A method for removal of permanganate reducing compound in carbonylation process for manufacturing acetic acid

Abstract

An improvement of the methanol carbonylation process for manufacturing acetic acid is disclosed. Specifically disclosed is a method for reducing the formation of alkyl iodides and C3-8 carboxylic acids by removing permanganate reducing compound ("PRC's") from the light phase of the condensed light ends overhead stream, including (a) distilling the light phase to yield a PRC enriched overhead stream; and (b) extracting the third overhead stream with water in at least two consecutive stages and separating therefrom one or more aqueous streams containing PRC"s.