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:
Dec. 02, 2014
Filed:
Apr. 13, 2011
Stefan Altwasser, Wachenheim, DE;
Jürgen Zühlke, Speyer, DE;
Hao Chen, Pictorial Garden, CN;
Cornelia Katharina Dobner, Ludwigshafen, DE;
Frank Rosowski, Mannheim, DE;
Stefan Altwasser, Wachenheim, DE;
Jürgen Zühlke, Speyer, DE;
Hao Chen, Pictorial Garden, CN;
Cornelia Katharina Dobner, Ludwigshafen, DE;
Frank Rosowski, Mannheim, DE;
BASF SE, , DE;
Abstract
In a process for controlling a gas phase oxidation reactor for preparation of phthalic anhydride, by passing a gas stream which comprises an aromatic hydrocarbon and molecular oxygen through a multitude of reaction tubes arranged in the gas phase oxidation reactor, each of which comprises a bed of at least one catalyst and the temperature of which can be controlled by means of a heat transfer medium, at least one control parameter is measured and correcting interventions for control of the control parameter are determined, the at least one control parameter comprising the phthalic anhydride yield and the correcting parameter used being the temperature of the heat carrier medium. Over at least 90% of the lifetime of the catalyst, the change in the correcting parameter is limited to a maximum of 0.5 K within a period of 30 days. In this way, the cumulated phthalic anhydride yield over the lifetime of the catalyst is maximized.