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:
Jul. 07, 2009
Filed:
Jul. 15, 2005
Stefan Nordhoff, Recklinghausen, DE;
Torsten Balduf, Houston, TX (US);
Jürgen Mosler, Castrop-Rauxel, DE;
Wilfried Uhlich, Marl, DE;
Dennis Thong Yu-chiang, Marl, DE;
Axel Kobus, Langen, DE;
Arndt Selbach, Marl, DE;
Jürgen Kohn, Rheinberg, DE;
Stefan Nordhoff, Recklinghausen, DE;
Torsten Balduf, Houston, TX (US);
Jürgen Mosler, Castrop-Rauxel, DE;
Wilfried Uhlich, Marl, DE;
Dennis Thong Yu-Chiang, Marl, DE;
Axel Kobus, Langen, DE;
Arndt Selbach, Marl, DE;
Jürgen Kohn, Rheinberg, DE;
Evonik Stockhausen GmbH, Krefeld, DE;
Abstract
The present invention relates to a process for production of (meth)acrylic acid, whereby first a crude (meth)acrylic acid is produced and this crude (meth)acrylic acid is then continuously purified, whereby the continuous purification of the crude (meth)acrylic acid comprises the following process steps: a) in a composition comprising (meth)acrylic acid and impurities, precipitating the impurities in crystalline form from the composition; and b) separating the crystalline impurities precipitated from the composition. The invention also relates to the (meth)acrylic acid obtainable by this process, a device for production of (meth)acrylic acid, the use of the device or of a purification device for production of (meth)acrylic acid, (meth)acrylic acid, water-absorbing polymers, the use of water-absorbing polymers as well as fibers, sheets, foams and composites.