Catalytic cracking of petroleum hydrocarbons with a clay treated catalyst

Claim 1

THE PROCESS WHICH COMPRISES PASSING A PETROLEUM FEEDSTOCK BOILING IN THE GAS OIL RANGE OR HIGHER IN ADMIXTURE WITH HYDROGEN TO A DESULPHURIZATION ZONE MAINTAINED UNDER ELEVATED TEMPERATURE AND PRESSURE, WHEREIN THE FEEDSTOCK IS TREATED IN THE PRESENCE, OF A SULPHUR-RESISTANT HYDROGENATION CATALYST TO CONVERT THE SULPHUR COMPOUNDS PRESENT IN THE FEEDSTOCK INTO HYDROGEN SULPHIDE, SEPARATING THE HYDROGEN SULPHIDE FROM THE TREATED FEEDSTOCK, PASSING THE DESULPHURIZED FEEDSTOCK TO A CATALYTIC CRACKING ZONE, WHEREIN THE DESULPHURIZED FEEDSTOCK IS CRACKED IN THE PRESENCE OF A CATALYST CONSISTING ESSENTIALLY OF A MONTMORILLONITE CLAY WHICH HAS BEEN HEATED TO A TEMPERATURE BETWEEN ABOUT 500* C. AND 700* C. TO REMOVE SUBSTANTIALLY COMPLETELY THE COMBINED HYDROXYL GROUPS WITHOUT CAUSING ANY PHYSICAL DISRUPTION OF THE CLAY, AND FROM WHICH CLAY, AS IT IS EMPLOYED IN THE CRACKING STEP, THE COMBINED HYDROXYL GROUPS ARE SUBSTANTIALLY COMPLETELY ABSENT, SAID TEMPERATURE BEING IN INVERSE RELATIONSHIP TO THE IRON OXIDE CONTENT PRESENT IN SAID CLAY SUCH THAT WHEN THE IRON OXIDE CONTENT IS LESS THAN 1.5%, THE TEMPERATURE WILL BE ABOUT 700* C., AND WHEN THE IRON OXIDE CONTENT IS MORE THAN 7%, THE TEMPERATURE WILL BE ABOUT 500* C., SEPARATING FROM THE PRODUCTS FROM SAID CATALYTIC CRACKING ZONE A GAS MIXTURE RICH IN HYDROGEN, AND PASSING SAID HYDROGENRICH GAS MIXTURE TO SAID DESULPHURIZATION ZONE TO CONSTITUTE THE WHOLE OF THE HYDROGEN FED TO SAID DESULPHURIZATION ZONE.