| abstract |
A process is described for separating acrylic acid from the reaction gases of the catalytic gas phase oxidation of propane, propylene and / or acrolein, in which the reaction gases are absorbed in a high-boiling liquid and the high-boiling liquid laden with acrylic acid is stripped off with a stripping gas to remove volatile impurities the high-boiling liquid laden with acrylic acid, crude acrylic acid is distilled off, the crude acrylic acid is treated with an aldehyde scavenger, and the treated crude acrylic acid is thermally separated into acrylic acid-containing vapors and a high-boiling residue in an arrangement of a distillation column and a downstream film evaporator, and the vapors are condensed to obtain pure acrylic acid. Very pure acrylic acid is obtained without the need for multi-stage distillations or crystallizations, which is directly suitable for the production of absorber resins. |