Hydrodenitrogenation with high molybdenum content catalyst

Claim 1

A PROCESS FOR HYDROREFINING A MINERAL OIL FEEDSTOCK CONTAINING ORGANIC NITROGEN COMPOUNDS TO EFFECT AT LEAST ABOUT 85% DENITROGENATION THEREOF, WHICH COMPRISES CONTACTING SAID FEEDSTOCK PLUS ADDED HYDROGEN WITH A HYDROREFINING CATALYST AT AN INITIAL HYDROREFINING TEMPERATURE BETWEEN ABOUT 600* AND 725*F., A SPACE VELOCITY BETWEEN ABOUT 0.5 AND 3.0 AND A PRESSURE BETWEEN ABOUT 400 AND 2,000 P.S.I.G., PERIODICALLY RAISING THE TEMPERATURE OF SAID CONTACTING IN ORDER TO MAINTAIN A SUBSTANTIALLY CONSTANT DEGREE OF DENITROGENATION, CONTINUING SAID CONTACTING AT INCREMENTIALLY RISING TEMPERATURE UNTIL A TERMAL TEMPERATURE BETWEEN ABOUT 775*-850*F. IS REACHED, WHEREBY A RUN LENGTH OF AT LEAST ABOUT 60 DAYS IS OBTAINED IN WHICH AT LEAST ABOUT 85% DENITROGENATION IS MAINTAINED THROUGHOUT, SAID CATALYST COMPRISING BETWEEN ABOUT 0.7% AND 4% BY WEIGHT OF COBALT AND BETWEEN ABOUT 8.3% AND 10% BY WEIGHT OF MOLYBDENUM INTIMATELY DISTRIBUTED AND SUPPORTED UPON A CARRIER WHICH IS ESSENTIALLY ACTIVATED ALUMINA, SAID CATALYST HAVING BEEN PREPARED BY ALTERNATE IMPREGNATION WITH SEPARATE AQUEOUS SOLUTIONS OF AMMONIUM MOLYBDATE AND A SOLUBLE COBALT SALT, AND HAVING BEEN PRE-SULFIDED PRIOR TO USE IN SAID HYDROREFINING PROCESS BY CONTACT WITH A REACTIVE SULFIDING AGENT UNDER NON-COKING CONDITIONS, THE CO/MO ATOMIC RATIO IN SAID BEING BETWEEN ABOUT 0.2 AND 0.6.