ISOLATION OF (METH)ACRYLIC ACID FROM A MIXTURE CONTAINING (METH)ACRYLIC ACID AS THE MAIN COMPONENT AND LOWER ALDEHYDES AS SECONDARY COMPONENTS BY RECTIFICATION IN A RECTIFICATION COLUMN CONSISTING OF A STRIPPING SECTION AND A RECTIFICATI N SECTION

摘要

A process for the isolation of (meth)acrylic acid from a mixture containing (meth)acrylic acid as the main component and lower aldehydes as secondary components by rectification in a rectification column consisting of a stripping section and a rectification section, wherein the starting mixture comprising the (meth)acrylic acid to be isolated by rectification is not fed directly to the rectification column but is first passed into a heated dwell vessel which is connected to the vapor side of the rectification section of the rectification column and in which the starting mixture is kept at the boil and, instead of the starting mixture as such, the bottom liquid of the dwell vessel is fed to the rectification column.