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. 29, 2008
Filed:
Sep. 04, 2004
Randolf Hugo, Dirmstein, DE;
Sabine Jourdan, Mannheim, DE;
Kirsten Wenz, Mannheim, DE;
Thomas Preiss, Weisenheim Am Sand, DE;
Alexander Weck, Freinsheim, DE;
Randolf Hugo, Dirmstein, DE;
Sabine Jourdan, Mannheim, DE;
Kirsten Wenz, Mannheim, DE;
Thomas Preiss, Weisenheim Am Sand, DE;
Alexander Weck, Freinsheim, DE;
BASF Aktiengesellschaft, Ludwigshafen, DE;
Abstract
A process for preparing xylylenediamine, comprising the steps of ammoxidizing xylene to phthalonitrile by contacting the vaporous product of this ammoxidation stage directly with a liquid organic solvent (quench), removing products having a boiling point higher than phthalonitrile (high boilers) from the resulting quench solution or suspension and hydrogenating the phthalonitrile, wherein the organic solvent used for the quench is N-methyl-2-pyrrolidone (NMP), after the removal of the high boilers and before the hydrogenation, there is a partial or complete removal of the NMP and/or of products having a boiling point lower than phthalonitrile (low boilers) and the phthalonitrile for the hydrogenation step is dissolved or suspended in an organic solvent or in liquid ammon.