Claims
- 1. A process for the preparation of a mixture of optionally substituted cyclohexylamine and optionally substituted dicyclohexylamine by catalytic hydrogenation of optionally substituted aniline on a supported noble metal catalyst, wherein a catalyst containing ruthenium, palladium or a mixture of both on a support containing niobic acid Nb.sub.2 O.sub.5.nH.sub.2 O, tantalic acid Ta.sub.2 O.sub.5.nH.sub.2 O or a mixture of both, which contains the noble metal(s) in a total amount from 0.05 to 5% by weight and in the case of an Ru/Pd mixture, contains both metals in a weight ratio of 1:9-9:1, all percentages being based on the total weight of the catalyst is employed and the reaction is carried out at a temperature in the range from 100.degree. to 340.degree. C. and at a pressure of 100 to 500 bar.
- 2. The process of claim 1, wherein the reaction is carried out in the range of 130.degree. to 240.degree. C.
- 3. The process of claim 1, wherein the reaction is carried out at a pressure of 100 to 400 bar.
- 4. The process of claim 1, wherein the reaction is carried out continuously in the liquid phase on a fixed catalyst packing and a catalyst loading of 0.05-3 kg of optionally substituted aniline per liter of catalyst and per hour is set.
- 5. The process of claim 4, wherein a catalyst loading of 0.1-2 kg of optionally substituted aniline per liter of catalyst and per hour is set.
- 6. The process of claim 1, wherein an aniline of the formula ##STR3## is employed in which R.sup.1 and R.sup.2 independently of one another denote hydrogen, C.sub.1 -C.sub.4 -alkyl or C.sub.1 -C.sub.4 -alkoxy.
- 7. The process of claim 1, wherein, as the substituted aniline, the cyclohexylideneaniline of the formula ##STR4## is employed, in which R.sup.1 and R.sup.2 independently of one another denote hydrogen, C.sub.1 -C.sub.4 -alkyl or C.sub.1 -C.sub.4 -alkoxy.
- 8. The process of claim 7, wherein the cyclohexylideneaniline is employed in the form of a mixture of the underlying, optionally substituted cyclohexanone with the underlying, optionally substituted aniline.
- 9. The process of claim 3, wherein the reaction is carried out in the range of 130.degree. to 240.degree. C., the catalyst consists essentially of palladium on said support, the reaction is carried out continuously in the liquid phase on a fixed catalyst packing and a catalyst loading of 0.1-2 kg of optionally substituted aniline per liter of catalyst and per hour, and the aniline subjected to hydrogenation is of the formula ##STR5## in which R.sup.1 and R.sup.2 independently of one another denote hydrogen, C.sub.1 -C.sub.4 -alkyl or C.sub.1 -C.sub.4 -alkoxy.
Priority Claims (1)
Number |
Date |
Country |
Kind |
4106543 |
Mar 1991 |
DEX |
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Parent Case Info
This application is a continuation of application Ser. No. 922,258, filed Jul. 30, 1992, now abandoned, which is a division of application Ser. No. 840,355, filed Feb. 24, 1992, now abandoned.
US Referenced Citations (4)
Number |
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Date |
Kind |
4487966 |
Fiedler et al. |
Dec 1984 |
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4503251 |
Gray et al. |
Mar 1985 |
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4666881 |
Wood et al. |
May 1987 |
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4952549 |
Immel et al. |
Aug 1990 |
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Foreign Referenced Citations (1)
Number |
Date |
Country |
227868 |
Jul 1987 |
EPX |
Divisions (1)
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Number |
Date |
Country |
Parent |
840355 |
Feb 1992 |
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Continuations (1)
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Number |
Date |
Country |
Parent |
922258 |
Jul 1992 |
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