CN103896811B - The method of hexa-methylene diamino-methyl formate is prepared in a kind of heterogeneous catalysis - Google Patents

The method of hexa-methylene diamino-methyl formate is prepared in a kind of heterogeneous catalysis Download PDF

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CN103896811B
CN103896811B CN201210584767.4A CN201210584767A CN103896811B CN 103896811 B CN103896811 B CN 103896811B CN 201210584767 A CN201210584767 A CN 201210584767A CN 103896811 B CN103896811 B CN 103896811B
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hexanediamine
methyl formate
diamino
catalyzer
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CN103896811A (en
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李会泉
李新涛
曹妍
王利国
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Institute of Process Engineering of CAS
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Abstract

The present invention relates to a kind of method that hexa-methylene diamino-methyl formate is prepared in heterogeneous catalysis.The present invention for reactant with alkyl carbamate and hexanediamine, selects metal oxide catalyst, adopts two sections of alternating temperature reaction process to carry out Reactive Synthesis hexa-methylene diamino-methyl formate, constantly pass into rare gas element, shift out by product ammonia in reaction process.After reaction terminates, filtered while hot removing catalyzer, namely gained liquid obtain the own diamino-methyl formate of white solid after underpressure distillation.Adopt this method reaction conditions gentle, pollution-free, operating process is easy, and potential safety hazard is little, and catalyzer used is easy to be separated, and can repeatedly use, have good prospects for commercial application.

Description

The method of hexa-methylene diamino-methyl formate is prepared in a kind of heterogeneous catalysis
Technical field
The invention belongs to a kind of method that hexa-methylene diamino-methyl formate is prepared in heterogeneous catalysis, in particular to one hexanediamine and alkyl formate ester as raw material under metal oxide catalyst effect, adopt the method for two sections of alternating temperature reaction process synthesizing hexamethylene diamino-methyl formates.
Background technology
Isocyanic ester is a kind of important organic intermediate, is widely used in the production of elastomerics, coating, plastics, agricultural chemicals and leather etc.Wherein, hexamethylene diisocyanate (HDI) applies wider aliphatic isocyanates, its derivative have do not turn yellow, anti-powdering, the advantage such as wear-resisting, extensive application in the binding agent etc. of carplane OEM coating, retouching paint, high-grade wood furniture paint, anticorrosive coating and good light stability.
At present, HDI mainly adopts phosgenation to produce.The method uses the phosgene of severe toxicity to make raw material, the hydrochloric acid that by-product is a large amount of, and production equipment is complicated, and high to equipment requirements, process flow is many, and equipment corrosion, phosgene leakage accident very easily occur, serious environment pollution, threat personnel safety.Along with the raising of people's environmental protection consciousness, the clean synthetic route of various non-phosgene greens becomes the focus of research.Wherein, carbamate pyrolysis method is the most promising method.When adopting this method to produce HDI, mainly comprise synthesis and pyrolysis two step thereof of intermediate hexa-methylene diamino-methyl formate (HDC).
About the synthesis of HDC, what report was more at present is hexanediamine (HDA) and methylcarbonate (DMC) aminolysis reaction method, and the key of technology is the research of catalyzer.All adopt sodium methylate to make catalyzer in US5789614 and EP0570070, the method HDA transformation efficiency is high, but side reaction is serious, and target product productive rate is very low.CN1727330A adopts Pb compound, and reaction conditions is gentle, and yield and selectivity can reach more than 98%.Although homogeneous catalyst good catalytic activity, its easy in inactivation, is separated and reclaims difficulty, limits it and uses.In order to overcome its drawback, the people such as Lu Ling have studied loading type MgO, ZrO respectively 2/ SiO 2deng the catalytic effect of heterogeneous catalyst, but its yield is lower, does not have industrial application value.Have studied solvent and catalyzer that ionic liquid reacts as amine and DMC in CN02158320, show multiple outstanding performance, HDC yield more than 98%, but ionic liquid synthesis difficulty, price are higher, limit its application.
The synthetic route that another kind has future with small molecules alkyl carbamate such as Urethylane (MC), urethanum (EC) etc. with amine Reactive Synthesis carbamate.EP0018588, WO9717323 disclose a kind of method being prepared aliphatic carbamate by small molecules alkyl carbamate and the reaction such as hexahydroaniline, hexanediamine, but its temperature of reaction is high, and side reaction is serious, and yield is lower.CN101928238A discloses a kind of method adopting small molecules alkyl carbamate and hexanediamine reaction to prepare HDC, and it adopts the Lewis acid catalysts such as homogeneous phase Yttrium trinitrate, lanthanum nitrate, and difficult separation and recycling, limits it and use further.Meanwhile, this reacting quintessence belongs to urea alcoholysis reaction, comprising generation and alcoholysis two step thereof of oneself two ureas, is a succession of reaction.Wherein, alcoholysis reaction needs temperature higher, and between 170-210 ° of C, therefore the higher temperature of whole reaction needed just can reach reasonable effect.But hexanediamine has greater activity, at high temperature easy and alkyl carbamate produces polyureas, reduces the selectivity of reaction.Therefore, need to develop novel process to reduce generation, the raising object selectivity of product of by product.
Summary of the invention
The technology of the present invention is dealt with problems: overcome the deficiencies in the prior art, a kind of heterogeneous metal oxide catalyst catalytic amino alkyl formate and hexanediamine is provided to synthesize the method for own diamino-methyl formate through two sections of alternating temperature reaction process, adopt the method reaction conditions gentle, pollution-free, operating process is easy, and potential safety hazard is little, and catalyzer used is easy to be separated, can repeatedly use, there is good prospects for commercial application.
The present invention is achieved by the following technical solutions:
(1) catalyst preparing
1. one-step calcinations: metal-salt is placed in retort furnace roasting 2-10h under 200-1000 ° of C air atmosphere, porphyrize calcining matter, obtains corresponding metal oxide.
2. the precipitator method: metal-salt is dissolved in appropriate amount of deionized water or ethanol, uses Na 2cO 3or ammoniacal liquor slowly adds in solution, aging 2-10h, filters, and washing, gained solid is placed in retort furnace roasting 2-10h under 200-1000 ° of C air atmosphere after drying, and porphyrize calcining matter, obtains corresponding metal oxide.
(2) reaction process
Appropriate alkyl carbamate, hexanediamine, solvent and oxide catalyst are added in the autoclave with condenser, adopt two sections of alternating temperature reaction process to react, constantly pass into rare gas element in reaction process, shift out byproduct of reaction ammonia.After reaction terminates, filtered while hot removing catalyzer, namely gained liquid obtain the own diamino-methyl formate of white solid after underpressure distillation.Filter gained catalyzer after washing, can repeatedly reuse.
Described alkyl carbamate comprises the alkyl esters such as Urethylane, urethanum, carboxylamine propyl ester, butyl carbamate.
Described metal oxide comprises: CeO 2, TiO 2, MoO 3, ZrO 2, ZnO, Bi 2o 3, Fe 2o 3, La 2o 3, SnO 2, Y 2o 3deng, can be one wherein, two or more oxide compounds.
Described reaction solvent comprises methyl alcohol, ethanol, propyl alcohol, propyl carbinol, chlorobenzene, toluene, dichlorobenzene etc., and can be single solvent, also can be two or more mixed solvents.
The mol ratio of described small molecules alkyl carbamate and hexanediamine is 2:1-15:1.
The mol ratio of described solvent and hexanediamine is 5:1-50:1, preferred 10:1-30:1.
The mass ratio of described catalyzer and hexanediamine is 0.5%-20%, preferred 5%-15%.
Two sections of described alternating temperature reaction process specifically comprise: (one) first paragraph temperature of reaction 100-150 ° of C, reaction times 2-10h; (2) second segment temperature of reaction 170-210 ° of C, reaction times 4-8h.
Described rare gas element is have the gas reacted in not impact system under temperature of reaction condition, comprises nitrogen, helium, argon gas.
The present invention's advantage is compared with prior art:
(1) the present invention adopts alkyl carbamate to replace phosgene, and reaction conditions is gentle, and pollution-free, operating process is easy, and potential safety hazard is little.
(2) catalyzer that the present invention uses is heterogeneous catalyst, is easy to reclaim, has good industrial prospect.
(3) catalyst source that adopts of the present invention is extensive, and preparation is simple, only needs corresponding metal-salt or basic salt to precipitate roasting in the basic conditions.
(4) two sections of alternating temperature reaction process that the present invention adopts pass through the generation temperature reducing oneself two ureas, and significantly can reduce the generation of by product polyureas, improve object selectivity of product, own diamino-methyl formate yield is more than 90%, and hexanediamine transformation efficiency is 100%.
Embodiment
In order to further illustrate details of the present invention, below for some embodiments, but should not be so limited.
Embodiment 1
Get appropriate cerous nitrate in crucible, dry 4h in 110 ° of C baking ovens, and then in 600 ° of C roasting 4h in retort furnace.By calcining matter porphyrize, obtain solid CeO 2catalyzer.Appropriate hexanediamine, Urethylane, methyl alcohol (mol ratio is 1:2:5) are added in the autoclave with prolong, adds the CeO of mass ratio 0.5% simultaneously 2, be warming up to 150 ° of C and react 2h, and then be warming up to 210 ° of C reaction 4h.Constantly pass into nitrogen in reaction process, produce by product ammonia and be constantly discharged.After reaction terminates, filtered while hot removing catalyzer, namely the underpressure distillation under 60 ° of C, 1KPa conditions of gained liquid obtains the own diamino-methyl formate of white solid.Filter gained catalyzer after washing, can repeatedly reuse.
Reaction result: hexanediamine transformation efficiency is 100%, own diamino-methyl formate yield is 96.9%.
Embodiment 2
Get appropriate zirconium nitrate to be dissolved in 100ml deionized water, use 1mol/LNa 2cO 3slowly add in solution, aging 10h, filter, washing, gained solid is placed in retort furnace roasting 10h under 200 ° of C air atmospheres after drying, and porphyrize calcining matter, obtains ZrO 2oxide compound.Appropriate hexanediamine, Urethylane, methyl alcohol and chlorobenzene mixed solvent (mol ratio is 1:5:10) are added in the autoclave with prolong, adds the ZrO of mass ratio 5% simultaneously 2, be warming up to 100 ° of C and react 10h, and then be warming up to 170 ° of C reaction 8h.Constantly pass into helium in reaction process, produce by product ammonia and be constantly discharged.After reaction terminates, filtered while hot removing catalyzer, namely the underpressure distillation under 130 ° of C, 15KPa conditions of gained liquid obtains the own diamino-methyl formate of white solid.Filter gained catalyzer after washing, can repeatedly reuse.
Reaction result: hexanediamine transformation efficiency is 100%, own diamino-methyl formate yield is 90.9%.
Embodiment 3
Get appropriate nitric acid molybdenum in crucible, dry 4h in 110 ° of C baking ovens, and then in 1000 ° of C roasting 2h in retort furnace.By calcining matter porphyrize, obtain solid MoO 3catalyzer.Appropriate hexanediamine, urethanum, ethanol and toluene Mixed Solvent (mol ratio is 1:7:15) are added in the autoclave with prolong, adds the MoO of mass ratio 10% simultaneously 3, be warming up to 140 ° of C and react 3h, and then be warming up to 200 ° of C reaction 5h.Constantly pass into argon gas in reaction process, produce by product ammonia and be constantly discharged.After reaction terminates, filtered while hot removing catalyzer, namely the underpressure distillation under 150 ° of C, 30KPa conditions of gained liquid obtains the own diamino-methyl formate of white solid.Filter gained catalyzer after washing, can repeatedly reuse.
Reaction result: hexanediamine transformation efficiency is 100%, own diamino-methyl formate yield is 92.9%.
Embodiment 4
Get appropriate zirconium nitrate, cerous nitrate is dissolved in 100ml deionized water, slowly add in solution with 1mol/L ammoniacal liquor, aging 10h, filter, washing, gained solid is placed in retort furnace roasting 6h under 800 ° of C air atmospheres after drying, porphyrize calcining matter, obtains ZrO-CeO 2composite catalyst.Appropriate hexanediamine, Urethylane, methyl alcohol (mol ratio is 1:10:20) are added in the autoclave with prolong, adds the ZrO-CeO of mass ratio 15% simultaneously 2composite catalyst, is warming up to 130 ° of C and reacts 5h, and then is warming up to 190 ° of C reaction 6h.Constantly pass into nitrogen in reaction process, produce by product ammonia and be constantly discharged.After reaction terminates, filtered while hot removing catalyzer, namely the underpressure distillation under 90 ° of C, 5KPa conditions of gained liquid obtains the own diamino-methyl formate of white solid.Filter gained catalyzer after washing, can repeatedly reuse.
Reaction result: hexanediamine transformation efficiency is 100%, own diamino-methyl formate yield is 91.1%.
Embodiment 5
Getting appropriate tetrabutyl titanate is dissolved in 100ml ethanol, slowly adds in solution, aging 10h with 1mol/L ammoniacal liquor, filters, and washing, gained solid is placed in retort furnace roasting 7h under 600 ° of C air atmospheres after drying, and porphyrize calcining matter, obtains TiO 2catalyzer.Appropriate hexanediamine, butyl carbamate, propyl carbinol (mol ratio is 1:15:25) are added in the autoclave with prolong, adds the TiO of mass ratio 20% simultaneously 2, be warming up to 110 ° of C and react 8h, and then be warming up to 180 ° of C reaction 7h.Constantly pass into argon gas in reaction process, produce by product ammonia and be constantly discharged.After reaction terminates, filtered while hot removing catalyzer, namely the underpressure distillation under 130 ° of C, 15KPa conditions of gained liquid obtains the own diamino-methyl formate of white solid.Filter gained catalyzer after washing, can repeatedly reuse.
Reaction result: hexanediamine transformation efficiency is 100%, own diamino-methyl formate yield is 90.5%.
Embodiment 6
Get appropriate zinc nitrate, Bismuth trinitrate, lanthanum nitrate be dissolved in 100ml deionized water, slowly add in solution with 1mol/L ammoniacal liquor, aging 10h, filter, washing, gained solid is placed in retort furnace roasting 6h under 700 ° of C air atmospheres after drying, porphyrize calcining matter, obtains ZnO-Bi 2o 3-La 2o 3composite catalyst.Appropriate hexanediamine, butyl carbamate, propyl carbinol and dichlorobenzene mixed solvent (mol ratio is 1:15:30) are added in the autoclave with prolong, adds the ZnO-Bi of mass ratio 7.5% simultaneously 2o 3-La 2o 3, be warming up to 120 ° of C and react 7h, and then be warming up to 180 ° of C reaction 7h.Constantly pass into helium in reaction process, produce by product ammonia and be constantly discharged.After reaction terminates, filtered while hot removing catalyzer, namely the underpressure distillation under 120 ° of C, 12KPa conditions of gained liquid obtains the own diamino-methyl formate of white solid.Filter gained catalyzer after washing, can repeatedly reuse.
Reaction result: hexanediamine transformation efficiency is 100%, own diamino-methyl formate yield is 94.9%.
It should be noted that, according to the various embodiments described above of the present invention, those skilled in the art are the four corners that can realize independent claim of the present invention and appurtenance completely, implementation procedure and the same the various embodiments described above of method; And non-elaborated part of the present invention belongs to techniques well known.
The above; be only part embodiment of the present invention, but protection scope of the present invention is not limited thereto, any those skilled in the art are in the technical scope that the present invention discloses; the change that can expect easily or replacement, all should be encompassed within protection scope of the present invention.

Claims (7)

1. a method for hexa-methylene diamino-methyl formate is prepared in heterogeneous catalysis, it is characterized in that reaction process is:
A, reactant alkyl carbamate, hexanediamine, metal oxide catalyst and solvent are added in autoclave according to certain mol ratio; The mol ratio of described alkyl carbamate and hexanediamine is 2:1-15:1; The mol ratio of described solvent and hexanediamine is 5:1-50:1; The mass ratio of described metal oxide catalyst and hexanediamine is 0.5%-20%; Described metal oxide catalyst is CeO 2, TiO 2, MoO 3, ZrO 2, ZnO, Bi 2o 3, Fe 3o 4, La 2o 3, SnO 2, Y 2o 3one in oxide compound, two or more combinations;
B, employing two sections of alternating temperature reaction process catalyze and synthesize own diamino-methyl formate, detailed process is for be first heated to first paragraph thermotonus for some time by autoclave, then autoclave is warming up to second segment temperature and continues reaction for some time, reaction terminates rear cooling and obtains reaction mixture; In reaction process Keep agitation not open close enter rare gas element, shift out by product ammonia; In described two sections of alternating temperature reaction process, first paragraph temperature of reaction is 100-150 DEG C, reaction times 2-10h; Second segment temperature of reaction 170-210 DEG C, reaction times 4-8h;
After c, reaction terminate, filtered while hot reaction solution removing catalyzer, namely gained liquid obtain the own diamino-methyl formate of white solid after underpressure distillation; Catalyzer uses through washing Posterior circle.
2. method according to claim 1, is characterized in that: described reactant alkyl carbamate is selected from Urethylane, urethanum, carboxylamine propyl ester or butyl carbamate.
3. method according to claim 1, is characterized in that: described reaction solvent comprises methyl alcohol, ethanol, propyl alcohol, propyl carbinol, chlorobenzene, toluene or dichlorobenzene, can be single solvent, also can be two or more mixed solvents.
4. method according to claim 1, is characterized in that: the mol ratio of described solvent and hexanediamine is 10:1-30:1.
5. method according to claim 1, is characterized in that: the mass ratio of described catalyzer and hexanediamine is 5%-15%.
6. method according to claim 1, is characterized in that: described underpressure distillation separation temperature is 60-150 DEG C, and pressure is 1-30KPa.
7. method according to claim 1, is characterized in that: described rare gas element is nitrogen, helium or argon gas.
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