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. 02, 2013
Filed:
Jul. 08, 2008
Philippe Marion, Vernaison, FR;
Philippe Marion, Vernaison, FR;
Vencorex France, Saint-Priest, FR;
Abstract
The present invention relates to a process for preparing dinitrotoluene. The process of the invention for preparing dinitrotoluene from mononitrotoluene, which comprises carrying out a mononitrotoluene nitration reaction using a nitrating mixture comprising nitric acid, sulphuric acid and water resulting in a two-phase medium and separating the organic and aqueous phases of said two-phase medium, is characterized in that the mononitrotoluene nitration is carried out using a nitrating mixture comprising at most 10% by weight of water resulting in a two-phase medium, in that the organic and aqueous phases of said two-phase medium are separated, and in that the aqueous phase derived from the separating operation is recycled, at the end of the mononitrotoluene nitration reaction and before the separation of the organic and aqueous phases, such that the weight ratio of the aqueous phase to the organic phase is at least equal to 1.2.