Catalytic cracking

Claim 1

A PROCESS FOR PRODUCING VALUABLE HYDROCARBON PRODUCTS WHICH COMPRISES CONTACTING IN A FIRST REACTION ZONE, A PETROLEUM FRACTION HAVING AN INITIAL BOILING POINT OF AT LEAST ABOUT 400*F., A 50 PERCENT POINT OF AT LEAST ABOUT 500*F. AND AN END BOILING POINT OF AT LEAST ABOUT 600* F. AND BOILING SUBSTANTIALLY CONTINUOUSLY BETWEEN SAID INITIAL BOILING POING AND SAID END BOILING POINT, WITH A CATALYST COMPRISING BETWEEN ABOUT 0.05 PERCENT AND ABOUT 20 PERCENT, BY WEIGHT OF THE CATALYST, OF AT LEAST ONE METAL SELECTED FROM THE GROUP CONSISTING OF METALS HAVING ATOMIC NUMBERS OF 44 TO 46, INCLUSIVE, AND 76 TO 78, INCLUSIVE, DEPOSITED UPON A SYNTHETIC COMPOSITE OF AT LEAST TWO SOLID REFRACTORY OXIDES OF ELEMENTS OF GROUPS IIA, IIIB AND IV OF THE PERIODIC ARRANGEMENT OF THE ELEMENTS, SAID COMPOSITE HAVING AN ACTIVITY INDEX OF AT LEAST 25, IN THE PRESENCE OF HYDROGEN IN AMOUNTS, EXPRESSED IN MOLAR RATIO OF HYDROGEN TO HYDROCARBON CHARGE, WITHIN THE RANGE ABOUT 2 TO ABOUT 80, AT A PRESSURE WITHIN THE RANGE ABOUT 100 POUNDS PER SQUARE INCH GAUGE TO ABOUT 2500 POUNDS PER SQUARE INCH GAUGE, AT A LIQUID HOURLY SPACE VELOCITY WITHIN THE RANGE ABOUT 0.1 TO ABOUT 10, AND AT A TEMPERATURE WITHIN THE RANGE ABOUT 0.1 TO ABOUT TO ABOUT 825*F., TO EFFECT CONVERSION INTO PRODUCTS BOILING AT TEMPERATURES LOWER THAN ABOUT 390*F. WITHIN THE RANGE ABOUT 5 VOLUME PERCENT AND ABOUT 50 VOLUME PERCENT AND TO PRODUCE AN EFFLUENT MATERIAL COMPRISING PRODUCTS BOILING AT TEMPERATURES LOWER THAN ABOUT 390*F., A PRODUCT BOILING AT TEMPERATURES HIGHER THAN ABOUT 390* F. AND A GASEOUS FRACTION RICH IN HYDROGEN, SEPARATING SAID PRODUCT BOILING AT TEMPERATURES HIGHER THAN ABOUT 390*F. INTO A LOWER BOILING FRACTION AND A HIGHER BOILING FRACTION, SAID LOWER BOILING FRACTION HAVING A BOILING RANGE WITHIN THE RANGE ABOUT 390*F TO ABOUT 450*-750*F. AND SAID HIGHER BOILING FRACTION HAVING A BOILING RANGE WITHIN THE RANGE ABOUT 450*-750*F. TO THE END BOILING POINT OF SAID PRODUCT BOILING AT TEMPERATURES HIGHER THAN ABOUT 390*F., CONTACTING EACH OF SAID FRACTIONS IN A SEPARATE REACTION ZONE WITH A CATALYST OF THE TYPE USED IN SAID FIRST REACTION ZONE, IN THE PRESENCE OF HYDROGEN IN AMOUNTS, EXPRESSED IN MOLAR RATIO OF HYDROGEN TO HYDROCARBON CHARGE, WITHIN THE RANGE ABOUT 2 TO ABOUT 80, AT A PRESSURE WITHIN THE RANGE ABOUT 100 POUNDS PER SQUARE INCH GAUGE TO ABOUT 2500 POUNDS PER SQUARE INCH GAUGE, AT A LIQUID HOURLY SPACE VELOCITY WITHIN THE RANGE ABOUT 0.1 TO ABOUT 10, AND AT A TEMPERATURE WITHIN THE RANGE ABOUT 400*F. TO ABOUT 825*F. TO PRODUCE FROM SAID LOWER BOILING FRACTION, A NAPHTHENIC NAPHTHA AND A MEDIUM BOILING RANGE PARAFFINIC STOCK AND TO PRODUCE FROM SAID HIGHER BOILING FRACTION A NAPHTHENIC NAPHTHA AND A HIGH RANGE PARAFFINIC STOCK.