CRYSTALLISATION PROCESS FOR PRODUCING VERY PURE PARA-XYLENE

摘要

The invention is a novel energy efficient process to produce high purity paraxylene from a feed comprising at least 55 to 60 wt % paraxylene, wherein a first portion of high purity paraxylene product is obtained in a first crystallization step at about 10° F. to about 55° F. without the need for further reslurry and recrystallization, and wherein another portion of the high purity paraxylene product is obtained following a reslurry step which warms crystalline paraxylene obtained from subsequent lower temperature crystallizations to yield a slurry at a temperature of about 10° F. to about 55° F. without the need for further refrigeration.