CN107556241A - The method and apparatus that caprolactam is prepared by trifluoroacetic acid catalysis of pimelinketone oxime Beckmann rearrangement - Google Patents
The method and apparatus that caprolactam is prepared by trifluoroacetic acid catalysis of pimelinketone oxime Beckmann rearrangement Download PDFInfo
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Abstract
The present invention relates to the method and apparatus for preparing caprolactam by trifluoroacetic acid catalysis of pimelinketone oxime Beckmann rearrangement.This method is proton translocation reagent, using trifluoroacetic acid as catalyst using low boiling aprotic material, catalysis of pimelinketone oxime generation Beckmann rearrangement prepares caprolactam at 35~120 DEG C, reaction product is returned to reaction process and recycled by the isolated caprolactam of rectifying and trifluoroacetic acid and low boiling aprotic material, wherein trifluoroacetic acid and low boiling aprotic material.This technological process is short, reaction condition is gentle, energy consumption is low, and producing ammonium sulfate byproduct, not green, and ammonium sulfate device is eliminated compared with traditional handicraft, can effectively reduce caprolactam production cost, caprolactam production is significant.
Description
Technical field
The present invention relates to the method and apparatus that cyclohexanone oxime Beckman (Beckmann) rearrangement prepares caprolactam, specifically
Ground, it is related to the method and apparatus that caprolactam is prepared by trifluoroacetic acid catalysis of pimelinketone oxime Beckmann rearrangement.
Background technology
Caprolactam is a kind of important chemical industry monomer, available for macromolecules such as fiber, engineering plastics, biaxial tension nylons
The synthesis of product, there is very high application value.Caprolactam Industry metaplasia production. art has the acid catalyzed liquid phase rearrangement of oleum
Technique and the vapour phase rearrangement technique of S-1 catalysis, two kinds of preparing process of caprolactam respectively have advantage and disadvantage.
The acid catalyzed liquid phase rearrangement technique of oleum：The use of oleum is catalyst, is urged at a temperature of 110 DEG C or so
Change liquid cyclohexanone oxime and Beckmann rearrangement reactions production rearrangement solution occurs, will with gas ammonia then through ammonium sulfate neutralization crystallizer
Acid neutralizes, and obtains crude amide oil and ammonium sulfate.Go out the higher caprolactam product of purity, and caprolactam by the technique productions
Yield is higher.But still there are some defects in the technique：1. product purification technological process is long, operating procedure is complicated；2. equipment
Early investment is higher, and production cost is also very high；3. 1 ton of caprolactam is often produced in caprolactam production process to be produced
About 1.6 tons of ammonium sulfate byproducts.Accessory substance ammonium sulfate is a kind of acid chemical fertilizer, and added value is low, high energy consumption.
The vapour phase rearrangement technique of S-1 catalysis：Using S-1 catalyst, the catalysis of pimelinketone under 370~380 DEG C of hot conditions
Oxime rearrangement produces caprolactam.The technique replaces oleum using S-1 catalyst in process of production, effectively prevent in oneself
The generation of ammonium sulfate in acid amides production process, asked so as to avoid the marketing problem brought by producing ammonium sulfate byproduct and environmental protection
Topic.But the technique is currently in the technology blockage stage, only SUMITOMO CHEMICAL company is using.The technique is also immature at home,
Fail to find broad application.And the process energy consumption is high, equipment investment is also larger.
From caprolactam production into original, compared with the acid catalyzed liquid phase rearrangement technique of oleum, the gas phase of S-1 catalysis
Reset technique and do not have any cost advantage.Therefore developing a kind of neither producing ammonium sulfate byproduct and can reduces the new technology of production cost
It is imperative.
The content of the invention
The rearrangement solution that the present invention obtains for rearrangement reaction present in existing cyclohexanone oxime production caprolactam technology needs
Neutralize crystallization and obtain 70wt% crude caprolactams oil, in producing process the problem of by-product a large amount of ammonium sulfate, there is provided pass through
The method and apparatus that trifluoroacetic acid catalysis of pimelinketone oxime Beckmann rearrangement prepares caprolactam.
One aspect of the present invention provides prepares caprolactam by trifluoroacetic acid catalysis of pimelinketone oxime Beckmann rearrangement
Method, this method includes：
1) cyclohexanone oxime enters rearrangement reactor with low boiling aprotic material and trifluoroacetic acid, in 35-120 DEG C of weight
Beckmann rearrangement occurs under row's reaction temperature and normal pressure to 0.4MPa.G rearrangement reaction pressure, obtains containing caprolactam
Rearrangement reaction product；
2) the rearrangement reaction product is discharged into rearrangement reaction product reservoir, then with gas-liquid two-phase feeding to rectifying column
In, gas phase enters rectifying column middle and upper part by the flash distillation of rearrangement reaction product reservoir, and liquid phase is entered in the middle part of rectifying column by pump pressurization；
3) in rectifying column, essence is carried out under 130-160 DEG C of column bottom temperature and 0-100KPa.A top operational pressure
Cut is from bottom of towe obtains caprolactam product.
Preferably, in step 1), cyclohexanone oxime is mixed with low boiling aprotic material and trifluoroacetic acid and (preferably passed through
Static mixer mixes) enter rearrangement reactor afterwards.
Preferably, in step 1), cyclohexanone oxime is by cyclohexanone oxime and low boiling aprotic material and trifluoroacetic acid structure
Into rearrangement reaction liquid in concentration be generally 1.4~8mol/L.
Preferably, in step 1), in low boiling aprotic material and trifluoroacetic acid mixture, low boiling aprotic
The concentration of material is 0.1wt%~50wt%, preferably 0.1wt%~10wt%.Above-mentioned low boiling aprotic material can be boiling
Point is less than 100 DEG C, the aprotic material preferably between 30-90 DEG C, is preferably selected from hexamethylene, acetonitrile, acrylonitrile, tetrachloro
Change the one or more of carbon and ether.
In step 1), rearrangement reaction temperature preferably can be 70 DEG C -110 DEG C, more preferably can be 80 DEG C -95 DEG C.Temperature raises
Conversion Selectivity can be improved, but the too high generation that can cause side reaction of temperature, and temperature is too low can reduce conversion ratio.
In step 1), by using external circulating cooling, built-in circulating cooling and pyroreaction trifluoro second at ambient pressure
Acid and low boiling aprotic vaporized species take heat to control rearrangement reaction temperature, are preferably passed through in three kinds of modes using inner coil pipe
Cooling desalted water takes heat.
In step 1), rearrangement reaction pressure preferably can be 0.2-0.3MPa.G.Because trifluoroacetic acid atmospheric boiling point is 72.4
DEG C, need to raise reaction pressure while raising reaction temperature, risen to prevent defervescence.
In step 1), reaction pressure can be entered by exhaust emissions on external world's supplement nitrogen and reactor head gas phase pipeline
Row control.
In step 1), rearrangement reactor can be the reactor that one-pot reaction device or multi-floating bodies operate, preferably by
The reactor of two kettles series connection.
In step 1), it is preferable that tail gas condenser is set at the top of rearrangement reactor, it is preferred to use cooling water and chilled water two
Level cooling, with the trifluoroacetic acid and low boiling aprotic material in higher recovery reaction gas phase.
Therefore, step 1) may further include the trifluoroacetic acid and low boiling aprotic material in recovery reaction gas phase
The step of.The trifluoroacetic acid and low boiling aprotic material of recovery may return to trifluoroacetic acid and low boiling aprotic material
Storage tank, then loop to reactor reuse.Fixed gas enters subsequent treatment workshop section.
Preferably, in step 2), in order to which heat integration utilizes, the gas phase that rearrangement reaction product reservoir flashes off passes through regulation
Valve controls flow to enter rectifying column (alternatively referred to as knockout tower or the own knockout tower of acid) after the 0-50wt% of knockout tower total feed
Middle and upper part, liquid phase enter in the middle part of rectifying column.
Preferably, step 2) and 3) in, rectifying column can be board-like or packed tower, preferred filler tower, filler preferred poly- four
Fluorine filler.
In step 3), the column bottom temperature of rectifying column is preferably 140-155 DEG C, and top operational pressure is preferably 0-40KPa.A,
More preferably 5-20KPa.A.
In step 3), tower reactor reboiler preferably is installed in the bottom of towe of destilling tower, tower reactor reboiler is added by controlling
Low-pressure steam flow controls the column bottom temperature of rectifying column.
In step 3), the High Caprolactam product preferred concentration obtained at rectifying tower bottom is more than 99.5wt%,
Such as 99.5-99.99wt%.
In step 3), it is preferable that by the caprolactam product obtained at rectifying tower bottom with from rearrangement reaction product reservoir
It is fed to the liquid phase in the middle part of destilling tower and carries out heat exchange, in order to which heat integration utilizes.
In step 3), condenser preferably is installed in the tower top of destilling tower, trifluoroacetic acid can be obtained in rectifying column tower top
With low boiling aprotic material liquid phase, wherein being substantially free of caprolactam.Trifluoroacetic acid and low boiling the aprotic thing
Matter liquid phase can be flowed back in rectifying column, can also be returned in trifluoroacetic acid and low boiling aprotic material storage tank, be circulated
Recycle.
In the inventive method, due to the special nature of trifluoroacetic acid, the material of this method device therefor can use enamel,
Hastelloy, inner liner polytetrafluoroethylene, monel metal etc..
Fig. 1 is the process flow diagram according to an embodiment of the invention.As shown in figure 1, from trifluoroacetic acid and
The low boiling aprotic material (for example, acetonitrile) and trifluoroacetic acid of low boiling aprotic material storage tank, and from cyclohexanone
After the cyclohexanone oxime of oxime storage tank is sufficiently mixed in static mixer, enter in rearrangement reactor.Agitator further will
It is sufficiently mixed, and under acid catalysis, carries out Beckmann rearrangement.Belong to exothermic reaction due to resetting, using anti-
Answer and cooling coil is set inside device, by heat removal system controlling reaction temperature, to reach the purpose for removing heat.Reaction pressure passes through outer
Boundary supplements exhaust emissions point journey on nitrogen and reactor head gas phase pipeline and is controlled.Reaction end gas passes through top reaction end gas
After condenser system is condensed, trifluoroacetic acid and low boiling aprotic material return to trifluoroacetic acid and low boiling aprotic thing
Matter storage tank.Fixed gas enters postorder processing workshop section after converging with follow-up rectifying fixed gas.Rearrangement reaction product is from rearrangement reaction
Device overflow is to rearrangement reaction product reservoir.Rearrangement reaction product from rearrangement reaction product reservoir, gas phase enter in rectifying column
Top, liquid phase are sent to the middle part of rectifying column.Rectifying tower bottom by control add tower reactor reboiler low-pressure steam flow come
Kettle temperature is controlled, tower is low to obtain High Caprolactam product, after this caprolactam product carries out heat exchange recovery heat with charging
It is sent into subsequent processing.After rectifying tower top gaseous phase component is condensed by rectifying column tower top condenser system, fixed gas and reaction end gas
Fixed gas be together sent into exhaust gas treatment unit, a liquid part for overhead condensation is sent into rectifying column as backflow, another portion
Divide and be admitted to trifluoroacetic acid and low boiling aprotic material storage tank, recycle.
Another aspect of the present invention provides prepares caprolactam by trifluoroacetic acid acid catalysis cyclohexanone oxime Beckmann rearrangement
Device, including：
Cyclohexanone oxime storage tank, it is used to provide cyclohexanone oxime to rearrangement reactor；
Trifluoroacetic acid and low boiling aprotic material storage tank, it is used to provide low boiling aprotic to rearrangement reactor
Material and trifluoroacetic acid mixture, and receive the low boiling aprotic material and three reclaimed by rearrangement reactor and rectifying column
Fluoroacetic acid is so that it is reused；
Rearrangement reactor, it includes the rearrangement reaction product exit on the feed(raw material)inlet of bottom, the nitrogen inlet at top, top
With the gas vent at top, wherein, the feed(raw material)inlet be used for receive cyclohexanone oxime, low boiling aprotic material and trifluoro second
Acid, the nitrogen inlet are used to supplement nitrogen into rearrangement reactor, and the rearrangement reaction product exit, which is used to discharge, to be reset instead
Product is answered, the gas vent is connected to reaction end gas condenser and is used to discharge gas；
Heat removal system, it is connected to rearrangement reactor, for removing the heat that rearrangement reaction is released in rearrangement reactor；
Reaction end gas condenser, it is respectively connecting to the gas vent of the rearrangement reactor, trifluoroacetic acid and low boiling
Aprotic material storage tank, tail gas is further condensed to recycling, and exported including fixed gas, to discharge fixed gas；
Rearrangement reaction product reservoir, including rearrangement reaction product inlet and outlet, wherein, the rearrangement reaction product inlet
It is described to export for providing rearrangement reaction product to rectifying column for receiving the rearrangement reaction product from rearrangement reactor；
Rectifying column, it includes rearrangement reaction product inlet, the gas vent for being arranged on the rectifier and is arranged on
The caprolactam outlet of the rectifying column bottom, wherein, the rearrangement reaction product inlet is used to receive to be produced from rearrangement reaction
The rearrangement reaction product of thing storage tank, the gas vent are used for the repetition of low boiling aprotic material and trifluoroacetic acid mixture
Utilize, the caprolactam is exported for discharging refined caprolactam product.
In apparatus of the present invention, it is preferable that further comprise static mixer, it is arranged on the rearrangement reactor and trifluoro
Between acetic acid and low boiling aprotic material storage tank, including cyclohexanone oxime entrance, trifluoroacetic acid and low boiling aprotic thing
Matter entrance and outlet, wherein, the cyclohexanone oxime entrance be used for receive the cyclohexanone oxime from cyclohexanone oxime storage tank, described three
Fluoroacetic acid and low boiling aprotic matter inlet are used to receiving from trifluoroacetic acid and low boiling aprotic material storage tank
Low boiling aprotic material and trifluoroacetic acid mixture, the outlet are connected to rearrangement reactor, for by the mixing of mixing
Thing is provided to the rearrangement reactor.
In apparatus of the present invention, it is preferable that further comprise rectifying column tower top condenser, it is arranged on the top of the rectifying column
Portion, be connected with the gas vent for being arranged on the rectifier, for condense the low boiling aprotic material in gas phase and
Trifluoroacetic acid mixture, and be allowed to be back in rectifying column or return to trifluoroacetic acid and low boiling aprotic material storage
Tank, and fixed gas is discharged.
In apparatus of the present invention, it is preferable that tower reactor reboiler is installed in the bottom of towe of destilling tower, for adding tower by controlling
The low-pressure steam flow of kettle reboiler controls the column bottom temperature of rectifying column.
In apparatus of the present invention, it is preferable that further comprise heat exchanger, for by obtained at rectifying tower bottom oneself in acyl
Amine product carries out heat exchange with the liquid phase being fed to from rearrangement reaction product reservoir in the middle part of destilling tower.
In apparatus of the present invention, it is preferable that rectifying column can be board-like or packed tower, preferred filler tower, filler preferably poly- four
Fluorine filler.
In apparatus of the present invention, it is preferable that the heat removal system can be passed through cooling desalted water using internal coil and take heat, force
External cooler is recycled to take heat, vaporize take heat during the course of the reaction using trifluoroacetic acid and low boiling aprotic material, it is excellent
Choosing is passed through cooling desalted water using inner coil pipe and takes heat.
In apparatus of the present invention, because trifluoroacetic acid belongs to strong carboxylic acid, corrosivity is strong, and in terms of equipment selection, this technique is set
Alternative material can use enamel, Hastelloy, inner liner polytetrafluoroethylene, monel metal etc., preferably using liner polytetrafluoroethyl-ne
Alkene, monel metal.
Because water and trifluoroacetic acid mix, a large amount of acid ions can be provided, cause the corrosivity of trifluoroacetic acid, whole reaction
And the system that material contacts in separation process does not allow the presence of water.
In apparatus of the present invention, it is preferable that it is anti-that the rearrangement reactor can be that one-pot reaction device or multi-floating bodies operate
Device is answered, preferably by the reactor of two kettles series connection.
In apparatus of the present invention, it is preferable that reaction end gas condenser can use cooling water and chilled water two-stage to cool down, with more
The efficiently trifluoroacetic acid and low boiling aprotic material in recovery reaction gas phase.
In apparatus of the present invention, it is preferable that rectifying column bottom controls column bottom temperature by reboiler.
Beneficial effect
The present invention has following technique effect：(1) trifluoroacetic acid directly produces caprolactam with cyclohexanone oxime reaction, passes through essence
Isolated High Caprolactam is evaporated, purity can be 99.5-99.99%, and trifluoroacetic acid and low boiling aprotic material can
To recycle；(2) eliminate by neutralizing crystallization, straining wash rice, the ammonium sulfate device that stiff, drying, packaging form, no by-product sulfuric acid
Ammonium, reduced footprint and reduces equipment investment and operating cost；(3) caprolactam concentration that this technique obtains is higher than existing
Technique.
Brief description of the drawings
Fig. 1 is the process flow diagram according to an embodiment of the invention.
Embodiment
With reference to embodiment and accompanying drawing, the invention will be further described.It should be appreciated, however, that these embodiments are only used
It is not meant to limit the scope of the invention in the explanation present invention.
Embodiment 1：
Tested using technological process as shown in Figure 1.
Acetonitrile and trifluoroacetic acid from trifluoroacetic acid and low boiling aprotic material storage tank are dense with 0.3wt% acetonitrile
After degree is by the pressurization of feed pump (not shown), (mixed with the cyclohexanone oxime from cyclohexanone oxime storage tank with acetonitrile and trifluoroacetic acid
Concentration is 1.9mol/L afterwards) be sufficiently mixed in static mixer after, enter the annular distribution pipe of rearrangement reactor bottom, warp
Agitator is further sufficiently mixed, and under acid catalysis, carries out Beckmann rearrangement；Due to rearrangement reaction category
In exothermic reaction, cooling coil is set using inside reactor, it is cold to supply inner coil pipe by the cooling desalination pump of heat removal system
But water, by cooling water amount controlling reaction temperature at 80 DEG C, to reach the purpose for removing heat；Reaction pressure supplements nitrogen by the external world
Exhaust emissions Staged cotrol passes through top reaction end gas in 0.15MPa.G, reaction end gas on gas and reactor head gas phase pipeline
After condenser (or being tail gas condensing system) is condensed, acetonitrile and trifluoroacetic acid liquid returns to trifluoroacetic acid and low boiling is non-
Protic material storage tank；Fixed gas enters postorder processing workshop section after converging with follow-up rectifying fixed gas；Rearrangement reaction product is certainly
Reactor overflow is to rearrangement reaction product reservoir, rearrangement reaction conversion ratio 99.5%, selectivity 98.3%.
Caprolactam, acetonitrile and trifluoroacetic acid mixture from rearrangement reaction product reservoir, gas phase enter in rectifying column
Top, after liquid phase is pressurizeed by piece-rate system feed pump (not shown), the middle part of rectifying column is fed to, bottom of towe is added by control
Enter tower reactor reboiler low-pressure steam flow to control kettle temperature to maintain 145 DEG C, bottom of towe obtains 99.8wt% highly concentrated interior acyl of redeeming oneself
Amine, this material carry out being sent into follow-up refined dress after heat is reclaimed in heat exchange with the liquid phase feeding fed by piece-rate system feed pump
Put.
Rectifying tower pressure on top surface is controlled by jet pump passes through rectifying column tower top condenser in 4KPa.A, top gas phase component
After (or being rectifying column tower top condenser system) condensation, liquid is entered in rectifier column reflux tank (not shown), fixed gas with it is anti-
Tail gas fixed gas is answered together to be sent into exhaust gas treatment unit；After the liquid of overhead condensation is pressurizeed by rectifier column reflux pump, one work
Sent back to for backflow in rectifying column；Another stock is admitted to trifluoroacetic acid and low boiling aprotic material storage tank is recycled to reaction and thought highly of
It is multiple to utilize.
Embodiment 2：
Tested using technological process as shown in Figure 1.
Acetonitrile and trifluoroacetic acid from trifluoroacetic acid and low boiling aprotic material storage tank are with 5wt% acetonitrile concentration
After being pressurizeed by feed pump (not shown), with the cyclohexanone oxime from cyclohexanone oxime storage tank (after being mixed with acetonitrile and trifluoroacetic acid
Concentration is 1.9mol/L) be sufficiently mixed in static mixer after, the annular distribution pipe of rearrangement reactor bottom is entered, through stirring
Mix device to be further sufficiently mixed, and under acid catalysis, carry out Beckmann rearrangement；Because rearrangement reaction belongs to
Exothermic reaction, cooling coil is set using inside reactor, supplying inner coil pipe by the cooling desalination pump of heat removal system cools down
Water, by cooling water amount controlling reaction temperature at 90 DEG C, to reach the purpose for removing heat；Reaction pressure supplements nitrogen by the external world
And exhaust emissions Staged cotrol is condensed in 0.3MPa.G, reaction end gas by top reaction end gas on reactor head gas phase pipeline
After device (or being tail gas condensing system) is condensed, acetonitrile and trifluoroacetic acid liquid returns to trifluoroacetic acid and low boiling is non-proton
Property material storage tank；Fixed gas and the rectifying fixed gas of subsequent handling enter postorder processing workshop section after converging；Rearrangement reaction product is certainly
Reactor overflow is to rearrangement reaction product reservoir, rearrangement reaction conversion ratio 99.5%, selectivity 99.3%.
The mixture of caprolactam, trifluoroacetic acid and acetonitrile from rearrangement reaction product reservoir, gas phase enter rectifying column
Middle and upper part, after liquid phase is pressurizeed by piece-rate system feed pump (not shown), the middle part of rectifying column is fed to, bottom of towe passes through control
Tower reactor reboiler low-pressure steam flow is added to control kettle temperature to maintain 150 DEG C, bottom of towe obtain 99.9wt% it is highly concentrated redeem oneself in
Acid amides, this material and the liquid phase feeding fed by piece-rate system feed pump are sent into next work after carrying out heat exchange recovery heat
Sequence.
Rectifying tower pressure on top surface is controlled by jet pump and condensed in 10KPa.A, top gas phase component by rectifying column tower top
Device (or being rectifying column tower top condenser system) condensation after, liquid is entered in rectifier column reflux tank (not shown), fixed gas with
Reaction end gas fixed gas is together sent into exhaust gas treatment unit；After the liquid of overhead condensation is pressurizeed by rectifier column reflux pump, one
As back up through sending back in rectifying column；Another stock is admitted to trifluoroacetic acid and low boiling aprotic material storage tank is recycled to instead
Device is answered to reuse.
Embodiment 3：
Tested using technological process as shown in Figure 1.
Acetonitrile and trifluoroacetic acid from trifluoroacetic acid and low boiling aprotic material storage tank are dense with 0.1wt% acetonitrile
After degree is by the pressurization of feed pump (not shown), (mixed with the cyclohexanone oxime from cyclohexanone oxime storage tank with trifluoroacetic acid and acetonitrile
Concentration is 3mol/L afterwards) be sufficiently mixed in static mixer after, the annular distribution pipe of rearrangement reactor bottom is entered, through stirring
Mix device to be further sufficiently mixed, and under acid catalysis, carry out Beckmann rearrangement；Because rearrangement reaction belongs to
Exothermic reaction, cooling coil is set using inside reactor, supplying inner coil pipe by the cooling desalination pump of heat removal system cools down
Water, by cooling water amount controlling reaction temperature at 80 DEG C, to reach the purpose for removing heat；Reaction pressure supplements nitrogen by the external world
And exhaust emissions Staged cotrol is condensed in 0.2MPa.G, reaction end gas by top reaction end gas on reactor head gas phase pipeline
After device (or being tail gas condensing system) is condensed, trifluoroacetic acid and acetonitrile liquid returns to trifluoroacetic acid and low boiling is non-proton
Property material storage tank；Fixed gas and the rectifying fixed gas of subsequent handling enter postorder processing workshop section after converging；Rearrangement reaction product is certainly
Reactor overflow is to rearrangement reaction product reservoir, rearrangement reaction conversion ratio 99.9%, selectivity 94.5%.
The mixture of caprolactam, trifluoroacetic acid and acetonitrile from rearrangement reaction product reservoir, gas phase enter rectifying column
Middle and upper part, after liquid phase is pressurizeed by piece-rate system feed pump (not shown), the middle part of rectifying column is fed to, bottom of towe passes through control
Tower reactor reboiler low-pressure steam flow is added to control kettle temperature to maintain 150 DEG C, bottom of towe obtain 99.9wt% it is highly concentrated redeem oneself in
Acid amides, this material and the liquid phase feeding fed by piece-rate system feed pump are sent into next work after carrying out heat exchange recovery heat
Sequence.
Rectifying tower top pressure is controlled by jet pump passes through rectifying column tower top condenser in 10KPa.A, top gas phase component
After (or being rectifying column tower top condenser system) condensation, liquid is entered in rectifier column reflux tank (not shown), fixed gas with it is anti-
Tail gas fixed gas is answered together to be sent into exhaust gas treatment unit；After the liquid of overhead condensation is pressurizeed by rectifier column reflux pump, one work
For back up through sending back in rectifying column；Another stock is admitted to trifluoroacetic acid and low boiling aprotic material storage tank is recycled to reaction
Device reuses.
Claims (10)
1. the method for preparing caprolactam by trifluoroacetic acid catalysis of pimelinketone oxime Beckmann rearrangement, this method include：
1) cyclohexanone oxime enters rearrangement reactor with low boiling aprotic material and trifluoroacetic acid, anti-in 35-120 DEG C of rearrangement
Answer and Beckmann rearrangement occurs under temperature and normal pressure to 0.4MPa.G rearrangement reaction pressure, obtain the weight containing caprolactam
Arrange reaction product；
2) the rearrangement reaction product is discharged into rearrangement reaction product reservoir, then with gas-liquid two-phase feeding into rectifying column, gas
Communicated the flash distillation of rearrangement reaction product storage tank and enter rectifying column middle and upper part, liquid phase is entered in the middle part of rectifying column by pump pressurization；
3) in rectifying column, rectifying point is carried out under 130-160 DEG C of column bottom temperature and 0-100KPa.A top operational pressure
From bottom of towe obtains caprolactam product.
2. the method for claim 1, wherein
In step 1), rearrangement reactor is entered after cyclohexanone oxime is mixed with low boiling aprotic material and trifluoroacetic acid；With/
Or
In step 1), cyclohexanone oxime is in the rearrangement reaction being made up of cyclohexanone oxime and low boiling aprotic material and trifluoroacetic acid
Concentration in liquid is generally 1.4~8mol/L；And/or
In step 1), in low boiling aprotic material and trifluoroacetic acid mixture, the concentration of low boiling aprotic material
For 0.1wt%~50wt%；And/or
In step 1), rearrangement reaction temperature is 70 DEG C -110 DEG C, preferably 80 DEG C -95 DEG C；And/or
In step 1), rearrangement reaction pressure is 0.2-0.3MPa.G.
3. the method for claim 1, wherein the low boiling aprotic material is that boiling point is less than 100 DEG C, preferably exist
Aprotic material between 30-90 DEG C, more preferably one kind selected from hexamethylene, acetonitrile, acrylonitrile, carbon tetrachloride and ether
It is or a variety of.
4. the method for claim 1, wherein
In step 1), by using external circulating cooling, built-in circulating cooling and at ambient pressure pyroreaction trifluoroacetic acid and
Low boiling aprotic vaporized species take heat to control rearrangement reaction temperature, it is preferred to use inner coil pipe is passed through cooling desalted water and taken
Heat, and/or
In step 1), reaction pressure is controlled by exhaust emissions on external world's supplement nitrogen and reactor head gas phase pipeline；
And/or
In step 1), rearrangement reactor is the reactor that one-pot reaction device or multi-floating bodies operate, and is connected preferably by two kettles
Reactor；And/or
In step 1), tail gas condenser is set at the top of rearrangement reactor, it is preferred to use cooling water and the cooling of chilled water two-stage, with more
Trifluoroacetic acid and low boiling aprotic material in high recovery reaction gas phase.
5. the method for claim 1, wherein step 1) further comprises the trifluoroacetic acid and low in recovery reaction gas phase
The step of boiling point aprotic material.
6. the method for claim 1, wherein
In step 2), the gas phase that rearrangement reaction product reservoir flashes off is by governor valve control flow in knockout tower total feed
Enter rectifying column middle and upper part after 0-50wt%, liquid phase enters in the middle part of rectifying column；And/or
Step 2) and 3) in, rectifying column is board-like or packed tower, preferred filler tower, the preferred polytetrafluoro filler of filler.
7. the method for claim 1, wherein
In step 3), the column bottom temperature of rectifying column is 140-155 DEG C, and top operational pressure is 0-40KPa.A, preferably 5-
20KPa.A；And/or
In step 3), tower reactor reboiler is installed in the bottom of towe of destilling tower, the low-pressure steam of tower reactor reboiler is added by controlling
Flow controls the column bottom temperature of rectifying column；And/or
In step 3), by the caprolactam product obtained at rectifying tower bottom with being fed to destilling tower from rearrangement reaction product reservoir
The liquid phase at middle part carries out heat exchange, in order to which heat integration utilizes；And/or
In step 3), condenser is installed in the tower top of destilling tower, to obtain trifluoroacetic acid in rectifying column tower top and low boiling is non-
Protic material liquid phase.
8. the device of caprolactam is prepared by trifluoroacetic acid catalysis of pimelinketone oxime Beckmann rearrangement, including：
Cyclohexanone oxime storage tank, it is used to provide cyclohexanone oxime to rearrangement reactor；
Trifluoroacetic acid and low boiling aprotic material storage tank, it is used to provide low boiling aprotic material to rearrangement reactor
With trifluoroacetic acid mixture, and the low boiling aprotic material reclaimed by rearrangement reactor and rectifying column and trifluoro second are received
Acid is so that it is reused；
Rearrangement reactor, it includes the feed(raw material)inlet of bottom, the nitrogen inlet at top, the rearrangement reaction product exit on top and top
The gas vent in portion, wherein, the feed(raw material)inlet is used to receive cyclohexanone oxime, low boiling aprotic material and trifluoroacetic acid,
The nitrogen inlet is used to supplement nitrogen into rearrangement reactor, and the rearrangement reaction product exit is used to discharge rearrangement reaction production
Thing, the gas vent are connected to reaction end gas condenser and are used to discharge gas；
Heat removal system, it is connected to rearrangement reactor, for removing the heat that rearrangement reaction is released in rearrangement reactor；
Reaction end gas condenser, it is respectively connecting to the gas vent of the rearrangement reactor, trifluoroacetic acid and the non-matter of low boiling
Sub- property material storage tank, tail gas is further condensed to recycling, and exported including fixed gas, to discharge fixed gas；
Rearrangement reaction product reservoir, including rearrangement reaction product inlet and outlet, wherein, the rearrangement reaction product inlet is used for
The rearrangement reaction product from rearrangement reactor is received, it is described to export for providing rearrangement reaction product to rectifying column；
Rectifying column, it includes rearrangement reaction product inlet, the gas vent for being arranged on the rectifier and is arranged on described
The caprolactam outlet of rectifying column bottom, wherein, the rearrangement reaction product inlet is used to receive to be stored up from rearrangement reaction product
The rearrangement reaction product of tank, the gas vent are used for the repetition profit of low boiling aprotic material and trifluoroacetic acid mixture
With the caprolactam is exported for discharging refined caprolactam product.
9. device as claimed in claim 8, wherein,
The device further comprises static mixer, and it is arranged on the rearrangement reactor and trifluoroacetic acid and low boiling are non-proton
Property material storage tank between, including cyclohexanone oxime entrance, trifluoroacetic acid and low boiling aprotic matter inlet and outlet, wherein,
The cyclohexanone oxime entrance is used to receive the cyclohexanone oxime from cyclohexanone oxime storage tank, and the trifluoroacetic acid and low boiling are non-proton
Property matter inlet be used to receiving low boiling aprotic material from trifluoroacetic acid and low boiling aprotic material storage tank and
Trifluoroacetic acid mixture, the outlet are connected to rearrangement reactor, for the mixture of mixing to be provided to the rearrangement reaction
Device；And/or
The device further comprises rectifying column tower top condenser, and it is arranged on the top of the rectifying column, with being arranged on the essence
The gas vent for evaporating tower top is connected, for condensing low boiling aprotic material and trifluoroacetic acid mixture in gas phase, and
It is allowed to be back in rectifying column or returns to trifluoroacetic acid and low boiling aprotic material storage tank, and fixed gas is discharged；
And/or
Tower reactor reboiler is installed in the bottom of towe of destilling tower, for by control add tower reactor reboiler low-pressure steam flow come
Control the column bottom temperature of rectifying column；And/or
The device further comprises heat exchanger, for the High Caprolactam product that will be obtained at rectifying tower bottom and from again
The liquid phase that row's reaction product storage tank is fed in the middle part of destilling tower carries out heat exchange.
10. device as claimed in claim 8, wherein,
The rectifying column is board-like or packed tower, preferred filler tower, the preferred polytetrafluoro filler of filler；And/or
The heat removal system can be passed through cooling desalted water using internal coil and take heat, forced circulation to external cooler to take heat, adopt
Vaporized taken heat during the course of the reaction with trifluoroacetic acid and low boiling aprotic material, it is preferred to use inner coil pipe is passed through cooling desalination
Water takes heat；And/or
The rearrangement reactor is the reactor that one-pot reaction device or multi-floating bodies operate, preferably by the reaction of two kettles series connection
Device；And/or
Reaction end gas condenser is cooled down using cooling water and chilled water two-stage, more efficiently to reclaim the trifluoro second in reaction gas phase
Acid and low boiling aprotic material；And/or
Rectifying column bottom controls column bottom temperature by reboiler.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114478385A (en) * | 2022-02-24 | 2022-05-13 | 江苏扬农化工集团有限公司 | Method for preparing caprolactam by reactive distillation |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS4835271B1 (en) * | 1970-12-26 | 1973-10-26 | ||
| CN102895996A (en) * | 2012-10-09 | 2013-01-30 | 清华大学 | Catalytic system for Beckmann rearrangement of oxime |
| CN104981454A (en) * | 2012-12-19 | 2015-10-14 | 巴斯夫欧洲公司 | Method for the production of purified caprolactam from the beckmann rearrangement of cyclohexanone oxime |
| CN105017117A (en) * | 2015-07-08 | 2015-11-04 | 南京工业大学 | Method for pilot-plant-scale production of caprolactam in micro-reaction device |
| CN205575970U (en) * | 2016-03-28 | 2016-09-14 | 湖南百利工程科技股份有限公司 | Caprolactam refining plant |
-
2017
- 2017-01-19 CN CN201710043734.1A patent/CN107556241A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS4835271B1 (en) * | 1970-12-26 | 1973-10-26 | ||
| CN102895996A (en) * | 2012-10-09 | 2013-01-30 | 清华大学 | Catalytic system for Beckmann rearrangement of oxime |
| CN104981454A (en) * | 2012-12-19 | 2015-10-14 | 巴斯夫欧洲公司 | Method for the production of purified caprolactam from the beckmann rearrangement of cyclohexanone oxime |
| CN105017117A (en) * | 2015-07-08 | 2015-11-04 | 南京工业大学 | Method for pilot-plant-scale production of caprolactam in micro-reaction device |
| CN205575970U (en) * | 2016-03-28 | 2016-09-14 | 湖南百利工程科技股份有限公司 | Caprolactam refining plant |
Non-Patent Citations (2)
| Title |
|---|
| L. RONCHIN ET AL.: "On the mechanism of the organocatalyzed Beckmann rearrangement of cyclohexanone oxime by trifluoroacetic acid in aprotic solvent", 《JOURNAL OF MOLECULAR CATALYSIS A: CHEMICAL》 * |
| 张一等: "《化工控制技术》", 31 May 2014, 北京：北京航空航天大学出版社 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114478385A (en) * | 2022-02-24 | 2022-05-13 | 江苏扬农化工集团有限公司 | Method for preparing caprolactam by reactive distillation |
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