Patent ID: 8557105

Claim:
A method of hydrocracking a heavy hydrocarbon feedstock using well dispersed metal sulfide catalyst particles, the method comprising: providing a heavy hydrocarbon feedstock that includes a significant fraction of hydrocarbons having a boiling point above 343° C. and/or asphaltenes; blending a catalyst precursor with the heavy hydrocarbon feedstock at a temperature below a decomposition temperature of the catalyst precursor to form a conditioned feedstock composition that is thereafter heated to above the decomposition temperature to form well dispersed metal sulfide catalyst particles in situ within the heavy hydrocarbon feedstock; introducing into a first hydrocracking reactor, hydrogen (H 2 ) gas and the heavy hydrocarbon feedstock including the well dispersed metal sulfide catalyst particles already formed in situ within the heavy hydrocarbon feedstock and/or the conditioned feedstock composition to form the well dispersed metal sulfide catalyst particles in situ within the heavy hydrocarbon feedstock when heated to above the decomposition temperature of the catalyst precursor, the first hydrocracking reactor including a first gas-liquid two or more phase hydrocracking reactor having a first concentration of well dispersed metal sulfide catalyst particles that, together with the hydrogen gas, facilitate beneficial upgrading reactions within the heavy hydrocarbon feedstock; separating an effluent from the first hydrocracking reactor into a lower boiling volatile gaseous vapor fraction and a higher boiling liquid fraction in a manner so that the metal sulfide catalyst particles remain in the higher boiling liquid fraction and have increased concentration compared to a concentration of the well dispersed metal sulfide catalyst particles within the first hydrocracking reactor; and introducing at least a portion of the higher boiling liquid fraction containing the increased concentration of the metal sulfide catalyst particles and additional hydrogen (H 2 ) gas into a second gas-liquid two or more phase hydrocracking reactor, wherein the increased concentration of metal sulfide catalyst particles within the second hydrocracking reactor provides increased conversion and/or reaction rate and/or throughput.