CN101186581A - Continuous clean synthesis method for sodium iminodiacetate - Google Patents
Continuous clean synthesis method for sodium iminodiacetate Download PDFInfo
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- CN101186581A CN101186581A CNA2006100952132A CN200610095213A CN101186581A CN 101186581 A CN101186581 A CN 101186581A CN A2006100952132 A CNA2006100952132 A CN A2006100952132A CN 200610095213 A CN200610095213 A CN 200610095213A CN 101186581 A CN101186581 A CN 101186581A
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Abstract
The invention relates to an environment-friend clean method for continuously synthesizing iminodiacetic salt via hydroxyl acetonitrile method, which is characterized in that formonitrileis used as initial material to be absorbed and synthesized with formaldehyde solution to obtain hydroxyl acetonitrile water solution, the hydroxyl acetonitrile water solution and ammonia in the presence of catalyst are continuously reacted and synthesized in a segment tubular reactor to obtain iminodiacetic salt, the reaction solution via twice crystallization separations to obtain iminodiacetic salt solid, the mother liquid is concentrated and crystallized to recovery catalysts, the mother liquid is comprehensively utilized, and the hydroxyl acetonitrile in the presence of sodium-hydroxide is hydrolyzed into salt to obtain iminodiacetic salt water solution. The iminodiacetic salt water solution can be directly used to produce N-phosphono methyl imido diacetic acid to produce pesticide glyphosate finally, directly be cooled and crystallized to obtain hydroxyl acetonitrile solid with crystal water, be dewatered and dried to obtain waterless solid product, or be acidified by acid to obtain hydroxyl acetonitrile crystal.
Description
A kind of hydroxyacetonitrile serialization catalysis clean synthesis method for sodium iminodiacetate that relates to, be to be the production method of raw material production pesticide intermediate iminodiacetic acid sodium with prussic acid and formaldehyde synthetic hydroxyl acetonitrile aqueous solution, iminodiacetic acid sodium is the important intermediate of producing pesticide glyphosate, belongs to the production method of pesticide intermediate.
Iminodiacetic acid sodium (being called for short DSIDA) has another name called Diglycocol sodium, ammonia sodium oxalate, and molecular formula is HN (CH2COONa)
2The iminodiacetic acid sodium acidifying obtains iminodiethanoic acid, and iminodiethanoic acid is the important source material and the intermediate of agricultural chemicals, pharmacy, rubber, tensio-active agent, complexing agent, foodstuff additive, electroplating industry, synthetic metal finishing material and ion exchange resin etc.Domestic industry production iminodiethanoic acid (sodium salt) method mainly contains three kinds, hydrocyanic acid method, chloroactic acid method and diethanolamine method.Chloroactic acid method technical maturity wherein, but long flow path, product purity is low, cost is high, " three wastes " serious, and can only produce aqua, be tending towards eliminating route.Diethanolamine method is the diethanolamine one-step oxidation process new technology of the external exploitation nineties, China has also carried out the exploitation of this route, succeeds, existing this technology of just actively promoting, this method technical process is short, by product is few, product purity is high, and industrializing implementation is easy; Another advantage of this method is that iminodiacetic acid sodium salt can be directly used in the synthetic pesticide glyphosate, need not acidizing process, so not only reduced the iminodiethanoic acid loss, and the waste water of having avoided acidization to produce, simplified technology, very favourable to synthetic high content glyphosate; But the raw-material price of this law production Iminodiacetate is higher, and technology content is not high, and profit margin is little.The hydrocyanic acid method is one of external main method that adopts, and also is comparatively sophisticated operational path, but because the cyanide wastewater processing is cumbersome, has a strong impact on its development.In recent years, domestic owing to greatly develop the agricultural chemicals glyphosate production, competition exploitation glyphosate production technology, at first production iminodiacetonitrile of relevant manufacturer's employing hydroxyacetonitrile hydrolysis again obtains iminodiacetic acid sodium, is directly used in the regeneration of production pmida98 and produces glyphosate; The also acidificable iminodiethanoic acid that obtains: Sichuan Province's natural gas research institute developed a kind of step hydroxyacetonitrile synthesizing iminodiacetic acid (salt) nitrile again hydrolysis obtain the method for iminodiethanoic acid, this method is compared with method in the past certain advantage, but also there is very big problem in the actual production in the environmental protection, and, owing to be batch production, to realize in the big production of industry that automatization control has great difficulty.
The serialization environment-protecting clean novel process that the purpose of this invention is to provide a kind of hydroxyacetonitrile method synthesis of iminodiacetic acid salt, it is characterized in that with prussic acid being starting raw material, through absorbing the synthesis of hydroxy acetonitrile solution with formaldehyde solution, hydroxyl acetonitrile aqueous solution and ammonia under catalyst action in the sectional type tubular reactor continuous reaction synthesizing iminodiacetic acid (salt) nitrile, reaction solution obtains the iminodiacetonitrile solid by twice Crystallization Separation, mother liquor condensing crystal once more reclaims catalyzer, and last mother liquor is realized comprehensive utilization; The hydrolysis salify obtains the iminodiacetic acid sodium aqueous solution to iminodiacetonitrile in the presence of the sodium hydroxide having.This iminodiacetic acid sodium aqueous solution can be directly used in the production pmida98, produces the agricultural chemicals glyphosate at last; Also but crystallisation by cooling must contain the iminodiacetic acid sodium solid of crystal water, also can dehydrate the anhydrous solid product, simultaneously also can get the iminodiacetic acid (salt) acid crystal with acidifying.
Technological process provided by the invention is mainly carried out in two steps:
The first step: it is synthetic in the presence of catalyzer that prussic acid absorbs the hydroxyl acetonitrile aqueous solution and the ammonia that obtain with formalin, obtains iminodiacetonitrile.
i.HCN+CH
2O→HOCH
2CN
ii.2HOCH
2CN+NH
3→HN(CH
2CN)
2+2H
2O
Prussic acid directly absorbs through formalin and obtains hydroxyl acetonitrile aqueous solution, and its aqueous solution can be the aqueous solution of 10%-80% concentration, is generally 45%-55%.
Hydroxyl acetonitrile aqueous solution and ammonia is the synthetic iminodiacetonitrile that generates in the presence of catalyzer.The present invention adopts a kind of pipe examination reactor to realize the serialization building-up reactions, adopts this continuous reaction device can realize automatization control very easily, can stablize control reaction pressure, temperature and material input speed and material proportion well.Reaction pressure generally can be 0-1.0Mpa, preferably 0-0.4Mpa; Temperature of reaction is 50 ℃-140 ℃, preferably 80 ℃-120 ℃.The flow process time of material in pipe examination reactor can be 3-60 minute, and the sectional type tubular reactor that the present invention adopts divides two sections, connects with second section for first section, and second section temperature of reaction is general higher 10 ℃-40 ℃ than first section temperature of reaction.Reaction solution after synthetic directly enters crystallization kettle, obtains the iminodiacetonitrile solid through cooling, primary crystallization, separation, and this solid is directly used in down the one-step hydrolysis reaction; Separating the mother liquor that obtains is a mother liquor.A mother liquor is through concentrating, and cooling again, secondary crystal, separation obtain crude product, and crude product returns and is used for primary crystallization; Secondary mother liquid is condensing crystal once more, reclaims catalyzer, reclaims catalyzer and directly applies mechanically; Last mother liquor can burning disposal, can be used as the raw material of compound manure, also can be used as the effective constituent of Snow Agent.
Second step: the iminodiacetonitrile solid that the first step obtains, hydrolysis obtains the iminodiacetic acid sodium aqueous solution in aqueous sodium hydroxide solution.
The iminodiacetonitrile solid is dropped in the suitably excessive aqueous sodium hydroxide solution, and is heated to 70 ℃ of-120 ℃ of following hydrolysis, and hydrolysis time was generally 1-10 hour, preferably 2-5 hour.The ammonia that hydrolysis produces is recycled.
Hydrolysis finishes to obtain the aqueous solution of Iminodiacetic acid sodium salt, and this iminodiacetic acid sodium aqueous solution can be directly used in the production pmida98, produces the agricultural chemicals glyphosate at last; Also but crystallisation by cooling must contain the iminodiacetic acid sodium solid of crystal water, also can dehydrate the anhydrous solid product, simultaneously also can get the iminodiacetic acid (salt) acid crystal with acidifying, separate, dry iminodiacetic acid (salt) acid product.
Reactions steps process of the present invention is: gaseous hydrogen cyanic acid absorbs with formalin and obtains hydroxyl acetonitrile aqueous solution, hydroxyl acetonitrile aqueous solution and ammonia in the presence of the catalyzer in the sectional type tubular reactor serialization synthesize the generation iminodiacetonitrile; The tubular reactor that the present invention adopts divides two sections, connects with second section for first section, and second section temperature of reaction is general higher 10 ℃-40 ℃ than first section temperature of reaction.Reaction solution after synthetic directly enters crystallization kettle, obtains the iminodiacetonitrile solid through cooling, primary crystallization, separation, and solid is directly used in down the one-step hydrolysis reaction; Separating the mother liquor that obtains is a mother liquor.A mother liquor is through concentrating, and cooling again, secondary crystal, separation obtain crude product, and crude product returns and is used for primary crystallization; Secondary mother liquid is condensing crystal once more, reclaims catalyzer, reclaims catalyzer and directly applies mechanically; Last mother liquor can burning disposal, can be used as the raw material of compound manure, also can be used as the effective constituent of Snow Agent.The iminodiacetonitrile solid adds that hydrolysis obtains the iminodiacetic acid sodium aqueous solution in the aqueous sodium hydroxide solution again, and the ammonia recovery set that hydrolysis is emitted is used; This iminodiacetic acid sodium aqueous solution can be directly used in the production pmida98, produces the agricultural chemicals glyphosate at last; Also but crystallisation by cooling must contain the iminodiacetic acid sodium solid of crystal water, also can dehydrate the anhydrous solid product, simultaneously also can get the iminodiacetic acid (salt) acid crystal with acidifying, separate, dry iminodiacetic acid (salt) acid product.
Accompanying drawing is a process flow sheet of the present invention.
From above-mentioned reactions steps and technical process, can find out feature of the present invention:
1, patent of the present invention provide a kind of take hydrogen cyanide as initiation material, by hydroxyacetonitrile and ammonia synthesis Produce the cleaning procedure production method of iminodiacetic acid sodium. In synthesizing iminodiacetic acid (salt) nitrile process, adopt The serialization of segmented tubular reactor is synthetic, has well avoided the at high temperature decomposition of hydroxyacetonitrile, effectively The conversion ratio of raising synthetic reaction.
2, continuously synthesizing iminodiacetic acid (salt) nitrile process program has very effectively been avoided the numerous and diverse of pilot process Operation sequence greatly reduces the operational labour intensity of site technique; Reduce simultaneously equipment investment, reduction Energy consumption, saved raw material, also greatly reduce the loss of intermediate material.
3, can accomplish three-waste free discharge fully in the whole technical process, be proper environment-friendly clean Skill. Material in the system can recycled, and last mother liquor can be used for comprehensive utilization, and the height of trace Polymers and mechanical admixture can be concentrated burning disposal.
4, another feature of this technology is that iminodiacetic acid sodium salt can be directly used in the synthetic pesticide glyphosate, Need not acidizing process; So not only reduce the iminodiacetic acid loss, and avoided the acidization generation Waste water, simplified technology, very favourable to synthetic high content glyphosate.
5, this technology can the Joint Production iminodiacetic acid downstream product extremely, can be easily real An existing covering device is produced the hope of multiple product.
Embodiment:
Experimental example 1: the hydrocyanic acid gas with behind the 37% formaldehyde solution absorption cleaning, make the hydroxyl acetonitrile aqueous solution about 500g/l, add before use about 4% from controlling catalyst.
Above-mentioned hydroxyl acetonitrile aqueous solution is continuously fed in the preheater with the input speed of injection measurement pump with 5000kg/ hour, keep material to be preheating to 80 ℃, charging is in 500L volumetrical pipe examination reactor again, and bore is about 150 meters of 65 millimeters, tube side, and material enters from entrance end; At material inlet end 0.5-2.0 rice, ammonia to be mixed with hydroxyacetonitrile in pipe examination reactor with the input speed continuously feeding of volume pump with 375kg/ hour, reaction mass residence time in pipe examination reactor is about 6 minutes; First section of temperature of reaction remain on about 90 ℃, second section remain on 110 ℃, reactor pressure is about 0.3Mpa.Enter crystallization kettle through automatically controlled valve, hydroxyacetonitrile transformation efficiency 94.4% from the effusive material of outlet port.Material normal pressure dehydration in crystallization kettle, crystallisation by cooling, centrifugation, dry content are 97.1% product, yield 82.4%; One time mother liquor condensing crystal recovery crude product, secondary mother liquid condensing crystal recovery catalyzer, three mother liquors are used for Snow Agent.Condensed water is used for the dissolved hydrogen sodium oxide as hydrolyzed solution.
To go up content at 97% above iminodiacetonitrile intermediate solid, put in the aqueous sodium hydroxide solution of 30% content of excessive 10% molar weight and be hydrolyzed, hydrolysis is 4 hours under normal pressure and 80 ℃ of-110 ℃ of temperature, and reaction mass is carried out suitable evaporation concentration; Obtain the iminodiacetic acid sodium hydrated body after the cooling, hydrolysis total recovery 97.5%; The water recycling use that ammonia that hydrolysis discharges and concentration and evaporation go out.
Embodiment 2: embodiment 1 described hydroxyl acetonitrile aqueous solution is continuously fed in the preheater with the input speed of injection measurement pump with 2000kg/ hour, keep material to be preheating to 80 ℃, charging is in 500L volumetrical pipe examination reactor again, bore is about 150 meters of 65 millimeters, tube side, and material enters from entrance end; At material inlet end 0.5-2.0 rice, ammonia to be mixed with hydroxyacetonitrile in pipe examination reactor with the input speed continuously feeding of volume pump with 150kg/ hour, reaction mass residence time in pipe examination reactor is about 15 minutes; First section of temperature of reaction remain on about 95 ℃, second section keep 110 ℃, reactor pressure is about 0.3MPa.Enter crystallization kettle through automatically controlled valve, hydroxyacetonitrile transformation efficiency 98.2% from the effusive material of outlet port.Material normal pressure dehydration in crystallization kettle, crystallisation by cooling, centrifugation, dry content are 98.0% product, yield 85.2%; One time mother liquor condensing crystal recovery crude product, secondary mother liquid condensing crystal recovery catalyzer, three mother liquors are used for Snow Agent.Condensed water is used for the dissolved hydrogen sodium oxide as hydrolyzed solution.
Embodiment 3: embodiment 1 described hydroxyl acetonitrile aqueous solution is continuously fed in the preheater with the input speed of injection measurement pump with 1000kg/ hour, keep material to be preheating to 80 ℃, charging is in 500L volumetrical pipe examination reactor again, bore is about 150 meters of 65 millimeters, tube side, and material enters from entrance end; At material inlet end 0.5-2.0 rice, ammonia to be mixed with hydroxyacetonitrile in pipe examination reactor with the input speed continuously feeding of volume pump with 75kg/ hour, reaction mass residence time in pipe examination reactor is about 30 minutes; Temperature of reaction remains on about 95 ℃, and reactor pressure is about 0.3MPa.Enter crystallization kettle through automatically controlled valve, hydroxyacetonitrile transformation efficiency 98.4% from the effusive material of outlet port.Material normal pressure dehydration in crystallization kettle, crystallisation by cooling, centrifugation, dry content are 98.1% product, yield 85.4%; One time mother liquor condensing crystal recovery crude product, secondary mother liquid condensing crystal recovery catalyzer, three mother liquors are used for Snow Agent.Condensed water is used for the dissolved hydrogen sodium oxide as hydrolyzed solution.
Embodiment 4: embodiment 1 described hydroxyl acetonitrile aqueous solution is continuously fed in the preheater with the input speed of injection measurement pump with 1000kg/ hour, keep material to be preheating to 80 ℃, charging is in 500L volumetrical pipe examination reactor again, bore is about 150 meters of 65 millimeters, tube side, and material enters from entrance end; At material inlet end 0.5-2.0 rice, ammonia to be mixed with hydroxyacetonitrile in pipe examination reactor with the input speed continuously feeding of volume pump with 75kg/ hour, reaction mass residence time in pipe examination reactor is about 30 minutes; Temperature of reaction remains on about 100 ℃, and reactor pressure is about 0.3MPa.Enter crystallization kettle through automatically controlled valve, hydroxyacetonitrile transformation efficiency 98.8% from the effusive material of outlet port.Material normal pressure dehydration in crystallization kettle, crystallisation by cooling, centrifugation, dry content are 98.3% product, yield 85.7%; One time mother liquor condensing crystal recovery crude product, secondary mother liquid condensing crystal recovery catalyzer, three mother liquors are used for Snow Agent.Condensed water is used for the dissolved hydrogen sodium oxide as hydrolyzed solution.
Claims (4)
1. hydroxyacetonitrile method continuous clean synthesis method for sodium iminodiacetate, it is characterized in that with prussic acid being starting raw material, through absorbing the synthesis of hydroxy acetonitrile solution with formaldehyde solution, hydroxyl acetonitrile aqueous solution and ammonia is serialization catalysis synthesizing iminodiacetic acid (salt) nitrile in the sectional type tubular reactor, reaction solution obtains the iminodiacetonitrile solid by twice Crystallization Separation, mother liquor condensing crystal once more reclaims catalyzer, condensed water is used for dissolved hydrogen sodium oxide preparation hydrolyzed solution, and last mother liquor is realized comprehensive utilization; The hydrolysis salify obtains iminodiacetic acid sodium to iminodiacetonitrile in the presence of the sodium hydroxide having, and the ammonia recovery set that hydrolysis discharges is used.
2. according to the described continuous clean synthesis method for sodium iminodiacetate of claim 1, wherein said sectional type tubular reactor serialization catalysis synthesizing iminodiacetic acid (salt) nitrile, it is characterized in that the sectional type tubular reactor that adopts divides two sections, connect with second section for first section, second section temperature of reaction is general higher 10 ℃-40 ℃ than first section temperature of reaction; Reaction pressure is generally 0-1.0Mpa, preferably 0-0.4Mpa; Temperature of reaction is 50 ℃-140 ℃, preferably 80 ℃-120 ℃; The flow process time of material in pipe examination reactor is for being 3-60 minute.
3. according to the described continuous clean synthesis method for sodium iminodiacetate of claim 1, the Crystallization Separation of wherein said iminodiacetonitrile reaction solution, reaction solution after it is characterized in that synthesizing directly enters crystallization kettle, obtain the iminodiacetonitrile solid through cooling, primary crystallization, separation, this solid is directly used in down the one-step hydrolysis reaction; Separating the mother liquor that obtains is a mother liquor; A mother liquor is through concentrating, and cooling again, secondary crystal, separation obtain crude product, and crude product returns and is used for primary crystallization; Secondary mother liquid condensing crystal once more reclaims catalyzer, reclaims catalyzer and directly applies mechanically; Last mother liquor can burning disposal, can be used as the raw material of compound manure, also can be used as the effective constituent of Snow Agent, realizes cleaner production.
4. according to the described continuous clean synthesis method for sodium iminodiacetate of claim 1, the hydrolysis salify obtains iminodiacetic acid sodium to wherein said iminodiacetonitrile in the presence of the sodium hydroxide having, it is characterized in that the iminodiacetonitrile solid is dropped in the suitably excessive aqueous sodium hydroxide solution, and be heated to 70 ℃ of-120 ℃ of following hydrolysis, hydrolysis time was generally 1-10 hour, preferably 2-5 hour; The ammonia that hydrolysis produces is recycled; Hydrolysis finishes to obtain the aqueous solution of Iminodiacetic acid sodium salt, and this iminodiacetic acid sodium aqueous solution can be directly used in the production pmida98, produces the agricultural chemicals glyphosate at last; Also but crystallisation by cooling must contain the iminodiacetic acid sodium solid of crystal water, also can dehydrate the anhydrous solid product, simultaneously also can get the iminodiacetic acid (salt) acid crystal with acidifying, separate, dry iminodiacetic acid (salt) acid product.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102229505A (en) * | 2011-05-06 | 2011-11-02 | 四川省天然气化工研究院 | Detoxification method of iminodiacetonitrile waste residue, and biotechnological method for producing fertilizer from detoxified iminodiacetonitrile waste residue |
| CN101591267B (en) * | 2008-05-28 | 2012-06-27 | 北京紫光英力化工技术有限公司 | Clean production method for preparing iminodiacetonitrile by taking hydroxy acetonitrile as raw material |
| CN103910651A (en) * | 2014-03-10 | 2014-07-09 | 河北诺达化工设备有限公司 | Iminodiacetonitrile continuous crystallization method |
| CN107325015A (en) * | 2017-08-15 | 2017-11-07 | 阳泉煤业（集团）有限责任公司 | A kind of method that hydroxyacetonitrile serialization prepares glycine |
| CN113292453A (en) * | 2021-06-04 | 2021-08-24 | 四川能投建工集团设计研究院有限公司 | Continuous crystallization process of iminodiacetonitrile |
-
2006
- 2006-11-16 CN CNA2006100952132A patent/CN101186581A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101591267B (en) * | 2008-05-28 | 2012-06-27 | 北京紫光英力化工技术有限公司 | Clean production method for preparing iminodiacetonitrile by taking hydroxy acetonitrile as raw material |
| CN102229505A (en) * | 2011-05-06 | 2011-11-02 | 四川省天然气化工研究院 | Detoxification method of iminodiacetonitrile waste residue, and biotechnological method for producing fertilizer from detoxified iminodiacetonitrile waste residue |
| CN103910651A (en) * | 2014-03-10 | 2014-07-09 | 河北诺达化工设备有限公司 | Iminodiacetonitrile continuous crystallization method |
| CN103910651B (en) * | 2014-03-10 | 2016-01-20 | 河北诺达化工设备有限公司 | Iminodiacetonitrile continuous crystallisation technique |
| CN107325015A (en) * | 2017-08-15 | 2017-11-07 | 阳泉煤业（集团）有限责任公司 | A kind of method that hydroxyacetonitrile serialization prepares glycine |
| CN107325015B (en) * | 2017-08-15 | 2020-03-17 | 阳泉煤业（集团）有限责任公司 | Method for continuously preparing glycine from hydroxyacetonitrile |
| CN113292453A (en) * | 2021-06-04 | 2021-08-24 | 四川能投建工集团设计研究院有限公司 | Continuous crystallization process of iminodiacetonitrile |
| CN113292453B (en) * | 2021-06-04 | 2023-05-02 | 四川能投建工集团设计研究院有限公司 | Continuous crystallization process of iminodiacetonitrile |
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