ACETIC ACID PRODUCTION METHOD Russian patent published in 2010 - IPC C07C51/44 C07C51/12 C07C51/48 C07C53/08 C07C51/10 C07C51/42 

FIELD: chemistry.

SUBSTANCE: method involves the following steps: (a) separation of a carbonylation product to obtain a gaseous overhead fraction containing acetic acid, methanol, methyl iodide, water, methyl acetate and at least one permanganate reducing compound, including acetaldehyde and less volatile fractions of catalyst; (b) distillation of the gaseous overhead fraction to obtain purified acetic acid and a low-boiling gaseous overhead fraction containing methanol, methyl iodide, water, acetic acid, methyl acetate and at least one permanganate reducing compound, including acetaldehyde; (c) condensation of the low-boiling gaseous overhead fraction and its separation into a condensed heavy liquid fraction which contains methyl iodide and methyl acetate and a condensed light liquid fraction containing water, acetic acid and at least one permanganate reducing compound, including acetaldehyde; (d) distillation of the light liquid fraction in a separate distillation column to obtain a second gaseous overhead fraction containing methyl iodide and at least one permanganate reducing compound, including acetaldehyde, and residue containing a fraction of high-boiling liquid containing methyl acetate, water and acetic acid, where the second gaseous overhead fraction is rich in permanganate reducing compounds relative the light liquid fraction; (e) condensation of the second gaseous overhead fraction containing methyl iodide and at least one permanganate reducing compound, including acetaldehyde, and aqueous extraction of the condensed stream to obtain a stream of an aqueous solution containing permanganate reducing compounds, including acetaldehyde, and a raffinate containing methyl iodide.

EFFECT: selective extraction and reduced amount of permanganate reducing compounds.

20 cl, 1 dwg