A process reducing sulfides R1-S-R2, with R1 and R2 methyl or ethyl, in a gasoline containing diolefins, mono-olefins and sulphur: A) contacting gasoline in mixture with a light gasoline cut recycled from C) and hydrogen in a reactor with catalyst A at least one VIb metal and at least one non noble group VIII metal on a support, producing effluent having diolefins and sulfides R1-S-R2, with R1 and R2 methyl or ethyl radicals lower than that that of the starting gasoline; B) the effluent from A) is sent into a fractionating column separating at the top a light gasoline cut containing hydrocarbons having less than 6 carbon atoms per molecule and at the bottom a heavy gasoline cut containing hydrocarbons having 6 and more than 6 carbon atoms per molecule; C) recycling a part of the light gasoline from B) to the reactor of A) with a recycle ratio 0.1 to 0.7.

The present invention relates to a method for treating a pyrolysis gasoline C5.sup.+ containing monoolefinic, diolefinic and sulfur hydrocarbons, comprising at least, and in any order: a) a step of hydrotreating the pyrolysis gasoline or a hydrocarbon fraction C6.sup.+ originating from the pyrolysis gasoline, in the presence of hydrogen and at least one hydrotreatment catalyst at a temperature ranging between 220 and 380 C. so as to produce a hydrotreated effluent; b) a step of separating the pyrolysis gasoline or the hydrotreated effluent originating from step a) when said step is completed before step b), into a separation column for separating into a top hydrocarbon fraction C5.sup. and a bottom hydrocarbon fraction C6.sup.+, said separation column comprising a reboiling section including two heat exchangers, at least one of the two exchangers being configured to perform a heat exchange with a portion of the bottom fraction that is recycled in the column via the reboiling section. According to the invention, one of the two heat exchangers of the reboiling section is supplied with at least one portion of the hydrotreated effluent so as to supply part of the heat required to operate the reboiling section.

The present invention relates to a method for treating a pyrolysis gasoline C5.sup.+ containing monoolefinic, diolefinic and sulfur hydrocarbons, comprising at least, and in any order: a) a step of hydrotreating the pyrolysis gasoline or a hydrocarbon fraction C6.sup.+ originating from the pyrolysis gasoline, in the presence of hydrogen and at least one hydrotreatment catalyst at a temperature ranging between 220 and 380 C. so as to produce a hydrotreated effluent; b) a step of separating the pyrolysis gasoline or the hydrotreated effluent originating from step a) when said step is completed before step b), into a separation column for separating into a top hydrocarbon fraction C5.sup. and a bottom hydrocarbon fraction C6.sup.+, said separation column comprising a reboiling section including two heat exchangers, at least one of the two exchangers being configured to perform a heat exchange with a portion of the bottom fraction that is recycled in the column via the reboiling section. According to the invention, one of the two heat exchangers of the reboiling section is supplied with at least one portion of the hydrotreated effluent so as to supply part of the heat required to operate the reboiling section.

The present disclosure relates to hydrogenation reactions of different fractions in oil refining. It also relates to a process device applicable thereto for hydrogenation of various feedstocks, such as arrangements during campaign changes.

The present disclosure relates to hydrogenation reactions of different fractions in oil refining. It also relates to a process device applicable thereto for hydrogenation of various feedstocks, such as arrangements during campaign changes.

The present invention provides a two-stage process for removing polyunsaturated hydrocarbons from C4 hydrocarbon streams that, in addition to C4 hydrocarbons, also contain C5 hydrocarbons and mercaptans and/or disulfides.

A process for the desulphurization of a gasoline cut containing sulphur-containing compounds, olefins and diolefins, involving (a) fractionating the gasoline in order to recover a light gasoline cut LCN and a first heavy gasoline cut HCN; (b) desulphurization of the first heavy gasoline cut HCN; (c) partially condensing desulphurization effluent obtained from b) in a manner such as to produce a gaseous phase of hydrogen and H.sub.2S and a liquid hydrocarbon phase HCN of dissolved H.sub.2S; (d) separating the liquid hydrocarbon phase HCN into an intermediate gasoline cut MCN and a second heavy gasoline cut HHCN; (e) carrying out a second desulphurization of the second heavy gasoline cut HHCN.

A process for the desulphurization of a gasoline cut containing sulphur-containing compounds, olefins and diolefins, involving (a) fractionating the gasoline in order to recover a light gasoline cut LCN and a first heavy gasoline cut HCN; (b) desulphurization of the first heavy gasoline cut HCN; (c) partially condensing desulphurization effluent obtained from b) in a manner such as to produce a gaseous phase of hydrogen and H.sub.2S and a liquid hydrocarbon phase HCN of dissolved H.sub.2S; (d) separating the liquid hydrocarbon phase HCN into an intermediate gasoline cut MCN and a second heavy gasoline cut HHCN; (e) carrying out a second desulphurization of the second heavy gasoline cut HHCN.

The invention provides processes for the production of hydrocarbons from a biorenewable feedstock blended with a mineral feedstock comprises hydrotreating to remove heteroatoms and saturate olefins. The carbon monoxide is not fed to the downstream hydroisomerization reactor but supplanted with a hydrogen gas with a low concentration of carbon monoxide so as not to poison the hydroisomerization catalyst to improve the cold flow properties for a diesel fuel.

The invention provides processes for the production of hydrocarbons from a biorenewable feedstock blended with a mineral feedstock comprises hydrotreating to remove heteroatoms and saturate olefins. The carbon monoxide is not fed to the downstream hydroisomerization reactor but supplanted with a hydrogen gas with a low concentration of carbon monoxide so as not to poison the hydroisomerization catalyst to improve the cold flow properties for a diesel fuel.