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:
May. 26, 1998
Filed:
Sep. 15, 1995
Heinrich Hermann, Koln, DE;
Jurgen Gebauer, Troisdorf, DE;
Josef Meissner GmbH & Co., Koln, DE;
Abstract
A process for the removal and recovery of nitric acid, sulphuric acid and nitrous oxide (NO.sub.x) from crude dinitrotoluene (DNT) obtained by nitrating with a nitrating acid, a benzene derivative selected from the group consisting of tolulene or mononitrotoluene (after separation from the dinitrotoluene from the nitrating acid, wherein the crude dinitrotoluene is extracted in a plurality of steps whereby a dilute aqueous solution of nitric, sulfuric and nitrous acids countercurrently contacts the crude dinitrotoluene, the volume ratio of the dinitrotoluene to the aqueous solution being between 1:3 and 10:1, the extraction steps resulting in the formation of an aqueous extract which is blended directly into the nitrating acid for re-use in the acid nitration of the benzene derivative.