METHOD FOR SWEETENING AN OLEFINIC PETROL OF SULPHIDE-TYPE COMPOUNDS

摘要

The present invention relates to a method for reducing the content of sulphide-type compounds of formula R1‑S‑R2, with R1 and R2 selected from methyl (CH3) and ethyl (C2H5) radicals, of a petrol containing diolefins, monoolefins and sulphur, in which: A) brought into contact in a reactor are the petrol as a mixture with a portion of the light petrol cut recycled from step C) and hydrogen and with a catalyst A comprising at least one metal from group VIb and at least one non-noble metal from group VIII which are deposited on a support, so as to produce an effluent having a content of diolefins and a content of sulphide-type compounds of formula R1‑S‑R2, with R1 and R2 selected from methyl (CH3) and ethyl (C2H5) radicals that are lower than that of the initial petrol; B) the effluent resulting from step A) is sent to a fractionating column in order to separate at the top a light petrol cut containing hydrocarbons having less than 6 carbon atoms per molecule and at the bottom of the column a heavy petrol cut containing hydrocarbons having 6 and more than 6 carbon atoms per molecule; C) a portion of the light petrol cut resulting from step B) is recycled in the reactor of step A) with a recycle ratio of between 0.1 and 0.7.