Continuous distillation process for producing, for example, hydroquinone-stabilised acrylic acid

摘要

Continuous distillation process by means of a rectification column for producing stabilised unsaturated carboxylic acids, for example hydroquinone-stabilised acrylic acid, in which a) crude acrylic acid, consisting of acrylic acid and high-boiling by-products, is fed to the rectification column, b) acrylic acid is drawn off as the top product, c) a mixture of high-boiling by-products/acrylic acid is drawn off as the bottom product, d) a stabiliser, for example hydroquinone, is added to the distillate and to the reflux, and e) a temperature-resistant, highly active inhibitor is added to the rectification column a few plates below the reflux supply. <IMAGE>