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:
Dec. 23, 2025
Filed:
Jun. 17, 2021
Applicant:
Andritz Oy, Helsinki, FI;
Inventor:
Johan Olsson, Svedala, SE;
Assignee:
ANDRITZ OY, Helsinki, FI;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C 29/80 (2006.01); C07C 29/94 (2006.01); D21C 11/00 (2006.01);
U.S. Cl.
CPC ...
C07C 29/80 (2013.01); C07C 29/94 (2013.01); D21C 11/0007 (2013.01);
Abstract
A method of purifying raw methanol obtained in chemical pulping, wherein heavy oil is admixed with the raw methanol to prevent precipitation, and the methanol mixture is distilled or evaporated to recover the methanol. The heavy oil is formed by mixing and heating raw methanol obtained from a side stream of chemical hardwood pulping with an acidic aqueous solution to vaporize low boiling point sulfurous compounds and provide acidified raw methanol. The acidified raw methanol is separated into a liquid top phase, a liquid aqueous middle phase, and a liquid bottom phase. The liquid bottom phase is extracted to obtain the heavy oil.