Isomerization of saturated hydrocarbons in the presence of a polynuclear condensed ring compound as cracking inhibitor

Claim 1

IN A ISOMERIZATION PROCESS IN WHICH A SATURATED HYDROCARBON IS ISOMERIZED IN THE PRESENCE OF HYDROGEN WITHOUT ANY APPRICABLE CONSUMPTION OF THE HYDROGEN BY CONTACT WITH A HYDROGENATION CATALYST SELECTED FROM THE GROUP CONSISTING OF VANADIUM OXIDE, MOLYBDENUM SULFIDE, MOLYBDENUM OXIDE, TUNGSTEN SULFIDE, IRON, COBALT, NICKEL, NICKEL OXIDE, IRON SULFIDE, NICKEL TUNGSTATE, AND COBALT MOLYBDATE AT AN ISOMERIZATION TEMPERATURE OF ABOUT 775* TO 1000* F. AND A PRESSURE IN EXCESS OF ABOUT 50 ROUNDS PER SQUARE INCH, THE IMPROVEMENT WHICH COMPRISES INHIBITING THE CRACKING OF SAID SATURATED HYDROCARBON BY ADDING TO IT A MINOR AMOUNT OF A POLYNUCLEAR CONDENSED RING COMPOUND SELECTED FROM THE GROUP CONSISTING OF THE TRINUCLEAR CARBOXYXLIC AROMATIC COMPOUNDS, THE BINUCLEAR HETEROCYCLIC NITROGEN AROMATIC COMPOUNDS, THE TRINUCLEAR HETEROCYCLIC NITROGEN AROMATIC COMPOUNDS, AND THIER HYDROGENATED DERIVATIVES, THE AMOUNT OF SAID ADDED POYLNUCLEAR CONDENSED RING COMPOUND BEING NOT MORE THAN 5 PER CENT BY WEIGHT OF THE SATURATED HYDROCARBON.