CN104876782B - The method of the organic solvent of a kind of processing cycle and the preparation method of caprolactam - Google Patents
The method of the organic solvent of a kind of processing cycle and the preparation method of caprolactam Download PDFInfo
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- CN104876782B CN104876782B CN201410069288.8A CN201410069288A CN104876782B CN 104876782 B CN104876782 B CN 104876782B CN 201410069288 A CN201410069288 A CN 201410069288A CN 104876782 B CN104876782 B CN 104876782B
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- organic solvent
- cyclohexanone
- oxime
- caprolactam
- alkaline matter
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Abstract
The method that the invention discloses the organic solvent of a kind of processing cycle, it is characterized in that, manufacturing in caprolactam process the amidatioon liquid obtained and make the organic solution of the cyclohexanone-oxime obtained in caprolactam process by coming from toluene method with benzene legal system and contact and carry out the organic solvent of Beckmann rearrangement reaction isolated and contact with alkaline matter, alkaline matter addition makes the octahydro azophenlyene content in the product of the Beckmann rearrangement reaction of the organic solvent participation of recycling be less than 15 μ g/g.The method can effectively prevent cyclohexanone-oxime polycondensation from impact and the condensation polymer of caprolactam yield are blocked in material conveying process pipeline.
Description
Technical field
The present invention relates to process method and the system of caprolactam of the organic solvent circulated in the preparation process of caprolactam
Preparation Method, the method that the present invention relates to furtherly process the organic solvent through Beckmann rearrangement process solvent vaporization cycle
And the method that caprolactam is prepared in Beckmann rearrangement accordingly.
Background technology
Caprolactam is a kind of important Organic Chemicals, mainly for the production of nylon-6 fiber and nylon 6 engineering plastic
Material.Currently it is applied to industrial caprolactam preparation method mainly have: Ketohexamethylene-azanol production technology or amidoxime chemical industry
Skill (being called for short " benzene method "), hexamethylene photonitrosation technique and SNIA toluene technique.Wherein, Ketohexamethylene-azanol production technology is with benzene
For raw material, through producing cyclohexane by benzene hydrogenation, cyclohexane oxidation preparing cyclohexanone, Ketohexamethylene oximate or oximes preparing cyclohexanone oxime, hexamethylene
Ketoxime through Beckmannn reset, the most neutralized, extract and be refining to obtain caprolactam；SNIA toluene technique, is former with toluene
Material, oxidized produces benzoic acid, Hydrogenation hexahydrobenzoic acid, carries out nitrosation with nitrosylsulfuric acid under the effect of oleum
React, again through hydrolyzing, neutralizing and be refining to obtain caprolactam.SNIA toluene method is compared with benzene method, and advantage is process conditions temperature
With, early stage process costs is relatively low, and the production cost of hexahydrobenzoic acid is only the 2/3 of cyclohexanone-oxime；But shortcoming is long flow path, secondary
Produce ammonium sulfate and be up to about 4.0 tons of ammonium sulfate/ton caprolactam.Additionally, the substantial amounts of ammonium sulfate of by-product, also limit existing apparatus raw
The expansion of production capacity power or the construction of new equipment.CN1130181A discloses a kind of in the case of not increasing ammonium sulfate by-product amount,
Improve SNIA toluene technique caprolactam production ability method, i.e. aliphatic series and/or cycloaliphatic carboxylic acid in the presence of, by ketoxime with
Oleum carries out Beckmannn and resets generation amide.The mixture of carboxylic acids that it is given contain hexahydrobenzoic acid, caprolactam,
Sulfur trioxide and sulphuric acid；Cyclohexanone-oxime is added directly in mixture and carries out rearrangement reaction.
For the deficiency of existing SNIA toluene Technology, CN103012262A discloses a kind of side producing caprolactam
Method, the cyclohexanone-oxime that its process is the amidatioon liquid that obtains of toluene method and benzene method obtains carries out resetting anti-in rearrangement reactor
Should, product is neutralized, crystallize, extract, subtractive process makes caprolactam, this process employs three oxidations in amide liquid
Sulfur and sulphuric acid are that catalyst carries out rearrangement reaction.
Summary of the invention
Owing to cyclohexanone-oxime dissolved solution degree is low, the reaction heat of Beckmannn rearrangement reaction is the biggest, it is impossible to adopt completely
With fresh organic solvent, therefore, the organic solvent of evaporation need to be circulated and re-use.The organic solvent that circulation re-uses have miscellaneous
Matter, promotes cyclohexanone-oxime condensation polymer to be formed, and not only affects product quality, and can blocking pipeline.Inventor is at great many of experiments
On the basis of find, with toluene and benzene as initial feed, i.e. manufacture the amidatioon liquid obtained in caprolactam process with toluene method
The organic solution making the cyclohexanone-oxime obtained in caprolactam process with benzene legal system contacts the collection carrying out Beckmann rearrangement reaction
During one-tenth technology prepares caprolactam, in the organic solvent of circulation, add a small amount of alkaline matter, can effectively prevent hexamethylene
Ketoxime polycondensation is on the impact of cyclohexanone-oxime yield and reduces condensation polymer in material conveying process to line clogging, and finally carries
High caprolactam product quality.Based on this, form the present invention.
An object of the present invention is for the deficiencies in the prior art, it is provided that the side of the organic solvent of a kind of processing cycle
Method, the two of purpose are to provide the preparation method of a kind of caprolactam, and the method can preferably solve toluene and benzene for the most former
During material cyclohexanone-oxime generation polycondensation and and condensation polymer at material conveying process to line clogging problem, and finally improve acyl in oneself
Amine product quality.
The method of the organic solvent of the processing cycle that the present invention provides, it is characterised in that toluene method will be come from and manufacture oneself
The amidatioon liquid obtained during lactams and benzene legal system are made the organic solution of the cyclohexanone-oxime obtained in caprolactam process and are connect
The tactile organic solvent carrying out Beckmann rearrangement reaction isolated contacts with alkaline matter, and alkaline matter addition makes to follow
Octahydro azophenlyene content in the product of the Beckmann rearrangement reaction that the organic solvent that ring uses participates in is less than 15 μ g/g.
The preparation method of a kind of caprolactam that the present invention also provides for, is to manufacture toluene method in caprolactam process to obtain
Amidatioon liquid make the organic solution of the cyclohexanone-oxime obtained in caprolactam process with benzene legal system and contact and carry out Beckmann weight
Row's reaction isolated product and organic solvent, wherein, described product is again through including neutralizing, crystallize, extracting
Obtain caprolactam with subtractive process, and described organic solvent is through recycling, it is characterised in that described cyclohexanone-oxime
In organic solution, organic solvent is at least partially from the organic solvent recycled and the organic solvent of described recycling
First contact with a kind of alkaline matter before contacting preparation with cyclohexanone-oxime and obtaining the organic solution of cyclohexanone-oxime so that make through circulating
The product of Beckmann rearrangement reaction that participates in of organic solvent in octahydro azophenlyene content less than 15 μ g/g.
The method of the organic solvent of the processing cycle that the present invention provides and the preparation method of caprolactam, can the most anti-stop ring
Hexanone oxime polycondensation, reduces condensation polymer in the material conveying process degree to line clogging.
Accompanying drawing explanation
Accompanying drawing is one embodiment of the invention.
Detailed description of the invention
The method of the organic solvent of the processing cycle that the present invention provides, it is characterised in that toluene method will be come from and manufacture oneself
The amidatioon liquid obtained during lactams and benzene legal system are made the organic solution of the cyclohexanone-oxime obtained in caprolactam process and are connect
The tactile organic solvent carrying out Beckmann rearrangement reaction isolated contacts with alkaline matter, and alkaline matter addition makes to follow
Octahydro azophenlyene content in the product of the Beckmann rearrangement reaction that the organic solvent that ring uses participates in is less than 15 μ g/g.
In order to make cyclohexanone-oxime be dispersed in very well in amidation process liquid, use the charging side of the organic solution of cyclohexanone-oxime
Method.In rearrangement reaction, the effect of organic solvent has two aspects, and one is that cyclohexanone-oxime charging can realize its molecular scale
Mixing, two is to remove reaction heat by organic solvent evaporation, and reaction temperature can be kept stable.The method that the present invention provides, described
One or more in benzene, toluene, hexamethylene and hexane of organic solvent, wherein preferably organic solvent is hexane.By
Under cyclohexanone-oxime room temperature, dissolubility is limited in organic solvent, and the reaction heat of Beckmannn rearrangement reaction is big again, solvent load
Very big, therefore can not use fresh organic solvent completely, the solvent of evaporation need to be circulated and re-use, come from recycling
Organic solvent generally account for total organic solvent amount no less than 95%, the normal loss of deduction, it is preferable that be typically very to follow
Ring uses.
Described alkaline matter is inorganic base or its aqueous solution, and inorganic base is selected from sodium hydroxide, potassium hydroxide, hydroxide
One or more in calcium, sodium carbonate, calcium carbonate and ammonia, the most preferably sodium hydroxide or ammonia, described alkaline matter,
Its concentration of aqueous solution is close to saturated concentration or saturated concentration, wherein preferred saturated concentration.The method that the present invention provides, passes through
The critical impurities octahydro in rearrangement reaction product obtained by the integrated process that the organic solvent re-using circulation participates in
The control less than 15 μ g/g, preferably more than 10 μ g/g of the content's index of azophenlyene, the addition of the alkaline matter described in setting.
The Adding Way of described alkaline matter is to join in circulation organic solvent by Hi-mixer by alkali liquor, circulates organic molten
Agent is continuous phase, and alkali liquor is dispersion phase, reaches biphase quick mixing.Described organic solvent is in the step contacted with alkaline matter
In Zhou, Contact Temperature is 5-80 DEG C, preferably 25-60 DEG C.
The preparation method of the caprolactam that the present invention provides on the basis of the method for the organic solvent of processing cycle, is by first
Benzene legal system makes the amidatioon liquid obtained in caprolactam process and benzene legal system makes the cyclohexanone-oxime that obtains in caprolactam process
Organic solution contact carries out Beckmann rearrangement reaction isolated product and organic solvent, wherein, described reaction
Product is again through including neutralizing, crystallize, extract and subtractive process obtaining caprolactam, and described organic solvent is through recycling,
It is characterized in that, in the organic solution of described cyclohexanone-oxime, organic solvent is at least partially from organic molten in recycle
The organic solvent of agent and described recycling before contacting preparation with cyclohexanone-oxime and obtaining the organic solution of cyclohexanone-oxime first with
A kind of alkaline matter contact so that the octahydro in the product of the Beckmann rearrangement reaction that the organic solvent through recycling participates in
Azophenlyene content is less than 15 μ g/g.
The organic solvent of circulation is contacted by the present invention with alkaline matter, is participated in by the organic solvent controlled through recycling
Beckmann rearrangement reaction product in octahydro azophenlyene content less than 15 these parameters of μ g/g, with having of circulation up to standard
Machine solvent participates in the organic solution of preparation cyclohexanone-oxime, can avoid cyclohexanone-oxime generation polycondensation, reach above-mentioned reduction condensation polymer and exist
The material conveying process purpose to line clogging degree.
In the method that the present invention provides, the organic solvent of described recycling obtains ring contacting preparation with cyclohexanone-oxime
The temperature of the organic solution of hexanone oxime is 0-80 DEG C, and cyclohexanone-oxime feeding temperature is more than its fusing point, cyclohexanone-oxime and organic solvent
Addition is determined depending on the concentration preparing cyclohexanone-oxime organic solution, prepares and carries out in having the container of stirring and mixed function.
In the organic solution of described cyclohexanone-oxime, the organic solvent coming from recycling accounts for the 95～100% of total organic solvent.
Accompanying drawing illustrates one embodiment of the invention.
In the accompanying drawings, cyclohexanone-oxime (4) and the circulation organic solvent (7) after contacting with alkaline matter are in stirred tank (1)
Preparation cyclohexanone-oxime organic solution (6), cyclohexanone-oxime organic solution (6) occurs in reactor (2) with amidation process liquid (5)
Beckmann rearrangement reaction obtains rearrangement reaction liquid (10), and the organic solvent (8) of heat release evaporation in reactor (3) with alkalescence
Material (9) contact obtains circulation organic solvent (7), described rearrangement reaction liquid (10) again through hydrolyzing, neutralize, crystallize, extract and
Subtractive process obtains caprolactam product.
Below by embodiment, the invention will be further described, but content not thereby limiting the invention.
Comparative example 1
The result that this comparative example explanation organic solvent is the most treated, recycle.
The hexane preparation cyclohexanone-oxime hexane solution of circulation: preparation temperature about 60 DEG C, preparation is to enter in the still of band stirring
OK.Cyclohexanone-oxime feeding temperature 92 DEG C, hexane feed temperature 56 DEG C, hexane flow 34000kg/h, cyclohexanone-oxime flow
6000kg/h, preparation obtains the cyclohexanone-oxime hexane solution that cyclohexanone-oxime mass fraction is about 15wt%, the cyclohexanone-oxime prepared
Hexane solution be stored in pans, in preparation, create the polycondensation of cyclohexanone-oxime, and define black colloid, Jiao
Containing a large amount of impurity influential on caprolactam product quality in pledge, and burnt pledge has ultimately resulted in the stifled of feed-line
Plug.
Carrying out Beckmann rearrangement with it further, in gained rearrangement product, octahydro azophenlyene content is 50 μ g/g.
Embodiment 1
This example demonstrates that the method for the organic solvent of processing cycle and the preparation method of caprolactam.
By circulation hexane and temperature 20 that temperature 61 DEG C, flow 34000kg/h, octahydro azophenlyene impurity content are 0.385wt%
DEG C, the 25wt% ammonia of flow 375kg/h in stirred tank, mix contact, obtain process hexane.
The hexane of above-mentioned process is used for the preparation of the hexane solution of cyclohexanone-oxime, is formulated in the still of band stirring and carries out,
Cyclohexanone-oxime feeding temperature 92 DEG C, flow 6000kg/h, hexane feed temperature 56 DEG C, flow 34000kg/h, cyclohexanone-oxime flow
6000kg/h, preparation obtains the cyclohexanone-oxime hexane solution of about 15wt%.The solution storage prepared is in pans, in preparation,
Not having black Jiao's pledge to generate, cyclohexanone-oxime hexane solution has no pipeline blockage problem in conveyance conduit, cyclohexanone-oxime is described
There is not polycondensation.
Beckmann rearrangement is carried out further, octahydro azophenlyene content 12 μ g/g in gained rearrangement product with it.
Embodiment 2
This example demonstrates that the method for the organic solvent of processing cycle and the preparation method of caprolactam.
By circulation hexane and temperature 20 that temperature 61 DEG C, flow 34000kg/h, octahydro azophenlyene impurity content are 0.385wt%
DEG C, the 40wt% sodium hydroxide of flow 270kg/h in stirred tank, mix contact, obtain process hexane.
The hexane of above-mentioned process is used for the preparation of the hexane solution of cyclohexanone-oxime, is formulated in the still of band stirring and carries out,
Cyclohexanone-oxime feeding temperature 91 DEG C, flow 6000kg/h, hexane feed temperature 58 DEG C, flow 34000kg/h, preparation obtains about
The hexane solution of the cyclohexanone-oxime of 15wt%.The solution storage prepared is in pans, in preparation, does not has black Jiao's pledge raw
Becoming, the hexane solution of cyclohexanone-oxime has no pipeline blockage problem in conveyance conduit, illustrates that cyclohexanone-oxime does not occurs polycondensation.
Beckmann rearrangement is carried out further, octahydro azophenlyene content 10 μ g/g in gained rearrangement product with it.
Claims (10)
1. the method for the organic solvent of a processing cycle, it is characterised in that toluene method will be come from and manufacture caprolactam process
In the amidatioon liquid that obtains make the organic solution of the cyclohexanone-oxime obtained in caprolactam process with benzene legal system and contact and carry out
The organic solvent of Beckmann rearrangement reaction isolated contacts with alkaline matter, and alkaline matter addition makes to recycle
The Beckmann rearrangement reaction product that participates in of organic solvent in octahydro azophenlyene content less than 15 μ g/g.
2. according to the process of claim 1 wherein, described alkaline matter selected from sodium hydroxide, potassium hydroxide, calcium hydroxide,
One or more in sodium carbonate, calcium carbonate and ammonia.
3., according to the method for claim 1 or 2, wherein, described alkaline matter, its concentration of aqueous solution is its saturated concentration.
4. according to the process of claim 1 wherein, described organic solvent contacts with alkaline matter, and its Contact Temperature is 5-80
℃。
5., according to the process of claim 1 wherein, described alkaline matter addition makes the organic solvent recycled participate in
Beckmann rearrangement reaction product in octahydro azophenlyene content less than 10 μ g/g.
6. according to the method for claim 1,4 or 5, wherein, described organic solvent is in benzene, toluene, hexamethylene and hexane
One or more.
7., according to the process of claim 1 wherein, the organic solution of described cyclohexanone-oxime is the hexane solution of cyclohexanone-oxime,
Its concentration is 5-20wt%.
8. a preparation method for caprolactam, is that toluene method manufactures the amidatioon liquid and benzene method obtained in caprolactam process
The organic solution contact manufacturing the cyclohexanone-oxime obtained in caprolactam process carries out Beckmann rearrangement reaction isolated
Product and organic solvent, wherein, described product is again through including neutralizing, crystallize, extract and subtractive process obtaining oneself
Lactams, and described organic solvent is through recycling, it is characterised in that in the organic solution of described cyclohexanone-oxime, organic
Solvent is connecing with cyclohexanone-oxime at least partially from the organic solvent in the organic solvent recycled and described recycling
Tactile preparation first contact with a kind of alkaline matter before obtaining the organic solution of cyclohexanone-oxime so that join through the organic solvent of recycling
With Beckmann rearrangement reaction product in octahydro azophenlyene content less than 15 μ g/g.
9. the organic solvent of according to the method for claim 8, wherein, described recycling is prepared contacting with cyclohexanone-oxime
The temperature of organic solution to cyclohexanone-oxime is 0-80 DEG C.
10., according to the method for claim 8, wherein, in the organic solution of described cyclohexanone-oxime, come from recycling has
Machine solvent accounts for the 95～100% of total organic solvent.
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|---|---|---|---|---|
| US4257950A (en) * | 1978-10-16 | 1981-03-24 | Basf Aktiengesellschaft | Continuous preparation of ε-caprolactam by Beckmann rearrangement |
| CN1508128A (en) * | 2002-12-13 | 2004-06-30 | 中国石油化工股份有限公司巴陵分公司 | Method for preparing caprolactam |
| CN101434569A (en) * | 2007-11-15 | 2009-05-20 | 中国石油化工股份有限公司 | Method and equipment for preparing caprolactam from cyclohexanone oxime |
| CN102863382A (en) * | 2011-07-07 | 2013-01-09 | 中国石油化工股份有限公司 | Solvent recovery method of caprolactam rearrangement reaction products and application thereof |
| CN103012262A (en) * | 2011-09-20 | 2013-04-03 | 中国石油化工股份有限公司 | Caprolactam production method |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TW200951112A (en) * | 2008-06-13 | 2009-12-16 | China Petrochemical Dev Corp | System of recycle caprolactam form rearrangement mixture and method thereof |
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- 2014-02-27 CN CN201410069288.8A patent/CN104876782B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4257950A (en) * | 1978-10-16 | 1981-03-24 | Basf Aktiengesellschaft | Continuous preparation of ε-caprolactam by Beckmann rearrangement |
| CN1508128A (en) * | 2002-12-13 | 2004-06-30 | 中国石油化工股份有限公司巴陵分公司 | Method for preparing caprolactam |
| CN101434569A (en) * | 2007-11-15 | 2009-05-20 | 中国石油化工股份有限公司 | Method and equipment for preparing caprolactam from cyclohexanone oxime |
| CN102863382A (en) * | 2011-07-07 | 2013-01-09 | 中国石油化工股份有限公司 | Solvent recovery method of caprolactam rearrangement reaction products and application thereof |
| CN103012262A (en) * | 2011-09-20 | 2013-04-03 | 中国石油化工股份有限公司 | Caprolactam production method |
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| 己内酰胺绿色生产技术;孙斌等;《化学通报》;20111231;第74卷(第11期);第999-1003页 * |
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