Method for the purification of (meth)acrylic acid

US7557246B2 · kind B2 · utility

Assignee

• Evonik Stockhausen GmbH · US

Inventors

• Stefan Nordhoff · Recklinghausen, DE
• Torsten Balduf · Pfungstadt, DE
• Jurgen Mosler · Marl, DE
• Wilfried Uhlich · Marl, DE
• Dennis Thong Yu-Chiang · Marl, DE
• Axel Kobus · Langen, DE
• Arndt Selbach · Dirmstein, DE
• Jurgen Kohn · Rheinberg, DE

Key dates

• Filing date: Jul 15, 2005
• Grant date: Jul 7, 2009
• Expiry date: Jul 15, 2025

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C51/43
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

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.