The present invention relates to the field of the extraction of sulphur-containing compounds such as the mercaptans, COS or H.sub.2S from a hydrocarbon-containing cut. This selective extraction is carried out by bringing the hydrocarbon-containing cut in liquid phase into contact with an alkaline solution, for example soda. The process according to the invention is an improved process for the regeneration of the alkaline solution, making it possible to reduce the quantity of alkaline solution required in the regeneration section

The present invention relates to the field of extraction of sulphur-containing compounds such as mercaptans, COS, H.sub.2S or CS.sub.2 from a hydrocarbon cut. This selective extraction is carried out by bringing the hydrocarbon cut in the liquid phase into contact with an alkaline solution, for example caustic soda. The process in accordance with the invention is an improved process for the regeneration of alkaline solution which can be used to reduce the quantity of alkaline solution necessary in the regeneration section.

Methods and systems for applying separation processes to a spent caustic stream are disclosed. Methods and systems for regenerating media utilized in spent caustic separation processes are disclosed.

Methods and systems for applying separation processes to a spent caustic stream are disclosed. Methods and systems for regenerating media utilized in spent caustic separation processes are disclosed.

One exemplary embodiment can be a process for oxidizing one or more thiol compounds from an alkaline stream. The process may include passing a mixed stream having the alkaline stream to a vessel having an oxidation section, a separation section and a vent gas section. Often, the oxidation section includes a body containing one or more packing elements. The process can further include passing an oxidized alkaline stream to the separation section containing a first chamber and a second chamber. Usually, the first chamber contains a coated mesh and packing. The two sections further form a neck contains a packing, a distributor, and a mesh.

One exemplary embodiment can be a process for oxidizing one or more thiol compounds from an alkaline stream. The process may include passing a mixed stream having the alkaline stream to a vessel having an oxidation section, a separation section and a vent gas section. Often, the oxidation section includes a body containing one or more packing elements. The process can further include passing an oxidized alkaline stream to the separation section containing a first chamber and a second chamber. Usually, the first chamber contains a coated mesh and packing. The two sections further form a neck contains a packing, a distributor, and a mesh.

One exemplary embodiment can be a process for oxidizing one or more thiol compounds from an alkaline stream. The process may include passing a mixed stream having the alkaline stream to a vessel having an oxidation section, a separation section and a vent gas section. Often, the oxidation section includes a body containing one or more packing elements. The process can further include passing an oxidized alkaline stream to the separation section containing a first chamber and a second chamber. Usually, the first chamber contains a coated mesh and packing. The two sections further form a neck contains a packing, a distributor, and a mesh.

Provided are a layer-separation method of a spent caustic solution, and a recycling method of an additive, and more particularly, a layer-separation method of a spent caustic solution including: injecting an additive and an acidic compound to the spent caustic solution occurring from a refinery process to break down a red oil emulsion and to perform layer-separation into an upper layer fraction and a lower layer fraction, wherein the additive is an aliphatic hydrocarbon compound having a water solubility of 0.1 to 10 g/L at 20 C.

Provided are a layer-separation method of a spent caustic solution, and a recycling method of an additive, and more particularly, a layer-separation method of a spent caustic solution including: injecting an additive and an acidic compound to the spent caustic solution occurring from a refinery process to break down a red oil emulsion and to perform layer-separation into an upper layer fraction and a lower layer fraction, wherein the additive is an aliphatic hydrocarbon compound having a water solubility of 0.1 to 10 g/L at 20 C.

The present invention relates to a bio-assisted method for treatment of spent caustic by treating with haloalkaliphilic consortium of bacteria capable of reducing or transforming sulphides, thiols, mercaptants and other sulphur containing compounds, phenols, hydrocarbons, naphthenic acids and their derivatives in spent caustic.