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. 09, 2004
Randolf Hugo, Dirmstein, DE;
Kirsten Wenz, Mannheim, DE;
Sabine Jourdan, Mannheim, DE;
Thomas Preiss, Weisenheim, DE;
Randolf Hugo, Dirmstein, DE;
Kirsten Wenz, Mannheim, DE;
Sabine Jourdan, Mannheim, DE;
Thomas Preiss, Weisenheim, DE;
BASF Aktiengesellschaft, Ludwigshafen, DE;
Abstract
A process for preparing xylylenediamine by continuously hydrogenating liquid phthalonitrile over a heterogeneous catalyst in the presence of liquid ammonia in a reactor, in which a portion of the reactor effluent is recycled as a liquid circulation stream continuously to the reactor inlet (circulation mode), in which a stream of a phthalonitrile melt in liquid form is conducted by means of a mixer unit into the circulation stream around the hydrogenation reactor, the phthalonitrile conversion in the reactor on single pass being greater than 99%, and the circulation stream consisting to an extent of greater than 93% by weight of liquid ammonia and xylylenediamine and not comprising any further solvent for phthalonitrile.