Attainable region of reactive distillation—Part IV: Inclusion of multistage units for complex reaction schemes

Abstract

Reactive distillation (RD) can be advantageously used to improve selectivity of the desired product in a multi-reaction system. Because of the complexity in vapor liquid equilibrium and reaction kinetics, the design methodology is not straightforward and one has to adopt conceptual design and synthesis methods to arrive at the appropriate RD configuration. This paper is continuation of our earlier work (Amte et al., 2011), aimed at extending the concept of attainable region to a larger family of reactors that includes different reactive distillation units. In this work, we incorporate multistage reactive rectification and reactive stripping models with total reflux and total reboil, respectively. We further define the respective vectors, which justify the need of the corresponding units in the RD network. The van de Vusse schemes with both non-azeotropic and azeotropic vapor−liquid equilibria are considered and the attainable regions are constructed. Explanation is provided based on the visualization of selectivity lines in the composition space. In all the cases studied here, the feasible region is significantly broader than the one realized for the network of only conventional reactors.