatment system can be directly entered as waste water
System.The content of 4-methyl-diaminopropane directly represents the efficiency of entrainer and the quality of waste water in waste water.Highly preferred entrainment
Agent can ensure that the content of the 4-methyl-diaminopropane in waste water is no more than 1% or even 0.1%.This, which both utmostly reduced, has
The loss of component is imitated, and reduces the COD of waste water so that the processing of waste water more simple economy
(6) after the moisture extraction in crude product, remaining material can be conventionally further processed
To final 4-methyl-diaminopropane product.The mode of processing is either can also be interval continuously.Only by taking interval as an example
Explanation.The 4-methyl-diaminopropane crude product for removing moisture and entrainer can be according to conventional distillation operation Methods For Purification.Operation
Pressure can be in -0.1-2MPa, preferably -0.1-1MPa, more preferably -0.1-0MPa.Under preferred pressure, using reasonable
Reflux ratio, purity can be obtained up to 99% or more in tower top, the sterling of 4-methyl-diaminopropane of the moisture less than 0.1%
(7) residue of 4-methyl-diaminopropane crude product rectifying can collect, further to be handled.If residue contains
A certain amount of 4-methyl-diaminopropane product can collect and be added to crude reaction mixing reuse
(8) method of purification proposed by the present invention, efficiency is very high, and pollution is few, and low energy consumption, there is extraordinary economic benefit,
It is very suitable for the production of technical scale metaplasia
Specific implementation method
In conjunction with the method for foregoing description, here is that the present invention will be further described for a specific case study on implementation.This
Example is intended merely to the clearer method for illustrating the invention, but the present invention is not limited only to range and object described in example
Material.
In the tower reactor of the laboratory stuffing rectification column of 1 30mm x 1500mm, 1200 grams of 4-methyl-diaminopropane is added
Crude reaction.Containing moisture 20% or so in crude product, in addition, the purity of 4-methyl-diaminopropane 87%, in addition has some anti-
The impurity for the generation answered, including component that some boiling points are lower than 4-methyl-diaminopropane, referred to herein as light component and some boiling point ratios
The high component of 4-methyl-diaminopropane, referred to herein as heavy constituent
Under normal pressure, kettle material is heated using chuck, kettle material temperature is controlled at 100-120 DEG C.It waits for
After tower top has reflux, jacket temperature is not further added by, and keeps infinite reflux 30 minutes.Then reflux ratio is adjusted 3: 1, and it is light to start extraction
Component.At this point, the temperature of tower top is about fluctuated at 68-72 DEG C, it is more stable.Until the temperature of tower top no longer maintains 68-72
DEG C, when starting to gradually rise, light component produces substantially.The light component collection of extraction carries out in a receiving flask A
It weighs and analyzes
In the state of keeping tower top infinite reflux, hexamethylene is instilled in the tower top of rectifying column.Wait for that the temperature of tower top is stablized
70-75 DEG C or so, start the fraction that tower top is produced with 1: 1 reflux ratio.This temperature is the azeotropic temperature of hexamethylene and water.It evaporates
Divide and is collected into another receiving flask.It is obvious that fraction is divided into two-phase.The organic phase on top is clarified, and the water phase of bottom has
It is a little muddy, show containing a small amount of organic matter.The heating amount and reflux ratio of tower reactor are adjusted, the temperature of tower top can maintain always
70-75 DEG C, also fluctuation is little substantially for the temperature of inner-tower filling material at this time, shows that moisture is constantly plucked out of.Condensed fraction, mainly
It is the mixture of hexamethylene and water, collects for use in a receiving flask B
When the temperature of rectifying column packing layer starts to rise rapidly, extraction finishes the moisture of tower reactor substantially.
At this point, increasing reflux ratio to 3: 1-5: 1, fraction collection to another receiving flask C.This part fraction includes a part of water,
Entrainer hexamethylene, some boiling points in crude reaction are close to the light component of 4-methyl-diaminopropane and partial tetramethyl the third two
Amine.It this part, can the reuse in testing next time as front-end volatiles
After front-end volatiles produce, the heating amount of tower reactor is reduced, bottom temperature is reduced to 40 DEG C or so.Then it uses low
Rectifying, pressure is pressed to be set in 1000Pa or so.Heating amount is adjusted, maintains 30-60 minutes, then adjusts back under total reflux conditions
Ratio is flowed 4: 1-5: 1, and fraction is cut into receiving flask C
The temperature for observing tower top, when tower top temperature maintains 58 DEG C, and it is very stable after, fraction collection to receiving flask D.It returns
Stream is than gradually adjusting to 2: 1-1: 1, collecting fractions.At this point, the temperature of inner-tower filling material layer and the temperature of tower top are basicly stable, and
Only seldom difference is shown to be a kind of very pure material and is producing.It is later analysis shows this is very pure tetramethyl
Propane diamine.Collecting fractions always, until the temperature of packing layer starts to grow steadily.At this moment, reflux ratio is increased to 3: 1-4: 1, together
When in fraction collection to receiving flask E
Until tower reactor material almost without when, stop heating, distillation process terminates.The material of bottom of tower only has at this time
A small amount of height boiling residue
The analysis data preparation of each fraction of rectifying extraction is in table 1
In terms of the analysis data of each fraction of table 1, entrainer can be moisture efficiently from the thick of 4-methyl-diaminopropane
It is removed in product, so as to facilitate economic purification 4-methyl-diaminopropane.Moreover, entrainer can continuous reuse, reduce folder
Dosage with agent.The content of 4-methyl-diaminopropane product in waste water is less than 50ppm, this shows only minimal amount of product useless
It is lost in water.The content of organics of waste water is very low so that the COD of waste water is very low, it is easy to carry out wastewater treatment.
Moisture, using low-pressure distillation, disposably output purity can be higher than 99%, moisture is less than after crude product removing
The product of 0.1% qualified 4-methyl-diaminopropane.The front-end volatiles of rectifying and tails can also collect the original as reuse
Material, this greatly reduces product loss, improves the yield and economy of product.
Table 1：The analysis result of each receiving flask fraction
Claims (4)
1. a kind of purifying N, N, N, the method for N- tetramethyl-1,3-propane diamines, it is characterised in that including following using azeotropic distillation
Several steps：
A. the removing of light component：Continuous rectification mode had both may be used in the removing of light component, can also use the side of batch fractionating
Formula.The pressure of distillation process is controlled in -0.103-5MPa.Then reflux ratio appropriate is taken, the light component that reaction is generated is made
It is produced for the fraction of tower top
B. after the light component in reactant is removed, a certain amount of entrainer is added in rectifier column reflux tank, is beaten using reflux
Enter rectifying column.Entrainer must the solvent of low temperature azeotropic can be formed with water, and the being mutually dissolved property of entrainer and water is less than
5wt%, and it is divided into two-phase in atmospheric conditions, organic phase and water phase.
C. entrainer can form low temperature azeotropic mixture with water, water can efficiently be removed in distillation operation.Distillation operation was both
It can be continuous, can also be interval.The pressure limit of distillation operation is in -0.103-5MPa.Such operating pressure was both
Water can be effectively removed, and greatly reduce the temperature of operation, thus greatly reduces the energy consumption of operation.Water and entrainer
It is divided into two-phase after the low temperature azeotropic mixture of formation is condensed, entrainer may return to rectifying column in organic phase, and water phase does not flow back,
It is constantly produced in tower top, as wastewater treatment.Entrainer can reuse repeatedly.
D. after the moisture extraction in crude product, remaining material can be further processed to obtain according to conventional rectificating method
Final 4-methyl-diaminopropane product.The mode of processing is either can also be interval continuously.The pressure of distillation operation
It can be in -0.103-1MPa.Using rational reflux ratio, purity can be obtained up to 99% or more in tower top, moisture is less than 0.1%
4-methyl-diaminopropane sterling
If E. the residue of 4-methyl-diaminopropane crude product rectifying contains a certain amount of 4-methyl-diaminopropane product, can collect
It is added to crude reaction and mixes reuse；If the content of 4-methyl-diaminopropane is less than 1%, residue treatment can be used as.
2. method of purification according to claim 1, the selection of entrainer includes aliphatic or aromatic hydro carbons, ethers,
Esters etc..Entrainer is either single compound or two or more mixture.Entrainer includes fat
Fat race or aromatic hydro carbons, ethers, the compounds such as esters, it is necessary to can and water formed low temperature azeotropic mixture, and under normal pressure with
The intersolubility of water is less than 5wt%, and stable two-phase can be formed under room temperature.Entrainer can reuse repeatedly in operation.
3. method of purification according to claim 1, the distillation operation pressure in step C can both make in -0.103-1MPa
Intermittently operated can also be used with continuous operation.
4. method of purification according to claim 1, the distillation operation pressure in step D can both make in -0.103-0MPa
Intermittently operated can also be used with continuous operation.
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| CN201710155201.2A CN108623474A (en) | 2017-03-15 | 2017-03-15 | It is a kind of to purify N, N, N, the method for N- tetramethyl-1,3-propane diamines using azeotropic distillation |
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| CN201710155201.2A CN108623474A (en) | 2017-03-15 | 2017-03-15 | It is a kind of to purify N, N, N, the method for N- tetramethyl-1,3-propane diamines using azeotropic distillation |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113429315A (en) * | 2021-06-28 | 2021-09-24 | 河北诚信集团有限公司 | Purification and refining method of alkyl substituted aminoacetonitrile |
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| CN103159629A (en) * | 2011-12-09 | 2013-06-19 | 中国科学院大连化学物理研究所 | Separation method for azeotrope of ethylene diamine and water |
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2017
- 2017-03-15 CN CN201710155201.2A patent/CN108623474A/en active Pending
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| CA1266269A (en) * | 1985-12-17 | 1990-02-27 | Jurgen Weber | Process for the preparation of aliphatic tertiary amines |
| CN101735068A (en) * | 2009-12-07 | 2010-06-16 | 浙江新化化工股份有限公司 | Preparation method of N, N, N, N-tetramethyl-1, 3-propane diamine |
| CN103159629A (en) * | 2011-12-09 | 2013-06-19 | 中国科学院大连化学物理研究所 | Separation method for azeotrope of ethylene diamine and water |
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| CN113429315A (en) * | 2021-06-28 | 2021-09-24 | 河北诚信集团有限公司 | Purification and refining method of alkyl substituted aminoacetonitrile |
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Application publication date: 20181009 |