Patent ID: 7083748
Filing Date: 2006-08-01
Classification: B01D,B01J

Abstract:
1. A method for continuously producing particles, comprising the steps of: flowing a supercritical fluid into an extraction chamber that is maintained at a temperature and a pressure sufficient to keep the supercritical fluid in a supercritical state; flowing an emulsion into the extraction chamber simultaneous with the flow of supercritical fluid, the emulsion having a discontinuous phase comprising a first solvent that is soluble in the supercritical fluid, and a continuous phase comprising a second solvent that is less soluble in the supercritical fluid than the first solvent, the discontinuous phase further comprising a solute dissolved in the first solvent, whereby upon contacting the supercritical fluid the first solvent dissolves from the emulsion into the supercritical fluid causing the solute to precipitate as particles that become suspended in the second solvent; flowing the first solvent-bearing supercritical fluid and the precipitated solute particles suspended in the second solvent out of the extraction chamber at the same rate as the emulsion and the supercritical fluid are flowing into the extraction chamber; and separating the suspension comprising the precipitated solute particles suspended in the second solvent from the first solvent-bearing supercritical fluid while maintaining the supercritical fluid in a supercritical state.