CN102796019A - Method for environment-friendly clean production of high-purity ethylene diamine tetraacetic acid (EDTA) - Google Patents
Method for environment-friendly clean production of high-purity ethylene diamine tetraacetic acid (EDTA) Download PDFInfo
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- CN102796019A CN102796019A CN2011101380748A CN201110138074A CN102796019A CN 102796019 A CN102796019 A CN 102796019A CN 2011101380748 A CN2011101380748 A CN 2011101380748A CN 201110138074 A CN201110138074 A CN 201110138074A CN 102796019 A CN102796019 A CN 102796019A
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- sodium sulfate
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Abstract
A method for the environment-friendly clean production of high-purity ethylene diamine tetraacetic acid (EDTA) is an environment-friendly clean production method which takes sodium cyanide, formaldehyde and ethylenediamine or sodium hydroxide, glycolonitrile and ethylenediamine as main raw materials to synthesize the high-purity EDTA, and is characterized in that the acidization process of the synthetic EDTA solution is carried out by two steps, the purification decoloration treatment is carried out under the condition that a solution system is weak alkaline or approaches neutral, so the optimum effect of purification decoloration can be realized; the separation after the purification decoloration is carried out by two separation steps of centrifugal separation and fine filtration, so the relatively pure EDTA synthetic solution is obtained; the method is also characterized in that the mother solution which is produced by producing EDTA and is rich in sodium sulfate is subjected to comprehensive treatment for obtaining anhydrous sodium sulphate, the zero emission clean production method is realized, and is mainly realized through the technology that sodium sulfate hydrous crystalline solid is obtained through mother solution recovery treatment, and the byproduct of the anhydrous sodium sulphate is obtained through purification dehydration and other treatments of the sodium sulfate hydrous crystalline solid; and through recovering the sodium sulfate in the mother solution, not only can resources be saved, but also the environmental conservation of the EDTA production technology can be realized, and very good economic and social benefits are obtained.
Description
Technical field
A kind ofly relate to high-purity EDTA environment friendly clean producing method; Be meant at the environment friendly clean producing method that with sodium cyanide, formaldehyde and quadrol or sodium hydroxide, hydroxyacetonitrile and quadrol is the synthetic high-purity EDTA of main raw material; Fully take into account the recycling of mother liquor and the feature of environmental protection of production process, belong to environment-protecting clean production technology method.
Background technology
With sodium cyanide, formaldehyde and quadrol or sodium hydroxide, hydroxyacetonitrile and quadrol is that the synthetic EDTA of main raw material is the process of knowing, especially with sodium cyanide, formaldehyde and quadrol by the production technology process of the synthetic EDTA of main raw material more in the industry personage be familiar with.EDTA and sodium salt thereof are purposes and basic chemical raw materials widely thereof, have numerous manufacturers both at home and abroad; The production technology method of these manufacturers is suitable basically, and the quality product of production can both satisfy market demands basically, belongs to very sophisticated production technology process.Owing in building-up process, have the ammonia of a great deal of and sodium sulfate to generate, form the discharging of tail gas ammonia and the generation of sodium sulfate mother liquor; Will form serious source of pollution if tail gas ammonia and sodium sulfate mother liquor are not carried out good recycling.In the existing manufacturing technique process, the recovery of tail gas ammonia can be resolved basically, but the recycling of sodium sulfate mother liquor becomes a generally acknowledged difficult problem.
Summary of the invention
To the deficiency of EDTA production technology as stated; A kind of high-purity EDTA environment friendly clean producing method is proposed; Both can scale operation go out the high-purity EDTA product of high-quality; Can realize mother liquor processing reclaim(ed) sulfuric acid sodium sub product again well, make full use of resource, fully realize the feature of environmental protection of EDTA production process.
The purpose of this invention is to provide a kind of high-purity EDTA environment friendly clean producing method; It is characterized in that adopting a kind of acidization that will synthesize the synthetic liquid that obtains EDTA to be divided into two steps implements; Purification and decoloration handle be solution system be weakly alkaline or near the neutral condition under carry out, make purification and decoloration reach best effect; Separation after purification and decoloration is handled adopt first spinning more isolating mode of two step of fine filtering implement, obtain the synthetic liquid of purified relatively EDTA; Another feature is that the sodium sulfate mother liquor that is rich in of producing that EDTA produces is carried out comprehensive treating process and obtains the clean preparation method that the SODIUM SULPHATE ANHYDROUS 99PCT sub product is realized zero release, and it mainly is to obtain sodium sulfate crystalline hydrate body and sodium sulfate crystalline hydrate body by the mother liquor recycling to purify the technology that processing such as dehydration obtain the SODIUM SULPHATE ANHYDROUS 99PCT sub product and realize; The recycling of sodium sulfate in the mother liquor not only can economize on resources but also can realize the feature of environmental protection that the EDTA synthesis technique is real, and extraordinary economic benefit and social benefit are arranged.
With sodium cyanide, formaldehyde and quadrol or to be that main raw material is synthetic with sodium hydroxide, hydroxyacetonitrile and quadrol obtain the synthetic liquid of EDTA and discharge ammonia; Ammonia is recycled, and the synthetic liquid of EDTA obtains the mother liquor that the EDTA product has also produced a large amount of sodium sulfate that contains higher concentration simultaneously through acidifying, purification and decoloration, after-souring, a spinning; The mother liquor cooling is also suitably assisted to be cooled to certain temperature with refrigerated water, and sufficient crystallising obtains hydration sulfate crystal body, and spinning obtains hydration sulfate crystal body solid and mother liquor; Mother liquid recycle recycle in acidizing process of EDTA reaction solution of front, operations such as hydration sulfate crystal body solid melts, purification, dehydration, crystallization obtain SODIUM SULPHATE ANHYDROUS 99PCT by-product and mother liquor and evaporation condensed water; The SODIUM SULPHATE ANHYDROUS 99PCT product through dry, detect, pack finished product, the mother liquor recovery set is used the synthetic liquid purification and decoloration workshop section of EDTA recycled, evaporation condensed water is used for operations such as material dissolution; Whole process of production realizes zero release.
A kind of high-purity EDTA environment friendly clean producing method provided by the invention, its practical implementation step is following:
The first step: with sodium cyanide, formaldehyde and quadrol or to be that main raw material is synthetic with sodium hydroxide, hydroxyacetonitrile and quadrol obtain the synthetic liquid of EDTA and discharge ammonia
NH
2CH
2CH
2NH
2+4NaCN+4CH
2O+4H
2O→C
10H
12N
2Na
4O
8+4NH
3
Or: NH
2CH
2CH
2NH
2+ 4HOCH
2CN+4NaOH → C
10H
12N
2Na
4O
8+ 4NH
3
The involved technical matters of the building-up process of the first step is that the insider knows.In building-up process, there is more a large amount of ammonia to discharge, the ammonia of release adopts corresponding reclaiming clean treatment process to obtain purified relatively ammonia, as one of sub product of this art production process.Ammonia reclaims and purification process is disclosed technology, needn't describe in detail at this.
The synthetic liquid of second step: the EDTA obtains the EDTA product through acidifying, purification and decoloration, after-souring, a spinning, has also produced the mother liquor of a large amount of sodium sulfate that contains higher concentration simultaneously
Acidifying a: C
10H
12N
2Na
4O
8+ H
2SO
4→ C
10H
14N
2Na
2O
8+ Na
2SO
4
Synthetic liquid adopts discoloring agent purification and decolorations such as gac again after an acidifying.Synthetic liquid makes solution system from neutralize weakly alkaline or near the solution system of neutral state of strong basicity state through an acidifying, this weakly alkaline or can reach best effect near the purification and decoloration of neutral state system.As everyone knows: adopted bleaching agent bleachings such as gac by the de-inking solution system, the purification and decoloration effect is unfavorable under strong acid and strong alkali environment, even can destroy scavenging agent and discoloring agent performance.So the present technique method adopts substep acidifying technology, makes the purification and decoloration effect reach ideal state; Material pH value when acidifying after decolouring is handled generally is 6.0-14.0,8.0-10.0 preferably.
Adopt weakly alkaline or handle, can improve operating environment greatly, improved material to corrosion on Equipment property with to the security of operating process near purification and decoloration under the neutrallty condition.
Through purification and decoloration, adopt first spinning more isolating mode of secondary filter two step separate, obtain the synthetic liquid of purified relatively EDTA, remove and be rich in sodium sulfate salt especially, other impurity composition is trace extremely.EDTA solution behind this purification and decoloration carries out the acidifying second time again, and purified EDTA product is crystallized out from solution.
After-souring: C
10H
14N
2Na
2O
8+ H
2SO
4→ C
10H
16N
2O
8+ Na
2SO
4
Solution behind the purification and decoloration is carried out after-souring EDTA product sufficient crystallising is come out, adopt the mode of spinning can well the EDTA product be separated with mother liquor.The EDTA product that spinning is come out obtains purified EDTA product through drying; The quality purity of product is relatively very high, main content can reach 99.9% or more than, on industry, become high purity product.Spinning also obtains being rich in the mother liquor of sodium sulfate, this mother liquor be used for subsequent processing carry out the recycling of sodium sulfate and repeatedly the mother liquor recovery set process such as use.
The 3rd step: mother liquor cooling and the suitable refrigerated water refrigerative mode that adopts are cooled to certain temperature, and sufficient crystallising obtains hydration sulfate crystal body, and spinning obtains hydration sulfate crystal body solid and sodium sulfate mother liquor 1.The temperature of material crystallisation by cooling is generally 0 ℃ of-30 ℃ of degree, preferably 5 ℃ of-15 ℃ of degree.
Sodium sulfate mother liquor 1 directly overlaps recycle in acidizing process of EDTA reaction solution of using the front, and hydration sulfate crystal body descends the step operation to handle and obtains the SODIUM SULPHATE ANHYDROUS 99PCT product.Contain a large amount of free sulfuric acids in the mother liquor system, can be through being fully utilized in mother liquid recycle to the time acidizing process; Promptly practice thrift raw material sulphuric acid and improved operating environment again.
The 4th step: operations such as hydration sulfate crystal body solid melts, purification, dehydration, crystallization obtain SODIUM SULPHATE ANHYDROUS 99PCT by-product and sodium sulfate mother liquor 2 and evaporation condensed water.
Hydration sulfate crystal body solid is the solid that is rich in crystal water, in heat-processed, can melt to be the aqueous solution; Aqueous solution purifying treatment is obtained purified aqueous sodium persulfate solution, and revaporization thickening and crystallization obtain the crystal solution of heat; Crystal solution is carried out thermal separation and is obtained SODIUM SULPHATE ANHYDROUS 99PCT product and sodium sulfate mother liquor 2 under the maintenance comparatively high temps, separation temperature is generally 38 ℃-80 ℃, preferably 50 ℃-70 ℃; The SODIUM SULPHATE ANHYDROUS 99PCT product through dry, detect, pack finished product, sodium sulfate mother liquor 2 recovery sets are used the synthetic liquid purification and decoloration workshop section of EDTA recycled, evaporation condensed water is used for operations such as material dissolution.
Sodium sulfate mother liquor 2 covers are used the purification and decoloration operation and can EDTA product remaining in the mother liquor be recovered in the acidization, effectively raise the yield of product; Promptly practice thrift material cost and realized the zero release cleaner production again.
Technical matters process of the present invention is: a kind ofly relate to high-purity EDTA environment friendly clean producing method; Be to be the environment friendly clean producing method of the synthetic high-purity EDTA of main raw material with sodium cyanide, formaldehyde and quadrol or sodium hydroxide, hydroxyacetonitrile and quadrol; It is characterized in that adopting a kind of acidization that will synthesize the synthetic liquid that obtains EDTA to be divided into two steps implements; After the acidifying solution system be weakly alkaline or near the neutral condition under carry out purification and decoloration; Separation after purification and decoloration is handled adopt first spinning more isolating mode of two step of fine filtering implement to obtain the synthetic liquid of purified relatively EDTA, the synthetic liquid of purified EDTA carries out the mother liquor that after-souring, spinning, drying obtain high-purity EDTA product and be rich in sodium sulfate again; With the mother liquor that is rich in sodium sulfate cool off and suitably freezing and crystallizing, separate and obtain sodium sulfate crystalline hydrate body and sodium sulfate mother liquor 1, melt, purify, the dewater crystallization, separation of sodium sulfate crystalline hydrate body obtains SODIUM SULPHATE ANHYDROUS 99PCT sub product and sodium sulfate mother liquor 2; Sodium sulfate mother liquor 1 and sodium sulfate mother liquor 2 recovery sets are used in acidizing process, promptly can economize on resources and can realize the real feature of environmental protection of EDTA synthesis technique, and extraordinary economic benefit and social benefit are arranged.
Technical matters provided by the invention has following characteristic:
1, the present invention will be that the synthetic acidization that obtains the synthetic liquid of EDTA of main raw material is divided into two steps and carries out with sodium cyanide, formaldehyde and quadrol or with sodium hydroxide, hydroxyacetonitrile and quadrol; And purification and decoloration handled after an acidifying; Solution system be weakly alkaline or near the neutral condition under carry out, make purification and decoloration reach best effect; Separation after purification and decoloration is handled, adopt first spinning more isolating mode of two step of fine filtering separate, obtain the synthetic liquid of purified relatively EDTA.This is that the patent art process method is produced the assurance that obtains high purity product; Simultaneously also well improved operating environment, improved material to corrosion on Equipment property with to the security of operating process.
2, the mother liquor that is rich in sodium sulfate of EDTA Crystallization Separation obtains in the process of hydration sulfate crystal body at crystallisation by cooling, suitably adopts refrigerated water refrigerative mode to improve crystalline rate, improves plant factor; Mother liquor directly overlaps recycle in acidizing process of EDTA reaction solution of using the front, contains a large amount of free sulfuric acids in the mother liquor system, can be through being fully utilized in mother liquid recycle to the time acidizing process; Promptly practice thrift raw material sulphuric acid and improved operating environment again.
3, hydration sulfate crystal body solid in heat-processed, can melt be the aqueous solution, thickening of purifying treatment revaporization and crystallization obtain heat crystal solution; Crystal solution obtains SODIUM SULPHATE ANHYDROUS 99PCT product and mother liquor keeping carrying out thermal separation under the comparatively high temps, and whole process had not only guaranteed that sewage sulfate crystal body is pure but also fully realized the comprehensive utilization of heat energy; Mother liquor reclaims and turns back to the synthetic liquid purification and decoloration workshop section of EDTA recycled, can EDTA product remaining in the mother liquor be recovered in the acidization, effectively raises the yield of product; Not only practiced thrift material cost but also realized the zero release cleaner production.
Description of drawings
Figure of description is the schematic flow sheet of the high-purity EDTA environment friendly clean producing method that the present invention relates to.Wherein, Fig. 1 is for sodium cyanide and formaldehyde being the synthetic EDTA environment-protective process schema of main raw material; Fig. 2 is for hydroxyacetonitrile and sodium hydroxide being the synthetic EDTA environment-protective process schema of main raw material.
Embodiment
Illustrate in greater detail the present invention through embodiment below, but scope of the present invention does not receive the restriction of embodiment.
Embodiment: with the device of producing 10000 tons of EDTA per year is example, and it is following that the reaction solution that the reaction synthesis step obtains carries out last handling process:
An acidifying: the synthetic material of EDTA, acidifying sulfuric acid, sodium sulfate mother liquor 1, a sodium sulfate mother liquor 2 are dropped into an acidifying still in the calculating ratio, stir and obtain acidizing fluid one time.
Synthetic liquid material composition of EDTA and inventory are following:
Acidifying sulfuric acid composition and inventory are following:
Sodium sulfate mother liquor 1 composition and inventory are following:
Sodium sulfate mother liquor 2 compositions and inventory are following:
Acidizing fluid composition and inventory after the acidifying are following:
An acidizing fluid purification and decoloration: add the purification and decoloration treatment agent in the acidizing fluid and carry out the purification and decoloration processing, purification and decoloration treatment agent composition and inventory are following:
Be purified destainer after the purification, composition and inventory are following:
Spinning and fine filtering two steps separation obtain purified relatively purification and decoloration liquid, and composition and inventory are following:
After-souring: purification and decoloration liquid is added sulfuric acid carry out after-souring, sulfuric acid composition and inventory are following:
After-souring obtains the acidizing crystal mixed solution, and composition and inventory are following:
Spinning obtains the wet product of EDTA, and composition and inventory are following:
Obtain being rich in the mother liquor of sodium sulfate simultaneously, composition and inventory are following:
The wet product drying of EDTA obtains product, and quality product and product volume are following:
Be rich in sodium sulfate mother liquor crystallisation by cooling and obtain crystallization mixture, composition and inventory are following:
Spinning obtains hydration sulfate crystal body solid and sodium sulfate mother liquor 1, and hydration sulfate crystal body solids component and inventory are following:
Sodium sulfate mother liquor 1 composition and inventory are following:
Sodium sulfate mother liquor 1 recovery set is used in acidizing process.
The fusing of hydration sulfate crystal body, thickening, crystallization are obtained SODIUM SULPHATE ANHYDROUS 99PCT crystallization mixture and evaporation condensed water, and SODIUM SULPHATE ANHYDROUS 99PCT crystallization mixture composition is following:
Evaporation condensed water is used for the preparation of material solution and other usefulness.
The spinning of SODIUM SULPHATE ANHYDROUS 99PCT crystallization mixture obtains wet product of SODIUM SULPHATE ANHYDROUS 99PCT and sodium sulfate mother liquor 2, and wet product composition and product volume are following:
Sodium sulfate mother liquor 2 compositions and inventory are following:
Sodium sulfate mother liquor 2 recovery sets are used in the acidizing process of the synthetic liquid of EDTA.
The wet article drying of SODIUM SULPHATE ANHYDROUS 99PCT obtains the SODIUM SULPHATE ANHYDROUS 99PCT product, and quality product and product volume are following:
Claims (4)
1. one kind relates to high-purity EDTA environment friendly clean producing method; Be to be the environment friendly clean producing method of the synthetic high-purity EDTA of main raw material with sodium cyanide, formaldehyde and quadrol or sodium hydroxide, hydroxyacetonitrile and quadrol; It is characterized in that adopting a kind of acidization that will synthesize the synthetic liquid that obtains EDTA to be divided into two steps implements; After the acidifying solution system be weakly alkaline or near the neutral condition under carry out purification and decoloration; Separation after purification and decoloration is handled adopt first spinning more isolating mode of two step of fine filtering implement to obtain the synthetic liquid of purified relatively EDTA, the synthetic liquid of purified EDTA carries out the mother liquor that after-souring, spinning, drying obtain high-purity EDTA product and be rich in sodium sulfate again; The mother liquor that is rich in sodium sulfate is cooled off and freezing and crystallizing, separates and to obtain sodium sulfate crystalline hydrate body and sodium sulfate mother liquor 1, and melt, purify, the dewater crystallization, separation of sodium sulfate crystalline hydrate body obtains SODIUM SULPHATE ANHYDROUS 99PCT sub product and sodium sulfate mother liquor 2; Sodium sulfate mother liquor 1 and sodium sulfate mother liquor 2 recovery sets are used in acidizing process, not only can economize on resources but also can realize the feature of environmental protection that the EDTA synthesis technique is real, and extraordinary economic benefit and social benefit are arranged.
2. 1 said high-purity EDTA environment friendly clean producing method as requested is characterized in that the material pH value when acidifying after decolouring is handled is generally 6.0-14.0, preferably 8.0-10.0.
3. 1 said high-purity EDTA environment friendly clean producing method as requested is characterized in that the mother liquor that is rich in sodium sulfate is cooled off and suitable freezing and crystallizing, and Tc is generally 0 ℃ of-30 ℃ of degree, preferably 5 ℃ of-15 ℃ of degree.
4. 1 said high-purity EDTA environment friendly clean producing method as requested, the material system keeps comparatively high temps when it is characterized in that the SODIUM SULPHATE ANHYDROUS 99PCT Crystallization Separation, and temperature is generally 35 ℃-100 ℃, preferably 50 ℃-70 ℃.
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|---|---|---|---|
| CN2011101380748A CN102796019A (en) | 2011-05-26 | 2011-05-26 | Method for environment-friendly clean production of high-purity ethylene diamine tetraacetic acid (EDTA) |
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| CN2011101380748A CN102796019A (en) | 2011-05-26 | 2011-05-26 | Method for environment-friendly clean production of high-purity ethylene diamine tetraacetic acid (EDTA) |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103159637A (en) * | 2013-03-25 | 2013-06-19 | 国药集团化学试剂有限公司 | Method for improving quality of industrial ethylene diamine tetraacetic acid |
| CN106083630A (en) * | 2016-07-25 | 2016-11-09 | 南京化学试剂股份有限公司 | A kind of pressurization recrystallization method of ethylenediaminetetraacetic acid |
| CN107501111A (en) * | 2017-09-12 | 2017-12-22 | 潍坊滨海石油化工有限公司 | EDTA production methods |
| CN108929134A (en) * | 2018-08-10 | 2018-12-04 | 四川海莱生物科技有限公司 | A kind of EDTA salt-mixture trace element water-soluble fertilizer formula and preparation method |
-
2011
- 2011-05-26 CN CN2011101380748A patent/CN102796019A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103159637A (en) * | 2013-03-25 | 2013-06-19 | 国药集团化学试剂有限公司 | Method for improving quality of industrial ethylene diamine tetraacetic acid |
| CN103159637B (en) * | 2013-03-25 | 2015-09-09 | 国药集团化学试剂有限公司 | A kind of method promoting industrial disodium ethylene diamine tetraacetate quality |
| CN106083630A (en) * | 2016-07-25 | 2016-11-09 | 南京化学试剂股份有限公司 | A kind of pressurization recrystallization method of ethylenediaminetetraacetic acid |
| CN107501111A (en) * | 2017-09-12 | 2017-12-22 | 潍坊滨海石油化工有限公司 | EDTA production methods |
| CN108929134A (en) * | 2018-08-10 | 2018-12-04 | 四川海莱生物科技有限公司 | A kind of EDTA salt-mixture trace element water-soluble fertilizer formula and preparation method |
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Application publication date: 20121128 |