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. 26, 2010
Filed:
Dec. 16, 2003
Alfred Oftring, Bad Duerkheim, DE;
Gerold Braun, Ludwigshafen, DE;
Alfred Oftring, Bad Duerkheim, DE;
Gerold Braun, Ludwigshafen, DE;
BASF Aktiengesellschaft, Ludwigshafen, DE;
Abstract
The present invention relates to a process for preparing 3-cyano-3,5,5-trimethylcyclohexanone (isophoronenitrile) by reacting isophorone with hydrogen cyanide in the presence of a base as a catalyst to obtain a crude isophoronenitrile product, and subsequently distilling the crude isophoronenitrile product, with the addition before distillation of at least one specific sulfonic acid or specific carboxylic acid. In addition, the present invention relates to the use of a specific sulfonic acid or of a specific carboxylic acid as a neutralizing agent before distillation of a crude isophoronenitrile product which has been obtained by reacting isophorone with hydrogen cyanide in the presence of a base as a catalyst, in order to avoid precipitates in the neutralization of the base used as a catalyst with an acid.