METHOD OF CONTINUOUSLY SEPARATING C-FRACTION Russian patent published in 2008 - IPC C07C7/08 C07C11/167 

FIELD: petrochemical processes.

SUBSTANCE: invention relates to a method for continuously separating C₄-fraction by extractive distillation using selective solvent on extractive distillation column, which method is characterized by a separation barrier disposed in extractive distillation column in longitudinal direction extending to the very top of the column to form first zone, second zone, and underlying common zone. Butanes (C₄H₁₀)-containing top stream is withdrawn from the first zone, butenes (C₄H₈)-containing top stream is withdrawn from the second zone, and C₄H₆ stream containing C₄-fraction hydrocarbons, which are more soluble in selective solvent than butanes and butenes, is withdrawn from underlying common zone of column.

EFFECT: reduced power consumption and expenses.

15 cl, 2 dwg, 2 ex