Process for production of high octane hydrocarbons

Claim 1

A PROCESS FOR PRODUCING HIGH OCTANE GASOLINE BLENDING STOCKS FROM LOW OCTANE NAPHTHAS, WHICH PROCESS COMPRISES CONTACTING IN A REFORMING ZONE A NAPHTHA FEED ADMIXED WITH A HYDROGEN-RICH RECYCLE GAS WITH A PLATINUMALUMINA REFORMING CATALYST UNDER A COMBINATION OF REFORMING CONDITIONS, SAID CONDITIONS COMPRISING A TEMPERATURE IN THE RANGE OF BETWEEN OF BETWEEN ABOUT 150 TO 400 F., A PRESSURE IN THE RANGE OF BETWEEN ABOUT 150 TO 400 P.S.I.G., A RECYCLE GAS RATE IN THE RANGE OF ABOUT 2,000 TO 10,000 S.C.F. PER BARREL OF NAPHTHA AND A WEIGHT HOURLY BASIS VELOCITY IN THE RANGE OF ABOUT 0.5 TO 5, PRODUCING THEREBY A REFORMATE HAVING A C5+ OCTANE NUMBER OF AT LEAST ABOUT 95 CFR-R (CLEAR), SEPARATING THE EFFLUENT GAS AND A LIQUID REFORMATE, FRACTIONZATING SAID LIQUID REGAS AND A LIQUID REFORMATE, FRACTIONATING SAID LIQUID REFORMATE INTO A LIGHT FRACTION BOILING BELOW ABOUT 150*F., A MIDDLE FRACTION BOILING WITHIN THE RANGE OF ABOUT 150* F TO 280*F. AND A HEAVY FRACTION, SAID HEAVY FRACTION BOILING ABOVE SAID MIDDLE FRACTION AND IN THE RANGE OF BETWEEN AN INITIAL BOILING POINT OF ABOUT 220*F. TO 280*F. TO THE END POINT OF SAID REFORMATE, AND CONTAINING AT LEAST ABOUT 85 VOLUME PERCENT AROMATICS, CHARGING SAID MIDDLE FRACTION IN THE LIQUID PHASE TO A FIRST ADSORBER COMPRISING A BED OF SILICA GEL IN PARTICLE FORM, WITHDRAWING A DEAROMATIZED RAFFINATE FROM SAID ADSORBER CONTINUING TO CHARGE SAID MIDDLE FRACTION TO SAID FIRST ADSORBER UNTIL SAID SILICA GEL BECOMES SUBSTANTIALLY SATURATED WITH AROMATICS ADSORBED FROM SAID MIDDLE FRACTION, THEREAFTER CHARGING SAID MIDDLE FRACTION TO A SECOND ADSORBER COMPRISING A BED OF SILICA GEL IN PARTICLE FORM, DESORBING SAID FIRST ADSORBER BY A PROCESS WHICH COMPRISES PURGING LIQUID FROM SAID FIRST ADSORBER BY PASSING THEREUNTO AT LEAST A PORTION OF SAID RECYCLE GAS, PASSING THROUGH SAID FIRST ADSORBER AT LEAST A PORTION OF A SAID HEAVY FRACTION AT A TEMPERATURE IN THE RANGE OF ABOUT 140*F. TO 650*F. UNTIL DESORPTION OF AROMATICS PREVIOUSLY ADSORBED FROM SAID MIDDLE FRACTION IS SUBSTANTIALLY COMPLETED, AND AGAIN PURGING LIQUID FROM SAID FIRST ADSORBER BY PASSING THEREINTO AT LEAST A PORTION OF SAID RECYCLE GAS, THEREAFTER CHARGING SAID MIDDLE FRACTION TO THE DESORBED FIRST ADSORBER, DESORBING SAID SECOND ADSORBER, REPEATING THE ADSORPTION-DESORBING SAID SECOND ADTAINING A HIGH-OCTANE GASOLINE BLENDING STOCK BY BLENDING ANY REMAINDER OF SAID HEAVY FRACTION WITHS THE EFFLUENT REMOVED FROM SAID ADSORBERS WHILE PASSING THEREUNTO AT LEAST A PORTION OF SAID HEAVY FRACTION.