Methods for removing catalyst after oxidation of hydrocarbons
AssigneeRPC Inc.
InventorsMark W. Dassel, Ader M. Rostami, David C. DeCoster, Eustathios Vassiliou
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Abstract
This invention relates to methods for controlling the oxidation of hydrocarbons to intermediate oxidation products, such as adipic acid for example, by removing the catalyst from the reaction mixture, outside the reaction zone, after the oxidation has taken place at least partially. The catalyst is at least partially precipitated by reducing the water level in the reaction mixture and subjecting the reaction mixture to a temperature, at which or over which catalyst precipitates.
Claims32
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.
Dependencies are inferred from the claim text.