Method for cyclic hydrocarbon crystallization and separation

Claim 1

A CONTINUOUS PROCESS FOR RECOVERING A NORMALLY LIQUID CYCLIC HYDROCARBON COMPOUND CRYSTALLIZABLE AT A CRYSTALLIZATION TEMPERATURE NO LESS THAN -95*F. FROM A FEED STOCK CONSISTING OF A LIQUID MIXTURE OF ORGANIC HYDROCARBON COMPOUNDS INCLUDING SAID CYCLIC COMPOUND WHICH COMPRISES THE STEPS OF CONTINUOUSLY CHILLING A STREAM OF SAID FEED STOCK IN A CHILLING ZONE TO A CRYSTALLIZATION TEMPERATURE NO LESS THAN -95*F. TO PARTIALLY CRYSTALLIZE SAID CYCLIC COMPOUND TO PROVIDE A SLURRY OR 5 TO 20 VOLUME PERCENT OF CRYSTALS OF SAID CYCLIC COMPOUND IN A MOTHER LIQUOR CONTAINING SAID CYCLIC COMPOUND IN LIQUID FORM, CONTINUOUSLY INTRODUCING SAID SLURRY TO THE FIRST PHASE OF A TWO PHASE SLURRY HOLDING ZONE COMPRISING A FIRST PHASE OF GREATER CRYSTAL DENSITY HAVING A 25 TO 60 VOLUME PERCENT CONTENT OF CRYSTALS OF SAID CYCLIC COMPOUND AND A SECOND PHASE OF LESSER CRYSTAL DENSITY HAVING A TOTAL CONTENT OF CRYSTALLIZED AND LIQUID CYCLIC COMPOUND NO GREATER THAN THE INITIAL LIQUID CONTENT OF SAID CYCLIC COMPOUND IN SAID FEED STOCK, A PORTION OF THE CRYSTALS FROM THE FIRST PHASE PASSING TO THE SECOND PHASE, SAID SLURRY HOLDING ZONE BEING MAINTAINED AT SAID CRYSTALLIZATION TEMPERATURE AND SAID SECOND PHASE BEING MAINTAINED QUIESCENT, CONTINUOUSLY REMOVING MOTHER LIQUOR AND CRYSTALS OF SAID CYCLIC COMPOUND FROM THE FIRST PHASE AND FROM THE SECOND PHASE OF SAID SLURRY HOLDING ZONE, SEPARATING SAID REMOVED CRYSTALS AND SAID REMOVED MOTHER LIQUOR FROM THE FIRST PHASE INTO A FILTER CAKE FRACTION AND A FILTRATE FRACTION, SAID CRYSTALS AND MOTHER LIQUOR BEING WITHDRAWN FROM THE SECOND PHASE OF SAID SLURRY HOLDING ZONE AT A RATE EQUAL TO THE RATE OF CHARGE OF SAID SLURRY TO THE FIRST PHASE OF SAID SLURRY HOLDING ZONE, THE RATIO OF WITHDRAWN CRYSTALS TO WITHDRAWN MOTHER LIQUOR FROM THE SECOND PHASE BEING SUCH THAT SAID CYCLIC COMPOUND IS WITHDRAWN FROM SAID SLURRY HOLDING ZONE AT A RATE SUBSTANTIALLY EQUAL TO THE RATE OF CHARGE OF SAID SELECTED COMPOUND TO SAID SLURRY HOLDING ZONE.