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:
Mar. 15, 2016
Filed:
Jul. 23, 2013
Bayer Materialscience Ag, Leverkusen, DE;
Thomas Knauf, Dormagen, DE;
Michael Merkel, Dusseldorf, DE;
Bayer MaterialScience AG, Leverkusen, DE;
Abstract
The present invention provides a continuous process for the production of nitrobenzene by nitration of benzene with mixtures of sulfuric and nitric acid using a stoichiometric excess of benzene, in which the content of aliphatic organic compounds in the feed benzene during the start-up period of the production plant is always maintained at less than 1.5 wt. %, based on the total mass of the feed benzene. This is achieved either by mixing the feed benzene comprising recycled unreacted benzene (recycled benzene) and benzene newly supplied to the reaction (fresh benzene) in appropriate quantitative ratios during the start-up period, depending on the purity of the two streams, or by completely omitting the recycling of unreacted benzene during the start-up period, i.e. the feed benzene consists only of benzene newly supplied to the reaction.