CN105367439A - Process method of co-production of oxamide and carbamic acid ester through ammonia ester exchange method - Google Patents
Process method of co-production of oxamide and carbamic acid ester through ammonia ester exchange method Download PDFInfo
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Abstract
The invention discloses a process method of co-production of oxamide and carbamic acid ester through an ammonia ester exchange method. According to the process method, urea and oxalic acid diethyl serve as raw materials, and two products, namely the oxamide and the carbamic acid ester, can be obtained at the same time through a series of ammonia ester exchange reactions. By means of the process, the problems that products are singular, and by-products affect the reaction process in an original technology for synthesizing oxamide through oxalic acid diethyl ammonolysis and a technology for synthesizing carbamic acid ester through urea alcoholysis are solved; besides, due to the fact that urea is obtained through CO<2> and NH<3> synthesis, NH<3> is replaced with urea, and the process method has active significance in converting CO<2> into high added-value chemicals and efficiently utilizing CO<2>.
Description
Technical field
The invention belongs to oxamide synthetic technology and carbamate synthesis technical field, relate to the technique of ester ammonia exchange process coproduction oxamide that a kind of oxalate diester and urea participates in jointly and carbamate.
Background technology
Oxamide is a kind of urea aldehydes slow release fertilizer, nontoxic and be easy to store, nitrogen content is 31.8%, and the solubleness in water is 0.016%, decomposes gradually and discharge ammonia-state nitrogen and carbonic acid gas in biodegradable process.Oxamide has the feature of not easily leaching loss, not only increases chemical fertilizer utilization ratio, decreases fertilizer application frequency, also avoid the pollution to water resources.The feature of its progressively slowly-releasing meets the growth rhythm of crop, and disposable using in a large number can not burn out crop or excessive consumption causes crop hyperplasia, meets the crop whole growth stage to the demand of nitrogenous fertilizer.Compare with readily avaiable fertilizer such as urea, oxamide reduces chemical fertilizer, manpower and time cost in agricultural production process as slow release fertilizer, is confirmed in this agricultural practice at home and abroad.
At present, oxamide synthetic technology mainly contains following three kinds:
(1) synthesize oxamide through HCN, this method is divided into again single stage method and two step method.Single stage method, also known as Hoechst method, uses O
2containing CuNO
3dilute acetic acid solution in directly HCN is oxidized to oxamide; Two step method is such as described in US Patent No. 3989753, HCN first oxidized generation (CN)
2, (CN)
2hydrolysis generates oxamide again.Two step method is divided into again Degussa method, phase modulus method and Asahi Chemical Industry's method, and difference is mainly that used oxygenant is different.The defect of the method is that the toxicity of HCN is large, and cost is high.
(2) pyrolysis method, obtains a small amount of oxamide with ammonium oxalate or oxalic acid urea pyrolysis.This method shortcoming is not have use value and cost is high, and research is less at present.
(3) through oxalate diester ammonolysis process, by CO coupling synthesis of oxalic acid diester, then ammonia solution obtains oxamide.Company of Ube Industries Ltd. in 1981 takes the lead in building up annual output 600 tons of factories through oxalate diester ammonolysis synthesis oxamide.US Patent No. 6348626 makes public for the first time the research by oxalate diester ammonolysis synthesis oxamide, take oxalate diester as raw material, with the fatty alcohol of correspondence for solvent, synthesizes purity and the yield of oxamide under discussing differential responses condition.
In recent years, CO through nitrous acid ester coupling synthesis of oxalic acid diester technique gradual perfection and successfully realize industrialization, for oxalate diester ammonolysis process synthesis oxamide scale operation lay a good foundation.Chinese patent CN102267921 for basic raw material, proposes a kind of continuous processing synthesizing oxamide with coal, water and air.Coal through water-gas shift preparing synthetic gas, then obtains CO and H through pressure-variable adsorption or low temperature separation process
2, air is separated through pressure-variable adsorption and obtains N
2.Wherein CO is through nitrous acid ester coupling synthesis of oxalic acid diester, N
2and H
2for the synthesis of NH
3, oxalate diester is finally by NH
3ammonia solution obtains oxamide.Chinese patent CN103288666A describes a kind of method of continuous vapor-phase synthesis oxamide, adopts fluidized-bed reactor to instead of the continuous seepage that original batch reactor achieves oxamide.US Patent No. 5393319 and Chinese patent CN103242188A are also studied the problem that oxamide controls grain forming in building-up process.But although possess the advantages such as low toxicity low cost through the technique of oxalate diester ammonolysis synthesis oxamide, this route still exists many defects, such as: product is comparatively single, a kind of valuable chemical of oxamide can only be obtained; The content of the by product fatty alcohol that reaction generates must control below certain proportion, otherwise the transformation efficiency of oxalate diester can be greatly affected, and therefore carrying out byproduct in process thing fatty alcohol in reaction needs constantly to be removed; Because NH in ammonia solution preocess
3utilization ratio low, reaction process needs to pass into excessive NH
3, these have little time the NH reacted away
3can not directly be discharged in air, therefore need to absorb or cycling and reutilization.Such as, in the technique of Chinese patent 103242188A and Chinese patent CN103288666A all additional designs NH
3absorption system, condenser system and the recycle system, and the kettle of reaction unit, gas circuit, NH
3the recycle system and the necessary resistance to ammonia corrosion of absorption system, bring the increase of equipment and process cost thus.
Carbamate is a kind of important fine chemicals, be commonly used for organic synthesis intermediate, for the synthesis of important chemical such as weedicide, sterilant, antiphlogistic, tranquilizer, rubber antioxidants, thermo-stabilizer, cement additires, there is important using value in agricultural, medicine and the field such as industrial.Carbamate chemicals for agriculture, its poisoning specificity is strong, easily degraded, residual low, to the mankind and mammalian toxicity little, in countries in the world, development is very fast.In addition, some carbamate and derivative thereof also have a wide range of applications in resin modified, textile finishing, powder coating etc.
At present, carbamate synthetic technology mainly contains following three kinds:
(1) phosgenation, traditional synthetic method mainly with hypertoxic phosgene for raw material, obtain Urethylane through alcoholysis and ammonia solution.This production technique operation is many, device is complicated, produce the hydrochloric acid of severe corrosive in production process, this requires higher to the sealing of production equipment and corrosion resistance nature, cause equipment cost to increase, and phosgene has severe toxicity, adopt non-phosgene to produce Urethylane imperative.
(2) urea nitrate salt method, though avoid using phosgene, this method reactions steps is many, and nitrous acid urea salt explosive, industrial production casualty ratio of accidents is high, and nitrous acid easily produces nitrogen with amino acting on, and affects productive rate, so far can not suitability for industrialized production.
(3) alcoholysis of urea, with urea and fatty alcohol for raw material, by alcoholysis reaction synthesis of carbamates.It is simple that this method has technique, and the features such as environmental friendliness, realize suitability for industrialized production at present.
Although alcoholysis of urea has a extensive future, also there is many problems needing solution badly, comprising: the problem that product is single; The recycle problem of excess fat alcohol; The most important thing is discharge a large amount of NH in alcoholysis reaction process
3, and NH
3existence alcoholysis reaction can be suppressed to carry out to forward, thus affect the yield of carbamate, so NH
3shift out in time and follow-up absorption or discharge are the keys of restriction this method industry law, such as, all relate to NH in Chinese patent CN103254101A and Chinese patent CN1693302A
3shift out technique and shift out the design problem of system, and want head it off certainly will cause the increase of equipment and process cost.
Summary of the invention
The object of this invention is to provide the technique of ester ammonia exchange process coproduction oxamide that a kind of oxalate diester and urea participates in jointly and carbamate.This technique uses urea to replace NH
3participate in the ammonolysis reaction of oxalate diester, the amino on urea and the ester group on oxalate diester exchange, and obtain final product oxamide and carbamate.This technique is intended to solve that product in oxalate diester ammonolysis synthesis oxamide technology and urea alcoholysis synthesis of carbamates technology is single, by product affects the problems such as reaction process.In addition, because urea is through CO
2and NH
3synthesis obtains, and this technique urea replaces NH
3, to CO
2the efficiency utilization changing into high added value value chemical has positive effect.
The technique of ester ammonia exchange process coproduction oxamide provided by the present invention and carbamate is with urea, oxalate diester for raw material, by a series of ester ammonia permutoid reaction coproduction oxamide and carbamate,
Reaction equation is as follows:
In reaction formula, one of R alkyl representing C1 ~ C4, is more preferably one of the alkyl of C1, C2;
R in fatty alcohol (ROH) is consistent with the R in oxalate diester, is one of the alkyl of C1 ~ C4, one of alkyl being more preferably C1, C2;
Concrete technology step is: with urea and oxalate diester for raw material, with the fatty alcohol in oxalate diester corresponding to alkoxyl group for solvent, add in proportion in reactor, pass into N
2displace the air in still and be pressurized to 0.1 ~ 5MPa, stir until raw material mixes at 50 ~ 80 DEG C of temperature, stirring reaction 5 ~ 20h at 80 ~ 250 DEG C of temperature, adopt the mixture be obtained by reacting the separation means such as distillation, filtration, condensation, extraction to be separated, obtain product oxamide and carbamate respectively;
Described oxalate diester any one oxalate diester that to be ester group carbonatoms be in 1-4; Be preferably dimethyl oxalate or oxalic acid diethyl ester;
Described fatty alcohol any one fatty alcohol that to be carbonatoms be in 1-4; Be preferably methyl alcohol or ethanol;
Wherein the mol ratio of urea and oxalate diester is 1 ~ 10:1, and the mol ratio of fatty alcohol and oxalate diester is 2 ~ 40:1;
Wherein preferably reaction pressure is 0.1 ~ 2MPa; Preferably temperature of reaction is 100 ~ 150 DEG C.
The present invention with oxalate diester be the once through yield scope of criterion calculation oxamide 48 ~ 100%, be that the yield spectra of criterion calculation carbamate is 60 ~ 100% with urea.
Infrared spectra detection is carried out to products therefrom, the results are shown in Figure 1, Fig. 2, as seen from the figure, the infrared signature peak of product oxamide and carbamate is substantially identical with the standard model bought, and illustrates that the product be obtained by reacting meets expection.
Beneficial effect of the present invention:
(1) coproduction obtains oxamide and carbamate, solve the problem that in existing oxalate diester ammonolysis process synthesis oxamide technique and urea alcoholysis synthesis of carbamates technique, product is single, wherein carbamate can also obtain important large chemicals carbonic ether through further alcoholysis reaction;
(2) NH is replaced with urea
3, do not need to consider to drop into excess raw material NH
3recovery and recycle problem;
(3) amino of the ester group and urea that react mesoxalic acid diester directly exchanges, fatty alcohol can not be produced, the conversion of oxalate diester is not suppressed, do not need the problem considering that in existing oxalate diester ammonolysis process synthesis oxamide technique, by product fatty alcohol shifts out in time, avoid the increase of the technology and equipment cost brought thus;
(4) in reaction, the amino of urea and oxalate diester generate insoluble oxamide and precipitate and leave homogeneous reaction system, so can not produce NH
3, the conversion of urea is not suppressed, does not need to consider by product NH in existing urea alcoholysis synthesis of carbamates technique
3the problem shifted out in time, avoids the increase of the technology and equipment cost brought thus.
Figure of description
Fig. 1 is the infrared spectrogram of oxamide: wherein (a) is oxamide standard model, the oxamide sample that (b) obtains for embodiment 1.Fig. 2 is the infrared spectrogram of Urethylane: wherein (a) is Urethylane standard model; B sample that () obtains for embodiment 1.
Embodiment
Embodiment 1:
Take 10g dimethyl oxalate respectively, 10g urea and 10g methyl alcohol are packed into closed pressure resistant and in the 100ml reaction vessel of subsidiary heating and stirring device, in reactor, pass into N
2displace the air in still, displacement 3 times, finally passes into N continuously
2be pressurized to 0.5MPa, design temperature is 70 DEG C, makes raw material dissolve completely and mix under stirring heating.Setting temperature of reaction is 150 DEG C, and setting stirring velocity is 100rpm, and reaction carries out 12h continuously, and question response temperature in the kettle is down to room temperature.Open tail gas emptying needle-valve, reacting kettle inner pressure is reduced to 0.1MPa.Open reactor, reacted mixture is taken out, be placed in the flask of Rotary Evaporators.Setting vacuum tightness is 3mmHg, and temperature is 80 DEG C, and speed of rotation is 100rpm, underpressure distillation 5h, and collecting and obtain Urethylane 8.5g, is that the once through yield of criterion calculation Urethylane is 68% with urea.Collect remaining white powder in flask, cleaning in hot methanol solution, obtain pure oxamide 5g after drying, is that the once through yield of criterion calculation oxamide is 67.1% with dimethyl oxalate.In table 1
Embodiment 2:
With the embodiment of embodiment 1, difference is that reaction pressure is 0.7MPa, and the add-on of methyl alcohol is 20g.Product analyses is in table 1
Embodiment 3:
With the embodiment of embodiment 1, difference is that reaction pressure is 0.7MPa, and the add-on of methyl alcohol is 30g.Product analyses is in table 1
Embodiment 4:
With the embodiment of embodiment 1, difference is that reaction pressure is 2.2MPa, and temperature of reaction is 170 DEG C, and the add-on of methyl alcohol is 50g.Product analyses is in table 1
Embodiment 5:
With the embodiment of embodiment 1, difference is that reaction pressure is 4.5MPa, and temperature of reaction is 180 DEG C, and the add-on of methyl alcohol is 100g.Product analyses is in table 1
Embodiment 6:
With the embodiment of embodiment 1, difference is that reaction pressure is 0.3MPa, and temperature of reaction is 145 DEG C, and the add-on of urea is 15g.Product analyses is in table 1
Embodiment 7:
With the embodiment of embodiment 1, difference is that reaction pressure is 0.3MPa, and temperature of reaction is 140 DEG C, and the add-on of urea is 20g.Product analyses is in table 1
Embodiment 8:
Take 12.4g oxalic acid diethyl ester respectively, 10g urea and 14.4g ethanol are packed into closed pressure resistant and attach in the 100ml reaction vessel of heating and stirring device.N is passed in reactor
2displace the air in still, displacement 3 times, finally passes into N continuously
2be pressurized to 0.5MPa, design temperature is 30 DEG C, makes raw material dissolve completely and mix under stirring heating.Setting temperature of reaction is 120 DEG C, and setting stirring velocity is 100rpm, and reaction carries out 6h continuously, and then stop heating and stir, question response temperature in the kettle is down to room temperature.Open tail gas emptying needle-valve, reacting kettle inner pressure is reduced to 0.1MPa.Open reactor, reacted mixture is taken out, be placed in the flask of Rotary Evaporators.Setting vacuum tightness is 3mmHg, and temperature is 83 DEG C, and speed of rotation is 100rpm, underpressure distillation 5h, collects and obtains urethanum 14.5g, is that the once through yield of raw material calculating urethanum is 97.8% with urea.Collecting remaining white powder in flask, clean, obtain pure oxamide product 3.9g after drying in hot ethanol solution, is that the once through yield of raw material calculating oxamide is 52.3% with oxalic acid diethyl ester.
Table 1
| Oxamide (g) | Carbamate (g) | Oxamide once through yield (%) | Carbamate once through yield (%) | |
| Embodiment 1 | 5 | 8.5 | 67.1 | 68 |
| Embodiment 2 | 7.4 | 9.7 | 99.2 | 77.6 |
| Embodiment 3 | 7.2 | 10.1 | 96.5 | 80.8 |
| Embodiment 4 | 4 | 12.2 | 53.6 | 97.6 |
| Embodiment 5 | 3.6 | 12.2 | 48.3 | 97.6 |
| Embodiment 6 | 6.7 | 11.4 | 89.8 | 60.8 |
| Embodiment 7 | 7.3 | 12.4 | 97.9 | 49.6 |
| Embodiment 8 | 3.9 | 14.5 | 52.3 | 97.8 |
Claims (2)
1. a processing method for ester ammonia exchange process coproduction oxamide and carbamate, concrete technology step is: with urea and oxalate diester for raw material, with the fatty alcohol in oxalate diester corresponding to alkoxyl group for solvent, add in proportion in reactor, pass into N
2displace the air in still and be pressurized to 0.1 ~ 5MPa, stir until raw material mixes at 50 ~ 80 DEG C of temperature, stirring reaction 5 ~ 20h at 80 ~ 250 DEG C of temperature, adopt the mixture be obtained by reacting the separation means such as distillation, filtration, condensation, extraction to be separated, obtain product oxamide and carbamate respectively;
Any one oxalate diester of described oxalate diester to be ester group carbonatoms be 1-4; Described fatty alcohol any one fatty alcohol that to be carbonatoms be in 1-4;
The additional proportion of described raw material is: the mol ratio of urea and oxalate diester is 1 ~ 10:1, and the mol ratio of fatty alcohol and oxalate diester is 2 ~ 40:1.
2. the processing method of ester ammonia exchange process coproduction oxamide according to claim 1 and carbamate, is characterized in that described oxalate diester is dimethyl oxalate or oxalic acid diethyl ester; Described fatty alcohol is methyl alcohol or ethanol; Described reaction pressure is 0.1 ~ 2MPa; Temperature of reaction is 100 ~ 150 DEG C.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| 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 |
| CN112915993A (en) * | 2021-01-22 | 2021-06-08 | 中国科学院福建物质结构研究所 | Catalyst for coproduction of oxamide and methyl carbamate and preparation method thereof |
| 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 |
| CN116237061A (en) * | 2022-12-19 | 2023-06-09 | 中国科学院福建物质结构研究所 | Method for recovering catalyst of co-production reaction of oxamide and methyl carbamate |
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| US20050027120A1 (en) * | 2003-06-02 | 2005-02-03 | Reactimex, S.A. De C.V. | Method for the synthesis of amides and related products from esters or ester-like compounds |
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2015
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| 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 |
| CN112915993A (en) * | 2021-01-22 | 2021-06-08 | 中国科学院福建物质结构研究所 | Catalyst for coproduction of oxamide and methyl carbamate and preparation method thereof |
| 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 |
| CN116237061A (en) * | 2022-12-19 | 2023-06-09 | 中国科学院福建物质结构研究所 | Method for recovering catalyst of co-production reaction of oxamide and methyl carbamate |
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