Our former method for the assessment of the feasibility of extractive distillation in a batch rectifier was extended for the investigation of the separation of maximum azeotropes. The method is based on the calculation of, the still path and possible composition profiles of the column sections. The sequence of the separation steps was determined, then limiting values and the influence of the most important parameters were investigated. The feasibility calculations performed to the mixture acetone-chloroform using benzene and toluene as solvent verified the benefits of the continuous feeding of the separating agent. (C) 2000 Elsevier Science Ltd. All rights reserved.