The dynamic characteristics of an extractive distillation column for dehydration of aqueous ethanol mixture are investigated. The objective is to analyse the sensibility and stability of the process to perturbations in its main variables to be possible to recommend the best variables to be manipulated. Taking this into account, it was developed a model which considers the main phenomena taking place, i. e. it incorporates the effects of simultaneous mass and heat transfers as well as hydraulic behavior of the plates. Furthermore, it contains a rigorous consideration of the phase equilibria representation, once, in this case, the system is highly non-ideal. The mathematical modeling results in a system of differential equations which is solved by Gear's procedure. The dynamic behavior was analysed from the knowledgment of the effect of composition variation of the feed stream, rate of solvent and reflux flow rate. The quality of the final product can be achieved manipulating the solvent flow rate once the temperature of the upper part of the column, p.e., plate 18 and 22, is very sensitive to the performed modifications. © 1995.19SUPPL. 1405408Black, Distillation Modeling of Ethanol Recovery and Dehydration Processes for Ethanol and Gasohol (1980) Chem. Eng. Progr., 76 (9), p. 78Gallun, Holland, Gear's Procedure for The Simultaneous Solution of Differential and Algebraic Equation With Aplication to Unsteady State Distillation Problems (1982) Computers Chem. Engng, 30, p. 3Gani, Ruiz, Cameron, A Generalized Model for Distillation Columns-I (1986) Computers & Chemical Engineering, 10, p. 3Gear, (1971) Numerical Initial Value Problems in Ordinary Differential Equations, , Prentice Hall, Englewwod Cliffs, NJLee, Pahl, Solvent Screening Study and Conceptual Extractive Distillation Process to Produce Anhydrous Ethanol From Fermentation Broth (1985) Ind. Eng. Chem. Proc. Des. Dev., 24, p. 168Lynn, Hanson, Multieffect Extractive Distillation For Separating Aqueous Azeotropes (1986) Eng. Eng. Chem. Proc. Des. Dev., 25, p. 936Maciel, (1989) PhD thesis, , Leeds University, England, U. KMagnussen, Michelsen, Fredenslund, Azeotropic Distillation Using UNIFAC (1979) Inst. Chem. E. symp. Ser., 56, p. 4.2. , Int. Symp. on Distillation, ICE Rugby, Warwickshire, EnglandMartini, (1995) M. Sc. Thesis, , UNICAMP, SP, BrasilMeirelles, Weiss, Herfurth, Ethanol Deydration By Extractive Distillation (1992) J. Chem. Tech. Biotechnol., 53, p. 268Prokopakis, Seider, Feasible Specifications in Azeotropic Distillation (1983) AIChE J., 29, p. 49Rovaglio, Doherty, Dynamics of Heterogeneous Azeotropic Distillation Columns (1990) AIChE Journal, 36, p. 1