Process and device for separating aromatics under vacuum

Device for separating a feedstock comprising benzene and/or toluene and compounds comprising 8 carbon atoms or more, comprising at least one “reformate” distillation column (C1), one aromatics extraction unit (P1), one para-xylene separation unit (P2), one xylene isomerization unit (P3) and one transalkylation unit (P4), the separation device also comprising the following columns for the distillation of the effluents of the units:

• purification column (C6), deheptanizer (C7) and toluene column (C10),
• in which at least one of the distillation columns (C1, C6, C7 and C10) is suitable for being operated under vacuum so that:
• the majority of the compounds comprising 7 carbon atoms or less are recovered in the top of the distillation column operated under vacuum, and
• the majority of the compounds comprising 8 carbon atoms or more are recovered in the product at the bottom of the distillation column operated under vacuum.