METHOD OF PRODUCING PURE HYDROCARBONS FROM MIXTURE CONTAINING AROMATIC AND NONAROMATIC HYDROCARBONS Russian patent published in 1999 - IPC

FIELD: petrochemical processes. SUBSTANCE: invention, in particular, relates to mixture enriched with aromatic hydrocarbons that is subjected to extractive distillation. First stream of a part of selective solvent (N-substituted morpholine) is fed into middle part of extractive distillation column. From top part of column, chiefly nonaromatic refinement product is withdrawn whereas mainly aromatic hydrocarbons in selective solvent are discharged from the bottom part of column. Second stream of selective solvent (less than 50% of total amount of solvent) is fed into upper part of column at the level higher than first-stream inlet. EFFECT: enhanced process efficiency. 7 cl, 2 dwg