BigPatents India

The inventive method for purifying (meth)acrylic acid by oxidising a propane and/or propylene and/or acrolein (acrylic acid production) and isobutane and/or isobutene and/or tert-butyl alcohol and/or methacroleine (methacrylic acid production) gaseous substrate consists in sending a gaseous mixture of a reaction (1) to the base of an absorption column (C1) which is supplied by the top and in counter-current by at least one type of hydrophobe absorption heavy solvent, in sending a flow (2) from the base of the column (C1) to a light component separation column (C2) and in sending a flow (4) from the base of the column (C2) to a separation device which is provided with three sections i.e. exhaustion (S1), concentration (S2) and rectification (S3), respectively in order to extract a pure desired acid, extract and advantageously recycling one or several types of heavy solvent in the absorption column (C1) and to separate intermediate heavy stabiliser-containing components from the desired (meth)acrylic acid.