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 distilled aromatic extract 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 disclosure discloses a process for obtaining an aromatic lean stream and an aromatic rich stream from a hydrocarbon feed, the process comprising: (a) obtaining a hydrocarbon feed; and (b) contacting the hydrocarbon feed with a solvent selected from a group consisting of alkyl aromatic hydrophilic polyethylene oxide, polyethylene glycols, and combinations thereof to obtain an aromatic lean stream and an aromatic rich stream. It further discloses a simultaneous process to obtain an aromatic lean stream and an aromatic rich stream. The present disclosure also discloses a process for obtaining de-aromatized kerosene from a hydrocarbon feed. Additionally, the present disclosure discloses a process for obtaining BTX from a hydrocarbon feed.

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 distilled aromatic extract 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.

A process for the treatment of oily hazardous solid materials such as for example spent bleaching earths. The process allows a safe and economical recovery of typically about 85% to 95% of the residual oil contained in such oily hazardous solid materials and transforms those ones into inert materials safe to transport, store, dispose of, or even makes them valuable for some applications. The process includes the production of a transportation slurry and at least one extraction slurry. The at least one extraction slurry is separated in at least one centrifuge decanter.

Systems and methods are provided for production of base stocks with a viscosity index of at least 120 and/or a sulfur content of 300 wppm or less and/or a kinematic viscosity at 100° C. of 3.0 cSt to 8.0 cSt by hydroconversion of a raffinate from aromatic extraction of a feed. The base stocks can further have a reduced content of 3+ ring naphthenes, such as 4.0 wt % or less, or 1.0 wt % or less. The base stocks can be produced by performing an elevated amount of feed conversion relative to 370° C. during hydroconversion of the raffinate, and optionally additional conversion during catalytic dewaxing of the hydroconverted raffinate. The base stocks can optionally be blended with additional base stocks and/or lubricant additives for production of lubricant compositions.

A method for re-refining used oils comprises contacting feedstock comprising purified used oil with extraction solvent to perform continuous liquid-liquid solvent extraction, to produce an extract stream comprising the extraction solvent and an extract dissolved in the extraction solvent. The feedstock and the extraction solvent are agitated by a variable speed agitator during the solvent extraction at a selected agitation speed. The extract is separated from the extraction solvent and subjected to a continuous flow liquid phase hydrogenation treatment to produce an oil product. A system for performing the method includes a purification unit for purifying the used oil; an extraction column for extracting the extract from the feedstock; and a continuous flow liquid phase hydrogenation unit. The extraction column comprises an agitator configured to agitate the feedstock and the extraction solvent flowing through the extraction column at a variable agitation speed.

Systems and processes for hydrotreating, splitting, and extracting a gasoil feed to produce a saturate-rich feedstock for olefin pyrolysis are provided. A gasoil feed is provided to a hydrotreating section to produce an ultralow sulfur distillate (ULSD) stream. The ULSD stream is provided to a splitter section to produce a light distillate stream and a heavy bottom stream. The light distillate stream is provided to an extraction section to produce an aromatic-rich extract phase and a saturate-rich raffinate phase. The raffinate phase is mixed with the heavy bottom stream to produce an olefin pyrolysis feedstock having a reduced BMCI as compared to the gasoil feed stream and the ULSD stream.

Systems and processes for hydrotreating, splitting, and extracting a gasoil feed to produce a saturate-rich feedstock for olefin pyrolysis are provided. A gasoil feed is provided to a hydrotreating section to produce an ultralow sulfur distillate (ULSD) stream. The ULSD stream is provided to a splitter section to produce a light distillate stream and a heavy bottom stream. The light distillate stream is provided to an extraction section to produce an aromatic-rich extract phase and a saturate-rich raffinate phase. The raffinate phase is mixed with the heavy bottom stream to produce an olefin pyrolysis feedstock having a reduced BMCI as compared to the gasoil feed stream and the ULSD stream.

A method for re-refining used oils comprises contacting feedstock comprising purified used oil with extraction solvent to perform continuous liquid-liquid solvent extraction, to produce an extract stream comprising the extraction solvent and an extract dissolved in the extraction solvent. The feedstock and the extraction solvent are agitated by a variable speed agitator during the solvent extraction at a selected agitation speed. The extract is separated from the extraction solvent and subjected to a continuous flow liquid phase hydrogenation treatment to produce an oil product. A system for performing the method includes a purification unit for purifying the used oil; an extraction column for extracting the extract from the feedstock; and a continuous flow liquid phase hydrogenation unit. The extraction column comprises an agitator configured to agitate the feedstock and the extraction solvent flowing through the extraction column at a variable agitation speed.

Systems and methods are provided for production of base stocks with a viscosity index of at least 120 and/or a sulfur content of 300 wppm or less and/or a kinematic viscosity at 100 C. of 3.0 cSt to 8.0 cSt by hydroconversion of a raffinate from aromatic extraction of a feed. The base stocks can further have a reduced content of 3+ ring naphthenes, such as 4.0 wt % or less, or 1.0 wt % or less. The base stocks can be produced by performing an elevated amount of feed conversion relative to 370 C. during hydroconversion of the raffinate, and optionally additional conversion during catalytic dewaxing of the hydroconverted raffinate. The base stocks can optionally be blended with additional base stocks and/or lubricant additives for production of lubricant compositions.