Patent ID: 6417128
Filing Date: 2002-07-09
Classification: C07C

Abstract:
A method of replacing water and cyclohexanone with acetic acid in an aqueous solution of a metal catalyst, the solution having been produced after oxidation of cyclohexane to adipic acid, the method comprising steps of:(a) feeding the aqueous solution of the metal catalyst to a top plate or an intermediate plate of a solvent exchange column, the solvent exchange column also having a bottom plate; (b) removing a bottoms liquid from the vicinity of the bottom plate, the bottoms liquid being at a bottoms temperature; (c) boiling the bottoms liquid in a re-boiler and returning produced bottoms vapors to the column in the vicinity of the bottom plate; (d) introducing acetic acid to the re-boiler or to the vicinity of the bottom plate; and (e) removing from the re-boiler an acetic acid solution of the metal catalyst comprising no substantial amounts of water and cyclohexanone.