CA2306935A1 - Continuous method for producing aromatic amines - Google Patents
Continuous method for producing aromatic amines Download PDFInfo
- Publication number
- CA2306935A1 CA2306935A1 CA002306935A CA2306935A CA2306935A1 CA 2306935 A1 CA2306935 A1 CA 2306935A1 CA 002306935 A CA002306935 A CA 002306935A CA 2306935 A CA2306935 A CA 2306935A CA 2306935 A1 CA2306935 A1 CA 2306935A1
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- CA
- Canada
- Prior art keywords
- aromatic
- process according
- hydrogen
- reactor
- polynitro
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C209/00—Preparation of compounds containing amino groups bound to a carbon skeleton
- C07C209/30—Preparation of compounds containing amino groups bound to a carbon skeleton by reduction of nitrogen-to-oxygen or nitrogen-to-nitrogen bonds
- C07C209/32—Preparation of compounds containing amino groups bound to a carbon skeleton by reduction of nitrogen-to-oxygen or nitrogen-to-nitrogen bonds by reduction of nitro groups
- C07C209/36—Preparation of compounds containing amino groups bound to a carbon skeleton by reduction of nitrogen-to-oxygen or nitrogen-to-nitrogen bonds by reduction of nitro groups by reduction of nitro groups bound to carbon atoms of six-membered aromatic rings in presence of hydrogen-containing gases and a catalyst
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention relates to a continuous method for producing aromatic diamines and/or polyamines by means of catalytic hydrogenation of corresponding aromatic dinitro and/or polynitro compounds with hydrogen. The invention is characterized in that in a reactor with a catalytic fixed bed or shower bed with a pressure ranging from 5 to 100 bar and at a reaction temperature ranging from 100 to 220 ~C, a) the aromatic dinitro and/or polynitro compounds are optionally introduced in the presence of a solvent in a product stream comprised of an essentially recycled hydrogenated product, water and hydrogen, and b) a part of the product stream is continuously withdrawn from the reactor system.
Description
Le A 32 613 -foreign countries A continuous process for the preparation of aromatic amines The invention relates to a continuous process for the preparation of aromatic di- and polyamines by catalytic hydrogenation of the di- and polynitro compounds corresponding to the amines at high temperatures and optionally with simultaneous removal of heat from the reaction mixture in order to generate steam with a pressure above atmospheric of > 1.5 bar abs. on a fixed bed.
Processes for the preparation of aromatic amines by catalytic hydrogenation of the nitro compounds on which they are based are known in large number (DE-A-2 135 155, DE-A-2 106 644, DE-A-4 435 839, EP-A-0 696 573 and WO 97/20 804).
Generally speaking, the industrial-scale catalytic hydrogenation of aromatic polynitro compounds in suspensions is carried out at low temperatures because there is a risk of uncontrolled secondary reactions during the hydrogenation of aromatic polynitro compounds at high temperatures. These secondary reactions may lead to the formation of unwanted by-products and hence to reductions in yield. Reactions involving hydrogenation of the nucleus, hydrogenolytic cleavage or the formation of high molecular weight, tar-like products may be mentioned by way of example in this connection. Explosive secondary reactions may also take place which are due to the highly exothermic course of the nitro group reaction and its high rate of reaction at relatively high temperatures.
When aromatic polynitro compounds are reacted with hydrogen, a considerable amount of heat is released. Advantageous hydrogenation processes are those in which the increased reaction energy does not have to be destroyed with an expenditure of energy but in which the reaction energy can be utilised economically in the form of steam production.
p0 Fouling and deposits of catalysts are observed time and again in the catalytic suspension processes. Product impurities, relatively poor hydrogenation yields and LeA32613 , _2_ high catalyst consumptions are often associated with this. The expenditure on cleaning and maintenance is considerable.
Thelen et al. (DE-A-2 135 154 and DE-A-2 135 155) have circumvented these disadvantages by the description of catalytic hydrogenation on a fixed bed. In spite of the advantageous arrangement of the catalyst in a fixed bed, the disadvantages are that the quantity of heat is removed in the reactor, the dimensions and structure of the reactor and the deposition of the catalyst in spinel form onto the cooling tubes are very expensive. The throughput of aromatic polynitro compounds is small. The removal of heat is problematic and the reaction must be carried out only at low temperatures.
The catalytic hydrogenation of aromatic vitro compounds on a fixed bed in a combination of two fixed bed reactors is described in WO 97/20 804 (Chambost et al.).
The division of the product quantities after the first reactor with simultaneous gas separation is problematic and expensive. Disadvantages of the process described here are the use of two reactors and the low reaction temperatures of up to 120°C.
Moreover, large quantities of solvents such as alcohols or ethers are used in some cases, the solvent having to be separated from the aromatic diamine after the reaction and optionally worked up.
The object was, therefore, to provide an improved process for the preparation of amines by hydrogenation of aromatic vitro compounds which makes it possible to operate without solvents or only with little solvent even at high temperatures without secondary reactions or fouling occurring.
The invention relates to a continuous process for the preparation of aromatic di- and/or polyamines by catalytic hydrogenation of the corresponding aromatic di- and/or polynitro compounds with hydrogen, in which, in a reactor with a catalytic fixed bed or trickle bed at a pressure between 5 and 100 bar and a reaction temperature from 100 to 220°C, rPe~~~~z a) the aromatic di- and/or polynitro compounds, optionally in the presence of a solvent, are introduced into a product stream comprising essentially recycled hydrogenated product, water and hydrogen, and b) a part of the product stream is removed continuously from the reactor system.
A pressure of 10 to 80 bar and an operating temperature of 150 to 200°C
are preferably maintained in the reactor.
The reactor used preferably has an external heat exchanger so that the heat of reaction produced can be used for steam generation.
The product discharge may take place at any place in the reactor system. The discharge takes place preferably after the external heat exchanger before pumping. The product stream removed from the reaction system is advantageously cooled to about 150 to 160°C.
Examples of aromatic nitro compounds used in preference are:
1,3-dinitrobenzene, 2,4-dinitrotoluene, 2,6-dinitrotoluene or industrial dinitrotoluene mixtures composed essentially of the last two isomers mentioned.
Aromatic nitro compounds used in particular preference are 2,4-dinitrotoluene or industrial mixtures thereof with up to 35 wt.%, based on the total mixture, of 2,6-dinitrotoluene. These industrial mixtures may also contain secondary quantities, i.e. up to a maximum of 6 wt.%, based on the total mixture, of 2,3-, 2,5- or 3,4-dinitrotoluene.
~hhe inherently known hydrogenation catalysts for nitro compounds are used for the process according to the invention. The catalysts, shaken in the solid form, adhering to supports, grids, packings or fabrics, may be arranged geometrically as required in such a way that the pressure drop is as low as possible, the distribution over the catalyst bed T o A 27 X1'1 is optimal, and the speed of the reaction mixture is high enough to absorb the heat of reaction. Highly suitable catalysts are, in particular, made of metals of the 8th subsidiary group of the periodic system of elements, which are used, for example, on support materials such as oxides of magnesium, aluminium titanium and/or nickel, including Raney-Nickel. Nickel catalysts are used in preference. Noble metal catalysts on a suitable support material such as, e.g., palladium on carbon, may also be used.
The catalysts are preferably in the pressed solid form, dumped on textured bases.
The process according to the invention is carried out preferably in such a way that - the circulation of the reaction mixture over a fixed bed or trickle bed is operated in such a way that the volumetric ratio of the mixture to the nitro compound introduced is 50 to 500, preferably 200 to 300, - the hydrogen feed is a self suction feed, i.e. the hydrogen gas collecting in the upper part of the reactor is mixed of its own accord back into the reaction mixture by the energy of the circulated mixture, - the operating pressure of the reactor system is maintained by feeding in fresh hydrogen from outside, - the volumetric ratio of the incoming hydrogen stream to the pumped mixture is 0.1 to 7, the hydrogen required being withdrawn from the gas chamber of the reactor and the hydrogen consumed during the reaction being replenished in any part of the system, the ratio of catalyst to nitro compound introduced is <20 kg/kgh and preferably 5 to 14 kg/kgh.
Due to the mixing of the aromatic nitro component with the recycled hydrogenated ronz~~m product (product loop), intensive mixing and distribution over the catalyst bed is obtained with the other process parameters. As a result, catalytic hydrogenation, optionally also solvent-free, of di- or polyaromatics is possible at high temperatures, so that steam at a pressure above atmospheric of more than 2 bar may be generated at the same time by removing heat from the system. Secondary reactions or the like occur only to a minor extent, if at all.
In order to regenerate the catalyst bed, the metered addition of the aromatic di- and/or polynitro compounds is interrupted, if necessary. In a simple manner, the catalyst may thus be regenerated by means of the product stream which continues to flow without a lengthy interruption of the process being required for said regeneration.
Optionally, the aromatic di- and/or polynitro compounds may be metered into the product stream preferably also in a solvent. Suitable solvents are aliphatic C, to C4 alcohols, particularly methanol, ethanol, isopropanol, t-butanol or cyclic ethers, particularly dioxane or tetrahydrofuran.
The process according to the invention may be carried out e.g. in a reaction system which is represented schematically in Figure 1 (trickle bed) or alternatively in Figure 2 (fixed bed). The numbers in these Figures have the following meaning:
1 ) Reactor 2) Catalyst bed 3) Pipe systems. Pump for recycling the reaction mixture 4) Heat exchanger for cooling the circulated reaction mixture 5) Cias cooler p0 6) Intake of circulating hydrogen Le A 32 613 7) Steam separator 8) Condensate The invention will be explained in more detail on the basis of the examples below without limiting its scope.
LeA32613-Examples Example 1 (compare Fig. I ) In an autoclave 1 (diameter 14 cm) with a trickle bed (catalyst 50 ml Ra-Nickel, pressed, cubic mouldings: 3 to 4 mm in diameter, 5 to 6 mm in height), 1,000 1/h of TDA/water mixture are pumped 3 from above via a heat exchanger 4. The hydrogen-containing, cooled gas 5 is pumped out of the reactor via an injector 4 by means of the liquid stream cooled from 180°C to 155°C. 5 kg/h of dinitrotoluene (70°C), liquid, are added before the hydrogen circulation. The hydrogen consumed by the reaction is added from above by fresh hydrogen in co-current. In accordance with the metered addition of the vitro compound, the TDA isomers and water of reaction are obtained stoichiometrically, selectively, in a >99% yield.
Example 2 (compare Fig. 2) In an autoclave 1 (diameter 14 cm) with a fixed bed (catalyst 50 ml as in Example 1), 1,000 1/h of TDA/water mixture are pumped from below via a heat exchanger 2.
Hydrogen-containing, cooled gas 5 is pumped out of the reactor via an injector 4 by means of the liquid stream cooled from 180°C to 155°C. 5 kg/h of dinitrotoluene (70°C), liquid, are added before the pump 3. The hydrogen consumed by the reaction is added from below by fresh hydrogen in co-current. In accordance with the metered addition of the vitro compound, the TDA isomers and water of reaction are obtained stoichiometrically, selectively, in a >99.2% yield.
Processes for the preparation of aromatic amines by catalytic hydrogenation of the nitro compounds on which they are based are known in large number (DE-A-2 135 155, DE-A-2 106 644, DE-A-4 435 839, EP-A-0 696 573 and WO 97/20 804).
Generally speaking, the industrial-scale catalytic hydrogenation of aromatic polynitro compounds in suspensions is carried out at low temperatures because there is a risk of uncontrolled secondary reactions during the hydrogenation of aromatic polynitro compounds at high temperatures. These secondary reactions may lead to the formation of unwanted by-products and hence to reductions in yield. Reactions involving hydrogenation of the nucleus, hydrogenolytic cleavage or the formation of high molecular weight, tar-like products may be mentioned by way of example in this connection. Explosive secondary reactions may also take place which are due to the highly exothermic course of the nitro group reaction and its high rate of reaction at relatively high temperatures.
When aromatic polynitro compounds are reacted with hydrogen, a considerable amount of heat is released. Advantageous hydrogenation processes are those in which the increased reaction energy does not have to be destroyed with an expenditure of energy but in which the reaction energy can be utilised economically in the form of steam production.
p0 Fouling and deposits of catalysts are observed time and again in the catalytic suspension processes. Product impurities, relatively poor hydrogenation yields and LeA32613 , _2_ high catalyst consumptions are often associated with this. The expenditure on cleaning and maintenance is considerable.
Thelen et al. (DE-A-2 135 154 and DE-A-2 135 155) have circumvented these disadvantages by the description of catalytic hydrogenation on a fixed bed. In spite of the advantageous arrangement of the catalyst in a fixed bed, the disadvantages are that the quantity of heat is removed in the reactor, the dimensions and structure of the reactor and the deposition of the catalyst in spinel form onto the cooling tubes are very expensive. The throughput of aromatic polynitro compounds is small. The removal of heat is problematic and the reaction must be carried out only at low temperatures.
The catalytic hydrogenation of aromatic vitro compounds on a fixed bed in a combination of two fixed bed reactors is described in WO 97/20 804 (Chambost et al.).
The division of the product quantities after the first reactor with simultaneous gas separation is problematic and expensive. Disadvantages of the process described here are the use of two reactors and the low reaction temperatures of up to 120°C.
Moreover, large quantities of solvents such as alcohols or ethers are used in some cases, the solvent having to be separated from the aromatic diamine after the reaction and optionally worked up.
The object was, therefore, to provide an improved process for the preparation of amines by hydrogenation of aromatic vitro compounds which makes it possible to operate without solvents or only with little solvent even at high temperatures without secondary reactions or fouling occurring.
The invention relates to a continuous process for the preparation of aromatic di- and/or polyamines by catalytic hydrogenation of the corresponding aromatic di- and/or polynitro compounds with hydrogen, in which, in a reactor with a catalytic fixed bed or trickle bed at a pressure between 5 and 100 bar and a reaction temperature from 100 to 220°C, rPe~~~~z a) the aromatic di- and/or polynitro compounds, optionally in the presence of a solvent, are introduced into a product stream comprising essentially recycled hydrogenated product, water and hydrogen, and b) a part of the product stream is removed continuously from the reactor system.
A pressure of 10 to 80 bar and an operating temperature of 150 to 200°C
are preferably maintained in the reactor.
The reactor used preferably has an external heat exchanger so that the heat of reaction produced can be used for steam generation.
The product discharge may take place at any place in the reactor system. The discharge takes place preferably after the external heat exchanger before pumping. The product stream removed from the reaction system is advantageously cooled to about 150 to 160°C.
Examples of aromatic nitro compounds used in preference are:
1,3-dinitrobenzene, 2,4-dinitrotoluene, 2,6-dinitrotoluene or industrial dinitrotoluene mixtures composed essentially of the last two isomers mentioned.
Aromatic nitro compounds used in particular preference are 2,4-dinitrotoluene or industrial mixtures thereof with up to 35 wt.%, based on the total mixture, of 2,6-dinitrotoluene. These industrial mixtures may also contain secondary quantities, i.e. up to a maximum of 6 wt.%, based on the total mixture, of 2,3-, 2,5- or 3,4-dinitrotoluene.
~hhe inherently known hydrogenation catalysts for nitro compounds are used for the process according to the invention. The catalysts, shaken in the solid form, adhering to supports, grids, packings or fabrics, may be arranged geometrically as required in such a way that the pressure drop is as low as possible, the distribution over the catalyst bed T o A 27 X1'1 is optimal, and the speed of the reaction mixture is high enough to absorb the heat of reaction. Highly suitable catalysts are, in particular, made of metals of the 8th subsidiary group of the periodic system of elements, which are used, for example, on support materials such as oxides of magnesium, aluminium titanium and/or nickel, including Raney-Nickel. Nickel catalysts are used in preference. Noble metal catalysts on a suitable support material such as, e.g., palladium on carbon, may also be used.
The catalysts are preferably in the pressed solid form, dumped on textured bases.
The process according to the invention is carried out preferably in such a way that - the circulation of the reaction mixture over a fixed bed or trickle bed is operated in such a way that the volumetric ratio of the mixture to the nitro compound introduced is 50 to 500, preferably 200 to 300, - the hydrogen feed is a self suction feed, i.e. the hydrogen gas collecting in the upper part of the reactor is mixed of its own accord back into the reaction mixture by the energy of the circulated mixture, - the operating pressure of the reactor system is maintained by feeding in fresh hydrogen from outside, - the volumetric ratio of the incoming hydrogen stream to the pumped mixture is 0.1 to 7, the hydrogen required being withdrawn from the gas chamber of the reactor and the hydrogen consumed during the reaction being replenished in any part of the system, the ratio of catalyst to nitro compound introduced is <20 kg/kgh and preferably 5 to 14 kg/kgh.
Due to the mixing of the aromatic nitro component with the recycled hydrogenated ronz~~m product (product loop), intensive mixing and distribution over the catalyst bed is obtained with the other process parameters. As a result, catalytic hydrogenation, optionally also solvent-free, of di- or polyaromatics is possible at high temperatures, so that steam at a pressure above atmospheric of more than 2 bar may be generated at the same time by removing heat from the system. Secondary reactions or the like occur only to a minor extent, if at all.
In order to regenerate the catalyst bed, the metered addition of the aromatic di- and/or polynitro compounds is interrupted, if necessary. In a simple manner, the catalyst may thus be regenerated by means of the product stream which continues to flow without a lengthy interruption of the process being required for said regeneration.
Optionally, the aromatic di- and/or polynitro compounds may be metered into the product stream preferably also in a solvent. Suitable solvents are aliphatic C, to C4 alcohols, particularly methanol, ethanol, isopropanol, t-butanol or cyclic ethers, particularly dioxane or tetrahydrofuran.
The process according to the invention may be carried out e.g. in a reaction system which is represented schematically in Figure 1 (trickle bed) or alternatively in Figure 2 (fixed bed). The numbers in these Figures have the following meaning:
1 ) Reactor 2) Catalyst bed 3) Pipe systems. Pump for recycling the reaction mixture 4) Heat exchanger for cooling the circulated reaction mixture 5) Cias cooler p0 6) Intake of circulating hydrogen Le A 32 613 7) Steam separator 8) Condensate The invention will be explained in more detail on the basis of the examples below without limiting its scope.
LeA32613-Examples Example 1 (compare Fig. I ) In an autoclave 1 (diameter 14 cm) with a trickle bed (catalyst 50 ml Ra-Nickel, pressed, cubic mouldings: 3 to 4 mm in diameter, 5 to 6 mm in height), 1,000 1/h of TDA/water mixture are pumped 3 from above via a heat exchanger 4. The hydrogen-containing, cooled gas 5 is pumped out of the reactor via an injector 4 by means of the liquid stream cooled from 180°C to 155°C. 5 kg/h of dinitrotoluene (70°C), liquid, are added before the hydrogen circulation. The hydrogen consumed by the reaction is added from above by fresh hydrogen in co-current. In accordance with the metered addition of the vitro compound, the TDA isomers and water of reaction are obtained stoichiometrically, selectively, in a >99% yield.
Example 2 (compare Fig. 2) In an autoclave 1 (diameter 14 cm) with a fixed bed (catalyst 50 ml as in Example 1), 1,000 1/h of TDA/water mixture are pumped from below via a heat exchanger 2.
Hydrogen-containing, cooled gas 5 is pumped out of the reactor via an injector 4 by means of the liquid stream cooled from 180°C to 155°C. 5 kg/h of dinitrotoluene (70°C), liquid, are added before the pump 3. The hydrogen consumed by the reaction is added from below by fresh hydrogen in co-current. In accordance with the metered addition of the vitro compound, the TDA isomers and water of reaction are obtained stoichiometrically, selectively, in a >99.2% yield.
Claims (9)
1. A continuous process for the preparation of aromatic di- and/or polyamines by catalytic hydrogenation of the corresponding aromatic di- and/or polynitro compounds with hydrogen, characterised in that, in a reactor with a catalytic fixed bed or trickle bed at a pressure between 5 and 100 bar and a reaction temperature from 100 to 220°C, a) the aromatic di- and/or polynitro compounds, optionally in the presence of a solvent, are introduced into a product stream comprising essentially recycled hydrogenated product, water and hydrogen, and b) a part of the product stream is removed continuously from the reactor system.
2. A process according to claim 1, characterised in that the aromatic di- or polynitro compound in the pure form is used as a mixture with the corresponding di- or polyamine and water.
3. A process according to claims 1 to 2, characterised in that the aromatic dinitro compound used is 2,4-dinitrotoluene or industrial mixtures thereof with 2,6-dinitrotoluene.
4. A process according to claims 1 to 3, characterised in that the volumetric ratio of the pumped, rapidly flowing mixture to the di- or polynitro compound introduced is 50 to 500.
5. A process according to claims 1 to 4, characterised in that the ratio of catalyst to nitro compound introduced is <20 kg/kgh, preferably 5 to 14 kg/kgh.
6. A process according to claims 1 to 5, characterised in that the catalyst bed is impinged either from above or from below with the recycled hydrogenated product.
7. A process according to claims 1 to 6, characterised in that solvents used are aliphatic C1 to C4 alcohols or cyclic ethers.
8. A process according to claim 7, characterised in that the solvent is used in a quantity of 0.1 to 40 wt.% of the reaction mixture.
9. A process according to claims 7 to 8, characterised in that the solvent is used in a quantity of 1 to 10 wt.% of the reaction mixture.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19745465A DE19745465A1 (en) | 1997-10-15 | 1997-10-15 | Continuous production of aromatic di- and/or polyamines by catalyzed hydrogenation using water, hydrogen, nitro-compound and recycled hydrogenation product |
| DE19745465.8 | 1997-10-15 | ||
| PCT/EP1998/006275 WO1999019292A1 (en) | 1997-10-15 | 1998-10-02 | Continuous method for producing aromatic amines |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2306935A1 true CA2306935A1 (en) | 1999-04-22 |
Family
ID=7845567
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002306935A Abandoned CA2306935A1 (en) | 1997-10-15 | 1998-10-02 | Continuous method for producing aromatic amines |
Country Status (11)
| Country | Link |
|---|---|
| EP (1) | EP1023261B1 (en) |
| KR (1) | KR100566450B1 (en) |
| CN (1) | CN1165513C (en) |
| AU (1) | AU9748298A (en) |
| BR (1) | BR9813052A (en) |
| CA (1) | CA2306935A1 (en) |
| DE (2) | DE19745465A1 (en) |
| ES (1) | ES2174497T3 (en) |
| HK (1) | HK1033304A1 (en) |
| TW (1) | TW443998B (en) |
| WO (1) | WO1999019292A1 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| IT1318602B1 (en) * | 2000-06-29 | 2003-08-27 | Enichem Spa | PROCEDURE FOR THE PRODUCTION OF AROMATIC AMINES. |
| US6521791B1 (en) * | 2001-11-09 | 2003-02-18 | Air Products And Chemicals, Inc. | Process for regenerating a monolith hydrogenation catalytic reactor |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2135155A1 (en) * | 1971-07-14 | 1973-02-22 | Bayer Ag | Catalyst for redn of nitro cpds - comprising palladium on an aluminium spinel support |
| DE3315191A1 (en) * | 1983-04-27 | 1984-10-31 | Bayer Ag, 5090 Leverkusen | METHOD FOR THE CONTINUOUS PRODUCTION OF AROMATIC DIAMINES WITH SIMULTANEOUS GENERATION OF STEAM |
| DE4323687A1 (en) * | 1993-07-15 | 1995-01-19 | Bayer Ag | Continuous process for the production of aromatic amines |
| DE4428017A1 (en) * | 1994-08-08 | 1996-02-15 | Bayer Ag | Process for the preparation of aromatic amines |
| FR2741877B1 (en) * | 1995-12-01 | 1998-02-13 | Rhone Poulenc Chimie | PROCESS FOR HYDROGENATION OF AROMATIC NITER COMPOUNDS |
-
1997
- 1997-10-15 DE DE19745465A patent/DE19745465A1/en not_active Withdrawn
-
1998
- 1998-09-25 TW TW087115933A patent/TW443998B/en not_active IP Right Cessation
- 1998-10-02 CA CA002306935A patent/CA2306935A1/en not_active Abandoned
- 1998-10-02 AU AU97482/98A patent/AU9748298A/en not_active Abandoned
- 1998-10-02 KR KR1020007003984A patent/KR100566450B1/en not_active IP Right Cessation
- 1998-10-02 BR BR9813052-8A patent/BR9813052A/en not_active IP Right Cessation
- 1998-10-02 EP EP98951488A patent/EP1023261B1/en not_active Expired - Lifetime
- 1998-10-02 WO PCT/EP1998/006275 patent/WO1999019292A1/en active IP Right Grant
- 1998-10-02 ES ES98951488T patent/ES2174497T3/en not_active Expired - Lifetime
- 1998-10-02 DE DE59803298T patent/DE59803298D1/en not_active Expired - Lifetime
- 1998-10-02 CN CNB988102986A patent/CN1165513C/en not_active Expired - Fee Related
-
2001
- 2001-06-06 HK HK01103910A patent/HK1033304A1/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| ES2174497T3 (en) | 2002-11-01 |
| TW443998B (en) | 2001-07-01 |
| CN1165513C (en) | 2004-09-08 |
| KR20010015758A (en) | 2001-02-26 |
| AU9748298A (en) | 1999-05-03 |
| EP1023261B1 (en) | 2002-03-06 |
| HK1033304A1 (en) | 2001-08-24 |
| BR9813052A (en) | 2000-08-15 |
| CN1276780A (en) | 2000-12-13 |
| EP1023261A1 (en) | 2000-08-02 |
| DE59803298D1 (en) | 2002-04-11 |
| WO1999019292A1 (en) | 1999-04-22 |
| DE19745465A1 (en) | 1999-04-22 |
| KR100566450B1 (en) | 2006-03-31 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| FZDE | Dead |