A method for recovering synthetic oils from a feed stream, the method comprising separating at least a portion of the non-synthetic oil constituents from a commingled stream to produce a partially purified synthetic oil stream and one or more contaminant streams. Extracting at least a portion of the synthetic oil from the partially purified synthetic oil stream to produce a synthetic oil stream and a second contaminant stream.

A method for recovering synthetic oils from a feed stream, the method comprising separating at least a portion of the non-synthetic oil constituents from a commingled stream to produce a partially purified synthetic oil stream and one or more contaminant streams. Extracting at least a portion of the synthetic oil from the partially purified synthetic oil stream to produce a synthetic oil stream and a second contaminant stream.

A method for recovering synthetic oils from a feed stream, the method comprising separating at least a portion of the non-synthetic oil constituents from a commingled stream to produce a partially purified synthetic oil stream and one or more contaminant streams. Extracting at least a portion of the synthetic oil from the partially purified synthetic oil stream to produce a synthetic oil stream and a second contaminant stream.

A method for recovering synthetic oils from a feed stream, the method comprising separating at least a portion of the non-synthetic oil constituents from a commingled stream to produce a partially purified synthetic oil stream and one or more contaminant streams. Extracting at least a portion of the synthetic oil from the partially purified synthetic oil stream to produce a synthetic oil stream and a second contaminant stream.

Mercury is removed from a mercury-containing hydrocarbon fluid feed by utilizing ionic liquids. The mercury-containing hydrocarbon fluid feed is contacted with a metallate salt immobilized on a solid support material. A hydrocarbon fluid product having a reduced mercury content compared to the mercury-containing fluid feed is separated from the ionic liquid.

Mercury is removed from a mercury-containing hydrocarbon fluid feed by utilizing ionic liquids. The mercury-containing hydrocarbon fluid feed is contacted with a metallate salt immobilized on a solid support material. A hydrocarbon fluid product having a reduced mercury content compared to the mercury-containing fluid feed is separated from the ionic liquid.

A process for the treatment of a hydrocracking unit bottoms recycle stream, and preferably the fresh hydrocracker feed to remove heavy poly-nuclear aromatic (HPNA) compounds and HPNA precursors employs, in the alternative, an adsorption step which removes most of the HPNA compounds followed by an ionic liquid extraction step to remove the remaining HPNA compounds, or a first ionic liquid extraction step which removes most of the HPNA compounds followed by an adsorption step to remove the remaining HPNA compounds. Ionic liquids of the general formula Q.sup.+A.sup. are identified for use in the process; organic polar solvents are identified for removal of the HPNA compounds in solution. Suitable adsorbents are identified for use in packed bed or slurry bed columns that operate within specified temperature and pressure ranges.

A process for the treatment of a hydrocracking unit bottoms recycle stream, and preferably the fresh hydrocracker feed to remove heavy poly-nuclear aromatic (HPNA) compounds and HPNA precursors employs, in the alternative, an adsorption step which removes most of the HPNA compounds followed by an ionic liquid extraction step to remove the remaining HPNA compounds, or a first ionic liquid extraction step which removes most of the HPNA compounds followed by an adsorption step to remove the remaining HPNA compounds. Ionic liquids of the general formula Q.sup.+A.sup. are identified for use in the process; organic polar solvents are identified for removal of the HPNA compounds in solution. Suitable adsorbents are identified for use in packed bed or slurry bed columns that operate within specified temperature and pressure ranges.

A method for producing ILSAC GF5 or higher compatible oils from used oil, comprising separating material having a boiling point less than about 350 F. from recovered oil to produce de-volatized fraction and light oil fraction. Separating material with a boiling point greater than about 350 F. and less than about 650 F. from the de-volatized oil fraction to produce fuel oil fraction and heavy oil fraction. Separating material with a boiling point greater than about 1200 F. from the heavy oil fraction to produce partially purified oil fraction and residual fraction. Treating the partially purified oil fraction to separate it into purified oil fraction and contaminant fraction. Hydrogenating the contaminant fraction to remove predetermined compounds, further saturating the fraction and thereby creating a saturated oil fraction. Fractionating the saturated oil stream to produce one or more of naphtha fraction, diesel oil fraction and base oil fraction.

A method for producing ILSAC GF5 or higher compatible oils from used oil, comprising separating material having a boiling point less than about 350 F. from recovered oil to produce de-volatized fraction and light oil fraction. Separating material with a boiling point greater than about 350 F. and less than about 650 F. from the de-volatized oil fraction to produce fuel oil fraction and heavy oil fraction. Separating material with a boiling point greater than about 1200 F. from the heavy oil fraction to produce partially purified oil fraction and residual fraction. Treating the partially purified oil fraction to separate it into purified oil fraction and contaminant fraction. Hydrogenating the contaminant fraction to remove predetermined compounds, further saturating the fraction and thereby creating a saturated oil fraction. Fractionating the saturated oil stream to produce one or more of naphtha fraction, diesel oil fraction and base oil fraction.