Separation of acrylic acid from liquid mixture, for use as monomer, by rectification in column in presence of diacrylic acid as polymerization inhibitor in upper part of column

摘要

In the separation of a liquid (F) containing acrylic acid (I) by supplying (F) to an inlet site (Z) of a rectification column and recovering a stream (S) having a (I) content of at least 90 wt. % (and higher than that of (F)) from an outlet site (E) above (Z), the content (G) of diacrylic acid (II) in the reflux liquid in the region of the column at least two theoretical plates above (Z) is at least 550 ppm by weight.