Patent EP0335336A2 successfully refreshed from Google Patents.
EP0335336A2
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Catalytic hydrogenation of crude methylene bridged polyphenylamines to produce polycyclohexylamines
Assignee: Air Products and Chemicals Inc
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Filing: 1989-03-28
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Granted: —
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Expires: 2009-03-28
Abstract
Abstract This invention relates to an improved process for the catalytic hydrogenation of methylene bridged polyphenylamines using rhodium as the catalyst to produce the methylene bridged polycyclohexylamine counterparts. The improvement for hydrogenating crude methylene bridged polyphenylamines, containing polyphenylamine oligomers and trace amounts of impurities, such as the formamide of the methylene bridged polyphenylamines, comprises contacting the crude polyphenylamine feed with a hydrogenation catalyst, other than rhodium, and one which is not a catalyst poison to rhodium, under conditions sufficient to at least partially hydrogenate the polyphenylamine mixture and then effecting hydrogenation of the methylene bridged polyphenylamine to the polycyclohexylamine counterpart in the presence of a rhodium catalyst. The pretreatment of the crude methylene bridged polyphenylamine feed apparently destroys the formamide derivatives and possibly other trace impurities in the mixture and thereby prevents rapid deactivation of the rhodium catalyst during hydrogenation of the aromatic ring.
Inventors
- 👤 Gamini Ananda Vedage
- 👤 William Weldon Henderson
- 👤 Bernard Allen Toseland
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 09:51
CPC Classifications
C; C07; C07C; C07C209/00; C07C209/68; C07C209/70; C07C209/72
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
114 words
In a process for the hydrogenation of a crude methylene bridged polyphenylamine to produce the corresponding methylene bridged polycyclohexylamine counterpart in the presence of a rhodium hydrogenation catalyst at a temperature and for time sufficient to effect hydrogenation of the phenyl ring to the cyclohexyl ring, the improvement which comprises: pretreating the crude methylene bridged polyphenylamine feed via an initial hydrogenation in the presence of hydrogen and a hydrogenation catalyst, other than rhodium under conditions sufficient to at least partially hydrogenate the feed, said hydrogenation catalyst being non-poisonous to rhodium under said hydrogenation conditions, and then catalytically hydrogenating the methylene bridged-polyphenylamine in a secondary hydrogenation zone for producing the corresponding methylene bridged polycyclohexylamine counterpart.
Claim 2
Dependent Claim
114 words
In a process for the hydrogenation of a crude methylene bridged polyphenylamine to produce the corresponding methylene bridged polycyclohexylamine counterpart in the presence of a rhodium hydrogenation catalyst at a temperature and for time sufficient to effect hydrogenation of the phenyl ring to the cyclohexyl ring, the improvement which comprises: pretreating the crude methylene bridged polyphenylamine feed via an initial hydrogenation in the presence of hydrogen and a hydrogenation catalyst, other than rhodium under conditions sufficient to at least partially hydrogenate the feed, said hydrogenation catalyst being non-poisonous to rhodium under said hydrogenation conditions, and then catalytically hydrogenating the methylene bridged-polyphenylamine in a secondary hydrogenation zone for producing the corresponding methylene bridged polycyclohexylamine counterpart.
Claim 3
Dependent Claim
66 words
The process of Claim 1 wherein said methylene bridged-polyphenyl amines are represented by the formula wherein R is H, C₁₋₆ alkyl, C-O-R₃; where R₃ is C₁₋₄ alkyl, CH₂NH₂, R₁ and R₂, H or C₁₋₆ alkyl, x is 1-4 y is 0 to 2 with the sum being at least 1, provided x + y is not greater than 5, and z is from 0 to 3.
Claim 4
Dependent Claim
18 words
The process of Claim 2 wherein said initial hydrogenation is carried out using ruthenium as the hydrogenation catalyst.
Claim 5
Dependent Claim
29 words
The process of Claim 3 wherein said initial hydrogenation is carried out at at temperature from 130 to 220°C and for a time from about 10 to 120 minutes.
Claim 6
Dependent Claim
29 words
The process of Claim 4 wherein the ruthenium, as metal, is present in an amount of from 0.0005 to 10% by weight as metal of the methylene bridged polyphenylamine.
Claim 7
Dependent Claim
15 words
The process of Claim 5 wherein each x is 1 and each y is 1.
Claim 8
Dependent Claim
11 words
The process of Claim 6 wherein R₁ and R₂ are hydrogen.
Claim 9
Dependent Claim
11 words
The process of Claim 7 wherein R is hydrogen or methyl.
Claim 10
Dependent Claim
9 words
The process of Claim 8 wherein z is 0.
Claim 11
Dependent Claim
9 words
The process of Claim 9 wherein R is hydrogen.
Claim 12
Dependent Claim
45 words
The process of Claim 10 wherein the catalytic hydrogenation of the methylene bridged polyphenylamine to methylene bridged polycyclohexylamine is carried out using rhodium where the rhodium is present in an amount of from 0.001 to 10% by weight as metal of the methylene bridged polyphenylamine.
Claim 13
Dependent Claim
35 words
The process of Claim 11 wherein ruthenium is added to the rhodium in the secondary hydrogenation zone and the ratio of rhodium to ruthenium is from about 2-12 weight parts rhodium per weight part ruthenium.
Claim 14
Dependent Claim
137 words
In a process for catalytically hydrogenating a crude methylene bridged polyphenylamine feed containing oligomers and trace impurities including the formamide of the methylene bridged polyphenylamine wherein the catalytic hydrogenation is carried out in the presence of hydrogen utilizing a rhodium containing hydrogenation catalyst, which comprises: initially hydrogenating the crude methylene bridged polyphenylamine in the presence of a hydrogenation catalyst non-poisonous to rhodium for a time and a temperature sufficient to destroy said formamide of the methylene bridged polyphenylamine contained in the feed but insufficient for effecting complete hydrogenation of the methylene bridged polyphenylamine to methylene bridged polycyclohexylamine; and then, contacting the initially hydrogenated methylene bridged polyphenylamine feed with hydrogen in the presence of rhodium in a secondary hydrogenation zone under hydrogenation conditions sufficient to effect conversion of the methylene bridged polyphenylamine to its methylene bridged polycyclohexylamine counterpart.
Claim 15
Dependent Claim
137 words
In a process for catalytically hydrogenating a crude methylene bridged polyphenylamine feed containing oligomers and trace impurities including the formamide of the methylene bridged polyphenylamine wherein the catalytic hydrogenation is carried out in the presence of hydrogen utilizing a rhodium containing hydrogenation catalyst, which comprises: initially hydrogenating the crude methylene bridged polyphenylamine in the presence of a hydrogenation catalyst non-poisonous to rhodium for a time and a temperature sufficient to destroy said formamide of the methylene bridged polyphenylamine contained in the feed but insufficient for effecting complete hydrogenation of the methylene bridged polyphenylamine to methylene bridged polycyclohexylamine; and then, contacting the initially hydrogenated methylene bridged polyphenylamine feed with hydrogen in the presence of rhodium in a secondary hydrogenation zone under hydrogenation conditions sufficient to effect conversion of the methylene bridged polyphenylamine to its methylene bridged polycyclohexylamine counterpart.
Claim 16
Dependent Claim
66 words
The process of Claim 13 wherein said methylene bridged-polyphenyl amines are represented by the formula wherein R is H, C₁₋₆ alkyl, C-O-R₃; where R₃ is C₁₋₄ alkyl, CH₂NH₂, R₁ and R₂, H or C₁₋₆ alkyl, x is 1-4 and y is 0 to 2 with the sum being at least 1, x + y is not greater than 5, and z is from 0 to 3.
Claim 17
Dependent Claim
18 words
The process of Claim 14 wherein the initial hydrogenation is carried out using ruthenium as the hydrogenation catalyst.
Claim 18
Dependent Claim
27 words
The process of Claim 15 wherein the ruthenium is present in an amount of from 0.0005 to 10% by weight as metal of the methylene bridged polyphenylamine.
Claim 19
Dependent Claim
15 words
The process of Claim 16 wherein each x is 1 and each y is 1.
Claim 20
Dependent Claim
11 words
The process of Claim 17 wherein R₁ and R₂ are hydrogen.
Claim 21
Dependent Claim
11 words
The process of Claim 18 wherein R is hydrogen or methyl.
Claim 22
Dependent Claim
9 words
The process of Claim 19 wherein z is 0.
Claim 23
Dependent Claim
9 words
The process of Claim 20 wherein R is hydrogen.
Claim 24
Dependent Claim
26 words
The process of Claim 21 wherein the rhodium-containing catalyst system in the secondary hydrogenation zone comprises from about 1-12 weight parts rhodium per weight part ruthenium.
Claim 25
Dependent Claim
27 words
The process of Claim 22 wherein said rhodium is present in an amount to provide from about 0.001 to 10% metal by weight of the aromatic amine.
Claim 26
Dependent Claim
30 words
The process of Claim 16 wherein the aromatic amine is 3,3′-di- tert -butyl-4,4′-diaminodi-phenylmethane and the rhodium containing catalyst contains from 1 to 12 weight parts rhodium per weight part ruthenium.
Claim 27
Dependent Claim
29 words
The process of Claim 16 wherein the aromatic amine is 3,3′-dimethyl-5,5′-di- tert -butyl-4,4′-diaminodi-phenylmethane and the rhodium-containing catalyst contains from 1 to 12 weight parts rhodium per weight part ruthenium.
References Cited (Backward Citations)
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