Platinum-containing catalysts and method of preparation thereof

Claim 1

A PROCESS FOR REFORMING A GASOLINE FRACTION TO INCREASE THE ANTI-KNOCK VALUE THEREOF WHICH COMPRISES SUBJECTING SAID FRACTION TO CONTACT AT A TEMPERATURE WITHIN THE RANGE OF 600 TO 1000*F., A PRESSURE OF FROM 100 TO 1000 POUNDS PER SQUARE INCH AND A LIQUID HOURLY SPACE VELOCITY OF FROM 0.1 TO 10, IN THE PRESENCE OF FROM 1 TO 20 MOLS. OF HYDROGEN PER MOL. OF HYDROCARBON WITH A CATALYST PREPARED BY CONTACTING AT AN ELEVATED TEMPERATURE A SILICA-ALUMINA COMPONENT WITH AN AQUEOUS SOLUTION OF PLATINOUS TETRAMMINOHYDROXIDE TO IMPREGNATE THE SILICAALUMINA, DRYING THE IMPREGNATED SILICA-ALUMINA AND CONVERTING THE PLATINUM IMPREGNATED ON THE SILICA-ALUMINA TO THE METAL, THE PLATINUM BEING IN AN AMOUNT BETWEEN 0.1 TO 2.5 PERCENT BY WEIGHT OF THE FINAL CATALYST, SAID SILICAALUMINA COMPONENT BEING CHARACTERIZED BY HAVING A CATALYTIC CRACKING ACTIVITY WITHIN A RANGE BETWEEN 20 AND 65 AS COMPARED WITH A THERETICAL MAXIMUM CATALYTIC CRACKING ACTIVITY OF 100 AND A PRACTICABLE MAXIMUM CATALYTIC CRACKING ACTIVITY OF BETWEEN 90 AND 95 ON A DISTILLATE-PLUSLOSS SCALE FOR THE MEASUREMENT OF THE CATALYTIC CRACKING ACTIVITY OF A CRACKING CATALYST.