Methods for hydrocracking a heavy oil feedstock using an in situ colloidal or molecular catalyst and recycling the colloidal or molecular catalyst

A method of upgrading an existing ebullated bed hydroprocessing system in order to reduce formation of coke and/or sediment, comprising:

• (a) providing an existing ebullated bed hydroprocessing system comprising one or more ebullated bed reactors, each comprising a liquid hydrocarbon phase, a solid phase comprised of an expanded bed of a porous supported catalyst, a gaseous phase comprised of hydrogen gas, and catalyst free zones above and below the expanded bed of the porous supported catalyst;
• (b) mixing an oil-soluble catalyst precursor with a hydrocarbon oil diluent at a temperature below which a substantial portion of the catalyst precursor begins to decompose to form a diluted catalyst precursor mixture;
• (c) after forming the diluted catalyst precursor mixture and prior to heating the catalyst precursor to effect decomposition of the catalyst precursor and in situ formation of active colloidal or molecular catalyst, mixing the diluted catalyst precursor mixture with a heavy oil feedstock to form a conditioned feedstock comprised of a mixture of the heavy oil feedstock and diluted catalyst precursor mixture in order to further dilute the catalyst precursor with the heavy oil feedstock prior to decomposition of the catalyst precursor and in situ formation of a colloidal or molecular catalyst within the heavy oil feedstock;
• (d) heating the catalyst precursor within the heavy oil feedstock in order to decompose the catalyst precursor and form a colloidal or molecular catalyst in situ within the heavy oil feedstock;
• (e) introducing the heavy oil feedstock from (c), optionally after (d), into at least one ebullated bed reactor of the existing ebullated bed hydroprocessing system to form an upgraded ebullated bed hydroprocessing system comprising the one or more ebullated bed reactors and in which the colloidal or molecular catalyst is dispersed throughout the liquid hydrocarbon phase, including what were previously catalyst free zones in the at least one ebullated bed reactor of the existing ebullated bed hydroprocessing system;
• and
• (f) operating the upgraded ebullated bed hydroprocessing system to form a hydroprocessed material, the upgraded ebullated bed hydroprocessing system operating with higher asphaltene conversion and/or increased longevity of porous supported catalyst compared to the existing ebullated bed hydroprocessing system, the colloidal or molecular catalyst catalyzing beneficial hydroprocessing reactions throughout the liquid hydrocarbon phase.

A method of upgrading an existing ebullated bed hydroprocessing system in order to reduce formation of coke and/or sediment, comprising:

• (a) operating an existing ebullated bed hydroprocessing system comprising one or more ebullated bed reactors, each of which comprises a liquid hydrocarbon phase, a solid phase comprised of an expanded bed of a porous supported catalyst, a gaseous phase comprised of hydrogen gas, and catalyst free zones above and below the expanded bed of the porous supported catalyst;
• and
• (b) following (a), constructing and operating one or more slurry phase reactors upstream from at least one ebullated bed reactor of the existing ebullated bed hydroprocessing system in order to form an upgraded feedstock from a heavy oil feedstock, the one or more slurry phase reactors comprising a heavy oil feedstock and a colloidal or molecular catalyst a sole or primary hydroprocessing catalyst, the colloidal or molecular catalyst being prepared by:
• (1) mixing a catalyst precursor with the heavy oil feedstock prior to heating the catalyst precursor to effect decomposition of the catalyst precursor and in situ formation of active colloidal or molecular catalyst so as to form a conditioned feedstock comprised of the heavy oil feedstock and diluted catalyst precursor;
• and
• (2) heating the conditioned feedstock in order to decompose the catalyst precursor and form the colloidal or molecular catalyst in situ within the heavy oil feedstock;
• and
• (c) introducing the upgraded feedstock and colloidal or molecular catalyst from the one or more slurry phase reactors into at least one ebullated bed reactor of the existing ebullated bed hydroprocessing system to form an upgraded ebullated bed hydroprocessing system comprising the one or more slurry phase reactors in combination with the one or more ebullated bed reactors, the colloidal or molecular catalyst catalyzing beneficial hydroprocessing reactions throughout the liquid hydrocarbon phase, including what were previously catalyst free zones in the existing ebullated bed hydroprocessing system, thereby increasing asphaltene conversion and/or increasing longevity of the porous supported catalyst compared to the existing ebullated bed hydroprocessing system.

A method of upgrading an existing ebullated bed hydroprocessing system, comprising:

• (a) operating an existing ebullated bed hydroprocessing system comprising one or more ebullated bed reactors, each of which comprises a liquid hydrocarbon phase, a solid phase comprised of an expanded bed of a porous supported catalyst, a gaseous phase comprised of hydrogen gas, and catalyst free zones above and below the expanded bed of the porous supported catalyst;
• and
• (b) following (a), converting at least one of the one or more ebullated bed reactors of the existing ebullated bed hydroprocessing system into a slurry phase reactor by replacing the porous supported catalyst with a molecular or colloidal catalyst as sole hydroprocessing catalyst to form an upgraded ebullated bed hydroprocessing system comprising one or more slurry phase reactors in combination with one or more ebullated bed reactors, the one or more slurry phase reactors comprising a liquid phase comprised of a heavy oil feedstock and the colloidal or molecular catalyst and a gaseous phase comprised of hydrogen gas, the colloidal or molecular catalyst catalyzing beneficial hydroprocessing reactions throughout the liquid hydrocarbon phase, including what were previously catalyst free zones in the existing ebullated bed hydroprocessing system, thereby increasing asphaltene conversion and/or reducing formation of coke or sediment in the upgraded ebullated bed hydroprocessing system compared to the existing ebullated bed hydroprocessing system, the colloidal or molecular catalyst being prepared by:
• (1) mixing a catalyst precursor with the heavy oil feedstock prior to heating the catalyst precursor to effect decomposition of the catalyst precursor and in situ formation of active colloidal or molecular catalyst so as to form a conditioned feedstock comprised of the heavy oil feedstock and diluted catalyst precursor;
• and
• (2) heating the conditioned feedstock in order to decompose the catalyst precursor and form the colloidal or molecular catalyst in situ within the heavy oil feedstock.

A method of hydroprocessing a heavy oil feedstock, comprising:

• operating an ebullated bed hydroprocessing system operating at hydrocracking conditions and comprising a plurality of ebullated bed reactors, each ebullated bed reactor comprising:
• a solid phase comprised of a porous supported catalyst within an expanded catalyst bed;
• a gaseous phase comprised of hydrogen;
• supported catalyst free zones above and below the expanded catalyst bed that are devoid of the porous supported catalyst;
• a liquid phase circulating throughout the expanded catalyst bed and the supported catalyst free zones, the liquid phase comprising liquid hydrocarbons provided by a heavy oil feedstock and having a boiling point greater than about 650° F.;
• a colloidal or molecular catalyst dispersed throughout the liquid phase and catalyzing reactions between the hydrogen and free radicals formed from the heavy oil feedstock throughout the liquid phase, including the supported catalyst free zones, to yield an upgraded hydrocarbon material while increasing asphaltene conversion and/or reducing or eliminating formation of coke precursors and sediment within the ebullated bed reactor compared to an ebullated bed reactor in the absence of the molecular or colloidal catalyst;
• prior to introducing a heavy oil feedstock into a first ebullated bed reactor, blending a catalyst precursor with the heavy oil feedstock so as to form a conditioned feedstock comprised of the heavy oil feedstock and catalyst precursor in order to dilute the catalyst precursor with the heavy oil feedstock prior to heating the catalyst precursor to effect substantial decomposition of the catalyst precursor and in situ formation of active colloidal or molecular catalyst within the heavy oil feedstock;
• heating the conditioned feedstock upstream from or within the first ebullated bed reactor in order to decompose the catalyst precursor and form the colloidal or molecular catalyst in situ within the heavy oil feedstock;
• introducing at least a portion of a liquid hydrocarbon product from the first ebullated bed reactor into a second ebullated bed reactor downstream from the first ebullated bed reactor, the liquid hydrocarbon product including residual colloidal or molecular catalyst from the first ebullated bed reactor;
• and
• providing supplemental colloidal or molecular catalyst to the second ebullated bed reactor in addition to the residual colloidal or molecular catalyst from the first ebullated bed reactor.