Procedure for obtaining 1,3-butadiene by extractive distillation from a fraction with 4 carbon atoms.

Process for preparing 1, 3-butadiene blank by extractive distillation from a fraction with four carbon atoms with a selective solvent, wherein the process is carried out in a dividing wall column (TK), in which is arranged a dividing wall (T) in the longitudinal direction of the column to form a first subregion (a), a second subregion (B) and a common area (C) of the column, bottom and upstream of which is connected a wash column extraction (K).