Patent ID: 6143927
Filing Date: 2000-11-07
Classification: B01D,B01J,C07C,Y02P

Abstract:
A method of removing a catalyst from a mixture comprising the catalyst, water, and at least one of hydrocarbon and solvent, the mixture having been formed after reaction of the hydrocarbon, in the solvent, with an oxidant to form an intermediate oxidation product at an operation temperature, in the presence of the catalyst, and water at a first water level, the method comprising the steps of:(a) changing the operation temperature to a temperature below a precipitation temperature at which and over which the catalyst in the mixture would precipitate, at least partially, if the water level in the mixture is reduced to or under a precipitation water level;(b) removing an adequate amount of water from the mixture to bring the water level to or under the precipitation water level, without causing the catalyst to precipitate;(c) changing the temperature of step (a) to a temperature at or above the precipitation temperature, thereby causing the catalyst to precipitate, at least partially; and(d) removing the precipitated catalyst from the mixture.