CN101050191A - Method for preparing diethylacetonitrile in imino group - Google Patents
Method for preparing diethylacetonitrile in imino group Download PDFInfo
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- CN101050191A CN101050191A CN 200710049105 CN200710049105A CN101050191A CN 101050191 A CN101050191 A CN 101050191A CN 200710049105 CN200710049105 CN 200710049105 CN 200710049105 A CN200710049105 A CN 200710049105A CN 101050191 A CN101050191 A CN 101050191A
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- iminodiacetonitrile
- hydroxyacetonitrile
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Abstract
This invention provides a method for preparing iminodiacetonitrile. The method comprises: reacting hydroxyacetonitrile and 95-100 wt. % liquid ammonia to obtain iminodiacetonitrile. The method has such advantages as high yield, high product quality, and continuous and stable process.
Description
Technical field:
The present invention relates to the preparation method of iminodiacetonitrile, especially relevant with the method for the liquefied ammonia prepared in reaction iminodiacetonitrile of hydroxyacetonitrile and high density.
Background technology:
Iminodiacetonitrile (CAS 628-87-5), white or light grey needle crystal powder, fusing point: 74-76 ℃.Water-soluble, be dissolved in organic solvents such as methyl alcohol, ethanol and chloroform, inflammable poisonous.Be mainly used in the manufacturing of agricultural chemicals such as glyphosate, also be used for fields such as agricultural chemicals, synthetic resins, water treatment and electronic apparatus.
Existing preparation method about iminodiacetonitrile is more, but the part that comes with some shortcomings:
1, adopting with prussic acid, hexamethylenetetramine and formaldehyde is the method for raw material.Promptly more than 130 ℃, under the condition of 1Mpa, residence time 1-2 minute, the mixed aqueous solution of prussic acid, hexamethylenetetramine and formaldehyde is entered the tubular reactor reaction under certain pH value condition, thereby make iminodiacetonitrile.This severe reaction conditions needs liquid hydrogen cyanic acid, has bigger potential safety hazard, and simultaneously this reaction yield is low, cost height, shortcoming such as plant efficiency is low.
2, publication number CN1594281A discloses under the effect of catalyst replaced phenol and three iron halide, ammonia feeds in the hydroxyacetonitrile mixed system, pH value in the control reaction process, and make iminodiacetonitrile, this method has the yield height, the measured characteristics of matter, but shortcomings such as the skill of knocking off around here has fluctuation of service, and production capacity is low, and auxiliary material ammonium sulfate consumption is excessive.
3, it is raw material that publication number CN1830953A discloses with hydroxyacetonitrile and ammoniacal liquor, under the alchlor stablizer adds, in 120-180 ℃, pressure 0.4-1Mpa, prepared iminodiacetonitrile continuously in reaction times 0.5-3 minute, yield is higher, quality is better, but the technology instability, and quantity of three wastes is bigger, is difficult for handling.
4, US5187301 discloses the method for preparing iminodiacetonitrile with hydroxyacetonitrile and ammonia source, this method is divided continuous processing and interrupter method two clocks, but no matter be interrupter method or continuous processing, because it is very high that itself requires, and is difficult to realize industrialization, while reaction product complexity, quality product is not high, and yield is lower.
Summary of the invention:
The objective of the invention is to overcome many deficiencies of above method, a kind of high yield, high purity, the preparation method of the iminodiacetonitrile of continous-stable cheaply are provided.
The object of the present invention is achieved like this:
The preparation method of iminodiacetonitrile of the present invention, this method is to be the liquefied ammonia reaction of 95%-100% with hydroxyacetonitrile and quality percentage composition, make iminodiacetonitrile, directly use liquefied ammonia and be to bring a large amount of water in order to reduce because of ammoniacal liquor without the purpose of ammoniacal liquor, thereby improve yield one time, reduce the wastewater flow rate of aftertreatment, improve production efficiency of equipment.
The above-mentioned hydroxyacetonitrile and the equivalence ratio of liquefied ammonia are 0.8-1.3, and temperature of reaction is 100-180 ℃, and reaction pressure is 0.1-2Mpa.
Adding mass percent in the above-mentioned hydroxyacetonitrile is the 0.5-20% ammonium salt of hydroxyacetonitrile, make the hydroxyacetonitrile mixed solution, be preheated to 50-170 ℃, with 20-100 ℃ under the direct hybrid reaction of liquefied ammonia, raw material hydroxyacetonitrile mixed solution is preheated to 50-170 ℃ earlier, solution with surge capability will be formed earlier in the hydroxyacetonitrile solution, purpose is to carry out for stopping reaction, avoid because of the local too high by product that generates of the inhomogeneous pH of the causing value of high strength ammonia blended, influence yield and quality product, experimental results show that, the product iminodiacetonitrile, the raw material hydroxyacetonitrile is unstable in alkalescence and neutral environment, self-polymerization becomes dimer, tripolymer or polymer, and polymerization each other, or iminodiacetonitrile is hydrolyzed into iminodiacetic acid sodium salt, add the pH that helps being fit to reaction in the ammonium sulfate energy stopping reaction process before the reaction, avoided causing the pH value fluctuated because of ammonia enters reaction system, influence speed of response, by product increases, the assurance hydroxyacetonitrile of maximum carries out towards main reaction, reduces the generation of side reaction.The above-mentioned raw materials hydroxyacetonitrile mixes in still with ammonium sulfate earlier, and add-on is the 0.5-20% (mass percent) of hydroxyacetonitrile amount.Raw materials ammonia is the normal temperature charging, directly has with comparing with the ammoniacal liquor after the heating with the liquefied ammonia normal temperature under, reduces to bring the mother liquor water yield into and improve yield, alleviates three wastes treatment capacity, and plurality of advantages such as institute's consumption energy consumption are heated in minimizing simultaneously.The stability that experiment showed, iminodiacetonitrile is subjected to multiple factor affecting, and as pH, temperature, sunlight, air and moisture etc., the iminodiacetonitrile product property of black out, secluding air is stable.Except that top said under alkaline environment the instability of iminodiacetonitrile, the factor of temperature influence is also very big, temperature is high more, and the speed of side reaction is fast more, and the by product of generation is many more, be mainly nitrile polymer, the present invention has taked reaction process and reacted crystallisation process all to want strictness control pH value, and having reacted back pH is 2-6, enters crystallizer after the reduction temperature rapidly simultaneously, and centrifugal immediately, the dry finished product that gets, content reaches more than 98.5%.
Above-mentioned ammonium salt is at least a in ammonium sulfate, ammonium chloride, ammonium acetate, the ammonium nitrate.
Above-mentioned method is under agitation, adding mass percent in the hydroxyacetonitrile solution of 300-600g/l is the 0.01-1% stopper of hydroxyacetonitrile, adding mass percent is the ammonium salt of the 0.5-20% of hydroxyacetonitrile, mix, be that this pH of mixed value of liquid acidifying of 40%-100% is 1-6 with mass percent concentration then, be preheating to 50-170 ℃, with liquefied ammonia hybrid reaction direct with it, press the equivalence ratio charging of hydroxyacetonitrile and liquefied ammonia 0.8-1.3, temperature of reaction is controlled at 100-180 ℃, pressure-controlling is at 0.1-2Mpa, reaction times is 0.5-10 minute, adds acid solution after reaction solution comes out, and accent pH is 2-6, crystallization cooling under slowly stirring then, get the product iminodiacetonitrile behind the centrifugal drying, the polymkeric substance that further reduces in the reaction process produces, as the iminodiacetic acid (salt) nitrile polymer, the aminoacetonitriles polymkeric substance, ammonia three acetonitrile polymkeric substance and hydroxyacetonitrile polymkeric substance
Above-mentioned stopper is at least a in the substitutive derivative of Trimethyl Hydroquinone, Resorcinol, Resorcinol, pyrocatechol, dihydroxy-benzene, thereby effectively prevent the polymerization of nitriles substance, improve product yield, reduce product colourity, improve quality product, above-mentioned acid solution is at least a kind of in sulfate sulfatase, hydrochloric acid, nitric acid, the acetic acid.
Above-mentioned reaction formation adopts continuous still reaction or pipe reaction.
The inventive method principle is as follows:
NH
3+2HOCH
2CN→NH(CH
2CN)
2+2H
2O
According to the product iminodiacetonitrile of the inventive method preparation, its yield and quality all improve greatly, and cost is low, good stability, preparation process continous-stable.
Embodiment:
Embodiment 1:
Hydroxyacetonitrile with concentration 400g/L, squeeze into tubular reactor by 0.9: 1 proportioning of equivalence ratio with volume pump and ammonia pump respectively with the liquefied ammonia (quality percentage composition 99.2%) under the room temperature, the hydroxyl flow is 3000L/h, temperature of reaction is controlled at 170-180 ℃, reaction pressure is 1.0-1.2Mpa, residence time of material is 4 minutes, the reaction solution that reactor comes out enters crystallizer after the cooling rapidly by plate-type heat exchanger, successive reaction obtained red-brown solid iminodiacetonitrile 7192kg in eight hours, content 96.1%, yield 86.4% is by the analytical reaction mother liquor, this reaction conversion ratio 97.2%, mother liquor volume are 18.6m
3
Embodiment 2:
The hydroxyacetonitrile of concentration 450g/L is preheating to 170 ℃, squeeze into tubular reactor by 1: 1 proportioning of equivalence ratio with volume pump and ammonia pump respectively with the liquefied ammonia (quality percentage composition 99.2%) under the room temperature, the hydroxyl flow is 2000L/h, temperature of reaction is controlled at 170-180 ℃, reaction pressure is 1.0-1.2Mpa, residence time of material is 3.5 minutes, the reaction solution that reactor comes out enters crystallizer after the cooling rapidly by plate-type heat exchanger, successive reaction obtained pale solid iminodiacetonitrile 5543kg in eight hours, content 96.5%, yield 89.2% is by the analytical reaction mother liquor, this reaction conversion ratio 97.5%, mother liquor volume are 12.3m
3
Embodiment 3:
The hydroxyacetonitrile of concentration 380g/L is preheating to 170 ℃, squeeze into tubular reactor by 1: 1.1 proportioning of equivalence ratio with volume pump and ammonia pump respectively with the liquefied ammonia (quality percentage composition 98.7%) under the room temperature, the hydroxyl flow is 500L/h, temperature of reaction is controlled at 170-180 ℃, reaction pressure is 0.8-1.0Mpa, residence time of material is 4 minutes, the reaction solution that reactor comes out enters crystallizer after the cooling rapidly by plate-type heat exchanger, successive reaction obtained red-brown solid iminodiacetonitrile 1119kg in eight hours, content 96.4%, yield 85.2% is by the analytical reaction mother liquor, this reaction conversion ratio 98.1%, mother liquor volume are 3.1m3.
Embodiment 4:
The hydroxyacetonitrile of concentration 450g/L is squeezed into the 5000L stainless steel still that has stirring earlier, add 80kg ammonium sulfate and 1.5kg Trimethyl Hydroquinone by every cube, adding the sulfuric acid adjust pH is 5.5, mix and be preheating to 170 ℃ then, squeeze into tubular reactor by 1: 1 proportioning of equivalence ratio with volume pump and ammonia pump respectively with the liquefied ammonia (quality percentage composition 99.2%) under the room temperature, the hydroxyl flow is 3000L/h, temperature of reaction is controlled at 170-180 ℃, reaction pressure is 1.0-1.2Mpa, residence time of material is 4 minutes, the reaction solution that reactor comes out enters crystallizer after the cooling rapidly by plate-type heat exchanger, adding sulfuric acid accent pH is 2.8, successive reaction obtained canescence crystal iminodiacetonitrile 8442kg in eight hours, content 98.5%, yield 92.4% is by the analytical reaction mother liquor, this reaction conversion ratio 98.2%, mother liquor volume are 19.3m
3
Embodiment 5:
The hydroxyacetonitrile of concentration 500g/L is squeezed into the 5000L stainless steel still that has stirring earlier, add 50kg ammonium sulfate and 1.5kg Trimethyl Hydroquinone by every cube, adding the sulfuric acid adjust pH is 5.7, mix and be preheating to 170 ℃ then, squeeze into tubular reactor by 1: 1.05 proportioning of equivalence ratio with volume pump and ammonia pump respectively with the liquefied ammonia (quality percentage composition 99.2%) under the room temperature, the hydroxyl flow is 3000L/h, temperature of reaction is controlled at 165-175 ℃, reaction pressure is 1.0-1.2Mpa, residence time of material is 4.5 minutes, the reaction solution that reactor comes out enters crystallizer after the cooling rapidly by plate-type heat exchanger, adding sulfuric acid accent pH is 4, successive reaction obtained canescence crystal iminodiacetonitrile 9287kg in eight hours, content 98.2%, yield 91.2% is by the analytical reaction mother liquor, this reaction conversion ratio 98.5%, mother liquor volume are 18.5m
3
Embodiment 6:
The hydroxyacetonitrile of concentration 350g/L is squeezed into the 5000L stainless steel still that has stirring earlier, add 80kg ammonium sulfate and 1kg Trimethyl Hydroquinone by every cube, adding the sulfuric acid adjust pH is 5.5, mix and be preheating to 160 ℃ then, squeeze into tubular reactor by 0.95: 1 proportioning of equivalence ratio with volume pump and ammonia pump respectively with the liquefied ammonia (quality percentage composition 99.2%) under the room temperature, the hydroxyl flow is 3000L/h, temperature of reaction is controlled at 165-175 ℃, reaction pressure is 0.9-1.1Mpa, residence time of material is 4.5 minutes, the reaction solution that reactor comes out enters crystallizer after the cooling rapidly by plate-type heat exchanger, adding sulfuric acid accent pH is 3.5, successive reaction obtained canescence crystal iminodiacetonitrile 6404kg in eight hours, content 98.7%, yield 90.3% is by the analytical reaction mother liquor, this reaction conversion ratio 97.2%, mother liquor volume are 19.4m
3
Embodiment 7:
The hydroxyacetonitrile of concentration 400g/L is squeezed into the 5000L stainless steel still that has stirring earlier, add 50kg ammonium sulfate and 1kg Trimethyl Hydroquinone by every cube, adding the sulfuric acid adjust pH is 4.5, mix and be preheating to 160 ℃ then, do not squeeze into tubular reactor with volume pump and ammonia pump with the liquefied ammonia branch (quality percentage composition 99.5%) under the room temperature by 0.95: 1 proportioning of equivalence ratio, the hydroxyl flow is 2000L/h, temperature of reaction is controlled at 170-180 ℃, reaction pressure is 0.9-1.1Mpa, residence time of material is 3.5 minutes, the reaction solution that reactor comes out enters crystallizer after the cooling rapidly by plate-type heat exchanger, adding sulfuric acid accent pH is 3, successive reaction obtained canescence crystal iminodiacetonitrile 5050kg in eight hours, content 95.5%, yield 90.4% is by the analytical reaction mother liquor, this reaction conversion ratio 94.2%, mother liquor volume are 12.1m
3
Embodiment 8:
The hydroxyacetonitrile of concentration 450g/L is squeezed into the 5000L stainless steel still that has stirring earlier, add 80kg ammonium chloride and 1kg Trimethyl Hydroquinone by every cube, adding the hydrochloric acid adjust pH is 4.8, mix and be preheating to 170 ℃ then, squeezing into the 250L stainless steel autoclave by 0.95: 1 proportioning of equivalence ratio with volume pump and ammonia pump respectively with the liquefied ammonia (quality percentage composition 99.5%) under the room temperature reacts, and discharging continuously, the hydroxyl flow is 3000L/h, temperature of reaction is controlled at 170-180 ℃, reaction pressure is 1.0-1.2Mpa, the reaction solution that reactor comes out enters crystallizer after the cooling rapidly by plate-type heat exchanger, adding hydrochloric acid accent pH is 3.5, successive reaction obtained canescence crystal iminodiacetonitrile 8241kg in eight hours, content 98.5%, yield 90.2% is by the analytical reaction mother liquor, this reaction conversion ratio 98.1%, mother liquor volume are 19.3m
3
The various embodiments described above are that foregoing of the present invention is further described, but this should be interpreted as that subject area of the present invention only limits to the foregoing description, and all technology that realizes based on foregoing all belong to the scope of the invention.
Claims (7)
1, the preparation method of iminodiacetonitrile, this method are to be the liquefied ammonia reaction of 95%-100% with hydroxyacetonitrile and quality percentage composition, make iminodiacetonitrile.
2, the preparation method of iminodiacetonitrile as claimed in claim 1, the equivalence ratio that it is characterized in that hydroxyacetonitrile and liquefied ammonia is 0.8-1.3, and temperature of reaction is 100-180 ℃, and reaction pressure is 0.1-2Mpa.
3, the preparation method of iminodiacetonitrile as claimed in claim 1, it is characterized in that adding mass percent in hydroxyacetonitrile is the 0.5-20% ammonium salt of hydroxyacetonitrile, make the hydroxyacetonitrile mixed solution, be preheated to 50-170 ℃, with 20-100 ℃ under the direct hybrid reaction of liquefied ammonia.
4, the preparation method of iminodiacetonitrile as claimed in claim 3 is characterized in that ammonium salt is at least a in ammonium sulfate, ammonium chloride, ammonium acetate, the ammonium nitrate.
5, the preparation method of iminodiacetonitrile as claimed in claim 1, it is characterized in that under agitation, adding mass percent in the hydroxyacetonitrile solution of 300-600g/l is the 0.01-1% stopper of hydroxyacetonitrile, adding mass percent is the ammonium salt of the 0.5-20% of hydroxyacetonitrile, mix, be that this pH of mixed value of acid solution acidifying of 40%-100% is 1-6 with mass percent concentration then, be preheating to 50-170 ℃, with liquefied ammonia hybrid reaction direct with it, press the equivalence ratio charging of hydroxyacetonitrile and liquefied ammonia 0.8-1.3, temperature of reaction is controlled at 100-180 ℃, and pressure-controlling is at 0.1-2Mpa, and the reaction times is 0.5-10 minute, after coming out, reaction solution adds acid solution, accent pH is 2-6, and crystallization cooling under slowly stirring then gets the product iminodiacetonitrile behind the centrifugal drying.
6, the preparation method of iminodiacetonitrile as claimed in claim 5, it is characterized in that stopper is at least a in the substitutive derivative of Trimethyl Hydroquinone, Resorcinol, Resorcinol, pyrocatechol, dihydroxy-benzene, acid solution is at least a kind of in sulfuric acid, hydrochloric acid, nitric acid, the acetic acid.
7, the preparation method of iminodiacetonitrile as claimed in claim 5 is characterized in that reaction formation adopts continuous still reaction or pipe reaction.
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| CNB2007100491056A CN100422144C (en) | 2007-05-15 | 2007-05-15 | Method for preparing diethylacetonitrile in imino group |
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| CNB2007100491056A CN100422144C (en) | 2007-05-15 | 2007-05-15 | Method for preparing diethylacetonitrile in imino group |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101671362B (en) * | 2009-09-28 | 2012-12-12 | 安徽国星生物化学有限公司 | Process for preparing N-(phosphonomethyl) iminodiacetic acid by hydroxyacetonitrile continuous method |
| CN103787919A (en) * | 2012-12-27 | 2014-05-14 | 三达膜科技（厦门）有限公司 | Decolorizing method of iminodiacetonitrile |
| CN103910651A (en) * | 2014-03-10 | 2014-07-09 | 河北诺达化工设备有限公司 | Iminodiacetonitrile continuous crystallization method |
| 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 |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1594281A (en) * | 2004-07-05 | 2005-03-16 | 四川省天然气化工研究院 | Process for preparing iminodiacetic acid |
| CN1331844C (en) * | 2006-03-30 | 2007-08-15 | 重庆紫光化工有限责任公司 | Process for preparing iminodiacetonitrile |
-
2007
- 2007-05-15 CN CNB2007100491056A patent/CN100422144C/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101671362B (en) * | 2009-09-28 | 2012-12-12 | 安徽国星生物化学有限公司 | Process for preparing N-(phosphonomethyl) iminodiacetic acid by hydroxyacetonitrile continuous method |
| CN103787919A (en) * | 2012-12-27 | 2014-05-14 | 三达膜科技（厦门）有限公司 | Decolorizing method of iminodiacetonitrile |
| CN103787919B (en) * | 2012-12-27 | 2016-06-29 | 三达膜科技（厦门）有限公司 | A kind of discoloration method of Iminodiacetonitrile 1,1'-Imidodiacetonitrile |
| 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 |
| 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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