Patent ID: 7223883

Claim:
A process for reduction and/ or removal of permanganate-reducing compounds (PRC's) and C 2-12 alkyl iodide compounds formed in the carbonylation of a carbonylatable reactant selected from the group consisting of methanol, methyl acetate, methyl formate and dimethyl ether and mixtures thereof to produce a product comprising acetic acid, comprising the steps of: separating said carbonylation product to provide a volatile phase comprising acetic acid, and a less volatile phase; distilling said volatile phase to yield a purified acetic acid product and a first overhead comprising organic iodide, water, acetic acid, and at least one PRC; distilling at least a portion of the first overhead in a distillation apparatus to form a PRC enriched second overhead; extracting the second overhead with water and separating therefrom an aqueous stream comprising said at least one PRC; and recycling at least a first portion of the extracted second overhead to said distillation apparatus.