PROCESS FOR THE SEPARATION OF IODINE AND ITS COMPOUNDS FROM CARBONYLATION PRODUCTS OBTAINED IN THE CARBONYLATION OF DIMETHYL ETHER, METHYL ACETATE AND METHANOL

摘要

The disclosure relates to a process for separating iodine and its compounds from the carbonlyation 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 contaminating the carbonlyation products to less than 20 ppb iodine, the disclosure provides for the carbonylation products to be treated at temperatures of 20 DEG to 250 DEG 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 non-volatile form.