CN101580509B - Method for producing electronic-grade pyromellitic dianhydride from secondary trapped coarse anhydride - Google Patents
Method for producing electronic-grade pyromellitic dianhydride from secondary trapped coarse anhydride Download PDFInfo
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Abstract
The invention relates to a method for producing electronic-grade pyromellitic dianhydride from secondary trapped coarse anhydride, which belongs to the technical field of preparing pyromellitic dianhydride. The method comprises the following steps: secondary trapped coarse anhydride washing; dehydration and decoloration; recrystallization; and drying. The method has the following advantages: firstly, the process flow is simple and short so that energy sources can be saved; secondly, because the refining process is performed in a closed device, the environment is not damaged; thirdly, because the separated out crystallization mother solution can be recycled, not only the yield of the PMDA can be improved and the dosages of a dehydrating agent and a discoloring agent are saved to embody the economical efficiency, but also the energy consumption is saved; fourthly, the purity of the obtained PMDA can reach over 99 percent; and fifth, the PMDA produced by the method can reach the purity grade requirement of synthesizing an electronic-grade PI film.
Description
Technical field
The invention belongs to the preparing technical field of pyromellitic acid anhydride, be specifically related to a kind ofly catch the method that thick acid anhydride is produced the electronic-grade pyromellitic acid anhydride by two.
Background technology
The English name of pyromellitic acid anhydride is that Pyromellitic Dianhydride (is abbreviated as: PMDA, as follows), the PMDA that will synthesize the purity requirement height (metal ion content among the PMDA is below 2ppm) that high-end electronic-grade polyimide (Polyimide, abbreviation PI) film uses usually is called electronic-grade PMDA.
Two to catch thick acid anhydride be the product that is captured through secondary by the crude product pyromellitic acid anhydride that durol generates through catalytic gas phase oxidation, its main component is PMDA, and light constituent is respectively Tetra hydro Phthalic anhydride (PA), trimellitic acid 1,2-anhydride (TMA), Pyromellitic Acid (PMA), Pyromellitic Acid list acid anhydride (PMMA) and inclined to one side three acid anhydrides of 5-methyl (MTMA).Relative one catches thick acid anhydride, its light constituent PA and TMA content height (about 15-50%), and PMDA content is low, also contains PMA and the mechanical impurity and the ultra-fine foreign material of a small amount of (1-3%).Owing to use catalyzer difference, particularly technology different with catching apparatus, two to catch the purity of thick acid anhydride widely different, and therefore, the two process for purification need of catching thick acid anhydride be selected corresponding process for purification according to two differences of catching thick anhydride component.
Abroad low levels (containing PMDA in the raw material is 92.6-96.9%) PMDA purified document is had: the clear 61-215352 of JPK, contain in the thick acid anhydride PMDA92.6%, TMA4.6%, other 2.8%, with solvent benzol first cyanogen under 150 ℃ with its dissolving after be cooled to room temperature again, filtration drying, pyromellitic acid anhydride yield 95%, purity 99%, TMA 0.7%, other 0.3%, acid number 1024KOH/g; The clear 50-58024 of JPK contains PMDA 96.9% in the raw material, use solvent ether, and solvent and material rate are 2: 1, room temperature treatment 1 hour, yield 96%, purity 99.9%, acid number 1029 KOH/g; The clear 45-4052 of JPK, contain PMDA 95% in the raw material, using solvent is that dioxane and acetic anhydride mixed by 10: 1 as mixed solvent, mixed solvent and raw material were by 5: 1 (weight), extracting is 3 hours under 210 ℃ of oil baths, 0.8mmHg high vacuum, yield 95%, purity 99.8%, 162 ± 3 ℃ of extractum (TMA) fusing points.
The manufacturer of the PMDA of China's production at present is more, used method mainly contains following two kinds, be hydrolysis method and sublimation purifying method: with regard to the former hydrolysis method, because the employed solvent of hydrolysis method is generally tap water, metal ion (K, Na, Ca, Fe, Al, Zn, Po etc.) contained in the water is more, metal ion content in the finished product (PMDA after PMA or the dehydration) is considerably beyond 10ppm, can't reach below the 2ppm, so product can only use in the production of low-grade powder coating or low-grade Kapton.In addition, hydrolysis method is produced PMA, and two weight ratios of catching thick acid anhydride and solvent (water) are 1: 8-10, and need hydrolysis 3-4 time, and can produce a large amount of acid waste waters, environment is caused negative impact; With regard to the latter's subliming method method for refining, though products obtained therefrom purity improves a lot and has removed metal ion, but still contain more organic impurity, thereby still can only be applicable in the production, low-grade powder coating or in, low-grade PI film, can not satisfy the demand of foreign vendor to high-quality PMDA product.In addition, subliming method also exists complicated operation, labor strength is big, and environment is abominable, seriously polluted, many drawbacks such as yield low (only 50～70%) and energy consumption height.
Except that above-mentioned two kinds of methods, also have hot gas flow to carry method and solvent method, though Rifinement of pyromellitic acid dianhydride by hot air carrying process early has bibliographical information, Chinese invention patent for example, the patent No.: ZL95104479.6, but still being in the exploratory stage, technology is immature and yield is low, is difficult to realize suitability for industrialized production.Therefore, up to now, there is not manufacturer to attempt; The refining PMDA of solvent method also is in the exploratory stage at present, thereby does not hear the report that production firm's success is arranged equally.
In a word, it is more that at present China produces the producer of crude product PMDA, and production technique and major equipment are roughly the same, and especially: the capture of oxide compound is three-stage trapping.Thick acid anhydride (one the catches thick acid anhydride) purity that one-level captures is higher relatively, and all more than 98%, and the purity of the thick acid anhydride (two catch thick acid anhydride) that secondary captures is lower, only is 50-80%, and the purity of the thick acid anhydride of three-stage trapping (three catch thick acid anhydride) is extremely low, is about 10-35%.For using two to catch thick acid anhydride production high purity and even be the PMDA of electron pole, owing at present do not have good method all the time, thereby adopt repeatedly hydrolysis removal light constituent, direct production PMA usually; The PMA that perhaps incites somebody to action repeatedly hydrolysis and obtain carries out sublimation purifying and becomes PMDA.Thisly catch thick acid anhydride by two and produce the methods of PMDA and not only have the shortcoming of aforesaid hydrolysis method, but also be attended by the deficiency of aforementioned sublimation purifying method.
Summary of the invention
Task of the present invention is to provide a kind of and catches the method that thick acid anhydride is produced the electronic-grade pyromellitic acid anhydride by two, this method can overcome hydrolysis method in the prior art and subliming method existing long such as technological process, energy consumption is big, contaminate environment and product yield and the low deficiency of purity.
Task of the present invention is finished like this, a kind ofly catches the method that thick acid anhydride is produced the electronic-grade pyromellitic acid anhydride by two, and it may further comprise the steps:
A) thick acid anhydride is caught in washing two, two solvents of catching thick acid anhydride and washing usefulness are joined vessel in heating in proportion, and postcooling carries out suction strainer after the cooling; Obtain solid materials, and filtrate is utilized after distillation again;
B) dehydration and decolorization drops into solid materials, dewatering agent and discoloring agent in the reactor in proportion, and reacting by heating adopts the foreign body filter filtered while hot after the reacting by heating, and filtrate is filtered once more behind crystallisation by cooling and obtained crystalline solid;
C) recrystallization with crystalline solid crystallisation by cooling once more in the recrystallization still, to the crystallized stock suction filtration behind the crystallisation by cooling once more, obtains containing the pyromellitic acid anhydride xln of mother liquor;
D) drying, the pyromellitic acid anhydride xln that will contain mother liquor places drying machine to carry out drying, obtains the electronic-grade pyromellitic acid anhydride, the crystalline mother solution cyclically utilizing again after cooling.
In a specific embodiment of the present invention, steps A) the two weight part proportionings of catching thick acid anhydride and solvent described in are 1: 2.5-4, described container are enamel reaction still.
The Heating temperature of the heating in another specific embodiment of the present invention, steps A) is 80-110 ℃; Described being cooled to is cooled to 28-32 ℃.
In another specific embodiment of the present invention, described two catch thick acid anhydride is meant that the quality percentage composition of pyromellitic acid anhydride is that two of 74-78% catches thick acid anhydride, and described solvent is that mass percent concentration is the acetic anhydride of 40-85%.
The weight part proportioning of solid materials, dewatering agent and the discoloring agent in another specific embodiment of the present invention, step B) is 1: 7-10: 0.01-0.03.
Go back in the specific embodiment of the present invention, described dewatering agent is that mass percent concentration is the acetic anhydride of 80-99%, and described discoloring agent is a gac.
The temperature of reaction of the reacting by heating more of the present invention and in specific embodiment, step B) is 115-125 ℃, and the reaction times is 40-90min, and described crystallisation by cooling is that filtrate with the filtered while hot gained is at 24-28 ℃ of following crystallisation by cooling.
In of the present invention and then specific embodiment, step C) crystallisation by cooling once more described in is earlier with step B) resulting crystalline solid inserts in the recrystallization still, add PMDA crystal seed and solvent and carry out crystallisation by cooling once more, temperature is risen to 110-120 ℃ again, slow cooling then is to 28-32 ℃, wherein: the weight part proportioning between crystalline solid, PMDA crystal seed and the solvent three is 1: 0.05-0.15: 2-3, described solvent are acetic anhydride.
Of the present invention again more and in specific embodiment, the time of described slow cooling is 180-240min.
In again of the present invention and then specific embodiment, step D) drying described in is vacuum-drying, and vacuum drying vacuum tightness is 0.06-0.08MPa, and drying temperature is 160-170 ℃, and be 150-240min time of drying.
One of advantage of technical scheme provided by the invention, technical process is brief, and can save energy; Two because treating process is to carry out in the device of sealing, therefore harmless to environment; Three because isolated crystalline mother solution cyclically utilizing, therefore not only can improve the yield of PMDA, save the consumption of dewatering agent and discoloring agent and use the embodiment economy, and can energy efficient; Four, the purity of the PMDA that obtains can reach more than 99%; Five, the resulting PMDA of method can reach the purity level requirement that is used for synthetic electronic-grade PI film.
Embodiment
For the auditor that the makes Patent Office especially public can fully understand technical spirit of the present invention; the applicant will be described in more detail technical scheme of the present invention with four embodiment that provide below; but embodiment is not the restriction to the present invention program; any what make according to the present invention program's inspiration only is pro forma and be not to be substantial change, so all should be considered as belonging to protection scope of the present invention.
Embodiment 1:
A) thick acid anhydride is caught in washing two, with the content of PMDA be 74.3% (being the quality percentage composition of aforesaid pyromellitic acid anhydride) two catch thick acid anhydride 120Kg, and be that 85% acetic anhydride 300Kg all joins (two weight ratios of catching thick acid anhydride and solvent are 1: 2.5) in the enamel reaction still with mass percent concentration, be heated to 110 ℃ then, then be cooled to 28 ℃, carry out suction strainer again, promptly carry out solid-liquid separation, obtain solid materials, the filtrate of solid-liquid separation gained is utilized (reuse) again after distillation;
B) dehydration and decolorization, remove mechanical impurity and ultra-fine foreign material by dehydration and decolorization, the solid materials 100Kg that obtains through solid-liquid separation specifically: will be) by steps A, as dewatering agent and mass percent concentration be 80% acetic anhydride 1000Kg and put into reacting by heating in the reactor as the gac 2Kg (three's weight part proportioning is 1: 10: 0.02) of discoloring agent, the temperature of reacting by heating is 115 ℃, reaction times is 90min, reaction finishes back foreign body filter filtered while hot, filtrate is at 24 ℃ of following crystallisation by cooling, crystallized stock is filtered, obtain crystalline solid;
C) recrystallization, will be by step B) resulting crystalline solid crystallisation by cooling once more in the recrystallization still, specifically: crystalline solid is inserted in the recrystallization still, and add PMDA crystal seed and solvent and carry out crystallisation by cooling once more, crystalline solid, PMDA crystal seed and solvent add in the recrystallization still by 1: 0.05: 2 weight ratio, promptly add crystalline solid 80Kg, PMDA crystal seed 4Kg and as solvent and mass percent concentration be 85% acetic anhydride 160Kg, treat aforesaid crystalline solid, after PMDA crystal seed and solvent add in the recrystallization still, then be heated to 114 ℃, then progressively cool off and promptly slowly be cooled to 32 ℃ with 180min, obtain once more the crystallized stock behind the crystallisation by cooling, to the crystallized stock suction filtration, obtain containing the PMDA xln of mother liquor;
D) drying, the PMDA xln that will contain mother liquor places drying machine, and dry 240min under the condition of 170 ℃ and vacuum tightness 0.075MPa obtains electronic-grade PMDA product, wherein: the crystalline mother solution recycle again after cooling.
The purity of resulting electronic-grade pyromellitic acid anhydride (PMDA) and related data are by shown in the table 1 in the present embodiment.
Embodiment 2:
A) thick acid anhydride is caught in washing two, with the content of PMDA be 75.6% two catch thick acid anhydride 120Kg, and be that 70.8% acetic anhydride 360Kg all joins (two weight ratios of catching thick acid anhydride and solvent are 1: 3) in the enamel reaction still with mass percent concentration, be heated to 101 ℃ then, then be cooled to 29 ℃, carry out suction strainer again, promptly carry out solid-liquid separation, obtain solid materials, the filtrate of solid-liquid separation gained is utilized (reuse) again after distillation;
B) dehydration and decolorization, remove mechanical impurity and ultra-fine foreign material by dehydration and decolorization, the solid materials 100Kg that obtains through solid-liquid separation specifically: will be) by steps A, as dewatering agent and mass percent concentration be 86.8% acetic anhydride 900Kg and put into reacting by heating in the reactor as the gac 1Kg (three's weight part proportioning is 1: 9: 0.01) of discoloring agent, the temperature of reacting by heating is 118 ℃, reaction times is 40min, reaction finishes the back and uses the foreign body filter filtered while hot, filtrate is at 26 ℃ of following crystallisation by cooling, crystallized stock is filtered, obtain crystalline solid;
C) recrystallization, will be by step B) resulting crystalline solid crystallisation by cooling once more in the recrystallization still, specifically: crystalline solid is inserted in the recrystallization still, and add PMDA crystal seed and solvent and carry out crystallisation by cooling once more, crystalline solid, PMDA crystal seed and solvent add in the recrystallization still by 1: 0.1: 2.3 weight ratio, promptly add crystalline solid 80Kg, PMDA crystal seed 8Kg and as solvent and mass percent concentration be 70% acetic anhydride 184Kg, treat aforesaid crystalline solid, after PMDA crystal seed and solvent add in the recrystallization still, then be heated to 120 ℃, then progressively cool off and promptly slowly be cooled to 30 ℃ with 200min, obtain once more the crystallized stock behind the crystallisation by cooling, to the crystallized stock suction filtration, obtain containing the PMDA xln of mother liquor;
D) drying, the PMDA xln that will contain mother liquor places drying machine, and dry 180min under the condition of 163 ℃ and vacuum tightness 0.06MPa obtains electronic-grade PMDA product, wherein: the crystalline mother solution recycle again after cooling.
The purity of resulting electronic-grade pyromellitic acid anhydride (PMDA) and related data are by shown in the table 1 in the present embodiment.
Embodiment 3:
A) thick acid anhydride is caught in washing two, with the content of PMDA be 78.0% two catch thick acid anhydride 120Kg, and be that 40.1% acetic anhydride 480Kg all joins (two weight ratios of catching thick acid anhydride and solvent are 1: 4) in the enamel reaction still with mass percent concentration, be heated to 80 ℃ then, then be cooled to 30 ℃, carry out suction strainer again, promptly carry out solid-liquid separation, obtain solid materials, the filtrate of solid-liquid separation gained is utilized (reuse) again after distillation;
B) dehydration and decolorization, remove mechanical impurity and ultra-fine foreign material by dehydration and decolorization, the solid materials 100Kg that obtains through solid-liquid separation specifically: will be) by steps A, as dewatering agent and mass percent concentration be 99% acetic anhydride 700Kg and put into reacting by heating in the reactor as the gac 1.5Kg (three's weight part proportioning is 1: 7: 0.015) of discoloring agent, the temperature of reacting by heating is 121 ℃, reaction times is 55min, reaction utilizes the foreign body filter filtered while hot after finishing, filtrate is at 27 ℃ of following crystallisation by cooling, crystallized stock is filtered, obtain crystalline solid;
C) recrystallization, will be by step B) resulting crystalline solid crystallisation by cooling once more in the recrystallization still, specifically: crystalline solid is inserted in the recrystallization still, and add PMDA crystal seed and solvent and carry out crystallisation by cooling once more, crystalline solid, PMDA crystal seed and solvent add in the recrystallization still by 1: 0.125: 2.7 weight ratio, promptly add crystalline solid 80Kg, PMDA crystal seed 10Kg and as solvent and mass percent concentration be 55% acetic anhydride 216Kg, treat aforesaid crystalline solid, after PMDA crystal seed and solvent add in the recrystallization still, then be heated to 110 ℃, then progressively cool off and promptly slowly be cooled to 28 ℃ with 240min, obtain once more the crystallized stock behind the crystallisation by cooling, to the crystallized stock suction filtration, obtain containing the PMDA xln of mother liquor;
D) drying, the PMDA xln that will contain mother liquor places drying machine, and dry 150min under the condition of 160 ℃ and vacuum tightness 0.08MPa obtains electronic-grade PMDA product, wherein: the crystalline mother solution recycle again after cooling.
The purity of resulting electronic-grade pyromellitic acid anhydride (PMDA) and related data are by shown in the table 1 in the present embodiment.
Embodiment 4:
A) thick acid anhydride is caught in washing two, with the content of PMDA be 77.5% two catch thick acid anhydride 120Kg, and be that 56.3% acetic anhydride 420Kg all joins (two weight ratios of catching thick acid anhydride and solvent are 1: 3.5) in the enamel reaction still with mass percent concentration, be heated to 90 ℃ then, then be cooled to 32 ℃, carry out suction strainer again, promptly carry out solid-liquid separation, obtain solid materials, the filtrate of solid-liquid separation gained is utilized (reuse) again after distillation;
B) dehydration and decolorization, remove mechanical impurity and ultra-fine foreign material by dehydration and decolorization, the solid materials 100Kg that obtains through solid-liquid separation specifically: will be) by steps A, as dewatering agent and mass percent concentration be 92.6% acetic anhydride 800Kg and put into reacting by heating in the reactor as the gac 3Kg (three's weight part proportioning is 1: 8: 0.03) of discoloring agent, the temperature of reacting by heating is 125 ℃, reaction times is 75min, reaction utilizes the foreign body filter filtered while hot after finishing, filtrate is at 28 ℃ of following crystallisation by cooling, crystallized stock is filtered, obtain crystalline solid;
C) recrystallization, will be by step B) resulting crystalline solid crystallisation by cooling once more in the recrystallization still, specifically: crystalline solid is inserted in the recrystallization still, and add PMDA crystal seed and solvent and carry out crystallisation by cooling once more, crystalline solid, PMDA crystal seed and solvent add in the recrystallization still by 1: 0.15: 3 weight ratio, promptly add crystalline solid 80Kg, PMDA crystal seed 12Kg and as solvent and mass percent concentration be 40% acetic anhydride 240Kg, treat aforesaid crystalline solid, after PMDA crystal seed and solvent add in the recrystallization still, then be heated to 117 ℃, then progressively cool off and promptly slowly be cooled to 29 ℃ with 220min, obtain once more the crystallized stock behind the crystallisation by cooling, to the crystallized stock suction filtration, obtain containing the PMDA xln of mother liquor;
D) drying, the PMDA xln that will contain mother liquor places drying machine, and dry 210min under the condition of 167 ℃ and vacuum tightness 0.07MPa obtains electronic-grade PMDA product, wherein: the crystalline mother solution recycle again after cooling.
The purity of resulting electronic-grade pyromellitic acid anhydride (PMDA) and related data are by shown in the table 1 in the present embodiment.
The step B of the foregoing description 1 to 4) described reaction finish the back with the employed foreign body filter of foreign body filter filtered while hot all for by the disclosed foreign body filter of Chinese invention patent application publication number CN101269280A.Because of very at length having put down in writing the concrete structure and the application of foreign body filter in the specification sheets of this patent application, therefore, the applicant does not give unnecessary details in each embodiment of present patent application once more.
Table 1 is two to catch thick acid anhydride purification step and corresponding product analytical data
Annotate: yield is the yield that the gained solid materials is caught thick acid anhydride after each step operation with respect to raw material two.
Claims (10)
1. catch the method that thick acid anhydride is produced the electronic-grade pyromellitic acid anhydride by two for one kind, it is characterized in that it may further comprise the steps:
A) thick acid anhydride is caught in washing two, two solvents of catching thick acid anhydride and washing usefulness are joined vessel in heating in proportion, and postcooling carries out suction strainer after the cooling; Obtain solid materials, and filtrate is utilized after distillation again;
B) dehydration and decolorization drops into solid materials, dewatering agent and discoloring agent in the reactor in proportion, and reacting by heating adopts the foreign body filter filtered while hot after the reacting by heating, and filtrate is filtered once more behind crystallisation by cooling and obtained crystalline solid;
C) recrystallization with crystalline solid crystallisation by cooling once more in the recrystallization still, to the crystallized stock suction filtration behind the crystallisation by cooling once more, obtains containing the pyromellitic acid anhydride xln of mother liquor;
D) drying, the pyromellitic acid anhydride xln that will contain mother liquor places drying machine to carry out drying, after cooling, obtain the electronic-grade pyromellitic acid anhydride again, the crystalline mother solution cyclically utilizing, wherein: the solvent steps A) is that mass percent concentration is the acetic anhydride of 40-85%; Step B) dewatering agent described in is that mass percent concentration is the acetic anhydride of 80-99%; Step C) solvent that recrystallization is used described in is an acetic anhydride.
2. according to claim 1ly catch the method that thick acid anhydride is produced the electronic-grade pyromellitic acid anhydride by two, it is characterized in that steps A) described in the two weight part proportionings of catching thick acid anhydride and solvent be 1: 2.5-4, described container are enamel reaction still.
3. according to claim 1ly catch the method that thick acid anhydride is produced the electronic-grade pyromellitic acid anhydride by two, it is characterized in that steps A) described in the Heating temperature of heating be 80-110 ℃; Described being cooled to is cooled to 28-32 ℃.
4. according to claim 1 and 2ly catch the method that thick acid anhydride is produced the electronic-grade pyromellitic acid anhydride by two, it is characterized in that described two catch thick acid anhydride and are meant that the quality percentage composition of pyromellitic acid anhydride is that two of 74-78% catches thick acid anhydride.
5. according to claim 1ly catch the method that thick acid anhydride is produced the electronic-grade pyromellitic acid anhydride by two, it is characterized in that step B) described in the weight part proportioning of solid materials, dewatering agent and discoloring agent be 1: 7-10: 0.01-0.03.
6. catch the method that thick acid anhydride is produced the electronic-grade pyromellitic acid anhydride by two according to claim 1 or 5, it is characterized in that described discoloring agent is a gac.
7. according to claim 1ly catch the method that thick acid anhydride is produced the electronic-grade pyromellitic acid anhydride by two, it is characterized in that step B) described in the temperature of reaction of reacting by heating be 115-125 ℃, reaction times is 40-90min, and described crystallisation by cooling is that filtrate with the filtered while hot gained is at 24-28 ℃ of following crystallisation by cooling.
8. according to claim 1ly catch the method that thick acid anhydride is produced the electronic-grade pyromellitic acid anhydride by two, it is characterized in that step C) described in crystallisation by cooling once more be earlier with step B) resulting crystalline solid inserts in the recrystallization still, add PMDA crystal seed and solvent and carry out crystallisation by cooling once more, temperature is risen to 110-120 ℃ again, slow cooling then is to 28-32 ℃, wherein: the weight part proportioning between crystalline solid, PMDA crystal seed and the solvent three is 1: 0.05-0.15: 2-3.
9. according to claim 8ly catch the method that thick acid anhydride is produced the electronic-grade pyromellitic acid anhydride by two, the time that it is characterized in that described slow cooling is 180-240min.
10. according to claim 1ly catch the method that thick acid anhydride is produced the electronic-grade pyromellitic acid anhydride by two, it is characterized in that step D) described in drying be vacuum-drying, vacuum drying vacuum tightness is 0.06-0.08MPa, and drying temperature is 160-170 ℃, and be 150-240min time of drying.
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| CN101250190A (en) * | 2008-04-10 | 2008-08-27 | 常熟市联邦化工有限公司 | Method for refining pyromellitic anhydride by solvent |
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| 丁志平等.精均苯四甲酸二酐的研制.《涂料工业》.2006,第36卷(第11期),38-41. * |
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