Process for isolating methacrylic acid by extraction.

摘要

Methacrylic acid is isolated by solvent extraction from an aqueous methacrylic acid solution obtained from a gas phase catalytic oxidation reaction. To avoid interference of byproduct with the extraction, the aqueous methacrylic acid solution is previously first contacted with an extraction solvent, polymers precipitated out from the aqueous methacrylic acid solution are removed and the remainder is fed into the extraction column. Preferably the solvent of the first contact is the same as the solvent of the solvent extraction.