CN101880383B - Process for removing 1,4-dioxane in production process of high-carbon fatty alcohol polyoxyethylene ether - Google Patents
Process for removing 1,4-dioxane in production process of high-carbon fatty alcohol polyoxyethylene ether Download PDFInfo
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Abstract
The invention relates to production method of high-carbon fatty alcohol polyoxyethylene ether, in particular to a process for removing 1,4-dioxane in the production process of the high-carbon fatty alcohol polyoxyethylene ether, which mainly solves the technical problems that the control requirements of removing the 1,4-dioxane are stringent in the prior art, resulting in the reduction of production capacity, and simultaneously, the dioxane in the final product still can not meet the requirements of ultra-low content, and the like. The invention comprises the following steps: utilizing a high-pressure polymerization reactor and taking sodium methoxide as a catalyst to obtain a high-carbon fatty alcohol polyoxyethylene ether crude product by polymerization reaction, and sucking glacial acetic acid in the crude product to neutralize; sucking in deionized water, and fully stirring, so that materials are uniformly mixed; heating up, removing an azeotrope formed by the dioxane and water in the materials in vacuum state; and entering a vacuum condenser to collect, discharging to a sewage pond to treat, after the content of the dioxane achieves standards, heating up and continuing to remove water until the measured value of water is below 1.0%, and carrying out finished product cooling and slice packaging.
Description
Technical field
The present invention relates to a kind of working method of high-carbon fatty alcohol polyoxyethylene ether, especially relate in a kind of production process of high-carbon fatty alcohol polyoxyethylene ether and deviate from 1, the technology of 4-diox.
Background technology
(be called for short peregal-O) is a kind of nonionogenic tenside commonly used to high-carbon fatty alcohol polyoxyethylene ether, soluble in water, has good level dyeing, diffusion, infiltration, emulsification, boiling-off, washs, strips and wettability, is widely used in dyeing.Other can be used as emulsifying agent, wetting Agent for Printing Inks, matrix etc. and is widely used in daily-use chemical industry industries such as makeup.
Reaction below the general employing of the working method of peregal-O at present:
In the epoxyethane ring-expansion polymerization process; Along with the variation of temperature of reaction and oxyethane import volume, simultaneously some unavoidable side reactions also can take place, the by product of generation has 1; 4-diox (abbreviation diox) makes product have certain irritating smell.
1, the 4-diox (dioxane) claim dioxane or dioxane again, and colourless liquid has peculiar smell slightly, density 1.0329, and specific refractory power 1.4175, fusing point is 11 ℃, 101.1 ℃ of boiling points with water and many immiscible organic solvents, are a kind of harmful materials.Owing to use peregal-O in a large number at cosmetic field, it directly contacts with human body, and the content of diox is controlled in universal demand strictness in used for cosmetic peregal-O product at present in the world, and general requirement is below 100ppm.
In peregal-O production process; Through a large amount of facts have proved, adopt some conversion units, through strict controlled polymerization temperature, pressure and oxyethane import volume; Can reduce the generation that generates the diox side reaction greatly; But above-mentioned control requires harsh, causes throughput to descend, and exists the De diox still can't reach the super low loading requirement in the finished product simultaneously.
Summary of the invention
The technical issues that need to address of the present invention provide in a kind of production process of high-carbon fatty alcohol polyoxyethylene ether deviates from 1; The technology of 4-diox; It mainly is to solve existing in prior technology to deviate from 1; The control of 4-diox requires harsh, causes throughput to descend, and exists the De diox still can't reach super low loading simultaneously in the finished product and requires the technical problem that waits.
Above-mentioned technical problem of the present invention mainly is able to solve through following technical proposals:
Deviate from 1 in a kind of production process of high-carbon fatty alcohol polyoxyethylene ether of the present invention, the technology of 4-diox is characterized in that:
A. utilize the high pressure polymerisation reaction kettle, sodium methylate is a catalyzer, and polyreaction obtains the high-carbon fatty alcohol polyoxyethylene ether raw product, in raw product, sucks Glacial acetic acid min. 99.5, guarantees that neutralization back pH value is in 6.0～7.0 scopes;
B. in reaction kettle, suck deionized water, the weight percent that deionized water accounts for the raw product amount is 5.0～8.0%, fully stirs, and makes mixing of materials even;
C. heat up, under the material circulation spray condition, De diox and moisture content form azeotrope in the material, are deviate from by vacuum in vacuum decompression and still;
D. deviate from De diox and moisture content azeotrope and get into vacuum cooler-condenser and collect, be disposed to sewage lagoon and handle, product detect diox content up to standard after, heat up, continue vacuum removal moisture content; Be lower than 1.0% to the moisture determination value, can carry out finished product cooling, slice packaging.
Adopting Press outer circulation spray polymerization conversion unit and sodium methylate is catalyzer; Can reduce the generation that generates the diox side reaction greatly, high-carbon fatty alcohol polyoxyethylene ether raw product pH value is adjusted to 6.0～7.0, adds an amount of water; Keep 85～95 ℃ of temperature of charge; In the still vacuum degree control-0.035～-0.085MPa, utilize the spray effect of Press outer circulation spray polymerization conversion unit, in time deviate to generate the azeotrope of De diox and moisture content formation.
As preferably, add following steps between described step c and the d: reduce vacuum tightness in the still, suck deionized water once more, the weight percent that deionized water accounts for the raw product amount is 8.0～10.0%, fully stirs; Temperature of charge in the control still continues in vacuum decompression and still, under the material circulation spray condition, to deviate from residual diox and moisture content and form azeotrope.Handle through twice decompression azeotropic, the final diox residual content of product is lower than 100ppm basically, and Special Circumstances do not reach standard, and the azeotropic that can reduce pressure is for the third time handled, and treatment process is with for the second time identical.
As preferably, more than the step that adds between step c and the d is implemented once.
As preferably, described high pressure polymerisation reaction kettle is a Press outer circulation spray polymerization conversion unit.
As preferably, the time of stirring among the described step b is 30～50min.
As preferably, heating up among the described step c makes that temperature of charge is 85～95 ℃ in the still, in the still vacuum degree control-0.035～-0.085MPa.
As preferably, after described steps d Zhong diox content is up to standard, be warmed up to 105～115 ℃, continue vacuum removal moisture content
As preferably, the vacuum tightness in the described reduction still to-below the 0.085MPa.
As preferably, the time of described stirring is 30～50min.
As preferably, in the described control still temperature of charge in 85～95 ℃ of scopes, thereby deviate from residual diox and moisture content formation azeotrope.
Therefore; The present invention has through not transforming existing high-carbon fatty alcohol polyoxyethylene ether production unit, under the situation of not additional investment, through control raw product pH value, amount of water, remove technologies such as temperature, vacuum tightness; Under Press outer circulation polymerization equipment spray condition; Can make product De diox impurity obtain splendid removing, characteristics such as it is simple to have technology, and production cost is low.
Embodiment
Through embodiment, do further bright specifically below to technical scheme of the present invention.
Embodiment 1: deviate from 1 in a kind of production process of high-carbon fatty alcohol polyoxyethylene ether of this example, the technology of 4-diox the steps include:
A. adopting Press outer circulation spray polymerization conversion unit and sodium methylate is that catalyzer makes the high-carbon fatty alcohol polyoxyethylene ether raw product, and using Glacial acetic acid min. 99.5 to regulate pH value is 6.5;
B. suck the deionized water of raw product amount 5.5% (weight ratio), 30min is stirred in circulation;
C. be warming up to 90 ℃, maintain under this state of temperature, the open vacuum device, control vacuum tightness-0.035～-the 0.085MPa scope in, under decompression spray art condition, remove diox-moisture content azeotrope; Vacuum tightness reduces to-below the 0.085MPa, suck raw product amount 8.0% deionized water (weight ratio) once more, and 30min is stirred in circulation; Heat up temperature of charge in the control still at 90 ℃, vacuum tightness-0.035～-0.085MPa, continue to remove residual diox;
D. vacuum tightness is reduced to-0.085MPa, and it is 24ppm that sampling detects diox content, continues to be warming up to 110 ℃, and vacuum removal moisture content is extremely qualified, the slice packaging finished product, and final detection result diox content is 22ppm.
Embodiment 2: deviate from 1 in a kind of production process of high-carbon fatty alcohol polyoxyethylene ether of this example, the technology of 4-diox the steps include:
A. adopting Press outer circulation spray polymerization conversion unit and sodium methylate is that catalyzer makes the high-carbon fatty alcohol polyoxyethylene ether raw product, and using Glacial acetic acid min. 99.5 to regulate high-carbon fatty alcohol polyoxyethylene ether raw product pH value is 6.2;
B. suck the deionized water of raw product amount 6.0% (weight ratio), 30min is stirred in circulation;
C. be warming up to 88 ℃, maintain under this state of temperature, the open vacuum device, control vacuum tightness-0.035～-the 0.085MPa scope in, under decompression spray art condition, remove diox-moisture content azeotrope.Vacuum tightness is reduced to below the 0.085MPa, sucks raw product amount 10.0% deionized water (weight ratio) once more, and 30min is stirred in circulation; Heat up temperature of charge in the control still at 88 ℃, vacuum tightness-0.035～-0.085MPa, continue to remove residual diox;
D. vacuum tightness is reduced to-0.085MPa, and it is 32ppm that sampling detects diox content, continues to be warming up to 110 ℃, and vacuum removal moisture content is extremely qualified, the slice packaging finished product, and final detection result diox content is 29ppm.
Embodiment 3: deviate from 1 in a kind of production process of high-carbon fatty alcohol polyoxyethylene ether of this example, the technology of 4-diox the steps include:
A. adopting Press outer circulation spray polymerization conversion unit and sodium methylate is that catalyzer makes the high-carbon fatty alcohol polyoxyethylene ether raw product, and using Glacial acetic acid min. 99.5 to regulate thick ether goods pH value is 6.4;
B. suck the deionized water of raw product amount 5.0% (weight ratio), 30min is stirred in circulation;
C. be warming up to 92 ℃, maintain under this state of temperature, the open vacuum device, control vacuum tightness-0.035～-the 0.085MPa scope in, under decompression spray art condition, remove diox-moisture content azeotrope; Vacuum tightness reduces to-below the 0.085MPa, suck raw product amount 8.0% deionized water (weight ratio) once more, and 30min is stirred in circulation.Heat up temperature of charge in the control still at 88 ℃, vacuum tightness-0.035～-0.085MPa, continue to remove residual diox;
D. vacuum tightness is reduced to-0.085MPa, and it is 42ppm that sampling detects diox content, continues to be warming up to 110 ℃, and vacuum removal moisture content is extremely qualified, the slice packaging finished product, and final detection result diox content is 41ppm.
Embodiment 4: deviate from 1 in a kind of production process of high-carbon fatty alcohol polyoxyethylene ether of this example, the technology of 4-diox the steps include:
A. adopting Press outer circulation spray polymerization conversion unit and sodium methylate is that catalyzer makes the high-carbon fatty alcohol polyoxyethylene ether raw product, and using Glacial acetic acid min. 99.5 to regulate thick ether goods pH value is 6.1;
B. suck the deionized water of raw product amount 7.5% (weight ratio), 30min is stirred in circulation;
C. be warming up to 90 ℃, maintain under this state of temperature, the open vacuum device, control vacuum tightness-0.035～-the 0.085MPa scope in, under decompression spray art condition, remove diox-moisture content azeotrope.Vacuum tightness reduces to-below the 0.085MPa, suck raw product amount 10.0% deionized water (weight ratio) once more, and 30min is stirred in circulation; Heat up temperature of charge in the control still at 93 ℃, vacuum tightness-0.035～-0.085MPa, continue to remove residual diox;
D. vacuum tightness is reduced to-0.085MPa, and it is 19ppm that sampling detects diox content, continues to be warming up to 110 ℃, and vacuum removal moisture content is extremely qualified, the slice packaging finished product, and final detection result diox content is 19ppm.
Embodiment 5: deviate from 1 in a kind of production process of high-carbon fatty alcohol polyoxyethylene ether of this example, the technology of 4-diox the steps include:
A. adopting Press outer circulation spray polymerization conversion unit and sodium methylate is that catalyzer makes the high-carbon fatty alcohol polyoxyethylene ether raw product, and using Glacial acetic acid min. 99.5 to regulate thick ether goods pH value is 6.5;
B. suck the deionized water of raw product amount 5.5% (weight ratio), 30min is stirred in circulation;
C. be warming up to 90 ℃, maintain under this state of temperature, the open vacuum device, control vacuum tightness-0.035～-the 0.085MPa scope in, under decompression spray art condition, remove diox-moisture content azeotrope.Vacuum tightness reduces to-below the 0.085MPa, suck raw product amount 8.0% deionized water (weight ratio) once more, and 30min is stirred in circulation; Heat up temperature of charge in the control still at 90 ℃, vacuum tightness-0.035～-0.085MPa, continue to remove residual diox;
D. vacuum tightness is reduced to-0.085MPa, and it is 24ppm that sampling detects diox content, continues to be warming up to 110 ℃, and vacuum removal moisture content is extremely qualified, the slice packaging finished product, and final detection result diox content is 22ppm.
Embodiment 6: deviate from 1 in a kind of production process of high-carbon fatty alcohol polyoxyethylene ether of this example, the technology of 4-diox the steps include:
A. adopting Press outer circulation spray polymerization conversion unit and sodium methylate is that catalyzer makes the high-carbon fatty alcohol polyoxyethylene ether raw product, and using Glacial acetic acid min. 99.5 to regulate thick ether goods pH value is 6.7;
B. suck the deionized water of raw product amount 6.3% (weight ratio), 30min is stirred in circulation;
C. be warming up to 86 ℃, maintain under this state of temperature, the open vacuum device, control vacuum tightness-0.035～-the 0.085MPa scope in, under decompression spray art condition, remove diox-moisture content azeotrope; Vacuum tightness reduces to-below the 0.085MPa, suck raw product amount 8.5% deionized water (weight ratio) once more, and 30min is stirred in circulation.Heat up temperature of charge in the control still at 91 ℃, vacuum tightness-0.035～-0.085MPa, continue to remove residual diox;
D. vacuum tightness is reduced to-0.085MPa, and it is 39ppm that sampling detects diox content, continues to be warming up to 110 ℃, and vacuum removal moisture content is extremely qualified, the slice packaging finished product, and final detection result diox content is 37ppm.
Embodiment 7: deviate from 1 in a kind of production process of high-carbon fatty alcohol polyoxyethylene ether of this example, the technology of 4-diox the steps include:
A. adopting Press outer circulation spray polymerization conversion unit and sodium methylate is that catalyzer makes the high-carbon fatty alcohol polyoxyethylene ether raw product, and using Glacial acetic acid min. 99.5 to regulate thick ether goods pH value is 6.5;
B. suck the deionized water of raw product amount 5.1% (weight ratio), 30min is stirred in circulation;
C. be warming up to 93 ℃, maintain under this state of temperature, the open vacuum device, control vacuum tightness-0.035～-the 0.085MPa scope in, under decompression spray art condition, remove diox-moisture content azeotrope.Vacuum tightness reduces to-below the 0.085MPa, suck raw product amount 8.0% deionized water (weight ratio) once more, and 30min is stirred in circulation; Heat up temperature of charge in the control still at 89 ℃, vacuum tightness-0.035～-0.085MPa, continue to remove residual diox;
D. vacuum tightness is reduced to-0.085MPa, and it is 56ppm that sampling detects diox content, continues to be warming up to 110 ℃, and vacuum removal moisture content is extremely qualified, the slice packaging finished product, and final detection result diox content is 50ppm.
Claims (8)
1. deviate from 1 in a production process of high-carbon fatty alcohol polyoxyethylene ether, the technology of 4-diox is characterized in that:
A. utilize the high pressure polymerisation reaction kettle, sodium methylate is a catalyzer, and polyreaction obtains the high-carbon fatty alcohol polyoxyethylene ether raw product, in raw product, sucks Glacial acetic acid min. 99.5, guarantees that neutralization back pH value is in 6.0～7.0 scopes;
B. in reaction kettle, suck deionized water, the weight percent that deionized water accounts for the raw product amount is 5.0～8.0%, fully stirs, and makes mixing of materials even;
C. heating up makes that temperature of charge is 85～95 ℃ in the still, in still vacuum degree control-0.035～-0.085MPa and still under the material circulation spray condition, De diox and moisture content formation azeotrope is deviate from by vacuum in the material;
D. deviate from De diox and moisture content azeotrope and get into vacuum cooler-condenser and collect, be disposed to sewage lagoon and handle, product detect diox content up to standard after, heat up, continue vacuum removal moisture content; Be lower than 1.0% to the moisture determination value, can carry out finished product cooling, slice packaging.
2. deviate from 1 in a kind of production process of high-carbon fatty alcohol polyoxyethylene ether according to claim 1; The technology of 4-diox; It is characterized in that adding between described step c and the d following steps: reduce vacuum tightness in the still; Suck deionized water once more, the weight percent that deionized water accounts for the raw product amount is 8.0～10.0%, fully stirs; Continuation under the material circulation spray condition, is deviate from residual diox and moisture content and is formed azeotrope in vacuum decompression and still.
3. deviate from 1 in a kind of production process of high-carbon fatty alcohol polyoxyethylene ether according to claim 2, the technology of 4-diox is more than the step enforcement once that it is characterized in that adding between described step c and the d.
4. according to deviating from 1 in claim 1 or the 2 or 3 described a kind of production process of high-carbon fatty alcohol polyoxyethylene ether, the technology of 4-diox is characterized in that described step a mesohigh polymerization reaction kettle is a Press outer circulation spray polymerization conversion unit.
5. according to deviating from 1 in claim 1 or the 2 or 3 described a kind of production process of high-carbon fatty alcohol polyoxyethylene ether, the technology of 4-diox is characterized in that the time of stirring among the described step b is 30～50min.
6. according to deviating from 1 in claim 1 or the 2 or 3 described a kind of production process of high-carbon fatty alcohol polyoxyethylene ether, the technology of 4-diox, it is characterized in that described steps d Zhong diox content is up to standard after, be warmed up to 105～115 ℃, continue vacuum removal moisture content.
7. according to deviating from 1 in claim 2 or the 3 described a kind of production process of high-carbon fatty alcohol polyoxyethylene ether, the technology of 4-diox, it is characterized in that in the described reduction still vacuum tightness to-below the 0.085MPa.
8. according to deviating from 1 in claim 2 or the 3 described a kind of production process of high-carbon fatty alcohol polyoxyethylene ether, the technology of 4-diox, the time that it is characterized in that described stirring is 30～50min.
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Application publication date: 20101110 Assignee: Hangzhou Bailang Auxiliaries Co., Ltd. Assignor: Hangzhou Electrochemical Group Auxiliary Chemical Co., Ltd. Contract record no.: 2014330000440 Denomination of invention: Process for removing 1,4-dioxane in production process of high-carbon fatty alcohol polyoxyethylene ether Granted publication date: 20120125 License type: Exclusive License Record date: 20150106 |
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Assignee: Hangzhou Bailang Auxiliaries Co., Ltd. Assignor: Hangzhou Electrochemical Group Auxiliary Chemical Co., Ltd. Contract record no.: 2014330000440 Date of cancellation: 20170316 |
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