Patent ID: 7517446

Claim:
A method of upgrading a pre-existing fixed bed hydroprocessing system, comprising: (a) operating a pre-existing fixed bed hydroprocessing system comprising one or more fixed bed reactors, each of which comprises a liquid hydrocarbon phase, a bed of a porous supported catalyst as a solid phase, and hydrogen gas as a gaseous phase; (b) preparing a heavy oil feedstock containing asphaltenes by mixing an oil-soluble catalyst precursor composition with a hydrocarbon oil diluent at a temperature below which a substantial portion of the catalyst precursor composition begins to decompose to form a diluted catalyst precursor mixture and adding the diluted catalyst precursor mixture into the heavy oil feedstock to form a conditioned feedstock comprised of a mixture of the heavy oil feedstock and diluted catalyst precursor mixture; (c) heating the catalyst precursor composition within the heavy oil feedstock in order to decompose the catalyst precursor composition and form a colloidal or molecular catalyst having a particle size less than about 100 nm in situ within the heavy oil feedstock; (d) introducing the heavy oil feedstock from (b), optionally after (c), into at least one of: one or more fixed bed reactors of the pre-existing fixed bed hydroprocessing system to yield an upgraded fixed bed hydroprocessing system comprising one or more fixed bed reactors, the colloidal or molecular catalyst catalyzing hydroprocessing reactions involving the asphaltenes outside of the porous supported catalyst; or one or more slurry phase reactors to yield an upgraded fixed bed hydroprocessing system comprising one or more slurry phase reactors positioned upstream from one or more fixed bed reactors of the pre-existing fixed bed hydroprocessing system, the colloidal or molecular catalyst catalyzing hydroprocessing reactions that reduce or eliminate the asphaltenes from the heavy oil feedstock prior to introducing an upgraded feedstock from the one or more slurry phase reactors into one or more of the fixed bed reactors; and (e) operating the upgraded fixed bed hydroprocessing system to form a hydroprocessed feedstock.