CN116375605B - Continuous N-formylurea production process - Google Patents
Continuous N-formylurea production process Download PDFInfo
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- CN116375605B CN116375605B CN202310174858.9A CN202310174858A CN116375605B CN 116375605 B CN116375605 B CN 116375605B CN 202310174858 A CN202310174858 A CN 202310174858A CN 116375605 B CN116375605 B CN 116375605B
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- CN
- China
- Prior art keywords
- formylurea
- reaction kettle
- urea
- production process
- formic acid
- Prior art date
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- JOWMUPQBELRFRZ-UHFFFAOYSA-N n-carbamoylformamide Chemical compound NC(=O)NC=O JOWMUPQBELRFRZ-UHFFFAOYSA-N 0.000 title claims abstract description 18
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 9
- BDAGIHXWWSANSR-UHFFFAOYSA-N methanoic acid Natural products OC=O BDAGIHXWWSANSR-UHFFFAOYSA-N 0.000 claims abstract description 50
- 238000006243 chemical reaction Methods 0.000 claims abstract description 33
- 239000000463 material Substances 0.000 claims abstract description 29
- OSWFIVFLDKOXQC-UHFFFAOYSA-N 4-(3-methoxyphenyl)aniline Chemical compound COC1=CC=CC(C=2C=CC(N)=CC=2)=C1 OSWFIVFLDKOXQC-UHFFFAOYSA-N 0.000 claims abstract description 25
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 claims abstract description 25
- 239000004202 carbamide Substances 0.000 claims abstract description 25
- 235000019253 formic acid Nutrition 0.000 claims abstract description 25
- 239000003054 catalyst Substances 0.000 claims abstract description 18
- 238000000034 method Methods 0.000 claims abstract description 12
- 238000001704 evaporation Methods 0.000 claims abstract description 9
- 230000008020 evaporation Effects 0.000 claims abstract description 9
- 238000010924 continuous production Methods 0.000 claims abstract description 5
- 238000003756 stirring Methods 0.000 claims abstract description 5
- 239000013078 crystal Substances 0.000 claims abstract description 4
- 238000010438 heat treatment Methods 0.000 claims abstract description 3
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 claims description 8
- 239000000292 calcium oxide Substances 0.000 claims description 8
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 claims description 8
- 230000000694 effects Effects 0.000 claims description 6
- 230000014759 maintenance of location Effects 0.000 claims description 6
- OSGAYBCDTDRGGQ-UHFFFAOYSA-L calcium sulfate Chemical compound [Ca+2].[O-]S([O-])(=O)=O OSGAYBCDTDRGGQ-UHFFFAOYSA-L 0.000 claims description 4
- 239000000203 mixture Substances 0.000 claims description 2
- 238000002360 preparation method Methods 0.000 abstract description 5
- 239000003337 fertilizer Substances 0.000 abstract description 4
- 238000003889 chemical engineering Methods 0.000 abstract description 2
- 239000012847 fine chemical Substances 0.000 abstract description 2
- 238000003860 storage Methods 0.000 description 18
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 8
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 6
- 238000005469 granulation Methods 0.000 description 5
- 230000003179 granulation Effects 0.000 description 5
- 239000002245 particle Substances 0.000 description 5
- XGEGHDBEHXKFPX-UHFFFAOYSA-N N-methyl urea Chemical compound CNC(N)=O XGEGHDBEHXKFPX-UHFFFAOYSA-N 0.000 description 4
- 229910000019 calcium carbonate Inorganic materials 0.000 description 4
- 239000012535 impurity Substances 0.000 description 4
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 238000005054 agglomeration Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 239000003674 animal food additive Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 239000003112 inhibitor Substances 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 235000016709 nutrition Nutrition 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 102000004169 proteins and genes Human genes 0.000 description 1
- 108090000623 proteins and genes Proteins 0.000 description 1
- 239000013049 sediment Substances 0.000 description 1
- 238000004062 sedimentation Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C273/00—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups
- C07C273/18—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups of substituted ureas
- C07C273/1854—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups of substituted ureas by reactions not involving the formation of the N-C(O)-N- moiety
- C07C273/1863—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups of substituted ureas by reactions not involving the formation of the N-C(O)-N- moiety from urea
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C273/00—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups
- C07C273/18—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups of substituted ureas
- C07C273/189—Purification, separation, stabilisation, use of additives
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/584—Recycling of catalysts
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention relates to the technical field of fine chemical engineering, in particular to a production process of continuous N-formylurea. The production process is realized by the following steps: respectively conveying formic acid and urea into a reaction kettle; adding a catalyst into a reaction kettle; heating and stirring the mixed material in a reaction kettle for reacting for a period of time, separating out N-formylurea crystals, performing triple-effect evaporation treatment, and extruding and granulating. The production process is a continuous production process, no caking is generated in the preparation process, special stirring and crushing equipment is not needed, and the process is easy to control; the added catalyst does not need additional post-treatment, can be directly used as a fertilizer component, and greatly saves the treatment cost; the purity of the N-formylurea prepared by the method is 95-98%, and the purity is high.
Description
Technical Field
The invention relates to the technical field of fine chemical engineering, in particular to a production process of continuous N-formylurea.
Background
N-formic acid urea, N-formylurea and formylurea with the molecular formula of C2H4N2O2, white crystal powder with the melting point of 170-173 ℃ and the density of 1.286g/cm < 3 >, can be used as a nutritional feed additive or a corrosion inhibitor of a fertilizer due to the fact that the N-formic acid urea contains non-protein nitrogen, and reduces the use amount of the fertilizer.
At present, in the preparation process of N-formylurea, formic acid and urea are mostly adopted to be mixed, water is separated by a rectifying device, concentrated phosphoric acid and the like are added as catalysts, and finally, the products are obtained through drying and crushing. On the one hand, concentrated phosphoric acid and the like are adopted as catalysts, products obtained by subsequent preparation need to be further processed, on the other hand, in the reaction process, a specific kneader or a powerful stirrer and other crushing devices are needed because of easy agglomeration, and the reaction process is not easy to control.
Disclosure of Invention
In order to solve the defects of the prior art, the invention aims to provide a continuous production process of N-formylurea, which is simple, low in energy consumption and suitable for the production of N-formylurea.
In order to achieve the above purpose, the technical scheme of the invention is as follows:
The invention provides a continuous production process of N-formylurea, which comprises the following steps:
S1: respectively conveying formic acid and urea into a reaction kettle;
S2: adding a catalyst into a reaction kettle;
S3: heating and stirring the mixed material in a reaction kettle for reacting for a period of time, separating out N-formylurea crystals, performing triple-effect evaporation treatment, and extruding and granulating.
Further, in step S1, the molar ratio of urea to formic acid is 1:1-1.5.
Further, in the step S2, the addition amount of the catalyst is 1-5 per mill of the total mixture of formic acid and urea. The catalyst used in the invention is one or two of calcium sulfate and calcium oxide.
Further, in the step S3, the reaction is carried out for 0.5-3 hours at 30-95 ℃ under normal pressure.
Further, in step S4, the three-way evaporation specifically includes: the temperature of the material in the first-effect evaporator is 110-120 ℃, the pressure is normal pressure, and the retention time is 5-60min; the temperature of the material in the two-effect evaporator is 100-105 ℃, the pressure is-5 Pa to-10 Pa, and the retention time is 10-55min; the temperature of the material in the triple effect evaporator is 90-95 ℃, the pressure is-0.01 to-0.05 MPa, and the retention time is 10-50min.
In the preparation process of the invention, the catalyst is added after the formic acid and the urea are fully added and fully mixed.
The beneficial effects of the invention are as follows:
(1) The production process is a continuous production process, no caking is generated in the preparation process, special stirring and crushing equipment is not needed, and the process is easy to control;
(2) The added catalyst does not need additional post-treatment, can be directly used as a fertilizer component, and greatly saves the treatment cost;
(3) The purity of the N-formylurea prepared by the method is 95-98%, and the purity is high.
Drawings
FIG. 1 is a schematic and schematic illustration of the process flow of the present invention; wherein, 1 is urea storage tank, 2 is formic acid storage tank, 3 is catalyst storage tank, 4 is reation kettle, 5 is centrifugal pump, 6 is the buffer tank, 7 is one effect evaporimeter, 8 is two effect evaporimeters, 9 is three effect evaporimeters, 10 is the extruder, 11 is the product tank, 12 is the condenser.
Detailed Description
The technical scheme of the invention is further explained and illustrated by specific examples.
Example 1
10Kg of urea particles and 7.66Kg of formic acid (99%) are respectively pumped into a reaction kettle 4 from a urea storage tank 1 and a formic acid storage tank 2, stirred for 0.5h and uniformly mixed, 18.5g of calcium oxide is pumped into the reaction kettle 4 from a catalyst storage tank 3, urea, formic acid and calcium oxide fully react for 2h at the reaction temperature of 95 ℃, a part of reacted materials are conveyed into a buffer tank 6 through a centrifugal pump 5, a part of the materials flow back to the reaction kettle 4, the reacted materials sequentially enter a first-effect evaporator 7, a second-effect evaporator 8 and a third-effect evaporator 9 from the buffer tank 6, the temperature in the first-effect evaporator is 108 ℃, the pressure is normal pressure, the treatment time is 10min, the temperature in the second-effect evaporator is 103 ℃, the pressure is-6 Pa, the treatment time is 20min, the third-effect evaporator temperature is 92 ℃, the pressure is-0.03 Mpa, the treatment time is 30min, the materials are directly fed into an extruder 10 for granulation after impurities are removed through three-effect evaporation treatment, and then fed into a product tank 11, and the purity of N-methyl urea product is 95%.
Example 2
15Kg of urea particles and 12.65Kg of formic acid (99%) are respectively pumped into a reaction kettle 4 from a urea storage tank 1 and a formic acid storage tank 2, stirred for 1h and uniformly mixed, 52.46g of calcium carbonate is pumped into the reaction kettle 4 from a catalyst storage tank 3, urea, formic acid and calcium carbonate fully react for 3h, the reaction temperature is 88 ℃, a part of the reacted materials are conveyed into a buffer tank 6 through a centrifugal pump 5, a part of the reacted materials are refluxed into the reaction kettle 4, the reacted materials sequentially enter a first-effect evaporator 7, a second-effect evaporator 8 and a third-effect evaporator 9 from the buffer tank 6, the temperature in the first-effect evaporator is 110 ℃, the pressure is normal pressure, the treatment time is 15min, the temperature in the second-effect evaporator is 100 ℃, the pressure is-10 Pa, the treatment time is 30min, the temperature in the third-effect evaporator is 94 ℃, the pressure is-0.02 Mpa, the treatment time is 25min, the materials are directly fed into an extruder 10 for granulation after impurities are removed through three-effect evaporation treatment, and then fed into a product tank 11, and the purity of N-methyl urea product is 96%.
Example 3
20Kg of urea particles and 18.4Kg of formic acid (99%) are respectively pumped into a reaction kettle 4 from a urea storage tank 1 and a formic acid storage tank 2, stirred for 1h and uniformly mixed, 45g of calcium carbonate and 60g of calcium oxide are pumped into the reaction kettle 4 from a catalyst storage tank 3, urea, formic acid and calcium carbonate fully react for 2.5h at the reaction temperature of 85 ℃, a part of reacted materials are conveyed into a buffer tank 6 through a centrifugal pump 5 and a part of the materials flow back to the reaction kettle 4, the reacted materials sequentially enter a first-effect evaporator 7, a second-effect evaporator 8 and a third-effect evaporator 9 from the buffer tank 6, the temperature in the first-effect evaporator is 109 ℃, the pressure is normal pressure, the treatment time is 40min, the temperature in the second-effect evaporator is 102 ℃, the pressure is-8 Pa, the treatment time is 10min, the temperature in the third-effect evaporator is 95 ℃, the pressure is-0.01 Mpa, the treatment time is 50min, impurities are removed by the three-effect evaporation treatment, the materials are directly fed into an extruder 10 for granulation, and then fed into a product tank 11, and the purity of the N-formylurea product is 98%.
Comparative example 1
10Kg of urea particles and 7.66Kg of formic acid (99%) are respectively pumped into a reaction kettle 4 from a urea storage tank 1 and a formic acid storage tank 2, stirred for 0.5h and uniformly mixed, 37g of concentrated phosphoric acid is pumped into the reaction kettle 4 from a catalyst storage tank 3, urea, formic acid and calcium oxide fully react for 2h, the reaction temperature is 95 ℃, a part of reacted materials are conveyed into a buffer tank 6 through a centrifugal pump 5, a part of the reacted materials are returned to the reaction kettle 4, the reacted materials sequentially enter a first-effect evaporator 7, a second-effect evaporator 8 and a third-effect evaporator 9 from the buffer tank 6, the temperature in the first-effect evaporator is 108 ℃, the pressure is normal pressure, the temperature in the second-effect evaporator is 103 ℃, the pressure is-6 Pa, the temperature in the third-effect evaporator is 92 ℃, the pressure is-0.03 MPa, the materials are directly fed into an extruder 10 for granulation after impurities are removed through the third-effect evaporation treatment, and then fed into a product tank 11, and the purity of N-formylurea product is 80%. The product is seriously agglomerated after long-time operation, and is easy to cause pipeline blockage.
Comparative example 2
10Kg of urea particles and 7.66Kg of formic acid (99%) are respectively pumped into a reaction kettle 4 from a urea storage tank 1 and a formic acid storage tank 2, stirred for 0.5h and uniformly mixed, 18.5g of calcium oxide is pumped into the reaction kettle 4 from a catalyst storage tank 3, urea, formic acid and calcium oxide fully react for 2h at the reaction temperature of 95 ℃, part of the reacted materials are conveyed into a buffer tank 6 through a centrifugal pump 5, the other part of the reacted materials are returned to the reaction kettle 4, the reacted materials enter a sedimentation tank from the buffer tank 6, the lower layer of sediment is conveyed into a rotary kiln for drying, the dried materials enter an extruder 10 for granulation, and then enter a product tank 11, and the purity of the N-formic acid urea product is 75%.
The above description is only of the preferred embodiments of the present application and is not intended to limit the present application, but various modifications and variations can be made to the present application by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.
Claims (4)
1. The continuous production process of the N-formylurea is characterized by comprising the following steps of:
S1: respectively conveying formic acid and urea into a reaction kettle;
S2: adding a catalyst into a reaction kettle;
S3: heating and stirring the mixed material in a reaction kettle to react for a period of time, separating out N-formylurea crystals, performing triple-effect evaporation treatment, and extruding and granulating;
in the step S2, the addition amount of the catalyst is 1-5 per mill of the mass of the total mixture of formic acid and urea;
The catalyst is one or two of calcium sulfate and calcium oxide.
2. The process according to claim 1, wherein in step S1, the molar ratio of urea to formic acid is 1:1-1.5.
3. The process according to claim 1, wherein in step S3, the reaction is carried out at 30-95 ℃ under normal pressure of 0.5-3 h.
4. A production process according to any one of claims 1 to 3, wherein in step S3, the triple effect evaporation is specifically: the temperature of the material in the first-effect evaporator is 110-120 ℃, the pressure is normal pressure, and the retention time is 5-60 min; the temperature of the material in the two-effect evaporator is 100-105 ℃, the pressure is-5 Pa to-10 Pa, and the retention time is 10-55 min; the temperature of the material in the triple effect evaporator is 90-95 ℃, the pressure is-0.01 to-0.05 MPa, and the retention time is 10-50 min.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310174858.9A CN116375605B (en) | 2023-02-28 | 2023-02-28 | Continuous N-formylurea production process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310174858.9A CN116375605B (en) | 2023-02-28 | 2023-02-28 | Continuous N-formylurea production process |
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| Publication Number | Publication Date |
|---|---|
| CN116375605A CN116375605A (en) | 2023-07-04 |
| CN116375605B true CN116375605B (en) | 2024-04-19 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310174858.9A Active CN116375605B (en) | 2023-02-28 | 2023-02-28 | Continuous N-formylurea production process |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116375605B (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106966865A (en) * | 2016-01-14 | 2017-07-21 | 天津市天地创智科技发展有限公司 | The system that a kind of technique in three-effect countercurrent evaporation rectification process handles glycine crystallization mother liquid |
| CN106966869A (en) * | 2016-01-14 | 2017-07-21 | 天津大学 | The system that a kind of four-effect evaporation rectification process handles glycine crystallization mother liquid |
| CN107698465A (en) * | 2017-11-14 | 2018-02-16 | 合肥祥晨化工有限公司 | A kind of synthetic method of acetylurea crystalline compounds |
-
2023
- 2023-02-28 CN CN202310174858.9A patent/CN116375605B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106966865A (en) * | 2016-01-14 | 2017-07-21 | 天津市天地创智科技发展有限公司 | The system that a kind of technique in three-effect countercurrent evaporation rectification process handles glycine crystallization mother liquid |
| CN106966869A (en) * | 2016-01-14 | 2017-07-21 | 天津大学 | The system that a kind of four-effect evaporation rectification process handles glycine crystallization mother liquid |
| CN107698465A (en) * | 2017-11-14 | 2018-02-16 | 合肥祥晨化工有限公司 | A kind of synthetic method of acetylurea crystalline compounds |
Non-Patent Citations (1)
| Title |
|---|
| THE SYNTHESIS OF ETHYL-(1-METHYLBUTYL)- AND ETHYLISOAMYL-MALONURIC ACIDS;W. MAYNERT等;《Journal of Organic Chemistry》;19501231;259-263 * |
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| CN116375605A (en) | 2023-07-04 |
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