Process for separating iodine and its compounds from the carbonylation products obtained by subjecting dimethylether, methyl acetate or methanol to a carbonylation reaction

Abstract From the Canadian patent

The disclosure relates to a process for separating iodine and its compounds from the carbonylation products acetic acid acetic anhydride or ethylidene diacetate obtained by subjecting dimethylether, methyl acetate or methanol to a carbonylation reaction. For reducing the quantity of total iodine cantaminating the carbonylation products to less than 20 ppb iodine, the disclosure provides for the carbonylation products to be treated at temperatures of 20 to 250°C with an alkyl or aryl phosphine or a heterocyclic aromatic nitrogen compound and at least one of the metals copper, silver zinc or cadmium, or their compounds and to be distillatively separated from the iodine thereby fixed in …