Process for the preparation of acetic acid

Abstract

By employing a process for the preparation of acetic acid which comprises carbonylating methanol with carbon monoxide in a first reactor in the presence of a reaction fluid comprising a rhodium catalyst, methyl iodide, an iodide salt, methyl acetate and water, while continuously withdrawing the reaction fluid from the first reactor and introducing it into a flash zone to separate it into an evaporated part and an unevaporated part, characterized in that second reactor is provided between the first reactor and the flash zone and methanol is carbonylated with the carbon monoxide contained in the reaction fluid in a state in which it is dissolved therein in the second reactor with a residence time of 7 to 60 seconds at 150.degree. to 220.degree. C., the carbon monoxide contained in the reaction fluid withdrawn from the first reactor in a state in which it is dissolved therein can be converted into acetic acid in the second reactor through the same carbonylation as that occurring in the first reactor, which enables effective use and high recovery of carbon monoxide.

Dependencies are inferred from the claim text.