Patent ID: 8034232

Claim:
A method of hydrocracking a heavy oil feedstock using a colloidally or molecularly dispersed catalyst comprising: providing a heavy oil 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 oil 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 a colloidally or molecularly dispersed catalyst in situ within the heavy oil feedstock; introducing into a first hydrocracking reactor, hydrogen (H 2 ) gas and the heavy oil feedstock including the colloidally or molecularly dispersed catalyst already formed in situ within the heavy oil feedstock and/or the conditioned feedstock composition to form the colloidally or molecularly dispersed catalyst in situ within the heavy oil 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 colloidally or molecularly dispersed catalyst that, together with the hydrogen gas, facilitate beneficial upgrading reactions within the heavy oil 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 colloidally or molecularly dispersed catalyst remains in the higher boiling liquid fraction and has increased concentration compared to a concentration of the colloidally or molecularly dispersed catalyst within the first hydrocracking reactor; and introducing at least a portion of the higher boiling liquid fraction containing the increased concentration of the colloidally or molecularly dispersed catalyst and additional hydrogen (H 2 ) gas into a second gas-liquid two or more phase hydrocracking reactor, wherein the increased concentration of colloidally or molecularly dispersed catalyst within the second hydrocracking reactor provides increased conversion and/or reaction rate and/or throughput.