Catalytic desulfurization of petroleum hydrocarbons

Claim 1

IN A CONTINUOUS PROCESS FOR THE HYDROCATALYTIC DESULPHURIZATION OF A SULPHUR-ANDNAPHTHENE-CONTAINING PETROLEUM DISTILLATE BOILING ABOVE 375* C. WHEREIN THE DISTILLATE IS CONTACTED IN VAPOR FORM IN A REACTION ZONE AT AN ELEVATED TEMPERATURE AND PRESSURE IN TH PRESENCE OF HYDROGEN WITH A DEHYDROGENATION-HYDROGENATION CATALYST WHICH IS IMMUNE TO SULPHUR POISONING AND COMBINES ACTIVITY FOR THE DEHYDROGENATION OF NAPTHENES IN SAID DISTILLATE TO AROMATICS WITH ACTIVITY FOR THE HYDROGENATION OF ORIGINICALLY COMBINED SULPHUR IN THE DISTILLATE TO HYDROGEN SULPHIDE, THE METHOD OF OPERATING THE PROCESS SO THAT IT WILL BE SELF-SUPPORTING WITH RESPECT TO THE HYDROGEN NEEDED AND PRODUCE, AS PRODUCT, A DESULPHURIZED DISTILLATE WHOSE NATURE, EXCEPT FOR LOWERED SULPHUR CONTENT, IS SUBSTANTIALLY THE SAME AS THE FEEDSTOCK, WHICH METHOD COMPRISES THE STEPS OF PASSING THE DISTILLATE TO BE TREATED THROUGH SAID REACTION ZONE IN VAPOR FORM AND CONTACTING THE DISTILLATE THEREIN WITH SAID CATALYST AND WITH HYDROGEN DERIVED SOLELY FROM THE DISTILLATE: MAINTAINING A SELECTED TEMPERATURE IN SAID ZONE BETWEEN ABOUT 750* F. TO ABOUT 800* F. AT WHICH HYDROGEN IS CONTINUOUSLY PRODUCED FROM SAID DISTILLATE BY DEHYDROGENATION OF NAPHTHENES THEREIN TO AROMATICS; 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 A CONTINUOUS NET PRODUCTION OF HYDROGEN AT LEAST EQUAL TO BUT NOT SUBSTANTIALLY IN EXCESS OF THAT REQUIRED TO EFFECT CONVERSION OF SAID ORGANIC SULPHUR COMPOUNDS TO HYDROGEN SULPHIDE AND TO MAINTAIN THE PRESSURE IN SAID ZONE; SEPARATING A HYDROGEN-RICH GAS MIXTURE FROM THE TREATED DISTILLATE; RECYCLING SAID HYDROGEN-RICH GAS MIXTURE TO SAID REACTION ZONE TO CONSTITUTE THE WHOLE OF THE HYDROGEN SUPPLIED TO SAISD ZONE, THE HYDROGEN-RICH GAS MIXTURE RECYCLE RATE BEING SUFFICIENT TO MAINTAIN THE NECESSARY PARTIAL PRESSURE OF HYDROGEN IN SAID ZONE; AND RECOVERING THE DESIRED PRODUCT DISTILLATE FROM THE RESIDUE OF SAID SEPARATING OPERATION.