Hydrodealkylation with azeotrope recycle

Claim 1

IN THE PROCESS OF DEALKLATING ALKYLATED AROMATIC HYDROCARBONS AT A CONVERSION RATE OF AT LEAST 60 PERCENT PER PASS TO PRODUCE BENZENE WHEREIN THE ALKYLATED AROMATIC HYDROCARBONS ARE CONTACTED IN A REACTION ZONE AT A TEMPERATURE BETWEEN 1100*F. AND 1500*F. AND AT A PRESSURE BETWEEN ABOUT 500 P.S.I.G. AND 800 P.S.I.G. WITH A HYDROGEN-RICH GAS, SAID CONTACTING BEING CARRIED OUT IN THE SUBSTANTIAL ABSENCE OF SOLIDS HAVING SURFACES WHICH WOULD TEND TO CATALYZE THE REACTION, THE REACTION QUENCHED WITH HYDROGEN TO MAINTAIN A TEMPERATURE DIFFERENCE IN THE REACTION ZONE BETWEEN MAXIMUM AND MINIMUM REACTION TEMPERATURES OF NOT TO EXCEED ABOUT 200*F., THE REACTION EFFLUENT FROM THE REACTION ZONE COOLED TO STOP THE REACTION, AND THE BENZENE IS SEPARATED FROM HYDROGEN IN A FLASH CHAMBER, FROM LIGHT HYDROCARBON GASES IN A FIRST FRACTIONATING ZONE AND FROM UNREACTED ALKYLATED AROMATIC HYDROCARBONS IN A SECOND FRACTIONATING ZONE, THE IMPROVEMENT WHICH COMPRISES REMOVING FROM SAID FIRST FRACTIONATING ZONE A SIDE-STREAM OF BENZENE TOGETHER WITH HYDROCARBON COMPOUNDS WHICH FORM AZEOTROPIC BOILING MIXTURES WITH THE BENZENE AND RETURNING THE MIXTURE OF BENZENE AND HYDROCARBON COMPOUNDS TO SAID REACTION ZONE.