A conceptual design methodology for the synthesis of reactive distillation columns is presented. The method assesses feasibility of a proposed reactive distillation column, designs the column and allows evaluation of the design for both fully reactive and 'hybrid' column configurations. Stage composition lines are used to represent all possible liquid compositions in a column section, for specified product compositions and for all reflux or reboil ratios. Reaction equilibrium is assumed on each reactive stage, and vapour-liquid equilibrium is assumed on all stages. The graphical column design method allows fast and relatively simple screening of different reactive distillation column configurations. The methodology is illustrated by application to an ideal reactive system and for MTBE production. (C) 2003 Elsevier B.V. All rights reserved.