CN101429139B - Process for producing dicyclohexyl methyl hydride diisocyanate and its midbody - Google Patents
Process for producing dicyclohexyl methyl hydride diisocyanate and its midbody Download PDFInfo
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- CN101429139B CN101429139B CN200810188128XA CN200810188128A CN101429139B CN 101429139 B CN101429139 B CN 101429139B CN 200810188128X A CN200810188128X A CN 200810188128XA CN 200810188128 A CN200810188128 A CN 200810188128A CN 101429139 B CN101429139 B CN 101429139B
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Abstract
The invention discloses a method for preparing dicyclohexyl methane diisocyanate. The method comprises the following steps: a) a diamino diphenylmethane isomer mixture reacts in an organic solvent at a reaction temperature between 90 and 200 DEG C, under the hydrogen pressure between 3.0 and 12.0 MPa and under the action of a catalyst, so as to obtain a diamino dicyclohexyl methane isomer mixture; and b) the diamino dicyclohexyl methane isomer mixture obtained in the step a) and phosgene are heated to 330 to 400 DEG C so as to be gasify respectively and then are sent into a reactor with a mixing device to be mixed and react, have hydrogen chloride and phosgene removed, and are distilled, so as to obtain the dicyclohexyl methane diisocyanate. The method has the advantages of prolonging the life span of the catalyst and reducing cost. The invention also provides a complete technological process for preparing the dicyclohexyl methane diisocyanate.
Description
Technical field
The present invention relates to a kind of vulcabond and intermediates preparation thereof; Be specifically related to a kind ofly 4,4 '-dicyclohexyl methane diisocyanate quality percentage composition is dicyclohexyl methane diisocyanate isomer mixture and the intermediates preparation thereof of 48%-100%.
Background technology
Diamino-dicyclohexyl methane (H
12MDA), be also referred to as the hydrogenation diaminodiphenyl-methane, can be used for epoxy curing agent, and as preparation dicyclohexyl methane diisocyanate (H
12MDI) raw material.Common H
12MDA can obtain through diaminodiphenyl-methane shortening under high pressure, then H
12MDA can obtain H through phosgenation again
12MDI.
And general employing of the starting raw material of preparation diamino-dicyclohexyl methane contained diaminodiphenyl-methane and (is called for short: dicyclo MDA) with the mixture of the higher homologue of diamino-diphenyl diamines (abbreviation: polyamines, encircle MDA) more.When adopting this raw material, impurity that contains in the raw material such as impurity such as isomer, oligopolymer can cause activity of such catalysts to reduce rapidly when hydrogenation, shorten the life in catalyzer longevity, and the production cost in the commercial run is raise.
To above-mentioned technological deficiency; US3959374 discloses and has a kind ofly carried out the method that hydrogenation prepares diamino-dicyclohexyl methane with two-step approach to containing the small amount of impurities diaminodiphenyl-methane; At first use the lower nickel catalyzator of a kind of value that the thick diaminodiphenyl-methane that contains impurity is carried out the hydrogenation pre-treatment, the higher ruthenium catalyst of use value carries out the second step hydrogenation then.Ruthenium catalyst can overcome that productive rate when using nickel catalyzator is low, the shortcoming of long reaction time; But ruthenium catalyst is poisoned by impurities in raw materials such as isomer impurities easily; Cause active reduction rapidly; Thereby adopt and at first to carry out pretreated method with nickel catalyzator, can reduce in the raw material impurity like this to the murder by poisoning of ruthenium catalyst, help prolonging ruthenium catalyst work-ing life.
US4946998 discloses a kind of rhodium, ruthenium mixed catalyst of adopting the diaminodiphenyl-methane that contains impurity has been carried out the hydrogenant method; Its objective is; Through using the high reactivity rhodium catalyst, can under relatively mild condition, prepare the lower diamino-dicyclohexyl methane of anti-trans isomer content, simultaneously; Add ruthenium catalyst and can reduce that impurity prolongs the work-ing life of rhodium catalyst to the murder by poisoning of rhodium catalyst in the raw material.
Up to now; Aspect the research that improves the diaminodiphenyl-methane hydrogenation catalyst life-span, also mainly concentrate in the research to catalyst themselves, as foregoing; Attempt to share the toxicity that impurity causes in a part of raw material through the lower catalyzer of a kind of value; Reduce toxic action with this, prolong its work-ing life, reach the purpose that reduces the catalyzer cost the high value catalyzer.
Summary of the invention
To above technological deficiency, the present invention provides a kind of new preparation 4, and 4 '-dicyclohexyl methane diisocyanate quality percentage composition is dicyclohexyl methane diisocyanate isomer mixture and the intermediates preparation thereof of 48%-100%.The method of the invention comprises:
A) with 4; 4 '-diaminodiphenyl-methane quality percentage composition is the diaminodiphenyl-methane isomer mixture of 48%-100%; In organic solvent, reacting under the hydrogen pressure of 90 ℃-200 ℃ temperature of reaction, 3.0-12.0MPa and under the effect of catalyzer; Obtain 4,4 '-diamino-dicyclohexyl methane quality percentage composition is the diamino-dicyclohexyl methane isomer mixture of 48%-100%;
B) step a) gained diamino-dicyclohexyl methane isomer mixture and phosgene being heated to 300-500 ℃ respectively gasifies; Send into then and mix in the reactor drum that has mixing device and react; Remove hydrogenchloride, phosgene, also distillation afterwards; Obtain 4,4 '-dicyclohexyl methane diisocyanate quality percentage composition is the dicyclohexyl methane diisocyanate of 48%-100%.
Among the preparation method of the present invention, the mass percentage concentration of diaminodiphenyl-methane in organic solvent is 10-70wt% in the said step a), and the present invention further is preferably 30-60wt%.Wherein, said organic solvent is one or more in hexanaphthene, dioxane, THF, hexahydroaniline, dicyclohexyl amine, Virahol, propyl carbinol, 2-butanols and the hexahydrotoluene.
In the inventive method; Catalyzer in the said step a) is rhodium or ruthenium loaded catalyst; The carrier of said rhodium or ruthenium loaded catalyst is rare earth, zeyssatite, aluminum oxide, gac, lithium aluminate, spinel, titanium oxide, silicon oxide, sieve and silica-sesquioxide or mixed metal oxide; Wherein, the weight percent that rhodium or ruthenium account for carrier is 0.5-8%, is preferably 2-5%; Among the present invention, the consumption of rhodium catalyst is the 0.1-10% of the weight of diaminodiphenyl-methane consumption, is preferably 1-5%; The consumption of ruthenium catalyst is the 0.01-20% of the weight of diaminodiphenyl-methane consumption, is preferably 0.05-10%.
Among the preparation method of the present invention; The hydrogenation of diaminodiphenyl-methane can be batch technology in the step a); Catalyzer can recycle in a plurality of batches hydrogenation process, as, when rhodium or ruthenium loaded catalyst are in high reactivity; Adopt 4,4 '-diaminodiphenyl-methane physique amount percentage composition is that the diaminodiphenyl-methane isomer mixture of 99-100% is as starting raw material; When rhodium or ruthenium loaded catalyst are active reduce after, adopt 4,4 '-diaminodiphenyl-methane physique amount percentage composition is that the diaminodiphenyl-methane isomer mixture of 48-55% is as starting raw material.
In the inventive method, the temperature of reaction in the said step a) further is preferably 150-190 ℃, hydrogen pressure and further is preferably 4.0-10.0MPa.
Among the preparation method of the present invention, in the said step b), preferably step a) gained diamino-dicyclohexyl methane isomer mixture and phosgene are heated to 330-400 ℃ respectively and gasify.
Among the preparation method of the present invention, in the said step b), with the amino mole number calculating of diamino-dicyclohexyl methane, the usage quantity of phosgene surpasses the 25%-350% of amino mole number, preferably surpasses the 50%-250% of amino mole number.
Among the preparation method of the present invention, in the said step b), mixing device is central nozzle jet type mixing tank, smoothly sprays mixing nozzle or hole jet mixer, and reactor drum is preferably tubular reactor.Wherein, in entering has the reactor drum of mixing device, carry out hybrid reaction before, the mean flow rate of diamino-dicyclohexyl methane steam is 6-150m/s, is preferably 20-100m/s; The mean flow rate of phosgene is at least 1m/s, is preferably 3-15m/s; Wherein, the flow velocity of diamino-dicyclohexyl methane steam should be 1-10 with the ratio of phosgene flow velocity: 1, be preferably 3-8: 1.In the said step b), feed-pipe internal pressure (absolute pressure) is preferably 200-3000mbar, and the top hole pressure of tubular reactor is 150-1500mbar; Reaction mixture residence time in tubular reactor is 0.5-5 second, preferred 1-2 second.
Among the preparation method of the present invention; The diamino-dicyclohexyl methane isomer mixture is diluting with preferred rare gas element or the inert solvent steam of adopting before phosgene mixes in the said step b); Wherein, Rare gas element or inert solvent consumption are 0.1-2 times of diamino-dicyclohexyl methane isomer mixture mole number, and preferred 0.2-1 doubly.Said rare gas element is nitrogen or argon gas; Inert solvent is toluene, YLENE, chlorobenzene, orthodichlorobenzene or naphthane.
Among the preparation method of the present invention, after phosgenation reaction finishes, need will cool off fast from the high-temperature gas that reaction tubes is discharged, to reduce loss with the solution of solvent or product.Final product solution obtains H through distillation again behind dehydrochlorination, phosgene and solvent
12The MDI product.
Among the preparation method of the present invention; In the said step a), 4,4 '-diaminodiphenyl-methane quality percentage composition is that all the other compositions in the diaminodiphenyl-methane isomer mixture of 48%-100% are 2; 4 '-diaminodiphenyl-methane; Said isomer mixture can be from any source that meets requirement of the present invention, but the present invention preferably adopts following method preparation, and said method comprises:
The mixture that c) will consist of the higher homologue of diaminodiphenyl-methane isomer and diamino-diphenyl diamines is sent into the distillation tower distillation, obtains diaminodiphenyl-methane isomer cut;
D) diaminodiphenyl-methane isomer cut is sent into rectifying tower and separate, obtain 2,4 '-diaminodiphenyl-methane solution and pure 4,4 '-diaminodiphenyl-methane;
E) with 4 of different mass, 4 '-diaminodiphenyl-methane and 2, the mixing of 4 '-diaminodiphenyl-methane obtains 4, and 4 '-diaminodiphenyl-methane quality percentage composition is the diaminodiphenyl-methane isomer mixture of 48%-100%.
In the inventive method; The mixture that consists of the higher homologue of diaminodiphenyl-methane isomer and diamino-diphenyl diamines in the said step c) can be from any source; Like dicyclo MDA and the mix products that encircle MDA from MDI device enrichment process more; The composition of said mixture is generally 4 of 60-70wt%, 2 of 4 '-diaminodiphenyl-methane, 3-7wt%, the higher homologue of 4 '-diaminodiphenyl-methane, 23-37wt% diamino-diphenyl diamines.
Among the preparation method of the present invention, the distillation tower in the said step c) is the conventional distillation tower in this area, and the column bottom temperature of said distillation tower is 200 ℃-280 ℃, is preferably 230 ℃-260 ℃; Tower top temperature is 200 ℃-260 ℃, is preferably 210 ℃-230 ℃; The tower internal pressure is the 0.1-10 millibar, is preferably the 1-5 millibar; The distillation tower theoretical plate number is the 1-10 piece, is preferably the 3-5 piece.
Among the preparation method of the present invention, rectifying tower is the conventional rectifying tower in this area in the said step d), and the column bottom temperature of rectifying tower of the present invention is 200 ℃-280 ℃, is preferably 230 ℃-260 ℃; Tower top temperature is 160 ℃-230 ℃, is preferably 180 ℃-200 ℃; Side line gas phase extraction temperature is 200 ℃-250 ℃, is preferably 230 ℃-250 ℃; The tower internal pressure is the 0.1-10 millibar, preferred 1-5 millibar; The rectifying tower stage number is the 2-50 piece, is preferably the 20-30 piece, and trim the top of column is preferably 40-50 than for 0-100.
In the inventive method, said distillation tower, rectifying tower are filled with sheet metal filler or mesh screen filler.
The tower tray of said distillation tower and rectifying tower can be screen tray, valve tray, bubble deck or double-pass tray; And it is favourable adopting the filler of low pressure drop; Filler can be the sheet metal filler, the mesh screen filler, and the filler type can be Sulzer BX; Sulzer CY, Sulzer Mellapak or SulzerMellapak Plus and other.Tower body and the preferred stainless steel of internals material.
In the inventive method; Said step c) and d) diaminodiphenyl-methane isomer distillation, rectification working process can for: be preheated to 140-240 ℃ from the diaminodiphenyl-methane (dicyclo MDA) of MDI device condensation operation and the mixture of polyamines (encircling MDA) through preheater more; Preferably after 210-225 ℃; Separate through entering in the distillation tower behind the falling-film evaporator again; Many ring MDA of dicyclo MDA and trace enter in the rectifying tower with gaseous form from cat head again, and all the other dicyclo MDA and many ring MDA extraction at the bottom of distill Tata turns back to MDI device condensation operation;
The gas phase of coming out from the distillation tower cat head contains usually and is lower than 3wt%, preferably is lower than 1.5wt%, more preferably contains the dicyclo MDA of the many ring MDA that are lower than 1wt%; This gas phase enters into from rectifying tower middle part with gaseous form carries out purifying in the rectifying tower, pure 4, and 4 '-diaminodiphenyl-methane takes out with the side line thief hole of gaseous form from this tower; 2, the diaminodiphenyl-methane that 4 '-diaminodiphenyl-methane content is up to 52wt% arrives in the overhead collection of this tower with the form of liquid state, wherein also contains 4,4 '-diaminodiphenyl-methane.At the tower internal recycle, a part turns back in the distillation tower liquid part through the reboiler heating at the bottom of the tower.
In the inventive method, produced quantity is the 20-70wt% of total feed weight at the bottom of the said distillation Tata, is preferably 40-50wt%; Rectifying tower side line produced quantity is the 20-70wt% of total feed weight, is preferably 55-45wt%, and rectifying tower cat head produced quantity is the 2-10wt% of combined feed total feed material amount weight, is preferably 3-6wt%.
Preparing method of the present invention can according on the market to dicyclohexyl methane diisocyanate (H
12MDI) diversified demand of product prepares 4 in the following manner, the dicyclohexyl methane diisocyanate (H that 4 '-dicyclohexyl methane diisocyanate content is different
12MDI) product: adopt the pure 4 of step d) gained, 4 '-diaminodiphenyl-methane carries out selective catalytic hydrogenation, obtains purely 4, and 4 '-diamino-dicyclohexyl methane carries out phosgenation reaction then; Or through 4 of step e) gained, 4 '-diaminodiphenyl-methane content is that the diaminodiphenyl-methane isomer mixture of 48-100wt% carries out selective catalytic hydrogenation, carries out phosgenation reaction then; Thereby make 4, the dicyclohexyl methane diisocyanate (H that 4 '-dicyclohexyl methane diisocyanate content is different
12MDI) product;
Or through using pure 4 of different amounts; 4 '-diamino-dicyclohexyl methane and 2; 4 '-diamino-dicyclohexyl methane mixes; Carry out phosgenation reaction then, thereby make 4, the dicyclohexyl methane diisocyanate (H of the different content of 4 '-dicyclohexyl methane diisocyanate content between 48-100wt%
12MDI) product.
The present invention has reduced the murder by poisoning of impurities in raw materials to high activated catalyst owing to controlled the foreign matter content each raw material and the midbody from the source, has prolonged catalyzer work-ing life, has reduced production cost, and while the present invention has also satisfied on the market different H
12The MDI product demand, the present invention also provides the complete process flow for preparing dicyclohexyl methane diisocyanate.
Description of drawings
Fig. 1 is a diaminodiphenyl-methane separation and purification preferred embodiment process flow sheet;
Fig. 2 is preparation diamino-dicyclohexyl methane H
12MDA preferred embodiment process flow sheet;
Fig. 3 prepares dicyclohexyl methane diisocyanate preferred embodiment process flow sheet for phosgenation.
Embodiment
The present invention reaches embodiment in conjunction with the drawings and further specifies the present invention, but the present invention is not limited to this.
The process flow sheet of diaminodiphenyl-methane separation purifying technique preferred embodiment in Fig. 1 the inventive method.
The diaminodiphenyl-methane (dicyclo MDA) and polyamines (the encircling MDA) mixture 1 that come from MDI device condensation operation are preheated to 210-225 ℃ through preheater 7 more; After fully enter into distillation tower 9 after the heating through falling-film evaporator 8 again and separate; Cat head gaseous substance 3 mainly is many ring MDA that dicyclo MDA and content are lower than 3wt%; The 2 a part of extraction of bottoms material, a part circulates in tower through falling-film evaporator 8 in addition.Stage number is the 1-10 piece in the distillation tower, preferred 3-5 piece; The preferred 230-260 of column bottom temperature ℃; The preferred 210-230 of tower top temperature ℃; The preferred 1-5 millibar of tower internal pressure.
Distillation tower cat head gaseous substance 3 enters into the middle part of rectifying tower 11 with gaseous form, and is pure 4,4 '-diaminodiphenyl-methane 5 from the rectifying tower middle part with the gas phase form through condensing surface 14 cooling back extraction; Contain 2, the streams 6 of 4 '-diaminodiphenyl-methane content about 40% enters into storage tank 13 back extraction after cooling off through overhead condenser 12, and other non-condensable gas enters into vacuum system; Streams 4 parts that contain micro-heavy constituent turn back in the distillation Tata, and another part enters into rectifying tower 11 internal recycle through tower bottom reboiler 10.The preferred 230-260 of rectifying tower column bottom temperature ℃; The preferred 180-200 of tower top temperature ℃; Preferred 230-250 ℃ of side line gas phase extraction; The preferred 1-5 millibar of tower internal pressure.The preferred 20-30 piece of rectifying tower stage number, trim the top of column is than preferred 40-50; The side line produced quantity is the 40-50wt% of total feed; Produced quantity is the 40-50wt of total feed at the bottom of the tower.
Fig. 2 prepares a preferred embodiment process flow sheet of diamino-dicyclohexyl methane for diaminodiphenyl-methane shortening in the inventive method.
Diaminodiphenyl-methane raw material 15, organic solvent 16, catalyzer 17 from the MDA separation circuit join high pressure stirred autoclave 20.Use air or other rare gas elementes in nitrogen 18, hydrogen 19 replacement reaction kettles respectively.Capping still 20; In still, feed hydrogen 19 to reaction pressure; And material in the still is warming up to temperature of reaction, and keep hydrogen pressure and temperature of reaction condition in the reaction kettle, two phenyl ring of diaminodiphenyl-methane are hydrogenated to the reaction of pair six-rings with this understanding; Behind two complete hydrogenation of phenyl ring quilt, gained reaction solution 21 is mainly the mixture of diamino-dicyclohexyl methane, solvent and solid catalyst.
After reaction finishes,, the still internal pressure is let out to normal pressure 21 coolings of the reaction solution in the reaction kettle 20; With the residual hydrogen in the nitrogen 18 displacement stills, then, keep the interior nitrogen pressure of still at pressure-fired; Adopt filtering method, reaction solution in the still and solid catalyst are separated.Reaction solution 21 is under the effect of pressure-fired; Through porous filter 22, the solid catalyzer is trapped, and the cleaner liquid that sees through porous medium is mainly the solution of diamino-dicyclohexyl methane; Be called mother liquor 23; Behind the mother liquor 23 separated purifying, obtain the diamino-dicyclohexyl methane product, isolated solvent can reuse.
After the filtration of reaction solution 21 is accomplished; Porous filter 22 is carried out back flushing; With malleation nitrogen 18 solvent 16 is filtered to a side of holding back catalyzer from cleaner liquid one side pressure of porous medium, made solid catalyzer and organic solvent become suspension-s 24, and flow back to reaction kettle 20.Like this, catalyzer can be used for the hydrogenation of the diaminodiphenyl-methane of next batch.
When reaction kettle was replaced, the pressure of nitrogen, hydrogen can be controlled at 0.1-1.0MPa; During hydrogenation, the pressure of hydrogen can be controlled at 3.0-12.0MPa, preferred 4.0-10.0MPa, and temperature of reaction can be controlled at 90-200 ℃, preferred 150-190 ℃.
During hydrogenation; Diaminodiphenyl-methane is dissolved in the solvent; Solvent is selected from hexanaphthene, dioxane, THF, hexahydroaniline, dicyclohexyl amine, Virahol, propyl carbinol, 2-butanols, hexahydrotoluene, can select one or more mixture wherein for use, preferred THF.The mass concentration of diaminodiphenyl-methane in solution is 10-70wt%, preferred 30-60wt%.
Catalyzer can be selected rhodium or ruthenium loaded catalyst respectively for use; Perhaps select rhodium, the blending of ruthenium loaded catalyst for use; Rhodium, ruthenium are carried on the carrier of aluminum oxide, gac, lithium aluminate, spinel, titanium oxide, silicon oxide, sieve and silica-sesquioxide, mixed metal oxide in proportion; Rhodium, ruthenium account for the weight percent of carrier for being respectively 0.5-8%, preferred 2-5wt%.The weight percent that rhodium catalyst accounts for the diaminodiphenyl-methane consumption is 0.1-10wt%, preferred 1-5wt%, and the weight percent that ruthenium catalyst accounts for the MDA consumption is the preferred 0.05-10wt% of 0.01-20wt%.
The filtration medium of porous filter can be selected filtering net, filtering membrane, metal sintering rod, metal sintering net etc. for use, and material can be selected stainless steel or synthetic materials for use, when selecting synthetic materials for use, consider whether solvent can cause corrosion to filtration medium.During reacting liquid filtering, the temperature in the reaction kettle can be controlled at 30-60 ℃, preferred 40-50 ℃.During the back flushing of reacting liquid filtering and strainer; Remove because after the pressure drop that the strainer installation causes; Nitrogen pressure can be controlled at 1.0-8.0MPa, can consider that in addition additionaling power filters and the operation of back flushing, such as adopting the form of adding transferpump.
Fig. 3 prepares the process flow sheet of a preferred embodiment of dicyclohexyl methane diisocyanate for phosgenation.
At first, diamino-dicyclohexyl methane (H
12MDA) 25 with nitrogen 26 through mix laggard go into to be preheated to temperature of reaction to interchanger 33 enter into the reactor drum 35 that has mixing tank; Enter in the reactor drum 35 after 34 preheatings of phosgene 27 process interchanger simultaneously; In reactor drum 35 phosgene with; The diamino-dicyclohexyl methane steam enters into the tourie 37 that the top has filler after cooling off fast through solvent or the solution 29 that contains product flash cooler 36 in through thorough mixing, reaction back gained high temperature gas-phase product 28; The extraction of a products therefrom solution part enters into subsequent processing; A part is converged in the quick cooling that fresh solvent 31 participates in high temperature gas-phase product 28 and is gone, and partial solvent and product that wherein gas phase is carried secretly in the tourie 37 flow to condensing surface 38 under normal pressure, and non-condensable gas further gets into HCl, COCl
2Retrieving arrangement 32.Products therefrom solution can obtain pure H through general phosgene, the HCl of removing behind desolventizing and the distillation process
12The MDI product.Said flash cooler can be the rotary jet or the multiple nozzle spraying device of Venturi type, belt length pipe; And the progression of injector can be single-stage or multistage; Preferably in the injector outlet conduit, static mixer is set, the enhancing of injector assimilation effect is not limited to above-mentioned several kinds of forms.
Before carrying out phosgenation reaction; The preferable preheating temperature of raw material is 330 ℃-400 ℃;, the diamino-dicyclohexyl methane steam is generally used rare gas element such as nitrogen and argon gas, or with the vapor dilution of inert solvent such as toluene, YLENE, chlorobenzene, orthodichlorobenzene, naphthane; Amino mole number with diamino-dicyclohexyl methane calculates, and the excessive 25%-350% of phosgene is preferably 50%-250%, and rare gas element or inert solvent consumption are generally 0.1-2 times of amino mole number, and preferred 0.2-1.0 times, the preferred 1-2s of intraductal retention time.
When carrying out phosgenation reaction, feed-pipe internal pressure (absolute pressure) is preferably 200-3000mbar, and the reaction tubes top hole pressure of reactor drum is preferably 150-1500mbar.Phosgene flows flow velocity 1m/s at least before mixing, preferred 3-15m/s, and diamino-dicyclohexyl methane steam nozzle exit flow velocity is generally 6-150m/s, preferred 20-100m/s.
4,4 ' and 2, the separation preparation of 4 '-diaminodiphenyl-methane
Embodiment 1
Adopt flow process shown in Figure 1; The dicyclo MDA that comes from diphenylmethanediisocyanate (MDI) device condensation operation fully is preheated to and enters into the distillation tower that diameter is 50mm after 220 ℃ through preheater, falling-film evaporator with many ring MDA; This tower is filled with corrugated regular filler; Stage number is 5, and bottom temp is 250 ℃, and head temperature is that 230 ℃ and tower top pressure are 3.5 millibars; Feed composition is 4,4 '-diaminodiphenyl-methane content 68wt%, and 2,4 '-diaminodiphenyl-methane content 5wt% encircles MDA more and is about 27wt%.Distillation tower cat head gaseous substance enters into the rectifying tower middle part.The rectifying tower column bottom temperature is 244 ℃, and tower top temperature is 190 ℃, and side line gas phase extraction temperature is 240 ℃ in the tower, and the rectifying tower stage number is 25.
In whole distillation, distillation system, the inlet amount of charging 1 is 2.7kg/h, and rectifying tower side line produced quantity is 1.25kg/h, and produced quantity is 1.3kg/h at the bottom of the distillation Tata, and rectifying tower cat head produced quantity is 0.15kg/h.Gas chromatographic analysis is the result show, gained 4, and 4 '-diaminodiphenyl-methane purity is 99.7wt%; Cat head extraction material moderate purity is 99.5wt%, wherein 2, and 4 '-diaminodiphenyl-methane content is 50wt%; 4,4 '-diaminodiphenyl-methane content is 49.5wt%.Rectifying is resulting 2,4 '-diaminodiphenyl-methane and 4, and 4 '-diaminodiphenyl-methane can be allocated arbitrarily and obtain 4, and 4 '-diaminodiphenyl-methane content is the dicyclo MDA of 48-100wt% content.
The preparation of diamino-dicyclohexyl methane
Embodiment 2
Adopt flow process shown in Figure 2,4,4 '-diaminodiphenyl-methane content is that diaminodiphenyl-methane and the THF of 99.7wt% joins in the high pressure stirring tank with 1: 1 mass ratio, with the Rh/Al of 3wt%
2O
3Catalyzer joins in the still, and the catalyzer add-on accounts for the 1.2wt% of diaminodiphenyl-methane charging capacity.After carrying out nitrogen, hydrogen exchange in the reaction kettle, in reaction kettle, charge into hydrogen to 5MPa, material in reactor is warming up to 185 ℃; Keep this temperature, and the hydrogen pressure in the still is maintained 5MPa, kept 240 minutes; Be cooled to 40 ℃, and the pressure release displacement, still internal reaction liquid is filtered; Be trapped the solid catalyzer and pour the hydrogenation reaction that continues to serve as next batch in the reaction kettle through backwash operation, the cleaner liquid main ingredient is the tetrahydrofuran solution of diamino-dicyclohexyl methane.Get cleaner liquid appearance and carry out gas chromatographic analysis, diaminodiphenyl-methane content is 0.12wt%, and diamino-dicyclohexyl methane content is 86.57wt%.
Embodiment 3
Adopt flow process shown in Figure 2; 4; 4 '-diaminodiphenyl-methane content is that diaminodiphenyl-methane isomer mixture and the hexahydroaniline of 50.12wt% joins in the high pressure stirring tank with 3: 10 mass ratio; The Ru/C catalyzer of 5wt% is joined in the still, and the catalyzer add-on accounts for the 5wt% of diaminodiphenyl-methane charging capacity.After carrying out nitrogen, hydrogen exchange in the reaction kettle, in reaction kettle, charge into hydrogen to 9MPa, material in reactor is warming up to 180 ℃; Keep this temperature, and the hydrogen pressure in the still is maintained 9MPa, kept 360 minutes; After cooling is filtered; Get cleaner liquid appearance and carry out gas chromatographic analysis, diaminodiphenyl-methane content is 2.36wt%, and diamino-dicyclohexyl methane content is 91.75wt%.
Embodiment 4
Adopt flow process shown in Figure 2,4,4 '-diaminodiphenyl-methane body burden is that diaminodiphenyl-methane isomer mixture and the THF of 85wt% joins in the high pressure stirring tank with 1: 1 mass ratio, with the Rh/Al of 5wt%
2O
3, 5wt%Ru/Al
2O
3Join after the catalyst mix in the still, the catalyzer add-on accounts for the diaminodiphenyl-methane charging capacity and is respectively 3wt%, 1wt%.After carrying out nitrogen, hydrogen exchange in the reaction kettle, in reaction kettle, charge into hydrogen to 6MPa, material in reactor is warming up to 170 ℃; Keep this temperature, and the hydrogen pressure in the still is maintained 6MPa, keep certain reaction times; Cooling is got cleaner liquid appearance and is carried out gas chromatographic analysis after filtering, and the catalyzer that filtration is trapped washes back in the high pressure stirring tank with THF; Carry out hydrogenation reaction by the aforesaid operations circulation, each batch reaction times and cleaner liquid analytical results are seen table 1.
Table 14,4 '-diaminodiphenyl-methane content are the diaminodiphenyl-methane hydrogenation of 85wt%
| Batch | Reaction times (minute) | Diamino-dicyclohexyl methane content (wt%) | Diaminodiphenyl-methane content (wt%) |
| 1 | 180 | 90.06 | 0.03 |
| 2 | 150 | 89.87 | 0.11 |
| 3 | 147 | 90.26 | 0.09 |
| 4 | 153 | 90.15 | 0.13 |
| 5 | 159 | 89.67 | 0.20 |
| 6 | 168 | 89.14 | 0.23 |
| 7 | 170 | 89.56 | 0.22 |
| 8 | 243 | 89.22 | 0.30 |
| 9 | 245 | 87.73 | 0.71 |
| 10 | 391 | 85.65 | 1.84 |
| 11 | 480 | 83.72 | 3.52 |
| 12 | 570 | 81.99 | 5.03 |
| 13 | 660 | 81.76 | 5.30 |
Catalyzer is applied mechanically 13 batches altogether, and the reaction times increased to 11 hours by 3 hours, and unconverted raw material surpassed 1wt% from the 10th batch, shows the decline fast of catalyst activity and hydrogenation efficiency.
Embodiment 5
Adopt flow process shown in Figure 2, catalyzer is selected the Rh/Al of the 5wt% identical with embodiment 4
2O
3, 5wt%Ru/Al
2O
3Catalyzer; Carry out the recycled experiment of catalyzer by the operation among the embodiment 4,1-18 batch, select 4 for use; 4 '-diaminodiphenyl-methane (is called for short: 4; 4 bodies) content be the diaminodiphenyl-methane isomer mixture of 99-100wt% as starting raw material, select 4 for use for 19-27 batch, 4 '-diaminodiphenyl-methane content is that the diaminodiphenyl-methane isomer mixture of 49-51wt% is as starting raw material; Diaminodiphenyl-methane, THF, catalyzer charging capacity are identical with embodiment 4; Temperature, the pressure condition of reaction are identical with embodiment 4, and each batch keeps the certain reaction time, and table 2 is the reaction times of taking from part batch and the result of cleaner liquid analysis.
Table 2
| Batch | 4,4 ' body burden (wt%) | Reaction times (minute) | Diamino-dicyclohexyl methane content (wt%) | Diaminodiphenyl-methane content (wt%) |
| 1 | 99.6 | 140 | 92.06 | 0.05 |
| 5 | 99.6 | 98 | 91.58 | 0.15 |
| 10 | 99.6 | 96 | 91.67 | 0.17 |
| 13 | 99.7 | 100 | 91.46 | 0.11 |
| 15 | 99.6 | 117 | 92.01 | 0.20 |
| 16 | 99.7 | 150 | 91.67 | 0.19 |
| 18 | 99.6 | 153 | 92.36 | 0.23 |
| 19 | 50.1 | 240 | 90.55 | 0.17 |
| 21 | 50.2 | 242 | 90.03 | 0.31 |
| 23 | 50.0 | 247 | 89.64 | 0.38 |
| 25 | 50.1 | 314 | 88.98 | 1.03 |
| 27 | 50.2 | 480 | 88.36 | 2.83 |
Catalyzer is applied mechanically 27 batches altogether, and the reaction times increased to 8 hours by 140 minutes, and unconverted raw material just surpasses 1wt% from the 25th batch, and content is lower than embodiment 4, shows that the speed that catalyst activity reduces is lower than embodiment 4.End to the 27th batch, the recycled number of times of catalyzer has increased by 107% than embodiment 4.
Embodiment 6
Among the embodiment 5 in 1st batch of diamino-dicyclohexyl methane that makes 4; 4 '-diamino-dicyclohexyl methane content is 99.7wt%; In 19th batch of diamino-dicyclohexyl methane that makes 4,4 '-diamino-dicyclohexyl methane content is 50.1wt%, and its mass ratio by 7: 3 is carried out blending; In the gained diamino-dicyclohexyl methane 4,4 '-diamino-dicyclohexyl methane content is 84.8wt% after the blending.
The result of embodiment 6 shows, through the blending of gained diamino-dicyclohexyl methane among the embodiment 5, can obtain the consistent product of content of isomer and embodiment 4.
Add the blending operation of embodiment 6 according to the hydroprocessing of embodiment 5; Can obtain the product identical with embodiment 4; And can realize that catalyst recirculation applies mechanically number of times and increase by 107% effect than embodiment 4; In process of production, according to such schedule of operation, can effectively reduce production cost.
The preparation of dicyclohexyl methane diisocyanate
Embodiment 7
Adopt flow process shown in Figure 3, adopt above-mentioned hydrogenation gained diamino-dicyclohexyl methane (H
12MDA), phosgene and nitrogen with 1: 4: 1 mol ratio respectively via separately interchanger continuously in the inflow reactor.Reactor downstream is connected with gas injection absorption unit (being used for condensation) and excess phosgene and hydrogen chloride absorption tower.H
12MDA, phosgene and nitrogen are heated to 360 ℃ respectively in advance before entering into reactor drum as shown in Figure 3.H
12The MDA steam is used with respect to H
12The nitrogen dilution that MDA steam mole number is 1 times and form mixture enters into then and enters into reaction tubes after mixing in the single nozzle central jet mixing tank and react H
12MDA steam and nitrogen are walked nozzle, and phosgene is walked the mixer chamber body portion, and the long-pending area ratio with mixer cavity in nozzle throat area is 1: 15 in the mixing tank, and tube inner diameter is 15mm, and the reaction tubes internal pressure is 600 millibars, the H of the jet exit of wherein flowing through
12The flow velocity of the mixture of MDA steam and nitrogen is about 28m/s, and the phosgene flow velocity is about 5m/s before mixing in the mixing tank.After in reaction tubes, stopping about 1.3s, reaction product H
12MDI is with the H of 120 ℃ orthodichlorobenzene
12MDI solution is quickly cooled to 140 ℃-150 ℃ through the gas injection absorption unit and obtains photochemical liquid, shows dicyclohexyl methane diisocyanate (H in the photochemical liquid through gas chromatographic analysis
12MDI) content is 99.08% (gas phase normalization method), H
12The MDI yield is H
1297.6% of MDI theoretical yield.
Claims (28)
1. a method for preparing dicyclohexyl methane diisocyanate is characterized in that, said method comprises:
A) with 4; 4 '-diaminodiphenyl-methane quality percentage composition is more than or equal to 48% but less than 100% diaminodiphenyl-methane isomer mixture; In organic solvent, reacting under the hydrogen pressure of 90 ℃-200 ℃ temperature of reaction, 3.0-12.0MPa and under the effect of catalyzer; Obtain 4,4 '-diamino-dicyclohexyl methane quality percentage composition is more than or equal to 48% but less than 100% diamino-dicyclohexyl methane isomer mixture;
B) step a) gained diamino-dicyclohexyl methane isomer mixture and phosgene being heated to 300-500 ℃ respectively gasifies; Send into then and mix in the reactor drum that has mixing device and react; Remove hydrogenchloride, phosgene, also distillation afterwards; Obtain 4,4 '-dicyclohexyl methane diisocyanate quality percentage composition is more than or equal to 48% but less than 100% dicyclohexyl methane diisocyanate;
In the said step a), 4,4 '-diaminodiphenyl-methane quality percentage composition is more than or equal to 48% but adopt following method preparation less than 100% diaminodiphenyl-methane isomer mixture:
The mixture that c) will consist of the higher homologue of diaminodiphenyl-methane isomer and diamino-diphenyl diamines is sent into the distillation tower distillation, obtains diaminodiphenyl-methane isomer cut;
D) diaminodiphenyl-methane isomer cut is sent into rectifying tower and separate, obtain 2,4 '-diaminodiphenyl-methane solution and pure 4,4 '-diaminodiphenyl-methane;
E) with 4 of different mass, 4 '-diaminodiphenyl-methane and 2,4 '-diaminodiphenyl-methane mix and to obtain 4, and 4 '-diaminodiphenyl-methane quality percentage composition is more than or equal to 48% but less than 100% diaminodiphenyl-methane isomer mixture.
2. method according to claim 1 is characterized in that, the mass percentage concentration of diaminodiphenyl-methane in organic solvent is 10-70wt% in the said step a).
3. method according to claim 2 is characterized in that, the mass percentage concentration of diaminodiphenyl-methane in organic solvent is 30-60wt% in the said step a).
4. method according to claim 2 is characterized in that, organic solvent is one or more in hexanaphthene, dioxane, THF, hexahydroaniline, dicyclohexyl amine, Virahol, propyl carbinol, 2-butanols and the hexahydrotoluene in the said step a).
5. method according to claim 4 is characterized in that, the catalyzer in the said step a) is rhodium or ruthenium loaded catalyst.
6. method according to claim 5; It is characterized in that; The carrier of rhodium or ruthenium loaded catalyst is rare earth, zeyssatite, aluminum oxide, gac, lithium aluminate, spinel, titanium oxide, silicon oxide, sieve and silica-sesquioxide or mixed metal oxide in the said step a); Wherein, to account for the weight percent of carrier be 0.5-8% for rhodium or ruthenium.
7. method according to claim 6 is characterized in that, wherein, the weight percent that rhodium or ruthenium account for carrier is 2-5%.
8. method according to claim 6 is characterized in that, the consumption of rhodium catalyst is the 0.1-10% of the weight of diaminodiphenyl-methane consumption in the said step a); The consumption of ruthenium catalyst is the 0.01-20% of the weight of diaminodiphenyl-methane consumption.
9. method according to claim 8 is characterized in that, the consumption of rhodium catalyst is the 1-5% of the weight of diaminodiphenyl-methane consumption in the said step a); The consumption of ruthenium catalyst is the 0.05-10% of the weight of diaminodiphenyl-methane consumption.
10. method according to claim 8 is characterized in that, temperature of reaction is that 150-190 ℃, hydrogen pressure are 4.0-10.0MPa in the said step a).
11. method according to claim 10 is characterized in that, in the said step b), step a) gained diamino-dicyclohexyl methane isomer mixture and phosgene is heated to 330-400 ℃ respectively gasifies.
12. method according to claim 11 is characterized in that, in the said step b), with the amino mole number calculating of diamino-dicyclohexyl methane, the usage quantity of phosgene surpasses the 25%-350% of amino mole number.
13. method according to claim 12 is characterized in that, in the said step b), with the amino mole number calculating of diamino-dicyclohexyl methane, the usage quantity of phosgene surpasses the 50%-250% of amino mole number.
14. method according to claim 12 is characterized in that, in the said step b), mixing device is central nozzle jet type mixing tank, smoothly sprays mixing nozzle or hole jet mixer; Reactor drum is a tubular reactor.
15. method according to claim 14 is characterized in that, in the said step b), in entering has the reactor drum of mixing device, carry out hybrid reaction before, the mean flow rate of diamino-dicyclohexyl methane steam is 6-150m/s; The mean flow rate of phosgene is 3-15m/s; Wherein, the flow velocity of diamino-dicyclohexyl methane steam is 1-10 with the ratio of phosgene flow velocity: 1.
16. method according to claim 15 is characterized in that, the mean flow rate of diamino-dicyclohexyl methane steam is 20-100m/s; Wherein, the flow velocity of diamino-dicyclohexyl methane steam is 3-8 with the ratio of phosgene flow velocity: 1.
17. method according to claim 15 is characterized in that, in the said step b), the absolute pressure in the feed-pipe is 200-3000mbar; The top hole pressure of tubular reactor is 150-1500mbar; Reaction mixture residence time in tubular reactor is 0.5-5 second.
18. method according to claim 17 is characterized in that, reaction mixture residence time in tubular reactor is 1-2 second.
19. method according to claim 17; It is characterized in that; In the said step b); The diamino-dicyclohexyl methane isomer mixture with dilute with rare gas element or inert solvent steam before phosgene mixes, wherein, the consumption of rare gas element or inert solvent be diamino-dicyclohexyl methane isomer mixture mole number 0.1-2 doubly.
20. method according to claim 19 is characterized in that, the consumption of rare gas element or inert solvent is 0.2-1 a times of diamino-dicyclohexyl methane isomer mixture mole number.
21. method according to claim 19 is characterized in that, in the said step b), rare gas element is nitrogen or argon gas; Inert solvent is toluene, YLENE, chlorobenzene, orthodichlorobenzene or naphthane.
22. method according to claim 1 is characterized in that, the distillation tower column bottom temperature is 200 ℃-280 ℃ in the said step c); Tower top temperature is 200 ℃-260 ℃; The tower internal pressure is the 0.1-10 millibar; The distillation tower theoretical plate number is the 1-10 piece.
23. method according to claim 22 is characterized in that, the distillation tower column bottom temperature is 230 ℃-260 ℃ in the said step c); Tower top temperature is 210 ℃-230 ℃; The tower internal pressure is the 1-5 millibar; The distillation tower theoretical plate number is the 3-5 piece.
24. method according to claim 22 is characterized in that, the rectifying tower column bottom temperature is 200 ℃-280 ℃ in the said step d); Tower top temperature is 160-230 ℃; Side line gas phase extraction temperature is 200-250 ℃; The tower internal pressure is the 0.1-10 millibar; The rectifying tower stage number is the 2-50 piece, and trim the top of column is than being 0-100.
25. method according to claim 24 is characterized in that, the rectifying tower column bottom temperature is 230-260 ℃ in the said step d); Tower top temperature is 180-200 ℃; Side line gas phase extraction temperature is 230-250 ℃; The tower internal pressure is the 1-5 millibar; The rectifying tower stage number is the 20-30 piece, and trim the top of column is than being 40-50.
26. method according to claim 24 is characterized in that, in the said step c) distillation Tata at the bottom of produced quantity be the 20-70wt% of total feed; Rectifying tower side line produced quantity is the 20-70wt% of total feed in the step d), and rectifying tower cat head produced quantity is the 2-10wt% of combined feed total feed material amount.
27. method according to claim 26 is characterized in that, in the said step c) distillation Tata at the bottom of produced quantity be the 40-50wt% of total feed; Rectifying tower side line produced quantity is the 55-45wt% of total feed in the step d), and rectifying tower cat head produced quantity is the 3-6wt% of combined feed total feed material amount.
28. want 26 described methods, it is characterized in that said distillation tower, rectifying tower are filled with sheet metal filler or mesh screen filler according to right.
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| CN103553969B (en) * | 2010-12-23 | 2015-05-27 | 浙江丽水有邦新材料有限公司 | Preparation method of 4,4'-dicyclohexylmethane diisocyanate |
| CN102093259A (en) * | 2010-12-23 | 2011-06-15 | 浙江丽水有邦化工有限公司 | Method for preparing 4,4'-dicyclohexyl methane diisocyanate |
| CN102093227B (en) | 2011-01-07 | 2013-08-07 | 烟台万华聚氨酯股份有限公司 | Method for producing 4,4'-diamino dicyclohexyl methane with low trans-trans isomer content |
| CN103319372B (en) * | 2012-03-19 | 2014-11-05 | 万华化学集团股份有限公司 | Method for producing light colored dicyclohexyl methane diisocyanate |
| CN103265438B (en) | 2013-05-22 | 2014-11-05 | 万华化学集团股份有限公司 | Method for preparing diaminodicyclohexyl methane |
| JP6621760B2 (en) * | 2014-03-27 | 2019-12-18 | コベストロ、ドイチュラント、アクチエンゲゼルシャフトＣｏｖｅｓｔｒｏ Ｄｅｕｔｓｃｈｌａｎｄ Ａｇ | Operation method of gas phase phosgenation plant |
| CN111807967B (en) * | 2020-07-08 | 2024-01-09 | 西安近代化学研究所 | Preparation method of methylcyclohexanetriamine and methylcyclohexanetriiso (thio) cyanate |
| CN111848475B (en) * | 2020-07-08 | 2022-05-24 | 西安近代化学研究所 | Preparation method of cyclohexyltriamine and preparation method of cyclohexyl triisocyanate |
| CN114380715A (en) * | 2022-01-24 | 2022-04-22 | 纳琳威纳米科技（上海）有限公司 | Preparation method of hydrogenated phenylmethane diisocyanate |
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