Patent ID: 9156768
Filing Date: 2015-10-13
Classification: B01D,C07C,Y10S

Abstract:
1. A process for separating acrylic acid from a composition that comprises acrylic acid and an accompanying product, the process comprising: first, contacting the composition with an aqueous liquid stream, thereby obtaining a liquid solution comprising acrylic acid, accompanying product, and water, adding an entrainer to the liquid solution, thereby obtaining a heterogeneous minimum azeotrope with the water of the liquid solution, separating the liquid solution by distillation into an overhead product comprising the minimum azeotrope and a bottom product comprising acrylic acid and the accompanying product, separating the overhead product into water and a recirculatable entrainer, and separating the bottom product by distillation into acrylic acid and the accompanying product, wherein separating the bottom product comprises: introducing and separating the bottom product in a distillation column that comprises a side offtake, taking off high-boiling constituents of the accompanying product from a bottom of the distillation column, taking off low-boiling constituents of the accompanying product from a top of the distillation column, and taking off the acrylic acid from the side offtake, wherein taking off the acrylic acid from the side offtake comprises taking off the acrylic acid from the side offtake in a liquid form, wherein the distillation column is a dividing wall column comprising a dividing wall extending essentially vertically through the column, wherein the dividing wall extends from a dividing wall-free top region to a dividing wall-free bottom region or to a floor of a bottom, and wherein the distillation column further comprises a barrier wall that is constructed to close off a part of the distillation column located on a side of the side offtake from the dividing wall-free top region.