Recovery of cyclo and methylcyclo

Claim 1

IN A PROCESS FOR SEPARATING AND RECOVERING CYCLOPENTAMIENE AND METHYL CYCLOPENTADIENE FROM THEIR DIMERS AND CODIMERS IN A CRACKED PETROLEUM CONCENTRATE BY VAPOR PHASE CRACKING OF THE DIMERS AND CODIMERS IN SAID CONCENTRATE, THE IMPROVEMENT WHICH COMPRISES PASSING SAID DIMERS AND CODIMERS IN THE VAPOR PHASE UP THROUGH THE CRACKING REACTION ZONE IN A FRACTIONATING COLUMN; SIMULTANEOUSLY PASSING CONTERCURRENT TO SAID VAPORS A THERMALLY STABLE ORGANIC OIL EHICH BOILS ABOVE AN INITIAL BOILING POINT OF 371* C. UNDER ATMOSPHERIC PRESSURE DOWN THROUGH SAID REACTION ZONE BY INTRODUCING SAID OIL AT AN UPPER PART IN SAID COLUMN, PRETREATING SAID THERMALLY STABLE OIL TO A TEMPERATURE IN THE RANGE OF 300* TO 500* C. BEFORE IT IS PASSED INTO THE UPPER PART OF THE FRACTIONATING COLUMN; TAKING OFF A LOW BOILING VAPOR FRACTION CONTAINING CYCLOPENTADIENE AND METHYL CYCLOPENTADIENE MONOMERS WITH THEIR DIMERS AND CODIMERS AT OVERHEAD VAPOR TEMPERATURES OF 200* TO 230* C. FROM AN UPPER PART OF THE FRACTIONATING COLUMN ABOVE THE POINT WHERE SAID THERMALLY STABLE LIQUID OIL IS INTRODUCED FOR FUTHER FRACTIONATION AND RECOVERY OF MONOMERS FROM THE OVERHEAD PRODUCT, AND WITHDRAWING THE THERMALLY STABLE LIQUID OIL FROM A BOTTOM PART OF THE FRACTIONATING COLUMN.