CN105481717B - A kind of preparation method of cyanoacetic acid and its derivative - Google Patents
A kind of preparation method of cyanoacetic acid and its derivative Download PDFInfo
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- CN105481717B CN105481717B CN201510810110.9A CN201510810110A CN105481717B CN 105481717 B CN105481717 B CN 105481717B CN 201510810110 A CN201510810110 A CN 201510810110A CN 105481717 B CN105481717 B CN 105481717B
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
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- C07C253/00—Preparation of carboxylic acid nitriles
- C07C253/30—Preparation of carboxylic acid nitriles by reactions not involving the formation of cyano groups
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- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
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- C07C253/14—Preparation of carboxylic acid nitriles by reaction of cyanides with halogen-containing compounds with replacement of halogen atoms by cyano groups
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- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/08—Preparation of carboxylic acids or their salts, halides or anhydrides from nitriles
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- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/08—Preparation of carboxylic acid esters by reacting carboxylic acids or symmetrical anhydrides with the hydroxy or O-metal group of organic compounds
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/18—Preparation of carboxylic acid esters by conversion of a group containing nitrogen into an ester group
- C07C67/22—Preparation of carboxylic acid esters by conversion of a group containing nitrogen into an ester group from nitriles
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Abstract
The invention discloses the preparation method of a kind of cyanoacetic acid and its derivative, the mixed solution of cyanoacetic acid and sodium chloride is separated into cyanoacetic acid solution and sodium chloride solution by continuous chromatography, obtain chloride ion content low cyanoacetic acid solution or high content of solid cyanoacetic acid product and its derivative, it is to avoid the cyanoacetic acid that traditional distillation and concentration separation is caused largely is decomposed, the shortcoming that yield is low.Simple to operate, production cost of the invention is low, product yield is high, quantity of three wastes is few, is a kind of production method of environment-protecting clean, obtains chloride ion content low cyanoacetic acid solution or high content of solid cyanoacetic acid product and its derivative.
Description
Technical field
The invention belongs to organic chemical synthesis and separation technology field, it is related to the preparation side of a kind of cyanoacetic acid and its derivative
Method.
Background technology
Cyanoacetic acid is production medicine, dyestuff, the important intermediate of agricultural chemicals, for producing malonic acid, cyanoacetate, malonic acid
Ester, Mecrilate, vitamin B6, caffeine and frost urinate the production of cyanogen.
Traditional production technology is that, using monoxone, sodium carbonate, Cymag as raw material, neutralized, cyaniding, acidifying, decompression are de-
Water and obtain.But the content of the solid cyanoacetic acid product obtained by this method only has 90% or so, wherein moisture and salt
Content is higher, is restricted its application.Because cyanoacetic acid concentration is low in cyanoacetic acid mixed solution, the content of water and salt
Height, therefore concentration process need to consume substantial amounts of steam, and after evaporation the phase largely separate out because of sodium chloride, poor heat transfer easily makes
Cyanoacetic acid is decomposed.
To solve the problem of low steam consumption of cyanoacetic acid concentration is big, CN201110275736.6 discloses a kind of cyanoacetic acid
Preparation method, replace hydrochloric acid to neutralize cyanoacetic acid sodium solution with hydrogen chloride gas, thus reduce water addition improve
The content of cyanoacetic acid, greatly reduces steam consumption, so as to reduce production cost.
The problem of later stage salt content is high, cyanoacetic acid is decomposed is concentrated by evaporation to solve cyanoacetic acid solution,
CN201110275737.0 discloses a kind of method of preparing cyanoacetic acid through continuous dehydration, by monoxone is neutralized, cyaniding, is acidified
After the cyanoacetic acid aqueous solution, it is coupled continuous dehydration using multiple-effect evaporation and forced-circulation evaporation, and removed not in dehydration
The disconnected sodium chloride separated out prepares the cyanoacetic acid, and cyanoacetic acid is prepared with multiple-effect evaporation, not only steam consumption is reduced, and each effect
Sodium chloride is all filtered during progress, so, the sodium chloride of precipitation can be filtered to remove in time, reduced solid-to-liquid ratio, be more beneficial for
The selection of equipment is filtered, simple to operate, utilization rate of equipment and installations is high, steam consumption is low and because dewatering time is short, cyanoacetic acid yield
Height, obtains content for 70% or so cyanoacetic acid finished product, cyanoacetic acid yield is more than 98%.CN201410041825.8 is by cyanogen second
Be passed through hydrogen chloride gas in the mixed liquor of acid and sodium chloride separates out sodium chloride using common-ion effect, then filters desalination, so
Methanol and sulfuric acid are added afterwards carry out esterification and obtain dimethyl malenate, it is to avoid the cyanogen that traditional distillation and concentration desalination is caused
The shortcoming that acetic acid is largely decomposed, yield is low, while esterification can reduce the consumption and waste water yield of sulfuric acid after desalination, operation
Simply, production cost is low, product yield is high, is adapted to scale industrial production diethyl malonate.But salt in cyanoacetic acid solution
Acid concentration is high, easily cyanoacetic acid is hydrolyzed into malonic acid in concentration process, although do not influence the later stage to synthesize malonate, but if
Directly concentration production cyanoacetic acid will result in that yield is low, malonic acid and the problems such as high chlorion in product.
CN200810052135.7 discloses a kind of preparation method of high purity solid cyanoacetic acid：Monoxone is by neutralization, cyaniding, salt
Acid neutralizes the mixture for obtaining cyanoacetic acid and sodium chloride；Then above-mentioned mixed solution is extracted with esters solvent, extract
Reduction vaporization is concentrated to give high-purity solid cyanoacetic acid.But organic solvent amount used is big, and (ratio of solvent and mixed liquor is 1-
5:1), extraction times 4-8 times, cumbersome, cost is high.
The content of the invention
It is an object of the invention to provide a kind of simple to operate, production cost is low, the environmental protection that product yield is high, quantity of three wastes is few
The cyanoacetic acid of cleaning and its preparation method of derivative, the mixed solution of cyanoacetic acid and sodium chloride is separated into by continuous chromatography
Cyanoacetic acid solution and sodium chloride solution, obtain the low cyanoacetic acid solution of chloride ion content or high content of solid cyanoacetic acid product and its
Derivative, it is to avoid the cyanoacetic acid that traditional distillation and concentration separation is caused largely is decomposed, shortcoming that yield is low.
In order to achieve the above objects and other related objects, first aspect present invention provides a kind of cyanoacetic acid preparation method, bag
Include following steps：
(1) cyanogenation：Sodium chloroacetate carries out cyanogenation with Cymag, generates cyanoacetic acid sodium water solution；
(2) acidification reaction：Hydrochloric acid acidifying is added in the cyanoacetic acid sodium water solution obtained toward step (1) and obtains cyanoacetic acid and chlorine
Change the mixed solution of sodium；Or be passed directly into hydrogen chloride gas in the cyanoacetic acid sodium water solution obtained toward step (1) and be acidified, so
Be dissolved in water the solid sodium chloride of precipitation afterwards, obtains the mixed solution of cyanoacetic acid and sodium chloride；
(3) separate：The cyanoacetic acid and the mixed solution of sodium chloride that step (2) is obtained are separated into cyanoacetic acid with continuous chromatography
Solution and sodium chloride solution.
It is concentrated to give as further optimal technical scheme of the invention, in addition to the cyanoacetic acid solution that step (3) is obtained
To cyanoacetic acid solution or solid cyanoacetic acid.The preparation method of the present invention directly carries out continuous chromatography separation, is concentrated again after separation,
Sodium chloride can be avoided, which to separate out heat transfer inequality, causes cyanoacetic acid to decompose.
As optimal technical scheme of the invention further, in step (1), the mol ratio of sodium chloroacetate and Cymag is
1.0:1.0~1.1.
As optimal technical scheme of the invention further, in step (2), the mass concentration of hydrochloric acid is 5~30%, such as 5
~20% or 20~30%；The mol ratio of hydrochloric acid and cyanoacetic acid sodium is 1.0~1.1 times；Hydrogen chloride gas rubs with cyanoacetic acid sodium
You are than being 1.0~1.1 times.
As optimal technical scheme of the invention further, in step (3), the chromatogram that the continuous chromatography separation is used is filled out
Expect the one or more in sodium form, potassium type, ammonium type or calcium type chromatographic isolation resin.
As optimal technical scheme of the invention further, in step (3), the temperature of the continuous chromatography separation for 20~
80 DEG C, such as 20~50 DEG C, 50~60 DEG C, 60~70 DEG C or 70~80 DEG C.
Second aspect of the present invention provides a kind of preparation method of cyanoacetate, comprises the following steps：Using any of the above-described institute
The preparation method for the cyanoacetic acid stated obtains cyanoacetic acid；Esterification, which is carried out, using the cyanoacetic acid obtains cyanoacetate.
Third aspect present invention provides a kind of preparation method of malonate, comprises the following steps：Using any of the above-described institute
The preparation method for the cyanoacetic acid stated obtains cyanoacetic acid；Esterification, which is carried out, using the cyanoacetic acid obtains malonate.
Fourth aspect present invention provides a kind of preparation method of malonic acid, comprises the following steps：Using any of the above-described described
Cyanoacetic acid preparation method obtain cyanoacetic acid；Esterification, which is carried out, using the cyanoacetic acid obtains malonic acid.
The beneficial effects of the present invention are：The present invention is separated the mixed solution of cyanoacetic acid and sodium chloride by continuous chromatography
Into cyanoacetic acid solution and sodium chloride solution, it is to avoid the cyanoacetic acid that traditional distillation and concentration separation is caused largely is decomposed, yield is low
Shortcoming.Simple to operate, production cost of the invention is low, product yield is high, quantity of three wastes is few, is a kind of producer of environment-protecting clean
Method, obtains chloride ion content low cyanoacetic acid solution or high content of solid cyanoacetic acid product and its derivative.
Brief description of the drawings
Fig. 1 is process chart of the invention.
Embodiment
For a further understanding of the present invention, the preferred embodiment of the invention is described with reference to embodiment, still
It should be appreciated that these descriptions are simply to further illustrate the features and advantages of the present invention, rather than to the claims in the present invention
Limitation.
Embodiment 1
Reference picture 1, the invention will be further described：
(1) cyanogenation：By 96.8g monoxones (content 98%, 1.0mol) and 70g water stirring and dissolvings, with 25% carbon
Acid sodium aqueous solution (215g) is neutralized to pH=6.5-7.0, generation sodium chloroacetate 354.8g (content 32.8%)；50 DEG C are warming up to,
Then the sodium cyanide solution 165.0g (1.01mol) of mass concentration 30% is added dropwise, after reaction temperature reaches 85-90 DEG C, stops
Only heat and begin to cool down, when reaction temperature reaches 105 DEG C, reaction terminates, and is cooled to room temperature, obtains cyanoacetic acid sodium water-soluble
Liquid；
(2) acidification reaction：To step (1) obtain cyanoacetic acid sodium water solution add mass concentration 30% hydrochloric acid (127.8g,
1.05mol) acidifying obtains the mixed solution 495.1g of cyanoacetic acid and sodium chloride；
(3) cyanoacetic acid and the mixed solution of sodium chloride obtained step (2) is used filled with ammonium type chromatographic isolation resin
Continuous chromatography piece-rate system is separated at 60 DEG C, respectively obtains cyanoacetic acid solution 412g (cyanoacetic acid content 20.3%, chlorion
Content 0.10%, yield 98.5%) and sodium chloride solution 565.2g (cyanoacetic acid content 0.09%)；
(4) the cyanoacetic acid solution for obtaining step (3) be concentrated to give solid cyanoacetic acid 83.0g (cyanoacetic acid content 98.3%,
96.0%) chloride ion content 0.13%, yield is.
Embodiment 2
(1) cyanogenation：By 96.8g monoxones (content 98%, 1.0mol) and 70g water stirring and dissolvings, with 25% carbon
Acid sodium aqueous solution (215g) is neutralized to pH=6.5-7.0, generation sodium chloroacetate 354.8g (content 32.8%)；50 DEG C are warming up to,
Then the sodium cyanide solution 179.7g (1.1mol) of mass concentration 30% is added dropwise, after reaction temperature reaches 85-90 DEG C, stops
Heat and begin to cool down, when reaction temperature reaches 105 DEG C, reaction terminates, and is cooled to room temperature, obtains cyanoacetic acid sodium water solution；
(2) acidification reaction：To step (1) obtain cyanoacetic acid sodium water solution add mass concentration 5% hydrochloric acid (729.2g,
1.0mol) acidifying obtains the mixed solution 1095.5g of cyanoacetic acid and sodium chloride；
(3) cyanoacetic acid and the mixed solution of sodium chloride obtained step (2) is used filled with ammonium type chromatographic isolation resin
Continuous chromatography piece-rate system is separated at 20 DEG C, respectively obtain cyanoacetic acid solution 884.5g (cyanoacetic acid content 9.53%, chlorine from
Sub- content 0.08%, yield 99.2%) and sodium chloride solution 1131.5g (cyanoacetic acid content 0.02%)；
(4) the cyanoacetic acid solution for obtaining step (4) be concentrated to give solid cyanoacetic acid 83.9g (cyanoacetic acid content 98.1%,
96.8%) chloride ion content 0.35%, yield is.
Embodiment 3
(1) cyanogenation：By 96.8g monoxones (content 98%, 1.0mol) and 70g water stirring and dissolvings, with 25% carbon
Acid sodium aqueous solution (215g) is neutralized to pH=6.5-7.0, generation sodium chloroacetate 354.8g (content 32.8%)；50 DEG C are warming up to,
Then the sodium cyanide solution 171.5g (1.05mol) of mass concentration 30% is added dropwise, after reaction temperature reaches 85-90 DEG C, stops
Only heat and begin to cool down, when reaction temperature reaches 105 DEG C, reaction terminates, and is cooled to room temperature, obtains cyanoacetic acid sodium water-soluble
Liquid；
(2) acidification reaction：To step (1) obtain cyanoacetic acid sodium water solution add mass concentration 20% hydrochloric acid (200.5g,
1.1mol) acidifying obtains the mixed solution 564.8g of cyanoacetic acid and sodium chloride；
(3) cyanoacetic acid and the mixed solution of sodium chloride obtained step (2) is used filled with ammonium type chromatographic isolation resin
Continuous chromatography piece-rate system is separated at 70 DEG C, respectively obtain cyanoacetic acid solution 458.4g (cyanoacetic acid content 18.1%, chlorine from
Sub- content 0.13%, yield 97.5%) and sodium chloride solution 677.5g (cyanoacetic acid content 0.09%).
Embodiment 4
(1) cyanogenation：By 96.8g monoxones (content 98%, 1.0mol) and 70g water stirring and dissolvings, with 25% carbon
Acid sodium aqueous solution (215g) is neutralized to pH=6.5-7.0, generation sodium chloroacetate 354.8g (content 32.8%)；50 DEG C are warming up to,
Then the sodium cyanide solution 165.0g (1.01mol) of mass concentration 30% is added dropwise, after reaction temperature reaches 85-90 DEG C, stops
Only heat and begin to cool down, when reaction temperature reaches 105 DEG C, reaction terminates, and is cooled to room temperature, obtains cyanoacetic acid sodium water-soluble
Liquid；
(2) acidification reaction：Cyanoacetic acid sodium water solution, which is obtained, to step (1) is passed through hydrogen chloride gas (37.2g, 1.02mol)
Acidifying, then adds 133g water (water of addition is used for the solid sodium chloride of solution modeling), obtains the mixed of cyanoacetic acid and sodium chloride
Close solution 538.5g；
(3) cyanoacetic acid and the mixed solution of sodium chloride obtained step (2) is used filled with ammonium type chromatographic isolation resin
Continuous chromatography piece-rate system is separated at 80 DEG C, respectively obtains cyanoacetic acid solution 430g (cyanoacetic acid content 19.1%, chlorion
Content 0.12%, yield 96.6%) and sodium chloride solution 635g (cyanoacetic acid content 0.18%).
Embodiment 5
(1) cyanogenation：By 96.8g monoxones (content 98%, 1.0mol) and 70g water stirring and dissolvings, with 25% carbon
Acid sodium aqueous solution (215g) is neutralized to pH=6.5-7.0, generation sodium chloroacetate 354.8g (content 32.8%)；50 DEG C are warming up to,
Then the sodium cyanide solution 165.0g (1.01mol) of mass concentration 30% is added dropwise, after reaction temperature reaches 85-90 DEG C, stops
Only heat and begin to cool down, when reaction temperature reaches 105 DEG C, reaction terminates, and is cooled to room temperature, obtains cyanoacetic acid sodium water-soluble
Liquid；
(2) acidification reaction：Cyanoacetic acid sodium water solution, which is obtained, to step (1) is passed through hydrogen chloride gas (40.1g, 1.1mol) acid
Change, then add 140g water (water of addition is used for the solid sodium chloride of solution modeling), obtain the mixing of cyanoacetic acid and sodium chloride
Solution 544.5g；
(3) cyanoacetic acid and the mixed solution of sodium chloride obtained step (2) is used filled with ammonium type chromatographic isolation resin
Continuous chromatography piece-rate system is separated at 50 DEG C, respectively obtains cyanoacetic acid solution 436g (cyanoacetic acid content 19.2%, chlorion
Content 0.11%, yield 98.2%) and sodium chloride solution 655g (cyanoacetic acid content 0.15%)；
(4) the cyanoacetic acid solution for obtaining step (4) be concentrated to give solid cyanoacetic acid 82.8g (cyanoacetic acid content 98.5%,
96.0%) chloride ion content 0.38%, yield is.
Comparative example 1
The mixed solution containing 17.1% cyanoacetic acid and 23.2% sodium chloride is made by the step of embodiment 1 (1) and step (2)
500g, control system vacuum is more than -0.09MPa, starts stirring, and less than 90 DEG C progress steaming water of control temperature collect water 210g,
Stop steam water, cool to 80 DEG C, suction filtration, filter cake is washed 10 minutes with 20mL hot-water soaks, solid it is dry sodium chloride 80.7g,
Wash water merges together with filtrate obtains the cyanoacetic acid aqueous solution, and then vacuum distillation concentration steams water 51g again, filters while hot, washs,
Dry sodium chloride 17.6g, filtrate and cleaning solution merge weight 138.6g, cyanoacetic acid content 54.5%, sodium chloride content 8.91%,
Cyanoacetic acid yield 88.9%.
The above-described embodiments merely illustrate the principles and effects of the present invention, not for the limitation present invention.It is any ripe
Know the personage of this technology all can carry out modifications and changes under the spirit and scope without prejudice to the present invention to above-described embodiment.Cause
This, those of ordinary skill in the art is complete without departing from disclosed spirit and institute under technological thought such as
Into all equivalent modifications or change, should by the present invention claim be covered.
Claims (7)
1. a kind of preparation method of cyanoacetic acid, it is characterised in that comprise the following steps：
(1) cyanogenation：Sodium chloroacetate carries out cyanogenation with Cymag, generates cyanoacetic acid sodium water solution；
(2) acidification reaction：Hydrochloric acid acidifying is added in the cyanoacetic acid sodium water solution obtained toward step (1) and obtains cyanoacetic acid and sodium chloride
Mixed solution；Hydrogen chloride gas is passed directly into the cyanoacetic acid sodium water solution obtained toward step (1) to be acidified, and is then added water
The solid sodium chloride of solution modeling, obtains the mixed solution of cyanoacetic acid and sodium chloride；
(3) separate：The cyanoacetic acid and the mixed solution of sodium chloride that step (2) is obtained are separated into cyanoacetic acid solution with continuous chromatography
And sodium chloride solution；
In step (3), the chromatograph packing material that the continuous chromatography separation is used is selected from sodium form, potassium type, ammonium type or calcium type chromatogram point
From the one or more in resin, the temperature of the continuous chromatography separation is 20~80 DEG C.
2. preparation method as claimed in claim 1, it is characterised in that also the cyanoacetic acid solution including step (3) is obtained is dense
Contracting obtains cyanoacetic acid solution or solid cyanoacetic acid.
3. preparation method as claimed in claim 1, it is characterised in that in step (1), the mol ratio of sodium chloroacetate and Cymag
For 1.0:1.0~1.1.
4. preparation method as claimed in claim 1, it is characterised in that in step (2), the mass concentration of hydrochloric acid is 5~30%；
The mol ratio of hydrochloric acid and cyanoacetic acid sodium is 1.0~1.1 times；The mol ratio of hydrogen chloride gas and cyanoacetic acid sodium is 1.0~1.1 times.
5. a kind of preparation method of cyanoacetate, comprises the following steps：Using the cyanoacetic acid as described in any in claim 1-4
Preparation method obtain cyanoacetic acid；Esterification, which is carried out, using the cyanoacetic acid obtains cyanoacetate.
6. a kind of preparation method of malonate, comprises the following steps：Using the cyanoacetic acid as described in any in claim 1-4
Preparation method obtain cyanoacetic acid；Esterification, which is carried out, using the cyanoacetic acid obtains malonate.
7. a kind of preparation method of malonic acid, comprises the following steps：Using the cyanoacetic acid as described in any in claim 1-4
Preparation method obtains cyanoacetic acid；Esterification, which is carried out, using the cyanoacetic acid obtains malonic acid.
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| CN106349108B (en) * | 2016-08-26 | 2018-04-10 | 重庆紫光化工股份有限公司 | A kind of isolation and purification method of cyanoacetic acid |
| CN107793329A (en) * | 2017-10-30 | 2018-03-13 | 烟台国邦化工机械科技有限公司 | A kind of isolation and purification method of cyanoacetic acid |
| CN116730866B (en) * | 2023-08-14 | 2023-10-31 | 山东新和成药业有限公司 | Preparation method of cyanoacetic acid |
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| CN103420834B (en) * | 2013-08-12 | 2015-06-17 | 重庆紫光化工股份有限公司 | Environment-friendly clean method for preparing dimethyl malonate |
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