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:
May. 19, 1981
Filed:
Dec. 28, 1976
Tetsuya Ogawa, Futsushi, JP;
Norio Yoshizaki, Ichiharashi, JP;
Tadakatsu Katsuragi, Ichiharashi, JP;
Makoto Nakamura, Ichiharashi, JP;
Kiyonori Shiiba, Ichiharashi, JP;
Chisso Corporation, Osaka, JP;
Abstract
A method for purifying raw acetic acid containing formaldehyde is provided wherein raw acetic acid is heat-treated at a temperature of about its boiling point or higher, in advance of the conventional distillation for removing a lower boiling fraction, and the acetic acid thus heat-treated is distilled to remove the lower boiling fraction, whereby the content of formaldehyde can be reduced down to 30 ppm or lower.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile