Process for lowering the content of benzene and of light unsaturated compounds in hydrocarbon fractions

摘要

Treating a hydrocarbon cut comprising 5C minimum hydrocarbons and containing at least one unsaturated 6C hydrocarbon including benzene comprises distillation in a unit comprising a draining zone and rectification zone associated with a reactive hydrogenation zone containing a catalyst bed in which hydrogenation of benzene and light olefins is effected. The charge for the reactive zone is taken at a sampling level from the distillation zone and the effluent from the reactive zone is returned to the distillation zone to ensure continuity. Finally, a head and base effluent very depleted in unsaturated compounds up to 6C is obtained. The zone of hydrogenation is partly external to the distillation zone.