CN104974130B - A method of separation preparation 4,4- dimethyl -1,3- dioxane - Google Patents
A method of separation preparation 4,4- dimethyl -1,3- dioxane Download PDFInfo
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- CN104974130B CN104974130B CN201410132467.1A CN201410132467A CN104974130B CN 104974130 B CN104974130 B CN 104974130B CN 201410132467 A CN201410132467 A CN 201410132467A CN 104974130 B CN104974130 B CN 104974130B
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Abstract
A kind of separation preparation 4,4- dimethyl -1, the method of 3- dioxane, first the raw material including formaldehyde, isobutene, acid catalyst, polymerization inhibitor is reacted in high-pressure bottle, then by reaction product rectifying, respectively obtain the kettle liquid of 4,4- dimethyl-1,3-dioxane, aqueous solution, the high-boiling components containing by-product；Use the 4,4- dimethyl -1,3- dioxane in I fatty alcohol extraction and recovery aqueous solution of extractant；Using II aliphatic hydrocarbon of extractant and fatty alcohol mixture extraction, the kettle liquid of the high-boiling components containing by-product, obtains the extract liquor containing high-boiling components, and the raffinate containing acid catalyst；The present invention not only optimizes reaction condition and step in preparation process, and further improves production efficiency of the invention to subsequent removal process, reduces production cost.
Description
Technical field
The present invention relates to a kind of methods for separating and preparing 4,4- dimethyl -1,3- dioxane.
Background technique
4,4- dimethyl -1,3- dioxane is the intermediate of olefine aldehydr method synthesis isoprene.
Isoprene be produce styrene-isoprene-phenylethene thermoplastic elastomer (TPE), polyisoprene rubber it is important
Raw material, the production method of isoprene includes pyrolysis C 5 extractive distillation method, dehydriding, chemical synthesis etc. at present.Wherein
Chemical synthesis includes isobutene-formaldehyde method, acetylene-acetone method, propylene dimerization etc..Isoamyl two is synthesized with formaldehyde by isobutene
The method of alkene has industrialized.The reaction process is usually to be realized by two-step mode technique, and the first step is isobutene and first
Aldehyde generates 4,4- dimethyl-1,3-dioxane under acidic catalyst, and second step is that 4,4- dimethyl-1,3-dioxane exists
It is decomposed under catalyst action and generates isoprene, formaldehyde, water.
Patent GB825034 has separated one kind and has prepared 4,4- dimethyl -1,3- dioxy under acid catalysis by isobutene and formaldehyde
The method of six rings, patent US2962507 separated it is a kind of using the C4 component gas containing isobutene as raw material and formaldehyde in acid
The method that reaction generates 4,4- dimethyl-1,3-dioxane under catalyst, the patents such as US3773847, US3972955 also disclose
The manufacturing method of 4,4- dimethyl -1,3- dioxane.But the deficiency of above-mentioned patent be generate 12% in reaction process~
20% high-boiling components, these high-boiling components and 4,4- dimethyl-1,3-dioxane are very difficult to separate, and result in 4,4- dimethyl-
The purity and yield of 1,3- dioxane is not high.
Patent CN200810013740 discloses the preparation method of one kind 4,4- dimethyl -1,3- dioxanes, isobutene, first
Aldehyde, acid catalysis, auxiliary agent react in a sealed container, then extract reaction product with hexamethylene, then extract liquor is distilled to obtain
4,4- dimethyl -1,3- dioxanes, the patent after completion of the reaction, directly extract the high-boiling components in kettle liquid using hexamethylene,
Extraction efficiency is not high, we verify the embodiment of the patent, it is found that there are still a large amount of height in product extracted
Object is boiled, remaining acidic catalyst can not be reused after extraction, and there is also a large amount of products not to carry out at recycling in water phase
Reason, causes the waste of resource.
Summary of the invention
It is a large amount of high boiling it is an object of the invention to be directed to 4,4- dimethyl-1,3-dioxane low yield in the prior art
The separation of object difficulty, product the status of low yield provide one kind by optimization reaction condition and step and subsequent recycling step
Yield is high, efficiently separates high-boiling components, thus separation preparation 4,4- dimethyl -1,3- dioxy that acidic catalyst can be recycled
The method of six rings.
In order to achieve the above objectives, the present invention adopts the following technical scheme:
A kind of method of separation preparation 4,4- dimethyl-1,3-dioxane, will include formaldehyde, isobutene, acid catalyst,
Raw material including polymerization inhibitor reacts in high-pressure bottle, then by reaction product rectifying, respectively obtains 4,4- dimethyl -1,3- bis-
The kettle liquid of six ring of oxygen, aqueous solution, the high-boiling components containing by-product；Use the 4,4- diformazan in I fatty alcohol extraction and recovery aqueous solution of extractant
Base -1,3- dioxane；Using II aliphatic hydrocarbon of extractant and fatty alcohol mixture extraction, the kettle liquid of the high-boiling components containing by-product, is contained
The extract liquor of high-boiling components, and the raffinate containing acid catalyst；The choosing of fatty alcohol independently in extractant I or extractant II
From n-butanol, sec-butyl alcohol, n-amyl alcohol, 2- methyl butanol, isoamyl alcohol, sec-amyl alcohol, 3- amylalcohol, tert-pentyl alcohol, hexanol, enanthol, octanol
Or one or more of isooctanol；In extractant II, the aliphatic hydrocarbon is selected from hexane, heptane, octane, hexamethylene or methyl
One or more of hexamethylene；The volume ratio of aliphatic hydrocarbon and fatty alcohol is 3: 7~7: 3.
The extractant II is preferably selected from n-hexane and n-amyl alcohol, hexamethylene and n-butanol, hexahydrotoluene and different pungent
One of alcohol, octane and mixture of hexanol.
In extractant II, the volume ratio of the aliphatic hydrocarbon and the fatty alcohol is preferably 4: 6~6: 4.
The preferred volume ratio of the extractant I and aqueous solution is 1~3: 1.
The reaction temperature is 90 DEG C~105 DEG C, and pressure is 1.5MPa~2.5MPa.
The acid catalyst is preferably phosphoric acid or sulfuric acid；Polymerization inhibitor be preferably selected from 4,6- dinitro -2- sec-butyl phenol,
One or more of p-tert-Butylcatechol or diethyl hydroxylamine.
The molar ratio 1.5~15 of the formaldehyde and isobutene.
If using phosphoric acid as catalyst, phosphoric acid it is pure it is heavy account for the 4.0%~7.0% of reaction system gross weight, if using sulfuric acid
As catalyst, then sulfuric acid is pure heavy accounts for the 1.0%~2.0% of reaction system gross weight；
The quality of the polymerization inhibitor accounts for the 0.1%~0.5% of reaction system gross mass.
The mass ratio of formaldehyde and water is 1~2:2.5 in reaction system.
The preferred embodiment of the reaction product rectifying are as follows: atmospheric distillation, 80~150 DEG C of bottom temperature, tower top temperature 50~
100 DEG C, reflux ratio 0.5~2.
When extracting the kettle liquid of the high-boiling components containing by-product using extractant II, obtains the extract liquor containing high-boiling components and contain acid catalysis
Raffinate containing acid catalyst is added in reaction process and is recycled by the raffinate of agent.
The distillation extraction liquid preferably at 60~190 DEG C after extraction, thus recycling design, isolated high-boiling components.
Aqueous solution is extracted using extractant I, then recycles the rectifying at 110~137 DEG C of obtained extract liquor in aqueous solution
4,4- dimethyl -1,3- dioxane.
Beneficial effects of the present invention
The present invention reacted under acid catalysis first against isobutene with formaldehyde in have the generation of a large amount of by-product high-boiling components cause with
Product is difficult to separate this problem, by optimizing the reaction condition and step of entire separation preparation process, so as to reduce height
The generation of object is boiled, 4,4- dimethyl-1,3-dioxane yield is improved.In addition, being different from the prior art straight after the reaction
Connect extraction, the present invention first passes through rectifying upon reaction completion and carries out product separation, obtain 4,4- dimethyl-1,3-dioxane,
The kettle liquid of aqueous solution, the high-boiling components containing by-product uses 4,4- dimethyl -1,3- in I fatty alcohol extraction and recovery aqueous solution of extractant
Dioxane, using II aliphatic hydrocarbon of extractant and fatty alcohol mixture extraction, the kettle liquid of the high-boiling components containing by-product, is obtained containing high-boiling components
Extract liquor, and the raffinate containing acid catalyst recycled completely to be conducive to the subsequent product to acquisition, in addition,
Raffinate containing acid catalyst, which may return in preparation step, to be recycled.Above-mentioned each step is combined closely through the invention,
The final product and good separating effect for obtaining high yield.
Specifically, by many experiments, the combination of suitable aliphatic hydrocarbon and fatty alcohol is selected to extract during subsequent recovery
The kettle liquid for taking the high-boiling components containing by-product improves the separative efficiency of high-boiling components in kettle liquid, the raffinate containing acid catalyst in the present invention
Middle high-boiling components remaining quantity is low, can be reduced in the catalyst solution by detecting the raffinate having containing high-boiling components 0.61%, make remaining
Acidic catalyst in raffinate can be recycled；Production cost is also saved simultaneously.Moreover, the present invention is by into one
Step handles aqueous solution, and further recycling has obtained 4, the 4- dimethyl-1,3-dioxane product in aqueous solution, improves
The yield of product.The present invention not only optimizes reaction condition and step in separation preparation process, and to subsequent removal process
Further improve production efficiency of the invention, reduce production cost.
Specific embodiment
The following examples will be to further instruction of the present invention, but the range being not intended to limit the present invention.
Comparative example 1
37% formalin 130.3g, 99.5% isobutene 35.5g, 85% phosphoric acid are added in high-pressure bottle
27.9g, o-nitrophenol 1.88g, strong stirring extract reaction product 480ml hexamethylene after 80 DEG C of reaction 2h in three times
It takes.Then extract liquor is distilled, obtains 4,4- dimethyl-1,3-dioxane 60.8g, high-boiling components 1.5g, product yield
65.3%。
Embodiment 1
37% formalin 150.0g, 99.5% isobutene 52.3g, 85% phosphoric acid are added in high-pressure bottle
12.8g 4,6- dinitro -2- sec-butyl phenol 0.43g, react 50 minutes under 95 DEG C, 2.0MPa pressure, and reaction product is normal
Rectifying is pressed, 80~150 DEG C of bottom temperature, 50~100 DEG C of tower top temperature, reflux ratio 1 obtains 4,4- dimethyl -1,3- dioxy six
Ring 75.5g, aqueous solution 125.3g, the high-boiling components containing by-product kettle liquid 22.6g, measure aqueous solution in contain 4,4- dimethyl -1,3- bis-
Six ring 16.8% of oxygen contains high-boiling components 38.4% in kettle liquid, and aqueous solution is extracted with n-amyl alcohol, wherein the volume of aqueous solution and n-amyl alcohol
4, the 4- dimethyl-1,3-dioxane in aqueous solution is recycled in 110~137 DEG C of rectifying than being 1: 2, then by extract liquor
20.5g, is obtained 4,4- dimethyl-1,3-dioxane 96.0g, yield 89.5%, dimethyl -1 containing 4,4- in raffinate water phase,
3- dioxane 0.48%.The kettle liquid n-hexane of the high-boiling components containing by-product and the combination solution of n-amyl alcohol extract, n-hexane and positive penta
The volume ratio 1: 1 of alcohol, extract liquor distill at 60~140 DEG C, isolated high-boiling components 8.6g, the catalyst solution of raffinate
13.5g is measured in the catalyst solution of raffinate containing high-boiling components 0.61%.
Embodiment 2
Identical experiment condition is used with embodiment 1, but phosphoric acid changes the catalyst solution of the recycling of embodiment 1 into, by phase
After same operating method, 4,4- dimethyl-1,3-dioxane 94.5g, product yield 88.1% are obtained.
Embodiment 3
37% formalin 150.0g, 99.5% isobutene 52.3g, 98% sulfuric acid 4.1g are added in high-pressure bottle,
P-tert-Butylcatechol 0.40g reacts 60 minutes under 90 DEG C, 1.5MPa pressure, by reaction product rectifying, obtains 4,4- bis-
Methyl-1, the kettle liquid of 3- dioxane, aqueous solution, the high-boiling components containing by-product, aqueous solution extracting n-butyl alcohol, aqueous solution and n-butanol
Volume ratio be 1: 3, then by extract liquor in 110~137 DEG C of rectifying, recycle 4,4- dimethyl -1,3- dioxy six in aqueous solution
4,4- dimethyl-1,3-dioxane 95.5g, product yield 89.0%, the kettle liquid hexamethylene of the high-boiling components containing by-product is obtained in ring
The extraction of the combination solution of alkane and n-butanol, the volume ratio 1: 1.5 of hexamethylene and n-butanol, extract liquor are distilled at 60~140 DEG C, point
High-boiling components 7.0g, the catalyst solution 4.6g of raffinate are separated out, is measured in the catalyst solution of raffinate containing high-boiling components 0.85%.
Embodiment 4
37% formalin 150.0g, 99.5% isobutene 60.0g, 85% phosphoric acid are added in high-pressure bottle
18.5g, 4,6- dinitro -2- sec-butyl phenol 0.23g, diethyl hydroxylamine 0.23g, reacts 40 under 105 DEG C, 2.5MPa pressure
Minute, by reaction product rectifying, obtain the kettle liquid of 4,4- dimethyl-1,3-dioxane, aqueous solution, the high-boiling components containing by-product, water
Solution is extracted with isooctanol, and the volume ratio of aqueous solution and isooctanol is 1: 1, then by extract liquor in 110~137 DEG C of rectifying, recycling
4,4- dimethyl-1,3-dioxane 95.0g, product yield is obtained in 4,4- dimethyl-1,3-dioxane in aqueous solution
Be 88.6%, the combination solution of the kettle liquid hexahydrotoluenes of the high-boiling components containing by-product and isooctanol extracts, hexahydrotoluene with it is different pungent
The volume ratio of alcohol is 1.5: 1, and high-boiling components 6.8g, the catalyst solution 19.5g of raffinate are isolated in 90~190 DEG C of extract liquor distillations,
It measures and contains high-boiling components 0.79% in the catalyst solution of raffinate.
Embodiment 5
37% formalin 150.0g, the isobutene 114.3g containing isobutene 45.5%, 85% are added in high-pressure bottle
Phosphatase 11 4.2g, p-tert-Butylcatechol 0.21g, diethyl hydroxylamine 0.21g react 50 points under 95 DEG C, 2.0MPa pressure
Reaction product rectifying is obtained the kettle liquid of 4,4- dimethyl-1,3-dioxane, aqueous solution, the high-boiling components containing by-product by clock, water-soluble
Liquid is extracted with n-amyl alcohol, and the volume ratio of aqueous solution and n-amyl alcohol is 1: 2, then by extract liquor in 110~137 DEG C of rectifying, recycle-water
4,4- dimethyl-1,3-dioxane in solution, is obtained 4,4- dimethyl-1,3-dioxane 94.2g, yield 87.8%,
The kettle liquid n-hexane of the high-boiling components containing by-product and the combination solution of n-amyl alcohol extract, the volume ratio 1: 1 of n-hexane and n-amyl alcohol, extraction
It takes liquid to distill at 60~140 DEG C, isolates high-boiling components 7.2g, the catalyst solution 15.0g of raffinate, the catalyst for measuring raffinate is molten
Contain high-boiling components 0.92% in liquid.
Comparative example 2
Identical experiment condition is used with embodiment 1, n-hexane and n-amyl alcohol are only changed to hexamethylene, process is identical
After operating method, measure in the catalyst solution of raffinate containing high-boiling components 15.27%.
Comparative example 3
Identical experiment condition is used with embodiment 1, the volume ratio of n-hexane and n-amyl alcohol is only changed to 8: 2, as a result
Extractant dissolves each other with kettle liquid, can not separate high-boiling components and catalyst.
Claims (9)
1. a kind of method of separation preparation 4,4- dimethyl-1,3-dioxane, which is characterized in that will include formaldehyde, isobutene,
Raw material including acid catalyst, polymerization inhibitor reacts in high-pressure bottle, then by reaction product rectifying, respectively obtains 4,4- diformazan
The kettle liquid of base -1,3- dioxane, aqueous solution, the high-boiling components containing by-product；Using in I fatty alcohol extraction and recovery aqueous solution of extractant
4,4- dimethyl -1,3- dioxane；The kettle of the high-boiling components containing by-product using II aliphatic hydrocarbon of extractant and fatty alcohol mixture extraction
Liquid obtains the extract liquor containing high-boiling components, and the raffinate containing acid catalyst；I fatty alcohol of extractant is selected from n-butanol, Zhong Ding
One in alcohol, n-amyl alcohol, 2- methyl butanol, isoamyl alcohol, sec-amyl alcohol, 3- amylalcohol, tert-pentyl alcohol, hexanol, enanthol, octanol or isooctanol
Kind is several；Extractant II is selected from one of following aliphatic hydrocarbon and the combination of fatty alcohol: n-hexane and n-amyl alcohol, hexamethylene and
The volume ratio of n-butanol, hexahydrotoluene and isooctanol, octane and hexanol, the aliphatic hydrocarbon and the fatty alcohol is 4: 6~6:
4。
2. the method according to claim 1, wherein the volume ratio of the extractant I and aqueous solution is 1~3: 1.
3. pressure is the method according to claim 1, wherein the reaction temperature is 90 DEG C~105 DEG C
1.5MPa~2.5MPa.
4. the method according to claim 1, wherein the acid catalyst is phosphoric acid or sulfuric acid；Polymerization inhibitor choosing
From one or more of 4,6- dinitro -2- sec-butyl phenol, p-tert-Butylcatechol or diethyl hydroxylamine.
5. the method according to claim 1, wherein the molar ratio 1.5~15 of the formaldehyde and isobutene.
6. according to the method described in claim 4, it is characterized in that, if using phosphoric acid as catalyst, phosphoric acid it is pure it is heavy account for it is anti-
The 4.0%~7.0% of system gross weight is answered, if using sulfuric acid as catalyst, sulfuric acid is pure heavy to account for the 1.0% of reaction system gross weight
~2.0%；
The quality of the polymerization inhibitor accounts for the 0.1%~0.5% of reaction system gross mass.
7. method according to claim 1-6, which is characterized in that the concrete mode of the reaction product rectifying
Are as follows: atmospheric distillation, 80~150 DEG C of bottom temperature, 50~100 DEG C of tower top temperature, reflux ratio 0.5~2.
8. method according to claim 1-6, which is characterized in that extract high-boiling components containing by-product using extractant II
Kettle liquid when, obtain the extract liquor containing high-boiling components and the raffinate containing acid catalyst, will containing the raffinate of acid catalyst be added
It is recycled in reaction process.
9. method according to claim 1-6, which is characterized in that using the extraction aqueous solution of extractant I, then will
4, the 4- dimethyl-1,3-dioxane in aqueous solution is recycled in the extract liquor arrived rectifying at 110~137 DEG C.
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| CN101220019A (en) * | 2008-01-04 | 2008-07-16 | 烟台万华华信合成革有限公司 | Production method of diethyleno dioxide |
| CN102816048A (en) * | 2012-09-04 | 2012-12-12 | 华东理工大学 | Method for extracting and separating 1,3-propanediol from fermentation liquid |
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| CN101220019A (en) * | 2008-01-04 | 2008-07-16 | 烟台万华华信合成革有限公司 | Production method of diethyleno dioxide |
| CN102816048A (en) * | 2012-09-04 | 2012-12-12 | 华东理工大学 | Method for extracting and separating 1,3-propanediol from fermentation liquid |
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