CN110028383A - The separation method of polyol mixture by-product - Google Patents
The separation method of polyol mixture by-product Download PDFInfo
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- CN110028383A CN110028383A CN201910326814.7A CN201910326814A CN110028383A CN 110028383 A CN110028383 A CN 110028383A CN 201910326814 A CN201910326814 A CN 201910326814A CN 110028383 A CN110028383 A CN 110028383A
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- mixture
- polyol
- liquid
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C231/00—Preparation of carboxylic acid amides
- C07C231/22—Separation; Purification; Stabilisation; Use of additives
- C07C231/24—Separation; Purification
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/74—Separation; Purification; Use of additives, e.g. for stabilisation
- C07C29/76—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D251/00—Heterocyclic compounds containing 1,3,5-triazine rings
- C07D251/02—Heterocyclic compounds containing 1,3,5-triazine rings not condensed with other rings
- C07D251/12—Heterocyclic compounds containing 1,3,5-triazine rings not condensed with other rings having three double bonds between ring members or between ring members and non-ring members
- C07D251/26—Heterocyclic compounds containing 1,3,5-triazine rings not condensed with other rings having three double bonds between ring members or between ring members and non-ring members with only hetero atoms directly attached to ring carbon atoms
- C07D251/40—Nitrogen atoms
- C07D251/54—Three nitrogen atoms
- C07D251/64—Condensation products of melamine with aldehydes; Derivatives thereof
Abstract
The present invention relates to a kind of separation methods of polyol mixture by-product.The mixture substep of dimethylformamide, trimethylol melamine and other polyols in mixture is separated by separating technology appropriate, realizes the complete resource of mixture by the present invention.Solvent in the separating technology of the invention is all recycled, and isolated product is completely used for raw materials for production, have the characteristics that it is environmentally protective, be simple and efficient.
Description
Technical field
The present invention relates to a kind of separation methods of polyol mixture by-product.
Background technique
In the production process of certain company, the mixture by-product of a large amount of polyols, the composition of the mixture are generated
For 2- methyl-1,3-propanediol, dimethylformamide, trimethylolpropane, neopentyl glycol, trimethylol melamine.The pair
Product is currently without any economic value, it is impossible to be used in the production of other products.
Polyol has a wide range of applications in fields such as multifunction polyester synthesis, crosslinking agents, such as coating
With the production of polyester, the production of amino resins, production of pulp strength reinforcing agent etc..The property of different polyols with
Purposes is different, such as 2- methyl-1, and 3-propanediol and neopentyl glycol are extraordinary polyols, have improve polyester hardness and
The excellent performance of weatherability, largely relies on import.Trimethylolpropane prepares polyol polyester since there are three hydroxyls for tool
Important source material, current domestic yield is also that supply falls short of demand.Trimethylol melamine is suitable as crosslinking agent, paper strength enhancing
Agent etc., the huge market demand, but due to the problems such as there are high-temperature oxydation discolorations, be not suitable for the production of polyester.
Since polyol has important application value and economic value, and domestic yield cannot be fully met
Therefore the market demand is effectively separated polyol mixture by-product, can not only realize the resource of by-product
Change, and there is important economic benefit.By the separation and resource utilization of polyol, waste will be realized
The double goal of zero-emission and wound benefit, has important research significance.
Summary of the invention
The object of the present invention is to provide a kind of separation methods of polyol mixture by-product.This method is will to mix
The dimethylformamide and trimethylol melamine closed in object is separated, and other ingredients in mixture are directly used in polyester
Production.
In order to achieve the above objectives, the present invention adopts the following technical scheme:
A kind of separation method of polyol mixture by-product, the mixture include 2- methyl-1,3-propanediol, diformazan
Base formamide, trimethylolpropane, neopentyl glycol and trimethylol melamine；It is characterized in that the specific steps of this method
Are as follows:
A. by polyol mixture by-product aromatic hydrocarbons extraction, stratification, upper layer are aromatic hydrocarbons and diformazan at room temperature
The mixture of base formamide, lower layer are polyol mixture I；
B. by polyol mixture I obtained by step a and saturated salt solution with the mass ratio of 1:1~1:5 at 50~80 DEG C,
It is stirred as 0.5~2h；Then it is stood at 5~25 DEG C, has solid precipitation in liquid mixture, wherein the main component of solid
For trimethylol melamine, the main component of liquid is saturated salt solution, 2- methyl-1,3-propanediol, neopentyl glycol and three
Hydroxymethyl-propane；Gained liquid is known as polyol mixtures II；
C. polyol mixtures II obtained by step b is extracted with isoamyl alcohol, at room temperature stratification, upper layer it is main
Ingredient is isoamyl alcohol, 2- methyl-1, the mixture of 3-propanediol, neopentyl glycol and trimethylolpropane, the main component of lower layer
For saturated salt solution；The mixture on upper layer is known as polyol mixtures III；
D. polyol mixtures III obtained by step c is evaporated under reduced pressure, isoamyl alcohol is removed, obtained liquid mixture
It is directly used as polyester synthesis raw material.
Above-mentioned aromatic hydrocarbons is benzene, toluene or durene.
The mass ratio of aromatic hydrocarbons and polyol mixture by-product is 1:1~3:1 in above-mentioned steps a.
The time stood at room temperature in above-mentioned steps a is 0.5~2h.
The time of repose of above-mentioned steps b is 24~72h.
The ratio of polyol mixtures II and isoamyl alcohol is mass ratio 1:1~1:3 in above-mentioned steps c, at room temperature
The time of standing is 0.5~2h.
Polyol mixture by-product is effectively separated, is obtained by separating technology appropriate by the present invention
Meet the separation product of polymerization technique requirement and can be used in the separation product of other purposes, fully achieves the resource of the by-product
Change.
Specific embodiment
The contents of the present invention are exemplified below, but not limited to the examples range.
Embodiment one
(1) needing the group of the mixture by-product of polyol to be separated becomes 2- methyl-1,3-propanediol 50.1wt%；
Dimethylformamide 7.4wt%；Trimethylolpropane 16.8wt%；Neopentyl glycol 5.7wt%；Trimethylol melamine 20wt%.
(2) separation of dimethylformamide: benzene 100g and polyol mixture 100g is sufficiently mixed at room temperature
It closes, stands 0.5h at room temperature, mixture forms apparent upper layer and lower layer, is separated upper layer and lower layer liquid with separatory funnel, will be upper
The transparency liquid 107.4g of layer is for other systems as solvent.Obtain the mixture 92.6g of lower layer, referred to as polyol
Mixture A1.
(3) separation of trimethylol melamine: polyol mixture A1 92.6g and saturated salt solution
92.6g is stirred 2 hours at 50 DEG C.Then it is stood for 24 hours under conditions of 5 DEG C, there is solid precipitation in liquid mixture.It is logical
Solid component is recovered by filtration, obtains solid 17g, gained liquid 168.2g is known as polyol mixture A2.
(4) separation of saturated salt solution: polyol mixture A2 168.2g and isoamyl alcohol 504.6g are at room temperature
It is sufficiently mixed, stands 0.5h at room temperature, mixture forms apparent upper layer and lower layer, is divided upper layer and lower layer liquid with separatory funnel
From the liquid 92.6g of lower layer to be used for the separation of process byproducts polyol mixture next time.It mixes on upper layer
Close object 580.2g, referred to as polyol mixture A3.
(5) separation of polyester synthesis raw material: polyol mixture A3 580.2g is true under conditions of 110 DEG C
Sky distillation, isoamyl alcohol 504.6g is removed, obtained liquid mixture 75.6g is directly used in the synthesis of polyester.Experiments verify that
Obtained polyester yellowish.Point of the isoamyl alcohol 504.6g for process byproducts polyol mixture next time
From.
Embodiment two
(1) needing the group of the mixture by-product of polyol to be separated becomes 2- methyl-1,3-propanediol 50.1wt%；
Dimethylformamide 7.4wt%；Trimethylolpropane 16.8wt%；Neopentyl glycol 5.7wt%；Trimethylol melamine 20wt%.
(2) separation of dimethylformamide: toluene 200g and polyol mixture 100g is sufficiently mixed at room temperature
It closes, stands 1h at room temperature, mixture forms apparent upper layer and lower layer, is separated upper layer and lower layer liquid with separatory funnel, by upper layer
Transparency liquid 207.4g for other systems as solvent.The mixture 92.6g of lower layer is obtained, referred to as polyol is mixed
Close object B1.
(3) separation of trimethylol melamine: polyol mixture B1 92.6 and saturated salt solution
185.2g is stirred 1.5 hours at 60 DEG C.Then 36h is stood under conditions of 10 DEG C, there is solid analysis in liquid mixture
Out, solid component is recovered by filtration, obtains solid 18g, can be used for the industries such as papermaking as auxiliary agent, gained liquid 259.8g claims
For polyol mixture B2.
(4) separation of saturated salt solution: polyol mixture B2 259.8g and isoamyl alcohol 520g fills at room temperature
Divide mixing, stand 1h at room temperature, mixture forms apparent upper layer and lower layer, is separated upper layer and lower layer liquid with separatory funnel, will
Separation of the liquid 185.2g of lower layer for process byproducts polyol mixture next time.The mixture on upper layer
594.6g, referred to as polyol mixture B3.
(5) separation of polyester synthesis raw material: polyol mixture B3 594.6g is true under conditions of 110 DEG C
Sky distillation, isoamyl alcohol 520g is removed, and obtained liquid mixture 74.6g is directly used in the synthesis of polyester, experiments verify that,
Obtained polyester yellowish.Separation of the isoamyl alcohol for process byproducts polyol mixture next time.
Embodiment three
(1) needing the group of the mixture by-product of polyol to be separated becomes 2- methyl-1,3-propanediol 50.1wt%；
Dimethylformamide 7.4wt%；Trimethylolpropane 16.8wt%；Neopentyl glycol 5.7wt%；Trimethylol melamine 20wt%.
(2) separation of dimethylformamide: durene 300g and polyol mixture 100g are abundant at room temperature
Mixing, stands 2h, mixture forms apparent upper layer and lower layer, is separated upper layer and lower layer liquid with separatory funnel, will be upper at room temperature
The transparency liquid 307.4g of layer is for other systems as solvent.Obtain the mixture 92.6g of lower layer, referred to as polyol
Mixture C 1.
(3) separation of trimethylol melamine: 1 92.6g of polyol mixture C and saturated salt solution
277.8g is stirred 1 hour at 70 DEG C.Then 48h is stood under conditions of 15 DEG C, there is solid precipitation in liquid mixture,
Solid component is recovered by filtration, obtains solid 19g, can be used for the industries such as papermaking as auxiliary agent, gained liquid 351.4g is known as
Polyol mixture C 2.
(4) separation of saturated salt solution: 2 351.4g of polyol mixture C and isoamyl alcohol 351.4g are at room temperature
It being sufficiently mixed, stands 2h at room temperature, mixture forms apparent upper layer and lower layer, upper layer and lower layer liquid separated with separatory funnel,
The liquid 277.8g of lower layer is used for the separation of process byproducts polyol mixture next time.The mixture on upper layer
425g, referred to as polyol mixture C 3.
(5) separation of polyester synthesis raw material: by 3 425g of polyol mixture C under conditions of 110 DEG C vacuum
Distillation, isoamyl alcohol is removed, and obtained liquid mixture 73.6g is directly used in the synthesis of polyester, experiments verify that, what is obtained is poly-
Ester yellowish.Separation of the isoamyl alcohol 351.4g for process byproducts polyol mixture next time.
Example IV
(1) needing the group of the mixture by-product of polyol to be separated becomes 2- methyl-1,3-propanediol 50.1wt%；
Dimethylformamide 7.4wt%；Trimethylolpropane 16.8wt%；Neopentyl glycol 5.7wt%；Trimethylol melamine 20wt%.
(2) separation of dimethylformamide: durene 200g and polyol mixture 100g are abundant at room temperature
Mixing, stands 1.5h at room temperature, and mixture forms apparent upper layer and lower layer, is separated upper layer and lower layer liquid with separatory funnel, will
The transparency liquid 207.4g on upper layer is for other systems as solvent.Obtain the mixture 92.6g of lower layer, referred to as polyhydroxy chemical combination
Object mixture D 1.
(3) separation of trimethylol melamine: 1 92.6g of polyol mixture D and saturated salt solution
370.4g is stirred 0.5 hour at 80 DEG C.Then 60h is stood under conditions of 20 DEG C, there is solid analysis in liquid mixture
Out, solid component is recovered by filtration, obtains solid 20g, can be used for the industries such as papermaking as auxiliary agent, gained liquid 443g is known as
Polyol mixture D 2.
(4) separation of saturated salt solution: polyol mixture D 2 443g and isoamyl alcohol 443g is abundant at room temperature
Mixing, stand 2h at room temperature, mixture forms apparent upper layer and lower layer, upper layer and lower layer liquid is separated with separatory funnel, will under
Separation of the liquid 370.4g of layer for process byproducts polyol mixture next time.The mixture on upper layer
515.6g, referred to as polyol mixture D 3.
(5) separation of polyester synthesis raw material: 3 515.6g of polyol mixture D is true under conditions of 110 DEG C
Sky distillation, isoamyl alcohol is removed, and obtained liquid mixture 72.6g is directly used in the synthesis of polyester, experiments verify that, it obtains
Polyester is colourless.Separation of the isoamyl alcohol 443g for process byproducts polyol mixture next time.
Embodiment five
(1) needing the group of the mixture by-product of polyol to be separated becomes 2- methyl-1,3-propanediol 50.1wt%；
Dimethylformamide 7.4wt%；Trimethylolpropane 16.8wt%；Neopentyl glycol 5.7wt%；Trimethylol melamine 20wt%.
(2) separation of dimethylformamide: durene 200g and polyol mixture 100g are abundant at room temperature
Mixing, stands 2h, mixture forms apparent upper layer and lower layer, is separated upper layer and lower layer liquid with separatory funnel, will be upper at room temperature
The transparency liquid 207.4g of layer is for other systems as solvent.Obtain the mixture 92.6g of lower layer, referred to as polyol
Mixture E 1.
(3) separation of trimethylol melamine: 1 92.6g of polyol mixture E and saturated salt solution 463g
It is stirred at 50 DEG C 2 hours.Then it is stood for 24 hours under conditions of 5 DEG C, has solid precipitation in liquid mixture, passed through
Filter recycling solid component, obtains solid 20g, can be used for the industries such as papermaking as auxiliary agent, gained liquid 535.6g is known as polyhydroxy
Compound mixture E2.
(4) separation of saturated salt solution: 2 535.6g of polyol mixture E and isoamyl alcohol 535.6g are at room temperature
It being sufficiently mixed, stands 2h at room temperature, mixture forms apparent upper layer and lower layer, upper layer and lower layer liquid separated with separatory funnel,
The liquid 463g of lower layer is used for the separation of process byproducts polyol mixture next time.The mixture on upper layer
608.2g, referred to as polyol mixture E 3.
(5) separation of polyester synthesis raw material: 3 608.2g of polyol mixture E is true under conditions of 110 DEG C
Sky distillation, isoamyl alcohol is removed, and obtained liquid mixture 72.6g is directly used in the synthesis of polyester, experiments verify that, it obtains
Polyester is colourless.Separation of the isoamyl alcohol 535.6g for process byproducts polyol mixture next time.
Claims (6)
1. a kind of separation method of polyol mixture by-product, which includes 2- methyl-1,3-propanediol, two
Methylformamide, trimethylolpropane, neopentyl glycol and trimethylol melamine；It is characterized in that the specific steps of this method
Are as follows:
A. by polyol mixture by-product aromatic hydrocarbons extraction, stratification, upper layer are aromatic hydrocarbons and diformazan at room temperature
The mixture of base formamide, lower layer are polyol mixture I；
B. by polyol mixture I obtained by step a and saturated salt solution with the mass ratio of 1:1~1:5 at 50~80 DEG C,
It is stirred as 0.5~2h；Then it is stood at 5~25 DEG C, has solid precipitation in liquid mixture, wherein the main component of solid
For trimethylol melamine, the main component of liquid is saturated salt solution, 2- methyl-1,3-propanediol, neopentyl glycol and three
Hydroxymethyl-propane；Gained liquid is known as polyol mixtures II；
C. polyol mixtures II obtained by step b is extracted with isoamyl alcohol, at room temperature stratification, upper layer it is main
Ingredient is isoamyl alcohol, 2- methyl-1, the mixture of 3-propanediol, neopentyl glycol and trimethylolpropane, the main component of lower layer
For saturated salt solution；The mixture on upper layer is known as polyol mixtures III；
D. polyol mixtures III obtained by step c is evaporated under reduced pressure, isoamyl alcohol is removed, obtained liquid mixture
It is directly used as polyester synthesis raw material.
2. according to the method described in claim 1, it is characterized in that the aromatic hydrocarbons is benzene, toluene or durene.
3. according to the method described in claim 1, it is characterized in that aromatic hydrocarbons and polyol mixture pair in the step a
The mass ratio of product is 1:1~3:1.
4. according to the method described in claim 1, it is characterized in that the time stood at room temperature in the step a is 0.5~2h.
5. according to the method described in claim 1, it is characterized in that the time of repose of the step b is 24~72h.
6. according to the method described in claim 1, it is characterized in that polyol mixtures II and isoamyl in the step c
The ratio of alcohol is mass ratio 1:1~1:3, and the time stood at room temperature is 0.5~2h.
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Application publication date: 20190719 |