CN101244997A - Process for producing 2,6-naphthalenedicarboxylic acid - Google Patents
Process for producing 2,6-naphthalenedicarboxylic acid Download PDFInfo
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- CN101244997A CN101244997A CNA2007100793234A CN200710079323A CN101244997A CN 101244997 A CN101244997 A CN 101244997A CN A2007100793234 A CNA2007100793234 A CN A2007100793234A CN 200710079323 A CN200710079323 A CN 200710079323A CN 101244997 A CN101244997 A CN 101244997A
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Abstract
The invention discloses a method for preparing 2, 6-naphthalene formic acid, which comprises a method for oxidizing 2, 6-diisopropyl naphthalene in liquid phase by using gas with oxygen in stirring and bubbling reactor, and using alkali metal compound or nickel compound as cocatalyst and using lower category aliphatic carboxyl acid under the condition with the existence of catalyst with cobalt compound, manganese compound and bromine compound. The method for preparing the 2, 6-naphthalene formic acid has the advantages of reducing the consumption of lower category aliphatic carboxyl acid, preparing the 2, 6-naphthalene formic acid product with high quality, and satisfying the need for producing naphthalene formic acid glycol ester with high quality.
Description
Technical field
The present invention relates to a kind of preparation technology of compound, specifically, relate to oxygen-containing gas, by the oxidation of Co-Mn-Br series catalysts, preparation target product 2, the 6-naphthalic acid adopts the stirring bubbling reactor to realize this oxidizing reaction.
Background technology
2, the 6-naphthalic acid is the important monomer of preparation various polyester, polyurethane material and liquid crystalline polymers etc., and also is widely used in the dye well field of medicaments.Because 2, the structural high symmetry of 6-naphthalic acid, with glycol reaction obtain poly-2,6-naphthalic acid diethyl ester (PEN) has the characteristic of straight-chain polymer, is a kind of good rigidly, intensity is big, hot workability is excellent high performance material.PEN compares with polyethylene terephthalate (PET), and performances such as PEN thermotolerance, barrier, mechanical property, chemical proofing, uviolresistance are more superior.Because the PEN excellent combination property, development is very fast, and to 2, the demand growth of 6-NDCA and derivative thereof is also very fast.2, the commercial value of 6-NDCA is more and more obvious after nineteen fifty, each company all is being devoted to research and develop 2, the suitability for industrialized production route of 6-NDCA, but because economy and technology fail to realize 2, the scale operation of 6-NDCA so far, therefore research and develop industrial more economically viablely 2, the 6-NDCA synthetic technology has crucial meaning.
At present, domestic the development of 6-naphthalic acid is in space state substantially to alkylnaphthalene liquid-phase oxidation Synthetic 2, has only some summary property reports.Because the alkylnaphthalene oxidation is higher to equipment requirements, the reaction mechanism complexity, by product is many, so difficulty is also bigger, is mainly made by dialkyl group naphthalene (2,6-dimethylnaphthalene, 2,6-diethyl naphthalene and 2,6-diisopropylnaphthalene) liquid-phase oxidation.The external patent report of this having been delivered many different catalytic conditions and oxidizing process process.
Summary of the invention
The objective of the invention is to overcome the deficiencies in the prior art part, and provide a kind of prepare easy, byproduct is less 2, the preparation method of 6-naphthalic acid.
The object of the invention can realize by following measure: the present invention adopts the Co-Mn-Br series catalysts, monocarboxylic one or more mixtures with the 1-6 carbon atom are solvent, oxygen-containing gas oxidation 2,6-diisopropylnaphthalene liquid phase Synthetic 2, the 6-naphthalic acid, reactor is a titanium material autoclave, is furnished with equipment and pressurized gas plenum systems such as condenser, vapour-liquid separator, liquid reflux device and product separation, drying.
Oxidation is that the oxygen-containing gas that contains molecular oxygen is implemented, and reacts in the molar weight of used oxygen-containing gas and the charging 2, and the ratio of 6-diisopropylnaphthalene molar weight is at 20-60, preferred 40-50.The volumetric concentration of oxygen can be 5～100%, is preferably 15～50%.Oxygen-containing gas feeds reactor bottom by inlet pipe and joins in the catalyst system, and even bubbling under the condition of high-speed stirring is beneficial to oxygen and fully contacts with reactant.Add a certain amount of carbonic acid gas in oxygen-containing gas, its add-on is 5%～50%, is preferably 10～30%.Can promote the dissolving of heavy metal manganese salt particulate in the catalyzer, increase the concerted reaction activity of Co-Mn-Br catalyzer, improve 2, the yield of 6-naphthalic acid.
Oxidizing reaction can be carried out under the catalytic condition that one or more heavy metal catalysts are formed, be preferably the oxidation of Co-Mn-Br homogeneous catalysis, the Co/Mn mol ratio is 0.1-4.0, be preferably 0.5-2.0, the Br/Co mol ratio is at 0.2-5, be preferably 0.5-4.0, in catalyst system, add appropriate bases metal (as metal sylvite or sodium salt) and can improve 2, the yield of 6-naphthalic acid, add-on attach most importance to the metal molar number 0.2-4 doubly, preferred 0.3-3.0, wherein basic metal is potassium or sodium compound, or the nickel metallic compound.Catalyzer is the CO-Mn-Br series catalysts, and mole (Co+Mn) is in a ratio of 0.12-0.30 with the mole of diisopropylnaphthalene, preferred 0.15-0.25.
Temperature of reaction is preferably 180-210 ℃ at 170-240 ℃, and temperature low reaction speed is little, and easily the formation reaction intermediate is unfavorable for 2, the further polyreaction of 6-naphthalic acid and ethylene glycol, and the high naphthalene nucleus easy fracture of temperature generates trimellitic acid.Reaction pressure is at 0.8-4MPa, and preferred 2-3MPa suitably improves reaction pressure and helps to accelerate mass transfer between the gas-liquid two-phase, can reduce the mole fraction of acetate in the gas phase simultaneously, thereby reduce the backflow of acetate.Temperature and pressure should match each other according to the vapour pressure of acetate, makes to be reflected at each and constantly all to occur in the liquid phase, if liquid phase very little, products obtained therefrom is black, and purity can reduce a lot.
Reactant 2, the residence time of 6-diisopropylnaphthalene was preferably 3-5 hour at 1-7 hour, and charging finished the back preferably peroxidation 0.5-1 hour, can obviously improve oxidation selectivity and yield.The residence time is relevant with the degree of depth of oxidizing reaction, and 2,6-diisopropylnaphthalene deep oxidation, help target product 2, the generation of 6-naphthalic acid, but the overlong time catalyzer is easy and by product generates complex compound and reduces product purity, improved energy consumption simultaneously, production cost strengthens.Time is too short, and oxidation is incomplete, and the intermediate product that is produced is more.
React the monocarboxylic acid that selected solvent is a 1-6 carbon atom, be preferably glacial acetic acid, propionic acid or the mixture of the two.The mol ratio that solvent accounts for whole raw material is 0.65-0.95, preferred 0.75-0.90.
Add an amount of propionic acid and can improve 2, the yield of 6-naphthalic acid, the amount of minimizing by product trimellitic acid.(Co+Mn) mol ratio with solvent is 0.010-0.050, preferred 0.012-0.030.
The present invention relates to reactor and can adopt intermittence, semicontinuous, continuous mode production, but preferably adopt semicontinuous or continuous mode.
The present invention has following advantage compared to existing technology: the present invention is the consumption that can reduce the lower aliphatic carboxylic acid, reduce the growing amount of by product, avoid the transition oxidation, can prepare high product, highly purified 2,6-naphthalic acid product, thus can satisfy the needs of producing the high quality (ethylene naphthalate).
Description of drawings
Fig. 1 is of the present invention 2,6-naphthalic acid oxidizing reaction process flow sheet
Embodiment
Enumerate 3 embodiment below, the present invention is further specified, but the present invention is not only limited to these embodiment.
According to the present invention, by 2,6-diisopropylnaphthalene liquid-phase oxidation Synthetic 2, a specific embodiments of 6-naphthalic acid is to adopt to stir bubbling reactor.A certain proportion of cobaltous acetate, manganous acetate, Potassium Bromide, potassium acetate add in the solvent pours reactor into after the dissolving, and inside reactor is squeezed into continuously by fresh feed pump in solid material dissolving back.Pressurized air is supplied with from the stirring arm bottom continuously by pressure-regulator.Reaction end gas is through condenser, vapour-liquid separator, and phlegma is back in the reactor, and tail gas is emptying after treatment.Reaction solution separates through solid-liquid through the discharging of bottom discharge mouth, and liquid phase can reuse.Solid phase is washed with glacial acetic acid, again with distilled water wash with after removing solvend, solid drying gets 2,6-naphthalic acid pressed powder.
Embodiment 1:
With 150g glacial acetic acid ((Co+Mn)/solvent is 0.016), 4.98g four water cobaltous acetates, 4.91g four water manganous acetates (the Co/Mn mol ratio is 1), 7.14g Potassium Bromide (the Br/Co mol ratio is 3), 5.90g potassium acetate (promotor/(Co+Mn) mol ratio is 3) adds in the titanium material reactor (mol ratio that solvent accounts for whole system material is 0.85), uses N earlier
2Discharge in the still and be pressurized to 2.4MPa behind the air, stirring heating is warming up to 200 ℃ simultaneously, and pressure is 3.0MPa.Improve stirring velocity to 800r/min, supply with pressurized air with 3.0Nl/min continuously, with 2,6-diisopropylnaphthalene 44.67g ((Co+Mn)/2, the 6-DIPN mol ratio is 0.19) in 4 hours, supply with continuously, supply with and finish 1 hour stopped reaction (always feed the molar weight and 2 of oxygen, the mol ratio of 6-diisopropylnaphthalene is 40) of back continuation oxidation.Emit reaction solution after the cooling release and separate,, get 34.12g khaki color pressed powder with glacial acetic acid and hot distilled water washing after drying through solid-liquid.Behind the liquid phase analysis 2, the purity and the yield of 6-naphthalic acid are respectively 93.2%, 70.7%.
The comparative example 2: the total amount that changes heavy metal catalyst
With 150g glacial acetic acid ((Co+Mn)/solvent mol ratio is 0.024), 7.46g four water cobaltous acetates, 7.34g four water manganous acetates (the Co/Mn mol ratio is 1), 11.96g Potassium Bromide (the Br/Co mol ratio is 3.3), 5.90g potassium acetate (promotor/(Co+Mn) mol ratio is 2.6) adds in the system titanium material reactor (mol ratio that solvent accounts for whole system material is 0.81), 2,6-diisopropylnaphthalene add-on is 44.08g, and other is with embodiment 1.After the drying 36.77g soil white solid powder, by analysis 2, the purity and the yield of 6-naphthalic acid are respectively 94.0%, 77.0%.
The comparative example 3: the mol ratio that changes heavy metal Co and Mn catalyzer
With 150g glacial acetic acid ((Co+Mn)/solvent mol ratio is 0.016), 20.18g four water cobaltous acetates, 9.57g four water manganous acetates (the Co/Mn mol ratio is 2), 7.14g Potassium Bromide, 5.90g potassium acetate add in the titanium material reactor, and 2,6-diisopropylnaphthalene add-on is 43.70g, and other is with embodiment 1.After the drying 36.84g soil white solid powder, by analysis 2, the purity and the yield of 6-naphthalic acid are respectively 95.6%, 65.9%.
The comparative example 4: change promotor
With 150g glacial acetic acid ((Co+Mn)/solvent mol ratio is 0.048), 14.95g four water cobaltous acetates, 14.73g four water manganous acetates (the Co/Mn mol ratio is 1), 11.96g Potassium Bromide (the Br/Co mol ratio is 1.7), 5.90g nickelous acetate (promotor/(Co+Mn) mol ratio is 1.3) adds in the titanium material reactor, 2,6-diisopropylnaphthalene add-on is 43.70g, and other is with embodiment 1.After the drying 36.84g soil white solid powder, by analysis 2, the purity and the yield of 6-naphthalic acid are respectively 94.8%, 79.3%.
Embodiment 2:
With 112.5g glacial acetic acid ((Co+Mn)/solvent mol ratio is 0.022), 37.5g propionic acid (glacial acetic acid: the propionic acid weight ratio is 3), 6.73g four water cobaltous acetates, 6.62g four water manganous acetates, 6.43g Potassium Bromide (the Br/Co mol ratio is 2), 5.30g potassium acetate (promotor/(Co+Mn) mol ratio is 2) adds in the titanium material reactor (mol ratio that solvent accounts for whole system material is 0.86), uses N earlier
2Discharge in the still and be pressurized to 2.4MPa behind the air, stirring heating is warming up to 200 ℃ simultaneously, and pressure is 3.0MPa.Improve stirring velocity to 900r/min, supply with pressurized air with 4.0Nl/min continuously, with chlorobenzene lysed 2,6-diisopropylnaphthalene 40.17g supplied with in four hours continuously, supply with and finish one hour stopped reaction (always feed the molar weight and 2 of oxygen, the mol ratio of 6-diisopropylnaphthalene is 53.3) of back continuation oxidation.Cooling is emitted reaction solution after the release and is separated through solid-liquid, with glacial acetic acid and hot distilled water washing after drying, 33.23g soil white solid powder, by analysis 2, the purity and the yield of 6-naphthalic acid are respectively 95.3%, 77.5%.
The comparative example 2: the amount that changes the solvent propionic acid
With the 75.0g glacial acetic acid, 75.0g propionic acid (glacial acetic acid/propionic acid weight ratio is 1), 6.73g four water cobaltous acetates, 6.62g four water manganous acetates, 6.43g Potassium Bromide, 5.30g potassium acetate add in the titanium material reactor, 2,6-diisopropylnaphthalene add-on is 39.47g, and other is with embodiment 2.After the drying 33.74g soil white solid powder, by analysis 2, the purity and the yield of 6-naphthalic acid are respectively 98.7%, 82.8%.
Embodiment 3:
With 150g glacial acetic acid ((Co+Mn)/solvent mol ratio is 0.022), 6.73g four water cobaltous acetates, 6.62g four water manganous acetates, 6.43g Potassium Bromide, 5.30g potassium acetate add in the titanium material reactor, use N earlier
2Discharge in the still and be pressurized to 2.4MPa behind the air, stirring heating is warming up to 200 ℃ simultaneously, and pressure is 3.0MPa.Improve stirring velocity to 900r/min, supply with the pressurized air that is mixed with 20% (volume) carbonic acid gas with 3.0Nl/min continuously, with 2,6-diisopropylnaphthalene 40.34g supplied with in four hours continuously, and supply finishes the back and continues one hour stopped reaction of oxidation.Cooling is emitted reaction solution after the release and is separated through solid-liquid, with glacial acetic acid and hot distilled water washing after drying, 35.07g soil white solid powder, by analysis 2, the purity and the yield of 6-naphthalic acid are respectively 96.9%, 82.7%.
The comparative example 3: the content that changes carbonic acid gas in the oxygen-containing gas
With the 150g glacial acetic acid, 6.73g four water cobaltous acetates, 6.62g four water manganous acetates, 6.43g Potassium Bromide, 5.30g potassium acetate, 14.0g water add in the self-control titanium material reactor, supply with the pressurized air that is mixed with 30% (volume) carbonic acid gas with 3.0Nl/min continuously, add 2,6-diisopropylnaphthalene 4 0.05g, other is with embodiment 3.After the drying 34.12g soil white solid powder, by analysis 2, the purity and the yield of 6-naphthalic acid are respectively 98.0%, 82.0%.
Claims (9)
1. one kind 2, the preparation method of 6-naphthalic acid is characterized in that: this method uses the lower aliphatic carboxylic acid to be solvent in stirring bubbling reactor, with cobalt compound, manganic compound and bromine compounds is catalyzer, basic metal is promotor, and temperature of reaction is 170-240 ℃, and reaction pressure is at 0.8-4MPa, reaction times is under 1-7 hour condition, with oxygen containing gas liquid-phase oxidation 2,6-diisopropylnaphthalene preparation 2,6-naphthalic acid product.
2. according to claim 12, the preparation method of 6-naphthalic acid, it is characterized in that: the solvent that uses is monocarboxylic one or more mixtures of 1-6 carbon atom, preferred glacial acetic acid or propionic acid, or both mixtures, the mol ratio that solvent accounts for whole raw material is 0.65-0.95, preferred 0.75-0.90.
3. according to claim 12, the preparation method of 6-naphthalic acid is characterized in that: temperature of reaction is preferably 180-210 ℃ at 170-240 ℃; Reaction pressure is at 0.8-4MPa, preferred 2-3MPa; Reaction times was preferably 3-5 hour at 1-7 hour.
4. according to claim 12, the preparation method of 6-naphthalic acid is characterized in that: catalyzer is the Co-Mn-Br series catalysts, and (Co+Mn) mol ratio with diisopropylnaphthalene is 0.12-0.30, preferred 0.15-0.25.
5. according to claim 12, the preparation method of 6-naphthalic acid is characterized in that: the ratio of catalyzer, and (Co+Mn) mol ratio with solvent is 0.010-0.050, preferred 0.012-0.030; The Co/Mn mol ratio is preferably 0.5-2.0 at 0.1-4.0; The Br/Co mol ratio is preferably 0.5-4.0 at 0.2-5.
6. according to claim 12, the preparation method of 6-naphthalic acid is characterized in that: the add-on of promotor attach most importance to the metal molar number 0.2-4 doubly, preferred 0.3-3.0, wherein basic metal is potassium or sodium compound, or the nickel metallic compound.
7. according to claim 12, the preparation method of 6-naphthalic acid is characterized in that: in the molar weight of oxygen-containing gas and the charging 2, the ratio of 6-diisopropylnaphthalene molar weight is at 20-60, preferred 40-50.
8. according to claim 12, the preparation method of 6-naphthalic acid is characterized in that: the volumetric concentration that feeds oxygen in the oxygen-containing gas is 5～100%, is preferably 15～50%.
9. according to claim 12, the preparation method of 6-naphthalic acid is characterized in that: add a certain amount of carbonic acid gas in the oxygen-containing gas, its add-on is 5%～50% of a gas volume amount, preferred 10-30%.
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| CNA2007100793234A CN101244997A (en) | 2007-02-16 | 2007-02-16 | Process for producing 2,6-naphthalenedicarboxylic acid |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101524649B (en) * | 2009-04-28 | 2010-09-22 | 岳阳蓬诚科技发展有限公司 | Preparation method of alkyl naphthalene oxidation catalyst |
| CN103664582A (en) * | 2012-09-05 | 2014-03-26 | 中国石油化工股份有限公司 | Solvent replacement method of coarse 2,6-naphthalic acid oxidation slurry |
| CN103880654A (en) * | 2012-12-19 | 2014-06-25 | 中国石油化工股份有限公司 | Preparation method for 2,6-naphthalenedicarboxylic acid |
| CN103965039A (en) * | 2013-02-05 | 2014-08-06 | 中国石油化工股份有限公司 | Method for synthesizing 2,6-naphthalenedicarboxylic acid |
| CN107641078A (en) * | 2017-10-30 | 2018-01-30 | 北京石油化工学院 | A kind of method that propiono Fluidized bed of 2 methyl 6 prepares 2,6 naphthalenedicarboxylic acids |
| CN110172017A (en) * | 2019-05-28 | 2019-08-27 | 北京石油化工学院 | A method of high-purity naphthalic acid is prepared by raw material of naphthalene |
| CN112645811A (en) * | 2019-10-10 | 2021-04-13 | 中国石油化工股份有限公司 | Method for preparing 2,6-naphthalene dicarboxylic acid by oxidizing 2, 6-diisopropyl naphthalene |
| CN114050245A (en) * | 2021-11-16 | 2022-02-15 | 中科南京绿色制造产业创新研究院 | Composite cathode material with spring-shaped lamellar structure and preparation method and application thereof |
| CN115925531A (en) * | 2022-12-15 | 2023-04-07 | 沧州临港丰亚化工有限公司 | Method for preparing 2, 6-naphthalene dicarboxylic acid by using aromatic anhydride as raw material |
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- 2007-02-16 CN CNA2007100793234A patent/CN101244997A/en active Pending
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101524649B (en) * | 2009-04-28 | 2010-09-22 | 岳阳蓬诚科技发展有限公司 | Preparation method of alkyl naphthalene oxidation catalyst |
| CN103664582B (en) * | 2012-09-05 | 2015-11-18 | 中国石油化工股份有限公司 | The method of thick NDA oxidation slurry solvent exchange |
| CN103664582A (en) * | 2012-09-05 | 2014-03-26 | 中国石油化工股份有限公司 | Solvent replacement method of coarse 2,6-naphthalic acid oxidation slurry |
| CN103880654A (en) * | 2012-12-19 | 2014-06-25 | 中国石油化工股份有限公司 | Preparation method for 2,6-naphthalenedicarboxylic acid |
| CN103880654B (en) * | 2012-12-19 | 2015-09-09 | 中国石油化工股份有限公司 | The preparation method of NDA |
| CN103965039A (en) * | 2013-02-05 | 2014-08-06 | 中国石油化工股份有限公司 | Method for synthesizing 2,6-naphthalenedicarboxylic acid |
| CN103965039B (en) * | 2013-02-05 | 2015-10-21 | 中国石油化工股份有限公司 | The method of synthesis NDA |
| CN107641078A (en) * | 2017-10-30 | 2018-01-30 | 北京石油化工学院 | A kind of method that propiono Fluidized bed of 2 methyl 6 prepares 2,6 naphthalenedicarboxylic acids |
| CN110172017A (en) * | 2019-05-28 | 2019-08-27 | 北京石油化工学院 | A method of high-purity naphthalic acid is prepared by raw material of naphthalene |
| CN112645811A (en) * | 2019-10-10 | 2021-04-13 | 中国石油化工股份有限公司 | Method for preparing 2,6-naphthalene dicarboxylic acid by oxidizing 2, 6-diisopropyl naphthalene |
| CN114050245A (en) * | 2021-11-16 | 2022-02-15 | 中科南京绿色制造产业创新研究院 | Composite cathode material with spring-shaped lamellar structure and preparation method and application thereof |
| CN114050245B (en) * | 2021-11-16 | 2023-12-15 | 中科南京绿色制造产业创新研究院 | Composite positive electrode material with spring-like lamellar structure, and preparation method and application thereof |
| CN115925531A (en) * | 2022-12-15 | 2023-04-07 | 沧州临港丰亚化工有限公司 | Method for preparing 2, 6-naphthalene dicarboxylic acid by using aromatic anhydride as raw material |
| CN115925531B (en) * | 2022-12-15 | 2023-07-11 | 信诺立兴(沧州渤海新区)化工有限公司 | Method for preparing 2,6 naphthalene dicarboxylic acid by taking aromatic anhydride as raw material |
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