Methods for increasing catalyst concentration in heavy oil and/or coal resid hydrocracker

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 heavy hydrocarbon feedstock composition;
• introducing the conditioned heavy hydrocarbon feedstock composition into a first gas-liquid two or more phase hydrocracking reactor and heating the conditioned heavy hydrocarbon feedstock composition within the first hydrocracking reactor to convert the catalyst precursor into well dispersed metal sulfide catalyst particles in situ within the heavy hydrocarbon feedstock, the first gas-liquid two or more phase hydrocracking reactor having a first concentration of metal sulfide catalyst particles, operating at a first pressure, and producing an effluent;
• introducing the effluent produced from the first hydrocracking reactor into a pressure differential interstage separator which induces a significant pressure drop so as to separate the effluent into a lower boiling volatile gaseous vapor fraction and a higher boiling liquid fraction;
• and
• introducing at least a portion of the higher boiling liquid fraction into a second gas-liquid two or more phase hydrocracking reactor having a second concentration of metal sulfide catalyst particles that is greater than the first concentration of metal sulfide catalyst particles within the first hydrocracking reactor and operating at a second pressure that is less than the first pressure, wherein the pressure drop of the pressure differential interstage separator is determined at least in part by a difference between the first and second pressures.

A method of hydrocracking a heavy hydrocarbon feedstock using well dispersed metal sulfide catalyst particles, the method comprising:

• mixing a catalyst precursor into a heavy hydrocarbon feedstock to yield a conditioned heavy hydrocarbon feedstock composition comprised of the heavy hydrocarbon and the catalyst precursor;
• heating the conditioned heavy hydrocarbon feedstock composition to yield a heavy hydrocarbon feedstock that includes well dispersed metal sulfide catalyst particles formed in situ within the heavy hydrocarbon feedstock;
• introducing the heavy hydrocarbon feedstock and well dispersed metal sulfide catalyst particles into a first gas-liquid two or more phase hydrocracking reactor, the first gas-liquid two or more phase hydrocracking reactor having a first concentration of metal sulfide catalyst particles, operating at a first pressure, and producing an effluent;
• introducing the effluent produced from said first hydrocracking reactor into a pressure differential interstage separator which induces a significant pressure drop so as to separate the effluent into a lower boiling volatile gaseous vapor fraction and a higher boiling liquid fraction;
• and
• introducing at least a portion of the higher boiling liquid fraction into a second gas-liquid two or more phase hydrocracking reactor having a second concentration of metal sulfide catalyst particles that is greater than the first concentration of metal sulfide catalyst particles within the first hydrocracking reactor and operating at a second pressure that is less than the first pressure, wherein the pressure drop of the pressure differential interstage separator is determined at least in part by a difference between the first and second pressures.