摘要 |
The gas reaction mixture ( 1 ), formed of propylene, if the case arises, of ultimate oxidation products, of acrylic acid, of acrolein, of steam, of acetic acid and of heavy products, is sent to the bottom of an absorption column (C 1 ) fed countercurrentwise at the top with a heavy hydrophobic absorption solvent. The gas flow ( 7 ), formed of propylene and of ultimate oxidation products, of major amounts of water and acetic acid, and of acrolein, is obtained at the top of (C 1 ) and a flow ( 4 ), formed of acrylic acid, of the heavy solvent, of heavy products and of minor amounts of acetic acid and of water, is obtained at the bottom of (C 1 ). The flow ( 7 ) is sent to a heat exchanger (C 3 ), where it is brought into contact with a descending liquid stream ( 8 ), fed at the top of (C 3 ), composed of the recycling of a portion of the flow ( 9 ), cooled beforehand, from the bottom of (C 3 ), in order to obtain, at the top, a gas flow ( 10 ) comprising the compounds present in the flow ( 7 ), except for most of the water and all the acetic acid, removed in the flow ( 9 ) from the bottom of (C 3 ). |