CN1024660C - Oxidation process for mfg. aromatic acids from alkylaromatic compounds - Google Patents
Oxidation process for mfg. aromatic acids from alkylaromatic compounds Download PDFInfo
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- CN1024660C CN1024660C CN 88107608 CN88107608A CN1024660C CN 1024660 C CN1024660 C CN 1024660C CN 88107608 CN88107608 CN 88107608 CN 88107608 A CN88107608 A CN 88107608A CN 1024660 C CN1024660 C CN 1024660C
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Abstract
The present invention relates to a new method for oxidizing dimethylbenzene and trimethyl benzene into the corresponding phthalic acid or benzenetricarboxylic acid by molecular oxygen under the condition of a liquid phase. The method is carried out at the temperature of about 100 to 260 DEG C. The method comprises the step that the oxidizing reaction is carried out in the existence of a bromine containing source and a catalyst system of nickel, manganese and zirconium. The phthalic acid and the benzenetricarboxylic acid have wide industrial application comprising the manufacture of polyester, polyamide, fibers and thin films.
Description
The combination (wherein containing mn ion at least) of heavy transition metal-bromide anion has the oxidation catalysis effect, and adding nickel and zirconium can greatly improve aforesaid combination the methyl on the phenyl ring is changed into carboxylic acid group's catalytic activity, and can save the expensive catalysts cobalt.The quick oxygen consumption that this advantages of high catalytic activity shows as the initial stage continues to grow, the solvent degree of combustion is lower and productive rate improves.
United States Patent (USP) 2,245 points out to prepare with liquid phase rather than vapor phase oxidation the possibility of benzene carboxylic acid No. 528 the earliest.In the liquid phase of saturated lower fatty acid, in about 100 ℃ to about 320 ℃ temperature with keep under the pressure that lipid acid is liquid phase, utilize the transformation of variable valency metal, especially cobalt that katalysis is provided.According to this patent, use ketone (for example methylethylketone) or aldehyde (for example acetaldehyde) can promote this katalysis easily.It's a pity that this class is by the promoted variable valency metal katalysis of aldehydes or ketones, just for one, two and Three methyl Benzene change into its corresponding phenylformic acid: phenylformic acid, toluic acid and mesitylenic acid are just effectively.For the katalysis of the promoted cobalt of aldehydes or ketones in liquid phase acetate, after a while with what be walk abreast two independently low temperature modification method (80 ℃-100 ℃) conversion of dimethylbenzene to phthalic acid, especially p-Xylol to terephthalic acid of viable commercial is provided really, but to use the cobalt of suitable high density.It is commercial more desirable that the combination of cobalt and manganese and brominated thing becomes, and United States Patent (USP) 2,833 has disclosed this point No. 816.But cobalt is very expensive, and only can be obtained by the source outside the U.S. and those countries that may cut off this valuable metal supply.
Have been found that for the liquid-phase oxidation of dimethylbenzene or 1 nickel and zirconium are uniquely in the metal can improve bromo-manganese system catalytic activity greatly with molecular oxygen.
Be that nickel and zirconium combine effectively with manganese unexpectedly.The existence of bromine is conclusive in our method.If there is not bromine, then can not get high productive rate.Day disclosure special permission 7710,229, Deutsches Reichs-Patent prospectus 2,804,156, United States Patent (USP) 2,833, No. 816 and european patent application have been mentioned nickel catalyzator 0,041, No. 784, but do not combine with manganese or zirconium.
The world production ability of terephthalic acid is above 10,000,000,000 pounds.At present, pure terephthalic acid is made in two steps: (1) uses molecular oxygen, with p xylene oxidation, (2) are with terephthalic acid crude product recrystallization and hydrogenation in water, with its purification in acetic acid solvent for cobalt/manganese/bromine catalyst.Cobalt is a component the most expensive in the catalyst system.Therefore, replace cobalt that very big economic benefit is arranged with certain other metal.Our novel method is succeedd in this point just.
Nickel among the present invention: zirconium: the grammeatom ratio of manganese is in about 33: 1: 12 to 80: 1: 43 scope.Better by 40: 1: 20 to about 70: 1: 40 scope.The ratio of total metal content (the nickel manganese addition adds zirconium) and bromine is by milligram-atom, in about scope of 0.5 to 1.5.So, want p-Xylol, m-xylene or the 1 of oxidation for every mol, use about 4 to 20 milligram-atom nickel, 0.1 to 0.30 milligram-atom zirconium, the total manganese amount of 2 to 10 milligram-atoms and the bromine of about 8 to 24 milligram-atoms.For 1, m-xylene and p-Xylol, the ratio of metal and bromine is comparatively desirable between 0.7 to 1.0.Replacing in the oxidation system of water as reaction medium with the aliphatic acid (for example acetate) that is less than 5 carbon atoms, nickel-zirconium catalyst also is effective.
Nickel and zirconium can be added in the reaction with any form that can be dissolved in two or the Three methyl Benzene oxidized in acetate.For example, the octylate of nickel or zirconium or naphthenate can be used for when reaction solvent does not exist two or the Three methyl Benzene oxidation with manganese octoate or manganese naphthenate, and the acetate that then can use nickel, zirconium and manganese when acetic acid solvent exists easily is with two or the Three methyl Benzene oxidation.Nickel and zirconium are easy to obtain, and very are fit to do with acetate or water the liquid-phase oxidation effect of reaction solvent.
With nickel and zirconium enhanced oxygenizement, the oxygen level of source of molecular oxygen can change from air to oxygen for of the present invention.For the oxygenizement of carrying out under 100 ℃ to 260 ℃ temperature, air is a source of molecular oxygen preferably.With regard to the oxygenizement of carrying out with molecular oxygen, temperature range is about 120 ℃ to 220 ℃ preferably.For this oxygenizement, its minimal pressure should be to keep substantially that the reaction medium of 70-80% is a liquid phase, this medium or pure two or Three methyl Benzene or the acetate of these methylbenzene and 70-80%.If use acetate or water solvent, its amount can be equivalent to every part two or Three methyl Benzene 1-10 part by weight.Evaporate because of reaction heat so the methylbenzene in liquid phase and/or acetate is not easily under the condensation, condensation product is sent back in the oxidizing reaction again, and this also is a kind of heat extraction and the currently known methods of controlling the exothermic oxidation reaction temperature thus.
As the methyl substituted benzene of desiring oxidation, its result has shown nickel used according to the invention and the obtained benefit of zirconium to the oxidizing reaction of following illustrative and contrast with 1, m-xylene or p-Xylol.
With catalyst component, 1,2,4-trimethylbenzene, p-Xylol or m-xylene and acetate or water all are encapsulated in and carry out batch oxidation in the reactor; Pressure controlled valve is placed 150 pounds/square inch (valve is on vent lines) earlier; With nitrogen reactor is forced into 150 pounds/square inch; The reactor content is heated to the temperature of wanting, and is 160 ℃ for 1, feeds pressurized air with the liquid phase of constant flow rate in reactor then.About 20 ℃ water coolant is fed in the chuck of condenser portion.Each oxidation all proceeds in the vent gas oxygen near the 14%(volume as far as possible) till.
Originally oxidations all in following each example are all carried out under 150 pounds/square inch gauge pressure, 1,2, the situation initial oxidation temperature of 4-Three methyl Benzene is 160 ℃, acetate and 1,2, the weight ratio of 4-Three methyl Benzene or dimethylbenzene is about 1.87: 1, uses air as source of molecular oxygen.Used oxidation reactor is 2 liters of titanium matter garden cylindricality autoclaves of band whipping appts.Water cooling formula condenser is housed so that reactor is returned in most of volatile compound condensation and foldback near the top of autoclave.Device and analytical equipment that discharging waste gas mixture (nitrogen, not the steam of oxygen, carbon oxides, water vapor and uncooled acetate and some unreacted dimethylbenzene usefulness or superfluous) is arranged after condenser system are in order to measure in the waste gas content by oxygen, carbonic acid gas and the carbon monoxide of the dry weight basis of no acetate.The waste gas sample is being analyzed O
2, CO
2Flow through before three cold-traps (for example dry ice-propanone cooling) earlier with CO.Reactor pack into the 1 or the dimethylbenzene of 225 grams are so the weight ratio that the acetate of 420 grams are equivalent to solvent and 1 is 1.87: 1.Catalyst component, 1 and acetate all packed into carry out the oxidation of 1 in the reactor in batches.The reactor sealing.Originally pressure controlled valve places 150 pounds/square inch (valve is on delivery pipe).Pressure is increased to 400 pounds/square inch gradually by 150 pounds/square inch within 55 minutes, and correspondingly, temperature is rising to 210 ℃ with following period of time by 160 ℃.Reactor is to be pressurized to 150 pounds/square inch with nitrogen, is heated to starting temperature then.After this, import pressurized air in the liquid phase in reactor.Each oxidation all proceeds in the discharging gas oxygen near the 14%(volume as far as possible) till.
After oxidation finishes, collect the total reactor effluent, deliver and carry out the aromatic acid analysis.
Productive rate (back report) calculates by the product molecular fraction of every mole of 1 of packing into or dimethylbenzene.
The table I and the II of back illustrated other relevant details of the oxidizing reaction that exemplifies and the result who prepares like this.Nickel and zirconium use with the form of nickelous acetate and zirconium acetate, but the compound of other acetate or water miscible nickel and zirconium also is applicable to this novel method.Used manganese is its acetate tetrahydrate.Brominated thing is a Hydrogen bromide, but also can be with other brominated thing, for example HBr, BR
2, KBr, NaBr, NH
4Br, bromotoluene, tetrabromoethane etc.
Example
As show in the I shown in the example 2,4,8, Ni/Br, Mn/Br and Mn/Zr/Br catalyzer have activity in conjunction with the oxidation to alkylaromatic hydrocarbon.The interact summation of the total effect be defined as each reagent effect when independently working of synergy greater than them.For example, if effect is defined as 1,2, the oxidation rate of 4-Three methyl Benzene (for example one in the microreactor of 100 ℃ of operations, measure), so, if the synergy interaction less than Ni/Mn/Zr/Br, has then taken place in the speed sum of Ni/Br and Mn/Zr/Br catalyzer.In homogeneous oxidizing, increase catalyst concn oxidation rate is improved, shown in example 1,2,3,4,6,7 and 8,9 in the table I.Therefore, when determining whether that synergy has taken place to interact, it is important guaranteeing to compare under the catalyst concn that equates.In following each example, noticed this condition.All examples are listed in the table 1 is oxidation rate with milliliter oxygen/minute expression.
In this manual, 15 examples have illustrated the synergism of Ni/Mn/Zr/Br catalytic body system.
The product that all alkylaromatic hydrocarbons are oxidized to aromatic acid is water.The concentration of water in acetate becomes with the alkyl number on the aromatics, the pressure of oxidizing reaction etc.Therefore, the oxidation rate in the table I is measured as the function of the water in the microreactor.Obviously, for water concentrations all in the acetate, all there is synergism.
Example 12 and 13 in the table I is compared with example 14, illustrate that the Ni/Mn/Zr/Br catalyzer has and the desired same activity of Co/Mn/Br catalyzer.
The catalyzer variable that productive rate is had the greatest impact is the concentration of nickel.
The experimental data that table is listed in the I be with 1 as oxide, the table II is an oxide with p-Xylol and m-xylene then.All observed the synergism of zirconium with all these raw materials to the Ni/Mn/Br catalyzer.
The table I
Be oxidized to 1,2 at 1, all kinds of catalyzer in the 4-benzenetricarboxylic acid
(a)Oxidation rate
Example 1234
Catalyst type Ni/Br Ni/Br Mn/Br Mn/Br
Catalyzer (mmole)
Nickel 2.01 4.02 0.0 0.0
Manganese 0.0 0.0 2.01 4.02
Zirconium 0.0 0.0 0.0 0.0
Bromine 2.01 4.02 2.01 4.02
Oxidation rate
Milliliter O
2/ minute
0.3%H
2O 0.0 0.05 1.18 1.26
5.0%H
2O 0.0 - 1.87 .58
13.0%H
2O 0.0 - 0.71 .10
20.0%H
2O 0.0 - 0.05 .05
Table I (continuing)
Example 567
Catalyst type Zr/Br Ni/Zr/Br Ni/Zr/Br
Catalyzer (mmole)
Nickel 0.0 2.02 4.02
Manganese 0.0 0.0 0.0
Zirconium 0.19 0.19 0.38
Bromine 0.19 2.02 4.02
Oxidation rate
Milliliter O
2/ minute
0.3%H
2O 0.0 0.0 0.05
5.0%H
2O 0.0 0.0 -
13.0%H
2O 0.0 0.0 -
20.0%H
2O 0.0 0.0 -
Example 89 10 11
Catalyst type Mn/Zr/Br Mn/Zr/Br Ni/Mn/Br Ni/Mn/Br
Catalyzer (mmole)
Nickel 0.0 0.0 2.01 2.01
Manganese 2.01 4.02 2.01 2.01
Zirconium 0.19 0.38 0.0 0.0
Bromine 2.01 4.02 4.02 4.02
Oxidation rate
Milliliter O
2/ minute
0.3%H
2O 2.21 5.91 6.78 6.53
5.0%H
2O 2.30 4.80 2.46 1.78
13.0%H
2O 1.32 3.71 0.51 0.46
20.0%H
2O 0.46 1.44 0.10 0.15
Example 12 13 14
Catalyst type Ni/Mn/Zr/Br Ni/Mn/Zr/Br Co/Mn/Br
Catalyzer (mmole)
Nickel 2.01 2.01 2.01
Manganese 2.01 2.01 2.01
Zirconium 0.38 0.38 0.0
Bromine 4.02 4.02 4.02
Oxidation rate
Milliliter O
2/ minute
0.3%H
2O 7.01 6.06 5.64
5.0%H
2O 5.60 5.30 4.33
13.0%H
2O 3.00 4.22 1.43
20.0%H
2O 1.16 1.29 0.77
(a). be reflected in the glass reactor that contains 10.0 milliliters of 1 and 100.0 milliliters of acetic acid and carry out.Oxygen source is an air, with the speed of the 52 ml/min vitreous clinker by reactor bottom.Use the Beckman oxygen analyzer constantly to measure the oxygen concn that discharges in the gas.Calculate rate of oxygen absorption by the oxygen concn in the discharging gas and the air velocity of inflow reactor.Temperature keeps 95 ℃, and pressure is normal atmosphere.
The table II
All kinds of catalyzer
aOxidation rate to p-Xylol and m-xylene oxygenizement
Example 15 16 17 18
Catalyst type Ni/Mn/Br Ni/Mn/Zr/Br Ni/Mn/Br Ni/Mn/Zr/Br
Catalyzer (mmole)
Nickel 2.01 2.01 2.01 2.01
Manganese 2.01 2.01 2.01 2.01
Zirconium 0.0 .19 0.0 0.19
Bromine 4.02 4.02 2.01 4.02
Oxidation rate
Milliliter O
2/ minute
0.3%H
2O 2.92 5.70 6.68 6.31
5.0%H
2O 0.49 2.13 .56 1.66
13.0%H
2O 0.35 1.44 .23 0.62
20.0%H
2O 0.20 1.14 .16 .34
(a) be reflected at and contain 2.01 mmole cobaltous acetate (II) tetrahydrates, carry out in the glass reactor of 2.01 mmole manganous acetate (II) tetrahydrates, 4.00 mmole Sodium Bromides and 100.0 milliliters of acetate.Oxygen source is an air, with the speed of the 52 ml/min vitreous clinker by reactor bottom.Use the Beckman oxygen analyzer constantly to measure oxygen concn in the discharging gas.Calculate oxygen absorption speed by oxygen concn and the air velocity by reactor in the discharging gas.Temperature keeps 95 ℃, and pressure is normal atmosphere.Contain 15.0 milliliters of p-Xylol in the example 17 and 18, contain 15.0 milliliters of m-xylenes in the example 19 and 20.
The table III has been listed the data that obtain under temperature of mentioning previously and pressure, these conditions are near the industrial production condition.Table I previously discussed draws in being reacted by cryogenic microreactor with the data in the table II, in order to the effect of isolation and upright each catalyst component of arc.
In the example 19 of table III, the 225 gram 1 of in 2 liters autoclave, packing into, the acetate of 420 grams 95%, 1.89 gram cobaltous acetates, 0.84 gram manganous acetate, the HBr solution of the aqueous solution (17% weight) of the zirconium of 0.053 gram and 0.34 gram 48%.The temperature of autoclave is increased to 160 ℃, in stirring down air is fed reactor.Oxidation this moment begins, and temperature is risen to 210 ℃, pressure in 60 minutes and increases to 400 pounds/square inch by 150 pounds/square inch.Pressure helps controlled temperature, comes controlled temperature but also feed refrigerant by the coil pipe in being immersed in reactor.
Reactor is discharged air cooling but to remove condensable steam, and the gas of gained is delivered to oxygen and capnograph, measures level of response and degree of combustion.In whole batch cycle, constantly add the ending catalyzer.Add 1.05 gram HBr solution in this example in reactor, 0.11 gram manganous acetate and the solution of 0.077 gram zirconium in 38 gram acetate (85% aqueous solution) are as the ending catalyzer.Oxygen level reaches after 14% in discharging gas, stops oxidizing reaction, collects the content of reactor.The washing reaction device, washings and reactor stream fluid lump together drying.To the solid analysis 1,2 of gained, 4-benzenetricarboxylic acid and by product.Calculate the mole yield percentage of each component, the gained result is normalized to 100%(and sees Table III)
In table III example 20, step is identical but catalyst concn is as follows: initial-4.75 gram nickelous acetates, 2.00 gram manganous acetates, 0.16 gram zirconium solution, 0.84 gram HBr solution.Ending-2.60 gram HBr solution, 0.03 gram zirconium solution, 0.55 gram manganous acetate.
The table III
The best Ni-based oxidation of 1 and the comparison of best cobalt-based oxidation
Example 19 examples 20
Best cobalt-based
1Best Ni-based
2
1,2,4-benzenetricarboxylic acid 89.8 89.6
Intermediate 0.8 1.1
Low boilers 2.7 2.7
High boiling product 1.2 1.1
COx 5.5 5.5
Reaction times (branch) 65 63
(1) cobalt=0.199 weight %; Initial Mn=0.084 weight %;
Initial Zr=0.004 weight %; Ending Mn=0.01 weight %;
Ending Zr=0.005 weight %; All by 1.
(2) nickel=0.50 weight %; Initial Mn=0.20 weight %;
Initial Zr=0.012 weight %; Ending Mn=0.05 weight %;
Ending Zr=0.002 weight %; All by 1.
Productive rate is normalized to 100%.The quality accountability of two examples is 90.5-91.0.
Claims (6)
1, a kind of under liquid-phase condition with molecular oxygen with two and Three methyl Benzene be oxidized to the method for phthalic acid and benzene tricarboxylic acid, the lipid acid that is less than five carbon atoms is arranged in the oxidizing reaction system, or water, or the mixture of lipid acid and water exists, about 100 ℃ to 260 ℃ of temperature, the reaction medium that pressure then can be kept 70-80% is a liquid phase, this method is included in brominated source and nickel, the catalyst system of zirconium and manganese carries out above-mentioned oxidizing reaction under existing, for the every mol p-Xylol in the oxidizing reaction, m-xylene or 1,2, the 4-Three methyl Benzene, about 4 to 20 milligram-atom nickel are arranged in the catalyzer, about 0.10 to 0.30 milligram-atom zirconium, the bromine of the manganese of about 2 to 10 milligram-atoms and about 8 to 24 milligram-atoms.
2, the process of claim 1 wherein nickel: zirconium: the grammeatom of manganese is than in about 33: 1: 12 to 80: 1: 43 scope, and solvent is acetate or water.
3, the method for claim 2, wherein p-Xylol is oxidized to terephthalic acid.
4, the method for claim 2, wherein m-xylene is oxidized to m-phthalic acid.
5, the method for claim 2, wherein 1 is oxidized to 1,2, the 4-benzenetricarboxylic acid.
6, claim 1 described under liquid-phase condition with molecular oxygen to 1,2, the 4-Three methyl Benzene carries out the method for liquid-phase oxidation, temperature of reaction is in about 100 ℃ to 260 ℃ scope, the reaction medium that reaction pressure can be kept 70-80% is a liquid phase, under existing, the catalyst system that is reflected at brominated source and nickel, zirconium and manganese carries out, for the every mol 1 in the oxidizing reaction, 2, the 4-Three methyl Benzene, about 4 to 20 milligram-atom nickel are arranged, about 0.10 to 0.30 milligram-atom zirconium, the bromine of the manganese of about 2 to 10 milligram-atoms and about 8 to 24 milligram-atoms in the catalyzer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 88107608 CN1024660C (en) | 1987-05-18 | 1988-11-05 | Oxidation process for mfg. aromatic acids from alkylaromatic compounds |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US07/050,860 US4786753A (en) | 1987-05-18 | 1987-05-18 | Oxidation process for the manufacture of aromatic acids from alkylaromatic compounds |
| CN 88107608 CN1024660C (en) | 1987-05-18 | 1988-11-05 | Oxidation process for mfg. aromatic acids from alkylaromatic compounds |
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| Publication Number | Publication Date |
|---|---|
| CN1042534A CN1042534A (en) | 1990-05-30 |
| CN1024660C true CN1024660C (en) | 1994-05-25 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 88107608 Expired - Fee Related CN1024660C (en) | 1987-05-18 | 1988-11-05 | Oxidation process for mfg. aromatic acids from alkylaromatic compounds |
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| US5693856A (en) * | 1996-01-16 | 1997-12-02 | The Boc Group, Inc. | Production of terephthalic acid |
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