Combination process of hydrocracking and isomerization of hydrocarbons with the addition of olefins in the isomerization zone

Claim 1

A COMBINATION HYDROCRACKING AND ISOMERIZATION-HYDROGENATION REFINING PROCESS WHICH COMPRISES: (A) CONTACTING A HYDROCARBON FEED IN A HYDROCRACKING ZONE AT HYDROCRACKING CONDITIONS WITH A HYDROCRACKING CATALYST IN THE PRESENCE OF AN EXCESS OF HYDROGENAFFORDING GAS TO OBTAIN A HYDROGEN-CONTAINING LOWER BOILING EFFLUENT CONTAINING AROMATIC HYDROCARBONS; AND (B) CONVERTING A LIGHT OLEFIN HYDROCARBON FEED TO BRANCHED-CHAIN PARAFFINIC HYDROCARBON BY CONTACTING SAID OLEFIN HYDROCARBONS AT ISOMERIZATION-HYDROGENATION CONDITIONS WITH AN ACTIVE COMPOSITE ISOMERIZATION-HYDROGENATION CATALYST IN AN ISOMERIZATION-HYDROGENATION ZONE IN THE PRESENCE OF AT LEAST A PORTION OF SAID HYDROGEN-CONTAINING EFFLUENT FROM SAID HYDROCRACKING ZONE WHICH EFFLUENT PROVIDES A MINOR AMOUNT, BASED UPON OLEFIN FEED, OF A POLYCYCLIC AROMATIC HYDROCARBON EFFECTIVE TO REDUCE FORMATION OF SIDE REACTION PRODUCTS IN THE ISOMERIZATION-HYDROGENATION ZONE, SAID OLEFIN FEED INTRODUCED INTO SAID