Patent ID: 6248797
Filing Date: 2001-06-19
Classification: B01J,C08F,Y02P

Abstract:
A method for extracting a leachable contaminant from an ion exchange resin, comprising:(a) contacting the resin with supercritical carbon dioxide in an extraction vessel for a sufficient interval of time to allow at least a portion of said leachable contaminant to be solubilized by said supercritical carbon dioxide; and(b) removing from the resin the supercritical carbon dioxide having said leachable contaminant dissolved therein;wherein said step (a) includes a first period of time in which the solvent power of the supercritical fluid is increased by increasing supercritical carbon dioxide pressure in the extraction vessel, and a second period of time during which the resin is contacted with said supercritical carbon dioxide under dynamic conditions in which a flow of said supercritical carbon dioxide is maintained into and out of said extraction vessel.