The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 20, 1990
Filed:
Jan. 09, 1989
Otto Immel, Krefeld, DE;
Hans-Helmut Schwarz, Krefeld, DE;
Bayer Aktiengesellschaft, Leverkusen, DE;
Abstract
Diphenylamine which is unsubstituted or substituted by alkyl or alkoxy groups can be prepared by treating appropriately substituted dicyclohexylamine with 1-10 bar of H.sub.2 over catalysts containing 0.05-5% by weight of rhodium at 250.degree.-450.degree. C. In addition to rhodium, the catalysts contain at least one other platinum metal from the group consisting of palladium, platinum and iridium on a support containing the noble metals in a total amount of 0.05-5% by weight, the percentage by weight of rodium with respect to all noble metals being 10-90%, and furthermore containing additives of 1-6% by weight of an alkali metal hydroxide and 1-6% by weight of an alkali metal sulphate. All percentages are based on the total weight of the catalyst.