GB731549A - Production of acetic acid - Google Patents

Abstract

In the synthesis of acetic acid from carbon monoxide and methanol in the vapour phase in presence of active carbon impregnated with nickel iodide, the carbon monoxide is passed through successive zones of active carbon, the iodine content of the catalyst is maintained by a suitable supply to the reactor, the direction of flow of the reactants is periodically reversed, the methanol supply by-passes the first active carbon zone in the direction of flow obtaining, and the last such zone is maintained at a temperature above that at which acetic acid condenses but below reaction temperature so that it absorbs nickel from the outgoing vapours without condensation of acetic acid, and upon reversal of flow, yields nickel to the incoming gas. Iodine may be supplied as methyl iodide, and water or methyl acetate may be introduced to the reactor. The active carbon zones may be separated by mixing zones containing inert packing material, through which the methanol may be introduced. Liquid methanol supply or cooled recycled reaction mixture may be used for cooling. Where there are a number of mixing zones, methanol may be at first supplied only to the earlier ones in the direction of flow, then supplied to progressively later ones, until the last, when the direction of flow of the carbon monoxide is reversed. An example is given. Specification 692,145 is referred to.