CN103288666A - Method for continuous gas phase synthesis of oxamide - Google Patents
Method for continuous gas phase synthesis of oxamide Download PDFInfo
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- CN103288666A CN103288666A CN2013101970937A CN201310197093A CN103288666A CN 103288666 A CN103288666 A CN 103288666A CN 2013101970937 A CN2013101970937 A CN 2013101970937A CN 201310197093 A CN201310197093 A CN 201310197093A CN 103288666 A CN103288666 A CN 103288666A
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Abstract
The invention discloses a method for continuous gas phase synthesis of oxamide. In a gas phase reactor, gas phase oxalic acid dialkyl ester and ammonia gas perform ammonolysis reaction under high temperature to generate oxamide product and corresponding fatty alcohol secondary product, and the oxamide product is collected by a cyclone separator. The method uses the gas phase continuous synthesis technology, and solves the defects of long reaction time and poor capacity of intermittent reaction in the existing oxamide preparation technology; by adopting the method, the reaction time is reduced remarkably, the reaction is continuous and steady, the oxalic ester aminolysis conversion rate is high, the quality of the obtained oxamide is high, and continuous steady industrial production of the oxamide is realized.
Description
Technical field
The present invention relates to a kind of method of synthetic oxamide, particularly the method for the synthetic oxamide of a kind of continuous gas phase belongs to the oxamide preparing technical field.
Background technology
Be a kind of nontoxic and stable colourless crystallization or powder under the oxamide room temperature, as a kind of urea aldehydes slow-release fertilizer with more wide application prospect, its nitrogen content is 31.8%, solubleness in water is 0.016%, nonhygroscopic in air, nontoxic, be easy to store, in hydrolysis or the biological decomposition process, progressively emit ammonia-state nitrogen and carbonic acid gas, satisfied the demand of crop whole growing to nitrogen, reduced the caused loss of leaching loss, volatilization and denitrification of nitrogen, improve chemical fertilizer utilization ratio, reduced fertilizer application frequency, saved manpower and time.Its advantage as slow release fertilizer obtains proof in the agricultural practice abroad, Japanese agriculture technical institute carried out paddy rice and wheat class manurial experiment to oxamide in 1969 to 1970, synthesis measuring and comparative result have been made the evaluation of certainty to the advantage of oxamide nitrogenous fertilizer.West Germany Hoechst AG also carried out field experiment in 1974, proved that oxamide is interim in the crop whole growth, and the suitable needed nutrient of crop can stably be provided, and it is a kind of good slow nitrogenous fertilizer certainly.In addition, oxamide also is used as the stablizer of nitrocotton goods, is used as the reduction of speed agent in propelling agent, is used as to increase the chain viscosity increaser in the lining prescription, is used as foaming agent and cooling agent etc. in gas generator propellant.
The preparation technology of prior art medium-height grass acid amides mainly contains following three kinds:
(1) be feedstock production method (US3989753) with prussic acid (HCN), HCN generates cyanogen (CN) through oxidation earlier
2, make oxamide through hydrolysis again.This method can be divided into Degussa method, phase modulus method, Asahi Chemical Industry's method and Hoechat method, and the difference of four kinds of methods is that oxygenant, catalyzer and technology are different, and this preparation method's shortcoming is that prussic acid toxicity is big, cost is high, and also not seeing has the industrialization report;
(2) pyrolysis method namely adopts ammonium oxalate or oxalic acid urea to carry out pyrolysis and obtains oxamide, but this method cost height does not have practical value, studies less at present.
(3) dialkyl oxalate ammonolysis process (US6348626, US5393319, CN102267921A), this method be dialkyl oxalate under the dissolving of corresponding Fatty Alcohol(C12-C14 and C12-C18) with ammonia generation ammonolysis reaction, generate oxamide and corresponding Fatty Alcohol(C12-C14 and C12-C18), this method is generally gas-liquid phase rhythmic reaction, can't realize the continous-stable operation.
Other preparation method of oxamide, as utilize hafnium complexes directly from nitrogen and carbon monoxide preparation (NatureChemistry, 2, pp.30-35,2010), still be in conceptual phase.
In the production method of above-mentioned listed oxamide, the ammonolysis process of dialkyl oxalate is the comparatively economically viable preparation method of oxamide comparatively speaking, particularly carbon monoxide coupling method synthesizing dimethyl oxalate route is successfully realized suitability for industrialized production in recent years, for the large-scale industrial production of oxamide is laid a good foundation.But above-mentioned dialkyl oxalate ammonolysis process prepares among the preparation technology of oxamide, have that temperature of reaction is low, problem such as long reaction time and reaction can't be carried out continuously, owing to need Fatty Alcohol(C12-C14 and C12-C18) dissolving dialkyl oxalate, so temperature of reaction is generally lower, reaction simultaneously is the gas-liquid reaction that contacts, and the reaction times was generally about 20 hours, and reacts need and carry out in batch reactor, can not move by continous-stable, thereby can't reach industrial production requirement.
Summary of the invention
The objective of the invention is to overcome defective of the prior art, the method for the synthetic oxamide of a kind of continuous gas phase is provided, the synthetic method of described oxamide has reaction continous-stable, short, oxalic acid ester aminolysis transformation efficiency height of reaction times, characteristics such as oxamide quality height.
The present invention is achieved by the following technical programs.
The method of the synthetic oxamide of a kind of continuous gas phase, step is as follows: (1) enters Gas-phase reactor with dialkyl oxalate heater via gasification back from Gas-phase reactor top, liquefied ammonia is entered gas distributor after vaporizer, surge tank gasification, enter Gas-phase reactor by the Gas-phase reactor bottom then, ammonolysis reaction takes place in the two in Gas-phase reactor, ammonia is excessive, and temperature of reaction is that 165-185 ℃, reaction pressure are 1-1.5MPa, residence time 5-30min; (2) part excess of ammonia gas and by-product Fatty Alcohol(C12-C14 and C12-C18) steam are realized separating of gas-solid phase through cyclonic separator with the recycle gas strainer in the powdery oxamide that ammonolysis reaction is generated, the reaction, and the powdery oxamide is collected from whirlwind separator bottom; (3) the isolated part excessive ammonia of institute and by-product Fatty Alcohol(C12-C14 and C12-C18) steam in the step (2) and the part ammonia of discharging through dust filter unit from the Gas-phase reactor top and Fatty Alcohol(C12-C14 and C12-C18) steam are merged pass through the recycle gas water cooler again and cool, and then realize separating of ammonia and liquid phase Fatty Alcohol(C12-C14 and C12-C18) through the gas-liquid separator gas-liquid separation, in the liquid phase Fatty Alcohol(C12-C14 and C12-C18) still residual ammonia and then obtain the Fatty Alcohol(C12-C14 and C12-C18) byproduct through rectification process by adding an amount of alum reaction and generate aluminum hydroxide precipitation and ammonium sulfate is removed; The ammonolysis reaction liberated heat is removed in the process of refrigerated separation ammonia and Fatty Alcohol(C12-C14 and C12-C18) steam; (4) the isolated ammonia of institute in the step (3) is returned to Gas-phase reactor participation reaction with fresh ammonia through circulating air compressor.
The method of the synthetic oxamide of above-mentioned a kind of continuous gas phase, wherein, described dialkyl oxalate is dimethyl oxalate or oxalic acid diethyl ester.
The method of the synthetic oxamide of above-mentioned a kind of continuous gas phase, wherein, described Gas-phase reactor is fluidized-bed reactor, the gas-phase reaction temperature is that 170-185 ℃, reaction pressure are 1.3MPa, residence time 15min.
The method of the synthetic oxamide of above-mentioned a kind of continuous gas phase, wherein, the mol ratio of ammonia and dialkyl oxalate is 2.1-2.5 ︰ 1 in the described ammonolysis reaction.
The method of the synthetic oxamide of above-mentioned a kind of continuous gas phase, wherein, the mol ratio of described alum and ammonia is 1.1-1.5 ︰ 3.
The method of the synthetic oxamide of above-mentioned a kind of continuous gas phase, wherein, the transformation efficiency of described ammonolysis reaction mesoxalic acid dialkyl is greater than 99%, and the purity of oxamide product is greater than 98.5%.
It is as follows that dialkyl oxalate ammonia solution prepares the reaction equation of oxamide:
The method of the synthetic oxamide of a kind of continuous gas phase of the present invention, ammonolysis reaction at high temperature takes place by gas phase dialkyl oxalate and ammonia in Gas-phase reactor, generate oxamide product and corresponding Fatty Alcohol(C12-C14 and C12-C18) byproduct, collect by cyclonic separator and obtain the oxamide product.Present method has significantly shortened the reaction times, reaction continous-stable, oxalic acid ester aminolysis transformation efficiency height, and the oxamide quality height that obtains has been realized the continous-stable suitability for industrialized production of oxamide.
The present invention has following characteristics:
(1) the present invention adopts the continuous synthesis technique of gas phase, has solved long reaction time, production capacity defect of insufficient that present oxamide preparation technology discontinuous reaction exists;
(2) technological reaction temperature of the present invention is higher, and the transformation efficiency height of ammonolysis reaction mesoxalic acid dialkyl can reach more than 99%, and the purity of oxamide product is greater than 98.5%.
(3) technology of the present invention has effectively been removed the remaining ammonia that is dissolved in the Fatty Alcohol(C12-C14 and C12-C18) by the mode that adds an amount of alum and ammonia gas react generation aluminum hydroxide precipitation and ammonium sulfate, eliminate the harm of ammonia dissipation to environment and HUMAN HEALTH generation, be conducive to obtain high-quality Fatty Alcohol(C12-C14 and C12-C18) byproduct simultaneously.
Description of drawings
Fig. 1 is the process flow diagram of the method for the synthetic oxamide of a kind of continuous gas phase of the present invention.
Embodiment
Below by specific embodiment the specific embodiment of the present invention is described in further detail.
Embodiment 1
The method of the synthetic oxamide of a kind of continuous gas phase, step is as follows: (1) enters Gas-phase reactor from Gas-phase reactor top through tangential direction with dimethyl oxalate after steam heater, hotline heater are heated to 170 ℃ of gasifications, liquefied ammonia is entered gas distributor after vaporizer, surge tank gasification, enter Gas-phase reactor by the Gas-phase reactor bottom then, ammonolysis reaction takes place in the two in Gas-phase reactor, the mol ratio of ammonia and dimethyl oxalate is 2.1 ︰ 1, and temperature of reaction is that 165 ℃, reaction pressure are that 1MPa, reaction time are 5min; (2) part excess of ammonia gas and by-product methanol steam are realized separating of gas-solid phase through cyclonic separator with the recycle gas strainer in the powdery oxamide that ammonolysis reaction is generated, the reaction, the powdery oxamide is collected from whirlwind separator bottom, and the purity of liquid-phase chromatographic analysis oxamide product is 98.8%; (3) the isolated part excessive ammonia of institute and by-product methanol steam in the step (2) and the part ammonia of discharging through dust filter unit from the Gas-phase reactor top and methanol steam are merged pass through the recycle gas water cooler again and cool, and then realize separating of ammonia and liquid phase methyl alcohol through the gas-liquid separator gas-liquid separation, in the liquid phase methyl alcohol still residual ammonia by adding the alum reaction and generate aluminum hydroxide precipitation and ammonium sulfate being removed, the mol ratio of alum and ammonia is 1.1 ︰ 3, and then obtains the methyl alcohol byproduct through rectification process; (4) the isolated ammonia of institute in the step (3) is returned to Gas-phase reactor participation reaction with fresh ammonia through circulating air compressor.
Embodiment 2
The method of the synthetic oxamide of a kind of continuous gas phase, step is as follows: (1) enters Gas-phase reactor from Gas-phase reactor top through tangential direction with dimethyl oxalate after steam heater, hotline heater are heated to 170 ℃ of gasifications, liquefied ammonia is entered gas distributor after vaporizer, surge tank gasification, enter Gas-phase reactor by the Gas-phase reactor bottom then, ammonolysis reaction takes place in the two in Gas-phase reactor, the mol ratio of ammonia and dimethyl oxalate is 2.3 ︰ 1, and temperature of reaction is that 175 ℃, reaction pressure are that 1.3MPa, reaction time are 15min; (2) part excess of ammonia gas and by-product methanol steam are realized separating of gas-solid phase through cyclonic separator with the recycle gas strainer in the powdery oxamide that ammonolysis reaction is generated, the reaction, the powdery oxamide is collected from whirlwind separator bottom, and the purity of liquid-phase chromatographic analysis oxamide product is 99.2%; (3) the isolated part excessive ammonia of institute and by-product methanol steam in the step (2) and the part ammonia of discharging through dust filter unit from the Gas-phase reactor top and methanol steam are merged pass through the recycle gas water cooler again and cool, and then realize separating of ammonia and liquid phase methyl alcohol through the gas-liquid separator gas-liquid separation, in the liquid phase methyl alcohol still residual ammonia by adding the alum reaction and generate aluminum hydroxide precipitation and ammonium sulfate being removed, the mol ratio of alum and ammonia is 1.3 ︰ 3, and then obtains the methyl alcohol byproduct through rectification process; (4) the isolated ammonia of institute in the step (3) is returned to Gas-phase reactor participation reaction with fresh ammonia through circulating air compressor.
Embodiment 3
The method of the synthetic oxamide of a kind of continuous gas phase, step is as follows: (1) enters Gas-phase reactor from Gas-phase reactor top through tangential direction with oxalic acid diethyl ester after steam heater, hotline heater are heated to 185 ℃ of gasifications, liquefied ammonia is entered gas distributor after vaporizer, surge tank gasification, enter Gas-phase reactor by the Gas-phase reactor bottom then, ammonolysis reaction takes place in the two in Gas-phase reactor, the mol ratio of ammonia and oxalic acid diethyl ester is 2.5 ︰ 1, and temperature of reaction is that 185 ℃, reaction pressure are that 1.5MPa, reaction time are 30min; (2) part excess of ammonia gas and by-product alcohol vapour are realized separating of gas-solid phase through cyclonic separator with the recycle gas strainer in the powdery oxamide that ammonolysis reaction is generated, the reaction, the powdery oxamide is collected from whirlwind separator bottom, and the purity of liquid-phase chromatographic analysis oxamide product is 99.0%; (3) the isolated part excessive ammonia of institute and by-product alcohol vapour in the step (2) and the part ammonia of discharging through dust filter unit from the Gas-phase reactor top and alcohol vapour are merged pass through the recycle gas water cooler again and cool, and then realize separating of ammonia and liquid phase ethanol through the gas-liquid separator gas-liquid separation, in the liquid phase ethanol still residual ammonia by adding the alum reaction and generate aluminum hydroxide precipitation and ammonium sulfate being removed, the mol ratio of alum and ammonia is 1.5 ︰ 3, and then obtains the ethanol byproduct through rectification process; (4) the isolated ammonia of institute in the step (3) is returned to Gas-phase reactor participation reaction with fresh ammonia through circulating air compressor.
Here description of the invention and application is illustrative, is not to want that therefore, the present invention is not subjected to the restriction of present embodiment with scope restriction of the present invention in the above-described embodiments, and the technical scheme that any employing equivalence replacement obtains is all in the scope of protection of the invention.
Claims (6)
1. the method for the synthetic oxamide of a continuous gas phase, it is characterized in that, step is as follows: (1) enters Gas-phase reactor with dialkyl oxalate heater via gasification back from Gas-phase reactor top, liquefied ammonia is entered gas distributor after vaporizer, surge tank gasification, enter Gas-phase reactor by the Gas-phase reactor bottom then, ammonolysis reaction takes place in the two in Gas-phase reactor, ammonia is excessive, and temperature of reaction is that 165-185 ℃, reaction pressure are 1-1.5MPa, residence time 5-30min; (2) part excess of ammonia gas and by-product Fatty Alcohol(C12-C14 and C12-C18) steam are realized separating of gas-solid phase through cyclonic separator with the recycle gas strainer in the powdery oxamide that ammonolysis reaction is generated, the reaction, and the powdery oxamide is collected from whirlwind separator bottom; (3) the isolated part excessive ammonia of institute and by-product Fatty Alcohol(C12-C14 and C12-C18) steam in the step (2) and the part ammonia of discharging through dust filter unit from the Gas-phase reactor top and Fatty Alcohol(C12-C14 and C12-C18) steam are merged pass through the recycle gas water cooler again and cool, and then realize separating of ammonia and liquid phase Fatty Alcohol(C12-C14 and C12-C18) through the gas-liquid separator gas-liquid separation, in the liquid phase Fatty Alcohol(C12-C14 and C12-C18) still residual ammonia and then obtain the Fatty Alcohol(C12-C14 and C12-C18) byproduct through rectification process by adding an amount of alum reaction and generate aluminum hydroxide precipitation and ammonium sulfate is removed; (4) the isolated ammonia of institute in the step (3) is returned to Gas-phase reactor participation reaction with fresh ammonia through circulating air compressor.
2. the method for the synthetic oxamide of a kind of continuous gas phase as claimed in claim 1 is characterized in that described dialkyl oxalate is dimethyl oxalate or oxalic acid diethyl ester.
3. the method for the synthetic oxamide of a kind of continuous gas phase as claimed in claim 1 is characterized in that described Gas-phase reactor is fluidized-bed reactor, and the gas-phase reaction temperature is that 170-185 ℃, reaction pressure are 1.3MPa, residence time 15min.
4. the method for the synthetic oxamide of a kind of continuous gas phase as claimed in claim 1 is characterized in that the mol ratio of ammonia and dialkyl oxalate is 2.1-2.5 ︰ 1 in the described ammonolysis reaction.
5. the method for the synthetic oxamide of a kind of continuous gas phase as claimed in claim 1 is characterized in that the mol ratio of described alum and ammonia is 1.1-1.5 ︰ 3.
6. the method for the synthetic oxamide of a kind of continuous gas phase as claimed in claim 1 is characterized in that the transformation efficiency of described ammonolysis reaction mesoxalic acid dialkyl is greater than 99%, and the purity of oxamide product is greater than 98.5%.
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105367439A (en) * | 2015-09-07 | 2016-03-02 | 中国科学院福建物质结构研究所 | Process method of co-production of oxamide and carbamic acid ester through ammonia ester exchange method |
| CN106674013A (en) * | 2016-11-29 | 2017-05-17 | 中国科学院福建物质结构研究所 | Technique for co-production of dimethyl carbonate and oxamide |
| CN110862331A (en) * | 2019-12-06 | 2020-03-06 | 东华工程科技股份有限公司 | Method for continuously generating oxamide |
| CN111495312A (en) * | 2020-05-22 | 2020-08-07 | 河南心连心化学工业集团股份有限公司 | Synthetic device and synthetic method for oxamide |
| CN112010783A (en) * | 2019-05-30 | 2020-12-01 | 浙江新和成股份有限公司 | Ammonolysis reaction system, taurine intermediate sodium taurate and preparation method of taurine |
| CN113582869A (en) * | 2021-09-06 | 2021-11-02 | 中国科学院福建物质结构研究所 | Process method for producing oxamide and methyl carbamate in series |
| CN116396179A (en) * | 2023-03-03 | 2023-07-07 | 沈阳化工大学 | Efficient production method of high-purity oxamide under mild condition |
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| US5393319A (en) * | 1992-07-10 | 1995-02-28 | Ube Industries, Ltd. | Process for producing oxamide granules |
| US6348626B1 (en) * | 1991-03-15 | 2002-02-19 | Ube Industries, Ltd. | Process for producing oxamide |
| CN102267921A (en) * | 2011-05-26 | 2011-12-07 | 陈贻盾 | Continuous processing technology for synthesis of oxamide |
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| US6348626B1 (en) * | 1991-03-15 | 2002-02-19 | Ube Industries, Ltd. | Process for producing oxamide |
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105367439A (en) * | 2015-09-07 | 2016-03-02 | 中国科学院福建物质结构研究所 | Process method of co-production of oxamide and carbamic acid ester through ammonia ester exchange method |
| CN106674013A (en) * | 2016-11-29 | 2017-05-17 | 中国科学院福建物质结构研究所 | Technique for co-production of dimethyl carbonate and oxamide |
| CN106674013B (en) * | 2016-11-29 | 2019-06-18 | 中国科学院福建物质结构研究所 | A kind of process of co-producing dimethyl carbonate and oxamides |
| CN112010783A (en) * | 2019-05-30 | 2020-12-01 | 浙江新和成股份有限公司 | Ammonolysis reaction system, taurine intermediate sodium taurate and preparation method of taurine |
| WO2020238943A1 (en) * | 2019-05-30 | 2020-12-03 | 浙江新和成药业有限公司 | Ammonolysis reaction system, and preparation methods for taurine intermediate taurine sodium and taurine |
| CN112010783B (en) * | 2019-05-30 | 2024-01-30 | 浙江新和成股份有限公司 | Ammonolysis reaction system, taurine intermediate sodium taurate and preparation method of taurine |
| CN110862331A (en) * | 2019-12-06 | 2020-03-06 | 东华工程科技股份有限公司 | Method for continuously generating oxamide |
| CN110862331B (en) * | 2019-12-06 | 2021-05-11 | 东华工程科技股份有限公司 | Method for continuously generating oxamide |
| CN111495312A (en) * | 2020-05-22 | 2020-08-07 | 河南心连心化学工业集团股份有限公司 | Synthetic device and synthetic method for oxamide |
| CN113582869A (en) * | 2021-09-06 | 2021-11-02 | 中国科学院福建物质结构研究所 | Process method for producing oxamide and methyl carbamate in series |
| CN116396179A (en) * | 2023-03-03 | 2023-07-07 | 沈阳化工大学 | Efficient production method of high-purity oxamide under mild condition |
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