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. 27, 2014
Filed:
Jan. 26, 2010
Applicants:
Koji Ueno, Hyogo, JP;
Kunihiko Suzuki, Hyogo, JP;
Atsushi Sugano, Hyogo, JP;
Inventors:
Assignee:
Nippon Shokubai Co., Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B01D 41/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
[PROBLEM] There is provided a method for regenerating a filter, by which deterioration of the color tone of purified acrylic acid can be prevented. [SOLUTION] There is provided a method for regenerating a filter which has been used in a filtration step in the process for producing an acrylic acid, comprising a step (A) wherein the filter is washed with an aqueous alkaline solution, a step (B) wherein the filter is washed with water after the step (A) , and a step (C) wherein the filter is brought into contact with the acrylic acid for regeneration for at least one hour after the step (B).