PURIFICATION OF SOLVENT USED FOR EXTRACTIVE RECTIFICATION SEPARATION OF STYRENE AND STYRENE SEPARATION METHOD

摘要

A method for purifying a solvent used for extractive rectification separation of styrene, comprising: introducing a styrene-containing raw material from a center portion into an extractive rectification column; introducing an extractive rectification solvent from an upper portion into the extractive rectification column; following extractive rectification, discharging a raffinate oil from the top of the extractive rectification column, and discharging a styrene-rich rich solvent from the bottom of the extractive rectification column; introducing the rich solvent from the center portion into a solvent recovery column; following reduced pressure distillation, discharging the crude styrene from the top of the solvent recovery column; discharging a poor solvent from the bottom of the solvent recovery column and recycling the same to the upper portion of the extractive rectification column; diverting a portion of the rich solvent to a solvent purification region and introducing water into the solvent purification region; following liquid-liquid extraction, discharging a mixture of styrene polymer and styrene from the top of the solvent purification region; and discharging a purified water-containing solvent from the bottom of the solvent purification region. An application of the above method effectively removes the styrene polymer in the extractive rectification solvent, and simplifies the solvent purifying agent treatment step, thereby ensuring the extractive rectification capabilities of the solvent, and prolonging stable operating time of the device.