Bypassing eutectics with extractive crystallization: Design alternatives and tradeoffs



A systematic design method reported here uses extractive crystallization to separate a three-component mixture despite the presence of eutectics. Phase behavior can be classified into six basic types, and six flowsheet structures can handle systems with any of these solid-liquid-phase behaviors. Design equations are formulated for these flowsheet structures, and design variables and constraints are identified. In addition, design issues, such as the choice of solvent, the effect of design variables on recycle flows, and the magnitude of the costs, are discussed.