Optimization based conceptual design of reactive distillation for selectivity engineering

Reactive distillation can be effectively used to enhance the selectivity of the desired product in a multi-reaction system. Due to complex interaction of reactions and distillation, identification of an appropriate reactive distillation configuration for the known performance targets has been a challenge. The objective of this contribution is to present an MINLP optimization technique that would assist one to identify a suitable configuration for selectivity maximization at conceptual design level. An illustrative example of industrially important reaction of dimerization of isobutene for maximizing the selectivity toward di-isobutene is considered. The results of the optimization are found to be in agreement with those obtained by performing independent simulation using ASPEN PLUS simulator. Thus, the work highlights the potential of an optimization based tool for conceptual design of reactive distillation that involves complex reaction systems.

► The potential of reactive distillation for the reacting systems containing inert components is evaluated using MINLP optimization technique.
► For more volatile reactant, the continuous reactive rectification and continuous reactive rectification with distillate withdrawal configurations can be used depending on the volatility of inert.
► Depending on the volatility of components involved in reaction, suitable RD configurations can be suggested.
► The optimization technique is applied to dimerization of IB in the presence of an inert to arrive at an optimal RD configuration.