The extractive and autoextractive distillation of ternary and quaternary azeotropic solvent mixtures was adopted to demonstrate the relation between the structure of phase diagram of the azeotropic systems and the operating parameters of the extractive distillation column based on the relative volatility criterion. A set of separation schemes belonging to different structural classes have been investigated. The separation scheme that has the lower energy consumption is revealed for separation of four-component solvent mixturesacetone-n-butanol-chloroform (or toluene) and dimethylformamidethat were used in the production of thermal stabilizer stabilin-9.