Acrylic Acid → Acrylic Acid

Participants

Reaction Steps

Apart from the above-described absorption of the reaction product comprising acrylic acid into a high boiling solvent mixture, other existing processes involve a total condensation of acrylic acid and of the water of reaction also formed in the course of the catalytic oxidation. The result is an aqueous acrylic acid solution which can be further worked up by distillation with an azeotropic agent (cf. DE-C 34 29 391, JA 11 24 766, JA 71 18 766, JA 71 18 966-R, JA 71 18968-R, JA-72 41 885) or by an extraction process (cf. DE-A 2 164 767, J5 81 40-039, J4 80 91 013). In EP-A 551 111, the mixture of acrylic acid and byproducts from the catalytic gas phase oxidation is contacted with water in an absorption tower and the resulting aqueous solution is distilled in the presence of a solvent which forms an azeotrope with polar low boilers such as water or acetic acid. DE-C 23 23 328 describes the removal of acrylic acid from an aqueous acrylic acid esterification waste liquor or an aqueous acrylic acid solution as formed in acrylic acid production by oxidation of propene or acrolein by extraction with a specific mixture of organic solvents.

Provenance & Evidence