Patent US3935264A successfully refreshed from Google Patents.
US3935264A
Expired / Lapsed
US
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Hydrogenation of dinitrotoluene to toluene diamine
Assignee: Olin Corp
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Filing: 1974-06-19
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Granted: 1976-01-27
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Expires: 1994-06-19
Abstract
Abstract An improved process is disclosed for the hydrogenation of dinitrotoluene to toluene diamine in the presence of an aliphatic alcohol solvent. Aimed at preventing the formation of N-alkyl toluene diamine by-product, the improvement resides in carrying out the hydrogenation reaction in the presence of a small proportion of carbon monoxide.
Inventors
- 👤 Sudhir K. Bhutani
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 05:25
CPC Classifications
C; C07; C07C; C07C209/00; C07C209/30; C07C209/32; C07C209/36
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
67 words
In a process for preparing toluene diamine which comprises reacting dinitrotoluene with hydrogen in the presence of an aliphatic alcohol solvent and a hydrogenation catalyst comprised of nickel, platinum or palladium, the improvement which comprises carrying out said reaction in the presence of a proportion of carbon monoxide ranging from about 0.1 to about 10 percent by volume based on the volume of hydrogen which is used.
Claim 2
Dependent Claim
67 words
In a process for preparing toluene diamine which comprises reacting dinitrotoluene with hydrogen in the presence of an aliphatic alcohol solvent and a hydrogenation catalyst comprised of nickel, platinum or palladium, the improvement which comprises carrying out said reaction in the presence of a proportion of carbon monoxide ranging from about 0.1 to about 10 percent by volume based on the volume of hydrogen which is used.
Claim 3
Dependent Claim
18 words
The process of claim 1 wherein said catalyst is comprised of Raney nickel and said solvent is methanol.
Claim 4
Dependent Claim
17 words
The process of claim 1 wherein said alcohol is an unsubstituted alkyl monoalcohol having 1-8 carbon atoms.
Claim 5
Dependent Claim
28 words
The process of claim 3 wherein said proportion of carbon monoxide ranges from about 0.3 to about 6.0 percent by volume based on the volume of said hydrogen.
Claim 6
Dependent Claim
23 words
The process of claim 4 wherein said dinitrotoluene is employed in the form of a non-vicinal isomer or a mixture of nonvincinal isomers.
Claim 7
Dependent Claim
13 words
The process of claim 5 wherein said catalyst is comprised of Raney nickel.
Claim 8
Dependent Claim
12 words
The process of claim 6 wherein said alcohol has 1-4 carbon atoms.--
Claim 9
Dependent Claim
15 words
The process of claim 7 wherein said dinitrotoluene is 2,4-dinitrotoluene, 2,6-dinitrotoluene or a mixture thereof.
Claim 10
Dependent Claim
14 words
The process of claim 8 wherein a reaction temperature of about 90°-150°C is employed.--
Claim 11
Dependent Claim
10 words
The process of claim 9 wherein said solvent is methanol.
Claim 12
Dependent Claim
22 words
The process of claim 10 wherein said carbon monoxide is combined with said hydrogen before the latter is reacted with said dinitrotoluene.
Claim 13
Dependent Claim
17 words
The process of claim 11 wherein said hydrogen is supplied at a pressure of about 100-1,000 psig.
Claim 14
Dependent Claim
26 words
The process of claim 12 wherein said methanol is employed in a proportion of about 100-1,000 parts per every 100 parts by weight of said dinitrotoluene.
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) | 1979-01-26 | 1979-07-28 | 1980-01-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-01-26 | 1983-07-28 | 1984-01-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-01-26 | 1987-07-28 | 1988-01-27 | $7700.00 | Window Closed / Lapsed |