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:
Apr. 23, 2013
Filed:
Apr. 24, 2009
Kazuhiko Sakamoto, Himeji, JP;
Masaru Ishikawa, Himeji, JP;
Kazuhiko Sakamoto, Himeji, JP;
Masaru Ishikawa, Himeji, JP;
Nippon Shokubai Co., Ltd., Osakak, JP;
Abstract
[Problem] There is provided, in a process for producing acrylic acid having a catalytic gas-phase oxidation reaction step, a condensation step, a collection step, a distillation step, a crystallization step, an acrylic acid recovering step or the like, a production method for acrylic acid, in which contamination of acrylic acid with protoanemonin without providing any additional purification treatment to the resultant purified acrylic acid can be reduced. [Solution] The problems described above can be solved by providing the production method for acrylic acid comprising A) a step obtaining an acrylic acid-containing gas by a catalytic gas-phase oxidation reaction of gas containing a acrylic acid raw material; B) a step of obtaining the acrylic acid-containing solution by introducing the acrylic acid-containing gas to the collection column or the condensation column and performing collection or condensation; C) a step of obtaining the crude acrylic acid by introducing the acrylic acid-containing solution to the distillation column or the crystallizer and performing distillation or crystallization, wherein a step of heat treating the acrylic acid-containing solution or the crude acrylic acid containing 100 ppm by mass or more of protoanemonin, under the condition of 100° C. or more of temperature, 1 hour or more of time and a step of introducing the heat-treated acrylic acid-containing solution or the crude acrylic acid to the collection column, the condensation column, the distillation column or the crystallizer, are included.