Method for purifying acrylic acid and methacrylic acid

US6596901B1 · kind B1 · utility

Assignee

• BASF SE

Inventors

• Bernd Eck · Viernheim, DE
• Otto Machhammer · Mannheim, DE
• Theo Proll · Bad Dürkheim, DE
• Volker Schliephake · Schifferstadt, DE
• Klaus Joachim Müller-Engel · Blankenloch, DE

Key dates

• Filing date: Jan 8, 1999
• Grant date: Jul 22, 2003
• Expiry date: Jan 8, 2019

Classification

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

Abstract

A process for preparing acrylic acid or methacrylic acid comprises(a) preparing a gaseous product mixture having essentially the composition of a reaction mixture of the catalytic gas phase oxidation of C3-/C4-alkanes, -alkenes, -alkanols and/or -alkanals and/or precursors thereof to form acrylic acid or methacrylic acid, characterized by(b) condensing said product mixture,(c) crystallizing acrylic acid or methacrylic acid from the solution obtained in step (b), and(d) removing the resulting crystals from the mother liquor.