Production of para xylene

Claim 1

A CYCLIC PROCESS FOR RECOVERING PARAXYLENE FROM A HYDROCARBON LIQUID COMPRISING THE STEPS OF TIAL AMOUNTS OF ORTHOXYLENE, METAXYLENE AND PARAXYLENE, EACH CYCLE COMPRISING THE STEPS OF COOLING SAID LIQUID TO A TEMPERATURE IN THE RANGE -75* F. TO -120* F. FOR A TIME SUFFICIENT TO CAUSE THE FORMATION OF A SOLID CRYSTAL PHASE COMPRISING PARAXYLENE, FILTERING THE COOLED MIXTURE TO SEPARATE THE CRYSTALLINE PHASE AND A MOTHER LIQUOR AND WITHDRAWING THE MOTHER LIQUOR AS A PRODUCT, WASHING THE CRYSTAL PHASE WITH A WASH LIQUID HAVING A PARAXYLENE CONTENT SUBSTANTIALLY GREATER THAN THAT OF THE MOTHER LIQUOR, FILTERING THE WASH LIQUID FROM THE CRYSTAL PHASE, WITHDRAWING THE WASHED CRYSTAL PHASE AS A PRODUCT, CONDUCTING THE WASHING AND SECOND MENTIONED FILTERING STEPS AT TEMPERATURES SUBSTANTIALLY ABOVE THE TEMPERATURE OF THE COOLING ZONE SUCH THAT A SUBSTANTIAL PORTION OF THE CRYSTAL PHASE IS MELTED DURING SAID STEPS, RETURNING A PORTION OF THE FILTRATE FROM THE SECOND MENTIONED FILTERING STEP TO THE COOLING ZONE DURING THE SUCCEEDING CYCLE AND UTILIZING THE REMAINDER AS THE SPECIFIED WASH LIQUID TO WASH THE CRYSTAL PHASE PRODUCED IN THE SUCCEEDING CYCLE OF OPERATION.