Process for producing xylenes

Claim 1

A METHOD OF PRODUCING XYLENE ISOMERS FROM AROMATIC-RICH HYDROCARBON DISTILLATES, WHICH COMPRISES SELECTING AS A FEED STOCK A PETROLEUM HYDROCARBON FRACTION BOILING WITHIN A RANGE OF FROM 325 TO 450*F., AND HAVING AN AROMATIC CONTENT OF AT LEAST 75% BY VOLUME AND A BASIC NITROGEN CONTENT OF LESS THAN 10 P.P.M., CONTACTING SAID FEED STOCK IN ADMIXTURE WITH AT LEAST 200 S.C.F. HYDROGEN PER BARREL OF FEED IN AN ISOCRACKING ZONE WITH A CATALYST COMPRISING A HYDROGENATING COMPONENT SELECTED FROM THE GROUP CONSISTING OF NICKEL SULFIDE AND COBALT SULFIDE, DISPOSED ON AN ACTIVE ACID CRACKING SUPPORT AND HAVING A SEVERITY FACTOR IN THE RANGE OF ABOUT 0.1 TO 2.0, SAID ISOCRACKING ZONE BEING OPERATED AT PRESSURES OF AT LEAST ABOUT 400 P.S.I.G. AND AT INSTANTANEOUS CATALYST TEMPERATURES IN THE RANGE OF ABOUT 450* TO 730*F., WHEREBY THERE IS PRODUCED, IN A CONVERSION OF AT LEAST 20% PER PASS THROUGH THE ISOCRACKING ZONE, A SYNTHETIC PRODUCT BOILING ESSENTIALLY BELOW THE INITIAL BOILING POINT OF THE FEED, SAID SYNTHETIC PRODUCT BEING CHARACTERIZED BY THE FACT THAT OF THE AROMATIC PRESENT THEREIN BOILING BELOW ABOUT 325*F., AT LEAST 50% BY VOLUME CONSISTS OF XYLENE ISOMERS, THERE BEING CONSUMED IN SAID ISOCRACKING PROCESS AT LEAST 1000 S.C.F. OF HYDROGEN PER BARREL OF FEED CONVERTED TO SAID SYNTHETIC PRODUCT.

Claim 2

A METHOD OF PRODUCING XYLENE ISOMERS FROM AROMATIC-RICH HYDROCARBON DISTILLATES, WHICH COMPRISES SELECTING AS A FEED STOCK A PETROLEUM HYDROCARBON FRACTION BOILING WITHIN A RANGE OF FROM 325 TO 450*F., AND HAVING AN AROMATIC CONTENT OF AT LEAST 75% BY VOLUME AND A BASIC NITROGEN CONTENT OF LESS THAN 10 P.P.M., CONTACTING SAID FEED STOCK IN ADMIXTURE WITH AT LEAST 200 S.C.F. HYDROGEN PER BARREL OF FEED IN AN ISOCRACKING ZONE WITH A CATALYST COMPRISING A HYDROGENATING COMPONENT SELECTED FROM THE GROUP CONSISTING OF NICKEL SULFIDE AND COBALT SULFIDE, DISPOSED ON AN ACTIVE ACID CRACKING SUPPORT AND HAVING A SEVERITY FACTOR IN THE RANGE OF ABOUT 0.1 TO 2.0, SAID ISOCRACKING ZONE BEING OPERATED AT PRESSURES OF AT LEAST ABOUT 400 P.S.I.G. AND AT INSTANTANEOUS CATALYST TEMPERATURES IN THE RANGE OF ABOUT 450* TO 730*F., WHEREBY THERE IS PRODUCED, IN A CONVERSION OF AT LEAST 20% PER PASS THROUGH THE ISOCRACKING ZONE, A SYNTHETIC PRODUCT BOILING ESSENTIALLY BELOW THE INITIAL BOILING POINT OF THE FEED, SAID SYNTHETIC PRODUCT BEING CHARACTERIZED BY THE FACT THAT OF THE AROMATIC PRESENT THEREIN BOILING BELOW ABOUT 325*F., AT LEAST 50% BY VOLUME CONSISTS OF XYLENE ISOMERS, THERE BEING CONSUMED IN SAID ISOCRACKING PROCESS AT LEAST 1000 S.C.F. OF HYDROGEN PER BARREL OF FEED CONVERTED TO SAID SYNTHETIC PRODUCT.