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:
Jan. 18, 1983
Filed:
Oct. 20, 1981
Dieter Stockburger, Gruenstadt, DE;
Wilhelm Schultz, Gruenstadt, DE;
Johannes E Schmidt, Ludwigshafen, DE;
Friedrich Wirth, Ludwigshafen, DE;
Herwig Hoffmann, Frankenthal, DE;
Bernhard Holzknecht, Ellerstadt, DE;
Klaus Wintermantel, Weinheim-Oberflockenbach, DE;
BASF Aktiengesellschaft, Ludwigshafen, DE;
Abstract
A process for the preparation of phthalic anhydride (PA) of catalytic oxidation of naphthalene or o-xylene with air, a preheated mixture of air and naphthalene or o-xylene being passed into a reactor charged with the catalyst, and the reaction gas leaving the reactor being passed through a separator in which the PA is separated out as a solid, in which process the air fed to the reactor is preheated, before or after the admixture of naphthalene or of o-xylene, by using it to cool the reaction gas in the PA separator.