CN105503656B - A kind of preparation method of carbodiimide - Google Patents
A kind of preparation method of carbodiimide Download PDFInfo
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- CN105503656B CN105503656B CN201610104798.3A CN201610104798A CN105503656B CN 105503656 B CN105503656 B CN 105503656B CN 201610104798 A CN201610104798 A CN 201610104798A CN 105503656 B CN105503656 B CN 105503656B
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C267/00—Carbodiimides
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
- B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
- B01J31/0277—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides comprising ionic liquids, as components in catalyst systems or catalysts per se, the ionic liquid compounds being used in the molten state at the respective reaction temperature
- B01J31/0278—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides comprising ionic liquids, as components in catalyst systems or catalysts per se, the ionic liquid compounds being used in the molten state at the respective reaction temperature containing nitrogen as cationic centre
- B01J31/0281—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides comprising ionic liquids, as components in catalyst systems or catalysts per se, the ionic liquid compounds being used in the molten state at the respective reaction temperature containing nitrogen as cationic centre the nitrogen being a ring member
- B01J31/0284—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides comprising ionic liquids, as components in catalyst systems or catalysts per se, the ionic liquid compounds being used in the molten state at the respective reaction temperature containing nitrogen as cationic centre the nitrogen being a ring member of an aromatic ring, e.g. pyridinium
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
- B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
- B01J31/12—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides containing organo-metallic compounds or metal hydrides
- B01J31/122—Metal aryl or alkyl compounds
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
- B01J31/26—Catalysts comprising hydrides, coordination complexes or organic compounds containing in addition, inorganic metal compounds not provided for in groups B01J31/02 - B01J31/24
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2231/00—Catalytic reactions performed with catalysts classified in B01J31/00
- B01J2231/50—Redistribution or isomerisation reactions of C-C, C=C or C-C triple bonds
- B01J2231/52—Isomerisation reactions
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- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
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- Inorganic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
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Abstract
The present invention relates to a kind of preparation method of carbodiimide, using dicyclohexylurea (DCU) (DCU) and solid phosgene (BTC) as raw material, using composite catalyst, dicyclohexylcarbodiimide is prepared, it is characterised in that:Composite catalyst is the compounding mixture of rare earth compound and ionic liquid.The method of the present invention can optimize the yield and purity of carbodiimide.
Description
Technical field
The present invention relates to a kind of method for preparing carbodiimide, belong to synthesis chemical field.
Background technology
Dicyclohexylcarbodiimide (DCC), N, N'- DIC (DIC), 1- (3- dimethylamino-propyls)-
3- ethyl-carbodiimide hydrochlorides (EDC) are most common three kinds of carbodiimides.It is general that hydrogen sulfide or urea dehydration system are lost by thiocarbamide
It is standby.
CN101096349A discloses a kind of preparation method of DCC, by cyclohexylamine and carbon disulfide reaction two hexamethylenes of generation
Base thiocarbamide and vulcanized sodium, dicyclohexyl thiourea generate DCC through sodium hypochlorite secondary oxidation depriving hydrogen sulphide.Wherein thiocarbamide is through hypochlorous acid
When sodium is aoxidized, while adding catalyst to be reacted, catalyst uses triethyl benzyl ammonia chloride TEBA or polyethylene glycol PEG.
CN101524650A discloses a kind of preparation method of DCC, and it uses organophosphor solid polymer catalyst system.
Dicyclohexylcarbodiimide is obtained for cyclohexyl isocyanate catalyzing and condensing.
Some researchs have been done in terms of the preparation method of carbodiimide by Chizhou Wanwei Chemical Industry Co., Ltd.CN101538225A
Disclose it is a kind of for resistant to hydrolysis in terms of dual-carbodiimide class compound.CN101628882A discloses a kind of N, N '-two (2,
6- diisopropyl phenyls) carbodiimide preparation method, wherein using copper chloride as catalyst.
CN102408335A discloses a kind of preparation method of DCC, and it uses dicyclohexylurea (DCU) and double (trichloromethyl) carbon
Acid esters is raw material.Due to using double (trichloromethyl) carbonic esters of solid phosgene, reducing traditional handicraft security hidden trouble.
Ji'nan Healtang Biotechnology Co., Ltd. have also been made some researchs in terms of carbodiimide preparation technology.
CN102643215A discloses a kind of preparation method of carbodiimide, wherein using cupric sulfate pentahydrate as catalysis
Agent, because the catalyst has color change effect, constantly sampling detects this program to eliminate needs.CN102775329A is public
A kind of preparation method of carbodiimide is opened, wherein using acid binding agent, phase transfer catalyst and desulfurizing agent.Using solid base as
Acid binding agent, phase transfer catalyst enhancing deacidification effect, yield is up to 91%.
CN103382168A discloses a kind of preparation technology of DIC, and it uses sodium hypochlorite as catalyst.
CN103922970A discloses a kind of preparation method of DCC, and it uses catalyst and reaction promoter, wherein catalyst
It is the mixture of mantoquita, nickel salt and cerous nitrate salt as ternary Industrial Catalysis system.Reaction promoter is lauryl sodium sulfate class.
The technique has the advantages that high income, reacts fast, high safety.
CN104193653A discloses a kind of preparation method of DCC, and it is using only neopelex class as helping
Agent, does not use organic solvent.
As fully visible, it is catalyst system and catalyzing for the more focus of the improvement of technique.
In order to further optimize the process conditions of DCC preparation methods, yield and purity are improved, while it is hidden to reduce process safety
Suffer from and waste water pollution problem, propose technical scheme.
The content of the invention
The technical problem to be solved in the present invention is further optimum synthesis technique, there is provided a kind of method for preparing DCC.It is a kind of
The preparation method of dicyclohexylcarbodiimide, using dicyclohexylurea (DCU) (DCU) and solid phosgene (BTC) as raw material, using compound
Catalyst, prepares dicyclohexylcarbodiimide, it is characterised in that:Composite catalyst is rare earth compound and ionic liquid
Compounding mixture.
Preferably, the preparation method of DCC comprises the following steps:At room temperature to addition solvent and dicyclohexyl in reactor
Urea, then stirs, and adds solid phosgene, then adds composite catalyst, rises high-temperature, insulated and stirred reaction, reaction
After finishing, pH adjusting agent is added to adjust pH value to 7-8, then suction filtration while hot, by gained filtrate steaming removal solvent, vacuum distillation is received
The cut of 155 ± 1 DEG C of collection, obtains DCC after vacuum drying.
Preferably, rare earth compound is selected from one or more in rare earth oxide, rare earth sulfonate.It is further preferred that
Rare earth compound is rare earth sulfonate Ln (RSO3)3, wherein R is phenyl, and Ln is lanthanum, neodymium or yttrium.
Preferably, ionic liquid is one or more in imidazole type ion liquid or pyridine type ionic liquid.It is more excellent
Selection of land, ionic liquid is selected from pyridine type ionic liquid, is 1- butyl -3- picolines tetrafluoroborate, N- hexyl -3- methyl pyrroles
Pyridine mesylate or N- octyl group -3- picoline tetrafluoroborates.Imidazole type ion liquid can be 1,3- methylimidazoles four
Borofluoride, 1,3- methylimidazoles tosilate, 1- butyl -3- methylimidazole fluoroform sulphonates etc..
Preferably, rare earth compound and the weight ratio of ionic liquid are 1:0.4-0.6.
Preferably, DCU and the mass ratio of composite catalyst are 1:0.0001-0.0005, more preferably 1:0.0002-
0.0003。
In a preferred scheme, the mass ratio of DCU and BTC is 1:2-3.
Preferably, solvent is selected from t-butyl methyl ether, NMP etc..
DCU uses conventional consumption, such as 1 with the mass ratio of solvent:8-12g/ml.Reaction temperature is 20-60 DEG C, excellent
Elect 30-40 DEG C as.Reaction time is 3-10h, preferably 5-8h.
The present invention has following obvious advantage compared with prior art:
Novel composite catalyst is developed, reaction yield is optimized, product purity is improve.
Specific embodiment
The preferred embodiments of the present invention are illustrated below, it will be appreciated that preferred embodiment described herein is only used
In the description and interpretation present invention, it is not intended to limit the present invention.
Embodiment 1:
To the NMP and 100gDCU that 1000ml is added in reactor at 30 DEG C, stir, add 200gBTC, Ran Houjia
(DCU is 1 with the amount ratio of composite catalyst to enter composite catalyst:0.0001) high-temperature to 40 DEG C, insulated and stirred reaction, are risen
6h, after completion of the reaction, adds triethylamine regulation pH to 7.5, while hot suction filtration, and normal pressure is evaporated off solvent, and then vacuum distillation is collected
155 ± 1 DEG C of cut, white crystalline solid DCC is obtained after being vacuum dried in an oven.Wherein composite catalyst is rare earth sulfonic acid
Salt and ionic liquid mass ratio are 1:0.4 mixture;Its middle rare earth sulfonate is Ln (RSO3)3, R is phenyl, and Ln is lanthanum;From
Sub- liquid is N- hexyl -3- picoline mesylates.
Embodiment 1-a
Wherein ionic liquid is 1,3- methylimidazole tosilate, the other the same as in Example 1.
Embodiment 1-b
Wherein rare earth compound is Ln2O3, the other the same as in Example 1.
Embodiment 1-c
Wherein ionic liquid is piperidines type ionic liquid N-methyl, propylpiperdine hexafluorophosphate, the other the same as in Example 1.
Embodiment 1-d
Wherein ionic liquid is pyrrolidines type ionic liquid N-methyl-butvl pyrrolidines tetrafluoroborate, and other are with implementation
Example 1.
Embodiment 1-e
Wherein rare earth compound is rare earth halide LnCl3, the other the same as in Example 1.
Embodiment 1-f
Wherein rare earth compound is rare earth carboxylate Ln (RCOO)3, R is 2- ethyl pentyl groups, the other the same as in Example 1.As a result
It is shown in Table 1.
Table 1:The selectivity of ionic liquid and rare earth compound
From the point of view of the result of table 1, rare earth compound is preferably rare earth oxide, more preferably rare earth sulfonate, rare earth
Sulfonate.Ionic liquid is preferably imidazole type ion liquid or pyridine type ionic liquid, more preferably pyridine type ionic liquid.
Embodiment 2
DCU is 1 with the amount ratio of composite catalyst:0.0002, the other the same as in Example 1.
Embodiment 2-a
DCU is 1 with the amount ratio of composite catalyst:0.0005, the other the same as in Example 2.
Embodiment 2-b
DCU is 1 with the amount ratio of composite catalyst:0.0003, the other the same as in Example 2.
Embodiment 2-c
DCU is 1 with the amount ratio of composite catalyst:0.001, the other the same as in Example 2.The results are shown in Table 2.
Table 2:The amount ratio of DCU and composite catalyst
Numbering | The amount ratio of DCU and composite catalyst | Product yield/% | Purity/% |
Embodiment 1 | 1:0.0001 | 99.0 | 97.2 |
Embodiment 2 | 1:0.0002 | 99.5 | 99.1 |
Embodiment 2-a | 1:0.0005 | 99.1 | 97.3 |
Embodiment 2-b | 1:0.0003 | 99.4 | 99.0 |
Embodiment 2-c | 1:0.001 | 98.4 | 96.2 |
From the point of view of the result of table 2, DCU is preferably 1 with the amount ratio of composite catalyst:0.0001-0.0005, more preferably
It is 1:0.0002-0.0003.Ratio is too high or too low all to influence product yield and purity.
Embodiment 3
Rare earth sulfonate and ionic liquid mass ratio are 1:0.6, the other the same as in Example 1.
Embodiment 3-a
Rare earth sulfonate and ionic liquid mass ratio are 1:0.3, the other the same as in Example 3.
Embodiment 3-b
Rare earth sulfonate and ionic liquid mass ratio are 1:0.8, the other the same as in Example 3.
Embodiment 3-c
Rare earth sulfonate and ionic liquid mass ratio are 1:1, the other the same as in Example 3.
Embodiment 3-d
Rare earth sulfonate and ionic liquid mass ratio are 1:0.1, the other the same as in Example 3.The results are shown in Table 3.
Table 3:Rare earth sulfonate and ionic liquid mass ratio
Numbering | Rare earth sulfonate and ionic liquid mass ratio | Product yield/% | Purity/% |
Embodiment 1 | 1:0.4 | 99.0 | 97.2 |
Embodiment 3 | 1:0.6 | 99.4 | 97.5 |
Embodiment 3-a | 1:0.3 | 98.5 | 96.2 |
Embodiment 3-b | 1:0.8 | 99.0 | 97.1 |
Embodiment 3-c | 1:1 | 99.1 | 97.3 |
Embodiment 3-d | 1:0.1 | 98.0 | 97.0 |
From the point of view of the result of table 3, rare earth sulfonate and ionic liquid mass ratio are preferably 1:0.4-0.6.If ratio is too high,
Improve few for product yield and purity, cost is raised, if ratio is too low, can influence yield and purity.
The preferred embodiments of the present invention are the foregoing is only, is not intended to limit the invention, although with reference to foregoing reality
Apply example to be described in detail the present invention, for a person skilled in the art, it still can be to foregoing each implementation
Technical scheme described in example is modified, or carries out equivalent to which part technical characteristic.It is all in essence of the invention
Within god and principle, any modification, equivalent substitution and improvements made etc. should be included within the scope of the present invention.
Claims (9)
1. a kind of preparation method of carbodiimide, using dicyclohexylurea (DCU) (DCU) and solid phosgene (BTC) as raw material, using multiple
Catalyst is closed, dicyclohexylcarbodiimide is prepared, it is characterised in that:Composite catalyst is rare earth compound and ionic liquid
Compounding mixture;Rare earth compound is selected from one or more in rare earth oxide, rare earth sulfonate;Ionic liquid is imidazoles
One or more in type ionic liquid or pyridine type ionic liquid;
Rare earth oxide is Ln2O3;
Rare earth sulfonate is Ln (RSO3)3, wherein R is phenyl, and Ln is lanthanum, neodymium or yttrium;
Imidazole type ion liquid is 1,3- methylimidazoles tetrafluoroborate, 1,3- methylimidazoles tosilate, 1- fourths
Base -3- methylimidazole fluoroform sulphonates;
Pyridine type ionic liquid is 1- butyl -3- picolines tetrafluoroborate, N- hexyls -3- picolines mesylate or N-
Octyl group -3- picoline tetrafluoroborates.
2. preparation method according to claim 1, it is characterised in that:Comprise the following steps:Add in reactor at room temperature
Enter solvent and dicyclohexylurea (DCU), then stir, add solid phosgene, then add composite catalyst, rise high-temperature, protect
Warm stirring reaction, after completion of the reaction, adds pH adjusting agent to adjust pH value to 7-8, then suction filtration while hot, gained filtrate is evaporated off molten
155 ± 1 DEG C of cut is collected in agent, vacuum distillation, and DCC is obtained after vacuum drying.
3. preparation method according to claim 1, it is characterised in that:Rare earth compound is 1 with the weight ratio of ionic liquid:
0.4-0.6。
4. preparation method according to claim 1, it is characterised in that:DCU is 1 with the mass ratio of composite catalyst:
0.0001-0.0005。
5. preparation method according to claim 4, it is characterised in that:DCU is 1 with the mass ratio of composite catalyst:
0.0002-0.0003。
6. preparation method according to claim 1, it is characterised in that:The mass ratio of DCU and BTC is 1:2-3.
7. preparation method according to claim 2, it is characterised in that:Solvent is selected from t-butyl methyl ether, NMP.
8. preparation method according to claim 2, it is characterised in that:DCU uses conventional use with the mass ratio of solvent
Amount, 1:8-12g/ml;Reaction temperature is 20-60 DEG C;Reaction time is 3-10h.
9. preparation method according to claim 8, it is characterised in that:Reaction temperature is 30-40 DEG C;Reaction time is 5-
8h。
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CN109503429A (en) * | 2018-11-23 | 2019-03-22 | 山东汇海医药化工有限公司 | A kind of method of raising N, N '-dicyclohexylcarbodiimide product purity |
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CN102408355A (en) * | 2011-11-24 | 2012-04-11 | 浙江工业大学 | Method for synthesizing dicyclohexylcarbodiimide compound |
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