Patent ID: 7238273

Claim:
A process for the hydroconversion of heavy oils, which employs a catalyst which is prepared by the following steps: (a) mixing a Group VI B metal oxide and aqueous ammonia to form a Group VI metal compound aqueous mixture; (b) sulfiding, in an initial reactor, the aqueous mixture of step (a) with a gas comprising hydrogen sulfide to a dosage greater than 8 SCF of hydrogen sulfide per pound of Group VI B metal to form a slurry; (c) promoting the slurry with a Group VIII metal; (d) mixing the slurry of step (c) with a first hydrocarbon oil having a viscosity of at least 2 cSt @ 212° F. to form Mixture X; (e) combining Mixture X with hydrogen gas and a second hydrocarbon oil in a second reaction zone, the second hydrocarbon oil having a boiling point in the range from 50° F. to 300° F. and having a lower viscosity than the first hydrocarbon oil, thereby forming an active catalyst composition admixed with a light hydrocarbon; and (f) recovering the active catalyst composition by separation from the second hydrocarbon oil, wherein said catalyst, a hydrogen-containing gas and the heavy oil to be converted are added, at elevated temperature and pressure, to a fixed or ebullating bed.