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:
Mar. 13, 2007
Filed:
Jun. 10, 2004
Shuhei Yada, Mie, JP;
Kiyoshi Takahashi, Tokyo, JP;
Kenji Takasaki, Mie, JP;
Yasushi Ogawa, Mie, JP;
Kimikatsu Jinno, Mie, JP;
Yoshiro Suzuki, Mie, JP;
Shuhei Yada, Mie, JP;
Kiyoshi Takahashi, Tokyo, JP;
Kenji Takasaki, Mie, JP;
Yasushi Ogawa, Mie, JP;
Kimikatsu Jinno, Mie, JP;
Yoshiro Suzuki, Mie, JP;
Mitsubishi Chemical Corporation, Tokyo, JP;
Abstract
Clogging of a distillation column by polymerization caused by a change of the production rate of (meth)acrylic acid, is prevented to carry out a stabilized operation over a long period. A process for producing (meth)acrylic acid, which includes a purification step wherein a (meth)acrylic acid-containing material to be purified is supplied to and distilled by a distillation column, wherein during a cut operation in which the production rate of (meth)acrylic acid is reduced by α% relative to the production rate of (meth)acrylic acid during the ordinary operation, the liquid/gas flow rate in the distillation column is adjusted to be at least (100−α/2)% of the liquid/gas flow rate during the ordinary operation.