(Meth) acrylic acid is isolated by rectifying a mixture containing (meth) acrylic acid as a main component and a lower aldehyde as a secondary component in a rectification column composed of a stripping region and a rectification region

摘要

The present invention relates to a process for producing a starting material which is not directly fed to a rectification column but which is to be separated by rectification and which contains (meth) acrylic acid, is transferred into a heating type retention vessel connected to a middle stage side of a rectification region of a rectification column, (Meth) acrylic acid as a main component in a rectification column consisting of a stripping region and a rectification region, characterized in that the mixture is maintained at the boiling point and the bottom liquid of the retention vessel is fed into the rectification column instead of the starting mixture. And (meth) acrylic acid is isolated by rectifying a mixture containing a lower aldehyde as a secondary component.