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:
Apr. 09, 1985
Filed:
Jan. 30, 1984
Applicant:
Inventors:
Dietrich Tonnius, Mannheim, DE;
Wolfgang Weiss, Neckarhausen, DE;
Winfried Orth, Hassloch, DE;
Heinrich Miele, Weinheim, DE;
Emmerich Pastorek, Hemsbach, DE;
Assignee:
Rutgerswerke Aktiengesellschaft, Frankfurt, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
2603 / ;
Abstract
Improvement of the yield and purity of phenanthrenequinone during its production by oxidation of phenanthrene by means of chromic acid in a sulfuric acidic medium is achieved by preparing a dispersion made up of phenanthrene, alkali dichromate and water at 95.degree.-100.degree. C., cooling said dispersion down to 80.degree.-85.degree. C. and carrying out the oxidation reaction under cooling and portion-wise addition of concentrated sulfuric acid in a temperature range between 80.degree. and 85.degree. C.