Patent ID: 8703637

Claim:
In a process for preparing a slurry catalyst for use in upgrading heavy oil feedstock comprising: providing a first metal precursor comprising a Primary metal selected from Group VIB metals and a promoter metal precursor comprising at least a Promoter metal selected from Group IVB metals, Group VIII metals, Group IIB metals and combinations thereof, for a Promoter metal to a Primary metal weight ratio ranging from 1-50 wt. %; sulfiding the first metal precursor and the promoter metal precursor separately, concurrently, or together, forming a promoted sulfided catalyst precursor; and mixing the promoted sulfided catalyst precursor with a hydrocarbon diluent forming a slurry catalyst having an to average particle size of 1 to 300 μm, the improvement comprising: apportioning at least one of the metal precursors into a first portion and a second portion at a ratio of first portion to second portion ranging from 1:10 to 10:1; employing the first portion in the sulfidation step to form the promoted sulfided catalyst precursor; and mixing the second portion with the promoted sulfided catalyst precursor before, during, or after the mixing step with a hydrocarbon diluent to form the slurry catalyst.