Catalytic desulfurization of gas oil

Claim 1

IN A CONTINUOUS PROCESS FOR THE HYDROCATALYTIC DESULPHURIZATION OF A SULPHUR-ANDNAPHTHENE-CONTAINING PETROLEUM OIL BOILING SUBSTANTIALLY IN THE GAS OIL RANGE WHEREIN THE OIL IS CONTACTED IN VAPOR FORM IN A REACTION ZONE AT AN ELEVATED TEMPERATURE AND PRESSURE IN THE PRESENCE OF HYDROGEN WITH A DEHYDROGENATION-HYDROGENATION CATALYST WHICH IS IMMUNE TO SULPHUR POISONING AND COMBINES ACTIVITY FOR THE DEHYDROGENATION OF NAPHTHENES IN SAID OIL TO AROMATICS WITH ACTIVITY FOR THE HYDROGENATION OF ORGANICALLY COMBINED SULPHUR IN SAID OIL TO HYDROGEN SULPHIDE, THE METHOD OF OPERATING THE PROCESS SO THAT IT WILL BE SELF-SUPPORTING WITH RESPECT TO THE AMOUNT OF HYDROGEN NEEDED AND PRODUCE A DESULPHURIZED PRODUCT OIL HAVING, EXCEPT FOR LOWERED SULPHUR CONTENT, PROPERTIES AND BOILING RANGE SUBSTANTIALLY THE SAME AS THE FEEDSTOCK, COMPRISING THE STEPS OF PASSING THE GAS OIL TO BE TREATED THROUGH SAID REACTION ZONE AND CONTACTING THE GAS OIL THEREIN WITH SAID CATALYST AND WITH HYDROGEN DERIVED SOLELY FROM THE OIL, MAINTAINING A SELECTED TEMPERATURE IN SAID ZONE BETWEEN ABAOUT 750* F. TO ABOUT 820* F. AT WHICH HYDROGEN IS CONTINUOUSLY PRODUCED FROM SAID OIL, MAINTAINING A SELECTED PRESSURE IN SAID ZONE BETWEEN ABOUT 50 TO ABOUT 200 LBS./SQ. IN. GAUGE, SAID SELECTED TEMPERATURE AND PRESSURE BEING CORRELATED TO PROVIDE, FROM THE DEHYDROGENATION OF NAPHTHENES CONTAINED IN SAID OIL, A NET PRODUCTION OF HYDROGEN AT LEAST SUFFICIENT TO MAINTAIN THE PRESSURE IN SAID ZONE SUBSTANTIALLY CONSTANT SEPARATING A HYDROGEN-RICH GAS MIXTURE FROM THE TREATED GAS OIL, RECYCLING SAID HYDROGEN-RICH GAS MIXTURE TO THE REACTION ZONE TO CONSTITUTE THE WHOLE OF THE HYDROGEN SUPPLIED TO SAID ZONE, THE HYDROGEN RECYCLE RATE BEING SUFFICIENT TO MAINTAIN THE NECESSARY PARTIAL PRESSURE OF HYDROGEN IN SAID ZONE, AND RECOVERING THE DESIRED PRODUCT OIL.