To obtain the optimum distribution of liquid holdup or catalyst volume in the reactive zone for the design of a reactive distillation (RD) column considering selectivity targets

a design and optimization framework based on the combination of exergy loss analysis and process simulation were proposed. An exergy calculation model was established

including both physical and chemical exergy values

according to which the causes of exergy loss could be revealed with insights that provided the evolutionary direction of optimization. By linking the reaction volume distribution with exergy loss

the design of a reactive distillation column with the minimum reboiler heat duty could be accomplished by using the proposed optimization methodology. The proposed methodology was validated by the application to a reactive distillation column for producing ethylene glycol (EG) by hydration of ethylene oxide (EO). The optimized reaction volume distribution could reduce total energy consumption by 18%

compared with the commonly used even reaction volume design. In addition

the effect of energy saving obtained in this work was better than that reported in literature.