Abstract: A process for treating a feed comprising C.sub.5.sup.+ hydrocarbons and comprising at least one unsaturated C.sub.6.sup.+ compound including benzene, is such that the feed is treated in a distillation zone, associated with a hydrogenation zone, comprising at least one catalytic bed, in which the hydrogenation is carried out of unsaturated C.sub.6.sup.+ compounds contained in the feed, and whereof a charge for the hydrogenation step is removed at the height of a removal level and represents at least part of the liquid flowing in the distillation zone, and the effluent from the hydrogenation reaction zone is at least in part reintroduced into the distillation zone to ensure continuity of the distillation operation, the effluents at the top and bottom on the distillation zone being very depleted of unsaturated C.sub.6.sup.+ compounds. The effluent drawn off from the top of the distillation zone is treated in a zone for the isomerisation of C.sub.5 and/or C.sub.6 paraffins.

Abstract: In a process for the separation of p-xylene from a feed to be treated containing a mixture of xylenes and olefinic impurities, at least a portion of the feed is circulated in an enrichment zone (14) to enrich a first fraction (15) in p-xylene and provide a second fraction (18) which is depleted in p-xylene. The second fraction is circulated in an isomerisation zone (19) and an isomerate (20) is recovered which is recycled to the enrichment zone. At least a portion of the feed to be treated, the isomerate, or a mixture thereof is circulated in at least one selective hydrogenation zone (3) to partially remove the olefinic impurities and thereafter in at least one clay tretment zone (8) to remove additional olefinic impurities. An effluent is recovered which is sent to the enrichment zone.

Abstract: A process is described for the high-efficiency selective hydrogenation of an aromatic hydrocarbon cut which also contains monoolefinic hydrocarbons and polyolefinic and/or acetylenic hydrocarbons with a bromine number of 10000 to 100 mg per 100 g of product with an aromatic degree of conversion which is limited to a maximum of 0.15% by weight, the process being characterized in that the cut, which is at least partially in the liquid phase, is passed with hydrogen into a hydrogenation zone in contact with a catalyst containing 0.1% to 1% by weight (with respect to the support) of palladium, the catalyst having been treated before activation with at least one organic sulphur-containing compound to introduce 0.05% to 1% of sulphur (by weight with respect to the weight of the catalyst), the process being carried out at a temperature in the range 20.degree. C. to 25.degree. C., at a pressure of 4-50 bar, a GHSV of 0.2-25 h.sup.-1 and with a H.sub.2 /monoolefin +polyolefin and/or acetylenes ratio in the range 0.

Abstract: The invention is concerned with a process for treating a charge of which the major part is constituted by hydrocarbons comprising at least 5 carbon atoms per molecule and comprising at least one unsaturated compound comprising at the most six carbon atoms per molecule including benzene, such that said charge is treated in a distillation zone, comprising a drainage zone and a stripping zone, associated with a hydrogenation reaction zone, comprising at least one catalytic bed, in which hydrogenation is carried out of at least part of the unsaturated compounds comprising at the most six carbon atoms per molecule and contained in the charge, the charge of said reaction zone being removed at the height of a removal level and representing at least a part of the liquid flowing in the distillation zone, the effluent of the reaction zone being at least partly reintroduced into the distillation zone, in such a way as to ensure the continuity of the distillation operation and in such a way as to remove from the top of t