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:
Feb. 06, 1990
Filed:
Dec. 27, 1988
Hubert Coenen, Essen, DE;
Reinhard Konrad, Bochum, DE;
Fried. Krupp GmbH, , DE;
Abstract
A process for the extraction of vanillin by means of the extraction from a vanillin-containing, water-containing, liquid mixture of substances with carbon dioxide at a temperature of 0.degree. to 110.degree. C. as well as a pressure of 30 to 400 bar and a subsequent separation of vanillin is described. It is contemplated that with this process the vanillin-containing carbon dioxide is passed through an aqueous hydrogen sulfite- or sulfite-solution at the extraction temperature and the extraction pressure, that this solution is subsequently acidified with sulfuric acid to a pH value of 2 to 4, and that the vanillin-free carbon dioxide is fed back into the extraction stage.