Applying a sufficient quantity of an Alkali metal or an Alkaline earth metal to a fluid in a stripping process loop 106 to form a first intermediary compound and thereby, to strip the undesired element from the process fluid 102. The first intermediary compound 130 is processed in a recovery process loop 110 to recover the Alkali metal or Alkaline earth metal. The recovered Alkali metal or Alkaline earth metal is then re-introduced to an additional quantity of process fluid to strip and clean the undesired element from the additional quantity of the process fluid. A recovery process loop 110 may include either or both of a chemical substitution process, and an electrolytic process, effective to separate the Alkali metal or Alkaline earth metal from the undesired element or another compound.

Provided herein in is a method of removing phosphorus from a liquid hydrocarbon that includes the steps of (a) contacting the liquid hydrocarbon with an aqueous solution that comprises an oxidizing agent to form a reaction mixture that comprises an aqueous component and a hydrocarbon component, wherein the liquid hydrocarbon comprises at least an alkene.sub.(C4-30), and a phosphine.sub.(C?30); (b) reacting the oxidizing agent with the phosphine.sub.(C?30) to form the corresponding phosphine oxide.sub.(C?30); and (c) separating the aqueous component from the hydrocarbon component, thereby removing the phosphine oxide.sub.(C?30) from the liquid hydrocarbon.

The present invention relates to a process for regenerating a used lubricant composition, especially used for regenerating an engine drain oil, comprising the steps of: fractionating said used lubricant composition in a countercurrent fractional distillation column with a countercurrent flow of supercritical carbon dioxide (sCO.sub.2), wherein said used lubricant composition and supercritical CO.sub.2 are fed in the countercurrent column with a ratio of the sCO.sub.2 flow rate on used lubricant flow rate ranging from 15 to 50; and recovering the regenerated oil extracted within the supercritical CO.sub.2.

It further relates to a process for preparing a lubricant composition from a regenerated base oil obtained according to the invention.

The present invention relates to a process for regenerating a used lubricant composition, especially used for regenerating an engine drain oil, comprising the steps of: fractionating said used lubricant composition in a countercurrent fractional distillation column with a countercurrent flow of supercritical carbon dioxide (sCO.sub.2), wherein said used lubricant composition and supercritical CO.sub.2 are fed in the countercurrent column with a ratio of the sCO.sub.2 flow rate on used lubricant flow rate ranging from 15 to 50; and recovering the regenerated oil extracted within the supercritical CO.sub.2.

It further relates to a process for preparing a lubricant composition from a regenerated base oil obtained according to the invention.

The present invention relates to a process of deodorization of a at least partly regenerated lubricating oil, said process comprising the steps of: fractionating the at least partly regenerated lubricating oil in a countercurrent fractional distillation column with a countercurrent flow of supercritical carbon dioxide (sCO.sub.2), wherein said oil and supercritical CO.sub.2 are fed in the countercurrent column with a ratio of the sCO.sub.2 flow rate on oil flow rate ranging from 15 to 50; and recovering the deodorized lubricating oil which is freed of the bad smelling fraction, said bad smelling fraction being extracted within the supercritical CO.sub.2.

It further relates to a process for preparing a lubricant composition from a deodorized base oil obtained according to the invention.

The present invention relates to a process of deodorization of a at least partly regenerated lubricating oil, said process comprising the steps of: fractionating the at least partly regenerated lubricating oil in a countercurrent fractional distillation column with a countercurrent flow of supercritical carbon dioxide (sCO.sub.2), wherein said oil and supercritical CO.sub.2 are fed in the countercurrent column with a ratio of the sCO.sub.2 flow rate on oil flow rate ranging from 15 to 50; and recovering the deodorized lubricating oil which is freed of the bad smelling fraction, said bad smelling fraction being extracted within the supercritical CO.sub.2.

It further relates to a process for preparing a lubricant composition from a deodorized base oil obtained according to the invention.

Process of extracting sulphur-containing compounds from a hydrocarbon cut of the gasoline or LPG type by liquid-liquid extraction with a soda solution employing a unit (2) for pretreatment of the feedstock to be treated located upstream of the unit (4) for extraction with soda, said pretreatment unit consisting of a first pretreatment reactor operating in batch mode followed by a second continuous reactor of the piston type operating in piston mode.

Process of extracting sulphur-containing compounds from a hydrocarbon cut of the gasoline or LPG type by liquid-liquid extraction with a soda solution employing a unit (2) for pretreatment of the feedstock to be treated located upstream of the unit (4) for extraction with soda, said pretreatment unit consisting of a first pretreatment reactor operating in batch mode followed by a second continuous reactor of the piston type operating in piston mode.

Methods are provided for extracting heterocyclic compounds, organometallic compounds, and polynuclear aromatic hydrocarbons from a hydrocarbon feedstock such as crude oil or a crude fraction. The heterocyclic compounds and organometallic compounds are removed from the hydrocarbon feedstock through one or more successive extractions to form a first raffinate. The extractions use a first solvent system containing an ionic liquid formed from carbon dioxide and water. The polynuclear aromatic hydrocarbons are removed from the first raffinate using a second solvent system containing an aprotic solvent such as NMP, DMSO, aromatics, or combinations thereof. The extracted compounds remain chemically intact and may be fractionated for further applications. Further methods are provided for producing a hydrocarbon raffinate having reduced levels of heterocyclic compounds, organometallic compounds, and 2-4 cycle polynuclear aromatic hydrocarbons.

Methods are provided for extracting heterocyclic compounds, organometallic compounds, and polynuclear aromatic hydrocarbons from a hydrocarbon feedstock such as crude oil or a crude fraction. The heterocyclic compounds and organometallic compounds are removed from the hydrocarbon feedstock through one or more successive extractions to form a first raffinate. The extractions use a first solvent system containing an ionic liquid formed from carbon dioxide and water. The polynuclear aromatic hydrocarbons are removed from the first raffinate using a second solvent system containing an aprotic solvent such as NMP, DMSO, aromatics, or combinations thereof. The extracted compounds remain chemically intact and may be fractionated for further applications. Further methods are provided for producing a hydrocarbon raffinate having reduced levels of heterocyclic compounds, organometallic compounds, and 2-4 cycle polynuclear aromatic hydrocarbons.