Disclosed are a pretreatment method and system for a fraction oil for the production of alkylbenzene, the method comprising: adding a fraction oil, a weak base solution and an inorganic salt solution into a reactor, and leaving same to stand and layering same after the reaction is complete; adding water and an inorganic salt solution into an oil phase for washing with water; extracting same with a polar solvent having a high boiling point, and then adsorbing same with an adsorbent to separate oxygen-containing compounds in the neutral fraction oil; sending the extraction agent containing the oxygen-containing compounds to an extraction agent recovery unit; and then sending the neutral fraction oil to an alkylation reactor for a reaction.

A method for removing sulfur containing contaminants from a thermally cracked waste oil is disclosed. In the present invention, the substantial amount of contaminants containing sulfur is separated into a solvent and further remaining contaminants can be separated via adsorption with bauxite such that an end product oil having better quality may be produced with higher productivity. The solvent can be subject to flash evaporation and then be recycled.

A method for removing sulfur containing contaminants from a thermally cracked waste oil is disclosed. In the present invention, the substantial amount of contaminants containing sulfur is separated into a solvent and further remaining contaminants can be separated via adsorption with bauxite such that an end product oil having better quality may be produced with higher productivity. The solvent can be subject to flash evaporation and then be recycled.

Metals, such as mercury, may be removed from aqueous, hydrocarbon, or mixed oilfield or refinery fluids by: applying a sulfur compound having the general formula HS-X, wherein X is a heteroatom substituted alkyl, cycloalkyl, aryl, and/or alkylaryl group either alone or in combination with or as a blend with at least one demulsifier, a buffering agent, a pour point depressant, and/or a water clarifier to chelate the at least one metal and form a chelate complex of the sulfur compound with the at least one metal and then separating the chelate complex from the fluid.

Metals, such as mercury, may be removed from aqueous, hydrocarbon, or mixed oilfield or refinery fluids by: applying a sulfur compound having the general formula HS-X, wherein X is a heteroatom substituted alkyl, cycloalkyl, aryl, and/or alkylaryl group either alone or in combination with or as a blend with at least one demulsifier, a buffering agent, a pour point depressant, and/or a water clarifier to chelate the at least one metal and form a chelate complex of the sulfur compound with the at least one metal and then separating the chelate complex from the fluid.

A method for removing sulfur containing contaminants from a thermally cracked waste oil is disclosed. In the present invention, the substantial amount of contaminants containing sulfur is separated into a solvent and further remaining contaminants can be separated via adsorption with bauxite such that an end product oil having better quality may be produced with higher productivity. The solvent can be subject to flash evaporation and then be recycled.

A method for removing sulfur containing contaminants from a thermally cracked waste oil is disclosed. In the present invention, the substantial amount of contaminants containing sulfur is separated into a solvent and further remaining contaminants can be separated via adsorption with bauxite such that an end product oil having better quality may be produced with higher productivity. The solvent can be subject to flash evaporation and then be recycled.

Treatment of hydrocarbon streams, and in one non-limiting embodiment refinery distillates, with reducing agents, such as borohydride and salts thereof, alone or together with at least one co-solvent results in reduction of the sulfur compounds such as disulfides, mercaptans, thiophenes, and thioethers that are present to give easily removed sulfides. In one non-limiting embodiment, the treatment converts the original sulfur compounds into hydrogen sulfide or low molecular weight mercaptans that can be extracted from the distillate with caustic solutions, hydrogen sulfide or mercaptan scavengers, solid absorbents such as clay or activated carbon or liquid absorbents such as amine-aldehyde condensates and/or aqueous aldehydes.

Treatment of hydrocarbon streams, and in one non-limiting embodiment refinery distillates, with reducing agents, such as borohydride and salts thereof, alone or together with at least one co-solvent results in reduction of the sulfur compounds such as disulfides, mercaptans, thiophenes, and thioethers that are present to give easily removed sulfides. In one non-limiting embodiment, the treatment converts the original sulfur compounds into hydrogen sulfide or low molecular weight mercaptans that can be extracted from the distillate with caustic solutions, hydrogen sulfide or mercaptan scavengers, solid absorbents such as clay or activated carbon or liquid absorbents such as amine-aldehyde condensates and/or aqueous aldehydes.

Methods are provided for processing deasphalted gas oils derived from thermally cracked resid fractions to form Group I, Group II, and/or Group III lubricant base oils. The yield of lubricant base oils (optionally also referred to as base stocks) can be increased by thermally cracking a resid fraction at an intermediate level of single pass severity relative to conventional methods. By performing thermal cracking to a partial level of conversion, compounds within a resid fraction that are beneficial for increasing both the viscosity and the viscosity index of a lubricant base oil can be retained, thus allowing for an improved yield of higher viscosity lubricant base oils from a thermally cracked resid fraction.