METHOD OF PREPARING ACRYLIC ACID AND METHACRYLIC ACID

摘要

A method of preparing acrylic acid or methacrylic acid comprises the following steps: (a) preparation of a gaseous reaction mixture which contains acrylic acid or methacrylic acid, essentially having the composition of a reaction mixture of catalytic gas-phase oxidation of C3/C4 alkanes, alkenes, alkanols and/or alkanals and/or precursors thereof to form acrylic acid or methacrylic acid, (b) absorption of the reaction product with a solvent mixture consisting of at least one lactame dissolved in at least one polar organic solvent, and (c) distillation of the reaction product-bearing solvent mixture to obtain a crude acrylic acid or crude methacrylic acid and the solvent mixture.