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:
Jul. 11, 1989
Filed:
Oct. 08, 1987
Applicant:
Inventors:
Aarno Klemola, Valkeakoski, FI;
Juhani Tuovinen, Valkeakoski, FI;
Assignee:
Yhtyneet Paperitehtaat Oy, Valkeakoski, FI;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
568438 ; 568426 ;
Abstract
The invention relates to a method for the production of vanillin in the form of a very pure product by oxidizing lignin contained in the wood pulping liquor. According to the invention the separation and purification of vanillin from the reaction mixture is carried out by means of an extraction at a supercritical pressure and temperature. Carbon dioxide, for instance, can be used as a extraction gas.