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. 05, 2021
Filed:
Sep. 06, 2018
Evonik Operations Gmbh, Essen, DE;
Manfred Kreczinski, Herne, DE;
Robert Jansen, Bottrop, DE;
Matthias Woyciechowski, Langenselbold, DE;
Evonik Operations GmbH, Essen, DE;
Abstract
Contaminated wastewater from the preparation of isophorone, isophoronenitrile and isophoronediamine is treated by A) 1. treating the wastewater from the preparation of isophoronenitrile from the reaction of isophorone with hydrogen cyanide by alkaline hydrolysis of isophoronenitrile to isophorone, and the salts of hydrogen cyanide within a pH range of 12.0 to 13.7 and at temperatures of 60 to 200° C. and 2. processing the wastewater from A) 1. by an oxidation, or B) treating the wastewater from the preparation of isophoronenitrile from the reaction of isophorone with hydrogen cyanide by an oxidation, or C) processing the wastewater from A) 1. and the wastewater from the preparation of isophorone and/or the wastewater from the preparation of isophoronediamine by an oxidation.