Continuous process for the preparation of acetic anhydride or mixtures of acetic anhydride and acetic acid

摘要

Disclosed is a continuous process for the preparation of acetic anhydride which comprises carbonylating a mixture comprising (i) methyl iodide and (ii) methyl acetate and/or dimethyl ether in the presence of a rhodium catalyst and a promoter wherein the concentration of mesityl oxide in the carbonylation mixture is suppressed by the presence therein of at least 100 ppm of dissolved ferrous and/or cobaltous ion.