In a process for the synthesis of acetic acid from methanol and carbon monoxide in the presence of a nickel and iodine containing catalyst, the catalyst residue is recovered from the cinder product by stripping it with a gas containing at least 50% by volume of carbon monoxide and distilling under reduced pressure. The stripping gas which may be entirely carbon monoxide or also contain methane, carbon dioxide, nitrogen and hydrogen removes the nickel carbonyl and methyl iodide, and the crude product is then distilled under reduced pressure to leave non-volatile catalyst components e.g. nickel iodide or acetate as tails which may be recycled. The volatile catalysts may be washed from the stripping gas with methanol and the washed gases reused for the stripping. The stripping stages may be at atmospheric or higher pressures and the product comprising acetic acid, methyl acetate and alcohol, water, nickel iodide and acetate is distilled in two columns in series, in the first of which methyl acetate is distilled as heads between 55 and 60 DEG C., and in the second acetic acid and water are obtained in the head, and a solution or suspension of nickel acetate and iodide in acetic acid is discharged. The distilled acid may also be treated with activated carbon.
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