CN102827013A - Method for continuously producing iminodiacetic acid salt - Google Patents
Method for continuously producing iminodiacetic acid salt Download PDFInfo
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Abstract
The invention provides a method for continuously producing iminodiacetic acid salt. The method has the characteristics of simple process, safety, and high dehydrogenation efficiency and uses a powdered catalyst to synthesize iminodiacetic acid salt by continuously utilizing diethanolamine. The method comprises the following steps of: using diethanolamine as a raw material and carrying out continuous dehydrogenation in a multistage tank type reaction system to obtain the iminodiacetic acid salt. The method has the advantages of simple operation, high safety and high product yield more than or equal to 98%. Moreover, the method can save the time of pretreatment and post-treatment operation and largely increases the production capacity of a device; and meanwhile, a separator is set in each stage of reactor for separating the by-product of hydrogen. The gas is removed at any moment during the reaction process, which is beneficial to the reaction efficiency and the operational safety.
Description
Technical field
The present invention relates to a kind of method of utilizing diethylolamine synthesis of iminodiacetic acid salt continuously.
Background technology
Iminodiethanoic acid (IDA) is widely used in fields such as medicine, agricultural chemicals, rubber, plating, complex compound as a kind of important chemical midbody, as a kind of important intermediate of synthesizing glyphosate, in the application of agricultural chemicals industry, occupies quite great proportion.The compound method of IDA has a lot, comprises that Mono Chloro Acetic Acid glycine method, ammonia are for chloroactic acid method, nitrilotriacetic acid method, NSC 263496 hydrolysis method, diethylolamine dehydriding etc.
At present; IDA method glyphosate production corporate boss will adopt diethanolamine method (DEA process) and NSC 263496 method (IDAN method) to prepare IDA both at home and abroad, and reaction obtains identical midbody Iminodiacetic acid sodium salt salt (DSIDA) to these two kinds of methods with alkaline hydrolysis through dehydrogenation.Wherein, Diethanolamine method process for synthesizing glyphosate route is owing to have the operational path weak point; Device is easy to maximize and serialization; Advantages such as main raw material(s) source is more extensive have been represented the international most advanced level of Glyphosate 62 IPA Salt technical study, and with U.S. Meng Shan all (Monsanto) be that the offshore company of representative also all adopts this technology.The Glyphosate 62 IPA Salt enterprise of domestic this technology of employing is batch production, and comparing than international most advanced level also has certain gap.
CN1563021A discloses a kind of diethylolamine dehydrogenation oxidation method synthesis of iminodiacetic acid salt, and then the technology of synthesizing glyphosate.This method is to utilize intermittently the dehydrogenation still to produce Iminodiacetate, operate comparatively loaded down with trivial detailsly, and reaction produces a large amount of hydrogen early stage needs discharging in time, also will monitor discharging to the hydrogen of generation in the reaction process, has certain danger; Long reaction time in addition, the dehydrogenation yield is not high.
Domestic many patents reach the purpose that reduces the glyphosate production cost, improves the production equipment ability from improving dehydrogenation catalyst performance and life-span.Relate to the method that a kind of diethylolamine dehydrogenation prepares IDA among the CN1398850A, use the skeleton copper of promotors such as adding nickel, molybdenum, cobalt to be catalyzer, solve the low problem that influences plant capacity of catalyst loading.Relate to a kind of supported catalyst preparation methods and applications method that is used for diethylolamine dehydrogenation reaction system iminodiethanoic acid among the CN1827218A; Be applied to the loaded nano-copper nickel composite catalyst of preparation in the diethylolamine dehydrogenation system iminodiacetic acid (salt) acid-respons, show reactive behavior preferably.Use the modified amorphous copper catalyzer to make diethylolamine prepared in reaction iminodiethanoic acid among the CN101134731A, show high reaction activity and stability.
The method that relates to a kind of continuous production iminodiethanoic acid among the CN1148343C; This technology is used the cylindrical, copper catalyzer; The diethylolamine that is mixed with and the mixed liquor of liquid caustic soda injected in the fixed-bed reactor with a kind of cobalt, copper of containing continuously contact with at least a catalyzer that is selected from other metal of cerium, iron, zinc and zirconium and carry out dehydrogenation reaction; 160 ℃ of control reaction temperature, reaction pressure 21.7MPa obtains product Iminodiacetic acid sodium salt salt from reactor bottom.
One piece of patent of the applicant relates to a kind of technology and device that utilizes diethylolamine synthesis of iminodiacetic acid salt continuously, through the improvement realization industrial applications of processing parameter and device.This technology also is to use the copper catalyst of moulding; The diethylolamine of preparation and the mixed liquor of liquid caustic soda are injected in the multistage shell and tube reactor based on the design of isothermal level pressure reaction Kinetics Model continuously; The flow of the service temperature process heating medium of each stage reactor and pressure-controlling are at 100～200 ℃; 1.0～2.5Mpa is regulated and be controlled to the pressure of each stage reactor through tail gas emptying separately respectively, and synthetic liquid enters into the subsequent disposal system from bed through gas-liquid separator.
But; Powder dehydrogenation catalyst improvement in performance in the above-mentioned patent can not fundamentally solve the present domestic problem that intermittence, dehydrogenating technology existed; The main problem one that exists is that dehydrogenation yield level is not high, and the highest yield level of industrialization device is merely 92%, has much room for improvement; The 2nd, the batch technology poor stability, the running time is long, and device capbility can not get performance, differs greatly with the continuous dehydrogenation state of the art.Therefore, do not have the catalyzer of ability production application on the continuous production processes at present, need a kind of production technique that can use fine catalyst to realize the continuous production Iminodiacetate in view of domestic.
Summary of the invention
The objective of the invention is to overcome the deficiency that prior art exists, provide that a kind of technology is simple, safety, dehydrogenation efficient is high, can use fine catalyst to utilize the method for diethylolamine synthesis of iminodiacetic acid salt continuously.
The objective of the invention is that method through a kind of continuous production Iminodiacetate realizes, this method is raw material with the diethylolamine, makes Iminodiacetic acid sodium salt salt through the continuous dehydrogenation reaction.
Said method comprising the steps of: it is 10～30% feed liquid that diethylolamine dissolving back and liquid caustic soda, deionized water uniform mixing are mixed with mass concentration, and feed liquid gets into after mixing kettle mixes in the feed chute, in feed chute, utilizes N
2Protect; Displace dissolved oxygen in the feed liquid; This feed liquid is carried out catalytic dehydrogenating reaction through being metered in the first dehydrogenation still with after the dehydrogenation fine catalyst fully contacts then, and along with the carrying out of reaction, reaction solution enters into the second dehydrogenation still and the 3rd dehydrogenation still in proper order; Service temperature in the dehydrogenation stills at different levels is provided by heating medium, and the working pressure in the still is regulated through exhaust emissions separately.In the 3rd dehydrogenation still, obtain the synthetic liquid of Iminodiacetate after water cooler is cooled to 100～120 ℃, get in the gas-liquid separator and carry out gas-liquid separation, the hydrogen that separated hydrogen gives off in the dehydrogenation still reclaims after treatment; The Iminodiacetate that obtains gets into next stage acidification system and carries out acidification.
Described feed liquid is the mixture of diethylolamine, liquid caustic soda and deionized water, and wherein the mol ratio of diethylolamine and sodium hydroxide is 1: 2.1～2.4.
Described multistage still reaction system is composed in series by 2～5 dehydrogenation reaction stills, and equal independent control temperature of reaction of every stage reactor and reaction pressure, and the respond timely discharge of product hydrogen of every stage reactor guarantee reaction efficiency, also help safety operation.
Detailed Description Of The Invention
The present invention is with diethylolamine, liquid caustic soda, deionized water uniform mixing in proportion, is mixed with mass concentration and is 10～30% feed liquid; In the multistage tank reactor that is made up of the staged reactor series connection, the DEA feed liquid contacts with catalyzer is full and uniform, and under the reaction conditions of selecting, diethylolamine obtains Iminodiacetate through continuous dehydrogenation.
Reaction principle is (main reaction) as follows:
Side reaction:
Described mass concentration is that 10～30% feed liquid is the mixture of diethylolamine, liquid caustic soda, deionized water, and diethylolamine and sodium hydroxide mol ratio are 1: 2.1～2.4; Feeding liquid mixes through mixing kettle earlier, mixes the back and gets in the feed chute, utilizes N in the feed chute
2Protect, displace dissolved oxygen in the feed liquid; Through be metered into multistage tank reactor that preliminary election with nitrogen replacement cross, according to reactor capacity different adjust again by feed rate for feeding liquid.
Described multistage still reaction system is composed in series by 2～5 dehydrogenation reaction stills, and equal independent control temperature of reaction of every stage reactor and reaction pressure, and the respond timely discharge of product hydrogen of every stage reactor guarantee reaction efficiency, also help safety operation.
This multistage still reaction system is based on the design of isothermal level pressure reaction Kinetics Model, and flow or the pressure-controlling of the service temperature of each stage reactor through heating medium is at 100～200 ℃; The pressure of each stage reactor is regulated through tail gas emptying separately respectively and is controlled at 0.6～2.0MPa.Temperature of reaction is owing to consider the existence of side reaction, from the first dehydrogenation still to the end the dehydrogenation still of level appear and successively decrease, in one embodiment; When adopting three grades of dehydrogenation still reactor drums; The first dehydrogenation still temperature of reaction preferably is controlled at 160～175 ℃, and the second dehydrogenation still temperature of reaction preferably is controlled at 150～160 ℃, and the 3rd dehydrogenation still temperature of reaction preferably is controlled at 140～150 ℃; Be reflected in the first dehydrogenation still and carry out fast; Owing to the variation and the carrying out in reaction times of reactant concn, dehydrogenation reaction speed descends in reaction solution gets into the second dehydrogenation still, reduces temperature of reaction this moment; To suppressing the very big effect of playing of side reaction, make the dehydrogenation yield rise to 98% by 92% through such design; Reaction pressure is considered the simple of operation with stable, also can from the first dehydrogenation still to the end the dehydrogenation still of level appear and successively decrease.Every stage reactor pressure is automatically adjusted by the tail gas variable valve, when keeping the stability of system pressure, guarantees that liquid gets into next stage smoothly.
The described synthetic liquid of Iminodiacetate that obtains in the 3rd dehydrogenation still is after water cooler is cooled to 100～120 ℃; Get in the gas-liquid separator and carry out gas-liquid separation, the hydrogen that separated hydrogen gives off in the dehydrogenation still reclaims after treatment and obtains content greater than the hydrogen more than 99.8%; The Iminodiacetate that obtains gets into next stage acidification system and carries out acidification.
Described vent gas treatment comprises washing and dry, and obtains content and reach the purified hydrogen more than 99.8%.
Described tank reactor at different levels need be replaced total system with nitrogen before charging, makes its oxygen level less than 0.1%.
The invention has the advantages that: provide a kind of technological operation simpler, security is higher, the continuous production method of the Iminodiacetate that the industriallization of product yield >=98% is feasible; Save pre-treatment and post-treatment operations time; Improve the throughput of device greatly, every stage reactor all is provided with the separator of by-product hydrogen simultaneously, removes gas in the reaction process at any time; Help reaction efficiency, also help operational safety.
Description of drawings
Fig. 1 is that the structure of multistage tank reactor of the present invention is formed synoptic diagram.
Embodiment
To combine embodiment that detailed explanation is carried out in invention below.
Embodiment 1
With diethylolamine, liquid caustic soda, deionized water uniform mixing in proportion, be mixed with mass concentration and be 25% feed liquid, wherein the mol ratio of diethylolamine and sodium hydroxide is 1: 2.1, feed liquid is utilized N in feed chute
2Protect, displace dissolved oxygen in the feed liquid, this feed liquid gets in the first dehydrogenation still with after the dehydrogenation fine catalyst fully contacts with 30g/min and carries out catalytic dehydrogenating reaction then, and control reaction temperature is 170 ℃, reaction pressure 1.0MPa.Along with the carrying out of reaction, feed liquid gets into the second dehydrogenation still internal reaction in proper order, and control reaction temperature is 155 ℃, reaction pressure 0.9MPa, and the temperature of reaction of the 3rd dehydrogenation still is controlled at 145 ℃, reaction pressure 0.8MPa.In the 3rd dehydrogenation still, obtain the synthetic liquid of Iminodiacetate after water cooler is cooled to 100 ℃, get in the gas-liquid separator and carry out gas-liquid separation, the hydrogen that separated hydrogen gives off in the dehydrogenation still discharges after water seal; The Iminodiacetate that obtains is through analyzing, and the transformation efficiency of diethylolamine is 99.7%, and the yield of Iminodiacetate is 98.2%.
Embodiment 2
With diethylolamine, liquid caustic soda, deionized water uniform mixing in proportion, be mixed with mass concentration and be 25% feed liquid, wherein the mol ratio of diethylolamine and sodium hydroxide is 1: 2.1, feed liquid is utilized N in feed chute
2Protect, displace dissolved oxygen in the feed liquid, this feed liquid gets in the first dehydrogenation still with after the dehydrogenation fine catalyst fully contacts with 30g/min and carries out catalytic dehydrogenating reaction then, and control reaction temperature is 160 ℃, reaction pressure 1.0MPa.Along with the carrying out of reaction, feed liquid gets into the second dehydrogenation still internal reaction in proper order, and control reaction temperature is 150 ℃, reaction pressure 0.9MPa, and the temperature of reaction of the 3rd dehydrogenation still is controlled at 140 ℃, reaction pressure 0.8MPa.In the 3rd dehydrogenation still, obtain the synthetic liquid of Iminodiacetate after water cooler is cooled to 100 ℃, get in the gas-liquid separator and carry out gas-liquid separation, the hydrogen that separated hydrogen gives off in the dehydrogenation still discharges after water seal; The Iminodiacetate that obtains is through analyzing, and the transformation efficiency of diethylolamine is 98.5%, and the yield of Iminodiacetate is 97.6%.
Embodiment 3
With diethylolamine, liquid caustic soda, deionized water uniform mixing in proportion, be mixed with mass concentration and be 25% feed liquid, wherein the mol ratio of diethylolamine and sodium hydroxide is 1: 2.1, feed liquid is utilized N in feed chute
2Protect, displace dissolved oxygen in the feed liquid, this feed liquid gets in the first dehydrogenation still with after the dehydrogenation fine catalyst fully contacts with 30g/min and carries out catalytic dehydrogenating reaction then, and control reaction temperature is 165 ℃, reaction pressure 1.0MPa.Along with the carrying out of reaction, feed liquid gets into the second dehydrogenation still internal reaction in proper order, and control reaction temperature is 160 ℃, reaction pressure 0.9MPa, and the temperature of reaction of the 3rd dehydrogenation still is controlled at 160 ℃, reaction pressure 0.8MPa.In the 3rd dehydrogenation still, obtain the synthetic liquid of Iminodiacetate after water cooler is cooled to 100 ℃, get in the gas-liquid separator and carry out gas-liquid separation, the hydrogen that separated hydrogen gives off in the dehydrogenation still discharges after water seal; The Iminodiacetate that obtains is through analyzing, and the transformation efficiency of diethylolamine is 99.0%, and the yield of Iminodiacetate is 95.4%.
Reference examples
Diethylolamine (99%) 50g, fine catalyst 1g, sodium hydroxide (96%) 41.25g and deionized water 106.8g join in the autoclave, make the reactor drum sealing then, carry out three displacements with nitrogen, drive the air in the reactive system.In the reaction process, stir continuously, control autoclave internal pressure remains on 1.0MPa; Temperature remains on 165 ℃, when the hydrogen that produces to reaction no longer produces, make reaction mass be cooled to 70 ℃ after discharging; Collection material is analyzed, and the yield of Iminodiacetate is 91.8%.
Claims (10)
1. the method for a continuous production Iminodiacetate is characterized in that, with diethylolamine, liquid caustic soda, deionized water uniform mixing in proportion, is mixed with mass concentration and is 10～30% feed liquid; In the multistage tank reactor that is made up of the staged reactor series connection, feed liquid contacts with catalyzer is full and uniform, obtains Iminodiacetate through continuous dehydrogenation.
2. according to the process of claim 1 wherein that described mass concentration is that 10～30% feed liquid is the mixture of diethylolamine, liquid caustic soda, deionized water, diethylolamine and sodium hydroxide mol ratio are 1: 2.1～2.4.
3. according to the process of claim 1 wherein that feeding liquid mixes through mixing kettle earlier, mix the back and get in the feed chute, utilize N in the feed chute
2Protect, displace dissolved oxygen in the feed liquid, through be metered into multistage tank reactor that preliminary election with nitrogen replacement cross, according to reactor capacity different adjust again by feed rate for feeding liquid.
4. according to the process of claim 1 wherein that described multistage still reaction system is composed in series by 2～5 dehydrogenation reaction stills, equal independent control temperature of reaction of every stage reactor and reaction pressure, and the reaction product hydrogen of every stage reactor is in time discharged.
5. according to the method for claim 4; Wherein said multistage still reaction system is based on the design of isothermal level pressure reaction Kinetics Model; Flow or the pressure-controlling of the service temperature of each stage reactor through heating medium is at 100～200 ℃; The pressure of each stage reactor tail gas emptying through is separately respectively regulated and is controlled at 0.6～2.0MPa, temperature of reaction from the first dehydrogenation still to the end the dehydrogenation still of level appear and successively decrease.
6. according to the method for claim 5; Three grades of dehydrogenation still reactor drums of wherein multistage still reaction system's employing; The first dehydrogenation still temperature of reaction is controlled at 160～175 ℃, and the second dehydrogenation still temperature of reaction is controlled at 150～160 ℃, and the 3rd dehydrogenation still temperature of reaction is controlled at 140～150 ℃.
7. method according to claim 1, wherein catalyst system therefor is the dehydrogenation fine catalyst.
8. according to the method for claim 1; Said method comprising the steps of: it is 10～30% feed liquid that diethylolamine dissolving back and liquid caustic soda, deionized water uniform mixing are mixed with mass concentration; Feed liquid gets into after mixing kettle mixes in the feed chute, in feed chute, utilizes N
2Protect; Displace dissolved oxygen in the feed liquid, this feed liquid is carried out catalytic dehydrogenating reaction through being metered in the first dehydrogenation still with after the dehydrogenation fine catalyst fully contacts then, along with the carrying out of reaction; Reaction solution enters into the second dehydrogenation still and the 3rd dehydrogenation still in proper order; Service temperature in the dehydrogenation stills at different levels is provided by heating medium, and the working pressure in the still is regulated through exhaust emissions separately, in the 3rd dehydrogenation still, obtains the synthetic liquid of Iminodiacetate after water cooler is cooled to 100～120 ℃; Get in the gas-liquid separator and carry out gas-liquid separation, the hydrogen that separated hydrogen gives off in the dehydrogenation still reclaims after treatment; The Iminodiacetate that obtains gets into next stage acidification system and carries out acidification.
9. according to the method for claim 7, the hydrogen that wherein said separated hydrogen gives off in the dehydrogenation still reclaims after treatment and obtains content greater than the hydrogen more than 99.8%.
10. according to the described method of above each claim, wherein said tank reactors at different levels need be replaced total system with nitrogen before charging, make its oxygen level less than 0.1%.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114671776A (en) * | 2020-12-24 | 2022-06-28 | 江苏优士化学有限公司 | Continuous synthesis method of iminodiacetic acid alkali metal salt |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1318047A (en) * | 1998-09-14 | 2001-10-17 | 道农业科学公司 | Process for preparing carboxylic acids |
| CN101935288A (en) * | 2009-07-02 | 2011-01-05 | 浙江新安化工集团股份有限公司 | Process and device for synthesizing imino diacetate by using diethanol amine |
| CN102050751A (en) * | 2009-11-05 | 2011-05-11 | 浙江新安化工集团股份有限公司 | Synthesis as well as tail gas treatment technology and device of iminodiacetate |
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2011
- 2011-06-13 CN CN2011101657924A patent/CN102827013A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1318047A (en) * | 1998-09-14 | 2001-10-17 | 道农业科学公司 | Process for preparing carboxylic acids |
| CN101935288A (en) * | 2009-07-02 | 2011-01-05 | 浙江新安化工集团股份有限公司 | Process and device for synthesizing imino diacetate by using diethanol amine |
| CN102050751A (en) * | 2009-11-05 | 2011-05-11 | 浙江新安化工集团股份有限公司 | Synthesis as well as tail gas treatment technology and device of iminodiacetate |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114671776A (en) * | 2020-12-24 | 2022-06-28 | 江苏优士化学有限公司 | Continuous synthesis method of iminodiacetic acid alkali metal salt |
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Application publication date: 20121219 |