Basf Aktiengesellschaft

Badische Anilin- & Soda-Fabrik Aktiengesellschaft

Walter Frey

Richard Krabetz

Heinz Engelbach

Gerd Duembgen

Fritz Thiessen

Carl-Heinz Willersinn

Ulrich Lebert

Hermann Spitzl

In the oxidation of propylene and/or acrolein, high-boiling or non-volatile byproducts are separated from the solvents used for absorbing the acrylic acid by treating the said solvents laden with byproducts with the hot reaction gases in such amounts that the major portion of the solvents evaporates, the residual solvent containing a high percentage of said byproducts then being discarded or worked up.

Method of separating high-boiling or non-volatile materials

In the oxidation of .alpha.-olefins in the gas phase to .alpha.,.beta.-olefinically unsaturated aldehydes and carboxylic acids with molecular oxygen in the presence of an inert gas using a catalyst containing molybdenum and bismuth with elements as oxides or mixed oxides at from 280.degree. to 450.degree. C a content of indium and/or aluminum and/or lanthanum and/or gallium as oxide or mixed oxide results in an improvement in the conversion and/or activity and/or life of the catalyst.

Catalytic oxidation of .alpha.-olefins

Acrylic acid practically devoid of water, acrolein, formaldehyde and acetic acid is obtained at particularly low cost by countercurrent scrubbing and quenching of the reaction gas formed in the catalytic oxidation of propylene and/or acrolein with a high-boiling, extremely hydrophobic solvent followed by processing of the extract.

Recovering anhydrous acrylic acid

Growing community of inventors

Mannheim, Germany

Walter Frey