Hydrocarbon hydroconversion where petroleum fractions are treated in parallel reactions while passing hydrogen serially through the reactors

Claim 1

A PROCESS FOR DESULFURIZING A SULFUR-CONTAINING HYDROCARBON OIL FEED WHICH COMPRISES SEPARATING SAID FEED INTO A PLURALITY OF SEPARATE PORTIONS OF SUBSTANTIALLY THE SAME BOILING RANGE, CONTACTING ONE PORTION OF SAID OIL FEED WITH A MASS OF HYDROGENATION CATALYST IN THE PRESENCE OF ADDED HYDROGEN UNDER SUITABLE DESULFURIZATION CONDITIONS INCLUDING SUPERATMOSPHERIC PRESSURE SUCH THAT A DESULFURIZED PRODUCT AND UNREACTED HYDROGEN ARE OBTAINED, SEPARATING HYDROGEN CONTAINING GAS FROM THE DESULFURIZED PRODUCT UNDER ESSENTIALLY THE PRESSURE OF REACTION, RECOVERING SAID DESULFURIZED PRODUCT, CONTACTING ANOTHER PORTION OF SAID HYDROCARBON OIL FEED WITH THE SEPARATED HYDROGEN-CONTAINING GAS UNDER LIQUID PHASE DESULFURIZATION CONDITIONS WITH A SECOND MASS OF HYDROGENATION CATALYST IN A SECOND DESULFURIZATION ZONE OPERATED AT A LOWER PRESSURE THAN THE FIRST DESULFURIZATION ZONE, THEREBY PROVIDING A PRESSURE DIFFERENTIAL SUFFICIENT FOR THE FLOW OF HYDROGEN-CONTAINING GAS FROM THE FIRST TO THE SECOND DESULFURIZATION ZONE.