A systematic feasibility evaluation method is presented for batch reactive distillation columns with extractive feed streams. In this batch configuration, one feasibility, criterion is obtained for quaternary reactive systems by using residue curve maps and reaction equilibrium manifolds. If all reaction products are saddles and one of the binary azeotropes between the desired products and the other components is an unstable node, then a reactive rectifier with a side-feed entrainer can produce pure products regardless of the type and number of azeotropes involved in the system. (C) 2004 American Institute of Chemical Engineers.