Systems and methods are provided for hydroprocessing a petroleum fraction, such as a bottoms fraction from a fuels hydrocracking process, to generate a lubricant base oil. The aromatic content of such a petroleum fraction can be reduced using a aromatic saturation stage with multiple catalyst beds, or alternatively using a reactor (or reactors) with multiple aromatic saturation stages. The catalysts in the various beds or stages can be selected to provide different types of aromatic saturation activity. An initial bed or stage can provide activity for saturation of 1-ring aromatics in the petroleum fraction. One or more subsequent beds or stages, operating at successively lower temperature, can then be used to reduce the multiple-ring aromatic content of the petroleum fraction.

Systems and methods are provided for hydroprocessing a petroleum fraction, such as a bottoms fraction from a fuels hydrocracking process, to generate a lubricant base oil. The aromatic content of such a petroleum fraction can be reduced using a aromatic saturation stage with multiple catalyst beds, or alternatively using a reactor (or reactors) with multiple aromatic saturation stages. The catalysts in the various beds or stages can be selected to provide different types of aromatic saturation activity. An initial bed or stage can provide activity for saturation of 1-ring aromatics in the petroleum fraction. One or more subsequent beds or stages, operating at successively lower temperature, can then be used to reduce the multiple-ring aromatic content of the petroleum fraction.

Refinery processes, systems, and compositions for making an aromatic blending component for fuel oil, and a fuel oil blend using the same. Valuable hydrocarbons like kerosene can be reduced or eliminated from fuel oil blends by adding certain aromatic blending components derived from the aromatic bottoms stream of an aromatic recovery complex. The aromatic blending component can be used in lieu of more costly hydrocarbon streams to decrease the overall viscosity of the fuel oil blend without adding sulfur.

Marine diesel fuel/fuel blending component compositions and fuel oil/fuel blending component compositions are provided that are derived from crude oils having high naphthenes to aromatics volume and/or weight ratios and a low sulfur content. In addition to having a high naphthenes to aromatics ratio, a low sulfur content, and a low but substantial content of aromatics, such fuels and/or fuel blending components can have a reduced or minimized carbon intensity relative to fuels derived from conventional sources. The unexpected ratio of naphthenes to aromatics contributes to the fuels and/or fuel blending components further having additional unexpected properties, including low density, low kinematic viscosity, and/or high energy density.

A dividing wall column system for producing hexane includes a dividing wall column including a dividing wall that divides the dividing wall column at least partially into a first side and a second side, with one side of the first and second sides configured to operate as a deisohexanizer column and the other side of the first and second side configured to operate as a hexane column to produce hexane.

Processes herein may be used to thermally crack various hydrocarbon feeds, and may eliminate the refinery altogether while making the crude to chemicals process very flexible in terms of crude. In embodiments herein, crude is progressively separated into at least light and heavy fractions. Depending on the quality of the light and heavy fractions, these are routed to one of three upgrading operations, including a fixed bed hydroconversion unit, a fluidized catalytic conversion unit, or a residue hydrocracking unit that may utilize an ebullated bed reactor. Products from the upgrading operations may be used as feed to a steam cracker.

Processes herein may be used to thermally crack various hydrocarbon feeds, and may eliminate the refinery altogether while making the crude to chemicals process very flexible in terms of crude. In embodiments herein, crude is progressively separated into at least light and heavy fractions. Depending on the quality of the light and heavy fractions, these are routed to one of three upgrading operations, including a fixed bed hydroconversion unit, a fluidized catalytic conversion unit, or a residue hydrocracking unit that may utilize an ebullated bed reactor. Products from the upgrading operations may be used as feed to a steam cracker.

Naphthenic process oils are made by blending one or more naphthenic vacuum gas oils in one or more viscosity ranges with a high C.sub.A content ethylene cracker bottoms, slurry oil, heavy cycle oil or light cycle oil feedstock to provide at least one blended oil, and hydrotreating the at least one blended oil to provide an enhanced C.sub.A content naphthenic process oil. The order of the vacuum distillation and blending steps may be reversed.

Naphthenic process oils are made by blending one or more naphthenic vacuum gas oils in one or more viscosity ranges with a high C.sub.A content ethylene cracker bottoms, slurry oil, heavy cycle oil or light cycle oil feedstock to provide at least one blended oil, and hydrotreating the at least one blended oil to provide an enhanced C.sub.A content naphthenic process oil. The order of the vacuum distillation and blending steps may be reversed.

The present invention discloses an integrated process scheme for producing (i) high-octane gasoline blending stream (ii) high aromatic heavy naphtha stream which is a suitable feedstock for benzene, toluene, and xylene (BTX) production and (iii) high cetane ultra-low sulphur diesel (ULSD) stream suitable for blending in refinery diesel pool.