US4057581A
Expired / Lapsed
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Process for preparing diphenylamines
Assignee: Bayer AG
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Filing: 1976-04-15
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Granted: 1977-11-08
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Expires: 1996-04-15
Abstract
Abstract Diphenylamines having the formula: ##STR1## wherein R 1 , R 2 , R 3 and R 4 are the same or different and are hydrogen, alkyl with up to 4 C atoms or alkoxy with up to 4 C atoms, Are prepared by catalytically dehydrogenating the corresponding wholly or partially hydrogenated diphenylamines. The catalyst used is a nickel/chromium catalyst containing manganese and/or aluminum and/or copper and/or sulphates of the alkali metals or alkaline earth metals.
Inventors
- 👤 Hermann-Dieter Krall
- 👤 Oskar Weissel
- 👤 Hans-Helmut Schwarz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 03:57
CPC Classifications
C; C07; C07C; C07C209/00; C07C209/68; B; B01; B01J; B01J23/00; B01J23/70; B01J23/76; B01J23/84; B01J23/85; B01J23/86
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
86 words
In a process for preparing a diphenylamine having the formula ##STR4## wherein R 1 , R 2 , R 3 and R 4 are the same or different and are hydrogen, alkyl containing 1 to 4 carbon atoms or alkoxy containing 1 to 4 carbon atoms by catalytic dehydrogenation of a dicyclohexylamine, N-cyclohexylidene-cyclohexylamine, N-cyclohexyl-aniline or N-cyclohexylidene-aniline in the presence of a nickel/chromium catalyst the improvement which comprises employing as the nickel/chromium catalyst one which contains at least one member of the group manganese, aluminum and copper.
Claim 2
Dependent Claim
86 words
In a process for preparing a diphenylamine having the formula ##STR4## wherein R 1 , R 2 , R 3 and R 4 are the same or different and are hydrogen, alkyl containing 1 to 4 carbon atoms or alkoxy containing 1 to 4 carbon atoms by catalytic dehydrogenation of a dicyclohexylamine, N-cyclohexylidene-cyclohexylamine, N-cyclohexyl-aniline or N-cyclohexylidene-aniline in the presence of a nickel/chromium catalyst the improvement which comprises employing as the nickel/chromium catalyst one which contains at least one member of the group manganese, aluminum and copper.
Claim 3
Dependent Claim
23 words
A process according to claim 1 wherein an N-cyclohexylidene-aniline is reacted and the same is present in admixture with N-cyclohexylidene-cyclohexylamine, dicyclohexylamine or N-cyclohexylaniline.
Claim 4
Dependent Claim
48 words
Process of claim 1 wherein the nickel/chromium catalyst contains at least one member of the group aluminum and copper, the ratio by weight of the metals nickel, chromium, aluminum and copper to one another being 40 to 60; 6.8 to 17.5; 1.5 to 8.0; 0.05 to 1.0, respectively.
Claim 5
Dependent Claim
34 words
Process of claim 1 wherein the catalyst is nickel, chromium, aluminum and copper in a weight ratio of the metals of 40 to 60; 6.8 to 17.1; 1.6 to 8.0; 0.05 to 1.0, respectively
Claim 6
Dependent Claim
19 words
Process of claim 4 wherein the metallic nickel content in the catalyst is 10 to 35 percent by weight.
Claim 7
Dependent Claim
19 words
Process of claim 4 wherein the metallic nickel content in the catalyst is 35 to 45 percent by weight.
Claim 8
Dependent Claim
47 words
Process of claim 1 wherein nickel/chromium catalyst contains at least one member of the group manganese and alumium, the ratios by weight of the metals nickel, chromium, manganese and aluminum to one another being 10 to 50; 4 to 15; 1 to 30; 0 to 5, respectively.
Claim 9
Dependent Claim
14 words
Process of claim 1 carried out in temperature range from 250° to 400° C.
Claim 10
Dependent Claim
13 words
Process of claim 8 wherein the temperature range is 280° to 370° C.
Claim 11
Dependent Claim
9 words
Process of claim 1 carried out at atmospheric pressure.
Claim 12
Dependent Claim
15 words
Process of claim 1 carried out in a pressure range of 0.1 to 3.0 bars.
Claim 13
Dependent Claim
13 words
Process of claim 1 carried out in the presence of a gaseous diluent.
Claim 14
Dependent Claim
16 words
Process of claim 12 wherein in gaseous diluent is hydrogen, methane, natural gas or dry nitrogen.
Claim 15
Dependent Claim
25 words
Process of claim 12 wherein the gaseous diluent is used in amount of 0.1 to 10 mols per mol of nitrogen in the starting material.
Claim 16
Dependent Claim
23 words
Process of claim 14 wherein the amount of gaseous diluent is 1.0 to 5.0 mols per mol of nitrogen in the starting material.
Claim 17
Dependent Claim
26 words
Process of claim 1 wherein the reaction is carried out at a catalyst load of 0.05 g of starting material per ml of catalyst per hour.
Claim 18
Dependent Claim
21 words
Process of claim 16 wherein the load is 0.1 to 0.4 g of starging material per ml. of catalyst per hour.
Claim 19
Dependent Claim
21 words
Process of claim 16 wherein the load is 0.2 to 0.3 g of starting material per ml. of catalyst per hour.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-11-07 | 1981-05-09 | 1981-11-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-11-07 | 1985-05-09 | 1985-11-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-11-07 | 1989-05-09 | 1989-11-08 | $7700.00 | Window Closed / Lapsed |