Removal of naphthenic acids by hydrogenation with a molybdenum oxidesilica alumina catalyst

Claim 1

THE PROCESS FOR PREFERENTIALLY HYDROGENATING NAPHTHENIC ACIDS IN THE PRESENCE OF SULFUR COMPOUNDS IN A LUBRICATING OIL PORTION WHICH COMPRISES SUBJECTING SAID MIXTURE TO THE ACTION OF HYDROGEN AT A TEMPERATURE OF ABOUT 450* TO 600*F., AT A PRESSURE OF ABOUT 100 TO 500 P.S.I.G., A SPACE VELOCITY OF ABOUT 0.5 TO 2.0 LV./V./HR. AND WITH ABOUT 1000 TO 3000 S.C.F. OF HYDROGEN PER BARREL OF SAID PETROLEUM OIL MIXTURE, IN THE PRESENCE OF A CATALYST CONSISTING OF ABOUT 2.0 TO 10.0 WEIGHT PERCENT OF MOLYBDENUM OXIDE ON A SILICA-ALUMINA SUPPORT, SAID CATALYST HAVING A REVERSIBLE WATER CONTENT OF LESS THAN 1.0 WEIGHT PERCENT, MAINTAINING THE ACTIVITY OF SAID CATALYST BY PERIODICALLY CONTACTING SAID CATALYST IN THE ABSENCE OF SAID PETROLEUM OIL MIXTURE WITH AN OXYGEN-CONTAINING ATMOSPHERE AT A TEMPERATURE OF AT LEAST ABOUT 1000*F. FOR A PERIOD OF ABOUT 3 HOURS, AND RECOVERING A HYDROGENATED PRODUCT HAVING A NEUTRALIZATION NUMBER OF BELOW ABOUT 0.03 AND SUBSTANTIALLY THE SAME SULFUR CONTENT.