Method for producing acrylic acid and methacrylic acid

US6448439B1 · kind B1 · utility

Assignee

• BASFAktiengesellschaft · DE

Inventors

• Bernd Eck · Viernheim, DE
• Otto Machhammer · Mannheim, DE
• Theo Proll · Bad Dürkheim, DE
• Volker Schliephake · Schifferstadt, DE
• Joachim Thiel · Neustadt, DE
• Klaus Bröllos · Seeheim-Jugenheim, DE

Key dates

• Filing date: Mar 13, 2000
• Grant date: Sep 10, 2002
• Expiry date: Mar 13, 2020

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 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. The product is removed from the gaseous product mixture by a process comprising the following steps:(a) condensing said gaseous product mixture,(b) crystallizing acrylic acid or methacrylic acid from the solution obtained in step (a),(c) removing the resulting crystals from the mother liquor, and(d) recycling at least a portion of said mother liquor from step (c) into step (a).