Process for rectificative separation of (meth)acrylic acid from the (meth)acrylic acid and lower aldehydes containing mixture

摘要

In the sepn. of (meth)acrylic acid (I) from mixts. contg. (I) as main prod. and lower aldehydes as by-prods. by rectification in a column with a distn. zone and a concn. zone, the mixt. is not supplied to the column directly. Instead, it is passed to a heated dwell vessel connected to the concn. zone, in which the mixt. is kept boiling, and the sump liquid from this vessel is fed to the column.